Introduction to Ontological Philosophy: Inside-Out Encyclopedia

The Wholeness of the World was given to me by a stranger I met recently at a Midwestern airport when I was delayed between flights. I am not quite sure what to make of it. Having taught philosophy for over a quarter century, I thought what he told me at the time made surprisingly good sense. And after reading what he gave me, I wonder why I shouldn't accept it. But it is not up to me. Others need to consider it. The best way to share it seems to be the Internet. He called it an "inside-out encyclopedia," but in order to explain what he meant by that -- and to introduce tWoW.net -- let me tell you the story about our encounter.

I was in line at one of those indistinguishable airport food dispensaries deciding whether to have a bagel and cream cheese with my coffee. A delayed flight had left me with a couple of hours to kill, but for some reason, I was feeling rather cheerful . Having accidentally bumped into a young man getting into line, I said I was sorry, and to coat my apology with a little humor, I quipped, when the bagel was delivered, "That's not a real bagel. That's a Wonder Bread imitation of a bagel."

"That's just your interpretation of it," the young stranger replied brightly. "They surely see it as a real bagel."

His comment had the ring of relativism. Perhaps he was a multi-culturalist or a victim of deconstructionism, the now fashionable relativism in literature studies. As an old fashioned philosophy teacher, I tried to draw him out. "But isn't that just your interpretation of what I am saying? Aren't you just commenting on my comment?"

"Well, yes, I suppose so," he said in a more somber tone, "but that doesn't mean there isn't a truth of the matter about the bagel. I'm no relativist. In fact, I believe there is an absolute truth."

That intrigued me. Relativism is so much the currency of popular culture these days that I meet few students who don't take it for granted. And the stranger could not have been more than a few years out of college. "Really? That's uncommon these days," I replied, "But I have to admit that I agree with you."

"Oh, you do? You believe there is an absolute truth?" Looking a bit skeptical, the young stranger said, "I'd be interested to know what you mean." He glanced back at the seating area and, hesitating briefly, said, "Perhaps you would like to share a table? My flight doesn't leave for a while."

Young people don't usually take much interest in people like me. But this young man seemed eager to talk. He was rather attractive on the whole, neat and clean, though in a casual way. And I thought it might be fun to pass the time arguing with him about relativism.

When we arrived at the table, he held out his hand and said, "I'm Hugh."

"Nice to meet you. My name is Phillip."

As we sat down, he got right to the point, "And so why do you say that you agree with me about there being an absolute truth?"

It was a point I often made in my classes, and I launched right in. "Relativism is the view that what is true depends on what you believe. Or, perhaps, what your group believes. In any case, it makes truth relative to the believer: what you believe is true for you and what I believe is true for me. But I can't help believing that the world is real. I mean this world, the world where we are talking to one another, really exists, including you and me. And if there is a real world, it has to exist in some way or another. It is something determinate. So whatever we may believe about the world, it is either true or false, because it either corresponds to what exists or not. And aside from confusion about the meanings of the terms we are using, it either corresponds or not the same way for everyone. That is what 'absolute' means: 'the same for everyone.' It means that, if there were a God, he would know something determinate, even if we cannot. That is why I agree with you about truth being absolute."

I think this way of defending absolute truth takes the wind out of the sails of relativism. I had had fun using it in my classes for years, though students are naturally reluctant to be convinced that something so universally accepted could be refuted so easily. Though Hugh was nodding in agreement, he added quickly, "But that is merely to refute relativism. You can deny relativism in that way without claiming to know anything about the world. All you know is that between any pair of contradictory statements, one is true and the other false. But you needn't know which. Either the universe will expand forever or it won't. No one knows. So you can still be a skeptic about knowing the truth. But when I say that there is an absolute truth, I mean that I know what it is."

Hugh's response took me aback. He understood what I was saying, and consequently how little it amounted to -- or how little it would amount to, if it weren't for the facile deconstructionist fashion in academia these days. Being caught off guard, I was a bit defensive. "Well, I'm not a skeptic either. I believe there are some things we know. Science, for example -- or at least, natural science. It has been too successful for too long not to be on to something real. Just look at the power it gives us over nature. Those airplanes out there, for example. And it's not easy to deny science, since it bases everything on what we observe." My habits from teaching philosophy of science were showing, and I wanted to speak more broadly. "And surely what perception tells us about the natural world is basically true, even if we can't prove it to the satisfaction of anyone who clings tenaciously to skepticism. The scientific method is simply the most adequate way of knowing we have. No other claim to systematic knowledge has the same capacity to win over people from every culture in the world."

"Fine," Hugh said, "but that's not absolute truth. That's just belief in a truth that, at best, happens to be true. It is true, and everyone may agree that it is. In that sense it may be absolute. But what I mean when I say that there is an absolute truth is that some doctrine is known to be absolutely true.

“The position you're defending is just 'scientism.' You are simply taking sides with the empirical method of science and the conclusions based on it, but without any deeper reason for doing so. You can't take the success of science as confirming it, unless you already accept 'prediction and control' as the criterion of truth. That is the criterion that scientists accept. But others accept other criteria of truth. There are theists, for example, who claim to know God by a mystical intuition of some kind. They simply accept the validity of mystical intuition without any deeper reason, as you do the scientific method. Poets have felt the same way about the sense of beauty. And most people feel that way about their native culture. You may not be a skeptic, but the position you take offers no reason for not being a skeptic. You still grant everything relativists really want to insist on. What they really believe is that there is, in principle, no way to tell which world view is true. You choose science. Others choose Eastern religion. And so on. But everyone has to choose."

At that point, I began to realize that I had been underestimating this young man. I agreed with him, of course. Even philosophers of science now admit that their naturalism is basically dogmatic, though they usually put it more delicately -- saying that they see philosophy as "continuous with" science, rather than as its foundation. But having pretty much shot the last round I had in my anti-relativism arsenal, I decided to turn the table. "So you say you know the absolute truth." It had crossed my mind that Hugh might be a fanatic of some kind, a true believer who made up in depth of feeling for what he lacked in reason. "Are you saying that you believe in an absolute truth with a capital 'A' and capital 'T'?"

"You could put it that way, if you want. Some would dismiss it as 'The One True Theory,' also capitalized, or as a 'God's Eye View' of the world. The important thing, in my view, is that what is known is the complete truth about the world. I take the Absolute Truth to be a belief about the basic nature of what exists in the world, that is, about the basic entities that make up the world. It's one that can account for everything in the world, including all the concrete objects, their properties, relations, how they change -- everything. And it can explain everything about the nature of the world."

I couldn't keep myself from trying to smoke him out. I asked him, "Do you believe in God?"

"Well, yes, in a way. God has a place in the Absolute Truth, though it's not quite what people believe." Hugh hesitated and then added, "But it is not just that I have faith in God, if that’s what you're getting at. When I say that the Absolute Truth is known, I mean that it is known by beings like us, using their rational faculties. Nothing about it is mystical or even mysterious. I'm merely saying that we can know the nature of the basic substances that constitute the world. And we can see how those substances explain the existence of everything in and about the world. That gives us the Absolute Truth."

The young man seemed too calm to be a fanatic. He was being reasonable. But he could be making the mistake of thinking he knew the Absolute Truth when he didn't. Indeed, he must be, given what I believed after teaching the history of philosophy for thirty years. Having all but accused him of being a true believer, however, I wanted to let him know that I thought there was a way I could agree with him about the basic nature of the world. What he seemed to be describing was materialism, a view that had always seemed plausible to me, given my sympathy for science.

"If that is what you mean by Absolute Truth," I began, "wouldn't materialism be the Absolute Truth? It holds that what makes up the world are material substances, or bits of matter that move and interact. Of course, physics tells us that the simplest particles are rather different from the atoms that Democritus described long ago -- and also different from Hobbes' view of matter at the beginning of modern science. There are just particles and fields. But still they are material substances of a kind. In any case, the laws of physics are a theory about the basic nature of what exists. They describe the basic entities that constitute everything in the world. And since everything happens in accordance with physical laws, this view is sometimes called "physicalism." But whatever it is called, materialism can account for everything in the world. It is the complete truth, if it is true at all. So it could be the Absolute Truth. Isn't that what you mean by Absolute Truth?"

"Well, something like that," he replied.

Hugh might have gone on, but I felt relieved, having pinned him down, and my reflex as a philosopher was to move in for the kill. "But the problem with materialism is that it's not true. Or at least, there are plenty of reasons for doubting that any such ontology can explain everything. Even biological functions are now recognized to be irreducible to physics, at least, in the strict sense. And if that seems like a mere technicality, there is still the problem about the nature of conscious mind. Even if science could explain how the brain works, that would not explain why it is 'like something' to perceive the world or have other conscious states. There is a subjective aspect to experience, the way it feels, and since that eludes materialism, there is some ground, at least, for believing that mind is not material at all. And that's not all. It seems to me and many others that there is a real difference between good and bad, and between right and wrong. It is something about the things themselves, not something about how I feel about them -- or how anyone else feels, for that matter. But that's the only way for materialists to explain what goodness is. In a world of just matter in motion, what difference does it make whether one thing rather than another happens? It has to come down to how beings like us feel about it." I felt I was beginning to regain a teacher's proper control over his student. "What is more, I have colleagues I respect very much who believe in God. They admit they can't prove the existence of God. But they insist that religious experience itself is something that materialism doesn't even come close to explaining. I'm not saying that I agree with them, but how could religion be so central to the lives of so many people, if there isn't really anything worthy of worship? In any case, even if we discount belief in God, materialism can't be true, if either consciousness or goodness is a real aspect of this world."

To my consternation, Hugh seemed to have a smile on his face. He was apparently amused by what I had said, and looking something like a cat playing with a mouse, he asked, "But what if those phenomena could be explained? Wouldn't materialism be the Absolute Truth then?"

"That is quite a bit to grant, isn't it?" I was ready to show him how intractable these problems really are.

"Yes, but right now we are not interested in what is absolutely true, but in what Absolute Truth is, and I want to know what would be wrong with calling materialism the Absolute Truth, if it did somehow explain all those phenomena."

"Well, if we are talking about Absolute Truth with a capital 'A' and capital 'T,' there is still a lot wrong. I think it would have to be something more special about knowing the Absolute Truth. It can't be just re-baptizing something we already believe about the basic nature of the world as “Absolute Truth” and then insisting on it with greater confidence. If materialism were the Absolute Truth, I’d expect it to tell us something more than what science tells us. Something more fundamental. At the minimum, knowing the Absolute Truth would mean knowing that some truths about the world hold necessarily. It can't be just a collection of facts that happen to be true."

"Well," Hugh protested, "if materialism were true, couldn't one insist that some truths about the world are necessary? It does imply, after all, that whatever science discovers to be causing any phenomenon, be it in the physics laboratory or the everyday world, it is ultimately nothing but the motion and interaction of bits of matter, or whatever you call the basic entities, in space over time. It is all just the playing out of the basic laws of physics."

"But even if that is necessarily true, it is just what science already assumes," I replied. "In fact, science is the reason for believing that materialism is true. Materialism might even be called the 'ontology of science.' It is what scientists believe about the substances making up the world. And if that is the Absolute Truth, it is an Absolute Truth that is strangely uninformative. It tells us nothing us about the world that science doesn't already believe. If materialism is the Absolute Truth, what is so significant about knowing it?"

I thought that this tirade against materialism as a metaphysics might stir up some opposition from the young stranger, but to my surprise, he was now clearly smiling. "Of course, you are right. It can't be the Absolute Truth, unless it reveals some new necessary truths about the world. But that is what I mean. The Absolute Truth I have in mind does tell us many new things about the natural world, things not already known by empirical science. They are prior to empirical science and other ordinary ways of knowing things because they are necessary. And when these necessary truths are combined with what is already known by science, they yield a complete explanation of the nature of the world. That is what I mean by the 'Absolute Truth.' And what is new are some truly important things, such as how consciousness is possible and what the difference between good and bad is. Wouldn't that count as an Absolute Truth in your book? Or do you still think I don't know the difference between truth being absolute and there being an absolute truth with a capital 'A'and capital 'T'?"

What Hugh was describing did seem like something that would have to be called "Absolute Truth," if it could be known to be true at all. New necessary truths that explained consciousness and goodness would certainly be special. So at that point, it seemed clear that I could no longer hope to agree with him by taking him to be giving some special, limited, acceptable meaning to the term, "absolute truth." He was clearly making the sort of claim that had been made repeatedly in the grand tradition of philosophy, from Plato and Aristotle to Descartes and Hegel. That left only one possibility, that there was something badly mistaken about his reasoning. And I was sure it was a mistake that some philosopher had already made. Traditional philosophers thought they had found a foundation from which to claim that certain propositions are necessarily true relative to what is discovered by empirical science. But we now know that philosophy was a failure. Rationalism does not work. There is no way to know that you have the Absolute Truth about the world by reflecting on how we know about it. Skepticism, if not relativism, is the lesson that everyone learns from the history of philosophy. Anyone who insists on having such an Absolute Truth in this century is rightly seen as lacking a higher education. Hugh was obviously smart enough to have got it, if he had gone to college.

"Have you been to college?" I asked tactlessly. "Surely you don't expect me to believe that you have found some way of defending Descartes or Plato?"

"More like Hegel, I would say." Hugh laughed, seeming almost gleeful about taking up my challenge. "I thought you might be someone who would understand what I am saying when we first met and you didn't just dismiss my comment about Absolute Truth out of hand. That is, besides the book I saw you carrying." But then he added quickly, "Of course, I'm not defending traditional philosophy. It is, rather, that there is another way of doing philosophy, one that does work and does entail truths that are necessary relative to empirical science. New truths."

Despite Hugh’s cheerful confidence, I was, of course, doubtful about this claim. After a lifetime of teaching, I had found no reason to believe that philosophy could ever attain its highest aspirations. I had even come to think of philosophy as basically mistaken, at least insofar as it claims to be anything more than just science or critical thinking. But I also like to think of myself as open minded – as someone who is willing to listen to an argument and to judge it on its merits. I am certainly not dogmatic. And since it was still more than an hour before my plane would be boarding, there was time to ask Hugh what he meant.

A restrained eagerness replaced the amusement on his face. "As you say, traditional philosophy had a foundation for defending necessary truths. But its foundation was some theory or other about how rational beings know about the world. Right?"

"Yes, that is what I meant by saying that it was based on reflection on how we know," I replied docilely. I sensed the table beginning to turn again.

"But that is epistemology, and the foundation of this new way of doing philosophy is ontology. An ontology is a theory about the nature of existence, and I take that to mean a theory about the kinds of basic substances that constitute the natural world. What such an ontology implies about specific issues are its necessary truths about the world. That's why I called them 'ontologically necessary truths.'"

I was puzzled. "But now we are back to materialism, aren't we?"

"Yes and no. Materialism is an ontology, but as you pointed out, it is based on science. It is the ontology that most scientists accept, when they take their theories about the world to be true and they reflect on their belief that the world being described is real and exists independently of them. They have to believe in matter, or particles and fields, if you prefer. You were right to deny that such an ontology could tell us anything that science does not already know. It is uninformative.

“But there is another way to approach ontology, the way the Pre-Socratic philosophers did way back before the beginning of traditional philosophy. From Thales through Democritus, they said that they were trying to discover the 'first principle,' or archê, for explaining everything in the world. It is clear in retrospect that what they were trying to discover was not the basic laws of nature, but rather the basic substances that make up the world. Thales thought it was water. Others thought it was air. Empedocles thought it was earth, air, fire and water. Of course, they didn't have the advantage of modern science. They didn’t know how the elementary bits of matter behave. The discovery of the laws of physics had to await the development of mathematics, among other things. But the Pre-Socratics could do without it. Their project was different from empirical science. They were looking for the best ontological explanation of the natural world."

"But," I protested, "they were mostly materialists, weren't they?" I had always thought of the Pre-Socratics as anticipating what we call "modern science."

"Right," Hugh agreed. "But they considered materialism as an ontological theory. They weren't merely describing the substances they were already committed to by the empirical laws they believed. They expected matter to explain the existence of the natural world and the basic features of what exists. In other words, they were looking for a different kind of explanation from science. Science tries to figure out the efficient causes of what happens in the world. That's why it looks for laws of nature and tests them by their capacity to predict and control what can be observed. But the Pre-Socratics were looking for the substances that explain everything in the world, including not only what happens in the world, but also what exists there. For example, they wanted to know not only how things change, but how there could be change at all. That made it possible for them to discover something that has been forgotten since then, something that makes it possible, in our era, to do philosophy in a new way."

There was an intensity and clarity about the way Hugh spoke at this point, as if it were the crux of everything. And my great admiration for the Pre-Socratics made me sympathetic, trapping me into his argument.

"What I am referring to is ancient atomism. As you probably know, Pre-Socratic philosophy developed in a dialectical way over several generations. New theories were tried out, criticized and revised again in light of criticisms. They were mostly materialists, but eventually their arguments led Leucippus and Democritus to insist that there are two elements, atoms and the void. The atomists recognized that the best ontological explanation of the natural world would have to recognize that space is just as much a substance constituting the world as matter is. The recognition that space and matter together constitute the world made it possible for them to explain aspects of the natural world that preceding materialists had simply taken for granted. Earlier Pre-Socratics had simply assumed that bits of matter have spatial relations, but the atomists could explain why objects have spatial relations. And though motion had to be possible in order to explain change by mixture and separation, the atomists could explain how motion is possible. And, thus, how change itself is possible. At least, that is how I understand the atomists. What they meant by the 'void' was something like a big three-dimensional container in which all the atoms had a location and could move. But modern science doesn't recognize that space is a substance in that sense. So my ontology differs from contemporary materialism in the same way that ancient atomism differed from the forms of materialism that preceded it. That's what makes it possible to defend new truths that are necessary relative to science. Space is a substance in their sense of a 'first principle,' an archê, along with matter, a giant three-dimensional container of all the matter in the world.”

I could see his point, though I wanted to hear more about how space is required to explain motion before I agreed that the ancient atomists had the best ontological explanation -- or for that matter, that this is what the ancient atomists believed. But I let that pass, because there was an even more obvious objection. Didn't Hugh know about Einstein? Once again, the young man was beginning to sound like someone lacking a twentieth century education. And once again my academic reflexes won out. "It is for good reason that science doesn't take space to be a substance. It does have an advantage over Democritus. It has learned about spacetime from Einstein. We now know that, if there is any 'substance,' as you call it, in addition to matter constituting the world, it's not space, but spacetime. To hold that space is a substance, enduring through time like matter, is to believe in absolute space and absolute time. That was Newton's view. But the Newtonian view is what was overthrown by contemporary physics." I refrained from adding, "Surely you have heard of Einstein."

"Yes, that is a problem all right," Hugh admitted, "but it's not my problem. It's a problem about contemporary science. Remember I'm defending an ontological position, not merely proposing a scientific theory. Physics accepted Einstein's special and general theories of relativity because they made new and unexpected predictions of precise measurements that turned out to be true. The empirical method used in science required them to accept relativity theory. But what goes unrecognized, even today, is that it is possible to formulate a theory with all the same empirical implications on the assumption that bits of matter are located in absolute space and absolute time. It all depends on how we interpret the equations in Einstein’s two theories. Physicists take them to be referring to spacetime because that is what their equations seem to describe. But it is possible to interpret those equations as referring to absolute space and time, even in the case of the general theory of relativity. And the reason for insisting on such an interpretation is that absolute space is required by the best ontological explanation of the natural world. That is the Pre-Socratic discovery that has been forgotten. Instead of merely inferring to the best efficient-cause explanation of what happens in the world, the Pre-Socratics were trying to figure out the best ontological explanation of what exists (as well as what happens) in the world. They were doing empirical ontology, and since ontology offers a deeper explanation of the world than science, empirical ontology is prior to physics. The atomists were right to insist on an ontology that recognizes both space and matter as substances.”

Hugh leaned across the table, as if he were telling me a secret. “That is, I suggest, the foundation from which new necessary truths can be proved. Its consequences are ontologically necessary. They follow from the best ontological explanation of the world, which is prior to empirical science, including physics, and all its theories about the efficient causes of what happens in the world. That is what I mean by doing philosophy in a new way. Instead of using epistemology to show that some truths are known with certitude, as traditional philosophy did, I am using empirical ontology to show that certain truths are ontologically necessary. They may not be certain, but they can be denied only by giving up the best ontological explanation of the world."

Hugh was speaking rapidly with an intensity that belied its importance to him, and I was beginning to sense that he was on to something beyond anything I could have imagined when he first made his casual comment about there being an absolute truth. It was no longer clear to me that he must be making some big mistake. I could not help responding, “Well, I suppose it is possible that space is absolute after all. In fact, I've always suspected that the paradoxes that Einstein left us with were not the final truth about space and time.”

There was surprise in Hugh’s face for the first time. “Wow! You do have an open mind, don’t you?” And then looking down, he added sadly, “You know, it’s not easy for physicists to consider this possibility. The relativity debate earlier in the century was so long and heated that they don't want to believe the issue is still open. No one defends absolute space any more, and it's taken for granted that there can be no reason for doubting relativity that doesn't come from predicting some new quantitatively precise measurement. Ontological arguments against Einstein's theories are seen as showing a preference for Newtonian intuitions over mathematical rigor. Pressing such arguments can get you expelled from graduate school in physics. This has gone on so long now that it is like an ideology. It's hard for physicists not to simply dismiss ontological doubts about relativity in anger, as if they were being pestered by a spoiled child.”

Hugh seemed to be dwelling on an unhappy memory, but when he glanced at his watch, he looked up at me with a combination of childlike hopefulness and anxiety. "I have something you might be interested in, if you see what I am getting at. I haven't the time to explain it all right now. But it’s all here." He opened his backpack and pulled out a thick pack of papers and handed them me. "Here is a diagram that represents this new, ontological way of doing philosophy and a manuscript defending it. You can do what you want with it."

The diagram had two main boxes, one at the top labeled FOUNDATION and the one beneath it labeled NECESSARY TRUTHS . It is the 'whole diagram' reproduced in the next section of this web site, and the main parts are included in the image here.

Inside the Foundation box, Hugh pointed to the three smaller boxes at the top which he said represented his three assumptions: (1) Naturalism, the belief that what exists is just what is in space and time; (2) Ontological Explanation, the belief that ontology is a kind of explanation which is deeper than efficient-cause explanations; and (3) the Empirical Method, the belief that the way to tell which theory to believe is by which is the best explanation of what we find in the world. These three assumptions, he said, lead to Spatiomaterialism, the belief that the world is made up of both space and matter as substances enduring through time. A line from the FOUNDATION box led to the other big box, labeled NECESSARY TRUTHS. Hugh explained that the recognition of spatiomaterialism as the best ontological explanation of the world is what demonstrates the new ontologically necessary truths about the world. They are what reason can know about the world from the vantage of this ontological foundation.

Those necessary truths were laid out under two main headings: one for theoretical reason containing all the conclusions about What Is, and the other for practical reason, with conclusions about What Ought To Be. Though both are ontologically necessary, he explained, the truths about the good are supported by those about the true in a way that resembles how both kinds of necessary truths are supported by the Foundation. The proof of necessary truths about what is not only solved all the problems that had arisen in the philosophy of mind, mathematics, and science, but also showed that evolution follows an inevitable course in the direction of natural perfection, leading stage by stage to rational beings like us. And the recognition of natural perfection is what resolved all the received philosophical issues about the nature of goodness, including the goodness of self interest, ethics and religion.

Each of the smaller boxes in both the FOUNDATION and NECESSARY TRUTHS represented arguments with several parts, and in each case there was a subdiagram depicting those more detailed logical structures. Pointing to the boxes, Hugh outlined for me all the major moves in his argument. Finally, he mentioned the manuscript itself, entitled "The Wholeness of the World," which he said explained in detail everything represented in the diagrams. It showed not only that absolute space is compatible with Einstein's two theories of relativity, but also how explaining physics ontologically made it possible to reduce theories in all the other branches of science to spatiomaterialism, solving major problems in every branch of science, social science and even the humanities. And it answered all the objections that have traditionally been raised against materialism by explaining the nature of consciousness, the nature of goodness, and how there could be something worthy of worship in a strictly natural world. The diagram was a road map to the manuscript, which carried out his new way of doing philosophy, he said, down to great detail in many cases.

I was curious. And it made sense, though I couldn't help also being more than a little doubtful that it did everything he claimed. Seeming more hurried now, Hugh said, "You might think of it as an inside-out encyclopedia. You know how ordinary encyclopedias inventory everything known by listing all the pieces of knowledge alphabetically. Well, in this encyclopedia, no alphabet is needed. Alphabetization is replaced by a diagram, the whole diagram. Everything reason can possibly know has a relationship to the whole, and that is how it can be located. The two largest boxes represent the two steps of the argument of ontological philosophy. The first, FOUNDATION, lays out what reason needs to assume in order to know that spatiomaterialism is true. The second, NECESSARY TRUTHS, lays out all the ontologically necessary truths about the world that follow from spatiomaterialism, including those that hold only of spatiomaterial worlds like ours, where the laws of physics are true. That is the framework in which all the contingent facts about the world are located, making it an encyclopedia of everything that reason can know. But two kinds of ontologically necessary truths are distinguished in the diagram, because the necessary truths about what ought to be are supported by the necessary truths about what is in much the same way as the Necessary Truths are supported by the Foundation."

"Ah, I see," I blurted out, "That is why you title it 'the Wholeness of the World.'"

"Yes, though there are other meanings. For example, in a more elemental and concrete way, 'the wholeness of the world' also refers to space itself, because space is a kind of substance that, by containing all the matter, can make a world whole. In a way, that is all that is really different in what I am saying."

Beginning to see what Hugh was getting at, I added helpfully, "And as an ontological explanation, it explains the world completely. Everything in the world is constituted by the basic substances, all the objects, the properties, and what happens. And I suppose it doesn't really matter that ontologically necessary truths can be known in a different way from contingent truths, since they are both true in the same way, I mean by corresponding to aspects of substances. That too could be 'the wholeness of the world,' I guess."

"Yes, that's another way it's whole. You might call it a God's Eye View of the world." Perhaps Hugh was encouraging me, like a teacher. "What gives us a God's Eye View is recognizing that space is a substance. We're so used to thinking of everything as being in space that it's hard for us to see space itself as an object. That's why 'substance' seems to mean material substance, as if it were self-contradictory to speak of space as a substance. But to get to the bottom of what exists, we must see space as well as matter from the outside, like an object. And we can do that by thinking of space as a substance. That is, after all, how God would have to have seen space in order to create the natural world."

"But these are not the only ways that the world is whole, at least, not a spatiomaterial world like our own, where the laws of physics are true. Another way is how language-using animals inevitably come to exist through evolution. That makes the world whole because they evolve the capacity to reason and eventually come to see how spatiomaterialism is the foundation of a explanation of necessary truths about the world. Hence, a part of the world inevitably understands the basic nature of the world, giving the world itself a reflective nature."

"Ah ha," I exclaimed, "that's why there's a little green circle labeled 'reason' toward the bottom of the whole diagram! It's the part of the world that knows about the wholeness of the world. You know, as a naturalist, it has always seemed to me that the world is somehow completed by our knowledge of it. The universe knows itself through us. But it would be even more perfect, if what the world wrought were beings with a complete understanding of world."

"Right. That's how it seems to me too. It means that reason comes to know everything represented by the whole diagram. But that can also be called wisdom. If philosophy is the love of wisdom, the whole diagram represents the structure of the wisdom that philosophy is the love of, both wisdom about truth and wisdom about goodness. It is wisdom about truth, because the FOUNDATION tells us not only what is true about the world, but also why the true is true. Truths of all kinds are true because they correspond to aspects of the basic substances constituting the world. But it is also wisdom about goodness, for not only does the ontological explanation of evolution and natural perfection tell us what is good. It also explains why the good is good. The good is good because it contributes to natural perfection. In both cases, the mark of wisdom is that both questions, what and why, are answered by the same property. The whole diagram represents such a two-level justification of both beliefs and intentions, That's how ontological philosophy can defend knowledge of a kind that is more fundamental than what people ordinarily claim to know. It is a wisdom worth loving."

Then Hugh looked me in the eyes and asked, "But, now, don't you see another way in which that would make the world whole?"

I felt like a student called on in class, afraid of not knowing his lesson. Suspecting that what Hugh meant must have something to do with how the whole diagram represents wisdom, I scrambled to put an argument together. "Well, if the diagram is about our world, it gives us a new way of doing philosophy. The wisdom it represents is our wisdom. We could use this way of knowing what is true and good in our world. So we could be certain about it. Is that what you mean? Does its certainty makes it the Absolute Truth?"

"Hold on!" Hugh leaned back, as if pulling on the reins. "Certainty is what epistemological philosophers expect of the Absolute Truth. They have to take the Absolute Truth to be something that cannot be doubted, because self evidence is what an epistemological foundation has to offer. But there can be no such certainty about ontological philosophy. The truth of its foundation depends on the world being constituted by the substances it says, and there is no way for beings like us to know about those substances except from information about the world, such as perception provides. With an empirical foundation, it is always possible that we are mistaken. There are, after all, experiences that would falsify spatiomaterialism. For example, material objects could start disappearing from one location at one moment and appearing at a distant location the next."

Feeling a bit defensive about my epistemological bias, I asked, "But how can the whole diagram represent the Absolute Truth without our being certain that it is true?"

"Well, there is another way of being sure of its truth, though its weight is felt only at the end of the argument. That is its completeness. An ontological explanation has a unique kind of simplicity, because it reduces everything to the same basic substances. And so if doing that explains everything in the world, it has a unique kind of coherence as a whole. There is no reason to doubt the best ontological explanation of the basic aspects of the world, if it also explains all the various kinds of phenomena that have seemed problematic and resisted explanation through the years, such as the fact that there are rational beings like us in the world, that we are conscious in the sense that it is "like something" to be one of us, why there is real difference between good and bad, and how there is something worthy of worship in the world. And there is further reason to believe it, if it shows not only the ontological necessity of many beliefs that were already recognized to be true, but also the ontological necessity of many truths that were not already believed, especially if the new ontological truths reveal a structure of necessity in which all the kinds of things found in the world have essential natures. The simplicity of its causes together with the all-encompassing scope of its conclusions about what is possible and what is necessary gives this ontological explanation the maximum coherence possible. What justifies the claim to certainty is that everything we know about the world fits together as a single system in the simplest possible way. You can't give up any one of its implications without giving them all up, for they all follow from the same simple ontology."

"That's certainly an excellent reason for believing it." Hugh was pointing to the kinds of reason that a naturalist like me could not dismiss, but I suspected him of trying to get away with something. "But surely you're not saying that there is nothing more to learn, are you? And if not, how can ontological philosophy be the Absolute Truth?"

"Because it's absolute in the relevant sense. Of course, there's more to learn, much more, including the details about the natures of the basic substances, which will eventually explain the strange astronomical phenomena, not to mention the details about the structure of natural perfection. By calling it 'absolute,' I am merely saying that nothing learned in the future will change the structure or content of the wisdom represented by the whole diagram. There is no equivalent theory that is as simple and comprehensive as ontological philosophy. No other conceptual system can do as well, because space and matter are the simplest basic substances that can explain all the basic aspects of the world. And unless physics is fundamentally mistaken, the necessary truths they entail explain all the kinds of things found in the world. There is no reason to accept conceptual relativism, or what contemporary Kantians, like Hillary Putnam, call 'internal realism.' Internal realism is the realism of science, and internal realists deride the possibility of 'metaphysical realism' by calling it the 'One True Theory' or 'God's Eye View' of the world. But the possibility of metaphysical realism is shown by ontological philosophy. That is the sense in which it is the 'Absolute Truth.'"

"So is that what you meant by a further sense of 'the wholeness of the world'? That ontological philosophy is absolute in a way that defies conceptual relativism?"

"Not quite! You were closer to the wholeness I was thinking of when you were pointing to the effect on our world of our coming to have the wisdom represented by the whole diagram. That wholeness is what the world comes to have as rational beings discover this ontological explanation of the world. Evolution in the direction of natural perfection makes it inevitable that beings like us come to exist in a spatiomaterial world like this one, and as they come to understand what is represented by the whole diagram, they will understand their own nature and their own place in the world. Since they will understand the nature of natural perfection, they will see how they can act for the good of the world as a whole, that is, besides doing what is good for themselves. And since they will also understand the nature of goodness deeply enough to see why it is good for them to do so, they will do what they can to make the world more perfect. Action guided by such an understanding of natural perfection is an essential part of the perfection of the world. That is the most complete sense of 'the wholeness of the world,' as far as I can see."

Looking into the distance, Hugh added, "You might say that such rational beings do God's work in the world. And if we were going to use those traditional terms, we could even call ontological philosophy a proof of the existence of God."

"So what you are saying is that Nietzsche was wrong about God being dead. Though God doesn't exist outside the natural world, the deeper truth is that God is being born inside nature through us."

"Well, if we're going to use traditional terms, it is more like pantheism. Though it is true that rational beings like us will be doing God's work when we act for the good of the world as a whole, the larger truth is that the world itself will be acting through us as its personal agent within space and time. After all, the existence of beings like us is a consequence of the basic nature of a spatiomaterial world like ours, the very same nature that is the source of purpose in the world, the source of a real difference between good and bad. So if you're looking for God, it is the whole world, not just a part of it. The perfection of the world is the most complete sense of 'the wholeness of the world.'"

Though he was clearly not a just true believer, I thought he was a bit too eager to get to such a happy conclusion, and so I tried puncturing his balloon. "But if God comes to exist in the world, where did the world come from? What caused the Big Bang?"

"Ah, that." Unfazed by my objection, Hugh leaned back and replied, "There was no Big Bang. That is one of the implications of using spatiomaterialism to explain the truth of physics. All the phenomena on which the Big Bang theory is based can be explained without denying that the universe is eternal. It is possible that the universe has always been pretty much like it appears now, infinite in extent and enduring forever. Instead of a Big Bang, there are more local events from which galaxies derive. 'Local big shrinks' is what I call them. The evolutionary process that has led to the existence of beings like us in our solar system occurs throughout the universe. It has always been occurring. And it will always be occurring."

Secretly, I admired his response. It had always seemed to me that grown men should be embarrassed to claim that the world came into existence from nothing. But I was still a long way from believing what Hugh said. "That is easy to say."

Hugh sensed that I had gone about as far I could go with him. "You've been very good about, hearing me out like this. There aren't many people who would, you know." He looked at me and went on, "I know this is a lot to take in at one sitting. And in this day and age, it's got to be hard to believe.”

"Well, I admit that it's an interesting idea. I can’t say that I’ve ever heard it before." Though I no longer doubted that Hugh meant "Absolute Truth" with a capital "A" and capital "T," I still wanted to keep a safe distance from it. "But don't get me wrong. I'm not saying I believe you. Far from it. I may not see what’s wrong with it now, but there are lots of issues. You know, Einstein, consciousness, goodness. Not to mention your claim that rational beings like us exist necessarily."

"Yes, of course. All that must be considered carefully." He paused and went on as if he were thinking of it for the first time. "It's not easy to take something like this seriously. Not talk about Absolute Truth. Even after you realize that it has nothing to do with Hitler or any kind of political absolutism that might enforce its authority by violence, it still has to overcome the stigma about claiming Absolute Truth that derives from the foolish way that Hegel defended Absolute Truth in his Encyclopedia of the Philosophical Sciences. But ontological philosophy is different from epistemological philosophy, and it might be better to think of this inside-out encyclopedia as a game. The whole diagram purports to represent a single, complete explanation of everything in the world that reason can know. So take it as a challenge. If you think you are sure that it is not true or somehow goes wrong, well, then, all you have to do is point out where. Identify some aspect of the world that it cannot explain, or even an aspect that it cannot explain as well as it is currently being explained. That will show that it is not the Absolute Truth. Or just show where the argument does not follow. Then, you can go back to your own business with a clear conscience. But what you will find, I predict, is that all those objections can be answered. It does hang together and it does explain everything better than what is currently believed. I don't believe that anyone can show that this new way of doing philosophy does not work."

Glancing at his watch, Hugh said, "I'm sorry. I’ve got to run now." Then, pausing to smile, he added, "I’ll leave you to eat your bagel -- if that’s what it really is."

We had been talking so intensely that I had barely reached the hole on one side. As Hugh rose from the table, I thought to ask, "But how can I get in touch with you?"

"You can't," he replied. "I'll have to get in touch with you." His bright smile then gave way to a more serious look. "But I am leaving the Wholeness of the World in your hands. Remember what I said. It's up to you what to do with it."

I don't know why he gave it to me, and considering how things have turned out, I wish I had been more curious. Perhaps it was just chance. The book Hugh saw me carrying was entitled, What Remains to be Discovered, a survey of the many questions that science can be expected to answer in the future. It was written by John Maddox, the longtime editor of Nature, a prestigious scientific journal, to show that the "end of science" had not yet come. And since Hugh probably caught on that I teach philosophy for a living, he may have seen me as someone on whom he could unload his burden. At the time, I still assumed that, despite the originality of what he was saying, Hugh would turn out to be a young man who fails to understand the magnitude of the obstacles facing intellectual culture at the close of the twentieth century. But having read his manuscript, I now realize that what Hugh gave me includes not only the explanations that Maddox thinks science will eventually discover, but more. Much more. In fact, what is surprising now is how little empirical scientists expect to know in the foreseeable future (though, in all fairness, I should mention that Maddox does see the importance of understanding the nature of space). But now that my doubts about Hugh's being a philosopher have vanished, I have nothing more to say about who he is, except to mention that his manuscript identifies its author as Hugh Renbircs.

I have found nothing in Hugh's argument by which I can reject it. It may well turn out that there are problems with certain parts of it, but I don’t see how any problem could be serious enough to derail the project as a whole. So ontological philosophy does seem to be a new way of doing philosophy. I am even warming up to the idea that it is the Absolute Truth. If it works, it can be seen as a proof of the existence of God, with all that that suggests. However, the judgment about it hardly depends on me. It depends on all those who consider it – as Hugh would no doubt insist, considering how his ontological philosophy explains the nature of reason. And only time will tell how that turns out.

Hugh made so much of the whole diagram as the key to the Wholeness of the World that I have decided to use the medium of the Internet to present it more or less as he presented it to me in person. That is a most efficient way to see what it is all about, and his argument lends itself to the new medium. The whole diagram is a spatial representation of the argument, and the interactive devices of web pages can use its spatial structure to bring out how everything in the world is explained by its relationship to the whole, that is, like an inside-out encyclopedia..

The diagrams start on the next page, with the “whole diagram” in the main pane of the window. If you click on a box in the whole diagram, you will be taken to a more detailed diagram of that part of the argument. And if you keep clicking, you will eventually be taken to the text of the argument itself. (There is a further layer of diagrams under Change which lays out the points about evolution.)

The left pane of each window is a navigation bar. The red labels are a Contents for the main chapters of the text, and when you reach the text, it can be downloaded for easier reading by simply clicking in the text pane and clicking print. The icons for the diagrams will take you to diagram pages, from which you can also proceed to the text. Clicking the icon for the Inside-Out Encyclopedia will bring you back to this introduction, and clicking the icon for tWoW will take you back to the entrance, the tWoW home page. (The entrance has a link to the Site Map from which you can also navigate to all parts of the argument, both diagrams and text, as well as links to various supplementary explanations of ontological philosophy.) As you may have found in getting here, it takes a while to load the main window at 28 kilobits per second. But after that, the diagrams and text pages load somewhat more quickly, and you can easily switch among them once they have been cached in your computer.

Once any diagram is up, however, there is quite a lot to explore before going the next diagram (or going on to the text), because I have put Hugh's brief explanations of the boxes in the diagram into labels that show up in the top frame of the main window whenever the mouse is hovering over them. That conveys the brief explanations of the argument he gave me.

The natural order of the argument, from premises to conclusion, is to start at the top of the whole diagram, considering the boxes in order from left to right (following out the implications of each), and then to proceed to the next row of boxes, where you do likewise. The text to which all these boxes refer is a single argument laid out from beginning to end in the traditional linear fashion. But if you are willing to grant what is shown in any box, you can skip that part (or consider it only as far you need in order to satisfy yourself) and proceed directly to the next box, until you get to the end. Thus, the diagrams make it possible for you to construct your own version of this argument, one that suits your needs. You may need to read only those parts of the standard text where you have doubts. And some people may follow the argument completely enough without having to read the standard text at all.

In any case, you can always see where you are located in the argument as a whole. The text is always accompanied in the top frame by a relevant diagram to nearby sections. You can see where you are in that diagram by letting your mouse hover over the nearest box in the text itself, for that will light up the corresponding box in the diagram. And you can see where that diagram is located in the argument as a whole by going back to the whole diagram. Thus, those who take up Hugh's challenge can use the whole diagram as an inside-out encyclopedia to isolate the part where you think ontological philosophy fails to be a new way of doing philosophy.

Can you say why ontological philosophy does not work? Is there some step in the argument that does not follow? Is there some aspect of the world that it does not explain? Without being able to point to some such failure, I do not see how anyone can dismiss it and still think of themselves as a philosopher. To dismiss it without an argument would be to give up the rational pursuit of truth and accept relativism, like the sophists.

Those who do find some reason for doubting that ontological philosophy works are asked to bring their objection here for all to see. Objections can be made publicly by joining the discussion of ontological philosophy at "onto-phil" (by sending to onto-phil-request@tWoW.net an e-mail with the sole text in its body: subscribe). Or you can e-mail me directly (webmaster@tWow.net).

In either case, I will acknowledge the argument and either refute the objection or show how a minor revision will enable ontological philosophy to work as a whole in the same way. If I cannot do that to the satisfaction of rational people generally, I will admit that ontological philosophy is a failure, terminate this challenge, and close the tWoW.net web site, so that everyone can go back to business as usual.

If you cannot find anything wrong with it, then I suggest that you carry Hugh's challenge to those who are supposed to know what is wrong with such arguments, such as teachers, professors, scientists, ministers and journalists – anyone who claims an interest in intellectual culture. Force them to tell you what is wrong with it, or else admit that they are sophists, who do not take part in the rational pursuit of truth.

In the end, it is up to you what is to be done about the wholeness of the world.

webmaster@tWoW.net

Phillip Scribner
Washington, D. C.
December 26, 1999

Foundation of Ontological Philosophy

Ontological philosophy is a new way of doing philosophy. Implausible though it may sound at this late date, after more than 2 millennia of trying, there is a new way of doing philosophy. And it is one that works.

Furthermore, since ontological philosophy is a form of naturalism that uses the empirical method, it is equally a new way of doing science. In other words, it unites philosophy and science. Not surprisingly, it has profound and far reaching implications.

Philosophy

Philosophy is different from ordinary ways of knowing. It aspires to a kind of knowledge that is prior to everyday reasoning, such as modern science and everyday practical reasoning. Since it takes a special foundation to defend a more fundamental kind of knowledge, foundationalism is the heart of philosophy. Ontological philosophy is a new kind of “first philosophy.”

In the past, philosophers have used epistemological foundations to argue for more fundamental truths. They used reflection on how we know to arrive at a theory about the nature of reason and knowledge such as the intuition of forms, certainty about ideas in the mind, and the language-users’ understanding of language. Such approaches to justifying a more fundamental kind of knowledge have failed, however, to garner general acceptance (mainly because they lead to metaphysical dualism and skepticism). Indeed, the failure of traditional, “epistemological” philosophy is one of the few points on which most contemporary philosophers can agree.

Ontological philosophy

It is not hard, therefore, to see why we might wish there were a new way of doing philosophy. And there is one. For it is possible to use empirical ontology (the acceptance of whichever ontology is the best ontological explanation of what is found in nature), rather than epistemology, as the foundation for justifying a more fundamental kind of knowledge.

By “ontology,” I mean a theory about the basic substances that constitute the world, where “substances” are self-subsistent entities that never come into existence and never go out of existence. That is what we implicitly assume when we take objects in the natural world to exist independently ourselves. They must be made of something that can exist on its own, or else they would depend on us. (And they must be related to one another in some way to exist together as a world.) To be the best ontology, as the empirical method requires, however, such a theory would have to postulate the fewest and simplest basic substances (and basic relationship) that can explain everything in the world.

Suppose there were an ontology that is demonstrably better than any alternative, including those offered by physics. And suppose that it entailed further propositions about the world that were not already recognized as true. Such an ontology would be a foundation for philosophy, for what else it implied would be ontologically necessary. Its implications could be denied only by giving up the best ontological explanation of the world. They would be ontologically necessary truths. Such truths would be more fundamental than and, thus, prior to what is known by ordinary means.

As it happens, there is such an ontology. It is “spatiomaterialism,” the theory that the world is constituted by space as well as matter enduring through time as substances. It is a better ontological explanation of the world than any alternative currently considered by naturalists. And it has many implications about the world that are not currently recognized as true, much less as necessary. It does what philosophy has always aspired to do.

The main reason that naturalists do not already accept spatiomaterialism is that they do not choose which ontology to believe by inferring to the best ontological-cause explanation of the world. Instead, they believe in empirical science, which infers to the best efficient-cause explanations of what happens in the world, and they accept whatever ontology is required for scientific theories to be true. The Einsteinian overthrow of the Newtonian belief in absolute space and time has led naturalists to assume that space cannot be a substance enduring through time. But, as will be shown below (under Change), it is possible to explain the truth of both Einstein’s special and general theories of relativity on the assumption that space endures through time (and, thus, is absolute). That is clearly a better ontological explanation of the world than ontologies derived from realism about theories in physics, because it is simpler and less puzzling than the belief that spacetime is what contains all the matter in the world.

Spatiomaterialism is also better than forms of materialism that take it for granted that bits of matter have spatial relations and that spatial relations can change over time, for it explains why they have spatial relations and how change is possible. Furthermore, since spatiomaterialism can explain the truth of all the other basic laws of physics, science offers no reason to doubt that it is true.

Empirical ontology affords, therefore, a way of doing philosophy that is not currently being considered. And as we shall see, it has many profound consequences.

Epistemological philosophy

Ontological philosophy is different from traditional philosophy, because philosophers have traditionally taken an epistemological approach. They tried to demonstrate more fundamental truths about the world than ordinary ways of knowing by taking as their foundation a theory about the nature of reason which was arrived at in some way by reflecting on how we know. Those truths were called “necessary,” but since the foundation was epistemological, rather than ontological, all that could be accomplished was to show that they are certain. In epistemological philosophy, what distinguishes necessary truths from ordinary knowledge is certainty (rather than being entailed by a deeper explanation of the world). Certainty is epistemological necessity.

To be sure, the systems constructed by the most ambitious epistemological philosophers had ontologies, and the claims they made about substances were supposed to be necessary. But these ontological truths were not ontologically necessary; they were truths about ontology that were supposed to be epistemologically necessary, or certain. That is because ontology is just an afterthought in traditional philosophy. The primary goal is to show the conclusiveness of the certain propositions about the world. But insofar as those necessary truths entailed theories about what exists, epistemological philosophers found themselves committed to some ontology or other. In other words, their ontological theories, or metaphysical systems, as they are called, were just implications of their epistemologically necessary truths, not their foundations.

Furthermore, these implications were unwelcome in the end, for their metaphysical systems inevitably cast doubt on their epistemological argument, leading to skepticism. Since success in epistemological philosophy comes from demonstrating that something beyond the epistemological foundation can be known (or so-called realism), it entails a problematic ontological dualism of some kind. In addition to whatever accounts for the existence of their epistemological foundation, epistemological philosophers find themselves committed to the existence of the other kind of substances whose reality they are demonstrating, and as it happens, it is never easy to explain how such different kinds of substances fit together as parts of a single world. Thus, realism leads by way of some problematic ontological dualism to anti-realism, or skepticism about the reality of what is supposed to be demonstrated, and the failure of epistemological philosophy is inevitable.

The foundation of ontological philosophy

Though ontological philosophy is based on ontology, rather than epistemology, it must also secure its foundation. That requires defending a specific theory about the nature of the world, and as mentioned above, the specific theory that will be defended here is spatiomaterialism. It cannot be justified by reflecting on how we know without reducing to epistemological philosophy. By calling it “empirical ontology,” I mean to suggest that it is justified empirically. Before saying what I mean by the empirical method, however, let me say a bit more about the other two assumptions on which spatiomaterialism will be justified.

Naturalism

The following defense of spatiomaterialism assumes that what is being explained by empirical ontology is the natural world. By the natural world, I mean everything in space and time. This is a form of naturalism, for it is to assume that the world is just the natural world.

This kind of naturalism is implicitly assumed by natural science. Naturalism is implicit in science’s commitment to the empirical method, for science has traditionally limited the evidence that is relevant in choosing among theories to observation, or what can be known by perception. Everything that can be known by perception is located in space and time.

Reflection, by contrast, has been excluded by the empirical method of traditional science. That has enabled science to set aside the reflection-based epistemological theories of traditional, epistemological philosophy. Ontological philosophy also relies mainly on perception.

But there is no principled reason to exclude reflection as a source of information about the natural world. Reflective subjects are, after all, parts of the natural world, and in the end, an ontology of the natural world will have to explain what is known about the world through reflection as well as what is known through perception. What is still excluded from ontological philosophy, however, is the use of reflection as a foundation for proving necessary truths. The foundation of necessary truths in ontological philosophy is the ontological explanation that best explains what is perceived. Only ontologically necessary truths are justified from its ontological foundation. As it turns out, however, spatiomaterialism puts ontological philosophy in a position to explain why it has seemed that some propositions can be known with certainty.

Ontological explanation

What makes it possible for empirical ontology to be used as a philosophical foundation is the recognition that ontology can be a kind of explanation. "Ontology" means, literally, "theory of being." It is a theory about the nature of existence, and ontology can be explanatory, if existence can be reduced to basic substances and how they exist together as a world. That is to assume that substances, as substances, are self-subsistent entities. Since basic substances exist on their own, each distinct from all other substances in the world, it may be possible to explain everything in the world by showing how it is constituted by basic substances of certain kinds with a certain basic relationship to one another.

For naturalists, the world in which everything is to be explained ontologically is the natural world, or what is found in space and time. But to explain everything in such a world is not merely to explain the existence of the objects in space. It is to explain all their properties, their relations to one another, and how properties and relations change as time passes. In other words, the natural world can come down to a few basic kinds of substances related in certain basic ways only if that can explain everything in the natural world and everything about the natural world. The inability to explain the possibility of some aspect of the world would show that the world is not constituted by the basic substances and relationships postulated by the ontology.

Empirical method

When ontology is understood as a kind of explanation, it is possible to use the empirical method to choose which specific ontology to believe. By the empirical method, I mean the method used by science. I assume that that method is basically an inference to the best explanation of what is found in the natural world. Thus, by empirical ontology, I mean the project of inferring to the best ontological explanation of what is found in the natural world.

No attempt will be made to justify the empirical method. Justifying the empirical method is a road traveled by traditional philosophy, and ontological philosophy takes a different road by simply using the empirical method, as science does. This way of judging between conflicting theories is what beings like us do naturally. (Later, when we take up necessary truths about evolution, we will trace that disposition to the function of the brain and how the brain works.)

Our main departure from empirical science is, therefore, to apply the empirical method to ontology, rather than just to theories about efficient causes of what happens. That is, we shall be deciding what to believe about the nature of what exists in the world, rather than only what to believe about the causes of what happens there.

More precisely, we shall infer to the simplest and fewest basic substances (and basic relationship among them) that can explain everything in the world, that is, every kind of object in the natural world and every aspect of the natural world, including those which have to do with how things change over time.

Ontological science

Empirical ontology affords, therefore, a way of doing philosophy that is not currently being considered. It is equally, however, a new way of doing science, because ontological philosophy is tantamount to recognizing ontology as a more basic branch of natural science than physics. That means that the basic substances (and basic relationship) discovered by empirical ontology must be able to explain the truth of all the basic laws of physics, much as physics has often been thought to explain the laws of less basic branches of science, such as chemistry and biology. But that does not mean that science is any less empirical, not as long as ontology also uses the empirical method. Nor is this a trivial or meaningless change in science, for it makes all the explanations of less general sciences reducible to the most basic branch of (ontological) science.

Ontology is not, however, quite like other branches of science, because its uses substances, rather than laws of nature, to explain what is found in the world. That is the difference between ontological-cause explanations and efficient-cause explanations. Efficient-cause explanations depend on laws of nature to connect efficient causes to their effects, and accordingly, to infer to the best efficient-cause explanations is to attempt to discover the simplest and most comprehensive laws describing the regularities found in nature. But the causes in ontological explanation are the basic substances and the basic relationship among them, and since things are explained ontologically by showing how they are constituted by substances, ontological explanations do not depend on laws of nature. Ontological explanations show how basic substances are identical to what is found in the world. And since the laws of nature are explained ontologically (by showing how the basic substances and relationships postulated by the ontology make the laws true), the explanations given by ontological science all cite substances as causes in the end.

It is now widely recognized that laws in less general branches of science are not reducible to the laws of physics. But as we shall see, when empirical ontology is seen as the most basic branch of natural science, it is possible to reduce not only the basic laws of physics, but also the laws of all the less general branches of natural science, including biology, physiology, and the social sciences, to the best explanation in the most basic branch of science.

To be sure, it is an ontological reduction, rather than scientific reduction (or reduction to the laws of physics). But in “ontological science,” all the theories of the less general branches of natural science can be reduced to the most basic branch, accomplishing a great unification of scientific knowledge.

That is how empirical ontology unites philosophy and science. But a difference between them can still be discerned because of their different interests. While philosophy sees empirical ontology as a foundation for defending ontologically necessary truths about the world, science sees it as a way of explaining the truth of theories in physics and other branches of science.

That is, the recognition that ontology is a more basic branch of empirical science than physics introduces the project of discovering the simplest and fewest kinds of basic substances that can explain the truth of the laws of physics. That is spatiomaterialism, and combined with the truth of the laws of physics, it entails the ontological necessary truths by which all the theories in less general branches of science are reduced to a simple ontological theory.

The Wholeness of the World

The reason for calling this philosophical argument “the Wholeness of the World” is that spatiomaterialism explains everything in the world. As an ontological theory, spatiomaterialism must be able to account for (in the sense of explaining the possibility of) everything found in the world, including not only all the objects in space, but all their properties, relations and how they change. But it can lead to new beliefs about the world only by demonstrating ontologically necessary truths about the world. In some cases, what is new is just recognizing the necessity of what is already believed to be true, but in other cases, the beliefs themselves are new. It is the completeness of its ontological explanation in this latter sense that earns this argument the title, "the Wholeness of the World." Once spatiomaterialism is elaborated in a way that can explain why the basic laws of physics are true, its implications hold in every possible spatiomaterial world like our own, and those ontologically necessary truth explain the nature of the world in a most complete way. How complete it is can be suggested by mentioning that it explains all the puzzling phenomena that seem to lie beyond the limits of science and have raised doubts about naturalism, including consciousness, goodness, and even how there can be something worthy of worship, or holiness, in a strictly natural world. What makes this possible are its implications about the nature of evolutionary change, and the completeness of this theory of evolution is evident in how many organisms in our world turn out to have essential natures, including not only plants and animals, but also subjects like us who come to know that the world is whole in this way. But it will not be possible to explain fully what all is meant by “the wholeness of the world” until the conclusion, because its various aspects fit together in a way that makes the world even more whole than can be seen at first.

Insofar as it is a complete explanation the nature of the world, it is not merely an explanation of the world. It is the explanation of the world. That is the sense in which it is the Absolute Truth. This is to deny the conceptual relativism of contemporary kantians, like Hillary Putnam, because there is no other theory that can explain everything in and about the world as simply as one based on spatiomaterialism. Ontological philosophy is the "metaphysical realism," the "One True Theory," and the "God's Eye View" of the world whose possibility is denied by such so-called internal realists.

Naturalism

Naturalism is the first assumption of ontological philosophy. It is the belief that the world is just the natural world. By the "natural world," I mean the world disclosed to us by perception, the world where we find ourselves, each having a body alongside others as parts of a world of objects in space that move and interact over time. That is the world of our daily lives.

It is the world to which we are all referring when we speak to one another, as language-using animals, about ordinary matters. We refer to objects in space, attribute properties and relations to them, and explain what happens to them. But some of the objects in space are also subjects, like ourselves, and we describe them in a special way. To them we attribute intentions, desires, thoughts, beliefs, perceptions and other subjective (or psychological) states. They are known by reflection, rather than perception (though knowing about the subjective states of others usually depends on perception as well). But that does not mean that subjective states are not parts of the natural world. They are parts of the natural world because they are states of beings like us, who exist as animals in the natural world. The natural world includes, therefore, not only what is known by perception, but also what is known by reflection.

What exists

The role of naturalism in ontological philosophy is to identify what needs to be explained, and for that purpose, it is appropriate to understand it in terms of its implications about what exists and what does not exist.

Positively

Positively, naturalism is the belief nothing exists but what is located in space and time. All the objects we perceive are located in space. Indeed, they are all related to one another as parts of a single world, since all the locations in space are connected to one another continuously in three independent dimensions. But objects can also move and interact with one another, and the events involving them are also parts of the same world, because all moments in time are connected continuously in a single dimension.

Though naturalism assumes that whatever exists is located in space and time, that does not mean that whatever has a location in space and time exists. Though events in the past and future have locations in space and time, they may not exist. Whether they do or not depends on how we resolve a profound ontological issue about the relationship between existence and time. We must decide whether to believe that existence itself is in time, so that only the present moment exists (or "presentism"), or to believe that time is just another kind of relation, like space, which holds among the things that exist. (See Ontology: Temporality and Spatiomaterialism: Time.)

Negatively

Space and time are so inclusive that naturalism may seem to be obviously true, but the significance of this assumption comes into better focus when we consider it negatively. For naturalism is also the denial that anything exists outside space or time.

God

God, for example, is supposed to exist outside both space and time. That is, at least, what traditional theists (and deists) must hold, for they believe that God is the creator of the natural world. (Nor is God part of the natural world by virtue of being ubiquitous, for that means existing everywhere in space at once, and if that were how God exists, He would be space.) Belief in a creator-God is a kind of supernaturalism. In fact, that is what was being scorned by those who first called themselves "naturalists" in the eighteenth century. They expected to be able to explain everything in the world without appeal to anything outside nature, and that negative sense of "naturalism" is what is intended here.

Forms

It is not just God, however, that naturalism denies. Neither are there any Platonic Forms. Plato held that there are objects knowable only by reason, such as mathematical objects, justice, and the nature of human beings, and even The Good Itself, which exist independently of the natural world. By that he meant that they existed not only outside space, but also outside time, for he he described it as a Realm of Being, opposite in nature from the Realm of Becoming, or nature.

Plato's main reason for postulating the Forms was to explain the nature of goodness objectively. He held that all the other forms follow from The Good itself, making them, and what participates in them, good. But this motive for believing that something exists outside space and time now generally takes the form of the belief in a supernatural God. Platonism is still defended, however, in the philosophy of mathematics. For example, numbers are supposed to be abstract objects. But since what makes them abstract is that their existence is not supposed to depend on anything located in space and time, naturalism must deny their existence.

Minds

Minds are also denied by naturalism, if they exist outside space, as the tradition of modern philosophy would have it. Though Descartes assumed that minds are in time, he denied that they are in space. (He argued that mind has a unity that precludes its being extended, which he took to be the essential property of objects in the natural world. Thus, he believed that mind is an opposite kind of substance from body, with mind and body existing independently of one another.) Insofar as minds are supposed to exist outside space, naturalism must deny their existence.

Problems

Naturalism holds, therefore, that there is nothing to be explained but the natural world. However, that does not mean that it can simply deny the existence of Cartesian minds, Platonic Forms, a transcendent God, and whatever else is supposed to exist outside either space or time. Naturalism must explain everything in space and time, and in each case, certain natural phenomena have led people to believe in the existence of these supernatural entities. Though those phenomena may depend on reflection, not just perception, they are clearly part of the natural world, for they occur to subjects like us in space and time. Thus, like everything else in space and time, they need to be explained.

Consciousness

What makes the mind seem immaterial is consciousness, that is, the way in which whatever we experience has an appearance to us. When we perceive a green leaf, for example, the color of the leaf has a certain intrinsic quality, and even though that quality seems to be located in the leaf, it has an appearance to us which we could not explain to someone who was blind from birth. The same holds not only for other colors, but also for sounds, odors, tastes, and bodily sensations of all kinds. These peculiar objects of reflection are called "phenomenal properties," "qualia," "raw feels," or the like, and they abound in normal perception. In perceiving the leaf, for example, we see many green qualia as covering its surface along with color qualia of other kinds on its stem and other nearby objects. Other kinds of sensory qualia seem to make us aware of its odor, its coolness, its taste, and the like. Each simple phenomenal property seems of have a certain location in space relative to the others at the time, and in the case of bodily sensations, such as itches and pains, they seem to have a locations in some part of the body which, in turn, is located in some part of the same phenomenal space as other objects of perception. Much the same kinds of appearances occur to us in remembering, imagining, and any kind of thinking about objects in space, though they are fainter, less distinct, and not always as spatially coherent. Indeed, even emotions, abstract thoughts, and other mental events have appearances for the subject to whom they occur.

This fact about experience is what will be meant here by "consciousness." Consciousness can make it seem that the conscious subject is not just an object in space, not merely a body alongside other objects in space, because each subjective state involves the appearance of many different kinds of qualia (or simple phenomenal properties) to the subject at the same time. This is the unity of mind to which Descartes pointed in order to show that mind is a basically different kind of substance from body. It means that mind cannot be cut up or divided into parts like extended objects in space. In other words, consciousness is not located in space, like a material object, but rather seems to contain a space of its own, because each sensory qualia appears to have a spatial location relative to all the others, as in the colors that appear to be on the surface of the leaf or its stem. Descartes called these appearances "ideas" and the subjects to whom they appear "minds," but the natural phenomenon to which he was pointing is the fact that there are such appearances to beings like us: qualia of many kinds all have locations in a phenomenal space, which is distinct from the space in which material objects exist.

The essential difference between mind and body led Descartes to believe that mind is a substance that is not located in space at all. Being indivisible, mind could not be part of extension, and thus, it was supposed to be an immaterial substance. Naturalism must deny that there are any minds in that sense. But to be credible, naturalism must somehow explain consciousness as a natural phenomenon. For we are certainly parts of the natural world, and it is hardly plausible to deny that we are conscious.

Goodness

If naturalism could explain consciousness in beings like us, it might seem that there would be nothing left to explain about Platonic Forms, because the abstract objects that appear to the experiencing subject in reasoning could be explained in the same way as ideas in the mind. (An explanation of abstract entities is, in any case, rightly demanded of naturalists, and brief statement of the one given here can be found in Relations: Ontological theory of mathematical knowledge.) There is, however, another aspect of the phenomena that led Plato to believe in Forms that would remain unexplained. Plato believed in the existence of Forms not merely because they are objects of rational intuition, but also because he believed that they are ideal and that things in nature are striving to be like them. That was his theory about the nature of goodness. Just as we try to be virtuous human beings, natural objects strive to be like their Forms, because the Forms are good.

Not only Platonists believe that there is a real difference between good and bad. It seems obvious to many people that goodness is something about the object, state, or event that makes it so that it ought to exist, whatever we may believe about it. For example, what makes an action morally right or wrong for beings like us is something about the action itself that makes it worth choosing, not just something we may believe or feel about it. Thus, goodness is also an aspect of the world that naturalism must explain.

The first attempt to explain goodness naturalistically was made by Aristotle. He thought that every natural object (as opposed to artifact) changes on its own for the sake of attaining an end, or final state, which is the fullest actualization of its essential form, and he explained this phenomenon by holding that there are "final causes" at work in the natural world along with efficient causes. For example, the acorn grows into an oak tree because the final cause of its natural kind is to be a mature oak tree. Growth and development are due to what is called "final causation." Aristotelian teleology, as it is called, explains how goodness is something objective by postulating a special kind of "force" in nature.

The belief in final causation was decisively rejected by most naturalists with the rise of modern science in the Renaissance. Modern science began with the discovery of laws of nature by which events in nature can be predicted, and explanation by such efficient causes was so obviously explanatory that, by contrast, explanations by final causes had to be rejected as merely descriptions of phenomena which call for explanation by efficient causes. Thus, teleology was rejected by naturalists. Nor could they reconcile the belief in final causes with their new found mechanism by holding that natural objects are designed to work mechanically toward certain ends, because that way of explaining the objectivity of goodness required them to believe in a God who created the natural world.

Many naturalists believe such that a naturalistic explanation of the difference between good and bad has been given by Darwin's theory of evolution. Darwin showed how organisms acquire traits that seem to be directed toward ends as a result of the natural selection of random variations on their heritable traits as the organisms succeed in reproducing. That explains why organisms seem to be changing in the direction of ends which are good for them. Thus, the difference between good and bad does not depend on how we feel about it. And Darwin's explanation involves only efficient causes. Thus, it is sometimes seen as the reduction of teleology to efficient causes.

However, most of those who believe that there is a real difference between good and bad and between right and wrong are not satisfied with the Darwinian explanation because of its accidentalism. As contemporary Darwinists understand it, natural selection is caused by external changes in the environment, which are inherently unpredictable, and that makes what evolves far too accidental to explain the difference between good and bad that is objective in the sense that they mean. (For a discussion of its accidentalism, see Change: Accidentalism.) They will insist that there is more for naturalism to explain about this phenomenon before they will be convinced that the world is just the natural world. Teleology is, therefore, still a problem for naturalism.

Holiness

Again, however, it might seem that if naturalism could give an adequate explanation of the objective difference between good and bad, it would not be necessary to explain the belief in God. God has been the traditional foundation for explaining why good is different from bad, for it is supposed to come down to his inscrutable purpose in creating the natural world. But even if there were a naturalistic explanation of the difference between good and bad, many who believe in God would not be satisfied, because what they believe in is not just that there is an objective difference between good and bad. They also believe that there is something worthy of worship, something so inherently good that we ought to accept it as the highest good, submit our wills to it, and treat it in a uniquely reverential way, that is, as something sacred or holy. The faithful believe that they have experiences of a kind that reveal the actual existence of such a thing to them, and the universality of religion among the cultures of the world makes this a phenomenon that must also be explained by naturalism, even though it denies there is any God existing outside space or time.

One way for naturalists to explain consciousness, the belief in a real difference between good and bad, and the sense that there is something in the world worthy of worship is to deny the reality of these phenomena. Naturalists can hold, in other words, that their critics are simply mistaken in how they describe these phenomena -- that what is being referred to is something quite different from what they believe.

Consciousness might be dismissed as a belief that results from a linguistic confusion (such as the belief in a "private language" or the acceptance of "folk psychology").

The belief in a real difference between good and bad might be explained away as a mere projection of our subjective feelings onto the world (in much the same way as objects in nature seem to have the colors and other phenomenal properties that are just ideas in the mind).

And the belief in something worthy of worship might be explained as simply what is feels like to submit to a higher authority.

Naturalists have given such explanations in the past. But they have not convinced those who take these phenomena to be real, and thus, naturalism has rightly been treated as just one possible view of the world among others. Though naturalism may be plausible to many people without an adequate explanation of these phenomena, there is good reason to doubt its truth as long as these explanations are not accepted as adequate by those who appeal to these phenomena. Theists, mind-body dualists, and those who believe in objective goodness are rational beings too, and if naturalism is a reasonable view, it should be reasonable to them. Thus, the burden that naturalism must bear is rather large. It must be able to explain everything in the world, including these problematic phenomena, to the satisfaction of every rational being, including those who have been led to believe in entities existing outside space or time — that is, as long as they are willing to give reasons and not just be arbitrary and dogmatic in their assertions about what exists.

Ontology

The second assumption of ontological philosophy is about ontology. Ontology is, literally, the study of the nature of being (or existence), and what we shall assume is that ontology is a kind of explanation.

Ontological philosophy takes ontology to be a kind of explanation in which the causes are basic substances (along with their basic relationships to one another), and the effects are what is found in the world, or all the phenomena. Given the existence of certain kinds of basic substances and basic relationships, it explains the things found in the world by showing how their existence is constituted by such substances and relations among them.

If ontology is a valid kind of explanation, an adequate ontology should explain everything found in the world, for it is a theory about the nature of existence and what we mean by "the world" is everything that exists. To assume that ontology is a valid kind of explanation is to assume, therefore, that everything found in the world can be explained by showing how its existence is constituted by basic substances, given how they exist together as a world — including all the objects in the world, all their properties, all their relations to one another, and every way that they can change. It holds, in other words, that nothing exists, ultimately, but the basic substances.

The other way of doing philosophy is based on epistemology, and for epistemological philosophy, ontology is something quite different. Ontology is simply a thesis about what exists. Epistemologists base their claims about certain truths being necessary relative to our ordinary ways of knowing on a theory about how we know. Thus, they find themselves committed to the existence of entities of all the kinds that are known, including the entities presupposed by their foundation as well as all the additional entities entailed by their conclusions (assuming that they succeed in defending those conclusion). Since it is committed to the reality of additional entities of some kind, its ontology is called "realism." It is the belief in the "reality" of those additional entities. But since, as it turns out, they never fit together intelligibly with the entities constituting the epistemological foundation, realism is a form of ontological (or metaphysical) dualism that engenders skepticism. Hence, realists have always had to do battle with so-called anti-realists, who accept only the entities presupposed by their epistemological foundation. To mark how this view of ontology differs from ontological philosophy, let us call it "ontology as realism."

Ontology as a form of explanation

For ontological philosophy, ontology is explanatory. We assume that a certain kind of explanation is valid, which is to believe that there are causes and effects of certain kinds. In this case, the causes are the basic substances and their basic relationship to one another, and their effects are what they can constitute, which includes, if adequate, everything that can be found in the world, including all the objects, their properties and relations, and how they change over time.

Ontological causes

To see how such effects are produced ontologically, let us consider, first, the nature of the causes, both the substances and their relations, and, then, their effects.

Substances

Substances are one part of every ontological cause, and in order to explain how they help produce effects, we must consider both the nature of substance itself and a relevant difference among the kinds of basic substances that may be postulated by an ontology.

Nature of substance

Substance, we shall assume, has a nature that includes to two basic aspects. For something to be a substance, it must not only have a certain determinate nature, but must also be self-subsistent. That is, a substance must have, as a substance, both an essential aspect and an existential aspect to its nature.

Essential aspect of substance. A substance must have an essential aspect to its nature as substance, because in order to exist at all, it must exist in a determinate way. It is not possible for anything to exist without existing in a determinate way; indeterminate existence would be tantamount to nothing existing. The essential aspect of a substance includes all its kind-differentiating properties that do not change as time passes.

To assume that substance as substance has essential properties is not to assume that properties exist in addition to the substances that have them. We can and shall assume that properties are simply aspects of the substances themselves. Thus, essential properties are simply how substances exist, implying that substances can exist in different ways, as in substances being of different kinds. Beings like us can think about aspects of substances and distinguish their aspects from one another, and when we do, we are thinking about their properties. But ontological philosophy cannot answer questions about how rational beings have the ability to think about the aspects of substances as distinct from the substances themselves until it has explained the nature of what exist and the existence of beings in the world, like us, who can think at all. (See, for example, Change:Abstract Objects, or for a briefer statement of the entire theory about the nature of reason, Relations: Ontological theory of mathematical knowledge.

We will take up the kinds of basic substances after explaining the nature of substance as substance.

Existential aspect of substance. Substances also have an existential aspect to their nature as substance. They must, because, in an ontological explanation of the world, it is the existence of substances (in certain relations) that explains the existence of what is found in the world. Substances are, in other words, self-subsistent.

Existence is, therefore, a property of substance as substance, just as having an essential aspect is. But in both cases, these aspects of substances have to do with their having aspects. The essential aspect is that they have an aspect of the kind we will call their "essential nature," and the existential aspect is that what has such an essential aspect exists independently of the rational being who know about them. That there are aspects of substances that have to with their having aspects is no more puzzling than that they have aspects at all and is answered in the same way, as we shall see, by the ontological explanation of the nature of reason. (See Stage 9, Rational Spiritual Animals, under Reproductive Global Regularities under Change.

There are, however, two aspects to the existential aspect of the nature of substance as substance: particularity and temporality.

Particularity. First, substances are self-subsistent in the sense each substance has an existence that cannot be reduced to the existence of any other substance or substances in the world. Each substance exists on its own. That is not to say that substances must be able to exist even if all the other substances were to drop out of existence. (For example, it may not be possible for material substances, given their essential nature, to exist without having spatial relations to other material substances.) It is merely to say that there is something in the world whose existence would not be accounted for if only all the other substances in the world were assumed to exist. In short, each particular substance has an existence that is distinct from every other substance in the world.

We must accept that substances are related to one another in one way, at least, since we are assuming that there is more than one substance in the world. By "the world," we mean everything that exists, and thus, if there is more than one substance in the world, the world is a whole composed of parts. Since every substance is, by virtue of the existential aspect of its nature as a substance, something that exists, each substance is a "particular" substance in the further sense of "being part of the world." Each substance has a relationship to the world as a whole, and since it has an existence that is distinct from every other substance in the world, it also has a relationship to the other substances as a different part of one and the same world with them. In other words, when we postulate basic substances, we assume that they are parts of one and the same world.

There is another relationship that all substances have, namely, being identical to themselves. Relationships, like properties, are not something in addition to what has them, but merely an aspect of the substances that have them. And we continue to put off discussing how beings like us know about relationships until we explain the nature of reason ontologically. Although identity is a relationship, it is a relationship that something has to itself, and thus, it may be considered another aspect of each substance taken separately, like its properties. That is, each substance is identical to itself.

By the way, this is to assign ontological meaning to each of three basic senses of "is." "Is" can be used to say that something exists, and in that sense it refers to the property of existence, or the existential aspect of substance as substance. "Is" can also be used as a copula, to attach a predicate to a grammatical subject. In this case, it is referring to the relationship between a substance and some aspect of it, either a property that characterizes its essential nature or one that characterizes a changeable aspect of it (such as the roundness of a piece of wet clay). Finally, "is" can be used to assert identity. When identity is asserted of two substances, it says that the two substances have the same relation to one another as each has to itself, that is, that they are identical. But when identity is asserted of aspects of substances, that is, of properties, it has a different meaning, because different substances can have the same aspects and be of the same kind under each aspect. For example, all substances have the existential aspect, and "being" is the same property in each case. Likewise, substances of the same kind have the same essential properties. It will be possible to keep track of which properties are identical and which are different, because one thing an ontology provides by explaining everything in the world is an inventory of all the aspects of substances.

Temporality. Second, we assume that substances are self-subsistent in a temporal sense. Substances do not go out of existence over time, nor do they come into existence. Thus, a substance that exists at one moment must have existed at the previous moment. And it will continue to exist the next moment. Thus, if a substance exists at all, it exists at every moment in the history of world. It is permanent. The substances that exist at any one moment are the same substances that exist at every other moment in the history of the world.

This is a strong assumption to make about the nature of substance as substance, and it is not one that has always been made, even by naturalists.

According to Aristotle, for example, substances come into existence and go out of existence over time in a process of generation and corruption, though he did assume that they also had "material causes," or matter, that endures through change.

Other naturalistic ontologists do not postulate substances at all, but only "tropes," or properties considered as particular entities. Though tropes are supposed to explain everything in the world, they are not substances in our since, for they are supposed to come into existence and go out of existence at determinate locations in space from moment to moment. See Williams.

Though ontological philosophy makes this strong assumption about the temporal aspect of the existential aspect of substance as substance, there is an issue about the temporal aspect that we will leave open for the time being. To hold that substances never come into existence nor ever go out of existence over time is to presuppose that they are in time. That is, time is built into the nature of substance, as part of the existential aspect of the nature of substance as substance. But there are two different views about the nature of time and how it is related to existence. One is the "endurance" theory and the other is the "perdurance" theory.

Endurance theory of time. The first view holds that substances endure through time. This theory assumes that existence itself is in time. That is, only the present exists. The past and the future do not exist. Thus, for a substance to exist at all is for it to exist at the present moment. This view is also called "presentism." But since substances never come into existence, every substance must have existed at every past moment in the history of the world. And since they never go out of existence, every substance will still exist at every future moment in the world’s career. In other words, substances are identical through time: each substances that exists now is identical to some substance that existed or will exist at every other moment in the history of the world.

Since endurance theory assumes that the past and the future do not exist, they must explain the sense in which statements about the past and the future are true. It holds that such statements are true of substances that exist now, though the properties being ascribed to them have to do either with what has happened or with what will happen to them. That is, the aspects of substances which exist now include the states they had in the past and the states they will have in the future.

Perdurance theory of time. The other view is that substances perdure across time (or over time). Instead of assuming that existence is in time, this theory holds that time is a relation that holds among parts of substances. On this view, the past and the future exist in the same sense as the present. Though perdurance theorists can agree that substances never come into existence nor go out of existence over time, what they mean is that each substance is made up of a continuous series of moments stretching all the way back and all the way forward in the temporal dimension. Thus, instead of seeing substances as identical through time, they see substances as involving a part-whole relation: each substance is a whole whose parts include its state at every moment in its history. Thus, corresponding to the part of each substance that exists at any one moment, there is another part at every other moment in the history of the world.

The distinction between the endurance and perdurance theories about the existential aspects of substance as substance can be traced to McTaggart, who argued around the turn of the twentieth century that it is self-contradictory to hold that only the present exists. But recently, it has been resurrected by analytic philosophers defending the so-called "tenseless theory of time," as opposed to the "tensed theory of time". (The tenseless theory holds that statements about the past, present and future can all be translated, without any loss of content, into sentences about the relations of moments in time that hold eternally, whereas the tensed theory insists that some content is lost, namely, what they imply about which moment is actually present, that is, not just present relative to some particular time of utterance. See Oaklander and Smith.) And even more recently, the perdurance theory has been defended, albeit without admitting it, as what is called "four-dimensionalism" against "three dimensionalism." (See Sider.) But the reason I leave the issue open here is because a similar view is currently accepted by naturalists who are trying to be realists about the notion of spacetime introduced by Einstein’s special and general theories of relativity. Spacetime taken ontologically entails the perdurance theory.

Since purdurance theory assumes that all moments in the history of the world are ontologically equivalent, it holds that statements about the past and the future are true in exactly the same sense as statements about the present. There is no need to hold that statements about the past and the future are really about substances that exist now.

Whatever the relationship between time and existence, the temporal aspect of the existential aspect of substance involves a relationship between moments in time. Everyone agrees that moments occur in a continuous series, though endurance theorists think of time as flowing from the past into the future, and perdurance theorists think of time as just an order about the moments that all exist. But since endurance theorists take existence itself to be in time, they take time to be as ontologically basic as existence and substance, and thus, they take temporal relations to be a measure of the separation between different moments in the existence of a substance that is identical over time. Perdurance theorists, on the other hand, take all the moments in the history of a substance to exist in the same way, and thus they explain time, in effect, as how these moments exist together as a substance in the world.

The difference between these theories can be seen in what they imply about change. In a world where substance is permanent, what changes are the properties or relations of substances, or aspects of them. Endurance theory holds that change involves properties or relations coming into existence or going out of existence over time, because if the future and the past do not exist, there is no "place" for them to come from or to go to. On the other hand, perdurance theory holds that properties and relations never come into existence and never go out of existence, because if the future exists, the properties and relations already exist before the change takes place. And if the past exists, the properties and relations continue to exist after the change is long over.

Kinds of substances. The substances that an ontology postulates are the causes by which it explains the world. But in order to explain completely what is found in the world, those substances must be the most elementary substances that constitute the existence of things in the world. Let us call such ultimate parts of the world "basic substances."

All substances have, as substances, the same kind of existential aspect, but the essential aspects of their natures may be different. Thus, there may be different kinds of basic substances making up the world. But it is important to recognize at the outset that the essential natures that distinguish kinds of basic substances from one another may be either temporally simple or temporally complex.

We are assuming that the properties that characterize basic substances are simply aspects of them. The properties that characterize the essential nature of a substance are aspects of the essential aspect of their nature as substance, and they distinguish one kind of basic substance from another. Such essential properties do not change over time

Temporally simple. Now, a substance that exhibits its full nature at each moment is a simple substance. That is, a substance will be said to have a "temporally simple essential nature" insofar as its essential properties are aspects of it that exist complete at each moment in the history of its existence. The contrast to complex substances will make this clear.

Temporally complex. The essential nature of a substance may also be defined by how its properties change over time. Properties that can change over time are contingent (or "accidents"), but if contingent properties always change in the same way, the way in which they change may be an essential property. For example, the properties a substance exhibits at one moment may depend on the properties it had the previous moment (together with its relations to other substances), and since the regularity about how they change would be a property that the substance has at every moment, it would be an essential property of the substance. But its essential nature would be dispositional. Insofar as the essential aspect of the nature of a substance is defined by a regularity about how its contingent properties (or relations) change over time, it will be said to have a "temporally complex essential nature."

Relations

Substances are only one part of every ontological cause. The other part is the relationship that holds among the basic substances. Relations are necessary for ontological explanation, because substances have nontrivial ontological effects only by working together, that is, by combining with one another in some way to constitute the existence of things found in the world. What makes ontological explanation explanatory is that substances can work together in different ways to produce different effects.

We must assume, therefore, that there is more than one substance in the world. Though it is conceivable that the world is made up of a single substance, nothing in such a world could be explained ontologically, in our sense, for everything found in such a world would be the same as what is assumed by the ontology in postulating that single substance.

Spinoza was not, therefore, giving an ontological explanation of the world in our sense, because according to his Ethics, he assumed that a single substance makes up the entire world.

If there is more than one substance in the world, they must have, as we have noted, at least one basic relationship to one another, for they are parts of the same world. Since their combination causes the world to exist, that relationship together with the substances might be said to explain the world. But if having such a relationship did account for everything in the world, it would be trivial, for nothing that is contained in any one of the ontological causes is really explained. It is merely assumed.

Finally, if the substances in the world had no further relationship to one another, beyond being different parts of the same world, they could not combine to constitute anything, except for the world as a whole. Though each substance might be said to cause itself ontologically (because it would still constitute its own existence), that would explain nothing, for its existence is precisely what is assumed in postulating the substance. It too would be trivial.

Nature of relations

We must assume, therefore, that basic substances have relationships of some kind to one another (beyond simply being parts of the same world). That is not to assume that relationships are something that exist in addition to the substances that have them. We can and will assume that the basic relationships are simply how basic substances exist together as a world. For example, bits of matter may be assumed to have spatial relations to one another as how they exist together as a world; or bits of matter may be assumed to exist together with space as a substance by coinciding with some part of space or other; and parts of space may be assumed to exist together as a world by having unchanging geometrical relations to one another. Such basic relationship are like properties, which, as we have assumed, are simply aspects of substances. But instead of being aspects of substances taken separately, the relationships we are assuming are aspects of the world, or how substances exist together as a world.

The basic relationships among substances being postulated as part of the ontological causes to be used in explaining everything in the world should be distinguished from the two relations, already mentioned, which substances have to themselves or among their parts: the identity relation and temporal relations. We are considering the relationships that an ontology must postulate along with substances in order to explain things ontologically, whereas the identity relation and temporal relations are aspects of how each substance exists on its own and do not depend on how they exist together as a world.

Since naturalism is the belief that what exists is just what is in space and time, one kind of basic relationship that any naturalism will require among substances is spatial. It is hard to see how any substance could be in space and time without having spatial relations to other substances. By spatial relations, I mean the distances that can hold between substances in three independent dimensions, and I assume that such distances are continuously variable.

Though spatial relations are found in the natural world, that does not mean that a naturalistic ontology must assume that having spatial relations is how substances exist together as a world. There is another way of existing together that would entail their having spatial relations: if space is a substance, bits of matter could have spatial relations by coinciding with parts of space. The real nature of spatial relations is another issue that we will leave open for the time being, until we are in a better position to decide what to believe. (See Space under Spatiomaterialism.)

Kinds of relations

As in the case of substances, there is an important difference to be recognized between kinds of basic relations that might be assumed to hold among the substances postulated. Though such basic relationships are just how the basic substances exist together as a world, they can, like the essential aspects of substances, be either temporally simple or temporally complex.

Temporally simple. Relations that exhibit their full nature at the moment that the substances exist together in that way are temporally simple. That is, relations are "temporally simple" to the extent that they are how substances exist together at a single moment in the history of the world. In a world constituted by space and matter, for example, the basic relationship between the two basic substances would be simple in this sense, for it would be true at every moment that each bit of matter coincides with some part of space or another.

Temporally complex. The relations that exist fully at any one moment may, however, change the next moment. That is, some relations may go out of existence over time and other relations come into existence. Such relations would be contingent, and the only way to define the basic relations by which substances exist together as a world may be the way in which contingent relations change over time. If change in contingent relations were regular, the way that substances exist together as a world might be defined by how their contingent relations change, for that would be a relationship that does not change over time. That is, the relations among substances might be dispositional. To the extent that the relationship by which substances exist together as a world have a nature that is defined by how contingent relations change over time, it will be said to be a "temporally complex relation."

For example, an ontology may assume that the way that substances exist together as a world is by having spatial relations. Particular spatial relations change over time, for example, as objects move, and the possibility of such change could be built into the the meaning of "having spatial relations." "Having spatial relations" might accordingly be defined as meaning that substances have spatial relations of some kind or other at each moment, but that they can change from one moment to the next as long as they are all geometrically consistent as a whole. "Having spatial relations" would then be a temporally complex relation among substances, and the substances themselves could have a relatively simple, inert nature.

It is possible to hold that spatial relations are temporally simple without postulating space as a substance. The change in spatial relations could be explained by the temporally complex essential natures of the substances, such as material substances defined as substances that move and interact according to the basic laws of physics. That is, everything that happens in the world, including all the spatial relations that come to exist, might be explained as what is required because material objects obey the laws of physics. What must be assumed is that those material objects had certain spatial relations at the beginning, say at the Big Bang or when God created the world. The spatial relations assumed by such an ontology could be temporally simple, for they could all exist fully at a single moment, at the very beginning. (It might be mentioned, however, that this view would not even be possible, given the Heisenberg uncertainty principle of quantum mechanics, unless there is a so-called hidden variable that makes the indeterminism of quantum theory a mere appearance of the incompleteness of its explanation.)

Ontological effects

Ontological explanations use substances as causes to explain things in the world as their effects. Such causes produce their effects by constituting the things being explained. Since there are relations among substances, different effects can be produced when basic substances are combined in different ways.

It should be emphasized, however, that insofar as the phenomenon being explained is the same as the substance that constitutes it, the explanation is trivial and, thus, not a genuine explanation at all. The explanatory power of ontology comes from showing how the substances cited as ontological causes work together so that jointly they constitute what is being explained. Thus, even if the existence of some object is explained by showing how it is constituted by the combination of various particular substances, the object's properties are still not explained if they are simply the essential properties of the basic substances constituting it. For example, it does not explain why something is moving in a certain direction to say that all its parts are moving that way. The "explanation" in ontological explanations comes from showing how ontological causes work together to produce something that may seem different from them. Anything that is entailed by the essential natures of substances taken separately is not explained, but just assumed.

What is explained by ontological causes includes both the objects found in space and how they change over time.

Objects

The existence of particular objects can be explained by the substances constituting them. Substances have, as substances, an existential aspect to their nature, that is, they are self-subsistent, and the relations by which they exist together as a world permit them to work together in constituting objects. How they do so depends on the specific ontology.

Likewise the natures of objects found in the world, or their properties, can be explained by the substances constituting them because of the essential aspects of their natures as substances, that is, their essential properties, and the relations by which they exist together as a world permit substances to be combined in different ways.

Thus, it is possible to explain a diversity of things in the world. Things may be different in kind because they are constituted by different kinds of basic substances combined in the same way, or because they are constituted of the same kinds of basic substances combined in different ways, or because of some combination of both factors.

If only out of respect for the Pre-Socratic philosophers, it should be noted that the attempt to explain the world ontologically was first attempted about 600 BC, before epistemological philosophy began. These first philosophers were naturalists looking for the "first principle" (or arche) by which to explain the natural world, and they assumed that it must be a "stuff" of some kind that constitutes the existence of everything in the world. Thales thought it was water. His student, Anaximander, insisted it was an inchoate stuff ("apeiron") without properties of its own. And Anaximander's student, Anaximines, argued for it being air. Though these so-called "Ionian" Pre-Socratics disagreed about its essential nature, they all agreed that the world is constituted by only one basic kind of material substance. Their ontologies were forms of monistic materialism. Spatial relations were taken for granted.

As the Pre-Socratics soon discovered, however, none of these ontologies offered an adequate explanation of the natural world, for they could explain neither the diversity of the objects in nature nor the change that occurs in them. The only properties postulated by any of them were those that characterize the essential nature of the single kind of material substance making up the world, and that left unexplained all the properties that distinguish one kind of object from other kinds, not to mention how such properties could come or go from existence as time passes.

Parmenides can be read as making this point. What Parmenides was referring to by his famous dictum. "What is, must be, and what is not, must not be," was a basic aspect of the nature of substance (the temporal aspect of its existential aspect). Substance cannot go out of existence, nor can it come into existence. But since Parmenides agreed that the "first principle" for explaining the world is a single kind of substance (with a temporally simple essential nature), he argued that there cannot be any real change or diversity in the world. Thus, he insisted that change and diversity are an illusion.

Heraclitus drew the opposite conclusion from the assumption that there is only one first principle for explaining the natural world. But he took, as the first principle, change and diversity itself. That was, in effect, to deny that there is any such thing as substance underlying change or diversity. Since the essential natures of substances are defined by their properties, to take the change of properties as basic was to deny that properties are aspects of substances, for otherwise substances would have to be coming into and going out of existence as time passes. Though Heraclitus did assume that change and diversity are guided in a regular way by Logos (which is something like laws of nature), this is to read Heraclitus' famous claim that you cannot step in the same river twice as saying that what exists in the natural world is nothing but properties that change over time.

Between them, therefore, Heraclitus and Parmenides posed a dilemma for any explanatory ontology that would postulate only one basic principle to explain the world: either the first principle is a material substance of some kind and there is no change nor diversity, or else change and diversity themselves are the first principle, and there is no substance. The former fails to explain the natural world, and the latter abandons ontological explanation altogether.

Pre-Socratic philosophy was a process of posing hypotheses, criticizing them, and posing new hypotheses, and it discovered two ways of solving this dilemma.

Pluralists held that the world is constituted by more than one kind of material substance. That made it possible to explain diversity and change by the mixture and separation of different kinds of material substances each with a simple essential nature.

Empedocles postulated four basic substances, earth, air, fire, and water, and he explained the diversity and change of things in the world by their mixture and separation (according to the forces of "love" and "strife"). Anaxagoras gave the same kind of explanation, except that he postulated infinitely many different basic substances (or "seeds," as he called them). In both cases, the essential natures of the basic substances were defined in terms of their qualitative properties, such as hot and cold, wet and dry, and their mixture was supposed to account for all the other sensible qualities of objects. (It was probably the limited range of objects that could be explained by only four basic substances that led Anaxagoras to insist on infinitely many "seeds.")

The other solution to this dilemma was offered by the atomists, Leucippus and Democritus. They are said to have explained diversity and change "quantitatively", rather than "qualitatively," because they took spatial relations into account. They assumed that the material substances are atoms whose natures differ from one another only by their size and shape, and they explained the differences in kinds of objects not only by the shapes and sizes of their constituent atoms, but also by the spatial relations that hold among them. That forced the ancient atomists to believe, however, that the sensible qualities that objects seem to have are actually subjective, a view that was not generally accepted until the beginning of the modern era.

Change

In order to explain change, an ontology must not only assume that substances have a temporal aspect to their existential nature, but also that they can be combined in different ways at different times. In that case, as time passes, an object may change because some of the kinds of basic substances constituting it are exchanged, or because the relations by which the same basic substances are related in constituting it change, or because of some combination of such factors. But that is to assume that, in addition to having relations, the relations among basic substances are capable of change over time.

This is clearly what Empedocles was assuming in holding that the objects perceived in nature change because of the mixture and separation of elements, such as earth, air, fire and water. He took it for granted that they can move, explaining one kind of change by assuming the possibility of another, namely, motion.

The atomists, however, believed that it was necessary to explain how motion itself is possible. That is why they postulated the void as well as all the atoms. They are traditionally understood as having argued that bits of matter would not be able to move, if there were no void, because there would always be other bits of matter in the way. But if there were a void as well as the atoms, atoms would be able to move without obstruction, at least, until they collided with other atoms. However, since the void exists only where atoms do not exist, the void can be understood as a very subtle kind of material substances that atoms can displace more easily than other atoms. On that interpretation, atoms move through the void like fish through water, displacing a fluid-like substance which offers no resistance. We will return to their explanation of the possibility of change.

There is, it should be emphasized, no ontological explanation of change, if the change being explained is the same kind of change that the substances undergoing that change are postulated as having as part of their essential nature. Whether we are explaining objects and their properties or change in them, when cause and effect are the same, there is no ontological explanation, but only ontological assumption.

Explanatory ontology is, in sum, the attempt to reduce everything in the world to the various kinds of basic substances constituting them and the relations by which those substances exist together as a world. But that is explanatory only to the extent that the substances and their relations are more elementary than what they explain and produce those effects by how they are combined. But if it were successful, an ontological explanation of the world would be a simple and complete explanation of the world, for it would show how everything in the world is identical to certain basic kinds of substances and certain basic kinds of relations among them. Everything in the world would be explained in the same way.

Ontology as realism

For traditional, epistemological philosophy, ontology is realism (or, more precisely, its ontology is determined by the position it takes on realism). The foundation of epistemological philosophy is a theory about how we know (or a theory about the nature of reason) which is based on reflecting on our mental processes. From this foundation, it attempts to justify certain conclusions about the world, which would be necessary relative to our ordinary ways of knowing about it. Thus, success generally means that it is committed to the existence of certain entities beyond those assumed at the beginning. "Realism" is the name for belief in their reality. But realism is usually a form of dualism. Epistemologists are already committed to the existence of the subject whose way of knowing is the foundation for their epistemological argument, and realism commits them to the existence of entities of a fundamentally different kind. Hence, they wind up defending some form of ontological dualism, and that typically leads to anti-realism, since the two kinds of substances do not fit together intelligibly as a world. This pattern can be found in every era of the history of Western philosophy. I will suggest how, very briefly, in order to make clear what I mean.

Ancient

Reflecting on the difference between the objects of perception and the objects that seem to be present to us in reasoning about kinds of things, Plato argued that, in addition to all the visible objects in the realm of Becoming, there is a realm of Being where such objects of rational intuition exist as unchanging Forms. He called the latter realm "Being" because the Forms were supposed to be permanent and unchanging. It was supposed to be outside space and time, beyond the natural world of changing, visible objects. Thus, his realism committed him to believing in the existence of both Being and Becoming, and since they are so fundamentally different in their natures, his ontology is clearly a kind of dualism.

Plato’s was a very problematic dualism, because it is hard to explain how entities that are not supposed to be in space and time are related to visible objects which are, much less to show how such Forms could cause visible objects to have the natures they seem to have. That makes it easy to be skeptical about the transcendent realm of Being, and naturalists are already inclined to be anti-realists about abstract entities of any kind, because they assume that everything is located in space.

Aristotle tried to avoid these problems by postulating, instead, substances in the natural world that are compounds of two elements, matter and form. This was not, however, to abandon Plato’s epistemological foundation, for Aristotle continued to assume that the "material cause" is an object of perception and that the "formal cause" is an object of rational intuition. Though essential forms were located in space, they had to have a peculiar nature to play their role, because each had to be located in many different particular substances at the same time and yet be one and the same thing. That earned them the name "universals." Though Aristotle could claim to be a naturalist, he was still a realist about essential forms as something beyond what is known by perception. That landed him with his own ontological dualism because, even though neither matter nor form can exist without the other, the existence of one is distinct from and cannot be reduced to the existence of the other. Realism about universals invited a type of skepticism called "nominalism."

Attempts to avoid matter-from dualism characterize Aristotle’s later work on the nature of substance as substance. Though there is much dispute about it, Aristotle seems to argue in Metaphysics, Books VII and VIII, that substances are basically just essential forms. He apparently reduces the material cause to the fact that forms exist only as particular substances despite being entities that exist as many different particular instances of the same form (that is, as universals). That position seems to reduce matter to a principle of individuation. This later notion of essential form and matter is closer to the distinction between essence and existence assumed here (see Substances above). In any case, Aristotle's conception of being as being (that is, substance as substance) poses so many problems that many traditional philosophers have been inclined to avoid ontology altogether.

Medieval

In the Medieval period, realism took the form of belief in the existence of God, rather than a realm of Being, outside space and time. Theists believed that it was possible to prove the existence of God on the basis of what can be observed in the natural world. For example, they argued from the natural belief that every event has a cause to the existence of God as the first cause, or cause of nature as a whole. And they argued from natural teleology to God, both as the designer of the natural order and as the ultimate final cause of natural things. Realism about God, or theism, committed them, therefore, to believing in the existence of God as well as nature. After Augustine, this ontological dualism was modeled on Plato’s, and it was no less problematic. The fundamental difference in their natures makes it difficult to explain how God and the natural world are related as parts of a single world. It was ultimately left as a mystery that could not be fathomed by finite rational minds. Denial of this kind of realism is generally considered atheism, though mere skepticism about it is often distinguished as agnosticism.

Modern

With the rise of modern science, it was recognized that our perceptual experience of the natural world is something distinct from the natural world itself (as the ancient atomists first held), and the foundation of epistemological philosophy shifted from reflection on how we know in which we are living bodies in the natural world to reflection on how we know in which we are minds where ideas have an appearance. Mind is the epistemological foundation from which Descartes tried to prove the existence of the body and the external world of which it is part. The success of Cartesian philosophy would entail realism about the natural world, and thus ontological dualism. But mind and body are substances with such radically different natures that it is, once again, a very problematic ontology, namely, mind-body dualism.

There were, of course, skeptics about its success, notably, the British Empiricists, and they are interesting for their views about substance. Locke argued that realism about material objects involves belief in a substratum, or substance as nothing but a support of the properties that perception reveals objects to have. Since that was to believe that substances have no properties of their own, it was, in effect, to reduce substance as substance to its existential aspect, and thus, Locke could plausibly hold that substratum is an incoherent idea. But even the existential aspect was denied by Berkeley and Hume. They accepted the "bundle theory" of substances, that is, the view that substances are just the bundle of properties that we seem to perceive in them. In any case, since the foundation of modern philosophy was mind, they were implicitly committed to one kind of substance, and the only ontological position open to skeptics was idealism of some kind or other, though only Berkeley embraced it explicitly.

Later attempts to justify science from the epistemological foundation of modern philosophy led to other forms of realism, though they were not called that. Kant tired to avoid the problems of Cartesian philosophy by holding that space and time are merely forms of intuition in the mind. But since he continued to believed that there are things in themselves, he was implicitly committed to entities that are not in space and time. That landed him with the same kind of problematic ontological dualism as Plato, and like Augustine, he simply denied that it is possible to explain the relationship between the natural world and the things in themselves which are outside time and space.

Contemporary

Early in the twentieth century, developments in logic by Russell and Frege offered a new foundation for epistemological philosophy. Reflecting on our use of language, so-called Anglo-American analytic philosophy took as their epistemological foundation what we all know about the meanings and references of the terms and sentences we use. This foundation has been used in various way, leading to different forms of realism.

Analytic philosophy was able to reformulate empiricism as a justification of science at the expense of modern metaphysics. Logical positivists took the observation of objects in the natural world as the epistemological foundation of science, and they tried to show how scientific conclusions were supported by it. Though their original purpose was to show that whatever is not based on observation is meaningless metaphysics, it was soon noticed that even theories in physics mention unobservable entities, such as electrons, quarks, and force fields. Thus, those who believed in their existence came to called "realists about theoretical entities."

More recently, the recognition that such unobservable entities are not very different from the observable objects on which science bases its theories has led to calling the defenders of science "scientific realists." Scientific realism is taken to involve a commitment to the existence of both the observable and unobservable objects recognized by science. Or in the words of Wilfred Sellars, "science is the measure of all things, of what is that it is, and of what is not that it is not" (p. 173). But disputes still rage in the professional literature about the significance of calling it "realism."

Most recently, philosophers of science have tried to avoid problems about realism by simply abandoning traditional epistemology all together. They often call themselves "naturalized epistemologists," for they hold that the only foundation for justifying science is science itself (that is, the conclusions that science draws about how we know). Though they say that they believe that philosophy is continuous with science, to ontological philosophy, they seem to be giving up philosophy altogether in favor of being cheerleaders for science. See Kitcher and Rosenberg.

Giving up epistemological philosophy does not necessarily mean, however, taking up ontological philosophy. The habit of epistemology makes it seem that ontology is purely descriptive. The job of ontology seems to be just to discover the kinds of entities to which one is committed by holding certain beliefs to be true.

With regard to natural science, for example, ontology is just realism about the conclusions of science.

In the philosophy of mathematics, realism is defended by so-called Platonists, who hold that numbers and other mathematical entities exist independently of the subjects who know about them (in opposition to logicists, who argue that mathematics can be reduced to logical truth, and to constructivists, who argue that mathematical objects are simply constructs of the imagination).

Even language is taken as a foundation for descriptive ontology. Quine (1953,1960) has argued that talk of classes implies the existence of atleast that one kind of abstract entity. Some analytic philosophers now argue that to believe in the truth of descriptive statements is to be committed to the existence of properties as well as the substances that have them, or what might be called substance-property dualism.

Scientific realism leads some analytic philosophers of science to take laws of nature to be real, which entails a dualism of laws and the objects that that obey them.

In any case, realism is not explanatory ontology, but just ontology as realism. It does not use the entities it postulates to explain anything beyond the phenomena on which their existence was defended. That leaves plenty of room for philosophical argument, because descriptive ontologists generally take a skeptical attitude and are inclined to deny the existence of any kinds of entities whose existence is not forced on them by their epistemological foundation. But that is a different issue entirely from explanatory ontology.

Method

The final assumption needed to secure a foundation for ontological philosophy is a method for deciding which of the possible ontological explanations to believe. We will assume that we ought to believe the best ontological explanation of the world, and since we are naturalists, that means preferring the best ontological explanation of the natural world. Since the empirical method can be defined as inferring to the best explanation, that makes the foundation of ontological philosophy empirical ontological naturalism.

The empirical method is the same method that science uses, except for applying it to a different kind of explanation. But it is not the only possible method for deciding what to believe. The alternative is the rational method of traditional, epistemological philosophy. Its foundation was a theory about how we know, which was based on reflecting on our processes of knowing. It might also be considered an inference to the best explanation. But since the way we ordinarily explain what is known by reflection is by giving reasons, the method of epistemological philosophy always came down to the claim that certain truths are required by reason itself. Though the actual standard was different in different eras of Western philosophy, they can all be called forms of the rational method.

The empirical method, by contrast, may be considered an inference to the best explanation of what is known by perception. Perception provides relevant evidence in deciding what to believe because it discloses facts about what exists in the world. But for naturalists seeking an ontological explanation, there is no need to limit the evidence to perception.

Given our assumption, as naturalists, that the natural world is the world disclosed to us by perception, the empirical method might also be described as inferring to the best explanation of the natural world. Though science may limit itself to explaining what is known by perception, the latter formulation is preferable, given our ontological purposes, because there is no need to limit the evidence we have about the natural world to what is known by perception. Reflection should also be accepted as providing evidence about the nature of the substances and relations constituting the natural world, because we believe, as naturalists, that the beings in whom reflection occurs are themselves parts of the natural world. That would not be to revert to the rational method of epistemological philosophy, as long as we take reflection and what is known by it to be something found in the natural world that needs explaining, and not as providing a standard for judging what is true. What is known by reflection is no less evidence of what exists in the natural world than what is known by perception, though when we define "naturalism" ontologically, as holding that the world is just what is in space and time, we are taking perception to disclose its basic nature more completely. Thus, since it is the natural world itself, not just what is perceived, that we are trying to explain ontologically, we shall interpret the empirical method broadly as inferring to the best explanation of the natural world, not just what is known by perception.

Having assumed naturalism and the validity of ontological explanation, the third and final assumption of ontological philosophy is the empirical method. That is, if this argument is logically valid, it will not be possible to reject the necessary truths justified by it, unless one denies naturalism, the validity of ontological explanation, or the empirical method.i

The empirical method

By the "empirical method," I mean an inference to the best explanation of what is found in the natural world (either by perception or perception and reflection). Though this way of deciding what to believe presupposes a kind of explanation, the method can be stated abstractly, because its standard for judging what is best that can be applied to any kind of explanation, or at least, any kind that cites causes in order to explain effects. So let us consider the method abstractly, and then take up the various applications of it.

Inference to the best explanation of the natural world

The standard for the best explanation is simply explaining the most with the least. The best explanation can be identified as the one that requires the least in the way of causes to explain the most in the way of effects. After explaining what this empirical standard requires generally, we will see how it applies to various kinds of explanation, including ontological explanation.

Scope

The explanation with the greater scope is better, other things being equal. That is, if two explanations are equally simple, the empirical method requires us to prefer one over the other, if it explains more of what is found in the world than the other.

The preference for explanations with larger scopes does not always determine which explanation to believe even when other things are equal. When two theories have overlapping scopes, for example, it may be unclear which explains more.

Simplicity

The simpler explanation is better, other things being equal. What does the explaining in an explanation are its causes, for they produce the effects, which are what is explained by the explanation. Thus, if two explanations explain the same range of phenomena, the empirical method requires us to believe one rather than the other, if it requires fewer causes or the causes it requires are simpler.

Nor does the preference for simpler explanations always determine which theory to believe when other things are equal. There may be a trade-off between fewer causes and simpler causes. There is no way to say in general whether to prefer fewer, more complex causes or a larger number of simpler causes. It depends on the kind of explanation involved or, perhaps, the specific case. And even then, there may be no way to decide.

Scope and simplicity are the basic criteria for judging explanations, but there is no reason to deny that there may be other issues about which is the best explanation that arise when specific kinds of explanations are being considered. Appeal can always be made to the basic standard for judging the best among explanations of the same basic kind: explaining the most with the least.

Two sources of error using the empirical method should be noticed.

First, any limitation in the range of theories being considered can lead to errors. Since the empirical method chooses the best among the possible explanations, it works only insofar as all possible theories are being considered.

Second, any limitation in the range of evidence being considered can lead to errors. Since the empirical method chooses the best explanation of what is in the world, it works only insofar as we have found everything relevant in the world. And as mentioned above, naturalists have no reason, in principle, not to include as evidence, along with perception, what is found out about the natural world by reflection, if it is relevant. The subjects and the mental processes on which they reflect are part of the natural world.

Kinds of inferences to the best explanation of the natural world

Since the empirical method is relative to the kind of explanation being sought, we must have the ability to comprehend some kind of explanation in order to use it. Nor can we say in advance which kind of explanation ought be used. We must simply develop whatever ways of explaining we can understand, and then compare them to see how they fit together or, if we must choose among them, which to believe.

Efficient-cause explanations

The empirical method of science is to infer to the best efficient-cause explanation. Explanation by efficient causes is understood as depending on laws of nature, which describe regularities about how causes lead to effects. It is usually represented by the deductive-nomological model (or covering law model, which can be traced to David Hume). This model holds that an event (or regularity) is explained when a description of it can be deduced from true laws of nature and the relevant initial and boundary conditions.

The initial and boundary conditions, or certain salient parts of them, are said to be the cause, and the event (or regularity) entailed by them and the law of nature is the effect.

This model works well for physics, but there has been a long dispute about its adequacy for other branches of science. Those disputes are not relevant here, since we are more concerned with comparing efficient-cause explanations with other forms of explanation than with details about how it is applied in specific cases. (A better account of the kinds of scientific explanations that this model slights will be given when we take up the necessary truths of ontological philosophy. See Change: Epistemological theories of causation)

Scope

The explanation of any specific event (or regularity) is just one of a whole range of explanations that may be based on the same law, and the scope of the explanation includes all the events (and regularities) that can be explained by it. According to the empirical method, therefore, the best efficient-cause explanation, other things being equal, is the one that follows from the most general laws of nature, that is, the natural laws with the largest scope.

Simplicity

The simplicity criterion requires us to prefer the explanation with the fewest causes and the simplest causes, other things being equal.

The explanation with the fewest causes, in the case of efficient-cause explanations, would be the one with the fewest relevant initial and boundary conditions. Since what makes such conditions relevant are the laws of nature, this is usually the requirement of preferring efficient-cause explanations that require the fewest laws. Thus, given any two explanations with the same scope, the empirical method requires us to prefer the one requiring the fewest laws of nature and the fewest relevant initial and boundary conditions. But if two explanations appeal to the same laws, we should prefer the one that requires the fewest and simplest initial and boundary conditions.

The explanation with the simplest causes may also mean, in the case of efficient-cause explanations, the one with the simplest laws of nature. The criterion of simplicity in this case has notorious problems, because natural laws formulated in terms of quantitatively precise mathematical formulas can be simple in different ways. However, even without a generally accepted standard of mathematical simplicity, scientists usually manage to reach agreement on this matter. Those issues need not, in any case, concern us, given the altitude of our comparison of these forms of the empirical method.

Since criteria for explaining the most with the least can be traded off against one another, the empirical method does not necessarily determine which theory to believe in science. But this is how the goal of science is usually formulated. The so-called "holy grail" of contemporary physics is an example. That goal is to find a single, basic natural law that would cover all the forms of motion and interaction among bits of matter that physics recognizes, including not only electromagnetism and the weak and strong (or color) forces, but also gravitation. This goal shows a commitment to finding the simplest explanation with the largest scope, though physicists have encountered intractable problems in their quest to formulate such a law. (The biggest problem is that it does not seem possible to state Einstein's theory of gravitation in the same kind of mathematical formulation as the laws for the other basic forces, that is, as a quantum field theory, without postulating ten or more dimensions of space!)

Efficient-cause explanations are also given in ordinary life, engineering, and less basic branches of science, where the empirical method is applied more loosely. We can understand most causal connections apart from formal deductions for mathematically formulated laws of nature, because we have a form of imagination (spatial imagination) that enables us to think about the relations of objects in space and to how they change as objects move and interact over time. Spatial imagination represents very basic regularities, which are implicit in the laws of physics, but it can also represent what specific laws of nature require against this background understanding. This remarkable capacity is easily overlooked, because it is built into our faculty of perception as our way of understanding what perception discloses about nature. In any case, this way of understanding efficient-cause explanations enables us to use the empirical method, because, despite its non-formal nature, it enables us to see which theory explains the most with the least.

When events that depart from expectations, such as accidents, for example, are explained by efficient causes, the empirical method enjoins us to prefer the explanation that requires the simplest causes (the simplest deviations from normal, which are most likely) and the fewest causes (rather than a combination of independent deviations). But it also requires us to prefer the explanation with the largest scope, and thus, we prefer an explanation that can also account for other details about the accident. Or in the case of regularities generated by a mechanism of some kind, the empirical method would have us prefer the simplest mechanism that can explain the most about the regularity in its behavior. Such judgments depend more on our capacity for spatial imagination than precise formulations of laws of nature, though the latter may be relevant in choosing among them when more precise quantities are relevant.

Rational-cause explanation

Though social science also uses the empirical method of natural science, it has another kind of explanation which it shares with the humanities, distinguishing it from natural science. It is called "rational explanation." Since it explains phenomena by causes, the empirical method can be used in inferring to the best rational explanation. But the nature of rational explanation is such that the empirical method does not, in general, lead to agreement about what to believe about the world. What follows is not meant to defend rational explanation in science, but merely to show how rational explanation can be seen as another instance of the empirical method.

It is possible to explain what rational beings like us do and believe by the reasons that lead them to choose to do it or to believe it. For example, actions can be explained by the beliefs and desires that are responsible for them, and beliefs can often be explained by the perceptions and established beliefs that are responsible for them. When we are explaining the actions or beliefs of other subjects, what is explained are ultimately objects of perception, just as in natural science, for we know about their intentions and beliefs of others only by perceiving their behavior. Some of that behavior is, of course, verbal behavior, which is especially revealing, but this kind of explanation can also be given of other animals, notably, mammals. What makes human beings basically different is that they are reflective subjects. That is, in them, beliefs, desires and perceptions are not mere causes of actions and belief, but causes that have effects on other beliefs or behavior by way of the subject’s reflecting on them. These causes are so special that they are called "reasons." Furthermore, what enables us to identify these causes and see their roles in causing action and belief is reflection.

Reflection plays a role in rational-cause explanation that is analogous to the role of spatial imagination in ordinary efficient-cause explanations and the laws of nature cited in more formal scientific efficient-cause explanations. What enables us to connect cause with effect in the case of rational explanations is reflection on our own capacity for reasoning. When we explain another person’s action by citing certain beliefs and desires, our ability to tell the relevance of those beliefs and desires as causes of the action in question comes from reflecting on what we would do if we had certain desires and we believed that we were in the relevant situation. Likewise in seeing the relevance of reasons as causes explaining certain beliefs, we reconstruct the argument in our own brains.

Rational explanation works well enough in the case of the actions and beliefs that occur in the ordinary practice of carrying out our lives. Insofar as the actions and beliefs to be explained have to do with moving bodies around in a world of objects in space in order to satisfy desires, we can understand the causes of the other’s behavior by reflecting on what our own spatial imagination would lead us to do in the situation. That is the kind of behavior that can be explained rationally in other animals. But we can usually reach agreement about ordinary social interactions of human beings as well, because members of a society share expectations about one another’s actions and beliefs. To explain a particular action or belief is usually just a matter of identifying which of the familiar reasons happened to be responsible for it in that case.

Agreement about which is the best rational explanation is reached easily in such ordinary causes, and it can be seen as an application of the empirical method. Familiar reasons are the simplest in the sense that they fit into the background of beliefs and desires that people share, and we usually prefer explanations that require the fewest familiar reasons to explain any particular action or belief. In short, we assimilate their behavior to what is normally expected. Furthermore, the scope of such explanations is maximally large, because the rational explanation is confirmed by how normal expectations also explain other aspects of the person’s behavior.

Actions or beliefs that are unusual, however, cannot be assimilated to the normal pattern. They call for rational explanation in a way that can also be seen as an application of the empirical method. We start, as always, from the neutral background of ordinary behavior and beliefs with generally accepted reasons in the society and we try to identify the special reasons that are responsible for the unusual beliefs or behavior. These are desires, beliefs or perceptions that stand out as different from that neutral background, and since the empirical method requires us to explain the most with the least, we look for the explanation that requires the fewest deviations from the background and the simplest (or most plausible) ways in which they might deviate. And we look for the combination of such deviations with the largest scope. The same beliefs and desires can cause many different actions and beliefs, and thus, we prefer the rational explanation of the action (or belief) in question that can also explain other actions (or beliefs). The more of a person’s behavior that a rational explanation can explain, the better the explanation, other things being equal.

Though each of us may use the empirical method to decide what to believe about the reasons for a person’s behavior or beliefs, this may not lead us to agree on which the explanation. The problem is that rational explanation depends on reflection, rather than just perception. Each of us must use our own processes of reasoning to judge which possible reasons explain the most with the least. Those reasoning processes involve our own beliefs about the world, the perceptions that we have had, our own desires, values and what we have already decided to do or believe on the basis of them. And the further what is being explained is from the familiar, everyday actions and beliefs that we have all made part of our way of viewing the world, the more differences tend to show up in how we think. People have vastly different views about the most general and basic issues, such as the nature of the world, what is possible, where beings like us come from, what is the purpose of life, what is good and bad, what to strive for, what is worth worshiping, and the like. And such differences extend into everyday actions and beliefs when those giving the explanations come from different cultures. Since what is the best rational explanation depends, in part, on which set of background beliefs and goals the explainers themselves accept, the empirical method does not, in general, make it possible to reach agreement.

It is widely recognized that the social sciences and humanities are not as objective as the natural sciences. But that is not an indication of any inherent weakness in the empirical method. It is, rather, an indication of the difference between the forms of understanding that are required for the explanations involved. Spatial imagination is more uniform than rational imagination, and that makes it easier for people to agree about which theory explains more with less. What the relativism of the social sciences and humanities shows is not the weakness of the empirical method, but the weakness of rational explanation (at least, as long as we come from different cultures and have different basic beliefs and values).

Ontological-cause explanations

The empirical method can also be used in philosophy (and science) by inferring to the best ontological-cause explanation of the world. The nature of ontological explanation has already been explained: it explains the existence of everything found in the world by showing how it is constituted by basic substances and the basic relationship by which they exist together as a world.

This kind of explanation is intelligible to us because of our spatial imagination (that is, the capacity to think coherently about spatial relation and how they change as a result of motion). That is the same capacity on which efficient-cause explanation depends. The difference is that what is being explained by ontological explanations includes the existence and basic traits of the objects found in the world, such the fact that objects have spatial relations and that change is possible, not just what happens to them. But an adequate ontology must also be able to explain why (true) efficient-cause explanations are true. The relationship between an efficient cause and its effect is a kind of regular change, and an ontology must show how the regularities described by the basic laws of physics can be just aspects of basic substances enduring through time with the basic relationship that makes them parts of the same world. That is how ontological-cause explanations are more basic than efficient-cause explanations -- they explain the premises of efficient-cause explanations, both the laws of nature and the initial and/or boundary conditions.

Ontological explanations differ from one another in the kinds of basic substances they postulate and what they assume about how substance exist together as a world, and empirical ontology decides which is true by which offers the best ontological explanation of the world, that is, which explains the most with the least.

Scope

It might seem that ontological theories are all alike in scope, because they all claim to explain the possibility of everything found in the world. The failure to account for any aspect might be said to show that it is not an ontological explanation at all, must less an adequate one. This is not quite true, however, for two reasons.

First, because there is a difference between explaining and merely assuming. The causes by which an ontology explains the world are the substances it postulates and the basic relationship it takes them to have, and thus, to the extent that what is being explained about the world is the same as what is assumed by the ontology, it is not really explained, but merely assumed. To some extent, that may be true of every possible ontology, but the best one will be, other things being equal, the one in which more is explained and less is merely assumed. That one has the greater scope.

The second reason is that, in an ontological explanation, there is a difference between explaining the possibilities of aspects of the world and explaining their necessity, and the more aspects of the world that are shown to be necessary, the better the ontological explanation.

What an ontology entails about the world holds necessarily. Though that determines the range of what is possible, contingent aspects of the world are left to be known though experience of what is actual. An ontology does not itself explain why certain contingent conditions are actual and others not; that requires an efficient-cause explanations. However, since it must explain the possibility of what is contingent, it may be said to "account for" whatever falls within the range of the possible.

Thus, the minimum requirement of an ontological explanation is that it, at least, "accounts for" everything in the world (in the sense of showing that it is possible). And if anything is found in the world that could not exist, if the ontology were true, then the ontology must be false. But ontologies that are not falsified may differ in the range of what they show to be necessary and what they imply is merely contingent. The principle of explaining the most by the least would require those committed to the empirical method to prefer ontological explanations in which more about the world is shown to be necessary and less turns out to be merely contingent. Thus, there is another possible difference in scope among ontological theories

Simplicity

The simplicity criterion requires us to prefer the explanation with the simplest and fewest causes, other things being equal. In the case of ontological causes, the explanation with the simplest and fewest causes would be the one that postulates the simplest and fewest kinds of basic substances and simplest basic relationship among them. Thus, given two ontological explanations with the same scope, the empirical method requires us to prefer the one that postulates the simpler basic substances, the fewer kinds of basic substances, and the simpler basic relationship among them.

Though it is generally clear which theory has the fewer basic substances, it may not be clear which kinds of basic substances and which basic relationships are simpler. From what we have assumed about the essential natures of basic substances and relationships, however, there is one clear criterion. We have seen that the essential natures of substances may be temporally simple or temporally complex, depending on whether their essential properties exist fully at each moment or they are dispositional and have to do with regularities about how contingent properties change over time. And we have seen that there are also such differences in the simplicity of the basic relationship by which an ontology describes how they are parts of the same world. Thus, given two ontological explanations with the same scope and same number of kinds of basic substances, the empirical method requires us to prefer the ontological explanation whose substances have the simplest essential natures and the simplest basic relationship to one another.

When all these criteria weigh in for the same alternative, the empirical method is decisive. But trade-offs among them can keep the empirical method from telling us which ontological theory to believe. That does not necessarily mean, however, that limitations in the mechanical application of these criteria can be used to argue that no choice can be made among theories in which there are trade-offs. It may still be obvious, when specific trade-offs are considered, which one explains the most with the least.

The rational method

For epistemological philosophy, by contrast, the method of choosing what to believe is not the empirical method, but the rational method. This is not quite the same as an inference to the best rational-causal explanation, because what epistemological philosophy needs in order to be a kind of philosophy is a foundation from which to prove necessary truths about the world. What makes epistemological philosophy different from ontological philosophy is that it uses as its foundation a theory about the nature of reason rather than a theory about the nature of the substances constituting the world. And the necessity of its implications comes down to their certainty, given the certainty of the epistemological foundation. Its reliance on a theory about how we know about the world is what earns it the name "epistemological" philosophy (epistemology being, literally, the explanation of knowing). Moreover, such a foundation is secured by reflecting on how we know. As we have seen, reflection is what enables us to give rational-case explanations of the beliefs and behavior of other beings like use. But epistemological philosophy uses reflection to explain how reason works in general. That is, it uses reason's own power to reflect on how it works to defend a theory about how reason works, rather than merely to say which reasons are responsible for particular conclusions about what to believe or do.

Its theory of how we know is supposed to show that certain truths must hold of the world, and its success in using its foundation to prove necessary truths about the world is called realism. Since it would show that something exists beyond its epistemological foundation, it typically leads to metaphysical dualism of one kind or another (as we have seen in Ontology: As realism).

The theories about the nature of reason used by epistemological philosophy are all based in one way of another on a faculty of intuition, which is taken for granted. (The reason for this reliance on intuition is explained in Change: Evolutionary stage 10: The career of epistemological philosophy.)

There is, however, so little agreement in the history of philosophy about the nature of reason that the best way to explain the rational method of epistemological philosophy is to survey the main kinds of theories about the nature of reason that have developed in the history of philosophy.

Ancient Philosophy

Plato assumed that we know by a kind of intuition in which the objects of knowledge are present to the subject. In the case of perception, they are visible objects in space which can move and interact with other objects, and these he assumed were parts of what he called the "realm of Becoming." We also have a capacity to reason about things, in which we understand their natures, and the objects that are present to us in this way of knowing are what Plato called the Forms, which he believed exist in a realm of Being outside space and time. His "doctrine of recollection" is a myth that explained this rational intuition as resulting from our immortal souls having existed in the presence of the Forms prior to our acquiring bodies in the realm of visible objects. Since the objects of rational intuition are the natures that we recognize in visible objects, he thought that the Forms were responsible for visible objects having whatever natures they seemed to have. Thus, by intuiting the Forms directly, we could know truths about them that are necessary relative to perception, that is, our ordinary way of knowing. That included knowing what is good about visible objects, since the Forms were supposed to follow from The Good Itself and visible objects were supposed to be striving to be like their Forms.

Aristotle also understood perception and reason as forms of intuition that make their objects present to us, though he explained them differently. Perception was supposed to be the result of our sensitive soul taking on the same kinds of sensible forms that exist in the particular substances, and reason was supposed to be the result of our rational souls taking on the essential forms of the objects as a result of "induction" from our perceptual experience of many instances of their kinds. Knowing the essential form of an object gives us knowledge of what holds necessarily, because according to Aristotle, there are final causes at work in nature that make natural substances change in the direction of an end state which is the fullest actualization of their essential form. Not only does that explain certain changes that they undergo, but it also tells us what is good for them. This knowledge, Aristotle argued, was prior to the received, ordinary ways of knowing the true and the good.

Medieval philosophy

Medieval philosophy is basically a continuation of Platonic dualism, except that The Good Itself, or a Form, is replaced by God, or a person. Thus, it retains the theory about the nature of reason on which ancient epistemological philosophy was based. If anything was new in the Medieval period, it was how the new view about the nature of the transcendent being was used to argue for its existence. And the main reason that these argument for the existence of God were not compelling in the end is that they are based on the assumption that principles recognized to be valid within the natural world can be applied to the natural world as a whole.

The belief that every event has an efficient cause can be used, for example, to show that there must be a first cause, when it is assumed that the world as a whole is an event to be explained. Final causation affords a similar proof of the existence of God. Given that every natural change within space and time has a final cause, it could be argued that there must be a final cause of the natural world as a whole, as long as it was assumed that the world as a whole is a kind of natural change and can be explained by the same principle. The argument from design works in the same way. Given that artifacts can change for the sake of an end that is good for them only because they are designed to do so by their creator, the fact that nature itself involves change for the sake of ends that are good could be used to show that there is a creator who designed the natural world to bring about such ends. Even the argument from the recognition of a difference between better and worse to the existence of something that is best can be used to show the existence of God when it is assumed that the world as a whole is not the best.

The ontological argument was the most original use of the rational method in the medieval period to prove the existence of God, and given our assumptions about the nature of existence, we can see the fallacy involved in it. As Anselm put it, since we can think of being "than which none greater can be conceived," God exists. For if the being we are thinking of did not exist, there would be a greater being, namely, one with all the same perfections we were thinking of plus existing. The premise of this argument is that absolute perfection entails existence. But if existence and essence are the two basic aspects of the nature of substance as substance, existence is not entailed by perfection, for perfection characterizes a things essential nature and that is a different aspect of any substance from its existential nature. The perfect being would exist only if he is a substance, and not just a conceivable essence.

This is not quite Kant’s critique of the ontological argument, for he argued that existence is not a property at all. On our theory about the nature of substance, existence is a property, albeit a very basic property — as basic as having an essence is. Having both properties is what makes something a substance.

Modern philosophy

Modern philosophers had a fundamentally different theory about how we know, for they had given up naïve realism about perception and recognized that the appearance of the natural world in perception is part of the subject, which they understood as ideas in an immaterial mind. That was also to give up the belief that reason is a direct intuition of Forms existing independently of the mind. But on reflection, they found certain ideas in the mind whose truth they could not doubt, and such so-called clear and distinct ideas were taken to be truths that hold necessarily. Descartes believed that clear and distinct ideas enabled him to prove (by way of proving the existence of God) that a natural world exists independently of the mind and is the cause of our perceptions. He also believed that this showed that the natural world has the essential nature of extension, and thus, he claimed that philosophy provided knowledge about the natural world that is necessary, relative to what is known by perception. Since rational knowledge is prior to what is known by experience, Descartes believed that he had justified the method of modern science as a way of learning the details of natural mechanisms. Other rationalists, such as Spinoza and Leibniz, argued from similar theories about the nature of reason to necessary truths about the natural world.

Kant defended necessary truths about the natural world on a theory about how we know that sees the mind as constituting in part what is known, including the natural world investigated by science. Thus, Kant could argue that the part of what is known that depends on the mind’s contribution is a priori knowledge about the natural world, holding universally and necessarily relative to what perception discloses about what is actual in the world, or what he called synthetic a priori.

Kant’s theory of knowledge forced him to deny that we could know the real nature of things in themselves, that is, what really exists independently of mind, but Hegel adapted Kant’s theory of knowledge in a way that enabled him to claim for philosophy the power to know the real nature of the world. He assumed that that the object of knowledge was entirely constituted by a mental substance through what he called dialectical reason, and thus, by reflecting on the nature of dialectical reason, Hegel also thought that it was possible to show what holds necessarily about the world, relative to what is known by science or other ordinary ways of knowing.

Contemporary philosophy

Even contemporary analytic philosophy had a rational method of knowing what is necessary about the world. They assumed that as users of language, we know the meanings and reference of the terms and sentences we use. Though we can use language to describe what we observe in the world and, thereby, follow the empirical method in science, they argued that there are certain truths that hold necessarily about the world because they are entailed by the meanings of the terms we use. Thus, analytic philosophy had a rational method for justifying necessary truths, though it was much less ambitious than earlier kinds of epistemology, because what is necessary was limited to analytic truths.

In each era, there have also been skeptics about the rational method, especially when they entailed kinds of ontological dualism, such as form and matter and mind and body, in which it was hard to explain how the two different kinds of substances could be related as parts of the same world. The inability to answer those skeptics led to doubts about the rational method itself and ultimately to the demise of epistemological philosophy.

Spatiomaterialism

Given these three assumptions of ontological philosophy, the final step in securing its foundation for necessary truths is to use them to decide what to believe about the basic nature of existence. As it turns out, the empirical method is decisive. There is one ontology that we must choose over the others, if we follow the empirical method, and it is different from the currently accepted ontologies. The two received views are both ontologies of science. They come from realism about contemporary physics. One is materialism, the view that matter is the only kind of substance constituting the world, whereas the other maintains that an opposite kind of basic substance helps matter constitute the world, namely, spacetime. But as we shall see, naturalists who take ontology to be explanatory and follow the empirical method in deciding what to believe ought to reject both in favor of the view that the world is constituted by space and matter, both existing as substances in time, or what I will call "spatiomaterialism."

We can see that spatiomaterialism is the best ontological explanation of the natural world by considering the various possible theories on each of the basic issues about what exists in the natural world: time, space, and matter. In each case we will decide what to believe by which theory offers the best ontological explanation of what is found in the natural world -- the one that explains the most with the least.

Our conclusion will be, however, that we ought to accept these ontological position if they are otherwise possible. There are ways they may be falsified by certain unobvious phenomena which we are not currently taking into account. I mean the observations used as evidence for Einsteinian relativity, as well as the fact of consciousness, the real difference between good and bad, and the validity of the belief that there is something worthy of worship. We will not be in a position to show how those phenomena can also be explained until we take up the necessary truths of ontological philosophy.

Time

We have already assumed that the world is in time by assuming that substance as substance has a temporal aspect to its nature, but as we have also seen, there is a further issue to be decided.

Possible explanations

We know from our experience of the world that objects are in time as well as in space, but as we saw in Ontology: Temporality, there are two possible theories about the nature of time. We are looking for an explanation of the world by substances, but we can believe either that substances endure or that they perdure over time.

Endurance theory of time

To hold that substances endure through time is to hold that they exist only at the present moment. Existence itself is in time. The past and the future do not exist. This view is sometimes called "presentism," but we are also assuming that what exists are substances. Thus, since substances never come into existence nor ever go out of existence as time passes, the substances that exist now did exist in the past and will exist in the future. In other words, substances are identical across time. Each substance that exists at one moment is identical to some substance that existed or will exist at every other moment in the history of the world.

Perdurance theory of time

To hold that substances perdure over time is to hold that all the moments of their histories exist in the same way. Time is just a relation that holds among those moments. The past and the future exist in the same sense as the present, for "past’ and "future" are just ways of referring to other moments relative to some moment taken as present. Though the perdurance theory of the temporal existential nature of substances can agree that substances never come into existence nor go out of existence over time, what they mean is that substances are wholes made up of parts, with each substance having a momentary part for each moment in the history of the world.

The best ontological explanation of time

Between these two theories, the empirical method requires us to prefer the one that explains more with less, that is, the one that uses fewer and simpler ontological causes to explain more phenomena as effects. According to each criterion, the endurance theory is clearly superior. Consider, first, simplicity.

Simplicity

The perdurance theory must postulate many more substances as ontological causes than the endurance theory, because it holds that every moment in the history of each permanent substance has a distinct and equal existence.

In fact, each moment is like a substance, according to the perdurance theory, for it is a distinct ontological cause that must be postulated separately in order to explain the world ontologically. But if such moments are substances, they are rather unusual substances, because they lack the temporal aspect of the existential aspect of the nature of substance as substance. (Though they are as eternal as the world, they do not exist at every moment in the history of the world, for they are only one moment in the history of a permanent substance.) Still, they have particularity. Each moment is a particular substance with an existence that is distinct from every other substance (including all the other moments in the history of the same permanent substance). Thus, each has both an existential and essential aspect to its nature (its essential nature being whatever properties hold of the permanent substance at the relevant moment in its history). So let us grant that they are substances of a kind. I will call them "momentary substances," since they do not endure through time but exist non-temporally (if not eternally) as one moment in the history of a permanent substance.

Since every momentary substance must be postulated separately, the perdurance theory requires many more ontological causes to explain each permanent substance postulated by the ontology. Indeed, the perdurance theory must postulate (indenumerably) infinitely many momentary substances for each permanent substance, since time is continuous (as evident in its infinite divisibility), and may well be eternal (that is, infinite in extent). Judging simplicity by the number of ontological causes required, therefore, the empirical method requires us to prefer the endurance theory. The endurance theory needs to postulate only one enduring substance to account for each permanent substance in the world.

It may seem, however, that there is a defense for the simplicity of the perdurance theory. Though its "momentary substances" are greater in number, each is simpler in its nature than enduring substances, and thus, its ontological causes are simpler.

What makes momentary substances seem simpler than enduring substances is that momentary substances do not have to endure through time, but can simply exist eternally as one moment in the history of a permanent substance. But why is that simpler?

Perhaps, the simplicity comes from having a temporally simpler nature. Momentary substances cannot have temporally complex properties, because they are what exists at only one moment in the history of a substance that never comes into existence nor goes out of existence. But that does necessarily make them simpler than enduring substances, for enduring substances can also have essential properties that exist completely at each moment of the existence of the substance. On both views, therefore, the essential properties of substances can exist completely at each moment of the existence of the substance. Thus, the only difference between them is that enduring substances exist at many more moments than momentary substances. But that is just the difference between them. To take that as showing the greater simplicity of the perdurance theory would be to beg the question.

On the other hand, perhaps the greater simplicity is supposed to come from its theory about the nature of existence. The endurance theory holds that existence itself is in time, and since that means time is an aspect of existence, a permanent substance must endure through time in order to exist as a substance. Thus, it might be argued that the perdurance theory is simpler, because it takes existence to be just the self-subsistence of the momentary substances making up the histories of permanent substances. Existence is non-temporal, rather than being in time. And this greater simplicity about the perdurance theory enables it to explain ontologically why permanent substances exist at every moment in the history of the world: each permanent substance is a whole made up of many momentary substances as its parts.

However, that supposed ontological explanation brings out the cost of not assuming that existence is in time. Not only must the perdurance theory postulate infinitely many momentary substances to account for each permanent substance, but it must also assume a basic relationship that gives those momentary substances infinitely many relations to one another. The events in the history of a permanent substance occur in a certain order, and so the momentary substances that must be related in a certain way in order to constitute it. Though those relations may be simply how the momentary substances exist together as a world, they must all be assumed in order to deny presentism.

Thus, not only are momentary substances not simpler than enduring substances in virtue of having temporally simple essential natures, but the perdurance theory must also postulate infinitely many momentary substances with infinitely many relations among them to account for each permanent substances.

As far as simplicity is concerned, therefore, endurance theory is clearly superior. It postulates one enduring substance to account for each permanent substance, whereas the perdurance theory must postulate infinitely many momentary substances with infinitely many relations among them in order to explain each permanent substance. But this ontological extravagance might be justified, if the perdurance theory can explain why permanent substances are in time, and so let us turn to the criterion of greater scope.

Scope

The criterion of greater scope requires us to prefer the theory about the nature of time that explains more to the one that explains less.

It may seem that the perdurance theory does have a greater scope, because it explains at least one phenomenon ontologically that the endurance theory simply assumes. It explains ontologically why permanent substances are in time by showing how they are constituted by momentary substances and relations among them. But this claim to have an ontological explanation of substances being in time does not stand up, for two reasons.

First, it is ad hoc. Nothing is explained by the assumption that permanent substances are constituted by momentary substances and relations among them except their being substances that exist at every moment in the history of the world. To postulate infinitely many ontological causes to explain a single aspect of the world is to explain the least with the most, the opposite of the empirical criterion. To be sure, the endurance theory does not explain this aspect any better. But there is nothing to prefer over the assumption that existence itself is in time.

Second, there is an aspect of this phenomenon whose possibility the perdurance cannot explain. That aspect is how the present moment is different from all the other moments in the history of the world, both past and future. It is something for which the endurance theory can account. And the failure even to account for it (that is, the failure to explain its possibility) means that the perdurance theory is falsified by it.

Endurance theory can account for the fact that one moment in the history of the world stands out as different from all the others, because it holds that only the present moment exists. The present is different from the past and the future in the most basic way, as far as ontology is concerned, because the present exists, while the past and future do not. That is what it means to hold that existence itself is in time. (This is not to explain the phenomenon of the present ontologically, because it is simply what the endurance theory assumes about the nature of existence. But the endurance theory does not have to deny that present is different from the past and future.)

The perdurance theory, on the other hand, cannot even account for the fact that the present stands out as different from all the other moments in the history of the world. It holds that all the moments in the history of a permanent substance exist in exactly the same sense, and so there is nothing ontological that can distinguish any one moment from all the rest that help make up its history. To be sure, the perdurance theory can say how any moment in the history of a permanent substance that is taken as the present differs from those that occur earlier and those that occur latter, for its momentary substances are all related to one another in a certain order. But it has no way to single out any moment in the history of a permanent substance as "now."

This blindness to the present is implicit in what the perdurance theory says about the nature of existence and time. Instead of taking time to be an aspect of the nature of existence, it takes time to be part of the structure of what exists, that is, a certain kind of relationship that exists among its momentary substances. It sees time as a dimension of what exists, much like spatial dimensions, and thus, time contains different moments in the same way that space contains different point, which means that all moment are contained in the same way.

Thus, far from explaining why permanent substances are in time, the perdurance theory cannot even explain the possibility of the most basic aspect of it. Indeed, the phenomenon of the present being different from the past and future would seem to show that the perdurance theory is false.

What the perdurance theorists can do, however, is explain away the phenomenon. That is, it can explain why we experience the present as being different from all the other moments by holding that it is just an appearance that holds for each and every moment in the history of beings like us. We are rational beings, capable of reflection, and it is by reflecting on our experience that we come to believe that the present moment is different from the past and the future. But if the perdurance theory is correct, each of us is just a set of momentary substances that makes up a personal history. Thus, it is possible to hold that the essential nature of every momentary substance constituting a being like us includes the appearance that that moment in one's history is the present and, thereby, different from all the moments in the past that may be remembered and all the moments that may be anticipated. That is, each moment in the life of a reflective subject includes the subjective appearance that it is present, even though it is just another momentary substance that exists non-temporally.

But this is not to explain the present. It is to claim that our sense of the present is an illusion. That is surely an alternative that we want to avoid, if possible, for it is ad hoc. Anything found in the world could be explained away the same way, that is, explained as a mere appearance to the subject by holding that it is actually part of his essential nature as a substance. If it is possible to explain our sense of the present being different from the past and the future in a way that makes it true, we must prefer the theory that does so. Hence, the empirical method requires us to prefer the endurance theory on the grounds that it explains more than the perdurance theory.ii

This point can be seen more clearly if we consider how the present being different from the past and the future is something found in the world by perception, not just by reflection on how it seems to us. We perceive change in the natural world, and if we articulate the beliefs implicit in such perceptions, we find that what we believe is that certain properties go out of existence and other properties come into existence as time passes.

Consider, for example, a bus passing by us on the street. The property of approaching us goes out of existence as the property of being in front of us comes into existence, and then the property of being in front of us goes out of existence as the property of moving away from us comes into existence. That is how we perceive change in the natural world, and it implies that the properties that the bus had in the past do not exist any longer, and that the properties that it will have in the future do not exist yet. That is what we mean by their coming into existence and going out of existence as time passes.

To be more precise, reflecting on our observation, we find that the experience involves past, present and future. At the moment we see the bus is in front of us, we remember seeing it approach and anticipate its moving away. Were the immediate past and future not part of our experience, we could not observe that the bus is moving. But while the present is seen as existing, the past and future are seen as not existing, albeit for opposite reasons. The past event is seen as not existing because it is over, while the future event is seen as not existing because it has yet to happen.

Thatonly the present exists may be only implicit in the observation. But that does not mean that it is not part of what we observe, only that we have not formulated that aspect as a sentence. The belief that the bus’s past and future do not exist now is as much part of the observation of the bus’s motion as the belief that that the bus is a distinct object in space is a part of the observation of the bus itself. It is not surprising, therefore, that this is called the ordinary view of the nature of time. It is what the “man in the street” would say about the past and future if asked about their existence (see, for example, Putnam [1967], p. 240).

The perception of change as "real" in this sense discloses something about the world that cannot be explained by the perdurance theory, because it must deny that any properties come into existence or go out of existence over time. The perdurance theory holds that every moment in the history of every substance exists in exactly the same sense, and so the properties that hold at earlier moments still exist in the same sense as the present, and the properties that hold at latter moments already exist in that sense.

Again, the only way that the perdurance theory can account for this perceived fact about the world is to deny that it is a fact and to hold that what we think is perception of an independently existing world is just an illusion. That is, its defenders can hold that each of the momentary substances making up the histories of beings like us involves, as part of its essential nature, the appearance that change really takes place as time passes. That would mean that, relative to any given moment, we perceive the past and future states of the world as not existing, even though, in fact, they do.

But this is, once again, to explain away the phenomenon, not to explain it ontologically. It could be used to explain anything found in the world, and thus, it should only be invoked, if it is not possible to explain phenomena as what really exists. The perdurance theory has no alternative, because if change is real in this sense, it is false. But we have an alternative, because the perception can be accounted for by the endurance theory.

The perdurance theory does not, therefore, have greater scope than the endurance theory. Its explanation is ad hoc, and what is worse, it is falsified by the phenomenon that it claims it alone can explain, unless we accept further ad hoc assumptions that make the phenomenon illusory.

Nor do any of the arguments for the perdurance theory offered by defenders of the so-called tenseless theory of time give us any reason to accept it.iii

The empirical method requires us, therefore, to prefer the endurance theory over the perdurance theory. It is simpler in both relevant ways (the fewest and simplest ontological causes), and it has a larger scope (in the sense that it can, at least, account for our sense of the present and our perception of change as really occurring in time). It clearly explains more with less.

Nor are the basic aspects of the world that only the endurance theory can explain trivial. The ability to explain change by the endurance of substances through time is the foundation for explaining regularities about change ontologically. If ontological philosophy had to accept the perdurance theory, it would not be able to show the ontological necessity of the connection between cause and effect in efficient cause explanations. Nor would it be able to demonstrate the ontological necessity of global regularities, on which most of the new ontologically necessary truths depend. Without the endurance theory, ontological philosophy would not be a new way of doing philosophy.

This does not necessarily mean that it is true. It is only to say that we must prefer it, if it is possible, for it may turn out that there are other things found in the world contradict the endurance theory. That is what contemporary Einsteinian believe, as we shall see when we take up spatiotemporalism, and thus, they will have to be answered before we can be confident about the truth of the endurance theory.

Space

Naturalists believe that the world is just what is in space and time, and having seen that we should, if possible, believe that substances endure through time, the next question is what we should believe about the nature of space.

Possible explanations

There are basically three alternatives: spatiomaterialism (the belief that space and matter are both substances), materialism (and the belief that space is just spatial relations), and spacetime substantivalism (the belief that the substance that exists in addition to matter is not space, but spacetime). Though the following argument would have to be reconsidered, of course, if a fourth alternative turns up that is simpler than all of these, that does not seem likely. After describing each of these alternatives, I will consider which offers the best ontological explanation of the natural world.

Spatiomaterialism

By "spatiomaterialism," I mean the belief that the substances constituting the world include space as well as matter. It postulates matter, because it assumes that there are substances in space that obey the basic laws of physics. But it also postulates space as a substance. ("Substantivalism" is the traditional name for the view that space is a substance, though as we shall see, substantivalism about space should be distinguished from substantivalism about spacetime, the kind of substantivalism that is taken seriously today.) Finally, spatiomaterialism assumes that the bits of matter are all contained by space in the sense that each of them coincides with some part(s) of space or other. That is how these two substances exist together as a world, and thus, it is the basic relationship that spatiomaterialism assumes as the other part of every ontological cause.

Spatiomaterialism assumes that space is a substance by our definition, for it assumes that each part of space has both the essential and the existential aspects of the nature of substance as substance. The parts of space are all the locations in a single, three dimensional space.

Each part of space has both aspects of the existential nature of a substance, temporality and particularity, because in addition to never coming into existence and never going out of existence, each location in space has an existence that is distinct from from all the other locations in space (not to mention from any bits of matter that may coincide with it). Though spatiomaterialism is compatible with both theories about the nature of time, we shall take it to include the endurance theory, for as we have just seen, the endurance theory is the best ontological explanation of the temporal aspect of substances. (Only the endurance theory is compatible with the present being different from the past and the future, and the perdurance theory even denies that change involves properties coming into existence and going out of existence.)

Though parts of space have the same kind of existential nature as bits of matter, parts of space have the opposite essential nature. Whereas bits of matter exist independently of one another in the sense that each could still exist, even if the other bits of matter did not exist, parts of space depend on one another in the sense that no part of space can exist without all the other parts of space. The essential nature of each part of space includes having geometrically coherent relations to every other part of space. That is, the essential nature of each part of space is defined by its location relative to all the other parts. Thus, parts of space exist only if space exists as a whole. (Indeed, it is the wholeness of space and what it contributes to the natural world that is the key to almost all the new necessary truths based on spatiomaterialism.)

In other words, space has an opposite essential nature from matter because its parts are not prior to the whole. Since each bit of matter is capable of existing independently of all the other bits of matter in the world, there is a sense in which the parts of matter are prior to the totality. But that is not true of space, because no part of space can exist without all the other parts of space. That does not mean, however, that, in the case of space, the whole is prior to the parts, because the whole of space cannot exist without all its parts. Space is whole in a unique way, as we shall see, and one indication of its uniqueness is the way that the parts of space and the whole are equally basic.

Spatiomaterialism assumes that space has a three dimensional Euclidean structure. Though non-Euclidean geometries can be described coherently, they are not as simple as Euclidean geometry. Euclidean geometry is assumed here, because, as it turns out, there is no reason to doubt that the simplest alternative is true.

To be sure Einstein's general theory of relativity implies that spacetime can be curved and can, therefore, be represented only by a non-Euclidean geometry. But what it implies is curved is not just space, but spacetime, and as we shall see (in Change: General theory of relativity), curved spacetime can be explained as an aspect of space as a substance with a Euclidean geometrical structure (basically by variations across space in the velocity of light relative to space).

The version of spatiomaterialism considered here will also assume that space is infinite.

The infinity of space will be assumed, because that is the simplest nature space can have. Even though the parts of space cannot exist without one another, they are distinct substances, and the essential nature of each particular spatial substance is necessarily unique in the sense that it involves a unique relationship to every other particular spatial substance. But the simplest assumption is that all the parts of space have the same kind of essential nature, that is, the same kind of relation to other parts of space as every other part of space. However, if the parts of space all have the same kind of essential nature, a Euclidean spatial substance must be infinite as a whole. For if there were an end to space, no two parts of space could have the same kind of essential nature. Each part would have a different relation to the edge of space (if makes sense at all to talk about an end to space). Thus, the simplest form of spatiomaterialism would hold that space is infinite.

To be sure, most astronomers and astrophysicists currently assume that space is finite, because its finitude is entailed by the use of the general theory of relativity to represent the big bang and the subsequent expansion of the universe. And it would be possible, if necessary, to formulate a version of spatiomaterialism in which space is finite. But it would be a more complex ontological cause than is assumed here, for its parts would have to have systematically different kinds of essential natures. And it may not turn out that the big bang theory is true, as argued in Change: Cosmology.

Notice, however, that the infinity of space is twofold. There are finite distances in space, for that is entailed by its having a geometrical structure, and there are opposite way ways in which it is possible to generate an infinite series. It is possible, in one way, to keep doubling its size, step by step, forever in the same direction, and it is also possible to keep dividing it in half, step by step, for ever. The former means that space is infinite in extent, whereas the latter means that space is continuous (or that parts of space are connected continuously). Both kinds of infinity are assumed here as simply part of the essential nature of space as a substance.

The continuousness of space means that the number of points on a finite line is greater than the number of whole numbers, which is already infinite. Thus, the points on a line are said to be nondenumerable. (It can be shown, furthermore, that there are just as many points on a finite line as there are points on a finite plane and as there are points in a finite volume.) This can seem puzzling, if it is assumed that lines are made up of points, because more than an infinite number of points would be required to make up a line. This may be problematic for mathematics, but not for ontological philosophy, because we do not assume that space is made up by combining points at all. What is essential about points in space is their distances (and directions) from one another (or the metric of their geometrical relations), not how many points there are in any finite distance. In other words, space is not made up of points in the way that ordinary material objects are made up of simpler bits of matter, that is, by assembling them alongside one another; indeed, according to spatiomaterialism, that way of putting bits of matter together as a whole is something that is possible only because the bits of matter all coincide with parts of space. Rather space is made up of points in the sense that the points all have as their essential natures determinate distances from one another in all three dimensions as parts of a single whole space. Indeed, points can be picked out at all only because the parts of space have such spatial relations to one another. That is, once again, the wholeness of space.

Time has a twofold infinite nature like space. Given any finite period of time, it may be doubled forever or divided forever. Thus, not only does time go on eternally, but it also flows continuously (that is, the moments in time are continuous with one another). And that is likewise simply the nature of time. (Two moments in time are related by the amount of time that passes between them, not the number of moments between them; the temporal metric is what makes it possible to pick out moments in time.) The direction of time, however, introduces an asymmetry that is not found in space, separating the issue about whether time extends infinitely toward the past from the issue about whether it extends infinitely toward the future. Though the big bang theory denies the former, it leaves open the possibility that the future may be infinite. We will, however, proceed on the assumption that time is infinite in both directions, postponing discussion of the big bang until Change: Cosmology.

The belief that space is a substance may have been what the ancient atomists, Leucippus and Democritus, meant by insisting that the arche, or "first principle," includes two elements, both atoms and the void. In other words, the usual interpretation of atomism, mentioned in Ontology, may be mistaken. What they meant by the void may not have been merely a kind of stuff between atoms that is so subtle that, unlike other atoms, atoms can move through it without resistance. They may have meant that the void is something that exists not only in between atoms, but also underlies each and every atom. This way of thinking about the nature of space may have been obscured by the lack of any better way than "the void" to refer to what they meant. That is, arguably, one of interpreting the ancient atomists, which would make them the discoverers of the view that is assumed here.

Notice that it is not inconsistent to hold that space is contained by space or exists in space, though it holds for a different reason from matter. It is not inconsistent, because the parts of space are substances and each part of space is, indeed, is located in space or is contained by space in the sense that it has a location relative to all the other parts of space. Indeed, that is part of the essential nature of each part of space. Bits of matter are also contained by space or in space in the sense of having a location relative to other bits of matter. But according to spatiomaterialism, that is not part of the essential nature of matter. Nor is it simply how bits of matter exist together as a world. It is, rather, a result of each bit of matter coinciding with some part(s) of space. It is space that gives bits of matter their spatial relations to one another. Given that space and matter are both ontological causes, the ontological cause of bits of matter all having spatial relations to one another is the basic relationship by which the two opposite substances exist together as a world. It is because the parts of space are contained by space that the bits of matter coinciding with any part are contained by space.

Spatial relationism

By "spatial relationism," I mean the belief that matter is the only kind of basic substance in the world and that space is nothing but the relations that hold among bits of matter. Matter is assumed to have the essential nature described by the basic laws of physics, and spatial relations can be explained in one way or another as how bits of matter exist together as a world. And we will take spatial relationism to include the endurance theory of time (as we did spatiomaterialism), since that is the best explanation and spatial relationism is compatible with it.

Spatial relationism is basically a negative thesis. It is the denial that space is a substance distinct from the material substances in the world. It denies that space exists independently of matter by holding that spatial relations have the same status as properties of matter.

It is not necessary to postulate any substances in addition to matter in order to account for spatial relations, any more than it is necessary to postulate additional substances to account for the properties of material substance. They can be understood as nothing but aspects of the material substances postulated. Just as (monadic) properties are aspects of the substances themselves taken separately, the relations among them are aspects of their existence together as a world.

There are subtly different versions of spatial relationism, as mentioned in Ontology: Nature of relations, depending on this ontology explains the possibility change in spatial relations. How the substances postulated exist together as a world is the most basic relationship that an ontology must assume in addition to the substances to explain how they exist together as a world. That basic relationship determines how substances can be combined and recombined as time passes in order to explain ontologically the diversity and change in nature. Thus, if spatial relations are nothing but how material substances exist together as a world, their basic relationship involves change. That is possible, because the basic relationship among the material substances can be simply having spatial relations of some kind or other, not having any particular spatial relations. That basic relationship does not change even when the particular spatial relations among material substances are changing. But since particular spatial relations do change, there must be some way to explain the possibility of such change. (And since spatial relations change in regular ways, it must also be able to account for those regularities.)

It is possible to hold, on the one hand, that the basic relationship by which material objects exist together as a world has a temporally complex nature. "Having spatial relations" would be defined by describing the regularities in how the spatial relations between material objects change, for example, that they change only continuously over time, that is, by motion. (Material objects do not flit about discontinuously form one place to another.) This would be to define the essential nature of the basic relationship among material substances dispositionally, much as the essential natures of material substances are defined dispositionally when they are assumed to obey the basic laws of physics, that is, in terms of the regularities in how they move and interact.

On the other hand, it may be possible to hold that the basic relationship is temporally simple. "Having spatial relations" would be understood merely as a kind of condition that holds among material objects at each moment as it is present, and the change that occurs in spatial relations would be a result of the essential natures of the material substances. That is, the essential natures of the material substances would be temporally complex, as when they are defined in terms of the basic laws of physics, and the ways in which spatial relations change over time would simply be a consequence of how the basic laws of physics work out.

There are problems with this view, however. One is that the laws of contemporary physics include quantum mechanics, and since they do not describe a fully deterministic process, spatial relations cannot be fully determined by the basic laws of physics (unless there is a so-called hidden variable involved).

But even if the laws of physics were deterministic, there is another problem, for the laws of physics can determine the spatial relations that hold of bits of matter at any one moment only if their spatial relations at some other moment is given. Since the past determines the future, the particular spatial relations may have to be fixed for some earlier point in the history of the universe, presumably at the beginning of the world, such as the Big Bang or when God created it. In any case, the basic relationship would not be temporally simple after all, for having spatial relations would not be a condition that holds only at the present moment, but must include all the particular spatial relations that hold at some other moment in the history of the world.

In either case, however, spatial relationism holds that space is nothing but spatial relations, where those relations are, ontologically, just the basic relationship by which material objects exist together as a world, that is, ultimately, an aspect of the material substances themselves.

Leibniz denied that space is a substance. (And he debated the issue with the Newtonian, Samuel Clarke. See Earman.) But spatial relationism as defined here should be distinguished from the kind of spatial relationism entailed by Leibniz's ontology. Leibniz did not take spatial relations to be how the basic substances exist together as a natural world. The substances Leibniz postulated to explain the natural world were monads, or minds of various kinds, and he explained spatial relations as how monads appear to one another, that is, as ideas in those minds. The way that monads existed together as a natural world was by each being created by God, though Leibniz did hold that the appearances of spatial relations in all the different monads fit together coherently as a natural world.

In any case, defenders of Newton were never able to refute spatial spatial relationism, because they assumed that the only way to prove that space is a substance is by empirical science, that is, by confirming some crucial prediction. Even Newton's theory did not provide any way to measure absolute rest or motion, and all the same phenomena (including the famous rotating bucket; see Earman, pp. 61-90) could also be explained on the assumption that space is nothing but spatial relations among material substances (by taking into account spatial relations to distant stars).

According to Ryansiewicz, the classical debate between spatial relationism and substantivalism about space is no longer meaningful in the context of contemporary physics. But that position is compellingly refuted by Hoefer (1998)

Spatiotemporalism

Spatiotemporalism agrees with spatiomaterialism that the spatial relations among bits of matter depend on another substance, in addition to matter. What makes it different from spatiomaterialism is that it takes that substance to be spacetime, rather than space. In fact, that makes it fundamentally different from both other theories. Spatial relationism (or materialism) and spatiomaterialism can both accept the endurance theory of time (and both do, as we they have been defined here). But the belief in spacetime as an ontological explanation of the world entails the perdurance theory of time. That is what it means, when speaking ontologically, to deny that space and time are absolute. Though this view is usually called "substantivalism about spacetime," I will call it "spatiotemporalism" in order to bring out the contrast with spatiomaterialism and spatial relationism.

This preference for spatiotemporalism over spatiomaterialism is justified by Einstein’s relativity theories. Minkowski introduced the notion of spacetime in 1908 as a way of summing up what Einstein’s 1905 special theory of relativity implied about the world, and he predicted that it was the beginning of the recognition that space and time are not independent of one another. Einstein then took spacetime as basic in constructing his general theory of relativity, that is, in his explanation of gravitation as a result of a curvature imposed on spacetime by large accumulations of matter in it. And since spacetime must be a substance in order for it to interact with matter in that way, it is now common for philosophers of spacetime to hold that spacetime is the opposite kind of substance that exists in addition to matter and explains why bits of matter have spatial relations. (See Friedman and Earman, for example.)

The basic nature of spacetime is determined by Einstein's special theory of relativity. Einstein called it a theory of "relativity," because it holds that the places and times at which events occur depend on the inertial frame of reference from which they are observed. Different inertial frames have different velocities, and according to Einstein's special theory, they assign different spatial and temporal coordinates to events in the universe. For example, observers on two different inertial frames that happen to be located at the same point at the same time will have different views about which events in the histories of distant objects are occurring at the same time their paths cross. Einstein's special theory holds that their views are equally true, and that implies that the distant objects actually exist now at both moments in their histories. (With additional inertial observers, this means that the distant objects must exist equally at all the moments in their histories that can be said to be simultaneous with different inertial observers here and now). This loss of agreement about the simultaneity of events at a distance might seem to be just a theoretical problem about the nature of objects at a distance, but since Einstein's special theory holds that all possible inertial frames are equivalent, it has the same implications for inertial observers here and now. That is, observers on different inertial frames observing us from a distance would similarly disagree about which moment in our history is simultaneous with their present moment, and thus, in order for all their views to be true, we must actually exist equally at different moments in our history, indeed, equally at all of them. This is to deny presentism, because it forces us to believe that our past and our future exist in the same way as the present.

It is the loss of agreement about simultaneity at a distance that makes the belief in spacetime so problematic. To be sure, no problems arise for physics, because it is always possible to predict from one inertial frame what observers on all the others will say. But when spacetime is understood ontologically, that is, as describing the basic nature of space and time, the denial of simultaneity at a distance entails the perdurance theory of time. What really exists are not substances with spatial relations enduring through time, but a kind of eternal, unchanging four-dimensional world whose parts are spread out not only in the spatial dimension, but also in the temporal dimension. Since the world is constituted by all its parts, different moments in the history of each permanent substance are different parts of the world in exactly the same sense that different permanent substances (including different locations in space) are different parts of the world.

The substantival nature of spacetime is entailed, at least for scientific realists, by the interaction between its curvature and matter that explains gravitation according to Einstein's general theory of relativity. Spacetime could not be what causes material objects to exhibit gravitational acceleration unless it were something that exists in addition to those material objects. This ontological interpretation of spacetime, or substantivalism about spacetime, is what I mean by "spatiotemporalism." It holds that time is ontologically on a par with space (by contrast to spatiomaterialism, which holds that matter is ontologically on a par with space). That is the perdurance theory of time. To hold that time is just another dimension relating parts of substances geometrically is to hold that just as different places in space all exist in the same way, so different moments in time all exist in the same way. This implies that ordinary, permanent substances (that is, substances with a temporal aspect to their existential aspect as substances) do not endure through time, but perdure over time.

The best ontological explanation of space

If we follow the empirical method, we will believe the theory about the nature of space that provides the best ontological explanation of the natural world. That is clearly spatiomaterialism, if it is possible (in particular, not falsified by the any phenomena covered by contemporary physics), because it is better than spatial relationism and better than spatiotemporalism. And since, as I will show, physics does not make it impossible, naturalists who follow the empirical method in deciding which ontology to believe will accept spatiomaterialism.

Spatiomaterialism is better than spatial relationism

It may seem at first that spatial relationism is a better explanation of space than spatiomaterialism, because it postulates only one kind of basic substance, rather than two. Spatial relationism is basically just a kind of materialism that has made its beliefs about space explicit, whereas spatiomaterialism holds that space is a substance existing independently of matter which contains all the bits of matter in the world. On grounds of simplicity, therefore, it might seem that we should prefer spatial relationism to spatiomaterialism.

Simplicity is not, however, the only empirical grounds for preferring one theory over another. There is also the criterion of scope, and by it, spatiomaterialism is clearly superior. Thus, if spatial relationism were simpler than spatiomaterialism, there would be a trade-off between them which keeps the empirical method from choosing between them.

But that standoff is not the final word, because when we look closer at the criterion of simplicity, we will find that spatiomaterialism is at least as simple as spatial relationism, if not simpler. Simplicity is not a simple criterion, for there are two ways in which ontological explanations can be simpler (not only by the number of ontological causes, but also their natures), and by one of them, spatiomaterialism is clearly simpler than spatial relationism. There is, therefore, a standoff on grounds of simplicity, and that makes the criterion of greater scope decisive. Empirical ontologists should prefer spatiomaterialism.

But a decision in favor of spatiomaterialism is even more clear-cut than this may make it seem, for the way in which spatiomaterialism is simpler also reveals another way in which it has a greater scope. In the end, there is no doubt that spatiomaterialism explains more with less. The empirical method will require ontologists, therefore, to prefer spatiomaterialism over spatial relationism. Let us begin by considering the issue about the scope of explanation.

Scope

Spatiomaterialism explains more about the natural world than spatial relationism, because it explains why bits of matter have spatial relations, whereas spatial relationism merely assumes that they do.

Space is a substance with an opposite essential nature from matter, and so if it contains all the bits of matter in the sense that each bit of matter coincides with some part of space or other, the bits of matter acquire their spatial relations from the spatial relations that already hold among the parts of space with which they coincide. That is, space and matter work together as ontological causes to produce spatial relations. Having spatial relations is not just an ontological assumption about bits of matter, since three different ontological assumptions are needed to explain it.

By contrast, spatial relationism does simply assume that bits of matter have spatial relations. To be sure, materialism can "account for" spatial relations; the fact that bits of matter have spatial relations does not show that materialism is false (as presentism and the fact of real change falsify the perdurance theory of time). But that is not to explain why bits of matter have spatial relations. Thus, since we are seeking the best explanation, we must prefer the theory which explains more.

Materialists may demur by insisting that postulating space to explain spatial relations is ad hoc and, thus, not an explanation at all. Though it may appear to be an explanation, they will hold that substantivalism about space is equivalent to assuming that bits of matter have spatial relations. Indeed, it is the same assumption that spatial relationists make, except for being disguised as a substance. Substantivalism about space merely reifies spatial relations.

This objection will not stand, however, because spatial relations are not all that substantivalism about space explains ontologically. It also explains, together with matter, the possibility of change (as well as certain ontologically necessary truths about how bits of matter change, as we shall see later).

The assumption that all the bits of matter are contained by space as a substance implies only that each bit of matter coincides with some part of space or other. But that leaves open which place it is. Moreover, parts of space are connected with one another continuously, so that there are no gaps, so to speak. That is just the essential nature that spatiomaterialism takes space to have. Thus, as space and matter endure through time, it is possible for spatial relations among bits of matter to change, because bits of matter can move across space over time without giving up any of spatiomaterialism's assumptions. The continuousness of time works together with the continuousness of space to make motion possible. Neither space nor matter changes their essential natures, and the bits of matter are always contained by space, always deriving their spatial relations from space. (This way of explaining motion ontologically also implies that motion is the only way that bits of matter can change their spatial relations as time passes. See in Local Regularities under Change.

Since substantivalism about space explains something more than just why bits of matter have spatial relations, it is not ad hoc, but genuinely explanatory. Spatial relations are only one of several basic phenomena explained by spatiomaterialism.

This is to explain the possibility of change by motion, but it is also possible for spatiomaterialism to explain the possibility of change in another way: by interaction. That is how motion changes, as we shall see. Being in space, bits of matter can move to the same location, and when they do, they are in a position to act on one another, because they not separated from one another by space. (The impossibility of action at a distance -- that is, with spatial substances separating the bits of matter -- is also shown in Local Regularities under Change.)

Thus, since spatiomaterialism can explain the possibility of both motion and interaction, that is, both kinds of change described by the laws of physics, its explanation of spatial relations is not ad hoc. In other words, the greater scope of spatiomaterialism is shown by its ontological explanation of at least three basic facts about the natural world that are just assumptions of spatial relationism -- that bits of matter have spatial relations, that they can change by motion, and that their motion (and other properties) can change by interaction.

This may not be an original argument for substantivalism about space. The way in which space makes motion and interaction possible may have been what Leucippus and Democritus were getting at when they insisted on postulating the void as an element along with the atoms, though that is still a controversial interpretation of ancient atomism.

Simplicity

Since empirically minded ontologists must prefer ontologies that explain more, they have a good reason to prefer spatiomaterialism over spatial relationism. But materialists might hope for a standoff between these two ontologies at this point. The empirical method might fail to choose between them. Although the criterion of greater scope favors spatiomaterialism, the criterion of simplicity may favor spatial relationism, because spatial relationism postulates only one kind of basic substance, not two. Simplicity is not, however, a simple criterion, and when we consider both ways in which explanations can be simple, we will see that there is also a way in which spatiomaterialism is simpler than spatial relationism.

Such a standoff on grounds of simplicity would force ontologists to prefer spatiomaterialism, because they are equal except for the greater scope of the latter. But the empirical method is even more decisive than this suggests, because the way in which spatiomaterialism is simpler is another way in which spatiomaterialism explains more than spatial relationism. Thus, it will be clear in the end that, even though spatiomaterialism postulates two basic substances, rather than one, it explains more with less.

The reason that materialism is not necessarily simpler than spatiomaterialism is that simplicity is judged not only by the number of basic ontological causes, but also by the simplicity of their natures. That is, materialism may not be simpler than spatiomaterialism, even though it postulates only one kind of basic substance, because it may require either matter or the basic relationship among them to have a more complex essential nature than spatiomaterialism. This is how it will turn out, and in order to see why, let us look more closely at the basic relationship assumed by materialist ontology.

The basic relationship among bits of matter, according to spatial relationism, is that bits of matter all have spatial relations with one another. But we are assuming that they are all geometrically coherent, that is, that their spatial relations all fit together as parts of a three dimensional world. That assumption about their basic relationship can be understood in two different ways, and together they pose a dilemma for spatial relationism, for both have consequences that make spatial relationism more complex than spatiomaterialism.

"Having coherent spatial relations" may be taken as an aspect of the spatial relations that all the particular bits of matter have at the present moment, or it may be taken as an aspect of their particular spatial relations at every moment in the history of the world. In the first case, materialism must explain why bits of matter have coherent spatial relations at every moment, and the only way of doing so undermines the way that physical explanations are ordinarily understood. In the second case, the basic relationship of materialism must have a temporally complex nature, for its essential nature must include a fact about the world that spatiomaterialism explains by ontological causes that are temporally simple. Let us consider each horn of this dilemma in turn.

Notice, by the way, that in both ontologies, the basic relationship is not the particular spatial relations that bits of matter actually have, but an aspect of those particular spatial relations. For materialism, it is the geometrical coherence of those spatial relations, whereas for spatiomaterialism, it is that those spatial relations come from bits of matter coinciding with parts of space. The particular spatial relations that bits of matter actually have are taken by both theories to be something that can be known only by experience of the world.

Temporally simple basic relationship. The basic relationship assumed by spatiomaterialism is temporally simple. It assumes that the way that space and matter exist together as a world right now is by each bit of matter coinciding with some part of space or other, and that is temporally simple, for its two basic substances can have that relationship completely at one moment in the existence of the world. And this assumption needs to be made only about the present moment, because if all the bits of matter are contained by space at the present moment, then the fact that substances endure through time, never coming into existence and never going out of existence as time passes, entails that they have the basic relationship at every other moment. There is no way for a bit of matter to escape from space altogether, for it exists now as part of the same world by coinciding with some part of space or other and space endures through time along with matter. For the same reason, it could not get into space, if the bit of matter did not already coincide with some part of space or other.

The basic relationship assumed by spatial relationism can also be temporally simple. It is the assumption that bits of matter have coherent spatial relations, and that relationship can hold completely at any moment in the history of the world. But unlike spatiomaterialism, if that basic relationship is assumed to hold at the present moment, it does not necessarily hold at all other moments in the history of the world. It is conceivable that bits of matter would move and interact in ways that would give them spatial relations that are not geometrically coherent. (Similarly, it is conceivable that the present spatial relations are a result of the motion and interaction of bits of matter from earlier states in which their spatial relations were geometrically incoherent.)

It is conceivable, for example, that when matter of a certain kind is given the shape of a cave, the cave from inside is larger than the cave from the outside. That is, when measuring rods are taken inside the cave and used to measure how large the cave is, the internal distances measured turn out to be greater than the size of the cave when it is measured from the outside.

It might be argued that such spatial relations are not geometrically incoherent, but merely show a curvature about space. They are only incoherent according to Euclidean geometry. But postulating non-Euclidean geometry will not always preserve geometrical coherence. For example, suppose that when matter of a certain kind was shaped into a cave and extended into a tunnel, another entrance cut in the distant wall of the cave would open up in some far distant location in three dimensional space.

Topology explores many such possible connections among regions of spatial relations, and we need only think of them as being the effect of shaping matter in certain ways in order to conceive how the motion and interaction of bits of matter could lead to their having incoherent spatial relations.

In fact, spatial relations do not become geometrically incoherent in such ways, and so having geometrically coherent spatial relations at every moment is a basic aspect of the world than an ontology needs to explain. Now, spatial relationists may insist that they can explain this aspect of the world by the essential nature of matter. They assume that the essential nature of matter is defined by the basic laws of physics, and so they can argue that, if spatial relations are geometrically coherent at the present moment, they will be geometrically coherent at all moments in the future (and in the past), because those future (and past) spatial relations are determined by those bits of matter moving and interacting according to the basic laws of physics. Their geometrical coherence is, in other words, a consequence of the nature of matter. The reason that spatial relations will be geometrically coherent at other times, if they are geometrically coherent now, is that it is physically necessary.

This possibility is suggested by the structure of explanations in physics. As explicated by the deductive-nomological model, the basic laws of physics together with initial and boundary conditions make it possible to predict (or retrodict) any future (or past) state. Thus, if we take momentum to be a property of the bits of matter, the particular spatial relations among bits of matter at any one moment will determine their spatial relations at any other moment. Hence, they will be coherent at every moment, if spatial relations are coherent now.

Notice that this way of explaining why spatial relations are geometrically coherent depends on complete determinism, such as was assumed in Newtonian physics. (It was Laplace who first argued that the laws of Newtonian physics made this possible.) It is not, however, compatible with quantum mechanics, if Heisenberg's principle is taken to represent an indeterminism about what happens in the world as bits of matter move and interact, for such indeterminism would leave plenty of room for bits of matter to acquire incoherent spatial relations. It is, of course, possible that Heisenberg's principle represents merely an inevitable incompleteness about physical theory. There could be a hidden variable that makes physical processes deterministic, though it cannot be measured. But most naturalists would be surprised to find that they are committed ontologically to such an interpretation of quantum mechanics by their acceptance of materialism (that is, reducing space to spatial relations).

Even if physical laws are deterministic enough to explain why bits of matter always have coherent spatial relations, there is an intolerable cost to be paid in our understanding of how physical processes take place. Physicists ordinarily think of what happens in nature as a result of how bits of matter move and interact in space, where their spatial relations are one factor that combines with their motion and the forces they exert as a different kind of factor to determine what happens to them. But that is not possible, if the regularities described by laws of physics are what make spatial relations coherent in the first place, for then there is no way to explain how spatial relations work together with motion and forces as different kinds of efficient causes. Both kinds of factors are simply contingent aspects of bits of matter, and ontologically, they have the same status.

When material objects exert forces on one another, for example, when a planet exerts a gravitational force on a material object near its surface, we naturally think of the acceleration of the object as having two kinds of efficient causes: its distance from the planet and the force exerted by the planet. If object were released farther away, the same force would give it more momentum before colliding with the planet. And if the force were greater where it was released, the object would also have more momentum before colliding. We think of spatial relations and forces as two different kinds of efficient causes determining the later state. But if the basic laws of physics are supposed to explain why bits of matter have coherent spatial relations in the future, there is no way to distinguish the effect of forces from the effect of spatial relations. Instead, laws of physics must be seen as operating on the spatial relations, velocities, and forces that exist at one time to determine new spatial relations, velocities, and forces at a later (or earlier) time. Though what happens is predictable, the cause is not the planet's gravitation force acting on the object across space, because there is no way to distinguish the effect of the space from the effect of the force. Both depend on the regularities described by the laws of physics in the same way.

Likewise for motion. When a material object has a certain velocity, we think of its future spatial relations to stationary material objects as a result of its motion through a space that is already there. Its momentum is something that the object has, and we ordinarily see its future locations as being determined by its momentum together with its location in a space that is somehow independent of it. But that way of conceiving physical causes must be given up, if the conservation of momentum helps cause bits of matter to have coherent spatial relations. The future spatial relations are not caused by moving through space. They are caused by its motion and its past spatial relations, changing according to a basic law of physics which is taken as defining the nature of matter.

This form of spatial relationism makes almost everything that happens in the world depend on the nature of matter, rather than on what it assumes about the nature of spatial relations (namely, that they are geometrically coherent at the present moment). . This can also be seen how materialism explains other aspects of motion and interaction that spatiomaterialism explains by substantival space. Whether or not it is ontologically necessary, it is true that bits of matter do not change spatial relations by flitting about from place to place discontinuously, but only by moving across space as time passes. Spatial relationists would deny that this depends in any way on the nature of spatial relations. They would explain this regularity as just another aspect of the regularities described by the basic laws of physics, which define the nature of matter. The same holds for the materialists' explanation of why bits of matter do not act one one another at a distance.

In other words, to assume that having coherent spatial relations is a basic relationship that holds only at the present moment is to assume, in effect, that matter has an essential nature that is more complex temporally than the matter assumed by spatiomaterialism. Materialists have to attribute more aspects of what happens in the world to the nature of material substance as an ontological cause than do spatiomaterialists. The greater complexity of the essential nature of matter is what contradicts the claim that materialism is simpler than spatiomaterialism.

Temporally complex basic relationship. Instead of making the coherence of spatial relations a consequence of the basic laws of physics, materialists can take the basic relationship by which bits of matter exist together as a world to be having geometrically coherent spatial relations at every moment. This would be to postulate a basic relationship with a temporally complex nature, for the basic relationship would have to work together with the forces described by the laws of physics as another efficient cause determining what happens. And the basic relationship would have to work together with velocity as a second efficient cause determining its future spatial relations. (This form of materialism could also use its basic relationship to explain why bits of matter change spatial relations only by motion and why they do not interact at a distance.)

Though this would allow materialists to interpret the laws of physics as descriptions of how bits of matter move and interact in space, it would be to assume that the basic relationship does for materialism what substantival space does for spatiomaterialism. The materialists' basic relationship would not be simply how bits of matter exist together at the present moment, but a way of existing together at the present moment that also constrains how they can exist together at future (or past) moments in a way that is independent of the constraints imposed by their forces and velocities. Since that is to assume that the basic relationship entails that particular spatial relations can change only in certain ways, it would be to assume that the basic relationship has a temporally complex nature.

But that makes spatial relationism more complex than spatiomaterialism. The materialists' basic relationship would be replacing both space and the basic relationship of spatiomaterialism. Though one assumption is replacing two assumptions, materialism is arguably more complex than spatiomaterialism, because its one assumption has a temporally complex nature, whereas both of the spatiomaterialists' assumptions are temporally simple. That is, aspects of regularities about change that are merely assumed by spatial relationism are explained ontologically by spatiomaterialism, including not only that bits of matter have geometrically coherent spatial relations at every moment, but that they change spatial relations only by motion and that they do not interact at a distance.

Furthermore, it might be argued that, if materialism builds these regularities about change into its basic assumption about how bits of matter exist together as a world, it is violating the spirit of ontological explanation. Ontology tries to explain basic aspects of the world by showing how they are constituted by substances that endure through time with an unchanging nature. Since the basic relationship does not endure through time on its own like a substance, but is merely how the substances exist together as a world, it cannot be a source of regularities about change in the same way as substances can. Thus, not only does spatial relationism fail to explain ontologically why bits of matter always have coherent spatial relations, it also fails to account for them in the way expected of an ontology. In short, its need to postulate a basic relationship with a temporally complex nature is itself a reason for rejecting an ontology.

Although materialism seems to be simpler than spatiomaterialism, therefore, there is, in either case, a way in which it is more complex than spatiomaterialism. Either its assumption about the essential nature of matter is more complex, or its assumption about the basic relationship by which material substances exist together as a world is more complex.

Thus, there is, at least, a standoff between spatial relationism and spatiomaterialism on grounds of simplicity. And that means that spatiomaterialism is favored by the empirical method, since spatiomaterialism has a greater scope (explaining the possibility of change by motion and by interaction).

Furthermore, the way in which spatiomaterialism is simpler than spatial relationism also a way in which it explains aspects of the world that spatial relationism can only assume. Spatiomaterialism can explain ontologically why spatial relations are always geometrically coherent (not just now, but in the future and past), whereas materialism must build that assumption either into the nature of the matter it postulates or into the nature of the basic relationship it assumes bits of matter have.

Though spatiomaterialism postulates two basic substances, rather than just one, its ontological causes are simpler than those of spatial relationism. But since both ontologies account for the same basic facts, that means that spatiomaterialism explains more with less. At the outset, we saw the greater scope of spatiomaterialism in its ontological explanation of why bits of matter have spatial relations and how change is possible (not to mention what will be show later, that they change spatial relations only by motion and do not interact at a distance). But in showing that spatiomaterialism is simpler than spatial relationism, despite initial impressions to the contrary, we have seen that its ontological causes explain another aspect of the world that materialism can only assume, namely, why bits of matter always have coherent spatial relations. In the end, therefore, it is how spatiomaterialism explain more less than makes the decision in favor of spatiomaterialism clear, at least, for naturalists who accept the empirical method.

Spatiomaterialism is better than spatiotemporalism

Substantivalism about spacetime entails, as we have seen, the perdurance theory about the temporal existential aspect of substances. But since we have already seen that the empirical method in ontology requires us to prefer the endurance theory to the perdurance theory of time, we ought to believe either spatial relationism or spatiomaterialism rather than spatiotemporalism. Both allow us to accept the endurance theory (thereby giving us an explanation of why the present is different from the past and future and allowing us to believe that change is real in the sense of properties coming into existence and going out of existence as time passes). But having established that the empirical method prefers spatiomaterialism to spatial relationism (that is, to materialism), we must conclude that spatiomaterialism is the best ontological explanation of the natural world (assuming, of course, that there is no fourth theory that is still better than spatiomaterialism).

Defenders of spatiotemporalism will, however, object to this conclusion. They believe they are forced to accept spatiotemporalism by contemporary physics. Einstein’s discovery of the special and general theories of relativity was a revolution that led to the overthrow of the Newtonian belief in absolute space and time in physics. It is clear that any ontology that holds that material substances endure through time entails that space and time are absolute. To hold that the substances constituting the world always exist at only one moment in their histories is to hold that they all exist at the same moment, for they are part of a single world and they must exist together to be parts of the same world. Thus, if there are substances with spatial relations to one another, the spatial relations they have at the present moment hold for every possible observer. This is even clearer, if space is also a substance, for in that case the spatial relations are all constituted by a substance that exists only at the present moment. Since that is to believe that space and time are absolute, to choose to believe spatiomaterialism, or for that matter spatial relationism, would be a counterrevolution in physics. Thus, it is not likely to attract many followers among physicists and philosophers of science.

What led physics to reject Newtonian absolute space and time in favor of the spacetime of Einstein’s relativity theories was the empirical method of science. Physicists were merely inferring to the best explanation of what they could observe about the world. The special and general theories both predicted quantitatively precise measurements that were not expected by classical Newtonian physics, and they have been confirmed repeatedly. Nor does anyone dispute the mathematical simplicity of Einstein’s theories. The special theory was a paragon of simplicity by comparison with the cobbling together of ad hoc constraints by which Lorentz had proposed to explain the same phenomena. The general theory of relativity was based on the special theory, and though its mathematics was novel in physics, there is no question about its elegance. These two theories were clearly the best explanation that physics offered of the space and time found in the natural world, and that caused a revolution in physics, because neither theory had any use for absolute space or absolute time. All that was required for them to be true was spacetime, that is, the ontological equality of all points in space and time.iv

The empirical method in science is, however, different from the empirical method in ontology, and thus, what is the best scientific explanation may not be the best ontological explanation. Science tries to explain what happens, and thus, it infers to the best efficient-cause explanation of what can be observed. Its criteria of truth are prediction and control. But there is, as we have seen, a difference between efficient-cause and ontological-cause explanations. Ontology tries to explain everything in the world, not only what happens there, but also what exists there — including the properties and relations of the objects found in the world, and how it is possible for anything to happen in the first place. Such things are explained ontologically by showing how they are constituted by basic substances and relations among them. Thus, empirical ontology tries to explain the world most completely using the fewest and simplest substances with the fewest and simplest relations. Though the goal of explaining the most with the least is the same, the kinds of explanation involved are different.

Since we know on empirical grounds, that spatiomaterialism is the best ontological explanation of the world, empirically minded ontological naturalists must prefer it to spatiotemporalism, if it is possible. Thus, the only relevant question is whether it is possible that spatiomaterialism is true, given that Einstein’s special and general theories of relativity are the best efficient-cause explanations of all the relevant phenomena.

The answer is Yes. It is possible to explain all the observational predictions of what will happen that is entailed by either the special or the general theory of relativity on the assumption that space is a substance enduring through time and, thus, absolute. To be sure, spatiomaterialism must make certain additional assumptions about the nature of space and matter and how they interact, which are, in effect, new laws of nature. But it is possible. (And the fact that spatiomaterialism is able to explain the truth of Einstein's two theories is further reason for preferring it over spatial relationism, because spatial relationism cannot explain them. It can only assume them in the same way it does the geometrical coherence of spatial relations.)

The spatiomaterialist interpretation of Einstein’s special and general theories of relativity is given a detailed defense below (in Change: Special theory of relativity and Change: General theory of relativity<, as one of the implications of spatiomaterialism for physics. But we can see the possibility of such an interpretation in the abstract, and since this may seem unlikely to some, let me sketch briefly just how the truth of Einsteinian relativity will be explained ontologically by spatiomaterialism.

Given the endurance theory of time, what substantivalism about space implies is that only one moment in the history of each location in absolute space exists. That is the present moment, and it is the same for all of them, since the parts of space are all parts of the same world. Thus, all that a spatiomaterialist interpretation requires is that each and every part of space (along with the bits of matter coinciding with parts of it) be in a state at the present moment that is consistent with Einstein’s two theories. What that means is that, among all the possible inertial frames, which relativity takes to be equivalent, one, and only one, is true. This is not to say that it is possible to determine by some measurement which one it is. That is clearly precluded by Einstein’s theories; if it weren't, they could not be called relativity theories. But it is equally clear that there can be an inertial frame at absolute rest, even though it is not possible to detect which one it is.

What makes such an easy accommodation possible is that empirical science and empirical ontology have different criteria of truth. Since the empirical method of science seeks the best efficient-cause explanation of what happens in the world, its criterion of truth depends on predicting and controlling what happens, and thus, given that inertial frames are all equivalent in that regard, it can take the truth to be what is the same for all of them. In ontology, however, the empirical method seeks the best ontological-cause explanation of what exists in the world. Its criterion of truth is the simplest substances and relations that will explain everything in and about the world, and thus, it must explain how all the different inertial frames could be part of the same world. That is something that science can take for granted, because one observer can always predict what coordinates will be assigned by other observers. And since the reasons for believing that there is an absolute frame of reference are ontological, the lack of any difference in the predictions made from different inertial frames is not a reason to doubt that it exists.

The detailed spatiomaterialist explanation of the two relativity theories shows, from the point of view of the inertial frame at rest in absolute space (whichever one that is), how it is possible that all the other inertial frames are observationally indistinguishable from it. Here is the gist of the explanations given in CHANGE.

The special theory of relativity implies that the various possible inertial frames (that is, the various possible unaccelerated material objects that might be used as the basis for measuring distances in space and intervals of time) are all equivalent, making it impossible ever to determine by measurement which one is at rest in absolute space. But the undetectability of absolute rest does not mean that there is no such thing. Indeed, as Lorentz began to show early in the twentieth century, it is possible to explain the observational equivalence of inertial frames which makes absolute rest undetectable on the assumption that all the material objects are located in an absolute space in which light has a constant velocity. Lorentz showed that it would not be possible to detect absolute motion by measurements of the velocity of light, if material objects with a high velocity relative to absolute space suffered several distortions (including the shrinking of their lengths in the direction of motion, the slowing down of their clocks, and increase in their mass at a certain rate). It is also possible to show that, if observers on all inertial frames accept Einstein's definition of simultaneity at a distance (and synchronize their clocks on the assumption that the velocity of light is the same both ways, back and forth, in every direction -- that is, as if they were at rest in absolute space), those same "Lorentz distortions" will make all inertial equivalent even when it comes to their measurements of one another. (Observers on both of any pair of inertial frames will see the other's clocks slowed down, the other's measuring rods as shrunken, etc.)

In other words, if we think of the effect of space on the material objects it contains as the "ether" in which Newtonian physicists thought that light had a fixed velocity (or what I will call an "inherent motion" in space), and if we assume that the motion of material objects through the ether has certain distorting effects on them and their physical processes, then all of the observational consequences of Einstein’s special theory of relativity follow. We will have explained all the phenomena without referring to spacetime. Thus, it is not necessary to give up the assumption that space is a substance enduring through time to explain what is described by Einstein's special theory of relativity.

The general theory of relativity is a theory about gravitation formulated in terms of spacetime. It holds, in effect, that matter accumulation in spacetime imposes a curvature on spacetime, and that in curved spacetime, the path of inertial motion is not straight, but curved, or in other words, accelerated. But all the predictions that follow from assuming that spacetime is curved can also be made on the assumption that the velocity of light relative to space varies from place to place in space. That is, the spatiomaterialist interpretation of Einstein’s special theory of relativity is, in effect, an ontological interpretation of what is meant by "spacetime,"and that is what makes it possible to explain the observational adequacy of Einstein’s general theory of relativity on the assumption that space is a substance enduring through time.

As suggested above, talk of "spacetime" can be replaced by talk of an ether, in which the velocity of light is equal both ways in every direction, though that is really just a way of describing how space interacts with the matter it contains. In our ontological explanation of the special theory, we assume that the ether is at rest in absolute space and we explained all the other inertial frames as observers on the one that is at absolute rest. In order to explain the general theory, we assume that the ether itself can have a velocity in space, one that varies across space according to the accumulations of matter nearby. That means that the absolute velocity of light varies from location to location in absolute space (that is, at different locations in the inertial frame at absolute rest, from which we are giving this explanation). But it also means that material objects, which interact with one another by way of electromagnetic interactions through the ether, are accelerated with the ether, and such a moving, accelerated ether is what "curved spacetime" comes down to ontologically, for as we shall see, it explains all the observational predictions of the general theory of relativity. It could all be just the effect that space has on the light and matter it contains, if the right states for space to have such effects are imposed on space by the accumulation of matter in space. Precisely the same observational predictions follow from this theory as from Einstein’s general theory of relativity, and thus, it is possible that space is a substance enduring through time, that is, absolute.

These sketches of the spatiomaterialist explanation of the truth of Einstein's two relativity theories may be too brief for most people to follow easily. But they are included here because even a suggestion of the nature of these arguments may clarify what is meant by saying that it is possible that spatiomaterialism is true, notwithstanding the Einsteinian revolution in physics. But at this point, it is still just a promise, and thus, we accept the obligation to show in detail how it is possible as we take up showing what holds necessarily, if spatiomaterialism is true. It is like taking out a mortgage in order to construct the ontological foundation for this philosophical argument. If it should turn out, as we build the edifice of ontological philosophy, that relativistic phenomena cannot be explained on the assumption that space is a substance existing in time, spatiomaterialism will have been falsified and we will not be entitled to use it as a foundation to support any conclusions about the world. We will have to concede that we do not have a new way of doing philosophy after all.

As it stands, however, spatiomaterialism is a better ontological explanation of the natural world than either spatial relationism or spatiotemporalism, because the latter two theories have opposite failings. Spatial relationism (that is, materialism) can explain why the present is different from the past and future (and, thus, can hold that change is real), but it cannot explain spatial relations. Spatiotemporalism can explain spatial relations, but it cannot explain why the present is different from the past or the future, that is, except as another kind of relation like that of space (and, thus, cannot hold that change is real). Spatiomaterialism, however, can explain both spatial relations and why the present is different from the past and the future (and, thus, can hold that change is real).

Matter

Naturalists believe that the world is just what is in space and time, and having seen that we should, if possible, believe that substances are in time in the sense of enduring through time, and that substances are in space in the sense of either being parts of space itself or coinciding with parts of space, the final issue to be settled is about the nature of the substances that coincide with space and endure through time. The simplest theory is obviously materialism, the belief that matter is the only kind of basic substance that coincides with space. But some phenomena seem to require immaterial substances as well. Our ontological causes would be more complex, if we had to postulate both material and immaterial substances as coinciding with space. But if the scope of our ontological theory is increased by postulating immaterial substances, it can be argued that there is a tradeoff between simplicity and scope that keeps the empirical method from requiring naturalists to accept materialism. In this case, therefore, we must decide whether there are any phenomena that require us to postulate immaterial substances as well as material substances. Let us set the stage by considering more carefully what materialism holds.

Materialism

Materialism holds that none but material substances coincide with parts of space. Matter comes in particular bits, and by "matter," we shall mean only substances whose behavior in space makes the laws of physics true. Thus, we assume that bits of matter move and interact in the regular ways required by the basic laws of contemporary physics and that there are enough different kinds of bits of matter to account for all the kinds of entities mentioned by those laws, from electrons and nucleons (or triplets of quarks) to force fields and photons. We will see what essential nature material substances that coincide with space must have for this to be true. (See Contingent Laws under Local Regularities under Change.) But given that it is true, materialism may also be called "physicalism," because the properties mentioned by the basic laws of physics are called "physical properties."

More abstractly, bits of matter are "basic" substances in the sense that they are the most elementary substances of their kind. Since each has an existence that is distinct from all the rest, they are "particular" substances. They are "concrete" in the sense that no bit of matter can be in two different locations at the same time. And they are "independent" of one another in the sense that the existence of one bit of matter does not, in general, depend on the existence of the others. That is, bits of matter can also move independently of one another and interact locally (though, as we shall see in Change: Forms of matter, there are some varieties of matter that cannot exist except in conjunction with matter of a different variety).

Since spatiomaterialism holds that bits of matter are in space in the sense of being contained by space as a substance, we shall take the basic laws of physics to be descriptions of regularities about their motion and interaction that result from their being contained by space, that is, as ontological effects of both space and matter. That is different from what spatial relationism assumes about the nature of matter, because spatial relationism can simply define the essential aspect of material substances by the basic laws of physics, implying that there is nothing more to be known about their natures and that bits of matter have an essential nature that is irreducibly temporally complex. But since we take space to be a substance, we are assuming that at least some of the regularities described by basic laws of physics can be explained ontologically, that is, by how the essential nature of space works together with the essential nature of matter, because of how matter and space coincide, to constitute those regularities. That is why we took spatiomaterialism to have a greater scope than spatial relationism: it could explain why bits of matter have spatial relations and how change is possible, rather than just assuming it. That is also how spatiomaterialism can promise to explain the truth of Einstein's relativity theories, as just mentioned. And it is how we will explain the other laws of physics in Contingent Laws under Change.

Indeed, the possibility of such explanations is what we assumed by taking ontology to be a kind of explanation, rather than merely realism about science. But that means that spatiomaterialism must take matter to be a kind of substance that, working together with space as the substance with which it coincides, makes the basic laws of contemporary physics true.

In addition to explaining why efficient-cause explanations are true, moreover, ontological-cause explanations can also explain why rational-cause explanations are true, making all the kinds of explanations mentioned in Method parts of a single explanation of the world in the end and reducing the social sciences by way of natural science to spatiomaterialism.

Although spatiomaterialism implies that there is more to be known about the essential nature of matter, what is relevant for present purposes is that it agrees with materialism (or physicalism) about physics being causally complete. What happens in the world is just what comes about, given the initial and boundary conditions that prevail, as the result of bits of matter moving and interacting according to the basic laws of physics. That is how all efficient causes bring about their effects, according to materialism, and spatiomaterialism expects to be able to explain why those causal connections hold. Naturalists who follow the empirical method must prefer that kind of ontology, if it is possible, because it is the simplest explanation of what happens in nature. The only question is whether it is possible.

Immaterialism

It is not possible, according to critics of materialism, because there are aspects of the natural world that require us to postulate immaterial substances in space. Though all naturalists deny the existence of anything outside space and time, all the kinds of phenomena mentioned in Naturalism: Problems as posing a problem for naturalism also pose a problem for materialism. That is, consciousness, goodness and holiness, the phenomena that lead, respectively, to the belief in Cartesian minds, Platonic Forms, and a transcendent God, can also be used to argue for the existence of substances whose natures are not described by the basic laws of physics. However, to postulate mental substances, teleological substances, or spiritual substances would be to give up materialism in favor of a more complex ontology, one with immaterial substances that coincide with space and endure through time, along with material substances.

Notice that, although space is not a material substance, it is not an immaterial substance in the sense relevant here. Space is not a material substance in the sense that it has an opposite essential nature to matter. (Whereas bits of matter are independent of one another, parts of space cannot exist without one another.) But here we are concerned with the causal completeness of physics, and by "immaterial substances," we mean only substances that coincide with space. What makes them immaterial is that they do not move and interact as described by the basic laws of physics.

Though space is not a material substance, it is not an immaterial substance in the relevant sense, because substantivalism about space does not itself deny the causal completeness of physics. On the contrary, it affords an ontological explanation of why the basic laws of physics are true and, thus, an explanation of the connection between cause and effect in efficient-cause explanations.

Ironically, however, as it will turn out, all that needs to be added to materialism in order to explain the problematic phenomena that lead to belief in immaterial substances is substantivalism about space. As we shall see, that is because it shows the ontological necessity of global regularities, as well as the local regularities described by the basic laws of physics. It order to see what spatiomaterialism must do, let us consider more carefully each of the reasons for believing in immaterial substances.

Mental substances

The first challenge to materialism comes from the existence of conscious beings like us. As explained in Naturalism: Consciousness, the basic phenomenon that leads to belief in the existence of mind is "consciousness," which will be understood here as the fact that it is like something to perceive the world and experiences of other kinds. The appearances involved in perception are something distinct from what exists in the natural world independently of us, and when we reflect on how we know about them, it seems that the appearances themselves are responsible for our being aware of them and for the judgments we make about them. That is what led Descartes to believe that minds are immaterial substances not located in space. Though we must, as naturalists, deny the existence of Cartesian minds, we must give an ontological explanation of the natural world that explains the phenomenon of consciousness.

To be conscious is to have qualia or phenomenal properties. Since they are properties of a radically different kind from the physical properties by which the essential nature of matter is defined, materialism seems to be incapable of explaining consciousness. There are several alternatives.

Eliminative materialism

What materialists can do is explain away the phenomenon. That is the position called "eliminative materialism." It assumes that everything that conscious subjects do in the world can be explained by the brain and other forms of efficient causation. That means that there is no way to show that someone else is conscious by how they behave or anything else that happens in the world. Thus, consciousness eludes the method of empirical science, since the only acceptable evidence for scientific explanations is what is known by perception. Eliminative materialism would "solve" the problem of consciousness by simply denying the existence of phenomenal properties. It holds that belief in them is the result of a confusion (see Dennett) or the lack of an adequate scientific explanation of the brain (see Churchland.)

This position is not easily refuted, since the evidence for consciousness is strictly private, in the sense that it depends on first-person reflection.

The willingness to reduce conscious subjects to what materialism can explain is, however, the sort of attitude that has given reductionistic materialism such a bad name. Most naturalists (like Chalmers) doubt that eliminative materialists are taking consciousness seriously, for naturalists are themselves parts of the natural world and they can know that they are conscious by reflection, even if natural science cannot.

Emergentism

At the other extreme is emergentism. It is possible for naturalists to give up materialism and hold that what explains this phenomenon are mental substances that coincide with space along with material substances. Emergentism is different from the belief in Cartesian minds, because it takes the mental substances to be in space, and for spatiomaterialists, to be contained by space as a substance is to coincide with some part(s) of it. But emergentism agrees with the Cartesian view about mental substances making a difference to what happens in the world. It holds that mental substances are partly responsible, at least, for behavior that is ordinarily attributed to conscious mind, such as rational behavior. Such a view, however, denies materialism, for it denies the causal completeness of physics. It implies that there are substances in space and time that do not obey the laws of physics, thereby denying that physics can, in principle, explain everything that happens in nature.v

It may seem that emergentism is not a form of immaterialism, because what emergentists mean by "conscious mind" cannot be a substance by our definition. We are assuming that substances never come into existence nor go out of existence over time, but emergentists typically hold that conscious mind comes into existence at some point because of the complexity of physical causes, for example, at some stage in the evolution of the brain. However, these views are not incompatible, because the way in which conscious mind emerges can be explained by assuming that matter itself has a (temporally complex) nature that allows its nature to change from being the kind described by the laws of physics to being a kind that gives consciousness a causal role in the world. That is to hold that there are immaterial substances in space, for it implies that there are substances that do not obey the basic laws of physics. That may mean that there are no material substances, only immaterial substances that appear at times to be material. In any case, it is a naturalistic theory. But since bits of matter would have to follow more complex laws than those of physics, the existence of emergent minds would require a more complex ontology, and thus, naturalists have good reason to prefer a less disruptive explanation of consciousness, if it is possible.

Epiphenomenalism

Epiphenomenalism is a compromise between eliminative materialism and emergentism. It holds that all the causal roles of conscious mind are really the work of the brain and, thus, can ultimately be explained by matter alone. Thus, it cleaves to materialism and believes in the causal completeness of physics. But it also holds that processes involving physical properties of those kinds "give rise" to phenomenal properties. That is how it explains the phenomenon of consciousness. Since those phenomenal properties have no effects, in turn, on what happens in the world, it is called "epi-phenomenalism." That is, phenomenal properties are effects of physical properties without ever themselves being causes of anything. Such a view avoids postulating any immaterial substances, since the substances in space would always obey the laws of physical. But it would have to assume that material substances can have properties that are not mentioned by the basic laws of physics. Thus, it accepts what is called "property dualism," while cleaving to materialism (or physicalism). Matter must have phenomenal properties as well as physical properties.

Epiphenomenalism is, however, an unhappy compromise, because phenomenal properties are fundamentally different from the properties by which materialists define the essential natures of material substances. They are not entailed by anything that physics can discover about the world. Thus, it is possible to conceive of a physical world in which organisms with brains exactly like our own did not have phenomenal properties. That is, there may be zombies. Or to use Kripke’s famous metaphor, epiphenomenalism makes it seem as though, God, after creating the physical world, had to go back and tack phenomenal properties onto material substances in order to make beings like us conscious. Thus, even though epiphenomenalism allows naturalists to avoid immaterialism, there is still reason to believe that materialism is not the deepest truth about the nature of existence in the natural world, because consciousness is still something found in the world that does not seem to be constituted by material substances.

In order to be the best ontological explanation of the natural world, therefore, spatiomaterialism must explain consciousness. That is, it must explain the relationship between physical and phenomenal properties in a way that shows phenomenological properties to be ontologically necessary.

And it can. Indeed, that will be the first necessary truth derived from this ontological foundation. (See Properties.)

However, since this is only a promise at this point, we are taking out a second mortgage on the house of ontological philosophy in order to construct its foundation (that is, in addition to explaining why Einsteinian relativity is true), and only if we pay off both mortgages will we have a clear title to a new way of doing philosophy. But as it now stands, if we do pay them back, the empirical method will require us to accept spatiomaterialism as true, and we will not be able to deny the necessary truths that follow from it. This argument will be a new way of doing philosophy.

Teleological substances

Another problem with naturalism is the existence of a real difference between good and bad, that is, a difference in the objects or events themselves that make it true that some ought to exist and others ought not. That is the phenomenon that led Plato to believe in the existence of Forms in a realm of Being, and the same phenomenon that theists believed they could explain by the existence of a God who created the natural world. Though as naturalists, we must deny both of those supernaturalistic explanations, we do need an explanation of the phenomenon itself. If it cannot be explained by materialism, goodness will count as evidence for the existence of immaterial substances.

Hedonism

The time-honored way for materialists to explain the phenomenon of goodness is by offering a causal explanation of what is good, such as psychological hedonism, that is, the view that beings like us cannot help but seek pleasure. But that is to hold, in effect, that pleasure is what is good without explaining why the good is good in the sense that it ought to exist. It would only explain why hedonistic beings like us inevitably pursue it.

Furthermore, hedonism does not explain moral goodness, for it does not explain why we ought to do what morality requires when it does not maximize our expected pleasure, that is, when it is not in our self-interest.

Nor is the goodness of morality explained by theories, like Hume's, that take human nature to include a moral sentiment, which inclines one to do what is moral when it conflicts with self interest. Such a psychological disposition may explain why human beings are moral, but not why they ought to be.

Non-cognitivism

The other traditional naturalistic attempt to explain the phenomenon of goodness is to hold that it is an illusion. The appearance that there is an objective difference between good and bad could comes from projecting our feelings about things onto the world, so that they appear to be properties of the objects themselves. This view has had many defenders in the Twentieth Century (such as Ayer).

These ways of answering the challenge of goodness are, once again, what has given materialist reductionism a bad name. They do not convince everyone, and those who continue to believe in a real difference between good and bad, in which the good really ought to exist regardless what we may happen to (or be determined to) believe about it, will accuse materialists of leaving something out of their supposedly complete explanation of the world. Thus, although materialism is the simplest ontological explanation of the natural world, the empirical method cannot force us to accept it as true as long it cannot explain goodness as something that beings like us find in the natural world.

In order to explain the phenomenon of goodness, it may be argued that naturalists must postulate teleological substances of some kind, such as Aristotle did by holding that there are final causes as well as efficient causes at work in nature. To suppose that forces of any kind are responsible for the goals pursued by biological organisms generally or by human beings would be to hold that there are substances that somehow guide change in nature to bring about certain states or goals. They could not be material substances, because substances whose essential natures are described by the basic laws of physics do not have such forward-looking effects (unless, of course, they have very special initial and boundary conditions as parts of mechanisms, which would need to be explained). In order to account for final causation, for example, Aristotle postulated essential forms as a component of each particular substance in space. Indeed, the actualization of the essential form that exists potentially in substances of its natural kind was supposed to be the end for the sake of which "natural change" takes place.

Nor was it just their role in final causation that made them immaterial substances. Though essential forms are located in space and time as a component, along with matter, of the particular substances that have them, the same essential form must be able to exist simultaneously in different particular substances with different locations in space at the same time. Thus, they are universals, not concrete material substances.

It may be possible to materialize teleological causation (as " vitalists" like Hans Driesch did) by postulating "entelechies" (instead of essential forms and final causes) and holding that each entelechy can exist at only one location in space at a time. But still, any substances exerting teleological forces would be unlike the substances that materialists accept, because in order to guide motion and interaction toward certain goals, they would have to work in more complex ways than provided by the basic laws of physics. And even if they did, making what is good objective, it would still be necessary to show how that explains why the goals pursued are good.

The defense of teleological substances has been rare ever since the discovery earlier in this century that Darwin was on the right track in explaining natural teleology as a result of evolution. Darwin showed how the natural selection of random variations in reproducing organisms could explain why change seems to occur for the sake of ends in them. The existence of traits serving specific functions was a result of the differential survival and reproduction of organisms having the traits, while other organisms, lacking the traits, died out. In other words, it is merely an adaptation to the environment. And when the role of genes in the inheritance of traits became clear, it was even harder to believe that immaterial substances were responsible for the goal-directed traits of biological organisms -- and harder still when DNA molecules were found to be playing the role of genes. Since nothing but efficient causes are involved in the mechanism of inheritance and their evolution by natural selection, it was no longer plausible to believe in the existence of teleological substances.

This evolutionary explanation of the goal-directedness of biological traits is not, however, an explanation of the phenomenon of goodness. The consensus among contemporary Darwinists is that Darwin’s theory has nothing to do with progressive evolution. As we mentioned earlier, they believe that the cause of natural selection is externally caused changes in the environment, which makes the course of evolution seem accidental. What is more, since organisms must make do with whatever random variations turn up when the environment changes, it also suggests that evolved traits are not generally the best way to serve the functions required, but merely what enabled them to survive difficult periods. (For a fuller discussion of contemporary Darwinism, see Change: Accidentalism.) Thus, to those who believe that there is a real difference between good and bad, one that explains why the good ought to exist, the contemporary Darwinist explanation of the ends pursued by organisms seems more like an attempt to debunk their belief in goodness than an explanation of its nature.

Goodness remains, therefore, a source of doubt about materialism. Though materialism may be part of the simplest explanation of the natural world, there will be naturalists who do not accept it, as long as it cannot explain why things are good in the sense that they ought to exist. They have reason to believe that teleological substances of some kind are required to explain this phenomena. The tradeoff between simplicity and scope prevents the empirical method from deciding.

In order to hold that the empirical method requires naturalists to believe that materialism is true, therefore, and that there are no immaterial substances in space, it will be necessary to explain the phenomenon of goodness to the satisfaction of those who believe in an objective difference between good and bad. That is, it will be necessary to give an explanation of the goals pursued by beings like us (and by other organisms) that explains why those goals ought to be pursued.

In order to establish this foundation for ontological philosophy, therefore, we must take out a third mortgage on the necessary truths supported by it. Not only must spatiomaterialism explain the truth of Einstein's two relativity theories and the nature of consciousness, but it must also explain the nature of goodness. And if it turns out that we cannot pay off these mortgages, it will not be clear that spatiomaterialism is the best ontological explanation of the natural world. We will not be entitled to claim that any truths founded on its are necessary relative to what is ordinarily believed.

It will, however, turn out that spatiomaterialism can pay off this mortgage. There is a better explanation of the difference between good and bad than contemporary Darwinists offer, and ironically, what makes it possible is the recognition that space is a substance. The key, once again, is how substantivalism about space entails the ontological necessity of global regularities, for evolution is the "Reproductive Global Regularity

Spiritual substances

The final reason for doubting that materialism (or we are assuming, spatiomaterialism) is the best ontological explanation of the natural world is what we called the phenomenon of "holiness," which leads people to believe in the existence of a transcendent God. Though, as naturalists, we must deny the existence of a transcendent God, the phenomenon that gives rise to belief in God calls for explanation, and if we cannot explain why people believe that is something worthy of worship without postulating spiritual or other immaterial substances in space, the empirical method will not force naturalists to accept spatiomaterialism. There will again be a tradeoff between simplicity and greater scope that makes it unclear whether spatiomaterialism or some from of immaterialism is the better ontological of the natural world.

In this case, once again, a common materialist response to the challenge is to hold that what needs explaining is not the phenomenon of holiness, but rather the belief in God itself. Thus, people are said to have a psychological need to believe in God, either as a result of conditioning (behaviorism), psycho-sexual development (Freudianism), an instinct selected for other functions (sociobiology), or some other irrational cause. This is materialist reductionism in the pejorative sense. It does not take seriously the source of the belief in the sacred, at least, not in the eyes of those who believe there is something worthy of worship.

This sort of explanation is not required by naturalism, that is, the denial of supernaturalism, for religious people can be naturalists. Though naturalists cannot believe in the existence of a transcendent God of any kind, they can insist that there is something immaterial in the natural world that is worthy of worship. It is not obvious, after all, that what is holy must exist outside space and time. It could be a spiritual substance in space, if not the world itself.

The existence of spiritual substances is not, however, compatible with materialism. A spiritual substance must have effects that are different from what happens as bits of matter move and interact according to the basic laws of physics, for otherwise there would be no reason to believe that a spiritual substance exists, much less that it is worthy of worship. Thus, it must not be a material substance in our sense.

Nor is it sufficient to declare that the world itself is worthy of worship. There must be something about the world that makes it holy, and naturalists have never explained what it is.

Spinoza's pantheism was rejected by traditional theists for this reason. His metaphysics explained why goals are pursued by beings in the world, but it denied that pursuing them was a result of free will and it failed to explain why those goals are good.

It may not seem necessary, in the case of holiness, to take out a fourth mortgage to establish spatiomaterialism as the foundation for a new way of doing philosophy, because if spatiomaterialism can explain everything but how there is something worthy of worship in the natural world, it could be argued that what we have discovered is that there is nothing sacred in space.

However, that would not work, if there were naturalists who continued to believe in the sacred, because they would insist that it can be explained by some kind of immaterialism. And if they were not just being willful or arbitrary, but argued with us, giving reasons for believing in spiritual substances of some kind, we could not claim that the empirical method forces naturalists to believe that spatiomaterialism is true. There would be a tradeoff between the simplicity of materialism and the scope of immaterialism, and we could not, in good conscience, defend any of the necessary truths of ontological philosophy.

Thus, we will take out a fourth mortgage on the foundation needed to do philosophy in this new way. It may seem wildly optimistic at this point, or even foolish, to promise an explanation of holiness. But as we shall see, spatiomaterialism does show that there is something in or about the natural world that is worthy of worship. This fourth mortgage will be paid back in the sense that either the religiously inclined will agree that it explains what they are getting at, or else we will have sufficient grounds for holding that they are not being fully rational about all the relevant issues in rejecting it. The dispute may continue at that point, but it will be about their rationality, not about whether spatiomaterialism is the foundation for a new way of doing philosophy.

This completes the construction of the foundation of ontological philosophy, though we carry quite a burden with us as we take up the project of using spatiomaterialism as a foundation for necessary truths. In order to hold that spatiomaterialism is the best ontological explanation of the natural world, we must explain why Einsteinian relativity is true, why beings like us are conscious, how there is a real difference between good and bad, and how there is something in the natural world that is worthy of worship. If we can pay off those mortgages, however, the edifice that we shall construct on that foundation will stand. What spatiomaterialism implies about the world will hold necessarily relative to science and our ordinary ways of reasoning about what to believe, including empirical science, ethics, and the whole gamut of ordinary cognitive endeavors. And the use of an empirical naturalistic ontology as a foundation for necessary truths will have proved itself to be a new way of doing philosophy.

Necessary Truths of Ontological Philosophy

Having now established spatiomaterialism as the foundation for ontological philosophy, it remains to discover the necessary truths that follow from it. The new necessary truths follow mainly from the recognition that space is an ontological cause of the natural world, for that entails the ontological necessity of several global regularities (at least in spatiomaterial worlds where the laws of physics are true), including evolutionary change. Those global regularities are one manifestation of the wholeness of the world. But we are at a major juncture in this philosophical argument, and it may help keep issues clear to step back and recall what philosophy is that ontological philosophy can claim to be a new way of doing philosophy. And see how an empirical foundation can yield truths of any kind, necessary or not, that have not already been discovered by modern science.

Nature of philosophy

Philosophy aspires to a more fundamental kind of knowledge about the world than is provided by ordinary ways of knowing (such as modern science and everyday practical reasoning). Any such superior knowledge would require a special foundation. Hence, philosophy is a two-step argument. First, it establishes its foundation, and, second, it uses its foundation to demonstrate necessary truths. Necessary truths are prior to what is known by ordinary means, because what is demonstrated from its foundation cannot be denied without giving up the philosophical foundation.

Epistemological philosophy

That is, at least, the structure of traditional philosophy. Though different foundations were used in different eras of philosophy, they were always epistemological. Traditional philosophy always used reflection on how beings like us know in order to establish some theory about the nature of reason (such as the intuition of forms, certainty about ideas in the mind, and the language-users’ understanding of language). The fruit of such theories was borne in the second step, when the foundations were used to show that certain propositions about the world hold necessarily. Those implications had an authority that was superior to ordinary ways of knowing, for they could be denied only by giving up the theory about the nature of reason. In other words, the necessity of the propositions defended by traditional philosophy was epistemological. Insofar as they were successful, what they showed was that certain propositions are certain.

It is now generally recognized in intellectual circles that traditional philosophy failed to make good on those claims. Indeed, its failure seems so obvious that philosophy itself now seems to be a bad idea. "Foundationalism," as it is called, is not merely eschewed by most contemporary philosophers. It is often cited as something so misguided that it is supposed to be a wonder anyone ever believed in it. The failure of foundationalism is the main support for relativism, and since the most common defense against the charge of relativism attempts to undercut it by denying that philosophy was plausible in the first place, both sides see traditional philosophy as childish. But it is not necessary to renounce philosophy entirely in order to avoid relativism, because there is another way of doing it.

Ontological philosophy

Another way of doing philosophy is possible, because epistemology is not the only foundation from which necessary truths can be demonstrated. It is also possible to use ontology as a philosophical foundation. Philosophical arguments of all kinds start from our ordinary knowledge about the world, in which we recognize that we all have bodies alongside one another and other objects in space. But instead of establishing a foundation for philosophy by using reflection on how we know to justify some theory about the nature of reason, it is possible to establish a philosophical foundation by using perception to justify some theory about the natures of the basic substances and relationships that constitute everything in the world. This is to move in the opposite direction from epistemological philosophy: deeper into the natural world, rather than stepping back and reflecting on how we know about it. But the role of perception means that ontological philosophy must rely on the empirical method to determine which specific ontological theory to accept; it must infer to fewest and simplest basic substances and basic relationship that can explain every aspect of the world. Then, in the second step, what follows from that ontology are the necessary truths of ontological philosophy. What is implied by the ontology has a claim on our credence that is superior to ordinary knowledge, because it can be denied only by giving up the best ontological explanation of the most basic aspects of the natural world. Those implications are, therefore, ontologically necessary. They are not, however, certain, because their ontological foundation can be falsified by experience.

It may be surprising that there is a new foundation for philosophy to use, especially one established by the empirical method, for that is the method of science. But we have seen what makes it possible. It comes from recognizing that ontology itself can be explanatory, for that makes ontology different from scientific realism. Ontological-cause explanations are different from efficient-cause explanations. Indeed, they are prior to efficient-cause explanations, because ontological explanations can explain why efficient-cause explanations are true, but not vise versa. Thus, it is possible to use the empirical method and infer to the best ontological explanation of what exists in the world before we infer to the best efficient-cause explanation of what happens there. That makes it possible to have a foundation for ontological philosophy that is different from scientific realism, or what scientists must believe about substances in order to accept the truth of their theories about efficient causes.

How an empirical philosophical foundation is possible

Even those who recognize that it is possible, in principle, to found a new way of doing philosophy on empirical ontology may find it surprising that any empirically justified foundation could support new truths about the world. If they depend ultimately on perception of the natural world, they must surely have already been discovered by empirical science.

But we have already seen how empirical ontology can provide a philosophical foundation that is different from empirical science. It comes from the difference between the best ontological explanation of the natural world and the ontological beliefs to which empirical scientists (and philosophers of science) are actually committed by the efficient-cause explanations they accept, that is, as scientific realists. In particular, physics does not recognize that space is a substance. Physics infers only to the best efficient-cause explanation of what is observed in nature, and since the relevant observations involve precise measurements, it tries to find the mathematically simplest laws of nature that can predict the entire range of relevant measurements. Those laws do not mention space or time except to describe the spatial and temporal relations among particular events that are observed, and so when scientific realists use physics to determine what exists in the world, they fail to recognize that space is a substance.

There are, as we have seen, two popular ontologies defended through realism about contemporary physics: materialism and substantivalism about spacetime (or what I called spatial relationism and spatiotemporalism). Neither recognizes that space is a substance. Materialism reduces space to spatial relationism, and while spatiotemporalism recognizes that spatial relations are constituted by something that exists independently of matter, it denies the reality of absolute space in favor of spacetime. Thus, it is not so surprising, after all, that an empirical naturalistic ontology can demonstrate necessary truths that are not currently recognized.

By the same token, however, this difference between ontological philosophy and contemporary physics can be seen as a reason for doubting that spatiomaterialism is true. That is what forced us to take out a mortgage on spatiomaterialism in order to use it as the ontological foundation of our philosophical argument. We had to promise to show how it is possible for spatiomaterialism to explain the truth of Einsteinian physics, acknowledging that we will forfeit our foundation if we fail to do so. Such an explanation is given below (Contemporary Physics under Change).

The possibility of spatiomaterialism despite Einsteinian physics will be shown by making further assumptions about the essential natures of space and matter and showing how substances of those more specific kinds would constitute a world in which Einstein’s special and general theories of relativity make true predictions of what happens. This is not to give up the assumption that space, like matter, endures through time, even though that implies that space and time are absolute. On the contrary, it is by retaining our basic assumptions about space and matter that we show that it is possible for spatiomaterialism to be true of a world in which Einstein’s theories have been confirmed. But this demonstration of the possibility of spatiomaterialism will leave us with a more detailed conception of the nature of space and matter.

In a similar way, the truth of the other basic theories of physics, including quantum mechanics and what I currently holds about the basic particles, will be explained ontologically. That will require the assumption of still more detailed essential natures for both space and matter.

In order to be clear about the nature of the second step of ontological philosophy, however, we should recognize that this ontological explanation of the truth of contemporary physics is not a demonstration of ontologically necessary truths. It is, rather, part of the project of empirical ontology itself, that is, the attempt to infer to the best ontological explanation of the world. And since it goes beyond the general kind of spatiomaterialism that was established as the foundation of ontological philosophy, it is the job of empirical ontology as a more basic branch of science than physics.

The kind of spatiomaterialism that has been established as the foundation for ontological philosophy is quite abstract and general in its requirements. Space and matter are assumed to have opposite kinds of essential natures as substances in the sense that bits of matter can exist independently of one another whereas parts of space have spatial relations to one another as part of their essential nature. Their opposite natures explain how these two kinds of basic substances can exist together as a single world. Each bit of matter coincides with some part of space or other at each moment as both matter and space endure through time. These are the assumptions from which the ontologically necessary truths follow.

But that is not all there is to the essential natures of mater and space, for bits of matter also exhibit various more specific regularities about how they move and interact. Such regularities are described by the basic laws of physics, and if those more specific aspects of the behavior of bits of matter in space are to be explained ontologically, it will be necessary to make more specific assumptions about the nature of matter. That is how we will show the compatibility of spatiomaterialism with Einstein’s relativity theories: there are certain further assumptions about the natures of space and matter that would account for all the observation on which Einstein’s theories are based empirically. Likewise for all the other theories of contemporary physics.

Empirical ontology infers to the best ontological explanation of what is found in the natural world, and since what is found in nature include the regularities described by the basic laws of physics, it includes discovering the natures of the two basic substances that explains them best. But that is the project of empirical ontology as the most basic branch of science, prior to physics, and it is not quite what is offered in the following sections. The argument about physics in the following sections is only an initial contribution to that project. Since what is relevant for ontological philosophy is showing the possibility of spatiomaterialism, it is not necessary to identify the best spatiomaterialist explanation of why the basic laws of physics are true. It is only necessary to show that there is some more specific spatiomaterialist ontology that can explain their truth. Thus, what is offered below is not necessarily the simplest or most complete explanation of physical laws. The formulation of that ontological theory is left to be completed as part of ontological science. The ontological explanation offered here is meant only to show how such an explanation is possible within the constraint of spatiomaterialism.

Nature of Ontologically Necessary Truth

What follows from the ontology established as a philosophical foundation is necessarily true. In order to be clear about what that means, let me say something more about the nature of truth and necessity.

The Nature of Truth

We assume that propositions are true when they correspond to what exists. That is to accept the correspondence theory of truth, and that should not be problematic, because it is what is ordinarily assumed about truth. It is part of the natural attitude from which philosophical arguments of all kinds begin. Both the ontological theory itself and the necessary truths that follow from it are true in the sense of corresponding to the world, if they are true at all.

Even though we used the empirical method to choose which ontological theory to believe, to believe the theory is to believe that it is true, and thus, since we accept the correspondence theory of truth, we take that to mean that spatiomaterialism corresponds to what exists. The world is actually constituted by space and matter as substances enduring through time. As a theory in ontology, however, it corresponds to the most basic aspects of the world, which include not only the essential natures of the basic substances and their basic relationship, but also the nature of substance as substance (both existential and essential aspects) -- and even the fact that the world is constituted by basic substances that exist together as a world in a basic way.

What follows logically from the ontological theory that best explains the world ontologically is also true in the sense of corresponding to what exists. But our reason for believing they are true is different, because they must be true, if the ontological theory form which they follow is true, and we have other reasons for believing that the ontological theory is true. Given the truth of the ontological theory, what follows from it must be true, and that logical entailment is one sense in which they are necessary truth. But it is not all that is meant by saying that they are ontologically necessary.

The Nature of Ontological Necessity

In order for propositions to be ontologically necessary, they must follow logically from the ontological theory established in the foundation. But ontological necessity is more than mere logical necessity. What makes them ontologically necessary is that the premises from which they follow logically is the ontological theory that offers the best ontological explanation of what is found in the world. That is, what follows from the ontology inherits its authority, and that gives those implications a special claim to credence when it comes to settling issues that arise from our ordinary ways of knowing. It is a more fundamental truth about the world and deserves special respect relative to what is known by ordinary means.

Though ontologically necessary truths cannot directly contradict what is observed (since that would falsify the ontological theory from which they follow), they can settle issues that arise in ordinary ways of knowing. For example, when there is a dispute about what caused some particular event in the world and one of the alternative explanations is contrary to what is necessarily true, there is good reason to dismiss it in favor of the other alternatives. To insist that that alternative is possible would be to give up the best ontological explanation of the world.

The difference between ontological and mere logical necessity can, perhaps, be elucidated by suggesting that ontological philosophy is an explanation of why its implications are true. The premise from which ontologically necessary truths follow is an ontological theory, which describes the most basic aspects of the world, and thus, formal derivations from it involve the construction of further aspects of the world, showing either that they are possible or impossible. That is the content or meaning of the derivation, and since these aspects are fundamental, they can be seen as permitting some beliefs about the world because they could correspond to what exists in the world or as prohibiting them because they would not.

For example, since each bit of matter is assumed to coincide with some part of space or another, spatiomaterialism implies that bits of matter have spatial relations to one another that all fit together as a three-dimensional geometrical whole. Thus, observations of spatial relations that seem to contradict geometry should be doubted, because they cannot correspond to anything in a spatiomaterial world. And since space and time are both continuous, change is possible, for bits of matter can move from one part of space to another without changing their natures or basic relationship. Thus, we should expect reports of objects moving, because there can be aspects of a spatiomaterial world to which they correspond. But that explanation of the possibility of motion also implies that it is not possible for bits of matter to change their location in space without moving across space between their origin and destination. Thus, one should doubt reports of objects flitting about in space discontinuously because there is no aspect to which they can correspond in a spatiomaterial world.

We can understand formal derivations from spatiomaterialism as the construction of aspects of the world from ontological causes because we have, in addition to the use of language, a faculty of spatial imagination. Both these cognitive powers will be explained later as essential traits of rational beings (when we see why rational beings are necessary beings in a spatiomaterial world like ours). We do not, of course, need to understand how we are able to understand this argument in order to understand it. But it may help clarify how this argument for necessary truths is intended, if I make clear that I am assuming that we are able to think about the spatial aspects of the world in a non-linguistic way. This is what is involved in understanding ontological explanations as something more than the formal relationship that holds between the ontological theory itself and the propositions it implies.

The correspondence that makes the ontological theory and its implications true is, therefore, one that involves spatial imagination as well as the formal linguistic structure of the propositions: the images in spatial imagination must correspond to aspects of the world in order for the sentences whose meanings they are to correspond to them. That warning may help avoid confusion about the way in which the correspondence of sentences to the world will be explained, when we finally get around to explaining the nature of reason ontologically.

Ontologically necessary truths can be interpreted, therefore, as truths that hold in every possible world. In this case, the ontologically necessary truths are truths that hold in any possible spatiomaterial world. Spatial imagination enables us to survey the range of possible spatiomaterial worlds. That range is still rather broad, since spatiomaterialism is still a rather general and abstract about the nature of the world. Accordingly, the necessary truths that follow from it without further assumptions are not very exacting. They include the fact that bits of matter all have geometrically coherent spatial relations, that their spatial relations can change, that they can change only by motion, and a similar set of principles about interactions. But otherwise they are not very specific about how and why spatial relations change.

Conditional ontologically necessary truths

There is, however, an important distinction among ontologically necessary truth which arises from the ontological explanation of the truth of the laws of physics. Such an explanation of Einstein’s two theories of relativity is required in order to show that spatiomaterialism is possible and thereby repay one of the mortgages we took out in order to use spatiomaterialism as a foundation for doing philosophy. But the assumption that space and matter have essential natures of a kind that makes the basic laws of physics true will play an additional role in this philosophical argument. Together with the recognition that space is a substance, these more specific assumptions about the natures of matter and space give us such a complete representation of the essential nature of the world that we will be able to derive many additional profound and far reaching conclusions about the world. As we shall see, the assumption that space is a substance combines with the laws of physics to show that various regularities hold of whole, relatively isolated regions of space, and it is only because those “global regularities” include evolutionary change that spatiomaterialism is able to explain the phenomena that have raised doubts about materialism and seemed to lie beyond the limits of science. The nature of evolutionary change entails that certain kinds of organisms have essential natures, including rational beings like us, and if rational beings were not necessary beings, it would not be possible to explain consciousness, goodness, and how there can be something worthy of worship, or holiness, in a strictly natural world.

In other words, we shall need to assume that the laws of physics are true in order to pay off the other three mortgages that we have taken out in order to use spatiomaterialism as the foundation for our philosophical argument. Though the basic nature of consciousness depends only on the most basic ontological assumptions, both substantivalism about space and the truth of the laws of physics are required in order to show the ontological necessity of the rational beings who are conscious. And it is that evolutionary explanation of such rational beings that entails that there is a real difference between good and bad for them and that there is something in the world that is worthy of their worship.

These implications are also ontologically necessary, because they cannot be denied without giving up the best ontological explanation of the natural world. But since the ontology from which they follow is spatiomaterialism of a kind that can explain the truth of physics, they will be said to be “conditionally ontologically necessary truths.” The condition on which their ontologically necessary truth depends is that the basic laws of physics are true. If those laws should turn out to be mistaken, then the necessary truths demonstrated from our ontology may not be true either. In other words, most of the propositions derived in the second step of ontological philosophy are ontologically necessary only in spatiomaterial worlds like ours, where the laws of physics are true. Or in terms of possible worlds, most of the necessary truths demonstrated by ontological philosophy hold, not of every possible spatiomaterial world, but only of every possible spatiomaterial world like ours.

Survey of necessary truths

The necessary truths that hold in a spatiomaterial world like ours are represented in the Whole Diagram as following from the foundation. Some of the necessary truths are new in the sense that they were not previously recognized as true at all, and others are new merely in the sense that they have not previously been demonstrated to be necessary (though some have long been assumed to be certain or necessary in some sense).

There are two kinds of necessary truths, truths about What Is, and truths about What Ought To Be, or succinctly, about the true and the good. Moreover, these implications for science and ethics fall out in a certain order. What is good depends on what is true (as indicated by the horizontal arrow in the diagram of the whole argument between "What Is" and "What Ought To Be"). Likewise, within the true, what is necessary about science depends on what is necessary about relations, just as what is necessary about relations depends on what is necessary about properties. And within the good, what is morally good depends on what is naturally good, and what is absolutely good depends on what is morally good. (These dependencies are also represented by horizontal arrows.)

Since the ontologically necessary truths about what is entail both the nature and existence of rational beings like us in a spatiomaterial world like ours, and since it turns out that rational beings inevitably come to understand their world ontologically, there is a green oval toward the bottom of the Whole Diagram which represents reason's coming to know what can be known by reason in a spatiomaterial world like ours.

What is

The whole diagram represents the structure of the argument of ontological philosophy. It has a place for everything that reason can know, including not only what is necessarily true, but also what is contingently true. Necessary truths provide the structure in which the actual is contained as one of the range of possibilities. While necessary truths are known to be true by deriving them from the best ontological explanation of the world, contingent truths require further experience of what actually happens in the world.

The distinction between truths about "what is" and "what ought to be" mirrors the two main functions of reason. Reason is both theoretical and practical, because rational beings need to know not only what to believe, but also what to do. In both cases, beliefs are true because they correspond to what exists. Truths are ontologically necessary when they correspond to what exists in all possible spatiomaterial worlds, though most of the necessary truths (of both theoretical and practical reason) derived in the following sections are only conditionally ontologically necessary. They hold only in every possible spatiomaterial world like ours, for they also depend on space and matter having the specific kind of nature they have in our world (that is, where the laws of physics are true).

Necessary truths about what is follow from the spatiomaterialist explanation of how space and matter constitute properties, relations and change:

Explaining the nature of properties ontologically solves the so-called “hard problem” about the nature of consciousness, for it explains why there are phenomenal properties as well as physical properties. (If properties are aspects of substances, then bits of matter must have intrinsic properties as well as extrinsic properties.)

The spatiomaterialist explanation of the nature of relations shows how mathematics is true, why math is ontologically necessary, and what makes it seem to be certain. (Recognizing space as a substance makes it possible to explain all the ways in which set theory can be interpreted, showing how they are all true.)

Its explanation of the nature of change solves Hume’s problem of induction by explaining change as an aspect of substances enduring through time. Since space is recognized as one of the basic substances enduring through time, that enables spatiomaterialism to show that certain “global regularities” hold necessarily. Those regularities include the conservation of matter, the second law of thermodynamics, the principles of mechanics, and evolutionary change.

Space causes evolutionary change in two ways, implying that that the overall course of evolution is an inevitable series of stages at each of which there is gradual change in the direction of maximum power.

At each stage, space causes some kind of (biological) machine to gradually become as powerful as possible in controlling conditions affecting its reproduction both individually and collectively. This is because those machines are not only able to control relevant conditions, but also reproduce. They inevitably impose natural selection on themselves by their own population growth. Since space is what makes cycles of reproduction add up to scarcity over time, space is an ontological cause of natural selection, helping to make it inevitable in a spatiomaterial world like ours.

Space is also what enables one stage to lead to another, because, once biological machines approach maximum power for their kind, they can be organized as so many different parts of a more complex biological machine. Their reproduction as a whole then causes them to become maximally powerful in the same way, that is, by natural selection. Space causes new stages of evolution, because space is what makes such higher levels of part-whole complexity possible.

Because evolution is an ontologically necessary global regularity in a spatiomaterial world like ours, the organisms that evolve at each stage are natural kinds with essential natures. Rational beings are the organisms that evolve at one of those stages, implying that we are necessary beings in a spatiomaterial world like ours. And given how the series of evolutionary stages leading up to rational beings like us is explained, spatiomaterialism even entails a theory about how the brain works, solving problems of neurophysiology. Thus, ontological philosophy explains the nature of mind (including consciousness), imagination, language, reason and even spirit.

Necessary truths about what ought to be also follow from the spatiomaterialist ontological explanation of the nature of evolutionary change. In a spatiomaterial world like ours, matter and space constitute rational beings with an individual self interest, a moral interest (deriving from their spiritual self interest), and a religious (self) interest. Besides showing what is good for rational beings, ontological philosophy explains why the good is good for rational beings, so that it compels rational beings choose what is good because it is good. In the end, that means that rational beings will recognize that they ought to do what is good for the world as a whole. That is the religious interest that they will come to recognize themselves as having.

Properties

Among the necessary truths about what is that follow from spatiomaterialism, the first set has to do with the nature of properties. Its main significance for issues in traditional philosophy is how it offers naturalists a solution to the problem of mind. By "consciousness," I mean the the fact that experience has an appearance to the subject, or that it is like something to be the subject. It cannot be explained without substances having phenomenal properties as well as physical properties, and ontological philosophy offers an explanation of phenomenal properties which entails that they have a necessary relationship to physical properties.

This implication of our ontology does not depend on recognizing the existence of space, but would follow from any form of materialism that took ontology to be explanatory and used the concept of substance introduced in Ontology: Substances. That makes it unique among the implications of ontological philosophy concerning the issues raised by traditional philosophical issues, for the rest depend on substantivalism about space.

In the case of phenomenal properties, the implications depend on our definition of the nature of substance, and the reason contemporary naturalists have overlooked this explanation is that materialism (or physicalism) is understood as realism about the theories of contemporary physics. Materialists posit the existence of whatever is required for the truth of the theories they believe, but they do not think much further about the nature of substances and properties. Thus, they take properties to be as ontologically basic as material substances, and that makes the relationship between physical and phenomenal properties seem puzzling.

Let us consider first what ontological philosophy implies about the nature of basic properties and their kinds before we take up the problem that follow from taking properties as just objects of knowledge.

Properties as aspects of substances. We have already seen how properties are related to the substances postulated by an explanatory ontology. They are aspects of substances, or part of what is assumed by postulating them which reason can pick out. We leave open questions about how rational beings like us are able to distinguish one aspect from another (until we discuss how reason comes to exist in a spatiomaterialist world like ours and see how reason depends on spatial imagination).

The basic properties of substances.We have already seen that substances, as substances, have two basic aspects, existence and essence. That is, they have the property of existence as well as an essential aspect to their nature. (See Ontology: Nature of substance.) But at this point, we must recognize two further aspects that may be involved in the essential aspect of the nature of substance as substance.

Existence. We have already seen how the existential aspect of substance as substance (or its property of existing) includes two properties, particularity and temporality. In other words, to say that a substance exists is to say that it has an existence that is distinct from other substances in the world (particularity) and that it endures through time temporality). (We take the temporal aspect to be endurance, because we have seen that endurance is the best ontological explanation of the nature of time, including both change and what makes the present different from past and future than perdurance. See Spatiomaterialism: Best explanation of time.)

Essence. Each substance must have an essential aspect in addition to its existential aspect, because in order to exist at all, it must exist in some determinate way. This was our reason for holding that substances have two basic aspects to their natures as substances, not only existence, but also an essence. It makes no sense to hold that something exists and to deny that it has any further aspect to its nature. But there may be two aspects to the essential aspect of the nature of substance as substance.

Intrinsic nature. This most basic aspect of its essential nature will be called its "intrinsic" essential property, for it is the kind of essential property that a substance has in virtue of existing as something distinct from all the other substances in the world. It is what the substance is in itself, or its way of existing on its own.

Extrinsic nature. But its intrinsic essential nature is not all there is to the essential nature of a substance, if the substance is part of the same world as other substances (and the existence of other substances is not entailed by its essential nature, as in the case of parts of space). Insofar as the world is made up of substances that exist independently of one another, and insofar as those substances are related to one another in some way other than simply being parts of the same world, each substance must also have extrinsic essential properties relative to those other substances. It may have different extrinsic essential properties relative to each kind of substance to which it is related, but its essential nature must have some such aspects.

Thus, the essential aspect of the nature of substance as substance includes two kinds of essential properties: an intrinsic essential property and extrinsic essential properties. In other words, each substance must exist some way in itself and it must also exist some way for other substances that exist independently of it as part of the same world.

The intrinsic and extrinsic aspects of the essential natures of substance can certainly be distinguished by reason. The world is made up of substances, and we can think about each distinct substance as it is in itself, whatever that may turn out to be, because in order to exist at all, it must exist in some determinate way. And if there are other substances whose existence does not depend on what it is in itself, we can also think about what it is for other substances, assuming that it is related to other substances in some determinate way in addition to merely being part of the same world with them (and that relation is not part of its intrinsic essential nature, as in the case of parts of space relative to one another).

What a substance is in itself cannot be reduced to what it is for other, independent substances, because if its extrinsic essential nature were all there is to its essential nature, there would be nothing to be related to other substances. Relations need relata, or something that already exists. The relata are substances, and since every substance has an essential aspect to its nature as well as an existential aspect, each relatum has an intrinsic essential aspect. Since substances already have intrinsic essential natures, their relationships to other, independent substances must be a further aspect of the essential aspects of their natures as substances. Thus, each substance must have properties of both kinds, though different kinds of substances making up the same world may have different kinds of intrinsic and extrinsic essential natures.

The basic properties of the two basic substances. Spatiomaterialism postulates the existence of two basic substances, matter and space, and it assumes that each bit of matter coincides with some part of space or other. But as we have seen, matter and space have opposite natures as parts of the world. Though in both cases, it makes sense to think of the substances as consisting of many particular substances, their parts are related to one another in opposite ways. Bits of matter can exist independently of one another, but no part of space can exist without all the other parts of space. That is, space has a unique kind of wholeness about it, which matter lacks. The parts of space are dependent on one another, whereas the parts of matter are independent of one another. Being opposite in this way is crucial to their roles in making up the natural world, for nearly every new necessary truth that is supported by ontological philosophy comes from how space contains all the bits of matter.

Matter and space are, however, different basic substances. The existence of one does not entail the existence of the other. We do not know what bits of matter would be like, if they did not coincide with space, or even if that is possible. But each has an existence that is distinct from the other. That is the basic assumption of spatiomaterialism. That is, there would be a difference between parts of space with which bits of matter coincide and parts with which no bits of matter coincide, even if that never actually happens, given what physics implies about the nature of matter. (As we will see, however, space can be empty.)

Both space and matter must, therefore, have all the basic properties that entities must have to be substances at all, including both kinds of existential properties and both kinds of essential properties. Space and matter have existential properties in the same way. But since each basic substance is made up of parts in opposite ways, each has intrinsic and extrinsic essential properties in different ways. To make this clear, let us generate a catalogue of all their basic properties, starting with matter.

Basic properties of matter.Matter is a basic kind of substance, and since it is related to every other substance (of both basic kinds) in a determinate way, it must have both an intrinsic and extrinsic aspect to the essential aspect to its nature as substance.

Intrinsic nature of matter. Matter must have an intrinsic nature, even if matter cannot actually exist without being contained by space, because it must exist in itself in a determinate way in order to have an existence that is distinct from space. (That intrinsic nature may, therefore, be what matter is in itself as it coincides with space, but it is nevertheless different from the aspect of matter by which it is related to space.) What is more, however, matter comes in particular substances that exist independently of one another, and thus, each material substance must have an intrinsic property independently of all the other bits of matter.

The intrinsic property of each bit of matter is simply whatever it is in itself, that is, as something that has an existence distinct from every other substances. This could be anything a substance might be in itself (though as we shall see, it is the aspect of the essential nature of matter that makes it possible to explain phenomenal properties.) Since there may be different forms of matter, with different essential natures, the intrinsic properties of matter may be various.

Extrinsic nature of matter. Each bit of matter must also have an extrinsic aspect to its essential nature, because it is related to other substances which exist independently of it as parts of a single world. But according to spatiomaterialism, the substances that exist independently of each bit of matter include both space and other bits of matter, and thus, each bit of matter can have two fundamentally different kinds of extrinsic essential properties: one by which it is related to space, and aspect, which presumably depends on the former, by which it is related to other bits of matter.

Extrinsic nature of matter relative to space. One kind of extrinsic essential property of matter is how it is related to space. Every bit of matter must be capable of coinciding with some part of space or other, since that is what spatiomaterialism assumes the basic relationship between matter and space to be. Given the essential nature of space, as we have seen, that gives each bit of matter certain spatial relations (in three dimensions) to every other part of space. And since every other bit of matter coincides with some part(s) of space or other, coinciding with space also gives each bit of matter certain spatial relations to every other bit of matter in space. They are all contained by space.

Each bit of matter coincides with a part or parts of space. No assumption has been made about how much space bits of matter can coincide with. There may be different forms of matter contained by space, and different forms of matter may coincide with larger or smaller areas of space. Bits of matter may even be spread out in space unevenly. It depends on further aspects of the extrinsic essential nature of matter relative to space which will be discussed later (in Change: Contingent laws of physics), when we take up the ontological explanation of physics and how space and matter endure through time. All we assume here is that each bit of matter has, at the moment of its existence, a unity about it, so that it exists as a whole distinct from all other bits of matter.

Furthermore, since both matter and space endure through time, there may also be a temporal aspect to the extrinsic essential nature of matter relative to space. For example, it is possible that part of the extrinsic essential nature of bits of matter relative to space is that they move across space in some determinate way.

Extrinsic nature of matter relative to matter. Simply being contained by space gives each bit of matter determinate spatial relations to every other bit of matter, but that is not a basic part of its extrinsic essential nature, because it is entailed by its extrinsic nature relative to space, being contained by space, and the nature of space. But since other bits of matter in space exist independently of it, there can be a basic extrinsic aspect to its essential nature that is relative to other bits of matter is space. For example, if one bit of matter coincides with a particular part(s) of space, it may not be possible for other bits of matter to be located there, or not possible for bits of matter of certain other kinds to be contained by that part of space. Furthermore, if motion is an aspect of the extrinsic essential nature of bits of matter relative to space, their spatial relations may change over time, and there may be regularities about how their motions affect one another (that is, they may exert forces by which they change one anothers motion). Indeed, if there are different forms of matter, there may be ways that bits of matter, because of their relative locations and motion, affect one another’s forms.

This is how physical properties are explained ontologically. The basic laws of physics describe regularities in the motion and interaction of basic particles, and the properties they must mention in order to predict or control what happens are called "physical properties." Hence, the truth of the basic laws of physics can be explained ontologically by the extrinsic essential natures of bits of matter relative to space and relative to other bits of matter, since their extrinsic properties include how the bits of matter move and interact with one another. Indeed, that is how spatiomaterialism will explain the basic laws of physics. In other words, physical properties will turn out to be extrinsic aspects of the essential nature of matter with respect to space, with respect to matter, or with respect to both.

It should be noticed, however, that this way of explaining physical laws makes a distinction between two different aspects of the extrinsic essential aspect of matter, implying that there is a difference between two kinds of physical properties. The physical properties having to do with spatial relations and motion are different from those having to do with interactions, because the extrinsic essential natures of matter relative to space is different from their extrinsic essential natures relative to other bits of matter. Indeed, this is, as shall see, the beginning of a deeper (that is, ontological) explanation of the truth of the basic laws of physics.

Basic properties of space.Space is also a substance enduring through time, and since, as a substance, it exists independently of matter, it must also have two aspects to its essential nature: an intrinsic and an extrinsic essential aspect to its nature as a substance. That distinction arises for space because of its relationship to matter, and unlike bits of matter, no such distinction between intrinsic and extrinsic properties can be made in the case of parts of space.

Space has an opposite nature from matter. It has a unique wholeness, because its parts cannot exist at all unless they are all related to one another geometrically in three dimensions. They are not independent substances. Since their relations to one another are part of the essential nature of each part of space, they do not need any further aspect of their essential natures by which to account for the relations to one another. Their essential natures include their relations to one another, and thus, there is no way to distinguish between an intrinsic and extrinsic aspect to their essential natures.

The reason for distinguishing an extrinsic from the intrinsic aspect of the essential nature of a substance was that when a substance exists together with other substances as parts of the same world, it needs some way of being related to them (beyond merely being parts of the same world). But since that was to assume that the substances exist independently of one another, we excluded substances whose essential natures entailed the existence of other substances, for they must already have relations to those other substances as part of their essential nature. That holds in the case of the parts of space.

To be sure, each part of space has an existence that is distinct from every other part of space. But they all have the same kind of essential nature, for they each have the same kind of relations to all the other parts of space. What makes the parts of space different from one another is the particular parts of space to which they have those relations. And since their relations to one another are part of their essential nature, they need only their essential natures to be related to all the other parts of space. That is why the existence of any part of space entails the existence of all the other parts of space.

It is possible to put this point paradoxically. Since the intrinsic nature of a substance is what it is in itself and its extrinsic nature is what it is for other substances, one might say that the intrinsic nature of each part of space relative to other parts of space entails its extrinsic nature, because what it for other parts of space is just what it is in itself as a part of space. But the paradox just emphasizes that no distinction can be made between the intrinsic and extrinsic natures of parts of space relative to one another.

In the case of space, therefore, the essential nature of each part of space as a part of space includes all its relations to other parts of space. That is the wholeness of space, and though it means that there is no distinction between the intrinsic and extrinsic aspects of the essential nature of each part of space relative to other parts of space, it also has implications for both the intrinsic and extrinsic essential nature of space relative to matter.

Intrinsic essential nature of space relative to matter. To exist independently of matter as its container, space must be something in itself. It must exist in a determinate way apart from space. That is the intrinsic essential nature of space relative to matter. But it is a nature that space can have only as a whole.

The essential aspect of the nature of space as a whole includes its being made up of parts with geometrical relations to one another in three dimensions, that is, being made up of all the locations in three dimensional space. This interdependence of the parts of space means that the essential nature of each part of space includes having geometrical relations to every other part of space. In both cases, the essential nature is the aspect the substances have in virtue of how they exist, and since the parts of space necessarily make up the whole of space, it is the same aspect of these substances that characterizes the essential nature of both part and whole. That aspect of the essential nature of space is the intrinsic nature of space.

There is, however, a part-whole relation involved in the essential nature of space. That is, the part is not identical to the whole, because it is only part of the whole. The whole is identical to all the parts. Thus, the existence of space as a whole entails the existence of each of its parts. But since all the parts must exist, if any one of them exists, the existence existence of any part of space also entails the existence of the whole. (Though there is a necessary relationship between them, it is, at this point, true because of what we mean by the terms used, that is, an analytic truth, not an ontologically necessary truth. It is an ontologically necessary truth about the world only if spatiomaterialism is the best possible ontological explanation of the world.)

Neither part nor whole is prior to the other. Space cannot be explained ontologically as a collection of parts of space, because no part of space can exist without the whole. Likewise the parts of space cannot be explained ontologically by the whole, because the whole of space is just all the parts of space.

What makes the parts of space different from one another is not their essential natures, but the particular parts of space to which each part has the geometrical relations entailed by its essential nature. This is to assume that all the parts of space have the same kind of essential nature, and that is the assumption we are making, since it is the simplest assumption we can make about the nature of space. But it does imply that space is infinite, both in its divisibility and its extent, and thus, the essential nature of space (or its intrinsic essential nature relative to matter) is an aspect of something that is infinite. (Of course, if it were to turn out that space is finite, as contemporary cosmology assumes, a much more complex assumption would have to be made about space, because if space has edges, the parts of space would have to have different essential natures. But space would presumably still have an essential nature that characterizes both part and whole equally, since they would still entail one another, and that would be its intrinsic nature relative to matter..)

The part-whole relation that holds for space is the unique wholeness of space, and since it is an assumption of spatiomaterialism, there is no genuine ontological explanation of it. But it is a remarkable essential nature, and since it is so basic to the spatiomaterialist explanation of the world (including its explanation of many further part-whole relations, as we shall see), a few comment might make it easier to grasp what is involved in taking space to be a substance.

The parts of space are puzzling. Mathematicians call them points because the simplest parts of space have no spatial dimensions. But since they make up space as a whole, there are infinitely many of them in any finite distance. That is called the "continuousness" of space, or its infinite divisibility. But since it has been assumed as part of the essential nature of space, there is no ontological explanation of it in spatiomaterialism. It is just another aspect of the wholeness of space.

As explained above, the wholeness of space implies that parts of space do not have extrinsic essential natures relative to one another. This is because what forces us to recognize that any substance has an extrinsic nature is that it can exist independently of other substances and is nevertheless related to them in some more determinate way than simply being parts of the same world with them. An extrinsic essential property characterizes what the substance is for the other substance, or what it contributes to how they are related. But since parts of space cannot exist independently of one another, they lack extrinsic essential natures as parts relative to other parts of space. Their relations to one another are part of their essential natures. The existence of one part of space entails the existence of all the others.

To say that the parts of space lack extrinsic essential natures relative to other parts of space makes it seem that they do have intrinsic essential natures relative to other parts of space. After all, since each part of space does have an existence that is distinct from every other part of space, it must have something in itself. But since what it is in itself includes it geometrical relations to every other part of space, its intrinsic nature seems to be just its essential nature as a part of space. Thus, it is less misleading to say that no distinction can be made between extrinsic and intrinsic natures of parts of space relative to other parts of space. That is just the unique part-whole relation about space.

It is the unique wholeness of space that makes it odd to think of space as a substance. Space does not seem to be a substance because it is everywhere. That makes it seem like nothing to us, because we are, as rational beings, parts of the world (that is, located in space), and we use the structure of space as a way of thinking about the world. We think of material objects as what is substantial about the world, and we take for granted that such substances have have spatial relations to one another, because that is also a most basic aspect of our way of thinking about the world. (That is, spatial imagination is built into every perception). But the appearance that space is nothing is just the essential nature of space (both part and whole). That is just its intrinsic nature relative to matter. And it is because the parts of space exist in such a way that they make up a three dimensional whole that the bits of matter that coincide with parts of space are related to one another. Thus, to see as nothing is, in effect, to grasp its intrinsic nature relative to matter. That is how it appears from "inside space," so to speak.

On the other hand, to think of space as a substance is, in effect, to see space from the outside, rather than from the inside. It gives us the same angle on space that space itself gives us on material objects, because it provides a context in which we can see how space is related to other things, most relevantly, how it is related to bits of matter.

It may help, therefore, to step back a bit and think about what we are doing in taking space to be a substance. We are recognizing that space is an ontological cause of the things that are found in the natural world that is different from matter, that is, as a separate principle, along with matter, in explaining everything. Space is something self-subsistent that helps constitute the world. It may not be possible to have a deeper understanding of the intrinsic essential nature of space relative to matter than what we know by its role, along with matter, in explaining the world ontologically. That is the step that is required, as I have suggested, to see the world from the outside. But "from the outside" is itself a spatial metaphor. You cannot see space from the outside, for taken literally, the outside of anything is always inside space itself. Thus, as I have suggested, it may be better to think of substantivalism about space as what we must assume in order to have a God’s Eye View of the world. After all, space is something that God would have had to create, along with matter, in order to create the natural world. But neither can that description be taken literally, since, as naturalists we deny that there is any being that transcends the world. Thus, the best we can do is, perhaps, just to recognize that the existence of space as a substance enduring though time is just an independent, basic assumption of the most complete ontological explanation that we can give of the world. Everything else in the world is located within the three dimensions of space. That is the bottom of our understanding of the nature of the world, according to ontological philosophy.

Extrinsic essential nature of space. Just as bits of matter have an extrinsic essential nature that allows them to coincide with space space, so space must have an extrinsic essential nature that allows it to coincide with bits of matter. But since space is a whole with parts that differ from one another as different locations in its three dimensional structure, it is not clear whether this extrinsic essential property characterizes the essential aspect of space as a whole or its parts.

Particular bits of matter clearly coincide with particular parts of space. But if any bit of matter coincides with more than one part of space, coinciding with bits of matter is also clearly something that parts of space must do jointly. Furthermore, it is only because many different bits of matter are all contained by the same whole space that coinciding with space gives them spatial relations to one another. Thus, what coincides with them seems to be space as a whole as well as its parts. That is, bits of matter are contained by space

On the other hand, coinciding with bits of matter is something space does to each bit of matter separately, not how space relates to matter as a whole, because matter is not a whole, but just all the bits that exist. To be sure, space coincides with all the bits of matter in the world. But that is just the spatiomaterialist assumption about how these two basic substances exist together as a world, not something that characterizes the essential natures of space as a whole and matter as a whole.

What makes the nature of space problematic is its unique wholeness, or how space is made up of parts and yet is still one. For our purposes, therefore, it is enough to recognize that the capacity to contain bits of matter is the extrinsic essential nature of space, both whole and part, though each bit of matter coincides with some part (or contiguous parts) of space or other(s). And if different varieties of material substances are contained by space in different ways, it must have all the extrinsic essential properties required to do so.

Furthermore, space must also have extrinsic essential properties corresponding to all the extrinsic essential properties of bits of matter relative to space. That is, it must give bits of matter motion through space, if that is how they coincide with space, and it must enable them to interact in all the ways that are involved in the extrinsic essential natures of various kinds of bits of matter relative to other bits of matter. These are also extrinsic essential properties that space both has as a whole and in each part.

Nor is that necessarily all there is to the extrinsic essential nature of space (though relativistic physics holds, in effect, that it is). Since space is a substance, which exists independently of matter, it is possible for space to interact with bits of matter in other ways. Indeed, that is what we shall need to assume in order to explain ontologically how Einstein’s special and general theories of relativity are true. The basic assumption of our ontological explanation of relativity will be is that light always has a determinate velocity relative to space itself, and in explaining special relativity, we will hold that space imposes certain (Lorentz) distortions on material objects moving through space with high velocity. In the case of general relativity, we will assume, further, that the accumulation of large quantities of matter in space alters the velocity at which light moves in nearby regions of space.

This is to hold that the parts of space can contain bits of matter in different ways in the regions around centers of gravity But that is not to say that are any changes in the relations among the parts of space itself. It is only to say that there is a change in how bits of matter coincide with space in those regions. In short, the assumption we shall make in explaining Einsteinian relativity is that space has an absolute, uniform Euclidean three dimensional structure, and that that structure is not changed even though the extrinsic essential nature of space includes interactions with matter that change the state of certain parts of space and, thereby, change how bits of matter coincide with space in those regions. (See Change: Special theory of relativity and Change: General theory of relativity.)

In a more speculative way, I will suggest that space also plays a role in explaining the truth of quantum mechanics, the basic particles recognized by physics, and certain issues in cosmology. Those roles would characterize further the extrinsic essential nature of space, both part and whole. (See Change: Quantum mechanics and Change: Cosmology.)

Properties as Objects of Knowledge.Ontological philosophy explains properties as aspects of the substances it postulates. But when philosophers begin their argument from the point of view of the cognitive subject by reflecting on how they know, they see properties as objects of knowledge, and that gives rise to philosophical problems, including problems about the nature of properties. To take properties as objects that are known in some way is, in effect, to see them as more basic than substances, because the objects that have them seem to be nothing but something that has properties of certain kinds that are present to the subject and to which he can refer. This is the source of the problem of mind. It can be seen that there is a difference between two basic kinds of essential properties (which ontological philosophy explains as the difference between intrinsic and extrinsic essential properties), but epistemological philosophy has no way to explain how they are related to one another because it takes properties to be basic. In its contemporary form, as we shall see, it infects materialism. But let us begin by seeing how the problem of mind arises.

The Problem of mind.The problem of mind arises when naturalists discover that there is a basic difference between properties which was not obvious at first. In our naive or natural attitude toward the world, we take the natural world to be simply what we perceive, as if the objects in space, including our own bodies, were simply what they appear to be. This is a form of realism, because it is to assume that those objects in space would exist even if we were not perceiving them. But it is naive, because it assumes that the objects being perceived actually have the properties that they appear to have in perception, including not only their locations, shapes, and dispositional properties (such as how they move and interact), but also their colors, odors, sounds and tactile properties, such as hot and cold, wet and dry.

The latter properties are distinctive, for they are qualitative properties, or properties that are simply a quality of some kind that is immediately present to the perceiver. When I perceive that a leaf is green, for example, the surface of the leaf appears green, and the greenness is an object of my immediate awareness. What I mean by "green" is that kind of quality that seems to inhere in the surface of the leaf, and I cannot define "green" any more precisely than that, because what I mean is something that is intrinsic to the object I am aware of. The quality is what makes it the kind of object it is. Such qualitative properties are now often called "qualia," and they are involved in everything we perceive, including not only the colors that objects have to vision, but also the odors they have to smell, the sounds they have to hearing, and certain tactile properties they have to touch. Such qualities, or qualia, also characterize one’s own body, but one’ own body has additional qualities that are perceived in a different way, such as pains, tickles, itches, and the like, for they are not perceivable by others.

The problem of mind arises when it is recognized that the qualia that are immediately present to us in perception are not located in the objects we perceive in the space in and around our bodies, but are somehow part of us as subjects, most closely connected to our brains. That is, the mind become a problem with the acceptance of critical realism.

Naturalists are forced to recognize that qualia are subjective in this sense when they discover that perception is a physical process in which the objects stimulate sensory organs and that somehow gives rise to the qualia we have. In each sensory modality, what causes the experience is a chain of causes and effects that starts in the object being perceived, proceeds through the body, making events occur in the brain, and the qualia come at the end of that causal chain. Thus, qualia must somehow be part of one’s brain. And if we follow this argument to its conclusion, naturalists also come to recognize that the space in which sensory qualia seem to be located is itself also merely phenomenal and, thus, distinct from the space in which the physical objects actually exist.

This discovery about perception is called "critical realism" (or "representative realism"). It is realism, because it holds that the objects being perceived really do exist in physical space as the causes of the appearances we have in perceiving, including our bodies. But it is critical, because it does not take the qualia that make up those appearances to be properties in the objects that give rise to them, but rather as parts of the subject, where their function is apparently to represent those properties in the material objects in real space to the subject. Likewise, it is critical because it recognizes that the spatial relations that appear to hold among the qualia in perception are different from the spatial relations that hold among the material objects in real space.

Thus, critical realism about perception makes it clear that objects with physical properties in real space exist somehow "beyond" the (complex) phenomenal properties we have. Since material objects in real space have physical properties, it is to discover that we must distinguish the qualia and their configurations in phenomenal space from physical properties. They are what we call "phenomenal properties."

Critical realism gives rise to the so-called problem of mind, for it seems that the subject to whom the configurations of qualia appear is a radically different kind of entity from the material objects in real space. Material objects have physical properties, including not only the physical dispositions that make them causes of the qualia that appear in perception, but also relations in real space. But the subject is radically different, because he is something to which phenomenal properties appear.

When we reflect on the perceptual appearances we have as perceiving subjects, furthermore, we recognize that they play distinctive roles in our processes of knowing and doing. There are other appearances similar to perceptual appearances, albeit fainter and less detailed, which play other roles. Traditionally, the former are called "ideas of perception," and the latter are called "ideas of memory and imagination." But they, and perhaps other appearances that our mental processes have to us in thinking and feeling emotions, are all phenomenal properties.

To acknowledge this fundamental difference from material objects, the subject calls himself "mind" and contrasts it with his body, which is just an object in space (albeit a special one, since it is the one through which he acts). The mind-body is problem is how the mind and body can be parts of the same world, that is, what are their natures and how are they related to one another.

Theories of mind.This problem about the nature of mind is arguably the source of all the problems encountered in modern philosophy, and it arises in contemporary philosophy as the problem about the relationship between physical and phenomenal properties. The question is how to explain the natures of the two radically different kinds of properties that are known from the point of view of the critical realist as parts of the same world. There is not much of a problem for ontological philosophy, and so let us consider why before we derive the various positions on the nature of mind defended by traditional, epistemological philosophy.

Ontological theories of mind.A solution to the problem of mind would pay back one of the mortgages we took out on spatiomaterialism, for it would explain how beings like us are conscious. And it can be found in the differences among the basic properties that are entailed by spatiomaterialism, or indeed, that are entailed by any materialism that accepts our notion of substance and takes ontology to be explanatory. Physical properties are different from phenomenal properties as the extrinsic essential natures of bits of matter are different from the intrinsic essential natures of matter.

Material objects in space with their physical properties present no problem, for they are precisely what a naturalistic ontology is intended to explain, and though we will put off the detailed ontological explanation of physical properties, we have already seen how they will be explained as aspects of the extrinsic essential natures of bits of matter in space.

As naturalists, we assume that the subjects who perceive the world are themselves material objects in the world. And we have good reason to believe that they are rather special material objects, for they are animals with complex brains. Spatiomaterialism will throw much light on how the brain is responsible for the behavior and cognitive processes that we ordinarily believe take place in experiencing subjects like ourselves. (See Change: Evolutionary stage 6 and following.) But they are basically explanations of how the brain is a machine that enables subject to have the beliefs, desires, and behavior that we do, and for now, let us take it for granted that there is such an explanation.

Assuming, therefore, that the brain can account for the behavior and cognitive capacities of subjects like us in the natural world, all that is needed to solve the problem about mind is an explanation of the existence of phenomenal properties that shows how it is possible for material objects to have them. The obvious explanation of the nature of phenomenal properties, given the kinds of basic properties that substances have, is that they are the intrinsic essential aspect of the nature of some bits of matter that help make up the brain. That would mean that phenomenal properties are related of physical properties as the intrinsic essential nature is related to the extrinsic essential nature of some bits of matter that help make up the cognitive subject. Since bits of matter must have both kinds of essential properties, this ontological explanation would imply that there is an ontologically necessary relationship between physical and phenomenal properties. That explanation of how the connection is necessary is what solves the problem about mind that plagues contemporary philosophy, as we shall see below: Properties: Ontological theory of the necessary connection.)

This is enough to show that consciousness is possible, if spatiomaterialism is true, though it depends, of course, on showing that there is a form of matter that helps to constitute the conscious subject whose intrinsic essential nature can plausibly account for all the phenomenal properties. Since they include not only sensory qualia, but the complex configurations of them in phenomenal space, there is more to the explanation of consciousness than this ontological explanation of the basic properties of substances. To explain those complex phenomenal properties is to explain what I will call the "unity of consciousness." We cannot do that, however, until we have considered the forms of matter entailed by spatiomaterialism (as we shall in Change: Contingent laws of physics), and explained how the brain works (in we shall in Change: Evolutionary stage 6 and following). For the spatiomaterialist explanation of the unity of mind, see Change: Unity of consciousness.)

In order to suggest how such an explanation is plausible, however, let me just say here without further defense that the relevant form of matter will turn out to be the photons that are generated by the active mammalian brain. That is, the firing of neurons involves the rapid acceleration of charged objects (ions), and since in mammals, many such neurons fire in a synchronized way (throughout the projection from the thalamus to the neocortex), the whole brain is like a complex antenna generating photons with a very complex structures in space and time. The intrinsic essential aspect of the nature of those bits of matter can explain phenomenal properties, including not only the simple qualia but also how they appear to be configured in phenomenal space, not to mention the differences between perception and memory and imagination.

Epistemological theories of mind.Epistemological philosophy does not attempt to explain things ontologically, except as an afterthought to an argument that attempts to justify knowledge of some kind, that is, as realism about the objects of which it tries to show that we have knowledge. Instead, it uses reflection on how we know to introduce a theory about the nature of reason, and and starting with some kind of knowledge that is taken as unproblematic by that theory, it tries to justify knowledge of something else. Success is realism, but realism leads to metaphysical dualism, that is, an ontology that postulates kinds of substances that are so utterly different from one another that it is not possible to explain how they are related to one another at all. And the ontological problems of realism lead, as we have noted, to anti-realism, the denial that we have the kind of knowledge defended (which may entail it own distinctive metaphysics).

Though both modern and contemporary philosophy start by reflecting on how we know, the problem of mind took different forms for each period, because they had different explanations of how we know, that is, different theories about the nature of reason. Modern philosophers had a theory about the nature of reason that was based on reflecting on how individual minds know, and so its realism led to mind-body dualism. Contemporary philosophers had a theory about the nature of reason that was based on reflecting on knowledge as an intersubjective process, and so its realism led to property dualism (and puzzles about the relationship between physical and phenomenal properties). Let us consider each in turn.

I will give a brief account of the problem of mind in modern philosophy in order to provide a context in which to understand the approach of contemporary philosophy.

Modern philosophy. Though the ancient atomists were critical realists, naive realism otherwise dominated ancient and medieval philosophy. It was the rise of modern science that led to the rediscovery of critical realism. Modern science presupposed an ontology that ascribed only physical properties to objects in nature, and it implied that perception depends on a chain of causes and effects starting in the object and ending somewhere in the brain. Though modern scientists and philosophers alike recognized that sensory qualia are parts of the subject, it was Descartes who first saw how to use it to pursue a new form of epistemological philosophy. Descartes so-called method of doubt was to deny everything that it was possible to doubt. As a critical realist, that led him to doubt the existence of his own body and the natural world in which it exists.

Realism about the external world: mind-body dualism. Descartes could not doubt that he was having ideas, and thus, he argued that he had indubitable knowledge of his own existence. Descartes affirmed the certainty of this knowledge by asserting, "I think, therefore I am." From this foundation, Descartes introduced a theory about the nature of reason that implied that any ideas that are equally clear and distinct are true, and thus, he set out to show that we could know both the existence and nature of the external world. Given his goal, the success of modern realism was realism about the world of material objects in space. Descartes' plan was to justify modern science philosophically, that is, from a foundation that is prior to what science learns about what happens in the natural world from observation. But apart from other difficulties in his argument, his project foundered on the problem of mind-body dualism.

The rational method he used was discussed in Method, and the dualistic ontology to which it led was discussed in Ontology. Descartes' dualism of mind and body was the problem of mind in modern philosophy. Critical realism made it clear that physical properties are fundamentally different from phenomenal properties, and that made it seem that the objects with those properties were substances with opposite kinds of essential natures, namely, mind and body. As Descartes saw it, body is always divisible into smaller parts, whereas mind has a unity that does not permit division, because all the qualia that seem to be located in space have an appearance for the subject at the same time. And whereas mind can think in this sense, body cannot, for it has only the properties that physics ascribes to it (which Descartes thought came down to extension, that is, geometrical properties). The difference in their essential natures left no plausible explanation of how they interact, and attempts to solve it (such as Spinoza’s claim that substance can have two opposite essential natures and Leibniz’s claim that nothing exists but minds, or "monads," as he called them) were embarrassing failures.

Anti-realism about the external world: idealism. The inability to explain how mind and body are related as parts of a single world doomed attempts to justify knowledge of the natural world, and the British empiricists (Locke, Berkeley and Hume) followed the skeptical argument to its conclusion, doubting in the end that the natural world is anything but perceptual ideas (or impressions of sensation, as Hume put it). Locke did not recognize that the principle of empiricism (that all our knowledge about the natural world comes from experience) leads to skepticism about the existence of the natural world, but Berkeley embraced this skeptical conclusion ontologically and defended idealism explicitly. However, Hume and the subsequent tradition of empiricism merely dismissed all attempts to explain the natural world ontologically as meaningless metaphysics (though idealism is all that empiricism has to offer to those who look for a theory about what exists).

The second phase of modern philosophy struggled with the problem of mind in a different way. Kant held that science has knowledge only of the phenomenal world, and thus, he was not a realist. But he was still a dualist, because he believed that, in addition to mind, there are things in themselves in addition to the phenomenal world. Hegel sought to overcome Kant's dualism and defend the claim of reason to know the real nature of what exists, but the only way he could do was by defending absolute idealism (that is, by holding that everything, including the natural world, can be reduced, dialectically, of course, to an idea at the bottom).

Spinoza stands out among modern philosophers, because his way of denying mind-body dualism was to deny that body is a different substance from mind. He took mind and body to be related as two attributes of the same substance. (That is close to the implication of ontological philosophy, except that Spinoza believed that the world is a single substance. He could not explain the relationship between the attributes of thought and extension as the relationship between the intrinsic and extrinsic essential aspects of substances, because there are no relationships among substances in his view.)

Contemporary philosophy. Naturalism is the attitude of contemporary philosophy. In the twentieth century, continuing advancement by science in explaining the natural world, discovering laws of nature and various mechanisms embodying them, made the abstruse and inconclusive arguments of philosophy of modern philosophy seem fundamentally misguided. Philosophers abandoned the Cartesian method and its metaphysical problems in favor of an explanation of how we know that derives from reflecting on knowledge as an intersubjective process, and that brought with it a commitment to naturalism. And contemporary philosophers accepted natural science, with some reservations, as the most adequate way of knowing we have. Thus, the problem that mind poses for contemporary philosophers can be seen as a question about how a science of consciousness is possible. Contemporary philosophers assume, as naturalists, that what modern philosophers called "mind" must somehow be part of the natural world, and though they could dismiss mind-body dualism, it was harder to deny the difference between physical and phenomenal properties. Those who affirm the existence of phenomenal properties as well as physical properties are called "property dualists." For naturalists, therefore, the question became how phenomenal properties can be included as something characterizing the natural world being explained by science, even though science refers only to physical properties.

For present purposes, let us take "physical properties" to include functional properties, such as "being a clock" or "conveying signals." They may not be reducible to physical properties, but since no one denies that they "supervene," at least, on physical properties, all the causal connections in particular cases come down to basic physical properties. And the issue is how phenomenal properties are related to physical or functional properties.

Contemporary philosophers have taken great care to show that phenomenal properties are different from physical properties, for example, in famous arguments by Thomas Nagel, Frank Jackson, and Saul Kripke. By asking what it is like to be a bat, Nagel (1979, 1986) was pointing to a subjective aspect of experience that cannot be known by the "view from nowhere", that is, by natural science. Jackson (1982) made it clear that phenomenal qualities, or qualia, are themselves objects of knowledge by pointing out that Mary, a neurophysiologist who studied the physical mechanism of color perception in a laboratory devoid of red objects, would come to know something more about the perception of red when she left the room and actually saw something red, namely, how red appears to the subject. And Kripke (1980) showed that properties rigidly designated by how they appear to subjects cannot be identical to physical properties because the connection is not metaphysically necessary, as it would have to be, if they were identical.

For those who are inclined to take natural science as revealing the basic nature of the world, the problem of mind is how there can be a science of consciousness. It is most obviously problematic when science is understood as using a method that bases its conclusions on observation in one way or another. This reliance on observation is a basic tenet of its empirical method as traditionally understood, for example, by empiricists, logical positivists and most practicing scientists. (Though there are well known problems in the philosophy of science about the theory-ladenness of observation statements, it is agreed on all sides that observation depends on perception, that is, on the use of our sensory organs to discover the states of objects in space.)

The reason that this tenet of the empirical method makes consciousness a problem for science is that phenomenal properties are apparently knowable only by reflection. We have seen how the difference between physical and phenomenal properties was discovered -- that is, by reflecting on the causal explanation of perception from the point of view of the perceiving subject. But it also seems that our only "evidence" that psychological states involve phenomenal properties comes from each of us reflecting on our own psychological states. The nature of simple qualia, for example, what red qualia are like, is not revealed to observation. They are private to each individual subject.

There are ways of observing the brain in operation, and new ways are being developed. But no one has found a way of using such observations to demonstrate that brain states involve phenomenal properties. Indeed, neurophysiologists don’t expect their methods ever to show either the existence of phenomenal properties or how qualia appear.

To be sure, there is evidence for the existence of phenomenal properties in what people say about their psychological states. But that evidence depends on scientists interpreting the other’s talk of qualia and phenomenal properties as references to objects of the same sorts they each know privately by reflection on their own phenomenal properties. The verbal behavior itself does not seem to depend on anything but physical causes.

The difference between reflection and perception makes it doubtful, therefore, that science will ever be able to know about phenomenal properties.

Anti-realism about phenomenal properties: eliminative materialism. One quick way of dealing with this problem is simply to deny there are any phenomenal properties. This is, in effect, anti-realism about phenomenal properties from the point of view of science, though it is usually called "eliminative materialism," by the kind of ontology it defends.

In one version, eliminative materialism holds that the need for talk of phenomenal properties will eventually be eliminated, at least from science, as science explains all the phenomena relevant to psychology in its own terms. That would show that our traditional talk about phenomenal properties (and psychological states, such as perceptions, beliefs, desires, and the like) is just a mis-description of what really exists, which is fully described by physical properties. (See Churchland 1995.)

It is also possible to argue that we are fooling ourselves to think that traditional talk about phenomenal properties is meaningful in the first place. (See Dennett 1991 and Rorty 1979.)

But eliminative materialism does not show how a science of consciousness is possible. Rather, it holds that a science of consciousness is not necessary because there is nothing to be explained. The problem of mind arises only for those who are realists about phenomenal properties and believe that they exist in addition to physical properties.

Realism about phenomenal properties: property dualism. During most of the century, empiricism in psychology took the form of behaviorism, the attempt to explain human beings in terms of laws describing their observable behavior. Consciousness was thereby banished from science. But that is puzzling to contemporary naturalists, for they expect natural science to explain everything in the natural world, and they know, as reflective beings, that they themselves are conscious. They are realists about phenomenal properties, and that makes them property dualists, because they recognize the existence of phenomenal as well as physical properties. And the problem of mind can be seen at the attempt to show how science can study consciousness, that is, how it can justify theories that refer to the phenomenal properties of psychological states. There are several possibilities.

Emergentism. The most obvious way for science to include consciousness would be to take mind to be an immaterial substance that is located in space along with bits of matter. Or if we call everything located in space "matter," it is to hold that some bits of matter have phenomenal properties that play a causal role in the natural world. If phenomenal properties of bits of matter did somehow make a difference to what happens in nature, they would be not only effects of physical causes, but they would themselves be efficient causes, and their existence could be detected empirically. Science could know about them in the same way it knows about other unobservable entities, such as electrons and force fields. Bits of matter with phenomenal properties would have to be mentioned by the best explanations of what can be observed through perception alone.

It is conceivable, at least, that phenomenal properties would have to be introduced by some branch of science, such as neurophysiology. The mechanisms found in the brain might provide no way of explaining, for example, why human beings say that they have phenomenal properties or why they call certain sensations green and others red. If all possible physical explanations were ruled out, the best explanation might be to hold that reports about phenomenal properties depend causally on how psychological states appear to the subject having them, which would mean that phenomenal properties are efficient causes. Phenomenal properties would then be unobservable entities of neurophysiology.

Any such neurophysiological discovery would, however, have serious implications for physics. The grounds for believing that there are phenomenal properties playing a causal role would be that no physical mechanism can explain certain verbal behaviors, and that would imply that there are efficient causes at work in brains that are not physical properties. This would be shocking, for physics is thought to be causally complete, in the sense that physical properties are sufficient, in principle, to explain every kind of event that happens to what is located in space.

It might be argued that the reason physics has not noticed the causal role played by phenomenal properties is that they are emergent and make a difference only in highly complex physical objects, such as brains, which evolve (or in complex functional systems generally). But in order for phenomenal properties to be effective in brains, neurophysiology would have to predict something different from what physics would predict for the same situations on the basis of physical properties. Thus, physics would have to come to believe that some material objects have properties in addition to the physical properties that it has already recognized and that these new properties affect how physical entities move or interact in certain situations. In other words, this kind of emergentism would be causal. Such a discovery would contradict physics as we know it. At a minimum, it would show that physics is not causally complete.

A science of consciousness could, therefore, be established by a scientific discovery of the kind that even the most hidebound defender of the traditional view of the empirical method could not deny. That would be a scientific solution to what has heretofore seemed to be a philosophical problem about mind. There is, however, no evidence at present suggesting that phenomenal properties should be introduced as unobservable (that is, not directly perceivable) theoretical entities of neurophysiology. It seems quite unlikely to contemporary naturalists, considering how radically physics would have to be mistaken. And if phenomenal properties are, as ontological philosophy suggests, the intrinsic essential properties of certain kinds of matter involved in the function of the brain, they have no causal role. All the causal roles are played by extrinsic essential properties, that is, the physical properties already recognized by science.

Epiphenomenalism. Another way founding a science of consciousness would be to accept reflection as a form of observation in science. Though reflection has long been the province of philosophy, this avenue is open to naturalists who think of philosophy as "continuous with" science.

This trend in recent philosophy of science explicitly abandons epistemology in the traditional sense of providing an a priori foundation for the justification of science and its method (Kitcher 1992; Rosenberg 1994). Instead of "first philosophy," it proposes to use the results of science itself to justify and improve the methods of science, which has given it the name "naturalized epistemology" (after Quine 1969). For example, scientific discoveries about the mechanisms of human cognition could be used to improve evidence gathering methods in science as much as discoveries about the accuracy of any measuring instrument. But those same human beings have a capacity for reflection as well as perception, and thus their reflection on phenomenal properties could be considered a way of gathering evidence about the natural world which is just as legitimate as their perception of physical properties. To naturalists of this kind, therefore, it may seem there is no obstacle to a science of consciousness. Indeed, these days, cognitive scientists often use reports about reflection on phenomenal properties as evidence, a practice recently defended by Goldman (1997).

To recognize reflection, including what can be known only by reflection, as part of the data base of natural science is, however, a trivial solution to the problem of mind. It overcomes the epistemological obstacle to a science of consciousness by, in effect, redefining "science" to include a form of knowledge that has traditionally been taken as the foundation of by philosophy.

It will not be acceptable to naturalists who cleave to a more traditional notion of empirical science as based on observation by perception. They will dig in their heals from fear of opening the door to other forms of private knowledge in science, such as the intuitions by which rationalists justified their metaphysical systems. And attempts to draw a new line of demarcation between science and philosophy that will include reflection on phenomenal properties but exclude the supposed certainty of clear and distinct ideas would seem like mere gerrymandering.

Even if there were no epistemological objections to reflection, however, this avenue to a science of consciousness would lead to ontological problems for science. It would complicate the scientific view of the natural world in a way that is quite problematic, for it would be to acknowledge the existence of properties that simply do not fit together intelligibly with the properties already recognized by science. The latter come down to properties mentioned by physics. Specifically, physical (and functional) properties seem to be responsible for all the behavior and internal processes found in complex organisms like us. Thus, to acknowledge the existence of phenomenal properties on the grounds that they can be "observed" in nature through reflection on what experience is like would be to recognize that some natural objects, human beings, at least, have properties of a fundamentally different kind from those already recognized by natural science. And if physicists are correct in believing it to be possible, in principle, to explain everything that happens in nature by the efficient causes picked out by physical properties, two facts about these properties follow. One is that phenomenal properties are somehow effects of the physical (or functional) properties of such organisms. The other is that having phenomenal properties cannot itself have any effect, in turn, on physical or functional properties. In other words, phenomenal properties would be epiphenomenal relative to physical (and functional) properties.

Epiphenomenalism is, at best, an inelegant ontology. It takes phenomenal properties to be "nomological danglers," in Feigl’s (1958) famous terms. Epiphenomenalists can insist, of course, that there is a causal necessity about the connection between physical (and/or functional) properties and phenomenal properties. But it would be just an assumption, for they have no explanation of why physical (or functional) properties give rise to phenomenal properties. Nor any explanation of why phenomenal properties should be impotent.

Thus, if the goal of science is to discover all the most basic laws of nature, epiphenomenalism would mean that those most fundamental laws include not only the basic laws of physics, which describe efficient-cause connections, but also psychophysical laws, which describe a regular connection between physical (and/or functional) properties and phenomenal properties. (For example, see Chalmers1996, pp. 87, 170-1, 274-5.)

Or, to use Kripke’s (1980, p. 153-5) famous metaphor, God, in creating such a world, would have to go back, after creating all the physical objects and putting them together as a natural world, and tack on the phenomenal properties. The extra effort required belies their odd status. No one finds epiphenomenalism satisfactory. (It repels even Chalmers 1996, p. 160.)

Necessary connection between physical and phenomenal properties. Ontological philosophy provides, as we have seen, a way of avoiding the problem of epiphenomenalism. Though it accepts property dualism, it reveals a necessary connection between physical and phenomenal properties, and that would found a science of consciousness, because it would show that phenomenal properties are already part of what exists according to science. Contemporary philosophers recognize that demonstrating a necessary connection between physical and phenomenal properties would solve the problem with epiphenomenalism (and thus, the most basic aspect of the problem of mind), but they have not been able to take this avenue all the way to a science of consciousness, because cannot see how it is possible to show that phenomenal properties are necessarily connected to something science already mentions in its physical (and/or functional) descriptions. The obstacle they encounter comes from the epistemological approach to philosophy, which contemporary naturalists have inherited, for in this case, ontology as mere realism makes it seem that properties are more basic than substances. Let us see how they fail to find any way to demonstrate a necessary connection between physical and phenomenal properties before we compare epistemological to ontological philosophy.

Necessity in Epistemological Philosophy. Contemporary analytic philosophy offers various ways in which a necessary connection might be established. Let us consider them.

A priori necessity. The original form of necessary truth in contemporary Anglo-American analytic philosophy was analytic truth, or propositions that are true by virtue of the meanings of the terms involved. That would bean a priori connection between physical and phenomenal properties, but it is not a possible foundation for a science of consciousness, for the inability to see an intelligible connection between them is the very problem of consciousness. What we mean by "phenomenal properties" is so different from what we mean by "physical properties" (or by "functional properties," for that matter) that it seems almost absurd even to compare them. That makes it easy to conceive of possible worlds that are physically like our own, but which lack phenomenal properties altogether. That is, there could be a world of zombies, or beings that are physically and functionally indistinguishable form us except for not being conscious. It is also possible to conceive of worlds with phenomenal properties but no physical properties, for that is the view that was defended in modern philosophy as idealism. Hence, no necessary connection can be established a priori.

Causal necessity. Any necessary connection between physical and phenomenal properties must, therefore, be a posteriori. It must be something we can somehow discover about the world from experience. But it cannot be a mere causal necessity of the sort that laws of nature are supposed to have. That sort of necessity would reduce either to causal emergentism or to epiphenomenalism, depending on which causal connections phenomenal properties were supposed to have (that is, being effects of physical properties that are also causes of them, or else being effects that are not causes). It is their inadequacy that forces naturalists to look for a metaphysically necessary connection.

Theoretical identification. The more popular model for discovering necessary connections is theoretical identification in science, such as the discovery that water is identical to masses of H₂O molecules. Thus, just as the solidity of ice was discovered to be identical to the stability of the crystal structure formed by weak hydrogen bonds among adjacent H₂O molecules when their kinetic energy fall below a certain point, so phenomenal properties might turn out to be identical to physical properties of some other kind.

However, physical and phenomenal properties cannot be related in this way, because theoretical identification is a necessary connection. As Kripke(1980) showed, in order for two (rigidly designated) properties to be identical, it must be impossible to conceive one without the other. For example, if the solidity of ice is identical to a certain kind of crystalline structure of H₂O in the actual world, then the identity must hold in any possible world where either exists. It is not, however, impossible to conceive of worlds in which beings physically and functionally like us lack phenomenal properties altogether. No scientific theory can identify the two kinds of properties, and so a world of zombies is still possible.

Supervenience. If the reduction involved in theoretical identification does not provide an avenue to a science of consciousness, science does not offer many other models for showing a necessary connection between physical and phenomenal properties. One possibility is supervenience, which is a weaker relation than the complete reduction involved in the theoretical identification of apparently different physical properties. What has forced philosophers to recognize supervenience is the existence of functional properties. Though a functional property may be identical to certain physical properties in particular cases or classes of cases, there are many other ways that the same functional property can be realized by physical properties and, thus, no general identity between properties at the two levels. For example, there are many kinds of physical mechanisms that can function as clocks. And physical properties that do are said to "realize" a clock. But supervenience cannot be how phenomenal properties are related to physical properties, for that would require phenomenal properties to be identical to physical properties in particular cases, and that is what does not seem to be the case. Thus, a zombie world still seems possible.

A process of elimination leads to the conclusions that, if there is a metaphysically necessary connection between physical and phenomenal properties that can be discovered by experience, it must a new kind of relationship, not previously recognized by science. That is what ontological philosophy offers, and though it is beyond the reach of epistemological philosophy, David Charlmers comes close.

Chalmers (1996, p. 135) considers the possibility that "there are properties essential to the physical constitution of the world that are not accessible to physical investigation." The existence of such intrinsic properties is plausible to him, because all the properties mentioned by physics are basically relational, characterizing entities by their causal connections and other relations to one another. Even physical properties that seem to be inherent in the objects that have them, such as mass, energy, spin, and charge, are measured by the causal relations they have to one another. Thus, whatever has physical properties could also have an intrinsic nature.

However, Chalmers has no way to understand how they might be related to physical properties, because he does not think of substances as anything more than the properties they have. That makes properties ontologically basic, and so he tries to describe the relationship by saying that intrinsic properties might " ‘realize’ the extrinsic physical properties, and that the laws connecting them might realize physical laws" (155). And describing the significance of discovering some such relationship, he says that, if intrinsic properties were "constitutive of physical properties" (136), then even though a zombie world may seem to be physically identical to ours, it would actually be different physically, for it would lack some "inaccessible essential properties, which are also the properties that guarantee consciousness" (135). This is the view of phenomenal properties to which Chalmers himself inclines (153-156), though it has also been suggested by others.vi

As Chalmers recognizes, however, to suggest that intrinsic properties are a special kind of phenomenal (or proto-phenomenal) property underling all physical (and functional) properties is not to show that there is a necessary connection between intrinsic and physical properties. It is merely to point to a possibility. Chalmers (135) rightly calls it "speculative metaphysics." Though it may be coherent, it is no more than speculation, because without the concept of substance to explain the nature of properties, it is just a vague possibility. And since nothing makes it inconceivable that a world physically like our own would lack intrinsic properties, this view reduces to property dualism — a point that Chalmers makes by invoking Kripke’s metaphor: "After ensuring that a world identical to ours from the standpoint of out physical theories, God has to expend further effort to make that world identical to ours across the board" (136). Zombies are still possible.vii

Metaphysical Necessity in Ontological Philosophy. What keeps epistemological philosophy from discovering a necessary relationship between physical and phenomenal properties that would found an empirical science of consciousness is the implicit assumption that properties are basic. What enables ontological philosophy to show that phenomenal properties are an essential part of the natural world investigated by science is reducing properties to substances. Physical properties, as we have seen, characterize the extrinsic essential natures of all forms of material substances, and if phenomenal properties characterize the intrinsic essential nature of some form of matter that helps constitute the conscious subject, phenomenal and physical properties would be related as intrinsic and extrinsic aspects of the essential natures of the substances constituting the world. That relationship does seem to be metaphysically necessary in the sense relevant in this debate, though in our terms it is an ontologically necessary truth, since the necessity of its truth comes from its being an implication of the ontology we have found to be true on empirical grounds.

Metaphysically necessary truths are understood as holding in every possible physical world, and the connection proposed by ontological philosophy is necessary in that sense, for it would hold in any possible physical world in which the basic laws of physics are descriptions of how elementary material substances move and interact. Their basically relational nature indicates that physical properties characterize the extrinsic essential natures of those substances. But since substances cannot have such properties unless they have some way of existing apart from the relations, they must also have an intrinsic essential nature. Thus, Zombies would be impossible. Any being with all the same physical (and functional) properties would necessarily also have intrinsic properties.

To use Kripke’s (1980, 153-4) vivid image, God would not have to go back and tack on intrinsic properties after he had created the physical world, for if God had created the world by combining many material substances in the first place, those substances would already have intrinsic natures of some kind or other. In fact, it would not be possible for God to create a physical world out of multiple substance without intrinsic properties, even if he wanted to.

This is not to say, however, that there is no possible physical world without intrinsic properties. It is possible for a world to have all the same physical (and functional) properties as our own and yet to lack intrinsic properties.

That would be the case, for example, in a physical world that is not constituted by substances at all, as the empiricists’ so-called "bundle theory" of substances would have it. (That is, however, just the form of idealism that one finds when one looks in empiricism for a theory of what exists.)

Even if the physical world must be constituted by substances of some kind in order to exist independently, it could lack intrinsic properties, for it could be constituted by substances that are mere substrata for physical properties (assuming that it is coherent to suppose there can be substances without any inherent properties at all).

Nor would intrinsic properties be needed if the world were constituted by a single substance in which particular properties have spatiotemporal locations.

The necessity of the relationship between intrinsic and extrinsic properties depends, in other words, on an ontological assumption that is not itself necessary, namely, that the world is constituted by many particular substances existing together in some way. There was no such condition on the kind of metaphysical necessity that Kripke discussed, for he was considering only the possibility of properties being identical. That is, if phenomenal and physical properties were identical, there would be no possible physical world without phenomenal properties. But the way in which ontological philosophy demonstrates a metaphysically necessary connection does not come from discovering the identity of two apparently different properties. It comes from discovering that material substances must have two aspects to the essential aspect of the nature as substances. That is, it depends on a theory about the nature of the substances constituting the world that can be justified empirically. (As we have seen, the foundation of ontological philosophy is established by accepting naturalism, taking ontology to be explanatory, and using the empirical method to decide which possible ontological explanation is true.)

Kripke's model for identifying properties with one another comes from discoveries in science that physical properties picked out on the macro-level (such as the solidity of ice) are identical to physical properties picked out on the micro-level (such as the hydrogen bonds among H₂O molecules under certain temperature and pressure conditions).

Ontological philosophy, by contrast, discovers how properties characterizing one aspect of the essential nature of substances (their extrinsic essential nature) are related to another aspect of the essential nature that such substances must have (their intrinsic essential nature). The nature of material substances is what connects them.

Moreover, this ontological explanation of properties is what realists about physics would have to accept, if they took up the ontological issue about their nature at all, for the assumption that there are substances whose aspects are properties is certainly more plausible than any of the alternative theories about substances: the bundle theory, the substratum theory, or the assumption that the whole world is a single substance. And if physical properties are simply the extrinsic essential aspects of the various material substances making up the actual world, naturalists will come to recognize that every possible physical world is made of multiple substances and, hence, that material substances have intrinsic properties in every possible physical world.

This ontological explanation of the necessary connection between physical and phenomenal properties is not a priori, but a posteriori, because it is discovered. As Kripke agues, that means that it must be possible for it to appear that there are possible world in which it does not hold. Kripke showed how such an appearance of contingency is caused in the case of theoretical identification. But it is also possible on this ontological explanation of phenomenal properties to explain how it is possible for it to appear that there are possible worlds in which this ontologically connection does not hold. The illusion of contingency about their relationship comes from failing to recognize that the physical world is constituted by multiple substances and seeing how properties are reducible to them. That is why Chalmers dismisses the belief in intrinsic properties as mere speculation.viii

Relative to a necessary connection established by the identity of properties, the connection established by this ontological argument for its necessity is limited. From the ontological necessity of the connection between intrinsic and extrinsic essential natures of substances it does not follow that there is a ontologically necessary connection between phenomenal and physical properties, not even if phenomenal properties are a kind of intrinsic essential nature of certain substances in our world. Since intrinsic and extrinsic properties characterize different aspects of the essential aspect of substances, it is conceivable that in another possible physical world made of multiple substances, substances would have the same physical properties as ours, and yet have different kinds of intrinsic properties. That is, different worlds could be constituted by different kinds of material substances.

Thus, beings that are physically similar to us in another world constituted by multiple substances might have phenomenal properties with, for example, an inverted spectrum of color qualia. Or they might have more radically different kinds of intrinsic natures. All that is ontologically necessary is that beings like us physically in any possible world made of substances have intrinsic natures of some kind. Though a zombie world is not ontologically possible, an inverted spectrum world is.

Despite this limit to what is necessarily true, however, it is still possible to found a science of consciousness on this ontological explanation of properties, for it implies that, in any possible physical world made of the same kinds of substances as those constituting our world, there are no beings physically and functionally like us that do not also have phenomenal properties like ours. That is enough to found a science of consciousness, because our science is about the actual world. It would be gratuitous to hold that physically indistinguishable material substances in the actual world are different kinds of substances in this sense, especially since they are convertible into one another. Thus, the kinds of phenomenal properties on which one reflects will be the same as those on which other subjects reflect, if the relevant physical properties in the brain are the same.

This ontological explanation of phenomenal properties also explains how they are objects of knowledge. It phenomenal properties are the intrinsic essential nature of some form of matter making up conscious subjects, we can explain why there is something more for Mary to learn about perception when she leaves the black and white neurophysiology laboratory in which she has spent her life and finally sees something red. When she sees something red, the process she has been studying all her life is for the first time embodied in her. Some bit of matter that helps constitute Mary herself has an intrinsic essential nature of a kind whose extrinsic essential nature has been one of the objects of her study. Thus, Mary learns what it is like to be a certain bit of the matter involved in that process.

The property that Mary discovers is, however, an epiphenomenal property on this theory. If phenomenal properties are kinds of intrinsic properties, they are never the efficient cause of anything that happens in the world. The efficient causes are all properties characterizing the extrinsic essential natures of substances, and since they determine what happens, they determine the kinds of bits of matter that exist and, thereby, all the intrinsic properties in the world. But phenomenal properties are not mere "nomological danglers," because intrinsic properties earn their claim to reality for natural science by being necessary aspects of the same substances whose extrinsic essential natures are physical properties.ix

Finally, this ontological reduction of properties also solves Nagel’s problem about the relationship between the "view from nowhere" and the subjective aspect of experience, or "what it is like." By the "view from nowhere," Nagel means the scientific view of the natural world, and if this ontological interpretation of physics is correct, that is the view of the world as being made up of material substances related spatially as parts of the same world. The problem, as Nagel sees it, is that the scientific view leaves out the subjective aspect of experience.

That problem is solved, however, if the world is made up of substances in the sense assumed here, for the subjective aspect of experience turns out to be the intrinsic aspect of the essential nature of certain elementary material substances making up the subject as an organism in nature. What is left out of the "view from nowhere" is not the existence of phenomenal properties, but only their nature. To know their nature, it is necessary to be the substances making up the subject, because what it is like for the subject is the kind of intrinsic essential nature of the relevant bit of matter.

It is still necessary, however, to explain another aspect of the nature of consciousness, namely, its unity, or why so many different kinds of qualia all appear to the same subject and that same time in perception. That is explained in Change: Unity of Consciousness. But that depends on the implication of spatiomaterialism for science, and before taking up science, we must explain why mathematics is true.

Relations

Having considered the properties that substances have in a spatiomaterial world, the next step in demonstrating necessary truths about the world from these ontological assumptions is to determine the kinds of relations that substances have in the world. Relations are different from properties only in that relations hold of (or are true of) more than one substance at once. Thus, relations will be explained ontologically as aspects that hold of more than one substance, just as properties were explained as aspects of substances taken separately. In short, relations are aspects of the world.

It is because of how substances exist together as a world that there are relational aspects of substances. But relations have been introduced in two different ways. The relations among points (that is, the parts of space) are part of the essential nature of space as postulated by this ontology. And there are relations among bits of matter, because each coincides with some part of space or other. (Spatial relations among bits of matter is one of the basic aspect of the natural world that was used as evidence for spatiomaterialism.) Both kinds of relations are part of our ontology, and both will be used to explain other kinds of relations.

Ontological philosophy proves that propositions about relations are true by deriving them from spatiomaterialism. That is, it shows how the relations are constituted by its basic substances, space and matter, given their essential natures and their basic relationship as parts of the same world. Propositions that follow from the best ontological explanation of the natural world are ontologically necessary and, thus, prior to what we know about what actually happens in the world from experience . That is what it means to say that they are "necessary truths," according to ontological philosophy.

These ontologically necessary propositions about the basic relations in a spatiomaterial world include what is usually called mathematics. That is, the basic relations that hold among points (or that can hold among bits of matter at any moment) are, as we shall see, the subject matter of mathematics. There are other ontologically necessary relations in the world, such as those that derive from substances being in time and from further aspects of the essential natures of matter and space. They are merely complications of these basic relations, which will be taken up in the next chapter, Change, which is the subject matter of science.

The ontological explanation of the truth of mathematics and science involves a different set of necessary truths from those already discussed. Unlike the truths about the intrinsic and extrinsic essential natures of substances, these further truths depend on substantivalism about space. The relations among points are part of the essential nature of space. Nor would there be any relations among bits of matter without space to help constitute them.

Explaining relations as aspects of a world constituted by space and matter is straightforward enough, but it is not the traditional way of explaining the truth of mathematics. Epistemological philosophy takes relations to be objects of knowledge, and obstacles to explaining how the basic relations are known to give rise to philosophical problems about the nature of mathematical truth. But the critique of epistemological philosophy is a consequence of ontological philosophy, and so let us begin by considering what can be said about relations as aspects of a spatiomaterial world.

Relations as aspects of substances. In a spatiomaterial world, the relations that hold among particular substances are of two kinds, the relations that hold among points (or parts of space) as part of the essential nature of space, and the relations that hold among bits of matter because each coincides with some part of space. Since the ontological foundation of geometry is space, let us consider what holds simply because of its nature before we see what that implies about the relations among bits of matter contained by space. That will put us in a position to take up the ontological explanation of arithmetic.

Geometry. Geometry describes the structure of space. Space, as we have assumed, is made up of many particular substances whose essential natures include their being related to one another in the way described by three-dimensional (Euclidean) geometry.

The parts of space are particular substances, according to spatiomaterialism, but in geometry, they are called points. Points are identified by their locations in space, since that is how they differ from one another, and they are recognized to be simple, that is, without length, width, breadth, or any possibility of being divided into parts.

The propositions of geometry include the following: Any two points determines a straight line, where a straight line is the path of the shortest distance between them. Any straight line can be extended continuously in a straight line. A straight line and any point not on it determines a plane. Intersecting lines have only one point in common, and when the angles determined by them are equal, the angles are "right angles" and the lines are perpendicular. Through any point, there are exactly three mutually perpendicular straight lines. There is a metric to the distances between points, so that things equal to the same thing are also equal to one another. And so on . . . There is no need to state all the propositions of geometry here, since they are well known.

Since geometry has been used to help define the essential nature of one of the two basic substances postulated by spatiomaterialism, ontological philosophy can explain why geometry is true of the parts of space by the correspondence between geometrical propositions and space as a substance. Those propositions describe an order among the parts of space, and since space is homogeneous, the order is universal and holds in every region. Or as we assumed (provisionally) in the foundation, each part of space has the same kinds of relations to all the other parts of space as every other part of space has to parts others than itself. But it is relevant to notice that explaining the truth of geometry by its correspondence to space does not depend on geometry being stated as an axiom system.

Geometry as an axiom system. The propositions of geometry can be stated as a system in which some are treated as assumptions, and all the rest are all deduced from them (and definitions of terms introduced to simplify the statement of geometrical propositions). The former propositions are called "axioms," and the latter are called "theorems." This way of organizing geometrical propositions was discovered by the ancient Greeks. It was worked out in some detail by Euclid. It aims at an optimal arrangement among the proposition in which some of the simplest and most intuitive propositions are singled out and used to generate all the rest, that is, producing the most in the way of consequences using the least in the way of premises. Geometry lends itself to axiomatization because it describes a simple structure that contains implicitly many complex relations. The relations among the parts of space is a kind of order that makes the whole uniquely simple, and when the axioms describe certain basic aspects of that structure, it is possible to combine those relations in ways that describe all the other relations that must also hold among points, lines, angles, and the like. Such constructions from simpler truths are the derivation of theorems in geometry.

The significance of this deductive arrangement among the propositions of geometry has long been understood epistemologically, that is, as a way of knowing that geometrical propositions are true. Deductive inferences preserve the truth of the premises, and since the axioms of geometry seem to be self-evidently true, it seemed that deriving them from the axioms would prove that they are also true.

This epistemological approach became less attractive, however, as two facts about such axioms systems became known.

The first was that there are different ways of axiomatizing geometry. That is, different geometrical propositions can be used as axioms, and still all the rest follow logically. Thus, there is no necessary order by which some should be taken as implying others.

Second, and more importantly, it became clear that the deductive relationship cannot, by itself, establish any truth about the world. The truth of the theorems depends on the truth of the axioms. But the truth of the axioms cannot be shown within the deductive system. The axioms contain terms which are not defined within the system, or so-called "primitive terms," and thus, the truth of the axioms depends on what those terms refer to. And there are other objects that will make the axioms of geometry true (the set of whole numbers, if nothing else, according to the Löwenheim-Skolem theorem). The deducibility of the theorems from the axioms means that the theorems will be true of whatever objects make the axioms true, but unless the primitive terms in the axioms refer to points and their relations, the theorems of geometry will have nothing to do with the structure of space.

Thus, even though it is possible to come to know that some geometrical propositions are true by deriving them from others that are true, that does not explain why they are true. It merely shows that they are true, if the premises are true. Hence, the truth of both depends on how the premises are true. Ontological philosophy is not bothered by the aforementioned discoveries, because it explains why both kinds of geometrical propositions are true in the same way, that is, by virtue of their correspondence to the world.

If geometry is formulated as an axiom system, then the primitive terms, which are not defined within the system, are taken as referring to the substances it postulates or to aspects of them. The axioms are, therefore, descriptions of the essential nature of one of the two basic substances postulated by spatiomaterialism. But so are the theorems derived from them. They are also descriptions of the essential nature of space. Apart from being entailed by the axioms, what makes the theorems different is that they can be stated without introducing any new basic terms (that is, any terms that are not defined by those used in the axioms).

Euclidean Geometry. In the nineteenth century, however, the deductive view of the truth of geometry suffered another blow, because it was discovered that several axiom systems can be constructed for geometry that are alike in making the most out of the least even though they differ from one another in one of the axioms, the so-called parallel axiom. Euclid’s fifth postulate holds, in effect, that through any point not on a line, one, and only one, parallel line can be drawn in the same plane as the first line. But Lobatchevsky and Bolyai showed that this axiom could be replaced by one holding that more than one line through such a point could be extended infinitely in the plane without intersecting the first line and the resulting geometry would be just as rich in implications. Later Riemann showed that the axiom could be replaced by one holding that there are no parallel lines at all, because any line drawn in the plane through a point not on the same line will intersect with the first line in two points. Both of these new geometries were just as rich in theorems as Euclid’s.

The existence of such non-Euclidean geometries shows that it is possible that space is curved (that is, that geometry is consistent even with carious artificial, new distance functions). But that is not of much consequence to ontological philosophy, for it explains how geometry is true, not by the deducibility of theorems from the axioms of geometry, but rather by the correspondence of the axioms (and, thus, the theorems) to the structure of space.

The correspondence theory of truth does, of course, force us to decide which geometry describes the space we are postulating. And that depends on the nature of the space that we find in the world, for we are following the empirical method in deciding which ontology to believe. That is, we choose the simplest ontological explanation that will explain the basic features of the world. Since the simplest is obviously Euclidean geometry, the space we postulate has a three-dimensional Euclidean structure.

To be sure, since it is an empirical claim, it could turn out that space is not Euclidean. In that case, ontological philosophy would have to start over again with non-Euclidean space of some kind — or else give up spatiomaterialism and go back to epistemological philosophy. But as it turns out, there is no good reason to doubt that space is Euclidean.

What has led naturalists to give up Euclidean space is Einsteinian relativity. Einstein’s general theory of relativity holds that spacetime is curved, and that means that it is not Euclidean. But the curvature of spacetime is quite a different thing from the curvature of space as a substance enduring through time, and as we have promised, spatiomaterialism offers a perfectly intelligible interpretation of what Einstein’s general theory calls "curved spacetime" on the assumption that substantival space is Euclidean. That removes any empirical reason for doubting that space is Euclidean, and thus, we are free to believe the simplest geometry that explains the categorical features of what we find in the world.

What geometry corresponds to. Geometry holds of space in a spatiomaterial world, because the space it postulates is a substance whose essential nature is defined as making geometry true of it. The relations among points, that is, the simplest parts of space, are geometrical. But given how we explain the spatial relations among bits of matter, geometry also most hold of them (except for limitations that may be imposed by bits of matter having a finite sizes in space), because they coincide with parts of space. Thus, the propositions of geometry are true not only of the relations among parts of space, but also of the relations among bits of matter.

In both cases, geometry is ontologically necessary, because it is part of the ontology that we are taking to describe the basic nature of existence. That means that it is prior to what is known about what happen in the world by experience, and that is the sense in which ontology if prior to science and other ordinary ways of knowing about the world.

However, this proof the the ontological necessity of geometry involves a genuine ontological explanation only when its propositions are taken as applying to bits of matter. In that case, they describe facts about the world that depend on both ontological causes, space and matter. There is no genuine ontological explanation of why geometry holds of space itself, because its geometrical nature is what is assumed about just one of the basic substances being used as an ontological cause.

Arithmetic. Besides the relations among points and bits of matter that describe the structure of space, bits of matter and points have a more abstract relationship to one another. They are all parts of a single world in way that allows them to be picked out individually and, thus, to be grouped together. Space is also an ontological cause of this more abstract relationship, for it comes from particular substances having spatial relations that all fit together geometrically. Thus, arithmetic is no less ontologically necessary than the relations that make geometry true.

Arithmetic is, basically, the theory of numbers. The basic numbers are whole numbers, or integers, and arithmetic includes the laws governing their addition, multiplication, subtraction and division. Arithmetic can be taken broadly as including all the propositions about the numbers (except those that have to do with what numbers refer to and how propositions about them are true).

Given the arithmetic of whole numbers, it is possible to construct rational numbers, negative numbers, irrational numbers, and complex numbers and to show that these numbers also obey the laws of addition, multiplication, subtraction, and division. With the use of set theory, transfinite number can also be introduced, though special laws govern operations on them. Taken broadly, therefore, arithmetic includes algebra, the calculus, and analysis.

Even geometry can be included, for its propositions can be generated by way of analytic geometry, or the "algebra of geometry," as Descartes showed. The contemporary attitude is to take arithmetic as more basic than geometry, though that is to reverse the ancient Greek assumption.

Set theory. It is possible to give an ontological explanation of the truth of all these propositions at once, because they can all be derived from set theory. Set theory provides the foundation that mathematicians currently use to prove the truth of arithmetical propositions, taken broadly. But there are various ways of axiomatizing set theory, just as there are for geometry. The most widely used by mathematicians is the Zermelo-Fraenkel system, and its axioms will be used here to show how the truth of arithmetic (and mathematics generally) can be explained ontologically. (A similar argument could be constructed for other axiomatizations of set theory.)

Set theory is a formal system in which the axioms are simply assumed to be true. Though its axioms describe the nature of sets, "set" is a primitive term, and so the axioms are an implicit definition of that term. Thus, if we can show that the substances that constitute the spatiomaterial world satisfy the axioms of set theory, that will show that all the propositions of arithmetic are true of them. Furthermore, since nothing exists in a spatiomaterial world but those substances, it will also show that this interpretation of set theory includes all possible interpretations of its axioms, and thus, that it includes all the ways that set theory can be true by virtue of corresponding to the world. Thus, this is, in effect, to derive the truth of mathematics from the spatiomaterialist ontology, which shows that mathematics is a necessary truth of ontological philosophy.

Let us consider, therefore, whether the substances in a spatiomaterial world satisfy the axioms of Zermelo-Fraenkel set theory.

Axiom 1. The first axiom defines "sets," in effect, by holding that two sets are identical when they have the same members. To explain its truth ontologically, we must say what the members of sets are and what the sets themselves are.

Sets can be members of sets, but unless there is something else the most basic sets are sets of, only the empty set can exist. Set theory says nothing about the nature of the ultimate members of sets except to assume that they are all distinct and can be distinguished from one another. But in a spatiomaterial world, nothing exists at any moment except all the parts of space and all the bits of matter, which it contains. Hence, those substances and what they constitute are the only possible ultimate members of sets that exist wholly at any moment. (We will see how arithmetic can be extended to cover different moments in time in Change.) Particular points in space can be picked out by their locations, and so can particular lines, figures, and other geometrical constructs, since they are constituted by such points. Likewise, let us assume that bits of matter can also be picked out by their locations in space, though we will not explain the sense in which it is true until we take up the concrete nature of matter (in Change). And if ordinary material objects are constituted by elementary bits of matter and parts of space, as spatiomaterialism holds, they can be picked out in a similar way. Indeed, any collection of points in space and/or bits of matter can be picked out as an individual in such a way. These are all the substances, elementary and compound, that can exist at any moment in a spatiomaterial world, and thus, they include all possible ultimate members of sets in such a world.

The sets of such members are, however, distinct from the substances, which are their ultimate members, and in order to explain ontologically how the axioms of set theory are true, there must also be something to which the term "set" refers. What explains the existence of sets in a spatiomaterial world is the fact that all its substances have spatial relations to one another. That is the aspect of the world that makes it possible to pick our particular substances and group them together. Since their possibility is entailed by the essential nature of a spatiomaterialist world, every possible set actually exists as an a distinct aspect of the world.

To be sure, sets would not be recognized to exist without rational beings like us to pick out their members and actually group them together. And we shall see how rational beings (with the spatiotemporal and rational imagination required to construct such sets) come to exist in a spatiomaterial world. But rational subjects are not essential to the existence of sets, since sets are aspects of the world (though I may refer to sets by saying that rational beings pick individuals out and group them together).

Substances may be grouped together in many different ways, by using various properties to define them, but every such class can, in principle, be constructed by the spatial relations of the substances making it up. (They must have spatial relations, since every substance is constituted by a set of basic substances, according to ontological philosophy.) Spatial relations make it possible not only to pick out each substance as distinct from all the rest, but also to group any substances together. Space is a whole of which they are all already parts, and being parts of it, substances can be parts of lesser wholes.

To be sure, merely being parts of the same world also makes them part of a single whole. But that does not make it possible to group them together, because if "the world" is defined as merely all the substances that exist, it would not even be possible to distinguish among particular substances (of the same kind), much less to relate some of them to one another in a way that others are not related. But having spatial relations means that each substance has a unique relationship to all the others and, at the same time, that each is part of a single whole, three dimensional space with them. (Though a bit of matter and the part of space containing it have the same spatial relations to every other substance in the world, they can be distinguished from one another by the kind of substances they are.)

Thus, space is an ontological cause of every set, for it is the wholeness of space that explains the existence of sets. Thus, groups constructed by grouping substances (elementary or composite) together can be taken as the basic sets of Zermelo-Frankel set theory.

The first axiom of Zermelo-Fraenkel set theory holds that two sets are identical if they have the same members. It is true of sets in a spatiomaterial world, given this ontological interpretation of sets and their ultimate members. It is true of the basic sets, because the substances that wind up together in a set do not depend on how they are grouped together, but on which substances they are, for that is the aspect of the world that constitutes the existence of the set. Sets with the same members will be constituted by the same substances. And it holds of sets of sets, because if sets are constructed by grouping substances in this way, sets of sets are just groups of groups formed in this way, and two groups of the same groups will be constituted by the same groups of substances. There is no ontological difference between the two sets.

Axiom 2. The second axiom holds that the empty set exists. The empty set does exist in a spatiomaterial world in the same sense as any set. The same aspect of the world that makes it possible to group substances together also makes it possible to form a group without any members. Whether or not it has any members, the grouping itself depends on how space makes the world whole, that is, on how space itself is whole and how everything contained by space is related in its three dimensions. That aspect of the world is not constituted by substances taken separately, but by how they exist together as a world, and that aspect is what explains the existence of the empty set.

Axiom 3. The third axiom holds that if x and y are sets, then the unordered pair {x,y} is a set. That is to say that sets can be members of sets as well as basic substances, and the truth of this axiom has already been explained.

Sets exist in the sense that spatial relations allow substances to be grouped in all possible ways. But sets that exist in that sense can themselves be grouped in a similar way into groups. For the same reason, it is possible to group sets of sets into sets, and sets of sets of sets into sets, and so on.

Axiom 4. The fourth axiom holds that the union of a set of sets is a set, that is, that a set can be formed from all the distinct substances that are members of at least one set included in the set of sets. That axiom is true in a spatiomaterial world, because sets are just groups of substances. Any substance can be picked out by its spatial relations. And if a substance is a member of more than one of the member sets, it will not become two substances in the union of the sets, because its identity with a substance in the other sets can be determined by its spatial relations.

Axiom 5. The fifth axiom holds that the infinite set exists, including transfinite cardinals. The obstacle to taking the axiom of infinity to be a truth about the natural world has been doubts about the bits of matter in the world being infinite in number. Even if spatiomaterialism did not (yet) take a stance on that issue, it would entail the existence of infinite sets, including transfinite cardinals, because it takes space as well as matter to be a substance.

Space may not be infinite in extent, but since any finite line is infinitely divisible, there are infinite sets of points (for example, the points determined by cutting a line in half, cutting the half-line in half, cutting the quarter-line in half, etc.). Such sets are denumerably infinite, because they can be put in a one-to-one relation with whole numbers. And if the world is infinite, the bits of matter in the world can also be put in one-to-one relations with the whole numbers.

But substantivalism about space also entails the existence of transfinite sets of substances, for the number of points on a finite line is indenumerably infinite.

Axiom 6. The sixth axiom of Zermelo-Frankel set theory is that any property that can be formalized in the language of the theory can be used to define a set. The truth of this axiom is entailed by this ontological explanation of the world, because properties are aspects of substances and all properties are explained by showing how they are constituted by substances. Since properties can all be explained by the substances whose aspects they are, it holds for all the properties that can be formalized in the language of the theory.

Axiom 7. The seventh axiom holds that, for any set, the power set can be formed; that is, that the collection of all subsets of any given set is a set. This follows from our ontological explanation of the existence of sets, for it implies that all sets that can be formed of the particular substances in the world exist, and that includes all the subsets of any set formed, that is, its power set. (What makes this axiom so important is that the power set is itself a set, and another set can be formed of its subsets, over and over again indefinitely.)

Axiom 8. The eighth axiom is the so-called "axiom of choice," which holds that from any collection of non-empty, non-overlapping sets, a new set can be formed by selecting one member from each set. This axiom is clearly true, if sets are all ultimately made up of substances as members (that is, are complex substances), because substances exist.

Despite being used in many mathematical proofs, this axiom has not been considered self-evident, because there seems to be no way to assure that it is possible to pick out a particular member of every set. However, it is always possible, given the ontological explanation of the truth of this axiom. Since the ultimate members of every set are points in space, bits of matter, or determinate combinations of basic substances, it is possible to pick out a specific member of each set by its spatial relations. For example, select the particular substance from each set which is closest to a given point, or in cases of ties, the first in an ordered set of directions in three dimensions from a given point.

Axiom 9. The ninth axiom holds that no set is a member of itself. This axiom avoids certain paradoxes that can arise from taking sets to be members of themselves, for example, Russell’s paradox about whether the set of sets that are not members of themselves is a member of itself. (If it is not a member of itself, it must be a member of the set; but if it is a member to the set as defined, it is a member of itself.) But this is not just a device to avoid paradoxes. It is a fact about sets, if sets are formed by grouping substances or groups ultimately made up of substances together, because it is not possible to include the group one is currently constructing as a member of the group. It does not yet exist, and so rational beings having nothing to group together with the members. Thus, no set is a member of itself.

These are the axioms of Zermelo-Fraenkel set theory, and as we have seen, they are true of a spatiomaterial world, if the ultimate members of sets are substances and sets exist in the sense that substances (and groups of them) can be grouped together. Since deduction preserves the truth of its premises, all of mathematics that can be derived from them (including arithmetic, algebra, the calculus, and analysis) is also true of the natural world, if spatiomaterialism is true. Hence, the truths of arithmetic are not only true, but also ontologically necessary, that is, prior to empirical science.

Solutions of puzzles about set theory. There are further advantages of the ontological explanation of the truth of arithmetic, because it solves several puzzles that have cast doubt on mathematics in the twentieth century.

Totality. It is remarkable that all the truths of arithmetic can be generated by Zermelo-Fraenkel set theory without countenancing the all-inclusive set, that is, the set of all sets. That was required in order to avoid paradoxes, because the all-inclusive set would be a member of itself. But in terms of set theory itself, it is puzzling how sets could exist without all the sets being a set, for they are all parts of the same world.

On this ontological explanation of the truth of set theory, however, there is no puzzle. All the sets do exist together, because they are aspects of a single world, in the sense that they can all be constructed by grouping substances or groups of substances together. That explains how all of the sets can exist without there being a set of all sets. The totality is the world itself. And the set of all sets cannot be formed. As we have seen, it is not possible for a rational subject to group the set he is constructing as a member of the set he is constructing, for it does not yet exist.

Consistency. This ontological explanation of the truth of set theory and the arithmetic theorems that follow from it proves that they are consistent. That is important, because mathematicians want assurance that their deductions will not generate paradoxes, that is, contradictions. In 1931, Kurt Gödel (1906-1978) showed that any formal system that is complex enough to generate the propositions of arithmetic cannot be shown to be consistent on the basis of set theory or logic alone. The inability to prove the consistency of arithmetic has been a source of embarrassment and consternation, because mathematicians now look to formalizations, such as set theory, as the foundation for their mathematical proof.

It is, however, possible to show the consistency of a formal system by giving an interpretation (or model) of it that is assumed to be consistent. That is how the consistency of non-Euclidean geometries was demonstrated. The axioms of Lobachevskian and Riemannian geometry were shown to hold of geometrical objects that were constructed within Euclidean geometry, and that proved that those non-Euclidean geometries were both consistent, because Euclidean geometry was assumed to be consistent.

Although the consistency of arithmetic cannot be shown by logical means, it can be shown ontologically. The reason no one doubted the consistency of Euclidean geometry is that it holds of the structure of the world and the world actually exists. There cannot be any contradiction in propositions that merely describe the nature of something that actually exists. That was an ontological proof of the consistency of Euclidean geometry, and that is the kind of proof that spatiomaterialism gives of the consistency of arithmetic. If set theory is understood as a description of the groups that can be formed of substances in a spatiomaterial world ((by rational beings in that world), then the existence of that world shows that set theory and all the theorems that follow from it are consistent. There can be no paradoxes.

Completeness. Another embarrassment to basing arithmetic on set theory was also contained in Gödel’s 1931 paper, namely, his incompleteness theorem. He showed that there are propositions in arithmetic that cannot be proved. (And what is more, he showed by further, less formal, means that those propositions are true.) That is, Gödel proved by the use of arithmetic that, if any formal system that is complex enough to include arithmetic is consistent, then it is incomplete.

His proof depended on using numbers (Gödel numbers) to represent not only propositions in arithmetic, but also propositions about logical relations among arithmetic propositions. By representing both arithmetic and a formal system for describing logical relations in arithmetic by numbers, Gödel was able to construct a sentence within arithmetic that says, when interpreted, "This sentence is not provable."

Now, is this sentence provable in arithmetic? If it is not provable, it is true. But it must be true, if arithmetic is consistent, because if it were provable, it would be false, and arithmetic would not be consistent. Hence, there is a true statement in arithmetic that cannot be proved.

What Gödel showed was the logical incompleteness of arithmetic and set theory. But that does not necessarily mean that the propositions of arithmetic are not a complete set of truths about the numbers and their properties. That is true only if mathematical truth is taken to be mere provability within set theory (or any other formal system). But that is what ontological philosophy denies. It explains the truth of arithmetic ontologically, that is, as correspondence to the world. And there is no reason to doubt that arithmetic, founded on set theory, is ontologically complete.

That is, Gödel’s incompleteness theory does not give us any reason to believe that there are true arithmetic propositions about the world that are not provable in arithmetic. The statement Gödel constructed, which said, in effect, "This statement is not provable," depended on interpreting the numbers in terms of the symbols used in arithmetic and in a formal system for describing logical relations among propositions in arithmetic. That is not a reference to substances in the world, but a reflective reference to formal systems as they are understood by the rational beings using them, and as we shall see when we explain the nature of reason (in Change: Stage 9), a far more complex ontological explanation is required to spell out the nature of formal systems in terms of the substances constituting the natural world.)

Far from being a puzzle about mathematical truth, therefore, Gödel’s incompleteness theorem is a reason for believing that the truth of mathematics should be explained ontologically. There is no reason to doubt the ontological necessity of mathematical truth, that is, its priority to what is known by empirical science about the world on the basis of experience of what happens there.

Determinacy of reference. Determinacy of reference. A further puzzle was posed by the Löwenheim-Skolem theorem. It holds that a formal system constructed to generate propositions about one kind of mathematical object can always be given another interpretation in which they are true of an entirely different set of objects. For example, any consistent set of axioms constructed to generate all the theorems about real numbers, which are non-denumerable, can be given another interpretation in which they are true of sets which are denumerable, such as the integers. Likewise, axioms designed to derive all the theorems about the whole numbers can be given an interpretation in which they are true of non-denumerable sets. Indeed, every consistent set of axioms has a countable model.

No puzzles are posed by the Löwenheim-Skolem theorem, however, if the truth of mathematics is explained ontologically. Indeed, such a theorem is just what just what should be expected, if mathematics is true because of its correspondence to the world. A formal system, such as set theory, has primitive terms, which are not defined in the system, and what makes it possible to give other interpretations in which those axioms are true is assigning different referents to those primitive terms. But when the truth of arithmetic propositions is explained as correspondence to the world, the primitive terms of the axioms of set theory are introduced as references to substances and the groups that can be formed of substances in a spatiomaterial world, and there is no possibility of another interpretation. All of mathematics that follows from set theory refers to certain aspects of the world.

And we must distinguish between geometry generated as analytic geometry and geometry as explained above, because the correspondence to the world in the latter restricts the interpretation of such terms as "line," "angle," and the like to only certain possible sets in the world.

The usefulness of mathematics in science. This ontological explanation of the truth of arithmetic and geometry may also make it possible to solve other problems (for example, by showing that there is no good reason to believe that the continuum hypothesis is true), but enough has been said to illustrate its significance. There is, however, one final consequence that is worth noting, though it is as much a problem about science as about mathematics.

The assumption that the truth of mathematics comes down to provability within a formal system has made it seem puzzling that mathematics should be so useful in science. Indeed, that is the most unsettling puzzle about mathematics in the view of contemporary philosophers, who take these puzzles as casting doubt on mathematics as the model of true knowledge. But it is not at all puzzling, given this ontological interpretation of the truth of mathematics.

It is not puzzling that mathematics is so useful in science, when its propositions are understood to be about the most basic aspects of the world, namely, how the world is made up of many distinct, particular substances and how, being related to one another spatially, they can be grouped together in all possible ways. Such sets include all the quantitative aspects of substances, from distances and times to masses and forces. Thus, it is hardly surprising that sets in that sense and the ontologically necessary propositions that hold of them because they are substances in a spatiomaterial world are relevant in explaining what happens in the world. Their relevance will become even more clear in Change when we take time into consideration and describe the concrete nature of matter and space. The basic laws of physics describe quantitatively precise regularities about how bits of matter move and interact, and since mathematics holds of the sets picked out for those purposes, there is no wonder that mathematics describes relations that are relevant in those descriptions.

It is not easy for contemporary physicists to see this, however, because the twentieth century revolutions in physics have forced them to abandon the expectation of an intuitive understanding of what their highly mathematical theories are about. Though the intelligibility of scientific theories in terms of spatial imagination was taken for granted in classical physics, it is now generally assumed that it is beyond our grasp. But the ontological explanation of the truth of contemporary physics will show that that is not necessarily the case.

Relations as objects of knowledge. Ontological philosophy explains relations as aspects of the world that exist because of the essential nature of space and how space contains bits of matter at any moment, and correspondence to them explains, as we have seen, how mathematical propositions are true. That means that mathematics is prior to empirical science in the sense of being ontologically necessary. However, necessity in the sense of being certain is what has traditionally been thought to make mathematics different from empirical science. Certainty is what is relevant about mathematics when the project is justifying belief in certain propositions by how they are related to what is known in other ways. Thus, epistemological philosophy approaches mathematical objects as objects of knowledge, rather than as aspects of the world, and it is not obvious that what mathematics is about are the most basic relations that hold in the world.

The problem of mathematical knowledge. When the certainty of mathematics is taken for granted, the problem of mathematical knowledge is to explain how such certainty is possible, that is, why it is more certain than what is known by ordinary experience of what happens in the world.x

It is somewhat misleading to think of the certainty of mathematics only as a problem, for in the beginning, that is what inspired belief in epistemological philosophy. In ancient Greece, mathematics was taken as an example to show the possibility of philosophy as a superior kind of knowledge of the world, one that revealed necessary truths. In the

Meno, for example, Plato describes Socrates as asking a slave boy a series of questions about some lines he draws in the sand which lead the boy to recognize the truth of a special case of Pythagoras’ theorem (that the square built on the diagonal of a square is twice the area of the first square). That put the slave boy in a position to defend what he knew rationally, and Plato used that story to illustrate how knowledge is different from true belief.

Beliefs about whose truth one can be certain are what philosophy pursues out of its love of wisdom, according to Plato. Above the entrance to Plato’s Academy, the first university, it was written that no one should enter who does not know mathematics.

It is hard to overstate how important mathematics has been to the credibility of philosophy’s claim to provide a kind of knowledge of that is superior to our ordinary ways of knowing what happens in the world through experience. But given its role in epistemological philosophy, the issue about how the certainty of mathematical knowledge is possible becomes the issue of how realism is possible.

Theories of mathematical knowledge. To set the stage for considering the received explanations of the certainty of mathematics, let us consider briefly what ontological philosophy implies about the knowledge of mathematics. We will then take up the epistemological theories.

Ontological theories of mathematical knowledge. We have explained why mathematics is true by showing how its propositions correspond to relations as basic aspects of a spatiomaterial world. Geometry corresponds to the structure that space has as (part of) its essential nature as a substance, and that explains why the propositions of geometry hold of bits of matter in space as well as points. Arithmetic holds of the particular substances postulated by spatiomaterialism, because they all have spatial relations to one another, making it possible to pick out particular substances and to group them together in sets. But that does not explain how it is possible for rational beings like us to know that these propositions are true — and to know that they are true in a way that makes them certain in comparison to empirical science and other ordinary ways of knowing about the world.

The short answer is that mathematics is not certain, but merely prior to empirical science. Mathematical propositions are among the necessary truths proved by ontological philosophy. They are ontologically necessary, because they are entailed by the best ontological explanation of the natural world, namely, spatiomaterialism. That is the foundation that ontological philosophy uses to prove that propositions are necessarily true about the world, and mathematical propositions are among them, because they correspond to basic aspects of any spatiomaterial world. But to prove that propositions are ontologically necessary is not necessarily to prove that they are certain, that is, epistemologically necessary. Since spatiomaterialism itself is an empirical truth, the justification of what follows from it is ultimately empirical and, thus, falsifiable by experience. It is nevertheless prior to empirical science, because ontological explanations are prior to efficient-cause explanations. What follows from spatiomaterialism could be false, because spatiomaterialism could be false. But if what follow from it is false, we must give up our otherwise empirically well-founded belief about the basic nature of existence and deny that the world is constituted by its two, opposite kinds of basic substances.

Nevertheless, mathematics seems to be certain. It was not without reason that traditional philosophy took an epistemological approach to necessary truths. And the long answer to the question about why beings like us believe that mathematics is true and believe that it is more certain than science has to do with the nature of reason. Reason is a cognitive capacity that evolves in certain animals, and as we shall see (in Change: Evolutionary stage 9 and following), reason has an ontologically necessary nature which involves two forms of imagination. But it will be easier to explain the received, epistemological philosophies of mathematics if we anticipate that explanation with a brief account of them here.

Animals become rational as they evolve the use of language, and in a world of space and matter in time, it is plausible to suppose that those animals already have a spatial imagination by which they can understand the structure of space.

By "spatial imagination", I mean a brain mechanism (a system of representation in what will be called the "animal behavior guidance system") that uses spatial images of objects and temporal sequences of them to represent objects, their spatial relations to one another in three dimensions, and how their spatial relations change as a result of motion or being manipulated. At its core, it is a memory mechanism that records the locations of objects by lining up images of them in the order they would appear as a result of locomotion in each direction in space, and since "covert locomotion," that is, motor commands for moving the body that are not actually executed, can call up those images in sequence, it serves as a form of imagination that gives animals a nonlinguistic way of thinking about the basic geometrical structure of space and the effects of motion on their relations. (Spatial imagination is this brain mechanism that makes it possible for computers to generate what is called "virtual reality.")

Furthermore, in animals that can manipulate objects, such as primates, spatial imagination also includes an ability to think about the geometrical structures of objects and how they interact when being manipulated. Acts of imagination call up spatial images of objects in sequences that represent the effects of manipulating them in various ways.xi

Spatial imagination gives even nonlinguistic animals an intuitive way of understanding the structure of space, that is, that spatial relations among objects. And as suggested in the last chapter, since such brain activity involves a form of matter whose intrinsic nature registers what is happening throughout the forebrain, spatial imagination is what makes it appear that sensory qualia are located in phenomenal space. That is, its structure is what gives rise to complex phenomenal properties and what we are calling the unity of consciousness. In this context, however, it phenomenal appearance explains the faculty of intuition on which epistemological philosophy typically bases its theory about the nature of reason.

It is not surprising that such a cognitive faculty evolves in a spatiomaterial world, given that animals acquire food by ingesting other objects in space, for it gives them more power over objects in space. Indeed, we shall see that its evolution is inevitable in worlds where evolution can occur at all. But this nonlinguistic understanding of the spatial and temporal aspect of the world is inherited by animals in which language evolves, and in such animals, spatial imagination comes under the control of verbal behavior.

In order to understand a sentence about objects in space, users of language must construct its meaning in imagination. Spatial imagination makes it possible to connect words to particular material objects in space, and thus, learning the meanings of words involves the development of "abstract images," which correspond to properties and relations, or the aspects of objects in space that are called "abstract objects." (As we shall see, they develop in the brain as states that represent many different particular objects of certain kinds indifferently.)

Furthermore, learning to combine such words grammatically involves the development of complex representations, in which properties are related to the objects that have them and states of affairs are represented. Thus, language is a second system of representation. The capacity of language to represent basic aspects of a spatiomaterial world derives therefore, from the spatial imagination of the (mammalian) animal system of representation. (This is the role of what I will later call "natural sentences.")

However, rational imagination, as I will call it, depends on another kind of linguistic representation, in addition to the linguistic representations based on spatial imagination (or "natural sentences') and the representations of spatial imagination itself. The use of language, as we shall see, eventually makes the animals in which it evolves reflective. (This further stage in the evolution of language introduces what I will call "psychological sentences.")

The ability to use more complex sentences enables language-using animals to represent to themselves the (brain) states (such as perceptions, memories, beliefs, desires, and intentions) that occur in the process of perceiving and thinking about the natural world and to think about the roles that such states play in causing behavior and beliefs. Thus, these animals can reflect on the causes of their beliefs and behavior.

But in reflective animals, such reflective (brain) states can themselves be causes of the conclusions they draw about how to behave or what to do, and thus, they have earned a special name. They are called "reasons." In other words, reasons are basically just causes of conclusions that are represented as causes as an essential part of the process of causing such conclusions. Considering how language depends on spatial imagination to connect words to objects in the world, the control that language has over spatial imagination transforms the animal faculty of imagination into rational imagination, a capacity to think about the possible reasons for certain conclusions.

These three elements — the animal's spatial imagination, how it connects linguistic representations to the world, and how language eventually enables the animals in whom it evolves to reflect on the reasons for their beliefs and intentions — are essential to reason, and they explain why it seems that mathematical truths are certain. Spatial imagination is an intuitive way of understanding the structure of space, and thus, if spatial relations among substances are the basic subject matter of mathematics, it is an intuitive understanding of mathematical propositions.

There is, of course, a longer story to be told about how reflection on its operations evolves into explicit knowledge of geometry and arithmetic. But for now, let us simply notice that, as rational beings with such knowledge reflect on the causes of their beliefs, a difference between mathematics and empirical science will inevitably appear. Though it is possible to know the propositions of geometry and arithmetic by perception, in the same way as other facts about nature, it is eventually noticed that they have reasons for believing mathematical propositions that do not depend on perceiving what actually happens in the world. They seem forced to believe, for example, that a straight line is the shortest distance between two points and that two plus three is five by their very understanding of those propositions. Those beliefs seem especially compelling, because those facts about the world are built into the structure of their spatial imagination.

Thus, when epistemological philosophers reflect on how they know that mathematical propositions are true, the first hypothesis is that geometrical objects and numbers are objects of a special kind which are revealed only to rational intuition (or what ontological philosophy explains as the subjective, phenomenal appearance of rational imagination). That is basically Platonism about mathematics.

Given how theorems about geometrical figures and numbers can be derived from axioms, however, another possible hypothesis is that mathematical propositions are a result of logic or reasoning. That leads to forms of anti-realism about mathematics.

In either case, however, there there seem to be reasons for believing mathematical propositions that are sufficient, but which do not depend on perceiving what happens in the natural world. That explains the apparent certainty of mathematics. It can be known in a way that does not seem to be vulnerable to what is learned about the world through perception.

These epistemological theories do not lead to errors in mathematics, because what seems certain in this way actually holds universally in a spatiomaterial world. That is, what spatial imagination corresponds to is the basic aspect of the world in which rational beings find themselves.

It is interesting to notice that, since that basic aspect of the world is its spatial structure, or the aspect of the world that, more than anything else, makes the world whole, mathematics is a way of knowing about the wholeness of the world. And since it is known by subjects who are part of that world, mathematics is the part's knowledge of the basic nature of the whole of which it is part.

This ontological explanation of the apparent certainty of mathematical knowledge is the foundation for its critique of epistemological philosophy of mathematics.

Epistemological theories of mathematical knowledge. The approach of epistemological philosophy is just opposite to ontological philosophy. Instead of starting with ontology and showing that mathematical truths are ontologically necessary, epistemological philosophy starts by reflecting on how we know about the truth of mathematical propositions and tries to show that they are necessary in the sense of being certain, or epistemologically necessary. The basic form of success in epistemological philosophy of mathematics is realism about entities beyond what is known by ordinary experience of the natural world, and as we have seen, the fate of epistemological philosophy is sealed, because its realism involves metaphysical dualism. The problems of metaphysical dualism eventually leads to anti-realism.

As the example of Socrates and the slave boy in the Meno suggests, mathematical knowledge was the original inspiration for philosophy’s claim to have a superior way of knowing about the world. It was the first way philosophy ever claimed to prove there are necessary truths. Since epistemological philosophy began with Plato's use of the certainty of mathematics to illustrate the success of realism, realism in the philosophy of mathematics is now called "Platonism." Given the fate of epistemological philosophy, Platonism eventually leads to anti-realism. But in the case of mathematics, even most anti-realists affirm the certainty of its propositions. There is, however, a form of anti-realism that denies the certainty of mathematics by assimilating it to empirical science, that is, by denying that there is any basic difference between mathematics and science.

A brief account of the history of epistemological philosophy of mathematics follows, and having seen how ontological philosophy can explain why mathematics appears to be certain to those who reflect on how they know it, I will use the ontological theory of reason to show not only what is true and false in the traditional theories of mathematics, but also how the philosophical problems caused by the epistemological approach are solved by ontological philosophy.

Realism: Platonism about mathematics. For philosophers who argue from how we know to what can be known, success comes from showing that we have knowledge of the real existence of entities of some kind beyond a kind of knowledge that is taken for granted, that is, knowledge of reality beyond appearance. In the philosophy of mathematics, realism is called "Platonism," after its founder. But Platonism takes different forms in the ancient and modern worlds.

Ancient Platonism about mathematics. Plato’s explanation of what the slave boy learned from Socrates is that beings like us have a faculty of reason that makes us aware of objects that are fundamentally different from the objects of perception. That is how all genuine knowledge (as opposed to mere belief) was explained by Plato, and it is the model for Platonism in mathematics. Numbers and geometrical objects are part of a reality that Platonists believe lies beyond appearances in natural world.

According to Plato, the Forms in the realm of Being are different from natural objects, which are known by perception (that is, empirical knowledge), because the Forms do not change and never appear differently from what they really are. What enables us to know about them is rational intuition, which Plato repeatedly contrasted to perception, as knowledge to mere belief. But it is the difference in the natures of the objects being cognized that was supposed explain the certainty and necessity of mathematical truths.

Rational intuition of mathematical objects does involve appearances, according to ontological philosophy, for there is a faculty of rational imagination in the brain and its activity has an appearance to the subject by way of phenomenal properties (by generating bits of matter whose intrinsic natures register brain activity). But that is not the appearance of objects that are outside space and time, and the belief that the objects being grasped are Platonic Forms involves an insuperable problem, namely, Platonic ontological dualism.

Mathematical propositions hold of objects found in the natural world, and in order for Platonists to explain how our knowledge of such propositions is certain, they need a way to explain why truths about abstract entities in a realm beyond nature reveal something about objects that exists in nature. The main problem with platonic realism, as Plato himself recognized, is that there is no way to explain how objects outside space and time can have any effect on objects in the natural world.xii

Ontological philosophy avoids the problems of Platonic realism by taking mathematical objects to be aspects of the natural world, rather than abstract entities that exist in a transcendent realm. But it can also explain why they appear to be abstract entities. In both cases, abstract entities are reifications of concepts based on spatial imagination.xiii

Though geometrical structures are always concrete parts of space, they seem to be universal, because space exists everywhere with the same three-dimensional structure. Since reflective subjects with spatial imagination recognize such geometrical structures in many different particulars, it is not surprising that they think of them as universals or abstract entities.

Likewise, though the material objects they count are concrete particular substances existing independently of one another, their spatial relations are what makes it possible for them to be grouped together, and since that makes the results of arithmetic operations the same everywhere, numbers seem to abstract entities.

Modern realism (Platonism) about mathematics. With the rise of modern philosophy, the problems with Platonism about mathematics were transformed, but not solved. Plato was a naive realist about both perception and reason. He believed that the objects of both forms of intuition (that is, perception and rational imagination) exist independently of the subject, but are nevertheless immediately present to the subject. The modern period began with the recognition that perception is mediated by appearances (or "ideas’) that are part of the mind, and that meant that rational intuition is likewise just another kind of appearance in the mind (what Descartes called clear and distinct ideas). That eliminated the problems caused by Plato's attempt to explain the relationship between the objects of perception and the objects of reason as the relationship between Forms in a realm of Being and visible objects in the realm of Becoming. But modern philosophers were still Platonists, in effect, because they believed that what makes knowledge of mathematics certain, in contrast to empirical knowledge, is that it is about abstract objects that exist independently of both the subject and the natural world. But instead of existing in a realm of Being, mathematical objects were taken to exist as ideas in the mind of God. In short, as an offspring of the marriage of Platonism and Christianity in the medieval period, the modern era had inherited a rationalistic theology in which God played the role of the realm of Being.

Modern philosophy still had to explain, however, why mathematics is true of the natural world. Indeed, the question was even more pressing, because the new science discovered laws of nature that are highly mathematical. Those laws described precise quantitative relationships among properties, such as distance, mass, time, and velocity, and since relations among different quantities of the same property are arithmetical, those physical descriptions required the truth of mathematical propositions.

Modern philosophy had, however, a ready solution, at least, until doubts about theistic supernaturalism late in the eighteenth century, because the objects of mathematics were assumed to be ideas in God’s mind. God created the natural world according to a rational plan, and since God had used mathematics to create a world governed by natural laws, the discovery of those laws was basically seeing into God’s mind. In The Assayer (1610), for example, Galileo described nature as a book that God had written in the language of mathematics. And Descartes used God to prove that our clear and distinct ideas about geometry corresponded to extension, the essential nature of the bodily substance. In other words, it was possible for rational beings to recognize the truth of mathematical propositions, because rationality comes from their being created in God’s image.

Anti-realism about mathematics. The problems of supernaturalism eventually made Platonism in either its ancient or modern form untenable. There is simply no way to prove the existence of entities existing beyond the natural world. But anti-realism about mathematics takes two fundamentally different forms, because mathematics still seems to be certain, even if realism is doubtful.

One form continues to accept the certainty of mathematics and tries to explain how there can be such self-evident truths without having to prove the existence of entities beyond what is given to ordinary experience of the world.

The other form takes the denial of the existence of platonic entities beyond the natural world to mean that mathematics must be about the natural world, and by assimilating mathematics to empirical science, denies that mathematics has the kind of certainty that is taken for granted by realists and other anti-realists.

Anti-realism that affirms the certainty of mathematics. The nineteenth century was a transitional period in the history of mathematics. Not only did the rise of naturalism made Platonism less attractive, but developments in mathematics itself also made it less plausible that mathematics describes the essential nature of a reality beyond the subject, natural or supernatural.

Though Euclidean geometry had once made it seem obvious that one kind of rational certainty somehow reveals the inherent nature of the natural world, the discovery of non-Euclidean geometry cast doubt on that assumption. The certainty of geometry seemed to depend more on the deducibility of theorems from axioms. And recognition that the arguments (about infinity) on which the calculus had been based were logically faulty focused mathematicians on the project of making mathematical proofs more rigorous. Though physics undoubtedly required mathematics for its spectacularly successful descriptions of regularities in the natural world, it was, by the beginning of the twentieth century, plausible to hold that the certainty of mathematics does not come from knowing a special kind of object that exists independently of the subject. Instead, it seemed possible to explain its special certainty as deriving from the nature of the rational subjects themselves.

Various theories of the certainty of mathematical truth have been proposed in the twentieth century, and disputes among them tend to be technical. But a rough sketch of two opposite approaches and their problems will put us in a position to see why naturalists now seem to have little choice but to treat mathematics as a species of empirical, scientific truth. Both of the following views give up the belief in independently existing, abstract entities, and both explain its certainty by holding that it is a kind of truth that is discovered within the mind. And both are just what would be expected of epistemological philosophers, given how ontological philosophy explains the ability of rational beings to know the truth of mathematical propositions. One takes account of the role of spatial imagination and attempts to reduce all of mathematics to objects of rational intuition, and the other takes account of the role of language in expressing those intuitions and attempts to reduce mathematics to logic or the structure of language.

Intuitionism. Intuitionism derives historically from Kant, and it reflects the assumptions of modern philosophy. Kant argued that mathematics is a priori knowledge about the natural world because it describes the structure of the forms of intuition (space and time) in which nature itself is presented in experience. Proofs of mathematical propositions involve the construction of mathematical objects in imagination, and thus, they must conform to the mind’s pure forms of intuition, space and time. But that means that mathematical truth hold necessarily and universally in experience of the natural world, because the two forms of intuition are also conditions of possible experience.

Kant was describing the process by which rational beings do actually come to accept the certainty of mathematical propositions, according to our ontological explanation of reason. The role that Kant ascribed to space and time as forms of intuition in understanding mathematics is explained by spatial imagination, and that accounts for knowledge of geometrical and arithmetical propositions.

The use of a language to control and to reflect on the structure of spatial imagination gives one a nonlinguistic understanding of what is meant by such concepts as "point", "line", "plane", and "sphere," and thus, one can "see" that there is a shortest distance between two points and that a line and a point not on it determines a plane. One can also recognize the truth of simple propositions, such as that exactly three lines intersecting at a point can be mutually perpendicular, that three planes can be mutually perpendicular, and that any closed plane figure with just three internal angles has three sides.

Ontological philosophy confirms Kant's theory of arithmetical knowledge in a similar way. Spatial imagination enable reflective subjects to think about the operations of singling objects out, combining them as groups, adding and subtracting members, and the like, and thus, they can recognize the truth of arithmetic axioms and construct theorems of arithmetic in imagination. That makes it seem that such truths about the world can be known prior to discovering their truth by perception, because what makes arithmetic true is the way in which space makes different bits of matter parts of the same world and that aspect of the world is represented in spatial imagination.

It also seems, in a similar way, that they can know the truth of theorems in other mathematical systems constructed from arithmetic and geometry, such as calculus, prior to discovering their truth by perception.

Though Kant did not develop his constructivist approach to mathematical propositions in much detail, intuitionism was taken up by many mathematicians in the twentieth century (including Henri Poincaré, 1854-1912) and given a detailed defense by L. E. J. Brouwer (1881-1966).

In the end, however, intuitionism was not acceptable to most mathematicians, because the requirement that all mathematical objects be constructed in imagination required giving up too much of mathematics. (Brouwer rejected the axiom of choice, actually infinite sets, Cantor’s transfinite numbers, and any arguments for the existence of mathematical objects based on the law of excluded middle.)

Even if it were possible for intuitionists to construct all of mathematics, however, this way of explaining the certainty of mathematics implies that its truth comes from the structure of thought. Kant believed that nature is just the phenomenal world, which is "in the mind," so to speak, and though he never doubted there is a noumenal world (or things in themselves) beyond the phenomenal world, he denied that mathematical truths hold of it (or them). That may be plausible to Kantians, but it is not plausible to naturalists. Naturalists believe that what exists independently of the subject is a world of material objects with spatial relations that change over time, and intuitionism does not imply that mathematics is true of that world.

Logicism and formalism. The other way of explaining the certainty of mathematics in epistemological philosophy without accepting Platonism tries, in effect, to reduce mathematics to language. Historically, it has taken two main forms, logicism and formalism.

Logicism holds that all of mathematics is derivable from logic. Its philosophical roots are in Leibniz, but it was developed more rigorously by Gottlob Frege (1848-1925) and Bertrand Russell (1872-1970) around the turn of the twentieth century.

It turned out, however, that the laws of logic needed to generate number theory involved several axioms that hardly seemed to be laws of logic at all. They included, for example, the axiom of reducibility (which holds that propositions about higher types, or sets of sets, could be reduced to propositions about first order members of sets), the axiom of infinity (which affirms the existence of infinite sets), and the axiom of choice (which says that from any set of non-empty, non-overlapping sets, it is possible to form a set of one member from each). If one were to insist that these are laws of logic and that they are known by rational intuition of some kind, logicism would be a kind of Platonism in which the laws of logic, rather than the mathematical objects themselves, have an independent existence as abstract objects outside of space and time. But to many, these axioms seemed more doubtful than the propositions about numbers that were derived from them.

"Formalism" is the name of the project pursed by David Hilbert (1862-1943) in order avoid the problems of logicism. He did not believe that mathematics could be reduced to the laws of logic. He held that each branch of mathematics requires its own axioms and rules of inference. But he believed that logicism was on the right track in taking logical entailments to be what explains mathematical truth. Thus, Hilbert set out to prove the certainty of mathematics by reconstructing each branch of mathematics as a formal system with its own axioms, rules of inference, and theorems. But these statements were to be stripped of any meaning outside the formal system and treated as meaningless symbols, mere marks on paper, which were written down in sequence according to strict rules. Each formal system would include all the propositions in some branch of mathematics, and the rigor of these symbolic manipulations was supposed to prove the certainty of its theorems.

The formalists’ explanation of mathematical certainty, however, required systems constructed in this way to be free of contradictions, and so Hilbert saw the main challenge as demonstrating their consistency. For this purpose, he developed a special formal system for describing formal systems, a "metamathematics," which was supposed to be beyond reproach. In the end, however, it was not possible to demonstrate the consistency of arithmetic, or even of set theory, as Gödel showed. (This is the origin of the puzzles encountered by set theory that were solved in the ontological explanation of the truth of arithmetic in Relations: Solutions to puzzles.)

What logicists and formalists are getting at can be understood from our sketch of the nature of rational subjects. They are also epistemological philosophers reflecting on how we know the truth of mathematical propositions. But by contrast to intuitionists, they abstract from spatial imagination and focus on the use of language. They identify brain states by the linguistic representations they involve, and they use logical relations to keep track of the causal roles that brain states play in drawing conclusions about what to believe. By focusing exclusively on the formal relations among brain states identified in that way, whole systems of mathematical proofs can be reconstructed as formal deductive systems. The logical structure of language represents the elements in such reasoning completely enough that there are formal tests of the validity of those inferences, making it seem that their truth can explained by their deducibility from certain axioms and definitions.

Though the validity of deductive relationships in formal systems does afford a certain concept of certainty, it does not explain how mathematics is true. Even logicists complained that formalism cannot account for the truth of the axioms or the usefulness of the definitions that are assumed. But neither do the axioms used in geometry and arithmetic follow from the laws of logic. Indeed, any consistent set of sentences could be used as axioms and definitions, because as far as formal logic is concerned, deductive systems are just rule-governed ways of transforming assumptions as inscriptions that preserve their truth. Formalism has no explanation of why the axioms used in mathematics should be singled out as true. Nor does it explain why they, or the theorems derived from them, should be useful in describing the natural world.

Anti-realism that denies the certainty of mathematics. Applicability to the natural world is, however, as crucial to the nature of mathematics as its apparent certainty, and since neither the intuitionists nor logicists/formalists were able to explain its certainty in a way that would also explain its applicability to nature, naturalists could not help being attracted to the view that mathematical objects are somehow part of the natural world. That would be, like Platonism, a kind of realism about mathematical objects. But since our way of knowing about the natural world is perception, it would be more like scientific realism, for there would be no basic difference between mathematics and empirical science. And it would have to deny the certainty of mathematics.

The view that mathematics is a form of empirical knowledge was first defended by John Stuart Mill in the nineteenth century, but it was renewed in 1983 by Philip Kitcher.xiv Kitcher rejected what he called "apriorism", the belief that the certainty of mathematical knowledge comes from its being epistemologically prior to experience of nature, and proceeded to explain mathematics as a species of scientific knowledge. Kitcher bases knowledge of mathematics on perception, by thinking of arithmetic operations as "idealizations" of publicly observable manipulations of natural objects.xv

The price of explaining how mathematics is true about nature seems to be giving up the belief that it has a certainty that is basically different from natural science. Kitcher explains the appearance of certainty by the extremely general character of the regularities described by mathematical hypotheses. But since there is no essential difference between mathematics and scientific hypotheses, he agrees that they are confirmed in basically the same way.

Ontological philosophy agrees with Kitcher in rejecting apriorism. It also takes mathematics to be a form of empirical knowledge in the end. But the end does not come so quickly as it does for Kitcher, because ontological philosophy recognizes two levels of explanations (ontological-cause explanations and efficient-cause explanations) and, accordingly, two levels of empirical truths (empirical ontology and empirical science). In other words, instead of taking mathematics to be knowledge of very general regularities about what happens in the world, it sees mathematics as knowledge about the most basic (or categorical) features of what exists in the world, namely, how space makes the world whole. That means that mathematics is still prior to empirical science in a philosophically relevant way. But the priority is ontological rather than epistemological.

Furthermore, when this explanation of mathematical truth as ontologically necessary is combined with what ontological philosophy holds about the nature of reason, there is even a sense in which mathematics is epistemologically more certain than empirical science. As we have seen, it holds that mathematical knowledge is not merely a correspondence of linguistic representations to the world, but also involves a correspondence of representations in the brain’s spatial imagination to the world. Thus, unlike Kitcher’s theory, it can explain the role that constructions in imagination play in proving mathematical truths according to intuitionists as well as the role of formal deductive relationships among sentences that logicists and formalists take to be basic.xvi

But as we have seen, what explains the truth of both geometry and arithmetic ontologically are the spatial relations that particular substances have in a spatiomaterial world. Thus, since the rational subject is part of the world, mathematical knowledge involves a relationship between subject and object that is a correspondence between the structure of spatial imagination in a part of the world and the basic structure of the whole world of which he is part. It is within that basic correspondence that rational being discover what happens in the world by perception, and thus, if this is a spatiomaterial world, mathematics is not only ontologically necessary, but epistemologically certain.

Change

The third set of necessary truths entailed by spatiomaterialism has to do with change, and it is by far the largest set, since it includes all of science. Science is the explanation of change by efficient causes, and the range of kinds of changes found in the world means that science includes not only all the branches of natural science (physics, chemistry, biology, and physiology), but also all the social sciences (psychology, sociology, economics, political science, anthropology, and history).

What changes in the natural world are properties and relations of substances, not the basic substances themselves, since substances, as substances, simply endure through time. Properties and relations are aspects of substances constituting the world, and given the essential natures of the basic substances and the basic relationship by which they exist together as a world, there are aspects that can change. That means that some of those changes can be given genuine ontological explanations., And such ontological explanations are important, because they can explain the nature of the necessity about efficient causation..

Some changes in contingent properties can be explained ontologically, because they are simply changes in certain aspects of basic substances as they endure through time. Such ontological explanations can be given only when the possibility of change is entailed by the essential properties of matter and space and how they exist together as a world. For example, the possibility of changes in spatial relations can be explained ontologically.

As we shall see, change in spatial relations is possible, because bits of matter can have different relations at different times without compromising the essential nature of either space or matter and compatibly with their basic relationship as parts of the same world. It can occur by motion, and those same ontological causes entail, as we shall see, that spatial relations can change only by motion.

Efficient cause explanations depend on regularities about change, that is, on so-called "laws of nature." But insofar as such regularities about change are given genuine ontological explanations, the connections they describe between efficient causes and their effects are shown to be ontologically necessary (because they follow from the endurance of the substances through time with the same essential natures). That explains the necessary connection between efficient causes and what they make happen in the world.

Ontological explanation is genuinely explanatory only when substances work together in some way to constitute something more that what is assumed about them. Or to put it negatively, insofar as change has to do with regular changes in the contingent properties that are used to define the essential natures of substances (that is, insofar as the substances have temporally complex, or dispositional, essential properties), there is no genuine ontological explanation of the change, for the change is simply what is assumed by the ontology. Hence, there is no ontological necessity.

Traditional epistemological philosophy, by contrast, does not treat change as an aspect of the substances constituting the world, but rather as an object of knowledge. Science tries to explain what happens in the world by finding efficient causes, and since such efficient-cause explanations presuppose laws of nature, epistemological philosophy takes the goal of science to be the discovery of laws of nature. But that approach to the philosophy of science has encountered problems that remain unsolved.

One main problem of epistemological philosophy of science has been the explanation of the nature of efficient causation itself. Efficient causes are supposed to produce their effects, that is, make it necessary that they occur. But the laws of nature on which science bases such efficient-cause explanations seem to be just descriptions of regularities about how properties and relations that have been observed to change over time. But if they are merely descriptions of observable regularities, there is no explanation of the source of the necessary connection that is supposed to hold between the efficient cause and what it explains. This is basically the problem about causation that Hume discovered.

Since epistemological philosophy of science takes the goal of science to be the discovery of the laws of nature on which efficient-cause explanations are based, it has also encountered a major problem concerning the relationship between the laws discovered by different branches of science. It now seems that the laws (and, thus, the efficient-cause explanations) of the less general sciences cannot be reduced to the laws of more general branches of science and ultimately to the basic laws of physics. That complicates the problem about the nature of efficient causation, because the causal connections described by less general branches of science cannot be explained by physics. But it also makes the relationships among the branches of science problematic.

Though epistemological philosophy of science has not found an adequate solution to either of these problems, we will see how ontological philosophy solves them when we return to the issue of efficient causation after explaining change as an aspect of substances.

Another project of philosophy of science has been to show that what science claims to know about change is genuine knowledge. Since it takes an epistemological approach to philosophy, that is the project of defending realism in some form, and it leads, once again, to anti-realism, or skepticism about science. But we will see how this problem is solved when we trace the course of evolution at the end of this chapter. Indeed, we will see why the problem arises. (See Change: Evolutionary stage 10, the Career of epistemological philosophy.)

Change as an aspect of substances. Existence is one of the two most basic aspects of substance as substance, and as we have seen, there are two aspects to the existential aspect of substance, particularity and temporality. Temporality was not relevant in explaining the truth of mathematics, since spatial relations exist completely at each moment. (Particularity was required to explain the relations among basic substances, since relations depend on how substances exist together as a world). The temporal aspect of the existential aspect of a substance is how substance endures through time, and its consequences are considered in this chapter.

Though we assume that substances have essential natures that do not change as time passes, change is possible, as we have seen, because space and matter have opposite natures and each bit of matter coincides with some part(s) of space or other. But since spatiomaterialism leaves it open which parts of space each bit of matter coincides with, it is ontologically possible for bits of matter to have different locations at different times. Moreover, it is possible for bits of matter to change their locations as time passes, because bits of matter can move. Motion is possible, as we have seen, because the parts of space are connected continuously, just as moments in time. Furthermore, motion makes it possible, as we have also seen, for bits of matter to change by interacting with one another, because if bits of matter can move, the three dimensional geometrical structure of space makes it possible for more than one bit to move to the same (or adjacent) parts of space. When bits of matter have the same or adjacent locations, they can act on one another, thereby changing properties or relations of the bits of matter and parts of space involved.

Their ways of moving and interacting are extrinsic properties of bits of matter. Their intrinsic properties may also change as their extrinsic properties change, though changes in intrinsic aspects of their essential natures do not affect how bits of matter move and interact.

What makes it possible to explain change ontologically, rather than merely assume it, is the essential nature of space, that is, its structure or wholeness. The parts of space are all necessarily connected in three dimensions according to Euclidean geometry (entailing that space is whole), and since space contains all the bits of matter, its nature makes it possible for bits of matter to move and interact with one another. And we will see how space and matter work together to constitute the regularities described by the basic laws of physics. But not only does the basic nature of a spatiomaterial world make change possible and afford an ontological explanation of the laws of physics, it also makes certain kinds of changes impossible and other kinds ontologically necessary. They are the ontologically necessary truths about how change takes place. Unless those regularities hold, the world cannot be constituted by matter and space enduring through time with all the matter contained by space.

There are, however, two basically different kinds of regularities entailed by spatiomaterialism, because space not only constrains how each bit of matter can move and interact in relation to other bits of matter in its neighborhood, but it also connects all the changes they undergo in any region of space.

The ontological constraint on how bits of matter can move and interact in relation to one another entail necessary principles about the kinds of local regularities that can hold. Within those ontologically necessary limits, there are further regularities about change that are contingent. More specific aspects of local regularities depend on the specific kind of matter and space making up the actual world, and thus, they can be known only by further experience of the world. They are the regularities described by the basic laws discovered by physics, and as we shall see, there ways of explaining ontologically why those laws are true.

The way that space connects the changes that happen to different bits of matter in any region imposes global regularities on change. The changes that occur to all the bits of matter in any region must “add up” in a certain way as time passes, because they all coincide with parts of space in the same region and space also endures through time as a substance with a wholeness that connects all of them to one another. Their motion and interaction “add up” in any closed or isolated region of space to global regularities about change, though most of the specific global regularities also depend on the laws of physics that hold only in spatiomaterial worlds like ours.

The wholeness of space can be distinguished from the geometrical structure of space, because the fact that all the parts of space fit together as a whole is just one consequence of its parts having geometrical relations to one another. Thus, we can say that, whereas the local regularities depend on the structure of space as an ontological cause, the global regularities also depend specifically on the wholeness of space as an ontological cause.

Local regularities about change.Regularities about change are local when they are about how each bit of matter moves and acts relative to other bits of matter. This aspect of the world is singled out when we focus on a particular bit(s) of matter and consider how it moves in relation to other bits of matter in its neighborhood or how it interacts with them. There is, however, a difference between necessary principles and contingent laws about local regularities.

There are certain aspects of such changes that hold, regardless of anything further that physics may discover empirically about the essential natures of the matter or space involved, because they are entailed by spatiomaterialism (or the basic nature of matter and space and how space contains matter). They are what I will call “ontologically necessary principles” about local regularities.

Many possible ways of changing are left open by the limits imposed by the necessary principles about local regularities. And bits of matter (and space) can change only in some determinate way, for they are just substances with some specific essential nature or other, entailing that such change is regular in some way. But how they change depends on the specific kind of matter and space of which the actual world is constituted. The regularities about change that depend on the specific nature of matter and space will be called “contingent laws” about local regularities. These contingent laws include all the basic laws of physics.

In what follows, we will see how it is possible to explain the basic laws of physics ontologically. It must be possible to explain them by the specific essential natures of matter and space, if spatiomaterialism is true. The possibility of such an ontological explanation is not very surprising in the case of classical physics (though it has some surprising implications, for example, about the nature of kinetic energy). But the possibility of such an explanation is precisely what is put in doubt by contemporary physics. Showing how relativity theory can be explained ontologically by spatiomaterialism is one of the mortgages that remains to be paid in order to use that ontology as the foundation for this argument demonstrating necessary truths, and as we shall see, quantum mechanics can also be explained ontologically by spatiomaterialism.

Necessary principles about local regularities.Necessary principles about local regularities follow from the basic natures of space and matter as substances enduring through time assuming that each bit of matter coincides with some part of space or other. We have already seen how their essential natures explain the possibility of change by motion and interaction ontologically. The same ontological causes imply that they can change only by local motion and local action.

The principle of local motion.The principle of local motion holds that bits of matter can change their locations as time passes only by moving continuously across the space that separates the starting points and the ending points. That is what I will call “local motion.” What it denies is that bits of matter can ever change their locations by simply disappearing from one location at one moment and appearing somewhere at a distance at the next moment. That is, it denies that bits of matter can “flit about” discontinuously in space from moment to moment.

The reason that “flitting about” is impossible is that it could occur only if one of the three basic assumptions of spatiomaterialism were false, that is, only if space were not a substance, matter were not a substance, or bits of matter did not coincide with parts of space.

Given that the bit of matter is a substance enduring through time, how could it have one location at one moment and another location at a distance from it the very next moment, that is, without moving to the second location? It might be possible if space were not a substance, but a mere relation between bits of matter, for spatial relations could simply be defined as kinds of relations that change discontinuously. That is a possibility for a materialist ontology, which reduces space to relations among bits of matter. But if space is a substance with the essential nature we have assumed and it gives bits of matter spatial relations by how they coincide with different parts of space, then the spatial relation between the first location and the second location depends on the existence of all the other parts of space enduring as substances through time, including all those parts of space in between the two locations. Thus, the only way that the bit of matter could come to have the new spatial relations is by coinciding with a continuous series of parts of space separating the two locations as time passes. That is the only way that bits of matter can change their spatial relations in space, if they get their spatial relations from the relations among the parts of space with which they coincide and the parts of space are all related according to a geometrical structure.

Given, therefore, that space is a substance, how is it possible for bits of matter to flit about discontinuously? It might be possible, if the bit of matter could simply drop out of existence at one moment and come back into existence at the distant location the next. But that would be to deny that the bit of matter is a substance in our sense, for it would not be enduring through time. Its existence would not be continuous, if it dropped out of existence and then came back into existence, even if it came back into existence the very next moment.

Nor can we suppose that the bit of matter simply slipped out of space altogether at one location and slipped back into space at another location, because that would contradict the assumption that bits of matter are contained by space. The basic relationship assumed by spatiomaterialism is that, at the present moment, each bit of matter coincides with some part of space or another. This is what give bits of matter their spatial relations to one another. And since it holds at the present moment, it must have held at all moments in the past and it must hold at all moments in the future, for there is no other way for bits of matter to acquire spatial relations to one another

In a spatiomaterial world, therefore, the only way that bits of matter can change their spatial relations is by local motion, that is, by moving continuously across space. Nothing else is compatible with the assumption that space and matter are substances enduring through time, with all the bits of matter coinciding with parts of space.

And that means that bits of matter move with a finite velocity, since infinite velocity would be equivalent to “flitting about” in space.

The principle of local action.Once again, the same factors that explain the possibility of change by interaction also imply that such change can occur only by local action. Motion makes it possible for bits of matter to come to occupy the same or adjacent locations, and if motion does so, that puts them in a position to act on one another, assuming that matter has a more specific essential nature that includes such powers. On the other hand, if bits of matter are not in the same (or adjacent) locations in space, they coincide with distinct parts of space that are separated by other parts of space, and they cannot affect one another without something traveling across the space between them, for space is the only connection the bits of matter have to one another.

They are also related by being parts of the same world, but we are using “parts of the same world” to mean only that they exist or are a part of everything that exists, and bare existence does not entail any other relations between them.

In order for bits of matter located at a distance from one another to interact, another bit of matter must travel across the space separating the one bit of matter from the other as time passes. The bit of matter may be just the exertion of a force (in which case it is an inter-action, with an opposite force also being exerted, according Newton’s third law of motion). But even if such a force were just a “modification” of relevant parts of space, it would still be a bit of matter, that is, a material substance, and as such, it cannot get from one location to the other without something moving across space as time passes time, or else it would violate the principle of motion.

The principle of local action is not as simple as it sounds, for as we shall see, there are various forms of matter, and some of them coincide with more than one part of space at any given moment. Indeed, one form of matter (forces with infinite range) can, in principle, coincide with all parts of space (albeit not all equally). Such forms of matter can interact with other bits of matter wherever they are located.

There are, however, other forms that are completely outside one another in space (including, as we shall see, some of the rest mass of the material objects that exert forces with infinite range), and the principle of local action does constrain their interactions. These complications will be taken up as we explain the various forms of matter and how they move and interact.

The principle of local action has to do with how bits of matter that are localized in space can act on one another when they are located at a distance from one another, and such “actions” will be defined more fully in explaining how quantum mechanics is true in a spatiomaterial world. But there is another kind of very limited effects that certain forms of matter can have on one another, in addition to such inter-actions, and space is an ontological cause of the same kind of limitation on them. That is, the principle of local action is really just part of a more basic principle, which might be called the “principle of local action or effect.”

These peculiar effects that bits of matter of certain kind can have on one another without the mediation of other bits of matter are possible in a spatiomaterial world, because if space and matter are both substances, then not only can space and matter affect one another, but parts of space can affect one another. Though a bit of matter can affect only those parts of space with which it coincides (but not any distant parts of space), it is possible for a bit of matter to have effects on space itself that affect other parts of space and, thereby, the bits of matter that coincide with distant parts of space. However, if there were such effects (and, as we shall see, there are, though they are severely limited), the ontological causes of the principle of local action would impose the same constraint on them. One bit of matter cannot have effects on other bits of matter at a distance by way its effects on space without some change in space traveling across space as time passes from the location of the one bit of matter to the location of the other.

There is no reason to doubt that it is possible for parts of space to affect one another. Parts of space are particular substances, even though they all have necessary geometrical relations to one another. Each part of space, as a substance, endures through time, and spatiomaterialism leaves open the possibility that parts of space have properties that can change under certain circumstances (though that would be a temporally complex aspect of the essential nature of space, since there is no deeper ontological explanation of it). However, spatiomaterialism does imply that, if a property of one part of space can change a property of other parts of space, it can affect only neighboring parts of space, so that in order to affect parts of space at a distance, the effect would have to propagate across space as time passes. Such a further causal connection among the parts of space could mediate the effect of one bit of matter on bits of matter at a distance from it, but it would depend on some change traveling across space as time passes. And it would have to be at a finite velocity, for effects with an infinite velocity would be effects at a distance.

What is relevant here is the general principle that what happens to the bits of matter in one location cannot affect (either interact with or have an effect on) what happens to bits of matter located elsewhere without something traveling across the space separating them. What moves across space may be another bit of matter, or it may a change in space itself. But those are the only ways for one to change the other, because bits of matter have no connection with one another except for how they coincide with parts of space.

If a bit of matter were to get from one location to the other without moving across space in time, it would violate the principle of motion. And its velocity must be finite, or else the bit of matter would be flitting about.

If a modification in one location of space were to affect other locations in space immediately, it would mean that space is not made up of parts of space that endure through time as distinct substances. Though the geometrical relations among parts of space are aspects of their essential natures, they are distinct substances related geometrically, that is, by way of the parts of space between them, and any change in one part of space must first produce real changes to the parts in between before it can affect more distant parts of space. And it must propagate at a finite velocity, or it would not be propagating at all.

In either case, whether the action is mediated by a bit of matter or by space itself, something must move across space as time passes, or there can be no effect of one on the other.

The principle of local action (and effects) denies that there is any action (or effect) at a distance. Though action at a distance is ontologically impossible in a spatiomaterial world, it is conceivable, because if space were not a substance, but merely a kind of relation that holds among bits of matter (or an aspect of how they exist together as a world), the relations postulated might include bits of matter acting on one another at a distance. Such a spatial relationism would be a kind of materialism. But substantivalism about space makes action at a distance impossible, because bits of matter at a distance from one another are separated (and connected) by all the other spatial substances that exist between (and around) them. Space is the ontological cause that limits interaction to local actions.

Empirical science explains events and conditions by efficient causes, but if those causal connections have ontological explanations at all (and those connections are not merely assumed as part of the specific nature of matter or space), they must be mediated by the motion and interaction of bits of matter in space (or effects in space) as time passes, because nothing else is permitted by the necessary principles of local motion and local action. We shall see that spatiomaterialism can go quite a way in explaining efficient causes ontologically, but it may be possible to go even farther than what is sketched here.

Contingent laws about local regularities.Though certain kinds of events are ruled out as ontologically impossible by the necessary principles about local regularities, that leaves open many ways for bits of matter to behave. Indeed, it leaves open the possibility that no change actually takes place at all. But if bits of matter in space do change as time passes, they must change in determinate ways, and how they move and interact is what is described by the basic laws of physics. Since that is something that can be known only by observing what happens in nature, those regularities are not ontologically necessary. Assuming that they have ontological causes, they depend on the specific kind of matter and specific kind of space that constitute the actual world. Thus, although spatiomaterialism explains the basic nature of what exists, ontological philosophy needs to make additional assumptions about the specific essential natures of the matter and space it postulates in order to explain the truth of the basic laws of physics.

The properties mentioned in basic laws of physics are called “physical properties,” and as noted in Properties, ontological philosophy takes physical properties to characterize the extrinsic essential aspects of the nature of matter and space. (Intrinsic essential natures, by contrast, are what explain phenomenal properties.) And in the same way that physical properties (and spatial relations) are explained as aspects of the basic substances constituting the world, basic physical laws describing how they change can be explained as aspects of those substances as they endure through time.

If the matter postulated by an ontology were simply assumed to have whatever essential nature is required to make the basic laws of physics true, there would be no genuine ontological explanation of why the basic physical laws are true. That is what materialism does (hence, its other name, “physicalism”). Indeed, that is the only way that physical properties can be introduced by materialism, because when space is reduced to spatial relations among bits of matter (as materialism does, being implicitly committed to spatial relationism), matter is the only possible ontological cause of physical properties and regularities about how they change over time. But a spatiomaterialist ontology recognizes two basically different ontological causes, and so space can work together with matter to constitute properties, relations, and how they change over time. When it comes to explaining the truth of physics, therefore, what ontological philosophy is looking for is a description of a more specific essential nature of matter and space such that, when space contains all the bits of matter, objects have physical properties and spatial relations which change in the ways described by the basic laws of physics.

It may not be surprising that spatiomaterialism can explain the truth of the physics that prevailed at about the end of the 19th Century, because classical physics afforded an intuitive understanding of the laws of physics, as descriptions of how material substances move and interact in space as time passes and it assumed that space and time are absolute. What cast doubt on the possibility of a spatiomaterialist explanation were the revolutions that spawned contemporary physics. In particular, relativity theory seems to deny that space and time are absolute, as spatiomaterialism requires. Thus, instead of looking for a spatiomaterialist ontology that would make relativity theory (and the other laws of physics) true, contemporary physicists see the “holy grail of physics” as merely discovering a “Theory of Everything,” that is, a single law from which all the other laws can be derived.

At present, there are four basic laws of physics, each describing one of the four basic forces that are now thought to be at work in nature (electromagnetism, the strong force, the weak force, and gravitation), and the task that physics has set itself is to discover a single law that entails (together with suitable initial and boundary conditions) all four of those laws. (That seems possible in the case of the first three, because they can all be formulated as gauge field theories, but attempts to formulate Einstein’s general theory of relativity in a compatible way have been forced to assume that there are as many ten or eleven dimensions to space )

To take the goal to be the discover of a single, basic law is to assume that efficient-cause explanations are the most basic explanations that physics can give. And since ontology itself is not assumed to be explanatory, the only entities that contemporary physics takes to be real are those referred to by the basic law of physics, that is, scientific realism.

Ontological philosophy, on the other hand, assumes that ontology itself is explanatory. That is what led us to recognize that the world is constituted by space as well as matter. Thus, we now expect space and matter to work together is some way to explain the truth of the basic laws of physics and, thereby, the truth of its efficient-cause explanations. Indeed, one of the mortgages we took out in order to use spatiomaterialism as our ontological foundation in proving necessary truths was the promise to give such an explanation of Einstein’s two relativity theories. We promised to show that even though we must take space and time to be absolute, it is possible to describe more specific essential natures of matter and space that would entail the truth of the special and general theories of relativity. But in order to lay the foundation for such a theory, we must first describe more specific essential natures of matter and space that would entail the truth of the laws of classical physics.

The attempt to discover the specific essential natures of matter and space in the actual world is, however, a project resembling empirical science, for it would have to discover which essential nature(s) of matter and space afford the best ontological explanation of the truths of the basic laws of physics in a spatiomaterial world. That is a project of empirical ontology, but nothing so definitive is claimed for what is sketched here. All that is required here is proof that it is possible to give such an ontological explanation of the truth of physical laws, for that will show that spatiomaterialism is not falsified by what is found empirical in nature by physics and, thus, that ontology affords a new approach to philosophy. Thus, though this sketch of how more specific essential natures of matter and space explain their truth will show that a deeper explanation is possible, it may not be the best ontological explanation of physics. That job can be left to ontology as branch of empirical, natural science that is more basic than physics.

Once it is recognized that ontological-cause explanation are prior to efficient-cause explanations, finding the best ontological explanation will become the “holy grail” of the most basic branch of natural science. Unlikely as it may seem now, physicists will eventually welcome substantivalism about space, because it opens up the possibility of a deeper explanation of the world and what physicists really want is the deepest possible explanation that can be supported by the empirical method. As we shall see, for example, it solves the current puzzle about the relationship between gravitation and the other three basic forces of nature.

Contingent laws: Classical physics.We begin with the spatiomaterialist ontological explanation of the truth of the basic laws of classical physics, including Newton’s laws of motion and gravitation and Maxwell’s laws of electromagnetism. If they can be explained ontologically, we can be confident that the rest of classical physics can also be explained ontologically, for the basic physical laws are like the axioms of a formal system and the rest of physics are like theorems that follow from them. That is basically the strategy we used for mathematics, ontologically explaining the truth of the axioms of set theory from which the rest of mathematics follows.

Though classical physicists assumed that space is absolute, they did not try to give an ontological explanation of the truth of the basic physical laws based on space being a substance. They did not recognize the validity of ontological explanations, and so they did not think of space as a substance that works together with matter to make the regularities being described true. Indeed, the action at a distance implied by Newton’s law of gravitation must have made any such project seem hopeless. Instead, their aim was to formulate physical laws mathematically so that they could make quantitatively precise predictions of the measurements that would be made in experimental situations. That method turned out to be a powerful means of seeing into the nature of the world, most spectacularly by revealing the nature of micro-processes, though by leaving out the deeper ontological explanation, it also made the Einsteinian revolution inevitable, as we shall see.

The simplest way to describe the specific natures of matter and space that would explain the truth of classical physics is to start by cataloging all the different entities mentioned by the laws of physics and showing how the forms of matter required to account for them all would, by being contained by space and enduring through time, make the regularities described by the basic laws of classical physics true. That method will leave some aspects of those regularities built into the natures that the kinds of matter and space that are assumed to constitute a spatiomaterial world like ours. But enough of those regularities will be given a genuine explanation to show that an ontological explanation of classical physics is possible -- and to lay the foundation for explaining how the basic laws of contemporary physics could be true in a spatiomaterial world.

Forms of matter.Though we cannot assume anything about the nature of matter or space that contradicts spatiomaterialism, there are many different possible spatiomaterial worlds. It is mainly the more specific nature of matter that we will be concerned with in explaining the truth of classical physics, and in any given spatiomaterial world, bits of matter may come in various forms, each with different ways of moving, interacting and being related to bits of matter in other forms.

Indeed, we will have to assume that matter takes qualitatively different forms, because the basic laws of classical physics mention entities that are as different from one another as material objects and light. Every basic entity mentioned by physics as having a location in space and time must be explained as matter contained by space.

A promising way to inventory all the basic forms of matter required to explain the laws of classical physic ontologically is to take as our working hypothesis that what is conserved according to the principles of the conservation of mass and energy is the quantity of the matter contained by space. Conservation of mass and energy is one of the most basic principles of contemporary physics, and this ontological thesis is a plausible interpretation of it. Indeed, when the principle was first recognized by physics, it was heralded as empirical confirmation of the traditional materialist view that physical processes are made up of substances that endure through time. Let us, therefore, take it as our working hypothesis.

The principle of the conservation of mass and energy holds that in any closed or isolated region of space, there is a certain quantity of mass and energy that never changes, regardless what happens there. That quantity could be the total quantity of matter, for that hypothesis would explain two aspects of the principle.

First, since matter is a substance, it neither comes into existence nor goes out of existence as time passes, and thus, it is conserved. Hence, the quantity of mass and energy could be the quantity of matter.

Second, the principles of local motion and local action explain why the quantity of matter does not change under the conditions described by the principle of conservation of mass and energy. If the only way that bits of matter can change location is by motion, they cannot change their location from inside the closed or isolated region to outside, or vice versa, unless they cross the boundary, and that is excluded. Nor can bits of matter outside the closed region affect what happens to the bits of matter inside, since that would involve action at a distance, contrary to the principle of local action (unless something moved across the boundary between inside and outside to mediate the force, which is excluded).

Let us set aside the peculiar effects that bits of matter may have on one another that are mediated by space itself, since they are not relevant to classical physics. As we shall see, there are always such effects crossing the boundaries, but they do not violate this conservation principle, because, as it turns out, they carry neither energy nor mass.

Thus, it is plausible that the quantity to which classical physics is referring in the principle of the conservation of mass and energy is the total quantity of matter in closed or isolated regions of space.

There is, however, one aspect of contemporary physics that is relevant at this point in our argument. Though mass and energy were thought to be conserved separately in classical physics, Einstein discovered, as a consequence of his special theory of relativity, the famous equation connecting them (E=mc2). That is further evidence that mass and energy are just different forms of the same basic material substance, because if they were different forms of matter, we would expect them to be commensurable.

Indeed, the suggestion that they are basically the same stuff has turned out to be true, for there are actual physical processes in which they are converted into one another, most spectacularly in the nuclear reactions used in nuclear weapons (fission and fusion).

The conservation of mass and energy is now seen as a consequence (or presupposition) of the basic laws of contemporary physics. It is a way of formulating what is called a “symmetry” about those laws, that is, something that is invariant as other things change. But that it to treat it formally, as a basic symmetry principle of contemporary physics, and here, it will be interpreted ontologically, as describing an aspect of the world that is caused by the permanence of the matter that coincides with space.

Furthermore, the conversion between mass and energy will be assumed here in order to explain the various forms of matter ontologically, quite apart from explaining any of the phenomena covered by Einstein’s special theory of relativity.

The assumption that all the forms of mass and energy described by physics are various forms of matter that coincide with space is just a working hypothesis. It will serve my purposes, because it is a simple and plausible way of laying out an ontological explanation of the laws of physics (classical and contemporary) and, as we shall see, it does show that there is at least one way that spatiomaterialism can explain them all ontologically. Though it may not be the best spatiomaterialist explanation of them, it will suffice to provide an ontological foundation for explaining the global regularities, because it will show that, for all that physics knows empirically, spatiomaterialism could be true.

This ontological explanation of the truth of the principle of conservation of mass and energy implies that there are as many different forms of matter as there are kinds of mass and energy recognized by physics in confirming this principle empirically. And in order to explain the truth of the laws of classical physics, we must recognize four (or, perhaps, six) qualitatively different forms of matter (with varieties of each). They are (1) material objects with rest mass, (2) the kinetic energy involved in the motion of rest masses, (3) the energy due to gravitation, and (4) the energy due to electromagnetism. (Since the latter two each involve two basically different forms of energy, as potential energy and as actual waves, they might better be counted as two forms of matter each, yielding a total of six.) Let us consider briefly how each kind of energy can be explained as a form of matter and then we will see how these forms of matter would explain ontologically the truth of the laws of classical physics.

Matter as material objects with (rest) mass. Material objects with rest mass are the form of matter that is usually intended when people think of matter. Ordinary material objects have definite locations in space and can be at rest. The quantity of rest mass in any such object (at rest) would be the quantity of matter constituting its existence. The endurance of matter through time would then explain the principle of the conservation of mass in classical physics.

Even at the altitude of classical physics, however, material objects have further properties. Since different material objects cannot occupy the same places at the same times, some sort of interaction keeps them from doing so, when their motion would otherwise bring them to the same location. Such interactions are explained in physics by forces that the objects exert one another.

Thus, we will assume that some material objects have electric charges by which they can interact with other charged objects. And we will assume that every material object exerts a gravitational force by which it attracts every other material object. Such forces are, as we shall see, aspects of the matter that exists in the form of rest mass, and since these aspects involve regularities about change, they are dispositional properties.

However, since the forces are spread out in the space surrounding where the material object with rest mass is located, we must assume that some of the matter constituting its existence is somehow spread out in space, for otherwise the matter would not be able to explain the forces that the material objects exert. But as we shall see, all the matter constituting the material object is counted in its rest mass, and the object interacts as if all its (rest) mass were concentrated at its center, where the material object itself is said to be located.

We will also assume, as classical physics did, that ordinary material objects, such a billiard balls and cream puffs, are composed of simpler material objects, such as “atoms,” the parts of atoms (protons, neutrons and electrons), and the parts of parts of atoms (such as quarks), though we will also leave the natures of these particles and the forces binding them together unexplained until we take up contemporary physics.

The simplest parts of material objects are now known to be particles that are quite unlike material objects in various ways, but I will just assume that they can also be explained ontologically by spatiomaterialism until I show that the truth of quantum mechanics can be explained ontologically by spatiomaterialism. (The nature of the basic particles of physics is explained ontologically in Change: Cosmology: Basic objects.)

Kinetic matter. All the other forms of matter recognized by classical physics are classified as energy by physics, and the most surprising implication of this ontological explanation of classical physics is probably that kinetic energy is a form of matter, for it means that the motion of objects with rest mass is itself a form of matter. There is no way to avoid this implication, given our working hypothesis, because even in classical physics, kinetic energy can be converted into other forms of energy (such a light and potential energy), and other forms of energy can be converted into kinetic energy.

To hold that kinetic energy is a form of matter is to hold that the motion of a material object is constituted by a bit of matter that exists in addition to the matter counted in the (rest) mass of the material object. This bit of matter must somehow be attached to (and, therefore, located with) the matter that makes up the rest mass of the material object, and as a result, both must coincide with space in a way that carries it and the material object across space as time passes. Let us call it “kinetic matter.” More will be said about the essential nature of matter in this form when we take up quantum mechanics, but for now we need only recognize that quantitatively different varieties of kinetic matter would propel objects at different speeds or in different directions. Kinetic matter would be like a motor, except that instead of consuming energy, it is just a bit of matter that endures through time as a substance, and thus, as long as it continues to exist in that form, the material object continues to move. There are, however, interactions by which kinetic matter can be transferred to other material objects, supplemented with kinetic matter transferred from other material objects to join it, and converted into other forms of matter.

To treat kinetic energy as a form of matter is to depart from the received understanding of physics. Kinetic energy is usually treated abstractly as just another quantity that is mentioned in the laws of physics and must be taken into account in order to predict or control what happens in particular situations. When we think of kinetic energy as a form of matter, however, we expect to find other properties that it must have, and that is what leads to a deeper ontological explanation. Kinetic matter must be located, as we have assumed, with the rest mass that it is moving, and as we shall see in explaining quantum mechanics ontologically, kinetic matter has other properties that explain the quantitative relationship between kinetic energy and momentum.

The other forms of matter into which kinetic matter can be converted are those postulated in order to explain gravitation and electromagnetism. Gravitation and electromagnetism are forces that material objects exert on one another, and in order to explain the distinctive kind of energy involved in each, we will assume that the forces themselves are a form of matter. That is, the energy (or matter) associated with these forces can exist in two different forms, potential or actual (that is, as forces being exerted by material objects or as waves of forces that exist independently of material objects).

Potential energy. Potential energy is the energy that material objects have when they exert forces on one another. Such forces must be a form of energy, because they can change how the objects involved are moving.

The amount of potential energy that exists in any situation depends on the distance across which the forces can continue to accelerate the objects involved. When the distance is maximum, the potential energy is maximum. But physics sets the maximum quantity at zero. Thus, any subsequent state in which some potential energy has been converted into kinetic energy (or into some other form of energy) is counted as negative potential energy. This is sometimes said to be just a mathematical convention, but according to this ontological explanation of potential energy, it represents the fact that the kinetic energy acquired by objects being accelerated is another form of the same matter that previously existed in the form of potential energy, that is, as forces being exerted by the material objects.

As suggested above, some of the matter making up a material object that exerts a force must be conceived as being spread out in the space around it as a force field, and that matter is counted as part of its rest mass. When potential energy is consumed, objects accelerate, changing the positions of the objects that were exerting the forces. That alters the force field they jointly impose on space, and the result is a reduction in the quantity of matter constituting those forces and, thus, the material objects themselves. That is, the material objects lose rest mass as their potential energy is consumed as kinetic energy, because some of the matter counted in the rest mass is converted from constituting a force field to constituting the motion of objects with rest mass.

On this ontological theory, therefore, the reason that the potential energy that is consumed as kinetic energy is negative (rather than just a smaller positive quantity) is that the kinetic energy must be subtracted from the rest masses of the material objects that were exerting the forces in order to balance the account. The kinetic energy is a different form of the same bits of matter that previously existed as forces being exerted by the objects. Thus, at the end of such a process, when as much kinetic (or other) energy has been actualized as possible in the situation, the material objects are in a position where their forces cannot accelerate one another and more, and the potential energy is some negative quantity. And since the total quantity of energy (or matter) involved in the process does not change as time passes, the principle of the conservation of mass and energy is true.

Though the equivalence of mass and energy is entailed by Einstein’s special theory of relativity, it is assumed here, as I warned earlier, in order to explain ontologically the conversion of energy between kinetic and potential forms.

The matter that explains potential energy is, therefore, included as part of the matter that explains the (rest) masses of material objects, and as we shall assume, it is the matter that constitutes the forces exerted by the object. Since those forces are spread out in space like a field, this is to take the force field to be a form of matter that coincides with all those parts of space. Likewise, the strength of the force at any point in space will be taken as a measure of the “thickness” of the matter coinciding with space at that point. And the total potential energy that can be converted to kinetic energy (or other forms of energy) depends on the total amount of matter in this form that exists along the pathway of the object being accelerated (which depends on the length of the path and the “thickness” of the matter at each point along the path)

To be sure, this ontological assumption will seem empirically unwarranted from the point of view of inferring to the best efficient-cause explanation. What happens in the relevant situations can be predicted with laws describing the forces and descriptions of the locations of the kinds of objects involved, without any need to refer to matter making up the forces involved. In the received formulations of physics, force fields are usually explained as spatially variable dispositions, that is, in terms of regularities about how material objects of certain kinds would be accelerated, if they were located there. But ontologically speaking, there must be a substance located there to accelerate the body, and though this description of matter in the form of potential energy does not tell us much more about it than is described by the relevant laws of physics, it does make us look for further properties of such force-field matter. Such properties will be described in the ontological explanations of Einstein's general theory of relativity and quantum mechanics.

More generally, furthermore, remember that we already have empirical reasons for believing that space and matter are substances, and what is at issue is whether the laws of physics can be descriptions of regular changes in the aspects the basic substances we have postulated. This is not an attempt to show that physics must recognize matter in these forms in order to predict what will happen, but only that it can and, thus, that physics provides no reason do doubt that spatiomaterialism is true.

Energy as waves of forces. If forces are a part of the matter constituting the rest mass of a material object that is spread out in space around it, then references to that matter by way of rest masses and as negative energy are indirect, and they obscure its real nature. Moreover, there is other evidence that forces are a form of matter, for such forces can also exist independently of material objects (that is, when they are not counted as part of their rest masses). They exist as light waves, in the case of electromagnetism, and as gravitational waves, though the latter were not recognized until Einstein’s discovery of the general theory of relativity. In both cases, the waves propagate across space on their own, and since they act on objects that they encounter in their paths like forces of the appropriate kind, those waves are best explained as matter existing in much same form that helps constitute the rest masses of material objects, except that it now exist independently of material objects. But given the difference between its form as part of the rest mass of material object and its form as an independently existing wave, we should probably postulate two different forms of matter for each kind of energy, gravitational and electromagnetic (yielding six forms of matter in all).

Gravitational matter. The nature of the force of gravity was problematic in classical physics, because it was supposed to enable material objects to act on one another at a distance, and an adequate ontological explanation of it cannot be given here until we take up the spatiomaterialist interpretation of Einstein’s general theory of relativity. According to Newton, gravity is a universal force of attraction among material objects whose strength is in proportion to the products of their masses and inversely proportional the square of the distance separating them. When material objects (and energy) have accumulated at a certain location in space, as in planets and stars, the gravitational force is strong enough to make an enormous difference in what happens in the surrounding space.

According to contemporary physics, the mass that is responsible for gravitation is not just the rest masses of the material objects, but also includes the mass equivalent of their kinetic energy and electromagnetic energy. That is readily explained by this ontological theory, if matter in all forms exerts gravitational forces, and it will be assumed here.

Without giving a deeper explanation of its nature, we can think of the gravitational force field as a form of matter that is spread out in the space around the center of gravity and has the power where it is located to accelerate towards itself other material objects that coincide with the same part of space. The strength of the force at any location as described by Newton’s law can be thought of as varying with the amount (or “thickness”) of matter in this form spread out in that part of space. But since the quantity of gravitational matter is already counted in the rest mass of the matter accumulated at that location, the force field is just an aspect of the accumulated matter (or an extrinsic property of the matter located there).

Though we are assuming that the gravitational force field is a form of matter in order to explain how classical physics is true, I promise to give a deeper ontological explanation of gravitational matter and how it is related to other forms of matter in making up the rest mass of a material object when we take up contemporary physics. But for now, spatiomaterialism leaves us no option but to recognize the gravitational force itself as a form of matter in some sense, for otherwise there would be nothing to exert the forces involved. Space by itself cannot exert gravitational forces, because they vary with location, whereas space is uniform throughout. But as we shall see, gravitational matter can be a condition of space that is imposed on it by the accumulation of matter at a nearby location.

Gravitational potential energy is the matter that can be extracted from material objects because they are so located relative to one another in space that the gravitational forces that they exert on one another can accelerate them toward one another. When gravitation accelerates material objects to the some location, they acquire kinetic energy, and when they collide, some of it may be turned into other forms of energy. Though that means, on this ontological explanation, that the material objects involved have less rest mass than they did when they were still attracting one another across the distance separating them, there is no violation of the principle of the conservation of mass and energy, because the missing rest mass is now counted as the kinetic (and other forms) of energy of the objects at the center. The reason that classical physics does not recognize that the rest masses of the material objects at the center of gravitation have become less than they were before they accumulated there is that it assumes that any potential energy that is less than the maximum possible is a negative quantity.

In particular, it is possible to hold that the kinetic (and other forms of) energy that material objects acquire as they accelerate toward one another comes from the gravitational matter that was spread out in the space between them, because the motions of the objects so alters the force field between them that less gravitational matter is required for them to exert a gravitational force on one another.

The total matter, both rest mass and forms of energy, accumulated at the center of gravitation determines the strength of the gravitational field around that center, and the field is stronger than it was when the material objects were still separated, even though some gravitational matter has been converted to kinetic (and other forms of) energy, because the accumulation of bits of matter at the same location makes their gravitational fields coincide more completely with the same parts of space, so that the gravitational matter at any location in the field they jointly impose on space is spread more thickly.

Though gravitational matter is just part of matter counted in the rest mass of a material object, gravitational matter can also exist independently, as gravitational waves. But we can leave that until we take up the ontological explanation of Einstein’s general theory of relativity.

Electromagnetic matter. The electric force is another kind of force that we will assume that material objects can exert. It has a more complicated structure than gravity, because material objects can exert two opposite electric forces, positive and negative, and in either case, the electric force interacts with another force, the magnetic force. How material objects interact by these forces is what is described by Maxwell’s laws, and they will be explained in more detail later. For now, let me merely suggest how electric forces can be explained as a form of matter, by analogy with gravitational matter.

Material objects that exert an electric force are said to have an electric charge, either positive or negative. In order to explain ontologically how Maxwell’s laws are true, we will assume that the matter making up such a material object coincides with space in a way that makes its total rest mass seem to have a determinate location at the center even though some of its constituent matter is spread out around it like a force field. Since the strength of the forces in this field fall off in proportion to the square of the distance from the center, their strength at any point can also be explained as the “thickness” of the electromagnetic matter spread out in that part of space, though it must have a more complex structure to explain the direction of the force, because it depends on the sign of the charge and its motion.

The electromagnetic matter making up the electric field is already counted as part of the rest mass of the material object in balancing the mass and energy books. Thus, the electric field is actually an aspect of the material object, that is, an extrinsic property of the material substance that has the electric charge.

Electromagnetic matter in this form is electrical potential energy, because the force field can accelerate material objects affected by it, namely, other material objects with electric charges. Like gravitational potential energy, electromagnetic matter is converted to kinetic (or other forms of) energy, and such conversions change the rest masses of the objects exerting the electric forces appropriately, because material objects are actually either acquiring or losing matter. But once again, the changes in rest mass may not be recognized as such, because any amount of potential energy less than the maximum possible is counted as a negative quantity.

In the case of electromagnetism, the interaction of electric forces with magnetic forces makes it necessary to recognize that matter of basically the same kind can also exist independently of material objects as waves, such as ordinary light.

When these two forces are coupled, as described below, they propagate across space as a wave of electric and magnetic forces. Since those forces interact with charged objects in much the same way as the electric (or magnetic) forces exerted by material objects directly, electromagnetic waves are basically another form of electromagnetic matter. But since the electric (and magnetic) forces exerted by charged material objects directly are so different from electromagnetic waves, it is probably best to think of electromagnetic matter as existing in two different forms. In one form, its quantity is included in the rest masses of the objects (and the negative potential energy of the situation), and in the other form it is added to the rest of the mass and energy in calculating the total quantity that does not change over time in a closed or isolated system.

Electromagnetic energy is not portrayed as mere waves in contemporary physics. There are two reasons, one that we will accept in the end and one that we won’t.

The first reason is that electromagnetic waves are now known to have a particle-like nature, which has given them the name “photons.” The discovery of their particle-like nature is at the very foundation of quantum mechanics, and it will not be disputed here. We shall see how spatiomaterialism can explain their particle-like when we take up the ontological explanation of quantum mechanics.

The second reason for avoiding the notion of electromagnetic waves is that the notion of waves requires a substratum or medium in which the waves occur, such as the water in which ocean waves occur and the air in which sound waves occur. In classical physics, electromagnetic waves were thought to occur in the “luminiferous ether,” which was assumed to be at rest in absolute space. But when absolute space was rejected with the rise of relativity theory, the notion that light propagates in such a medium was rejected with it. Spatiomaterialism entails, however, that space and time are absolute, and so we do not have that reason for denying the reality of the ether. And since our reason for accepting absolute space and time is that space is a substance (not merely a way of thinking about references to locations and times in the equations of physics, as classical physics did), we have the option of explaining the ether ontologically, that is, as an aspect of space itself.

In other words, we will take the motion of electromagnetic waves to exhibit an aspect of the nature of space. Much the same is true of any form of matter, because the properties of any bit of matter are an aspect of something constituted jointly by the bit of matter and the part of space with which it coincides. But in the case of electromagnetic waves, we will hold that their velocity, that is, the velocity of light, manifests a basic aspect of the nature of space (what will be called the “inherent motion” of space or the “ether”).

It may seem that there are other kinds of energy, besides kinetic energy and the energy that is due to electromagnetism and gravitation, recognized in classical physics, but they all turn out in the end to be reducible to these basic forms.

Chemical energy, for example, is a form of potential electromagnetic energy that depends on how charged particles are configured in atoms and molecules. Heat turns out to be the kinetic energy in the random motion of the smallest material objects. Kinetic energy can also be stored internally in molecules as vibrations of parts of atoms.

There are, of course, other forms of energy associated with the short range forces that are involved in the constitution of more basic material objects, such as the strong forces exerted by protons and neutrons (or the color forces exerted by quarks) and the weak forces that are apparently involved in the constitution of quarks and electrons (and show up observationally in radioactive decay). But we are leaving them aside until we take up contemporary physics, taking the internal structure of material objects with rest mass for granted.

The reason we are taking all these kinds of mass and energy to be forms of matter is that they can be converted into one another without changing the total mass and energy in the region, that is, because the total mass and energy is conserved. Electromagnetic waves interacting with charged particles can convert them into kinetic energy. But this ontological explanation of classical physics takes the conversion between potential and kinetic energy to be an instance of the convertibility of mass and energy into one another. How these forms of mass and energy are converted into one another is described by the basic laws of physics.

To hold that these kinds of mass and energy are basically different forms of matter which move and interact in the ways described by the laws of physics is to hold that matter has a temporally complex nature. What is assumed about the essential nature of matter must include how each kind moves and interacts, including how they change from one form of matter to another.

However, spatiomaterialism opens up the possibility of a deeper ontological explanation of how these forms of matter are related to one another, which might explain how they can be converted into one another. Since ontological philosophy takes space to be a substance, it may be possible to describe the essential nature of matter in a way that makes it possible to explain ontologically why it takes these different forms by how generic matter coincides with space and other bits of matter. That is to suppose that the same material substance could have the properties defining any special form depending on its current relationship to space (and, perhaps, other bits of matter at its location).

For example, if there were a geometrical aspect to generic matter, differences in the forms mentioned above (or some of them) might have an intelligible ontological explanation as different ways in which generic matter engages with the geometrical structure of space. An explanation of the nature of some forms of matter along these lines will be suggested by a theory about the nature of matter that will be offered as an ontological explanation of the truth of quantum mechanics, and it will explain the simplest particles recognized by physics (in Basic Objects under Cosmology under Change.) It illustrates a research project that would be promising, if ontological philosophy is on the right track.

To explain the truth of the laws of physics by postulating a kind of material substance that can change from one form to another with different essential properties is to make the forms of matter similar to Aristotle’s basic substances. Aristotle believed that the simplest kinds of substances (earth, air, fire and water) could be converted into one another, for example, as fire gives its form to other substances, such as wood, changing its essential form to fire. As the essential properties (or essential form) of the substances change, the substratum (or material cause) was supposed to endure unchanged. There is, however, a difference. Spatiomaterialism does not assume, as Aristotle did, that (essential) forms of matter and their substratum are basic principles. Spatiomaterialism is a variety of materialism, in Aristotle’s sense, because it denies that individual substances necessarily involve his two principles (or ontological causes), substratum (material cause) and essential form. Bits of matter are independent substances, and their capacity to change from one form of matter to another is just part of the essential nature of material substance. However, since spatiomaterialism does recognize another basic kind of substance, besides matter, with which it coincides, it is possible that those regularities have a deeper ontological explanation.

Leaving aside for now deeper ontological explanations of these forms of matter, our project here is to show that classical physics can be explained ontologically by spatiomaterialism. That is to explain the truth of the laws of classical physics by their correspondence to aspects of a spatiomaterialism world, and it will be accomplished here by assuming that the bits of matter that coincide with space have these basic forms: material objects with rest mass, kinetic matter, gravitational matter (as part of the matter making up objects with rest mass) and electromagnetic matter (both as part of the matter making up material objects with electric charges and as electromagnetic waves).

The laws to be explained are Newton’s laws of motion and gravitation as well as Maxwell’s laws of electromagnetism. That will suffice to show how the physical properties mentioned by the basic laws of classical physics can be aspects of these forms of matter, and it will explain the regularities among them as temporal aspects of a world constituted by such substances enduring through time.

Since what is at issue is the correspondence between these laws and aspects of substances, what is crucial is not the quantitative aspects of those laws, which are generally the focus of attention in physics, but how those quantities can be explained ontologically by substances of the kind postulated by spatiomaterialism. I will describe how aspects of these forms of matter would explain the properties mentioned by the laws of physics, and I will show that they can explain the quantitative relationships among them and how they change over time. But I will merely show that the quantities can all have the right signs, change in the right directions and have the right orders of magnitude. It is not a matter of making any new, quantitatively precise predictions of what will happen, because any more precise quantitative correspondence can be made to come out right simply by making the right assumption about the essential nature of matter. It is enough to explain them ontologically.

Not every aspect of those physical laws will be given a genuine ontological explanation. But enough will be explained to show that it is possible for spatiomaterialism to explain the truth of classical physics. That will put us in a position to show how spatiomaterialism can also explain the truth of contemporary physics, both relativity theory and quantum mechanics. We begin by sketching an ontological explanation of Newton’s laws of motion and gravitation and then take up Maxwell’s laws of electromagnetism.

Newton’s laws of motion.Newton’s laws of motion are remarkably simple.

First law of motion: “Every body continues in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed on it.”

Second law of motion: “The change of motion is proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed.”

Third law of motion: “To every action there is always opposed an equal reaction; or, the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.”

Law of gravitation: material objects always attract one another in proportion to the product of their masses and inversely as the square of the distance separating them.

Newton’s laws describe how material objects move and interact, and since we postulate matter in the form of material objects with rest mass, we need only see how the regularities described by Newton’s laws of motion would be explained on the assumption that kinetic energy and potential energy are forms of matter as well. That requires making further assumptions about the specific essential natures of these forms of matter and about space, but as we shall see, it affords genuine, even illuminating, ontological explanations of some aspects of classical physics.

According to our working hypothesis, the motion of a material object with rest mass is due to the kinetic matter attached to it. The kinetic matter must coincide with the same part of space as the material object itself, but in a way that that moves the material object across space as time passes. Each speed and direction of motion for any given material objects would involve a (quantitatively) different variety of kinetic matter (which could be explained ontologically by aspects of how kinetic matter coincides with space, such as its direction and quantity).

Newton’s first law of motion.Newton’s first law is an immediate consequence of this ontological assumption about kinetic matter. Since the kinetic matter that makes the material object move is itself a substance that endures through time with the same essential nature, the object in motion will continue moving at the same speed and in the same direction (unless it interacts with another bit of matter).

What does not change according to the first law of motion is called “velocity,” because it includes two aspects of the object’s motion, its speed and its direction. That is why we assume that, for any given material object, each different speed and each different direction requires a different variety of kinetic matter. The velocity is not the kinetic matter, but just a property of the material object with the kinetic matter, that is, an aspect of the substances constituting the object with rest mass together with its kinetic matter and how both are contained by space. (The three dimensional structure of space makes it possible to represent any velocity mathematically as a certain speed in each of any three mutually perpendicular directions. Quantities that depend on direction in this way are called “vectors.”)

Newton’s first law must be true, if the motion of objects is due to kinetic matter, because all the ways that an object might be thought to change its speed or direction on its own are ontologically impossible. A change in its motion would require kinetic matter of one variety to come into existence and another variety would have to go out of existence as time passes, which substances cannot do. Or it would require the variety of kinetic matter to change its essential nature, which no form of matter can do on its own. Or it would require space to contain kinetic matter in a different way at different locations, which is not compatible with the uniformity of space.

To be sure, in order to explain motion as a form of matter that connects material objects to space in a certain way, the objects must have an absolute velocity, that is, a certain velocity in absolute space. That may seem doubtful in contemporary physics, but it is just what spatiomaterialism entails about the nature of space and that is what is at issue in this ontological explanation of physics.

Notice that the assumption that an object’s velocity is due to its kinetic matter solves a problem that motion otherwise poses for any ontology that that postulates only substances enduring through time. The problem was first posed by Zeno as a paradox about motion. He pointed out that, at each moment, an object must be at rest (as we assume by holding that nothing exists but the present), and he asked, How is motion even possible in that case? If motion is simply how location changes as time passes, motion does not really exist, because the object always has only one location at each moment as it is present. This is not just a puzzle about the continuousness of time and space, because holding that to move is just to have a location that varies continuously with time leaves a problem about why the moving object has a different location the next moment, whereas the object at rest does not. What makes the object in motion different from the object at rest at each moment? To be sure, it is possible to simply assume that the essential nature of all material objects includes the temporally complex property of changing locations again, if it did so the last moment. That is what materialism does in this case (as in the case of every other basic law of physics), and it is not very satisfying, because there is nothing to distinguish the moving object from the one at rest at any moment except where each was the previous moment (which is not something that exists at that moment). If, however, motion is constituted by a bit of kinetic matter that exists in addition to the object with rest mass, then motion is actually a substance that endures through time, and thus, what makes the moving object at any moment different from an object at rest is something that exists at that moment (not just the fact that it has a different position the previous moment).

The first law of motion allows for velocity to change when the material object interacts with another object, and given the forms of matter we are postulating, the only way that a material object can change velocity is for kinetic matter to be transferred to it or from it or both. Somehow the object must come to have a different variety of kinetic matter attached to it. That is basically what interactions do to objects with rest mass. In such an interaction, Newton’s laws say that the object is subject to a force, and our working hypothesis implies that the exertion of a force on the object somehow transfers kinetic matter to and/or from it.

Interactions are something that we expect, given our assumption that material objects are a form of matter that cannot occupy the same place at the same time, because if they can move, they can move to the same location at the same time and something must keep them from being contained by the same part of space. The simplest kind of interaction is a collision of material objects that is elastic, that is, in which nothing changes but the velocities of the material objects that collide. Though collisions of ordinary material objects are mediated by electromagnetic interactions, we can, for present purposes, abstract from the nature of the forces and consider only what happens when material objects collide. We know that they exchange kinetic matter. But we do not know how much is transferred or what effect it has on their velocities. The regularities about such transfers of kinetic matter are what is described by Newton’s second and third laws of motion.

Newton’s second law of motion. Newton’s second law holds that the exertion of a force is what changes the velocity of a material object. Since forces are exerted by other objects, the force on any object has some direction or other, which determines in some way the direction in which the object’s speed changes. It also has a determinate strength and its action on the object has a certain quantity. But how much an object’s speed changes in the direction of any given force depends on another factor, its rest mass, or the quantity of matter embodied in it. That is, what changes when a material object is subject to a force is its momentum, or the product of its velocity and its rest mass.

In the case of material objects composed of many parts with the same rest mass, our working ontological hypothesis offers an explanation of the relevance of rest mass in determining the change of velocity. In order for the composite object to move in a certain way, each of objects of which it is composed (each “atom,” if you will) must move in the same way (assuming that the parts have unchanging spatial relations to one another). Since each part must be moved across space by its own bit of kinetic matter, a force can change the velocity of the whole only by changing the velocity of each part in the same way. Thus, the change in velocity caused by a force varies inversely with the total rest mass of the material object. It must be spread out among all the parts, so to speak. For example, an object with twice as much rest mass has half as much change in velocity, if subjected to the same force. In other words, what changes is not merely its velocity, but its momentum, the product of its velocity and its rest mass.

The second law of motion also holds in the case of elementary material objects with different rest masses. But without a deeper ontological explanation of the nature of kinetic matter and material objects with rest mass, that regularity can only be assumed as part of the essential natures of those forms of matter.

Velocity is not a measure of the amount of kinetic matter, because the change caused by the transfer of kinetic matter to or from an object depends on its rest mass. But it might seem that momentum is the measure of kinetic matter, since it is what changes when kinetic matter is transferred. However, momentum, like velocity, is just a property of the material object with kinetic matter, and we can begin to see why by considering the third law of motion.

Newton’s third law of motion.Newton’s third law describes a more inclusive regularity than the second, for it includes the object that is the source of the force, describing how it is affected as well. This law holds that the action of one object on another is opposed by an equal and opposite action of the other object back on the first. That is, every action of one object on another is actually a symmetrical interaction of the two objects involved. And since what the action changes is momentum, this law says that the change in the momentum of one object is equal and opposite to the change in momentum of the other object. Thus, Newton’s third law of motion entails the conservation of momentum. That is, in any interaction, the sum of the products of the velocity and mass of all the objects involved in the interaction does not change in any direction regardless how the objects may interact.

The conservation of momentum may make it seem that momentum must be the measure of the total quantity of kinetic matter involved. Suppose, for example, that two equally massive objects moving toward one another at the same speed were to collide. Given our working ontological hypothesis, we might try to understand why the two objects rebound from one another by thinking of the interaction as each object transferring its kinetic matter to the other, for that would also explain why both objects come out with velocities in the opposite direction. Each acquires the other object’s kinetic matter. And if the objects had different rest masses and different velocities, this would even explain how much the velocity of each changes.

Momentum cannot, however, be the measure of the amount of kinetic matter, because it is a quantity that depends on the direction of the motion, whereas the quantity of kinetic matter does not. (In other words, momentum is a “vector quantity,” whereas kinetic energy, as a substance, must be a “scalar quantity,” which does not depend on the direction of motion.) To illustrate the problem, suppose that two objects colliding with equal and opposite momentums do not rebound from one another, but simply come to a stop. The latter is compatible with Newton’s third law of motion, because the change in the momentum of one is still equal and opposite to the change in momentum of the other. Each loses an equal and opposite momentum. Action and reaction are symmetrical. But if momentum were the measure of kinetic matter, it would mean that their kinetic matter simply goes out of existence, for their momentums cancel out. And since that is impossible for a substance, momentum cannot be the measure of kinetic matter.

It is no great surprise, of course, that momentum is not the measure of the quantity of kinetic matter on this ontological explanation, for we postulated the existence of kinetic matter in the first place in order to account for kinetic energy. But the foregoing example does bring out the difference between momentum and kinetic energy. It is currently explained only mathematically: in Newtonian physics, momentum is the product of an object’s rest mass and its velocity (mv), whereas its kinetic energy is one-half the product of its rest mass and the square of its velocity (1/2 mv2).

It is a subtle difference, which was not obvious even to classical physicists at first. The difference was not recognized by Cartesians, and Leibniz was so struck by kinetic energy being different from momentum, or mere motion, that he took the existence kinetic energy as evidence of a vis viva, a “force of life” in the object, which helped inspire his belief that atoms are really “monads,” or minds.

The ontological difference between kinetic energy and momentum is that the former is the quantity of a form of matter that can be attached to objects with rest mass and the latter is a quantitative property that material objects have when kinetic matter is attached. Momentum is just an aspect of those two kinds of material substances as they are contained by space, an aspect that depends on the direction of the motion in space. Newton’s second and third laws of motion describe the regularity about how that property changes when material objects interact, including the conservation of momentum. The kinetic energy is, however, part of the substance constituting the object in motion, and so it is conserved because it is a substance.

This is just the beginning of an ontological explanation of the difference between kinetic energy and momentum. Though we can see that they are different, it does not explain the quantitative relationship between them, that is, why kinetic energy varies with the square of velocity, while momentum varies with velocity. That can be explained only later, when we take up a deeper ontological explanation, the quantum theory of matter. There is a more specific nature of kinetic matter that entails momentum being related to kinetic energy as the velocity to the square of velocity.

In the foregoing case, where colliding objects with equal and opposite momentums simply stop, the collision is not elastic, that is, something changes besides the motion of those objects. Instead of dropping out of existence, the kinetic energy is converted into another form of matter (such as potential energy in new forces being exerted among its parts) or transferred to other objects (such as the kinetic energy of the parts of the objects, that is, becoming heat).

Newton’s law of gravitation.Newton’s law of gravitation holds that material objects exert an attractive force on one another that is proportional to the product of their (rest) masses and inversely proportional to the distance between them. But since each object exerts such a force on the other, an object must have a gravitational field around it even when there are no other objects in its neighborhood. There is, in other words, a gravitational force at every location in the space around the material object. Those forces are radially symmetric around the object itself, and their strength declines with the square of the distance from the object.

The gravitational field is explained ontologically by postulating matter in the form of gravitational matter, which is spread out in space around the material object exerting the gravitational force, though its quantity is included, along with matter is some other (yet to be described) forms, as the rest mass of the material object. This affords an obvious ontological explanation of many of the aspects described by Newton’s law of gravitation. Gravitational forces are directed toward the object, since that is the center of the rest mass of the material object that spreads gravitational matter out in space. The forces are radically symmetric, because the object is located in three dimensional space. And the strength to the force falls off with the square of the distance, because that is how fast space spreads out sideways as you move away from the source of the force.

The force of gravity is not given an ontological explanation in classical physics. Instead, it is usually described as just a disposition at each point in space to exert a precise, mathematically described force on any material object (with a certain mass), if it were located at that point. Talk of “dispositions” is a way of predicating regularities of objects as if regularities were just properties of the objects. But that is to leave those regularities unexplained. There is no alternative in classical physics, because it assumed that gravity involves action at a distance (which is implicitly to deny the reality of the space across which it is supposed to act). Talk of gravitation as a disposition is a way of being skeptical about the reality of such forces as anything beyond their effects. This ontological problem was eliminated by Einstein’s general theory of relativity, and that discovery is what we are anticipating by including gravitational energy as a form of matter in this explanation of the truth of classical physics.

Gravitational matter helps explain the truth of the principle of the conservation of mass and energy, however, only by being counted as a negative quantity, that is, as potential energy. The maximum quantity of potential energy is zero, because according to our our ontological explanation of that accounting practice, potential energy is actually part of the matter that is already counted in the rest mass of the material object whose forces are a potential source of kinetic energy.

This theory calls for a deeper explanation of how the matter appears both as a material object, with a definite location and rest mass, and at the same time as force field spread out in the space around that center of mass. We will consider such a theory later, but for now, we must simply recognize that the rest mass includes both forms of matter. And we can use the notion of gravitational potential energy to illustrate further the puzzling relationship between momentum and kinetic energy.

Gravitational forces exist as fields in which forces are exerted continuously over time and material objects change momentum continuously as they move through them. The way in which material objects interact by gravitational forces can be described as a conversion between potential and kinetic energy, and since such conversions are also a way of explaining the interaction of material objects by electric and magnetic forces, I will describe some of its features by considering what happens to a ball thrown upwards in a (nearly) constant gravitational field, such as near the surface of the earth.

The ball has an initial momentum when it leaves the hand that is proportional to its upward velocity. But since its momentum is constantly decreasing as the result of the constant downward gravitational force on it, there is a point at which the ball comes to a stop and starts falling again, after which its downward velocity increases until we catch it. The ball had kinetic energy when it left our hand, but at the top of its trajectory, it has lost all its kinetic energy. And by the time we catch it, the ball has regained kinetic energy. Since kinetic energy is a form of matter, it never simply goes out of existence or comes into existence, but merely changes form. It is converted into potential energy, which the ball has because it is located in a way that enables the gravitational force to accelerate it over some distance, that is, can acquire kinetic energy from those forces as the object moves through the gravitational force field. If we think of it ontologically, we see the ball losing kinetic matter as it rises, but since the distance across which the gravitational force can accelerate the ball increases, it gains potential energy (which increases the rest masses of both ball and earth). And when it falls, it loses potential energy (decreasing rest masses) and acquires kinetic energy. Since the ball has lost all its kinetic energy at the top of its trajectory, when it is at rest, its potential energy at that point must be equal to its kinetic energy at the beginning and end of its trip. The potential energy depends on two factors, the force exerted by the earth on the ball and the ball’s location in that force field. Both are needed to accelerate the ball and give it kinetic energy, and since the force is nearly the same at every location, the potential energy turns out to be proportional to the height to which it rises, that is, to the distance it can fall in the (constant) gravitational field.

This allows us to see, once again, the difference between momentum and kinetic energy. How much faster would we have to throw the ball upward in order for the point at which its stops and starts falling again to be twice as high? It is not necessary to double its velocity, as we would find if we tried. Instead, the initial velocity needs to be increased only by the square root of two (or about 1.4). The reason is that the ball consumes kinetic energy in rising to a certain height in the gravitational field, not momentum, and since kinetic energy varies with the square of the velocity, it is not necessary to double the initial velocity to double kinetic energy). (Likewise the time it takes will also increase only by a factor of the square root of two, since gravity changes its momentum at the same amount each unit of time and the amount of momentum to be changed is only increased by the square root of two.)

The conversion between kinetic and potential energy is basic to classical physics, though the quantities become more complex when we take into account that gravitational forces are not constant, but have a strength that varies inversely with the distance from the center of gravity. But we need not consider all the complexities of the quantitative relations (though these ontological causes must be able to explain them in the end), because we are merely trying to see what is involved in an ontological explanation of the basic laws of classical physics. We have seen how such ontological causes would make Newton’s laws of motion true, and spatiomaterialism is not trivial, like materialism, considering that it implies the existence of kinetic matter (and begins, at least, an explanation of the relationship between momentum and kinetic energy). The one form of matter that has not been described is electromagnetic waves, and that brings us to the explanation of Maxwell’s laws of electromagnetism.

Maxwell’s laws of electromagnetism.The other basic set of laws making up classical physics at the end of the 19th Century were Maxwell’s four laws of electromagnetism. They describe the electric and magnetic forces and how they interact, and these forces can be explained in much the same way as gravitation, that is, as a form of matter that coincides with space by being spread out spread out in space like a field, and yet contained in the rest mass of material objects with electric charges.

Electromagnetism is more complex than the gravitational force, because there are two forces, electric and magnetic, which interact with one another, and there are two opposite electric forces that material objects can have, positive and negative.

Maxwell’s great triumph was to show how the interaction of the electric and magnetic forces can couple them in a way that propagates both across space at a fixed velocity, that is as electromagnetic waves propagating at the velocity of light. Since electromagnetic waves exist independently of all the other forms of mass and energy (and, thus, the other three forms of matter, on this ontological account), there is less room for doubt about these forces being a form of matter.

It is now known that electromagnetic interactions mediate all the non-gravitational interactions among molecules, among atoms in molecules, and even between electrons and protons in atoms. Even the elastic collisions that we took for granted in discussing Newton’s laws of motion are mediated on the micro level by interactions involving both electric and magnetic forces among objects with electric charges. But all these interactions involve events with a unit-like nature which was unexplained until the discovery of quantum mechanics, and we will take them up later (in Change: Quantum mechanics.)

At this point, I will discuss aspects of the regularities described by Maxwell’s laws in an order that adds up to an explanation of electromagnetic waves, and then I will discuss how spatiomaterialism can explain such waves ontologically.

Electric charge. One of Maxwell’s laws describes the electric forces that can be exerted by material objects. When a material object has an electric charge, it exerts a radial force surrounding the center of rest mass whose strength declines with the square of the distance. This is like the force of gravity, except that the electric force acts on other objects because of their electric charges, rather than their mass. And unlike the gravitational force, the electric force can be either attractive or repulsive, depending on whether the other object has an opposite or same electric charge, respectively. The electric force can give such objects kinetic energy (or become another form of energy, such as an electromagnetic wave), and so it is counted as potential energy. But once again, the maximum potential energy is zero, making it a negative quantity when some of it has been consumed.

Spatiomaterialism can explain potential electrical energy ontologically as some of the matter that is counted in the rest masses of the material objects exerting the electric forces. Thus, when potential energy is consumed, the rest masses of the charged objects are less. If we think of the potential energy as a form of electromagnetic matter that is spread out in space around the objects with the electric charges, we can see why the quantity of potential energy varies with the matter.

Objects with opposite charges attract, and their potential energy is maximum when they are far apart from one another, because their electric fields more nearly approximate a spheres (of forces declining with the square of radius), which requires the maximum quantity of electromagnetic matter to constitute them. But when opposite charges are next to one another, their electric fields are mostly neutralized, and the electric field they jointly set up is deformed in a way that requires less electromagnetic matter. In this case, their total rest mass is less than if they were independent of one another.

Objects with like charges repel, and their potential energy is maximum when they are close to one another, because instead of neutralizing one another, their electric fields oppose one another. Though holding them together yields an electric force that is twice as strong as the radial force field they jointly set up, additional electromagnetic matter is required for the two charged particles to have a force repelling them from one another. In this case, their rest masses are greater than they would be if the objects were at a distance from one another.

In either case, in the equations describing these situations, the potential energy is represented as zero when it is maximum, and thus, what is actually a loss of rest mass, which comes from consuming potential energy and converting electromagnetic matter into other forms of matter, is counted as negative potential energy.

The electric field is also more complex than gravitation in another way because of its interaction with the magnetic force. It affects the motion of a charged object in an electric field. For example, in an electric field is set up by a material object too massive to move much, a charged object that is accelerated by it will increase its velocity not only in the direction of the force, but also in a direction perpendicular to both the electric force and the direction of its own motion in the electric field. That is the work of the magnetic force. The magnetic force on the charged object is a function of its velocity through the electric field as well as the strength of the electric field. This effect of electric forces is not mentioned in this first law, but is a consequence of another of Maxwell’s laws.

No magnetic charges. The second law holds that there is no material object with a magnetic charge, even though there are magnetic forces. A material object with a magnetic charge would have a radial force surrounding its center of rest mass which declines with the square of the distance. Instead, as it turns out, magnetic forces occur in fields in which they are all directed around a closed loop, such as a circle.

According to another law, as mentioned above, the magnetic force can arise because of the motion of a material object with an electric charge. For example, when electric charges are moving in a certain direction through space, they set up a magnetic field in which the magnetic forces are aligned in a circle around their direction of motion. (Such a circular field is set up even when the moving electric charges are neutralized locally by opposite charges, as in a wire in which a current is flowing, and the net strength of the electric force is not changing at any point in space in the surrounding space.)

Coupling of magnetic and electric forces. The two remaining aspects of the regularities described in Maxwell’s equations explain electromagnetic waves. One holds that a change in the magnetic field causes a circular electric force around the direction of the magnetic forces. The other holds that a change in the electric field causes a circular magnetic field around the direction of the electric forces. In both cases, the strength of the field being set up varies with how fast the first field changes (and thus indirectly on the strength of the forces). But the directions are reversed (so that an increasing electric force causes a magnetic force, while an increasing magnetic force causes a electric force in the opposite direction). Furthermore, the change in the strength of each force generates a force of the other kind that is related to it spatially in a certain direction, so that changes in the two forces are coupled as a wave that propagates across space at the velocity of light.

An impression of how electromagnetic waves propagate can be gathered by considering how the motion of electric charges generates them. Consider, for example, a current of electrically charged objects in a wire that is changing direction. The current sets up a magnetic force circling the wire, but as the electric charges slow down, the magnetic force declines (because the rate of change in location of the electric charges becomes lower). The decline in the magnetic force field causes an electric force that circles it. But the change in that electric force causes, in turn, a magnetic field around its direction, which is in the opposite direction of the first magnetic field. And the change in the second magnetic field then causes an electric field, this time in the opposite direction. And finally its change causes a magnetic field that is like the one caused by the electric charges in the wire, except that it is located a fixed distance away from the wire which depends on the velocity of light. Thus, the changes in the two forces are coupled in a way that propagates across space at the velocity of light as an electromagnetic wave. And a steady succession of such waves is generated as long as the current in the wire continues to oscillate. That is basically how antennas send electromagnetic waves.

Electromagnetic waves are a form of energy counted in the principle of the conservation of mass and energy, and though the quantitative details are not relevant here, we should consider what our working hypothesis implies about the nature of "electromagnetic matter." The matter involved in these waves is similar to the matter that makes up the electric field of a material object with an electric charge, except that in the electromagnetic wave, the electric force is changing and the changes couple it with a magnetic force that also changes. The forces interact in such a way that they go through complete cycles, putting them in a position to do the same thing over and over again. But the forces they generate are so related to one another in space that the wave moves across space over time at certain fixed velocity, that is, the velocity of light.

The matter constituting electromagnetic waves may not be as different from the electromagnetic matter constituting electric charges as this contrast makes them appear. According to current quantum theory, material objects with electric charges also have a spin angular momentum. Since that is a magnetic force, it suggests that the electric charge may actually be an electric force that is changing cyclically by somehow spinning around an axis. That possibility will lead us to speculate (when discussing quantum mechanics and the basic particles) that the opposite electric charges (positive and negative) differ from one another by being in opposite phases of their cycles wherever they are located in space.

Inherent motion in space. Maxwell deduced the velocity of light in a vacuum from measurable constants mentioned in his laws, and since classical physics assumed that space is absolute, it could hope to explain this implication as the result of electric and magnetic forces being exerted on an extremely elastic substance that was assumed to be at rest in absolute space. They called it the “luminiferous ether” (or “ether,” for short). Since the ether was supposed to be a kind of matter, it seemed plausible to explain the propagation of electric and magnetic forces mechanically, as an interaction between charged particles and the ether, on the model of waves of forces in ordinary material objects. That project did not work out, but that does not mean that space cannot be playing a similar role in the motion of electromagnetic waves.

In recognizing that space is a substance, spatiomaterialism departs from classical physics as well as from materialism. Though classical physics assumed that space is absolute, it did not take space to be a substance that could interact with bits of matter in any way other than providing all the locations where they are could move or be located. In particular, space was not supposed to affect the motion of bits of matter, at least, not in the way other bits of matter can. But since spatiomaterialism has independent reasons for believing in the existence of space as a substance enduring through time (that is, in addition to presentism, reasons deriving from the recognition of the validity of ontological-cause explanations and inferring to the best ontological-cause explanation of the natural world), it has no reason to doubt that space can interact with bits of matter in ways that are quite comparable to the interactions of bits of matter in space. Thus, spatiomaterialism can use space to explain the velocity of light without having to postulate the existence of the ether as an additional kind of matter that coincides with space. We can take talk about the ether to be referring to an aspect of space as a substance. That is what we will do by taking space itself to be the medium of light transmission.

To be the medium of light transmission, space must have an aspect by which it interacts with electric and magnetic forces and carries them across space as electromagnetic waves at a certain velocity. In order to explain how space does so, I will assume that there is an “inherent motion in space.” By “inherent motion,” I mean a further relationship among the parts of space, beyond the geometrical relations we have already assumed, which involves their endurance through time. We have assumed that the parts of space are particular substances, that is, so that each point has an existence that is distinct from all the others and each point endures, like any substance, through time, never coming into existence nor going out of existence. But since only the present moment exists, only one moment in the history of each part of space exists, and that moment in the history of all the parts of space always occurs at the same time. That is how these substances exist together as a world, and it is the wholeness of space that relates the bits of matter it contains as parts of the same world. This temporal aspect of the nature of the parts of space is the ontological foundation for a further relationship among the parts of space. What I am calling the "inherent motion of space" (as our substitute for the "luminiferous ether") is a spatio-temporal relationship among the parts of space.

Such a temporal aspect to space is not only plausible, but also required by the role of space in constituting what happens. If the parts of space did not have a spatio-temporal relationship to one another, they could not affect one another as time passes. Nor could they enable bits of matter to affect one another.

The geometrical relations among the parts of space explains which parts of space can be affected by any other given part, namely, those nearby, then those next to it, and so on. But in order for a change occurring at any one part of space to affect another part of space, the other part of space must change at a later moment. If the effect were immediate, the effect would not be distinct from the cause, and they could not act on one another like particular substances enduring through time. Space would interact with bits of matter as a whole. Thus, let us assume that the rate at which one part of space can affect another part of space as time passes is finite. That would be a maximum velocity by which one part of space can affect other parts of space. I call it the “inherent motion” in space in order to make clear that it is a temporal aspect of the nature of space as a substance.

I think of the "inherent motion" as a motion sweeping through every part of space at the same velocity, both ways in every direction possible in three dimensional space, at every moment. This is how space is an ontological cause, along with the nature of electromagnetic matter, of the velocity of light. That is, we can explain the motion of electromagnetic waves as bits of matter (or so-called “photons’) being carried along by the inherent motion. But there is an inherent motion, even when there are no photons. Indeed, it would be happening, even if there were no matter in the world. In other words, the inherent motion is an aspect of space as a substance.

The postulation of an inherent motion may seem ontologically excessive, since all we need to assume is that the parts of space are so related temporally, as well as geometrically, that there is a maximum rate at which it is possible for what happens to matter at one part of space to affect what happens to matter at another parts of space. Thus, it may be urged that the inherent motion is not real, but merely the velocity of possible effects across space. It is merely a spatio-temporal geometry about space, that is, a geometry describing how the present moment of any one part of space is related to the past or future moments of other parts of space because of the maximum velocity with which events can affect one another. Such an account, it could be argued, would be a better ontological explanation in the end.

Though a spatio-temporal geometry to space may be a sufficient ontological explanation, I will continue to speak of it as the "inherent motion in space." I can take this liberty, because I am not claiming that the more specific natures of matter and space that I am introducing in order to explain the truth of physics are the best possible spatiomaterialist ontological explanation of the basic laws of physics, only that they are a possible spatiomaterialist ontological explanation. That is all that is required for ontological philosophy to make the case for using spatiomaterialism as the foundation for its argument about necessary truths. And I allow myself the liberty of postulating an actual inherent motion in space, because that invokes an image (in rational imagination) that makes it easy to think about an aspect of the essential nature of space that will be central in the following explanation of the laws of contemporary physics. I find it preferable to “spatio-temporal geometry,” because talk of motion brings out vividly the temporal aspect of what might otherwise be seen as a static structure (such as spacetime in Einsteinian relativity). And it emphasizes that it is always happening everywhere in space, connecting the parts of space ontologically in a further way than merely having geometrical relations, a way that is central to the existence of causal connections among events in the world.

As it turns out, nothing turns on the difference between saying that space has a an inherent motion and saying that space has a spatio-temporal geometry, as long as we recognize that we are talking about an aspect of a substance that endures through time and has the opposite nature from matter. The motion of electromagnetic waves (or photons) is only one manifestation of this aspect of the essential nature of space. There will be several others as we proceed, and it will be a somewhat more complex aspect of space by the time we are through, variations in its velocity at different locations in space. It is easier to think about these ontological effects of space by thinking of space as having an inherent motion prior to the motion of photons, because the picture is spatial imagination is more concrete.

The the inherent motion in space is the medium of light transmission, and though it may also be called the "ether," as it was in Newtonian physics, it is ontologically important to keep in mind that it is an aspect of space. The ether was supposed to be an ethereal matter that is at rest everywhere in space, and no such thing is needed in a spatiomaterial world, because when space is a substance, it can interact with bits of matter in much the same way as other bits of matter.

It should be noted, however, that just as it made sense to speak of being at rest in the ether, it will make sense to speak of being at rest relative to the medium of light transmission. In either case, it is the reference frame in which the one-way velocity of light is exactly the same both ways in every direction in three dimensional space. It was assumed in Newtonian physics that being at rest in the ether would be at rest in absolute space, because they assumed that the ether was at rest in absolute space. Though we also assume that there is a reference frame that is at rest relative to the light medium, we will not assume that it is at rest in absolute space, because in order to explain ontologically the truth of the general theory of relativity, we will have to assume that the light medium itself can have a velocity in space. That will be to hold that that inherent motion in space can have a different velocity at different locations. But if you prefer, such talk can always be translated into talk about the spatio-temporal geometry of space as a substance enduring though time.

The basic laws of classical physics can, in sum, be explained ontologically by postulating various forms in which matter can coincide with space as a substance. Those forms of matter are material objects with rest mass, kinetic matter, gravitational matter, and electromagnetic matter (including both matter as electric and magnetic forces and as electromagnetic waves). And they explain the truth of the laws of classical physics in the sense that a world made of such substances enduring through time has aspects (properties, relations and regularities about change) that correspond to those laws.

That is, the laws of classical physics are true because they correspond to an aspect of the world that has been constructed from our assumptions about the basic nature of substances, about space and matter as the two opposite kind of basic substances that make up the world, and about the specific forms of matter that coincide with space. There is, therefore, one way, at least, that a spatiomaterialist ontology can make its basic laws true, which shows that spatiomaterialism is possible, as far as classical physics is concerned.

Thus, we have laid the foundation we will need in order to explain the truth of the basic laws of contemporary physics ontologically. The first step in that project has already been made by postulating an inherent motion in substantival space to explain the velocity of light ontologically. In assuming that light has a medium through which it is transmitted, it may seem that we are resurrecting the "luminiferous ether" of Newtonian physics. But if so, it is no longer a strange form of ethereal matter at rest in space, but an aspect of space itself. Space itself is the medium of light transmission.

Contingent laws: Contemporary physics.In the early 20th Century, revolutions in physics have made it seem impossible for spatiomaterialism to explain the basic laws of physics ontologically. There were two revolutions, Einstein’s two relativity theories and quantum mechanics. The first led to the belief in spacetime, and the second made it seem that processes at the micro-level are indeterministic. These new theories were irresistible in physics, because they were justified by the empirical method in the same way as Newtonian physics had been. They were inferences to the best efficient-cause explanations, where the best depends heavily on making surprising, quantitatively precise predictions that turn out to be true when measurements are made. And both revolutions have been extremely fruitful, leading to surprising predictions in new fields.

Two theories are involved in the Einsteinian revolution: the special theory of relativity, which covers phenomena that occur in material objects with velocities approaching that of light, and the general theory, which is a more accurate account of gravitational phenomena. Together with quantum mechanics, the special theory led to quantum field theory, a more accurate account of electromagnetism, which included the discovery of spin and positively charged electrons. As a gauge field theory, quantum electrodynamics became the model for theories about the two short range forces, the so-called weak and strong (or color) forces, which are responsible for the composition of particles in ordinary material objects, and that has exposed more basic particles of nature, such as quarks and neutrinos. Together with the observation that the universe seems to be expanding (Hubble's law), the general theory is now used to support the big bang theory about the origin and expansion of the universe. In sum, our understanding of every kind of physical phenomenon has been radically enriched by these two revolutions in physics.

There is one way, however, in which these two revolutions do not fit well together. It is often characterized as the main theoretical problem of contemporary physics. Einstein’s general theory of relativity explains gravitation, one of the four basic forces, but it is mathematically quite different from the theories describing the other three forces (electromagnetism, the color force and the weak force). The latter three are formulated as gauge field theories, making it possible to fit them together mathematically, but no one has found a simple way of connecting them with Einstein’s general theory of relativity. Attempts to connect them have led some physicists to believe that there are ten or more dimensions to space!

Notice that this theoretical problem in contemporary physics is basically a mathematical problem. It derives from the so called "holy grail" of physics, which is to discover a single law from which all the laws of physics, describing all the basic forces, can be derived. But the incompatibility between quantum theory and the theory of gravitation is very likely intractable as a mathematical problem.

Physics is crying out for a new approach. That is what ontological philosophy supplies. The solution to the main problem of contemporary physics is an extra benefit of its spatiomaterialist interpretation of contemporary physics.

Each of the basic revolutions of contemporary physics poses, however, a challenge to spatiomaterialism all by itself.

Einstein’s two relativity theories pose a challenge to ontological philosophy, as we have already seen, because they seem to describe a world in which space and time are not absolute. Realism about Einsteinian relativity entails the belief in spacetime, which puts time ontologically on a par with space: each moment in time is supposed to exist alongside every other moment in time, just as each point in space exists alongside every other point in space, as equal parts of an eternal four-dimensional world. But the belief in spacetime is incompatible with spatiomaterialism, because spatiomaterialism holds that only the present moment exists and takes space to be one of two opposite kinds of substances that endure through time. Thus, unless there is a way that Einstein’s special and general theories of relativity can be true in a world where space and time are absolute, ontological philosophy cannot use spatiomaterialism as the foundation for its arguments about what is necessary. Showing how the belief in spacetime could be replaced in a spatiomaterial world was one of the mortgages we took out in order to make this argument, and now the time has come to pay it off.

Quantum theory however, may also seem incompatible with spatiomaterialism. In addition to its apparent denial of determinism, it seems to deny that physical processes are constituted by material substances that coincide with space. Quantum mechanics is often interpreted, at least, as denying that the smallest entities have definite locations and as implying that they behave in ways that are incompatible with the principle of local motion and local action.

Quantum mechanics is less challenging than Einsteinian relativity, because the received interpretation of it (the so-called “Copenhagen interpretation, due mainly to Bohr) is more like skepticism about ever knowing the real nature of the smallest bits of matter than a generally accepted ontological belief about what exists on the micro-level that is incompatible with spatiomaterialism. The belief in spacetime is incompatible with the belief in absolute space and time.

It is possible, however, for spatiomaterialism to explain the truth of both theories. What is more, by explaining their truth ontologically, it solves the problem about how gravitation is related to the other three forces of nature. This ontological solution to the basic theoretical problem of contemporary physics will also provide the foundation for more speculative suggestions about cosmology, both the basic particles recognized by high energy physics and about the origin of the large scale structure of the universe.

Relativity theories. The two theories involved in Einsteinian revolution will be discussed in sequence. The notion of spacetime was introduced with the special theory of relativity as a way of explaining measurements made from objects with very high relative velocities, and Einstein used it as the basis for his explanation of gravitation. In a parallel way, the ontological explanation of spacetime in the special theory of relativity will be the foundation for the ontological explanation of the role of spacetime in the general theory of relativity.

In the case of Einstein’s special theory of relativity, it may not be surprising that it is possible for spatiomaterialism to explain its truth, for even Einsteinians admit that the empirical implications of Einstein’s theory could be explained on the assumption that space is absolute. It is just a matter of assuming that one of all possible inertial reference frames is at absolute rest and explaining the appearance that it is not different from the others on the assumption that absolute space causes certain distortions in material objects that move through it. Such a theory is possible, and it was begun, at least, by Newtonian physicists before Einstein first published his special theory of relativity.

The ontological explanation of Einstein’s general theory of relativity may be more surprising, because contemporary physicists apparently do not even suspect that it is possible to understand the gravitational phenomena discovered by Einstein on the assumption that space and time are absolute. The universal acceptance of the special theory of relativity and its notion of spacetime as a description of the nature of space and time has kept physicists from even considering a very simple, intuitively satisfying, ontological explanation of gravitation.

The spatiomaterialist special and general theories of relativity that result are not ontologically necessary truths, according to ontological philosophy, because they do not follow from spatiomaterialism, but rather depend on what has been discovered empirically about what happens in the world. All that needs to be shown is that it is possible for Einstein’s two theories to be true in a spatiomaterial world.

Once the laws of physics are explained ontologically, the additional assumptions that must be made about the nature of matter and space in order to explain them will be incorporated into the foundation of ontological philosophy as a way of explaining ontologically other aspects of the world, such as the global regularities. That is how we incorporate the laws of physics into spatiomaterialism. But since those further explanations will depend on the more specific natures of matter and space assumed here in order to explain the truth of classical and contemporary physics, their ontological necessity will be only conditional. They hold only of all possible spatiomaterial worlds like ours, that is, in which the laws of physics are true.

As it happens, however, the spatiomaterialist ontological explanation of the truth of classical physics together with its explanation of quantum mechanics seem to entail the ontological assumptions that have to be made in order to explain the truth of the special theory of relativity. If so, the regularities described by Einstein's special theory of relativity have a deeper ontological explanation, even if they are not unconditionally ontologically necessary.

It should be mentioned, however, that the explanation of the global regularities to be given under Change does not depend on this ontological explanation of the truth of contemporary physics. Given that space is a substance, they depend only on matter obeying the regularities described by the laws of contemporary (and classical) physics. Though we shall make further assumption about the nature of space and matter in order to explain ontologically the truth of quantum mechanics, the basic objects of physics, and the origin of the universe, they are required only to show the possibility of spatiomaterialism. They are not relevant in explaining the global regularities.

Einstein’s special theory of relativity. To explain how Einstein’s special theory of relativity can be true in a spatiomaterial world is to show that the regularities it describes can be constituted by substances of the kinds postulated by spatiomaterialism, that is, that it can correspond to aspects of space and matter as substances enduring through time.

In addition to the assumptions already made about the forms of matter and the inherent motion in space in order to explain the truth of classical physics ontologically, further assumptions about the nature of space and matter will be needed to explain special relativity. They are basically distortions of the kind that Lorentz described in fast moving material objects before Einstein’s first paper (time dilation and length contraction, though there must be compensating changes in masses and longitudinal forces as well), though something more must be said about the synchronization of clocks at a distance in order to explain the truth of all the predictions of the special theory.

In the first section, A Brief History of the Special Theory, I will give a brief history of how Einstein’s special theory of relativity was accepted in order to show that these distortions in fast-moving objects provide everything required to explain why Einstein’s theory is true.

Lorentz first described these distortions in order to explain the surprising results of the Michelson-Morley experiment, which established that it was not possible to measure the absolute rest and motion of a material object by measuring the velocity of light relative to it. But Lorentz’ theory was rejected in favor of Einstein’s special theory of relativity, which took a radically different approach. That was not a mistake within physics, because Einstein’s theory was superior according to the empirical method of science of physics (that is, inferring to the best efficient-cause explanation, or by the criteria of predicting and controlling what happens). But Einstein’s theory is not the best ontological-cause explanation of the phenomena. Indeed, as we shall see when Einstein’s premises and conclusions are explained ontologically, even its apparent superiority as an efficient-cause explanation rests on an illusion.

In the second section, The Lorentz Distortions, I show how Lorentz explained the undetectability of absolute motion or rest and the other distortions that are required for all the laws of physics to hold the same way on a moving inertial reference frame.

In the third section, The Symmetry of the Lorentz Distortions, I show how Einstein's definition of simultaneity at a distance combines with the Lorentz distortions to explain the puzzling symmetry about any pair of inertial reference frames that is emphasized by Einstein in calling his theory a theory of "relativity." This symmetry implies that inertial reference frames are empirically equivalent as far as experiments that observers on each frame can perform on one another are concerned, and as we shall see, it is just an appearance that depends on the mis-synchronization of clocks on inertial frames according to Einstein's definition and how that combines with the Lorentz distortions.

In the fourth section, The Ontological Necessity of the Lorentz Distortions, I will argue that although the Lorentz distortions are new laws of physics, they have a deeper explanation given our ontological explanation of the laws of classical physics and a plausible assumption about the nature of material objects (which will be justified later as a way of explaining the truth of quantum mechanics and what physics now knows about the microstructures of material objects). But given our assumption about space being the medium of light transmission (that space has an inherent motion), that conception of the nature of material objects will make it possible to show that the Lorentz distortions are not merely ad hoc assumptions made in order to retain the belief in absolute space, as is often charged, but rather have a necessity about them.

In the end, therefore, we will see that, in making the argument for his special theory of relativity, Einstein did not discover anything about the natural world that cannot be explained by an ontology, like spatiomaterialism, that implies that space and time are absolute. But what is more, spatiomaterialism explains special relativity in a way that removes all the mysteries about spacetime and makes it possible to explain ontologically, as well, why Einstein’s general theory of relativity is true. That will solve the main theoretical problem of contemporary physics, the relationship between gravitation and the other basic forces of nature, and it also has some surprising implications for cosmology.

A Brief history of Einstein’s special theory of relativity.The main conclusions of Einstein’s special theory of relativity are the Lorentz transformation equations. They are called the “Lorentz transformation equations,” because they had already been discovered, before Einstein’s first paper, by H. A. Lorentz, taking a Newtonian approach. That is where I will pick up the story about the Einsteinian revolution in physics, since spatiomaterialism is merely following in the footsteps of Lorentz. What I will call the four “Lorentz distortions”are sufficient to explain all the of the predictions by which Einstein’s special theory of relativity has been confirmed.

Lorentz. By 1887, some eighteen years before Einstein’s paper, Michelson and Morley had made experiments that showed that light has the same velocity relative to any object, regardless of its own motion. What made their result puzzling was the Newtonian assumption that the medium in which light propagates is a “luminiferous ether,” a very subtle kind of material substance that was supposed to be at rest in absolute space. Given that the velocity of light is everywhere the same relative to absolute space, they expected that the velocity of light, as measured from a material object, to vary with that object’s own velocity in absolute space—just as the velocity of ripples propagating in a pond arrive faster (or slower), when a boat is moving toward them (or away from them).

Michelson and Morley used an interferometer, which compares the two-way velocities of light in perpendicular directions; that is, light is reflected back from mirrors in perpendicular directions and the signals are compared to see if one is lagging behind the other. They made measurements at various points in the Earth’s orbit around the sun, where the Earth should have different velocities in absolute space. On a moving object, the time it takes for light to travel both to and from a distant mirror in the direction of absolute motion should be different from the time it takes to travel an equal distance in the transverse direction.xvii The margins of error were small enough, given the velocity of light and the velocity of the Earth in its orbit around the sun, that it should have been possible for their interferometer to detect absolute velocity. But Michelson and Morley failed to detect any difference at all in the time it took light to travel the same distance in perpendicular directions. Absolute motion could not be detected.

Length contraction. The Michelson-Morley result was surprising, but even before Einstein published his special theory in 1905, Lorentz had proposed a Newtonian explanation of it. Lorentz showed, in 1895, that their result could be explained physically, if the motion of such an apparatus in absolute space caused its length to shrink in the direction of motion as a function of its velocity by a factor of . Lorentz argued that this length contraction is a real physical change in the material object that depends on its motion relative to absolute space.

The equation was L=Lo, where Lo was the length at absolute rest. The shrinkage had been proposed independently by George F. Fitzgerald in 1889 and hence became known as the “Lorentz-Fitzgerald contraction”.xviii

Lorentz tried to explain the length contraction physically, as an effect of motion through a stagnant ether on the electrostatic forces among its constituent, charged particles.xix But he could just as well have taken it to be a law of physics, making the Lorentz-Fitzgerald contraction the discovery of a new, basic physical law. (An ontological explanation of it will be suggested in the last section of this discussion of the special theory of relativity.)

Lorentz also described the length contraction as a mathematical transformation between the coordinates of a reference frame based on the moving material object and the coordinates of a reference frame at absolute rest. Lorentz started with the Galilean transformation by which Newtonians would obtain the spatial coordinates used on an object in uniform motion in the x-direction, or x’ = x - vt, and combining that with the length contraction he had discovered, he came up with the transformation equation, for obtaining the spatial coordinates on the moving material object.xx

Time dilation. There is, however, another distortion that material objects undergo as a function of their absolute motion. That is a slowing down of clocks (and physical processes generally) at the same rate as the length contractions, or the so-called "time dilation," which took somewhat longer for Lorentz to discover.

The Galilean transformation for time in Newtonian physics is simply t = t' , because Newtonian physics assumes that time is the same everywhere. But by using transformation equations to describe the distortions in material objects, Lorentz found that he had to introduce a special equation for transforming time: t’ = t - vx/c2 (Goldberg, p. 94). The new factor in the transformation equation, vx/c2, implied that time on the moving frame varies with location in that frame. Lorentz called it "local time," but he did not attribute any physical significance to it. "Local time" is not compatible with the belief in absolute space and time, and Lorentz described it as “no more than an auxiliary mathematical quantity” (Torretti, p. 45, 85), insisting that his transformation equations were merely “an aid to calculation” (Goldberg, p. 96).

The slowing down of physical processes is called “time dilation.” Lorentz discovered this distortion by tinkering with various ways of calculating the coordinates used on inertial reference frames in relative motion. Thus, it is natural to describe time dilation as the slowing down of clocks on the moving reference frame. It was included in the final version of Lorentz's explanation, now called the “Lorentz transformation equations.” (Lorentz 1904) Those equations contained not only the length contraction and transformation for “local time”, but also the implication that clocks on moving frames are slowed down at the same rate as lengths are contracted (that is, ). The final Lorentz equation for time transformation included both the variation in local time and time dilation: .

Though Lorentz took the distortions that he discovered in fast-moving material objects to be laws of nature, he did not think that they were basic. He thought they were effects of motion on the interactions between electrons and the ether which could be explained by his electronic theory of matter, and he saw explaining this effect as the the main challenge to Newtonian physics. The transformation equations themselves never seemed puzzling to Lorentz, because he never took them to more than just a mathematical aid to calculation.

Poincaré. H. Poincaré thought he saw more clearly what Lorentz had discovered than Lorentz himself. As early as 1895, Poincaré had expressed dissatisfaction with Lorentz’s piecemeal approach, introducing one modification of the laws of Newtonian physics after another in order to account for different aspects of the phenomenon discovered by Michelson and Morley. Instead of such ad hoc modifications, he urged the recognition of what he called a “principle of relativity” to cover all the phenomena involved in fast-moving objects. As Poincaré put it in 1904, the principle of relativity requires that “the laws of physical phenomena should be the same for an observer at rest or for an observer carried along in uniform movement of translation, so that we do not and cannot have any means of determining whether we actually undergo a motion of this kind” (from Torretti, 83).

A principle of relativity like this had, in effect, been affirmed by Newton himself, when he admitted that his laws of motion depend, not on the absolute velocities of material objects, but only on their relative velocities. That is, Newton had already denied that absolute rest could be detected by mechanical experiments. It seemed that absolute motion could be detected only when Maxwell had discovered that light could be explained as an electromagnetic wave. Thus, Poincaré saw Lorentz's discovery of distortions in fast-moving material objects as a way of extending Newton’s principle of relativity to cover electromagnetic phenomena.

Understanding how the undetectability of absolute motion could be a result of the distortions that Lorentz had discovered, he referred to Lorentz theory as “Lorentz’s principle of relativity” even after Einstein had published his special theory and Lorentz himself was attributing the principle of relativity to Einstein (Torretti 85, Goldberg 212, and Holton 178). Indeed, Poincaré joined Lorentz in the attempt to explain the Lorentz distortions by the motion of material objects through absolute space, also expecting to find their cause in the dynamics of electrons; he also thought that motion through the ether caused material objects to shrink in the direction of motion and natural clocks to slow down by the exact amount required to mask their motion, as implied by Lorentz’s transformation equations (Goldberg 94-102, Torretti 38-47). Furthermore, Poincaré apparently thought that what Lorentz said about those equations in his 1904 work answered his own demand that it be a “demonstration of the principle of relativity with a single thrust” (Goldberg 214-15).

Lorentz's explanation of the distortions was not, however, a complete explanation of the principle of relativity. There are really two quite different aspects of the phenomenon described by the principle of relativity, and Lorentz had explicitly explained only one of them.

What Lorentz’s electron theory of matter (and Poincaré’s own refinements of it) explained physically were the Lorentz distortions in material objects with absolute velocity. That explained the negative outcome of the Michelson-Morley experiment: the contraction of lengths in the direction of motion and the slowing down of clocks as a function of motion through absolute space does make it physically impossible to detect absolute motion on a moving object by measuring the velocity of light relative to it. And that is one way in which inertial reference frames are empirically equivalent, because it holds of measurements made using any material object in uniform motion as one's reference frame, regardless of its motion through absolute space.

But there is more to the principle of relativity than explaining the null result of the Michelson-Morley experiment. The transformation equations that Lorentz constructed to describe the effects of absolute motion on material objects predict the outcomes of other experiments, such as attempts to measure directly the lengths of high-velocity measuring rods and the rate at which high-velocity clocks are ticking away. Though such experiments are more difficult to perform, they are conceivable, and Lorentz's equations do make predictions about them: moving measuring rods will be shrunken in the direction of motion and moving clocks will be slowed down. That suggests another way of detecting absolute motion. One might compare measuring rods or clocks that are moving at a whole range different velocities with one another and take the one with the longest measuring rods and quickest clocks to be closest to absolute rest. Hence, the principle of relativity would be false.

It is not possible, however, to detect absolute rest in this way, and as it happens, its impossibility is also predicted by Lorentz's theory, because he formulated his description of the Lorentz distortions in terms of transformation equations. Transformation equations are equations for transforming the coordinates obtained by using one material objects as a frame of reference into the coordinates obtained by using another material object as a frame of reference, and to be consistent, they must work both ways. That is, it must be possible to obtain the original coordinates by applying the transformation equations to the transformed coordinates. Thus, whatever distortions observers at absolute rest may find in material objects with a high absolute velocity will also be found by observers in absolute motion in material objects that are at absolute rest.

The recognition that Lorentz's theory, being formulated in terms of transformation equations, implied that all such inertial reference frames are empirically equivalent is presumably what led Poincaré to proclaim that Lorentz had finally explained the truth of the principle of relativity. Absolute rest and motion cannot be detected from any inertial reference frame.

Lorentz's theory was not, however, an adequate explanation of the principle of relativity, for there is still something puzzling about the empirical equivalence entailed by the symmetry of the Lorentz transformation equations.

Lorentz meant his transformation equations to be a way of describing the length contraction and time dilation in material objects with absolute motion, for that would explain the Michelson-Morley experiment, that is, why absolute motion cannot be detected by measuring the velocity of light in different directions. But since the transformation equations describe a symmetry between the members of any pair of inertial reference frames, they imply that observers using a fast-moving material object as the basis of their reference frame would observe a length contraction in measuring rods that were at absolute rest and a time dilation in clocks at absolute rest. That makes it impossible to detect absolute rest or motion by comparing different inertial reference frames with one another. But it is puzzling, because it is hard to see how both views could be true at the same time, that is, how two measuring rods passing one another at high velocity could both be shorter than the other and how two clocks passing by one another could both be going slower than the other.

In other words, Lorentz's theory does not really give a physical explanation of what Poincaré called the "principle of relativity." What entails the truth of the principle of relativity is the description of the Lorentz distortions in terms of transformation equations; the inability to detect absolute rest and motion by comparing inertial frames with one another comes from the symmetrical relationship that transformation equations represent as holding between the members of any pair of inertial reference frames. That symmetry is not physically possible, at least, not in the sense of "physical" that Lorentz had in mind when he tried to explain the distortions as occurring to material objects because of their motion in absolute space. If inertial frames are material objects in absolute space, then their measuring rods cannot both be shorter than the other and their clocks cannot both be slower.

As we shall see, what enables Lorentz's transformation equations to predict the symmetry of distortions is the "local time" factor in the time equation, vx/c2, which Lorentz insisted was just an "aid to calculation." It represents the readings that would be given by clocks on a moving reference frame that have been synchronized by using light signals between them as if they were all at absolute rest, that is, on the assumption that the one-way velocity of light is the same both ways along the pathway between any two clocks (as required by Einstein's definition of simultaneity at a distance). That assumption is false, as Lorentz understood these phenomena, and clocks on the moving inertial frame would be mis-synchronized. It can be shown, as we shall see, that this way of mis-synchronizing clocks on a moving frame combines with the Lorentz distortions that the moving frame is actually suffering to make it appear that its own Lorentz distortions are occurring in the reference frame at absolute rest (or moving more slowly). This is a physical explanation, given how the other frame's measuring rods and clocks are measured. But it is an explanation of the principle of relativity that reveals it to be the description of a mere appearance. Though there is an empirical equivalence among inertial frames, a physicist who accepted Lorentz's Newtonian assumptions would insist that it has a deeper physical explanation.

It was not Lorentz, however, but Poincaré who declared that Lorentz had explained the truth of the principle of relativity, and Poincaré's acceptance of Lorentz's explanation as adequate may have been colored by his own philosophical commitment to conventionalism. Poincaré viewed the choice between Euclidean or non-Euclidean geometry as conventional, and he argued that convention is also what raised inertia and the conservation of energy to the status of principles that could not be empirically falsified. Poincaré's acceptance of the principle of relativity should probably be understood in the context of this more or less Kantian skepticism about knowing the real nature of what exists. Considering how the standard of simultaneity at a distance varies from one inertial reference frame to another (depending on the "local time" factor in the Lorentz transformation equations), the principle of relativity could also be seen as a conventional truth.

Poincaré's pronouncement that Lorentz's theory had explained the principle of relativity could not have set well with Lorentz himself. Lorentz may have continued to call it "Einstein's principle of relativity" because he realized that it was not explained by his theory about how spatial and temporal distortions are caused in material objects by their absolute motion. What is responsible for the principle of relativity is the symmetry in pairs of inertial frames entailed by his equations being transformation equations. If the distortions didn’t hold symmetrically in any pair inertial frames, it would be possible to detect absolute rest and motion. But to my knowledge, Lorentz never argued explicitly that what he called "local time" on the moving material object (that is, vx/c2 in the time equation) represents a mis-synchronization of clocks on the moving frame that causes the moving frame's own Lorentz distortions to appear to be occurring in the other inertial reference frame.

The Newtonian explanation of all the relevant phenomena did not, therefore, have an adequate defender. Lorentz was more concerned to find an adequate physical explanation of the distortions he had discovered in material objects, and Poincaré was more interested in defending conventionalism. That is the Newtonian context in which Einstein's special theory of relativity won the day.

Einstein. Einstein took a dramatically different approach from both Lorentz and Poincaré. Instead of taking the principle of relativity to be an empirical hypothesis that could be explained physically by deeper, Newtonian principles, or as a conventional truth, Einstein raised the principle of relativity to the status of a postulate, which was not to be explained at all, but rather accepted as basic and used to explain other phenomena (Zahar 90-2). The mathematical elegance of Einstein's explanation of these phenomena is stunning. From the premise that all inertial reference frames are empirically equivalent, he derived a description of how two different inertial reference frames would appear to each other; that is, he deduced the Lorentz transformation equations.

Einstein's new approach can be seen most clearly by considering the structure of his argument. It is represented below in a diagrammatic form.

Einstein's Premises: | The Principle of Relativity | The laws of nature apply the same way on all inertial frames.
| The Light Postulate | The velocity of light is the same on all inertial frames.
| The Definition of Simultaneity  at a Distance | The local event halfway through the period required for light to travel to the distant event and back is simultaneous with the distant event.
Einstein's Conclusions: | To obtain the second frame's coordinates from the first frame: | To obtain the first frame's coordinates from the second frame:
Lorentz transformation equations      (kinematic phenomena) | [picture] | [picture]
Relativistic increase in mass      (dynamic phenomena) | [picture] | [picture]

The assumption that inertial frames are all empirically equivalent takes the form of three premises in Einstein’s argument: the Principle of Relativity, the Light Postulate, and Einstein's Definition of Simultaneity at a Distance (see table). Einstein's principle of relativity holds, with Poincaré, that the laws of nature hold in the same way on every inertial reference frame. That allowed Einstein to assume that Maxwell's laws of electromagnetism hold universally, and he considered what would be true of two different inertial frames in the same world. But in order to deduce the Lorentz transformation equations, Einstein also had to assume that that the velocity of light is the same relative to every inertial frame (the light postulate) and, accordingly, that simultaneity at a distance is defined on each reference frame as if the velocity of light is the same both to and back from a distance object.

What Einstein deduced from these premises are the “Lorentz transformation equations,” that is, equations for transforming the coordinates of any given inertial reference frame into those of any other.

The Lorentz transformation equations imply that any material object moving relative to any other inertial frame at a velocity approaching that of light will appear to suffer the Lorentz distortions: its clocks (and all physical processes) will be slowed down, and its measuring rods (and all material objects) will be shortened in the direction of its motion—both by the same amount, , which is a function of its velocity in the observer’s reference frame.

Einstein also inferred from these kinematic distortions and his principle of relativity that the mass of objects moving in an inertial frame increases at the same rate, making three distortions altogether. That dynamical implication is the source of Einstein's most famous equations, E = mc2.

It should be emphasized that there are really two sets of transformation equations. It may not seem that way, because Einstein's conclusion is often stated as just one of the two sets of equations listed above, making it look mathematically simpler. But that formulation overlooks a mathematical detail and thereby obscures what Einstein's conclusion is about.

Though the Lorentz transformation is exactly the same both ways between the members of any pair of inertial reference frames, it requires two, non-identical sets of transformation equations, because their relative velocity has the opposite sign for each observer. That is, the two coordinate systems are set up so that their origins coincide when t = 0 and t' = 0, and since they are moving in opposite directions, the relative velocity is v for one of them and -v for the other. Thus, in order for the transformation to be symmetrical, one set of transformation equations has to have the opposite sign for the second factor in the numerator of the equations for space and time.

Since this seems to be a mere technicality, the conclusions of Einstein’s argument are usually represented as a single set of Lorentz transformation equations (the first set in the above table). Duplication is avoided by introducing a special mathematical symbol to make the single set of equations represent both transformations in any pair of inertial frames. Thus, Einstein's conclusion seems more like just another universal law of nature. But this is just homage to the Pythagorean ideal of mathematical simplicity, which obscures the fact that Einstein's theory is, in the first instance, about the symmetry that holds between the members of every pair of inertial frames.

It should also be emphasized that Einstein's theory is about how reference frames are related, and only indirectly about the material objects on which they are based. Though it does have implications concerning the relationship between material objects with a high relative velocity, that relationship is described by way of a mathematical transformation that holds between the reference frames based on them.

Inertial reference frames are based on material objects that are not being accelerated, and what makes the material object a reference frame is that it is used as the basis for a coordinate system by which the locations and times of events throughout the universe can be measured. (For this purpose, it is useful to think of an inertial reference frame as a grid of rigid bars extending wherever needed in space with synchronized clocks located everywhere.)

Notice that Einstein's three premises are all about reference frames based on material objects. Indeed, his definition of simultaneity prescribes how clocks must be synchronized to set up such a reference frame. The light postulate makes explicit the assumption about the velocity of light on which his definition of simultaneity is based. And the principle of relativity states that all the laws of physics will hold the same way within that reference frame as every other one, that is, will make correct predictions about what happens in that reference frame.

Einstein derives conclusions from his premises by assuming that there are two different inertial reference frames in the world and figuring out how they must appear to one another. Since his premises are about their reference frames, it is hardly surprising that his conclusion is about a mathematical transformation between their coordinates.

Indirectly, however, Einstein's conclusion is a description of how material objects with different constant velocities are related to one another as parts of the same world, since the reference frames in question are based on material objects. But to see Einstein's conclusion as a description of how material objects are related in space is to take Lorentz's approach. For Lorentz, these same transformation equations were just a mathematically convenient way of describing from the absolute frame the spatial and temporal distortions that occur in material objects with a high velocity in absolute space.

By calling his argument a theory of relativity, Einstein emphasized that his theory is about the empirical equivalence of all inertial reference frames, not the relationship between the material objects on which they are based. Observers on each inertial reference frame have their own view of the relationship between the material objects involved, but they are different views, and it is their views that are related by the Lorentz transformation equations. The symmetry of the relationship between their reference frames is what is crucial for Einstein, because that is what rules out any way of detecting absolute rest or motion by comparing inertial frames to one another and ensures that there is nothing to distinguish one inertial frame from another except their velocities relative to one another.

The Lorentz distortions in material objects are, however, a consequence of the Lorentz transformation equations that Einstein deduced. And if one does follow Lorentz, interpreting them as a way of describing the material objects on which the inertial reference frames are based, then the Lorentz transformation equations lead to paradoxes, as I have already suggested. Those equations imply that observers using any given inertial reference frame will find the Lorentz distortions occurring in the material objects on which the other inertial reference frame is based, and thus, the symmetry of the transformation for any pair of inertial frames leads to paradoxes.

Consider two inertial frames in motion relative to one another. From the first frame it appears that clocks on the second frame are slowed down. That would make sense, if from the second frame, it appeared that first-frame clocks were speeded up. But special relativity implies that it also appears from the second frame that clocks on the first frame are slowed down. That is, the distortions are symmetrical on Einstein’s theory, not the reverse of one another, as one might expect. And if the Lorentz distortions are really symmetrical, it is inconceivable that the two inertial frames are just material objects moving relative to one another in absolute space, because in absolute space, there can’t be two clocks next to one another both of which are actually going slower than the other. If one assumes that Einstein's theory is describing material objects, one must give up the assumption that those objects are located in absolute space. They are, of course, parts of the same world, but they must be related to one another in some other way.

The same problem arises from the symmetry of the length contraction and relativistic mass increase, for there cannot be two measuring rods passing one another in space that are both shorter than the other. Nor can there be two material objects both be more massive than the other. It is simply not possible for material objects located in absolute space.

None of this should be a surprise, however, because even the Light Postulate itself is incompatible with absolute space (or at least, with the assumption that light has a fixed velocity relative to absolute space). Though Newtonian physics had taken absolute space to contain the medium in which light propagates, Einstein assumed that the velocity of light relative to every object is the same, regardless of their own velocities relative to other objects in the world. Thus, Einstein held that the velocity of light would be the same in both members of any pair of inertial frames. This is not possible, if electromagnetic waves propagate through (an ether in) absolute space, like waves in water, for the motion of an object through waves propagating in space would change the velocity of those waves relative to the object—just as the motion of a row boat through ripples propagating in a pond changes the velocity of those ripples relative to the boat.

Taken as a description of the relationship between material objects in space, therefore, Einstein's special theory of relativity leads to paradoxes. But Einstein was not discouraged by these paradoxes. He was not thinking of inertial reference frames as material objects that are related in space, that is, in absolute space, or a space that is the same for both material objects. He was making a more abstract, mathematical argument and, in the process, giving physics a new standpoint from which to explain all physical processes.

That Einstein's basic approach is different from Lorentz's can be seen in what made Einstein curious about these phenomena in the first place. It was not the Michelson-Morley experiment, but rather something peculiar about the connection between classical mechanics and Maxwell’s theory of electromagnetism (Zahar 99-100). Einstein realized that even though Maxwell’s theory was standardly interpreted as referring to absolute space, absolute space was not needed in order to explain electromagnetic phenomena. For example, a conductor moving through a magnetic field at absolute rest moves electrons exactly the same way as if it were at absolute rest and the magnetic field were moving. That is what suggested the principle of relativity to Einstein, and though from it he derived the same transformation equations that Lorentz had proposed in 1904, Einstein claimed not to know about Lorentz's 1904 work.xxi

By raising the principle of relativity to the status of a postulate, Einstein was assuming, in effect, that the deepest truth that can be known about the nature of space and time is that inertial frames are all empirically equivalent. And by relying on the predictions of measurements derived from that principle to justify his theory, Einstein had the support of the positivists, who dominated philosophy of science at that time. Indeed, Einstein admits to having been influenced by Ernst Mach at the time of his first paper on special relativity. To positivists, the paradoxes mentioned above about two clocks both going slower than the other and two measuring rods both shorter than the other are not real problems, but merely theoretical problems. Theoretical propositions that could not be spelled out in terms of observations were dismissed as "metaphysical," as if theories were mere instruments for making predictions. That attitude could be taken about the aforementioned paradoxes, because there is never any occasion in which two clocks can be directly observed both going slower than the other (or two measuring rods observed both shorter than the other). Observations are made from one inertial reference frame or another, and if both members of some pair of inertial frames are observed from a third reference frame, their clocks and measuring rods do not appear this way because of the Lorentz distortions that are introduced by its own velocity relative to them.

Though when taken as a description of material objects, the special theory of relativity is incompatible with the existence of absolute space, Einstein did not attempt to use its implications to show that absolute space does not exist. He was making a mathematical argument to show that accepted theories in Newtonian physics, which did assume the existence of absolute space, could all be replaced by theories that do not mention absolute rest or motion at all.xxii All he explicitly claimed was that physics does not require an “absolutely stationary space” and that the notion of a “‘luminiferous ether’ will prove to be superfluous” because the “phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the ideas of absolute rest” (Einstein, 1923 p. 37). It could be argued, therefore, that Einstein was merely imitating empiricist skepticism about theoretical entities generally by casting doubt on the reality of absolute space.

As it turned out, Einstein's theory proved to be remarkably successful in making surprising predictions of new experiments. For example, unstable particles have longer half-lives when moving at velocities approaching that of light. Clocks flown around the earth are indeed slowed down compared to clocks that stayed at home. The most famous new prediction of special relativity, E = mc2, has been confirmed repeatedly. It is a consequence of the relativistic increase in mass, which Einstein first pointed out, and without it, high energy physics as we know it today would be inconceivable. Finally, the equations of special relativity have become (after Dirac) the foundation of quantum field theory as well as Einstein’s theory of gravitation. The Lorentz transformation is now so basic to physics that “covariance” (or “Lorentz covariance”) is taken as a constraint on all possible laws of physics.

To be sure, Newtonian physicists complained about the loss of intuitive understanding that came with the acceptance of Einstein's way of explaining these phenomena. It was no longer possible to construct in ordinary spatial imagination a picture of the nature of the world. But that objection did not detract from the predictive success of Einstein's theory, and the Einsteinian revolution made the capacity of mathematical arguments to make surprising predictions of precise measurements the establishment criterion for accepting theories in contemporary physics.

But physics is not just mathematics. A theory in physics is generally thought to be true when it corresponds to what exists, and if the special theory of relativity does not correspond to material objects in absolute space, we want to know what it does correspond to. The success in making surprising predictions of what happens by which Einstein's theory has been confirmed means that it corresponds to regularities that hold of change in the world, but it is natural to want to know the nature of what exists that makes those regularities true. The answer given by contemporary physics is spacetime, and it was Minkowski that has made that answer possible.

Minkowski. In 1908, Minkowski offered a mathematically elegant way of representing what is true from all inertial frames, according to Einstein’s special theory of relativity, using only the coordinates of any single inertial frame.xxiii His was a “graphic method” which he said allows us to “visualize” what is going on. The key to his diagram was to represent time in the same way as space, and that is what has led to the belief that what exists is not space and time, but rather spacetime.

In Minkowski’s “spacetime diagrams”, time is represented as a fourth dimension perpendicular to the three dimensions of space (though when comparing two inertial frames, the spatial dimensions can be reduced to one by a suitable orientation of their coordinate frames). A material object at rest in space is represented, therefore, as a line running parallel to the time axis, and a material object with a constant, non-zero velocity is represented by a line inclined slightly in the direction of motion. Units for measuring time and space are usually chosen so that the path of light in spacetime (the “light-line”, t = x/c) bisects the time and space axes, making the “basic unit” of distance how far light travels in a unit of time.

Since the second frame of reference is based on a moving object, we can think of the tilted line representing its pathway as its time axis. From such a moving reference frame, the location of an object at rest in the first frame (such as one always located at its origin) would change relative to the moving frame. So far, this diagram of space and time would be acceptable in classical Newtonian physics, because it represents a so-called Galilean transformation for the coordinates of moving reference frames (in which distances in space would be related as x' = x – VT, where v is their relative velocity in the x-direction.)

What Minkowski discovered was that the Lorentz transformation for moving reference frames could be represented by tilting the space line of the moving frame equally in the opposite direction and lengthening the units of time and space. That is, the time-line and the space-line of the moving frame are inclined symmetrically around the pathway of light. (See the comparison of the Newtonian Diagram of Space and Time and Minkowski's Spacetime Diagra

In either the Newtonian or Minkowski's diagram, every point represents the location of a possible event in space and time (called a “world-point”), and superimposing a second reference frame makes it possible to give such coordinates in either reference frame. From the coordinates for any event in the first reference frame, we can simply read off the coordinates for the same event in the moving reference frame, and vice versa. In the case of event E, for example, the coordinates in the first frame are (2,1), and in Minkowski's diagram, they are (1.3,0.3). All possible reference frames can be represented in this way, each with a different tilt to its time-axis representing its velocity relative to the first.

The two reference frames in the Newtonian diagram have a very simple relationship, because time coordinates are the same for both reference frames and there is no change in the units of either time or space. But Minkowski's spacetime diagram represents the Lorentz transformation, and not only are the units of time and space different, but the space-line of the moving reference frame is inclined relative to the first reference frame.

Minkowski’s spacetime diagram yields the same coordinates for the second reference frame that are obtained from the Lorentz transformation equations deduced by Einstein. Thus, it predicts that measurements of the second inertial frame will reveal its clocks to be slowed down and its measuring rods to be contracted in the x-direction.

But since the Lorentz transformation works both ways, it is possible to start with the second (tilted) reference frame and obtain coordinates for events in the first reference frame. Thus, it predicts that the moving observers will detect Lorentz distortions occurring in the first frame. This symmetry about the relationship between inertial reference frames makes it impossible to single out any particular frame as being at absolute rest by comparing reference frames with one another.

Minkowski's spacetime diagram may seem to mitigate the paradoxes resulting from the symmetry of the relationship between members of any pair of inertial reference frames, because it enables us to "picture" two clocks both ticking away slower than the other and two measuring rods both shorter than the other. It is just a result of how the inertial reference frames are related to one another.

But this wonderful power of Minkowski's spacetime diagram to represent these puzzling phenomena would not be possible, if the space-lines of different reference frames had the same slope. The inclined orientation of the space-line of the second inertial frame relative to the first frame is crucial to representing the Lorentz transformation, and it represents a disagreement between inertial observers about simultaneity at a distance. That is, observers using different inertial reference frames will disagree about which events at a distance are simultaneous with the origins of their systems when they pass by one another. That is the source of all the ontological problems with the belief in spacetime.

Though it is possible to interpret Minkowski's spacetime diagram as just a useful mathematical device for predicting the measurements that would be made on different inertial frames, that is what the Lorentz transformation equations already do. The historical significance of Minkowski's diagram is that it enables us to "picture" what exists in a world where Einstein's special theory of relativity is the deepest truth about the world. Thus, it leads to the belief in spacetime (that is, "spatiotemporalism," as I called it in Spatiomaterialism, or "substantivalism about spacetime," as it is called in the literature.)

The belief in spacetime comes from realism about special relativity. Scientific realism holds that theories in physics are true in the sense of corresponding to what exists, and spacetime is what must exist, if Einstein's special theory of relativity is the deepest truth about the real nature of what exists as far as space and time are concerned.

With regard to space and time, Newtonian realists would say that what their theories correspond to is absolute space and absolute time, that is, to a three dimensional space all of whose parts exists at the present moment and endure simultaneously through time. But that is not what Einstein's special theory of relativity corresponds to, because it implies that observers on all possible inertial reference frames are equally correct about the times and places of the events that occur in the world, even though they disagree about the simultaneity of events at a distance. What all the different inertial observers say about the times and places of events can, however, be true at the same time, only if what exists is represented by Minkowski's spacetime diagram. Thus, spacetime is the natural answer to the question about what corresponds to Einstein's special theory of relativity. According to realists about special relativity, what exists is spacetime, a four-dimensional entity that contains time as a dimension and, thus, is not itself in time.

Though Einstein may merely have been arguing in the spirit of the empiricist skepticism that prevailed in philosophy at that time, Minkowski made it possible to give a realist interpretation of Einstein’s special theory. His spacetime diagram showed how Einstein's theory could be interpreted as a description of what really exists in the case of space and time. Minkowski must have realized that he was giving a realist interpretation of Einstein's special theory of relativity when he introduced his spacetime diagrams; he said (Minkowski 75) that “space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality”. In any case, later in the twentieth century, when logical positivism gave way to scientific realism, Einstein’s skepticism about absolute space, if that is what it was, spawned the belief in the existence of spacetime. Indeed, regardless what Einstein may have believed in 1905, he apparently came to agree that what he had discovered was spacetime. (See Einstein 1966, pp. 205-8).

Scientific realism is, however, a way of letting science determine one's ontology. That is not the best way to decide which ontological theory to accept, because the empirical method that science follows is to infer to the best efficient-cause explanation, and that may not be the best ontological-cause explanation. But we can see how realism led to an ontology based on spacetime.

Einstein's special theory of relativity was a better efficient-cause explanation of the relevant phenomena than Lorentz's way of defending his transformation equations, because it made all the same precise predictions of measurements, but in a mathematically simpler way. As an efficient-cause explanation, however, all that Einstein's special theory requires is an empirical equivalence of inertial reference frames. It assumes that inertial frames are experimentally indistinguishable from one another, and it derives a description about how they must appear to one another as parts of the same world (where Maxwell's laws of electromagnetism hold). That relationship is described by the Lorentz equations for transforming their coordinates into one another, and it is represented by Minkowski's spacetime diagram. But Einstein's was a mathematical argument, and no mechanism or cause of the empirical equivalence was given.

A realist interpretation of special relativity goes beyond mere empirical equivalence and holds that inertial frames are all ontologically equivalent. If special relativity is the literal and deepest truth about the world, then what observers on all possible inertial reference frames believe must be true at the same time. That is to hold, not merely that no experiment can distinguish any one inertial frame from all the others as the absolute frame, but that there is nothing about the nature of any inertial frame that makes it stand out from all the others. That means, among other things, that no assertion made by observers on one inertial frame can be true unless the same kind of assertion made by observers on every other inertial frame is also true. (Nor can any assertion made on one inertial frame be false unless the same kind of assertion made on every other inertial frame is also false.)

The virtue of Minkowski's spacetime diagram is that it enables us to "picture" what exists in a world where inertial reference frames are all ontologically equivalent. Though it may still be unclear what spacetime is, Minkowski's diagram does allow us to believe that all possible reference frames are related to what exists in the same way, for it accommodates all possible standards of simultaneity at a distance. But they can all correspond to what exists only if the world is a four-dimensional entity all of whose parts in both space and time exist in the same way.

It is clear that this ontological equivalence of inertial frames is incompatible with absolute space and time, because if space and time were absolute, one inertial frame would be singled out ontologically from all possible inertial frames. Only one of all possible inertial frames would have the correct standard of simultaneity. Its location in space and time could be shared by observers on many other inertial frames, but none of their claims about which distant events are simultaneous with their shared here and how would correspond to what exists.

Einsteinians do not use the term "ontological equivalence" to describe the relationship between different inertial reference frames, but that is what the belief in spacetime comes to. Most philosophers of space and time simply take it for granted that they must accept "substantivalism" about spacetime in order to interpret the special theory as a description of the real nature of what exists.xxiv

To believe in spacetime is to accept an ontology that is fundamentally different from Lorentz's Newtonian view, and the difference can be seen in what each implies about the nature of material objects.

Newtonian physicists assumed that material objects are substances that endure through time. They had to believe in absolute time, because the endurance theory of substances presupposes that only the present exists, or "presentism." (If the world is everything that exists, then objects that exist at only one moment in their histories must exist at the same time, for otherwise they would not be parts of the same world.) And since Newtonian physicists believed that material objects are all related to one another by (consistent) spatial relations, they were also forced to believe in absolute space. In a natural world, absolute time entails absolute space. Hence, the Newtonian world was made up of material objects in three dimensional space that endured through time.

Spacetime, on the other hand, is a four-dimensional entity. What exists is spacetime and all the events that are located in spacetime. Since time is an aspect of its essential structure, a spacetime world cannot endure through time. Thus, spacetime points and spacetime events must all exist in the same way independently of one another, if they exist at all. There are no material objects in a spacetime world, at least, not in the way that Lorentz believed. There are only the spacetime events that seem to make up the histories of so-called material objects. Thus, what is ordinarily called a "material object" is just a continuous series of spacetime events in spacetime. Its real nature is represented accurately by a “world line” in a spacetime diagram, because each spacetime event making up the history of a "material object" has an existence that is distinct from all the others, just as one point on a line exists distinctly from every other point on the line.

In short, whereas a material object in a Newtonian world exists only at each moment as it is present, but is identical across time, a so-called material object in a spacetime world is a continuous series of spacetime events, each of which exists eternally as a distinct part of the world. This is the difference between the endurance and perdurance theory of substances, and between the presentist and eternalist theory about time and existence.

Scientific realists sometimes assume that they can believe that Einstein's special theory of relativity corresponds to what exists without denying that they are themselves substances that endure through time by holding that only objects at a distance from themselves must exist the same way at all different moments in their histories. But that is not possible, if they believe that the truth of Einstein's special theory means that it corresponds to what exists for every observer. If Einstein's theory is universally true, then it must be true for inertial observers located elsewhere in the universe, and the only way that different inertial observes at a distance from us can all be correct about which moment in our local history is simultaneous with their passing by one another is if the moments in our local history all exist in the same way. We must perdure, rather than endure, because we are material objects at a distance for inertial observers elsewhere in the universe.

What Minkowski's “union” of space and time means ontologically is, therefore, that presentism is false. The denial of presentism is such a serious obstacle to an ontological explanation of the world that, in Spatiomaterialism, we were led to reject spacetime substantivalism (or "spatiotemporalism"), promising to justify it later by showing how it is possible for space and time to be absolute, despite the Einsteinian revolution. That is the argument we take up in the next section. But first, let us consider briefly why physics has ignored the ontological problems with eternalism.

What explains the ascendancy of the belief in spacetime is, once again, the empirical method of science and the physicists' addiction to mathematics as a means of practicing it. Behind Minkowski's spacetime diagram lies an elegant equation that has proved to be irresistibly attractive.

Minkowski provided a method of constructing in our own spacetime coordinate frame the spacetime coordinate frame that would be used by observers on an object moving relative to us. We may call their world-line the “moving timeline” (t = x/v), because it will be the time axis that moving observers use for their spacetime coordinate frame.

Minkowski formulated the conclusion of Einstein’s special theory as an equation that describes a hyperboloid in four dimensional spacetime: 12  = c2t2 - x2 - y2 - z2. (When we orient our x-axis in the direction of the others’ motion, we can ignore the other two dimensions and it reduces to 12 = c2t2 - x2.) (It is the red curve in the diagram depicting how Minkowski's spacetime diagram is constructed.) The intersection of Minkowski’s hyperboloid curve with our time-axis is the unit of time in our frame (t = 1), and the unit of distance (in “basic units”) is the distance in our frame that light travels during that period of time (x = 1). The moving timeline (the time-axis of the moving spacetime frame) also intersects the curve described by Minkowski’s equation, and the distance of that point along our time-axis is the length of a unit of time on the moving coordinate frame according to our clocks.

As the diagram shows, moving clocks are slowed down in our frame. The other axis of the moving spacetime frame, the “moving space-line”, is also deduced from Minkowski’s equation. Moving space-lines all have the same slope as the tangent to Minkowski’s curve at the point of the moving timeline’s intersection with his curve. (Its slope is v/c2; the points on any line with this slope are simultaneous in the moving spacetime frame.) Finally, the unit of distance on the moving space-line is how far light travels in the moving frame during a unit of time on the moving frame.

Inertial frames are all equivalent on Minkowski’s theory, as on Einstein’s, since Minkowski’s equation determines precisely the same hyperbola in every moving inertial frame constructed this way in our own spacetime coordinate frame. That is, their hyperbolas all coincide. In particular, the same procedure on the moving coordinate frame, using the same equation (and taking the velocity to be -v along the x'-axis), produces the original coordinate frame. Or more abstractly, Minkowski’s equation can be generalized as a measure, s, of the separation between any two events that is the same in every inertial frame, despite variations in their coordinates for particular events: s2 = c2t2 - x2 - y2 - z2.

In Minkowski’s equation, the parallel between the representation of space and time is remarkable. Time would be just another spatial dimension, except that it lacks a minus sign (and needs the velocity of light, c, to make units of time commensurable with distance). Indeed, that is how Minkowski includes relativistic mass increase. His equations’s form can be used to state the laws of nature that hold true in every inertial frame. In “four vector physics”, or “covariant” formulations of laws of physics, the energy of an object, E, takes the place of time and the three dimensions of momentum, p, take the place of the three spatial dimensions, so that the objects’ rest mass, m₀, rather than the separation, is what is the same about the object in all inertial frames: mo2c4 = E2 - px2c2 - py2c2 - pz2c2. The mathematics of four vector physics is so elegant and suggestive about the relationship of energy and momentum that it is not surprising that physicists now find themselves committed to the belief in spacetime.

By comparison with Lorentz’s ad hoc attempts to patch up classical physics in the wake of the Michelson-Morley experiment, Einstein’s argument was astonishingly simple and elegant, making it seem that Einstein had a deeper insight into these phenomena. And since Minkowski provided a diagram that made it possible to represent what special relativity implies about the world independently of particular reference frames, it is hardly surprising that the belief in spacetime has become the orthodox ontology in physics and the philosophy of science.

The acceptance of Einstein’s special theory of relativity involved, however, a remarkable change in the empirical method of physics, for it involved the abandonment of the requirement that explanations in physics be intuitively intelligible.

To follow the empirical method is to infer to the best efficient-cause explanation. Even in classical physics, theories were highly mathematical and confirmation was most convincing when they predicted surprising, quantitatively precise measurements. But since classical physicists still believed in absolute space and time, they also expected the best scientific theories to be intuitively intelligible, in the sense that it was possible to think coherently about what was happening in spatial imagination. But intuitive intelligibility was no longer possible when the best scientific theory required giving up the belief in absolute space and time. That was undeniably a loss, but physicists felt that they had to grow up and recognize that their deepest commitment was to judging the best theory by which is the simplest and most complete prediction of measurements. Since this came from mathematical theories, abandoning the requirement that physical explanations be intuitively intelligible left them addicted to mathematics.

What forced us to promise to explain how Einstein's special and general theories of relativity could be true in a world where space and time are absolute was the commitment of contemporary physics to the belief in spacetime. We had to take out that "mortgage" on spatiomaterialism as the foundation for ontological philosophy, because spatiomaterialism is committed to absolute space and time. This section will pay it off by showing how how the special theory of relativity can be true in a spatiomaterial world.

Let us recall, first, our reason for believing that space and time are absolute. We were inferring to the best ontological explanation of the world. That is not the method of empirical science, because an ontological theory is a theory about the nature of what exists, not only about what happens to it. The first basic issue about the nature of what exists has to do with the nature of time, and we concluded that we had to prefer presentism to eternalism because it alone could explain our observations about how the present moment is different from the past and future. Presentism holds that only the present exists. The past and the future do not exist. To be is to be in time.

We know by reflecting on ourselves as agents that the future does not exist, because if it did, we would not be able to control what happens in the world. We act as we do in order to make the future different from what it would be otherwise, and that would simply not be possible, if the future already existed. Every event must aleady be determined, if eternalism is true,

Reflection should be considered relevant evidence about the nature of what exists in the world, since the beings who do the reflecting are clear;y parts of that world. But contemporary physicists cannot escape this empirical falisfication of the belief in spacetime. There is also plenty of evidence for those who insist that only peception can supply the empirical data for choosing among theories. It is found in our perception of change. To perceive change, for example, to see a book falling from a shelf, is the recognize that certain spatial relations are going out of existence and other spatial relations are comming into existence. Defined as properties coming into existence and going out of existence, change might be called "presentist change," in order to distinguish it from "eternalist change," or change defined merely as objects having different properties or relations at different times. Anyone who perceives presentist change has plenty of observational evidence that only the present exists because properties (and spatial relations) cannot go out of existence, if the past still exists. Nor can properties (or spatial relations) come into existence, if the future already exists.

If eternalism were true, the present would not be different from the past or the future in this basic way, and thus, eternalism cannot explain what we observe about the nature of existence in perceiving persentist change.

Presentism is an indispensible assumption for any ontology that hopes to be explanatory, for it allows one to hold that what exists are substances that endure through time and, thereby, to explain what is found in the world as being constituted by basic substances and the manner in which they exist together as a world. All truths about the world, including truths about the past and the future, are thereby reducible to facts about what exists now.

On the other hand, if eternalism were true, one would have to postulate many more basic entities in order to explain the world, because one would have to postulate distinct basic entities for every moment in the history of every material object found in the world. Though such basic entities would not be substances in our sense, they would serve as the basic ontological causes in an eternalist explanation of the world, because they would constitute substances in our sense. The spacetime events that make up the world-lines of ordinary objects in Minkowski spacetime diagrams would be basic entities in this sense.

Eternalism is what makes the belief in spacetime unacceptable to empirically minded thinkers who want to know the truth about the nature of what exists. Empirical ontology seeks to discover the theory that corresponds to the basic nature of what exists, and since we have observational evidence that existence is what makes present different from the past and the future, any ontological theory that denies that fact is not very likely to be true. Indeed, it is empirically falsified by our perception of presentist change and our reflection on ourselves as agents.

Though “change” may be defined in terms of the difference between events located earlier and those located later on a world line, that is not presentist change (since there is nothing coming into existence or going out of existence over time). It is eternalist change. Presentist change entials eternalist change (since propositions about the future and the past can be reduced to propositions about the substances that exist now), but eternalist change does not entail presentist change (since there is no way to distinguish the present from the past and the future). Thus, there are observational facts that a presentist ontology, like spatiomaterialism, can explan that cannot be explained by any eternalist ontology, such as the belief in spacetime.

It is not the case that this problem about the nature of time has gone entirely unnoticed in the literature. Putnam [1967] noticed that substantivalism about spacetime contradicts our ordinary assumption about time (that only the present exists). But he focused on the incompatibility between the future being already determined and our view of ourselves as agents. Since he does not recognize reflection as observational evidence about the nature of what exists, he simply accepts the belief in spaceime as another case of scientific discoveries correcting ordinary beliefs. Putnam's point was also made by Rietdijk [1966].

Worries about having to hold that we are suffering a massive delusion in believing that the present is radically different from all the other moments in time are expressed by John Post (1987, Chapter 3) and Roger Penrose (1989, pp. 442ff). But it does not lead them to doubt that spacetime corresponds to the real nature of what exists.

Maxwell [1985], pp. 23-43, stands out as the only philosopher who sees the incompatibility of substantivalism about spacetime with our observation of how the present is different from the past and the future as justifying our rejection of the belief in spacetime in favor of the belief in absolute time. His view has not gathered support in the literature.

Others, like Stein [1968, 1991], have tried to avoid having to choose between the belief in spacetime and the openness of the future by taking the truth of Einstein's special theory of relativity to be relative to the “here and now.” He uses the velocity-of-light limit on causal influences between distant events to distinguish between spacetime events with a time-like relationship to the here and now (with the past being those events that could affect us here and now and the future being those that we could affect) from spacetime events with as space-like relationship to the here and now (namely those spacetime events that we could not affect and that could not affect us without effects traveling faster than the velocity of light). That allows Stein to take spacetime events that are related in a space-like way to the here and now as neither determined nor undetermined, but “indeterminate.” However, if relativity to the here and now does abandon the requirement that theories in physics be true at the same time for observers located everywhere in the universe, it does give up ontology as a theory about the nature of the substances that constitute the existence of everything in the world, for there is no way to explain indeterminate spacetime events by taking spacetime events to be the basic entities that constitute the world (much less by taking substances enduring through time to constitute the world).

Similar objections hold for the attempt by Smith ([1993], p. 4) to solve these ontological issues by reducing existence to “being real to.” What exists cannot be relative to any particular subject without giving up naturalism and accepting an ontology that makes subjective minds basic and reduces objects in space to them in some way.

Mathematics also obscures this issue in the literature. A logical analysis of the difference between invariant and ontological temporal relations is offered by Rakic [1997], but he apparently does not recognize that in introducing the ontological relation R, he is, in effect, adding Newtonian absolute time to STR. He does not see the ontological significance of his mathematical arugment.

In the face of the prima facie difficulties with accepting the belief in spacetime, it is surprising that there has been so little interest in replacing Einstein's special theory of relativity with an explanation based on the belief in absolute space and time. And it is all the more surprising, because the possibility of a “Newtonian” theory the phenomena covered by special relativity is widely admitted.

For example, it is admitted by Zaher [1989], Sklar [1992], and Dorato [1996], and it is even defended by Maxwell [1985], though for different reasons than will be given here. The equivalence of such a “Newtonian” theory to Einstein’s special theory is recognized by Maxwell [1985] and Smith [1993], shown mathematically by Prokhovnik [1985] and Bell [1987], and explained in a more intuitive way by Scribner [1989].

But commentators on Einstein’s special theory (such as Sklar 1992, pp. 27-30) often dismiss this possibility as a mere “compensatory theory”, as if it were a crutch for those who feel somehow psychologically crippled by the loss of an intuitively intelligible explanation, whereas our reason for believing in absolute space is that it is required by empirical ontology, given the observational evidence for presentism.

Spacetime is not, however, the only possible ontological explanation of the phenomenon described by Einstein's special theory of relativity. It is also possible to explain all those phenomena on the assumption that space and matter are substances enduring through time, even though that entails that space and time are absolute. We need only assume that space and matter are so related as basic substances constituting the world that the velocity of material objects through substantival space causes distortions in them in which clocks are slowed down, lengths are contracted in the direction of absolute motion, masses increase and forcefields are flattend in the direction of motion (all at the usual rate). These are the distortions that are implicit in the conclusions of Einstein’s argument, but in the following argument the order is reversed. Instead of assuming the principle of relativity and deriving the distortions as consequences, we shall assume the Lorentz distortions as basic laws of physics and derive the principle of relativity—that is, explain all aspects of the empirical equivalence of inertial reference frames by the Lorentz distortions.

There is probably an interesting story to be told about why Newtonian physicists did not defend such a theory about the empirical equivalence of inertial frames when it was still a live issue. Lorentz did explain the negative result of the Michelson-Morley experiment by the distortions he discovered, but he did even try to explain the symmetry in the transformation equations he used to describe them, because he thought of them as merely a convenient mathematical device for describing the effects of absolute motion on material objects. The reason that other physicists did not extend Lorentz's basically physical approach to explain why comparisons between inertial reference frames could not detect absolute rest and motion may be the devastating effects of World War I on the talent of that generation. An entire generation of potential physicists was wiped out, and after the war, the relative ease of reaching intersubjective agreement about mathematical arguments may have driven out the more divisive Newtonian arguments. To explain special relativity in terms of absolute space and absolute time requires intutive understanding, and such physical explanations could not be constructed without solving paradoxes about pairs of clocks both going slower than the other and light having the same velocity in different inertial frames. It also seemed ad hoc to postulate Lorentz distortions, since their only role in physics seemed to be making it impossible to detect absolute rest and motion. Einstein's elegant mathematical argument may have seemed superior in the young, abstract minds that picked up the discipline after the war untutored by the lost generation of Newtonian physicists. Thus, most students may simply have been taught Einsteinian equations from the beginning of their graduate careers, and those who demanded a more intuitive understanding of what they meant were weeded out as not being intellectually fit to do physics.

In giving the spatiomaterialist explanation of the truth of the special theory of relativity, I will start by following in the footsteps of Lorentz. But the spatiomaterialist explanation disagrees with Lorentz about what is required to explain special relativity, because it recognizes that it is necessary to explain not only the negative result of the Michelson-Morley experiment, but also why absolute motion and rest cannot be detected by comparing inertial frames with one another.

The inability to determine the absolute velocity of a material object by measuring the velocity of light relative to it is what Lorentz explained by postulating the slowing down of clocks and the shrinking of measuring rods in the measuring apparatus. Lorentz and Poincaré attempted to explain these distortions by the interaction of material objects with an ether, and I will suggest in the final section how they might be explained ontologically (by the unit-like, or quantum, electromagnetic interactions that constitute material objects in a spatiomaterial world like ours). In order to explain not only the kinematic phenomena on which Lorentz focused, but also the dynamic phenomena that make the laws of physics apply the same way on all inertial frames, it is necessary to recognize two additional distortions: an increase in mass and a flattening of forcefields in the direction of motion. But to focus on explaining the Lorentz distortions, even including all four, is to fail to recognize that there is another, quite puzzling aspect of the phenomena described by Einstein’s special theory that needs to be explained.

The puzzling aspect is the symmetry that holds between members of each pair of inertial frames. It is implied by the Lorentz transformation equations, and it is an essential part of the principle of relativity as the empirical equivalence of all inertial reference frames, for it implies that absolute rest and motion cannot be detected by comparting inertial frames with one another. Explaining this symmetry will require a two-step argument. The first step is to show that the effect of following Einstein’s definition of simultaneity at a distance in absolute space is to mis-synchronize clocks on a moving inertial frame in a certain way. The resulting disagreement about the simultaneity of events at a distance is widely recognized, but its role in causing the symmetry between inertial frames is not. Hence, the second step is to show how the mis-synchronization combines with the Lorentz distortions themselves to make it appear that the Lorentz distortions are always occurring symmetrically in the other inertial frame.xxv

The Lorentz Distortions. To hold that space is a substance enduring though time is to hold that space is absolute, and we have assumed that space is the medium of light transmission. There is an inherent motion in space that gives light a constant velocity relative to absolute space. On that basis, the spatiomaterialist theory must explain why inertial frames all appear to be alike, that is, why the velocity of light seems to be the same and why the laws of physics all apply the same way in every inertial frame. This "local equivalence" among inertial frames must be explained as a mere appearance, because motion across absolute space must change the velocity of light relative to the moving object, as suggested by the analogy to the boat moving through ripples in a pond. And the laws of physics describing interactions among material objects (dynamic phenomena) make different predictions for material objects with different velocities. In order for it to be impossible to detect absolute motion, moving material objects (that is, objects with with rest mass) must be distorted in certain ways.

There are four kinds of distortions in material objects with high absolute velocity: a slowing down of clocks, a contraction of lengths in the direction of motion, an increase in the mass of moving objects, and an decrease in the strength of forces in the direction of motion. These are what I will call the "Lorentz distortions." Only the first two were actually discovered by Lorentz, but all of them are required for the same kinds of reasons. Though I will not give a formal mathematical argument, enough will be said about each to explain their quantitative aspects.

The rate involved in all these distortions is , where v is absolute velocity. This is the rate of distortion that is required to explain why Michelson and Morley were unable to detect absolute motion by using an interferometer to measure the velocity of light. This apparatus reflects light from two mirrors lying in mutually perpendicular directions, and the velocity of light in each direction is determined by measuring the period required for each two-way trip (by the interference of the waves coming from the two directions).

Time dilation. Assume that one mirror lies forward in the direction of absolute motion with the other transverse to it. The need for physical interactions to slow down on moving objects can be seen by considering what happens on the transverse pathway as the apparatus moves through absolute space.

The transverse pathway of the interferometer is, in effect, a “light clock”, using the velocity of light to measure time. Since the velocity of light in absolute space is fixed, the light in a light clock with absolute motion must travel farther than in a light clock at rest, and that means that the moving light clock is slowed down. It is slowed down at the same rate that all physical processes must be slowed down in order to keep this effect from being detectable. (See diagram of the path of light on the transverse light clock.)

Light traveling along the transverse pathway must go farther than it would, were the apparatus at absolute rest, because to return to its starting place, the light must also keep up with the apparatus, which is also moving through space all the time that the light is traveling. To observers on the moving object, light seems to travel directly to the mirror and back, but its path in absolute space is actually along the hypotenuse (ct) of the triangle formed by the transverse pathway (L) and the motion of the starting point in absolute space (vt). This increases the period required for the two-way trip.

The period is increased at the usual rate (except as a function of absolute, rather than relative, velocity). The rate is obtained by Pythagoras’ theorem for the right triangle depicted in the diagram (L2 + v2t2 = c2t2) and solving for t. Since L/c is the period it would take light to travel to the mirror at absolute rest, the period required for each leg on the moving apparatus is .

Length contraction. The need for a contraction of the size of material objects in the direction of motion can be seen by considering what must happen to light clocks oriented in the direction of motion in order for absolute motion to be undetectable. Unless their lengths were also to shrink, it would still be possible to detect absolute motion by comparing the longitudinal light clock with the transverse light clock, because the former would be even slower than the later.

In addition to the distance back and forth along the longitudinal pathway, the light on the longitudinal must also cover, as we have seen, all the space that the apparatus itself travels during the period of its two-way trip. But in the longitudinal direction, there is a new factor at work, because the two legs of its trip are unequal. Light must travel farther in absolute space on the outward leg in the direction of the apparatus’ motion than on the return leg, because of the motion of the apparatus in absolute space.

That means that, relative to the apparatus, the effective velocity of light toward the (forward) mirror is slower than when coming back. On the outward leg, the velocity of light relative to the apparatus is c - v, and on the return leg it is c + v. But light spends more time traveling slower in the outward direction than it does traveling faster on the return leg, and since the effect on the total time of travel depends on how long it travels at each velocity, it does not make up all the time lost during the outward leg on the return leg. The whole period required would be longer than the period required on the transverse pathway, because with equal distances to cover to the forward mirror and back, it spends a longer time going at the slower (at c-v) than it spends going faster (at c+v). That would make absolute motion detectable, unless the measuring rod were contracted.

If material objects also shrink (at the usual rate), the measurements made by the interferometer will be the same regardless of its absolute motion and the principle of relativity will seem to be true. The required rate is easy to calculate because the new length, L', must be such that the period for the two way trip, L'/(c - v) + L'(c + v), is equal to the period for a two-way transverse trip derived in the foregoing discussion of time dilation. Simply solve for L'.

The two remaining distortions follow from the temporal and spatial (or “kinematic”) distortions, for unless there were further distortions, Newton’s laws of motion, notably his second law (F = ma), would be false and the deviation from what it requires would be a measure of absolute velocity. Time dilation and length contraction are both relevant to dynamic phenomena, because both are involved in the acceleration of material objects, which Newton’s law says is proportional to the force exerted on them. Thus, there are two dynamic distortions, an increase in mass and a decrease of the force field in the direction of motion, corresponding to the kinematic distortions.

Mass increase. The necessity of an increase in mass follows from the temporal distortion, because unless the masses of material objects increase at the usual rate with absolute motion, Newton’s second law of motion (F = ma) will be false and physical processes will not take place the same way in absolute motion as at rest.

For example, dynamic clocks, such as pendulum clocks and wind-up alarm clocks, which depend on the acceleration of material objects to measure time, would disagree with light clocks, and the difference between the two kinds of clocks would be a measure of absolute motion.

Consider a dynamic clock oriented in the transverse direction of the inertial frame’s absolute motion. Since light clocks are slowed down, the dynamic clock would seem to be speeded up, since the pendulum (or whatever) would be accelerating over the whole distance just as quickly as it does at rest. The only way the dynamic clock can be slowed down to match the slowing down of the light clock is for the mass being accelerated to be increased at the same rate the light clock is slowed down. Thus, mass must increase at the rate as a function of absolute velocity as time is slowed down.

Longitudinal decrease in the force field. The necessity of a decrease in forces exerted in the direction of motion follows from the spatial distortion, the shrinkage of measuring rods in the direction of motion, for unless the longitudinal force field decreases with absolute motion at the usual rate, Newton’s second law of motion will still be false and deviations from its predictions will be a measure of absolute motion.

Consider a dynamic clock oriented in the direction of the inertial frame’s motion. Although the mass of the pendulum (or whatever) will be increased at the usual rate and, thus, slowed down, it will still be accelerating under the force at the same rate for the same period as the transverse dynamic clock. But since measuring rods are contracted in the direction of motion, the pendulum would still seem to be accelerating faster, because it would seem to be going farther in the same length of time. In order for absolute motion to be undetectable, the pendulum in the longitudinal direction must accelerate more slowly over space. But it is not possible for this acceleration to be slowed down by a further increase in mass, since mass is a scalar quantity, which does not depend on the direction of motion, and only acceleration in the direction of motion has to be slowed down. The only way the acceleration of the pendulum could be slowed down only in the longitudinal direction is for the size of the force field in that direction to be decreased at the usual rate as a function of absolute velocity.xxvi

Thus, in order to explain the "local equivalence" of inertial frames, that is, why absolute velocity cannot be detected by measuring the velocity of light relative to the moving object and why dynamic clocks do not disagree with light clocks, as if their reference frames were at absolute rest in space, we need only assume that the nature of matter is such that these four distortions occur when material objects are in motion across absolute space. There are two kinematic distortions and two dynamic distortions, all at the same rate as a function of absolute velocity. The first two are the distortions first described by Lorentz, and the latter two are distortions that Einstein showed were entailed by the Lorentz transformation equations when mass and force are also taken into consideration.

In order to show that spatiomaterialism can explain the truth of Einstein’s special theory of relativity, therefore, I will assume that matter has this nature.

I have shown the necessity of these distortions here by following Lorentz and arguing backwards from the Michelson-Morley experiment to what is required for absolute velocity to be undetectable by measurements of the velocity of light on any given inertial frame (or from comparisons of dynamic clocks and light clocks), they are not as ad hoc as that makes them seem. As I will argue in the final section, they are the same distortions that would be caused by the nature of ordinary material objects, if they were constituted by unit-like electromagnetic interactions among its parts (among molecules, among atoms within molecules, and between protons and electrons within atoms).

What made it possible for Einstein to infer the Lorentz distortions from his principle of relativity (and his assumptions that light has the same velocity relative to every inertial frame) is that these are the only distortions in material objects that would make absolute velocity undetectable by measurements of the velocity of light and comparisons between light clocks and dynamic clocks. But since they are merely implicit in the Lorentz transformation equations he derived, they appear in the paradoxical form of symmetrical distortions between any pair of inertial frames, and that is the other aspect of these phenomena that needs to be explained.

The Symmetry of the Lorentz Distortions in Pairs of Inertial Frames.The four Lorentz distortions make it impossible to detect absolute rest (or absolute motion) by any local experiment, that is, by ordinary interactions among material objects on moving inertial frames, such as interferometers and comparing light clocks with dynamic clocks. But as Einstein's argument emphasized, the empirical equivalence of inertial frames implies that they are equivalent globally as well as locally. It is also impossible to detect absolute motion by experiments involving the relationships between inertial frames with high relative velocity, for example by comparing how fast their clocks are ticking or how long their measuring rods are. And as the symmetry of the two sets of Lorentz transformation equations implies, what makes it impossible to detect absolute motion by such global experiments is that the Lorentz distortions always appear to be occurring in the other inertial frame as a function of the velocity of the two references relative to one another. Thus, in order to explain the empirical equivalence of inertial frames ontologically, we must explain this symmetry in the members of any pair of inertial frames as an appearance.

The first step in that explanation is to take note of how clocks on inertial frames are mis-synchronized by using Einstein’s definition of simultaneity at a distance, if the velocity of light is actually due to an inherent motion in space itself.

The second step is to show how that mis-synchronization of clocks on inertial frames moving rapidly across space combines with the Lorentz distortions that they are actually suffering as a result of their absolute motion to make it appear that Lorentz distortions are always in the other inertial frame (and that the rate seems to be a function of their relative velocity).

The mis-synchronization of moving clocks. The strategy of spatiomaterialism is to explain the truth of the principle of relativity on the assumption that all forms of matter, including light and material objects, coincide with parts of space. The assumption that both matter and space are substances enduring through time makes it possible to explain presentist change, but it also entails that space and time are absolute. Thus, it must reject Einstein’s definition of simultaneity at a distance.

Einstein stipulates that a local event is simultaneous with the moment of reflection of a light signal from a distant mirror when that local event occurs halfway through the total period required for the signal to travel there and back. That is to assume that the velocity of light is the same in both directions. This assumption is true on inertial frames at absolute rest, but it is not true on objects moving through absolute space. If light everywhere has a fixed velocity relative to absolute space, the velocity of light relative to a moving frame is slower traveling outward in the direction of forward motion and faster in the opposite direction. Thus, clocks on moving frames that are synchronized according to Einstein’s definition of simultaneity at a distance will be actually mis-synchronized. It is important to be clear about the nature and amount of the error introduced, because mis-synchronization plays a crucial role in causing the appearances that make absolute motion undetectable by comparing inertial frames with one another, or the symmetry of Lorentz distortions in pairs of inertial frames.

The most revealing way to show the mis-synchronization is to use a diagram to represent the spatial and temporal relations among the relevant events. This is to use the Newtonian diagram of space and time, which is the spatiomaterialist counterpart to Minkowski’s “graphical method” of using spacetime diagrams for “visualizing” what is going on, and it is both simpler and easier to understand. Since spatiomaterialism assumes that space is a substance and, thus, absolute, the argument may begin with the coordinate frame at rest in absolute space. Nothing precludes representing time as an axis perpendicular to spatial dimensions, as long as we do not assume that anything exists but what is located on lines parallel to our absolute space-axis (horizontal lines in the diagram) for each moment. We can refer to events in the past and future, even though they do not exist, because they can be interpreted as references to space and matter which have, as substances, an existential aspect that entails that they did exist and will exist. We can also represent the motion of the other inertial frame as a timeline whose slope depends on its velocity (t = x/v), as Minkowski did. Furthermore, we can take this timeline to be the time-axis of the moving inertial frame, because that involves only a simple Galilean coordinate transformation of the kind used in Newtonian physics. So far, this is equivalent to Minkowski’s spacetime diagram.

Spatiomaterialism cannot, however, go on to assume that the moving frame has a space-axis that is inclined relative to our absolute space-axis, as Minkowski's spacetime diagram does. We must assume that moving measuring rods always lie parallel to the absolute space-axis, since all parts of moving rods are particular substances and must exist at the same time. But spatiomaterialism does hold, following Lorentz, that moving measuring rods lying in the direction of motion are contracted, and so we must recognize that the moving measuring rod is shorter than it would be if it were at absolute rest. Now, to see the significance of Einstein’s definition of simultaneity at a distance, we need only consider the geometry of synchronizing clocks in absolute space and time, that is, from the point of view of the absolute frame depicted below. (See the diagram below comparing the synchronization of both forward and afterward clocks on the absolute and moving inertial reference frames.)

The foregoing diagram depicts the general nature of the mis-synchronization, but we will need to know just how much clocks are mis-synchronized. Thus, consider the following diagram in which the moving measuring rod is depicted as L'.

The length of the contracted moving measuring rod in absolute space is L'. It is depicted at four locations that it occupies at crucial moments during the process of synchronization. The thinner inclined lines trace the path of each end of the rod where clocks are located. The thin dotted-line represents the path of the light used to synchronize the clocks at each end. Following Einstein’s definition of simultaneity, (1) moving observers send a light signal forward from the origin of their frame, (2) the light is reflected from a mirror at the forward end of their measuring rod (and the clock there is set at 0), and (3) they record when it returns. Einstein’s definition requires moving observers to set their clocks on the assumption that the light was reflected halfway through the total period required for its round trip. Since the light signal reaches the mirror in the period T₁ and returns to the observers in the period T₂, they assume it was reflected at (T₁ + T₂)/2 after the light was sent. Thus, they set their nearest clock so that it would have read 0 at that moment. But since the measuring rod is actually in absolute motion, the light does not reach the mirror at the far end until it has passed both the length of the measuring rod and whatever distance the rod travels during the first leg (T₁). And on the return leg (T₂), light does not have to travel the whole distance of the measuring rod, since the other end is also moving toward the light. But since moving observers assume that the reflection occurs halfway through the period required for the round trip, they are, in effect, assuming that the set of simultaneous events lies on the line that runs through the halfway point on the timeline for the clock at the observers’ end of the measuring rod and the point of reflection at the mirror on the timeline for the clock at the forward end of the measuring rod. That is what moving observers take to be their space-line as seen by us from the frame at absolute rest.

The result of mis-synchronizing clocks is precisely the same diagram for the moving frame that Minkowski constructed from his hyperboloid curve, representing the conclusion of Einstein’s special theory. (The same results would also follow from the Lorentz transformation equations.) However, we have derived the moving observers’ apparent space-axis (or space-line), not from a mysterious equation, but in a perfectly intelligible way. The moving space-line is rotated upward in the diagram, because the moving clocks have been mis-synchronized. And they have been mis-synchronized because the moving observers have followed Einstein’s definition of simultaneity at a distance, which assumes that the velocity of light is the same both ways in every direction relative to any inertial frame.

The amount of the error introduced by mis-synchronization will be as important as its cause in the next step of this argument, so bear with me for one final point. The home clock reading 0 is one event in absolute space and time, and the forward clock reading 0 is another event. The separation between them in the absolute frame has a curious value, both in space and in time. The moving measuring rod has a length of L', but the distance in absolute space between these two events turns out to be L'/(1 - v2/c2), which means that the mis-synchronization makes it seem that the moving measuring rod is expanded at the square of the usual rate (see above diagram). The length of time between the two events can be derived from the slope of the moving space-line in the diagram for absolute space and time (that is, v/c2).xxvii This is the slope of the tangent to Minkowski’s mysterious curve at the point of intersection with the timeline for the observers’ nearest clock,xxviii and it occurs in the second expression in the numerator for the Lorentz transformation for time.xxix But in this context, the slope means that the difference in time between the events is v/c2[L'/(1 - v2/c2)] (or the product of the slope of the moving space-line and the distance between the points on it in absolute space). We will use these values shortly.

The Cause of the Apparent symmetry of Lorentz distortions. Attempt to detect absolute motion by measuring the rate of clocks and the length of measuring rods on the other inertial frame are "global experiments," and the reason that absolute motion cannot be detected is that the Lorentz distortions appear to be symmetrical. Since transformation equations must work both ways between any two inertial reference frames, this symmetry is entailed by Einstein's argument for the Lorentz transformation equations in his special theory of relativity. And this symmetry is an essential part of the empirical equivalence of inertial frames that Poincaré called the "principle of relativity."

If the clocks and measuring rods were material objects in absolute space, this symmetry would imply that clocks on two inertial frames passing one another in space are both going slower than the other and that their longitudinally-oriented measuring rods are both shorter than one another. It is one of the reasons that Einsteinians must give up the belief in absolute space and time. By the same token, spatiomaterialism must explain this symmetry about pairs of inertial frames as a mere appearance of space and matter as substances enduring through time, just as the local equivalence was.

This is the part of the explanation of the empirical equivalence of inertial frames that Lorentz left out of his Newtonian theory. But it is readily supplied by the geometry of events in absolute space and time. The apparent symmetry of the distortions is a result of the actual Lorentz distortions suffered by the moving frame, together with the mis-synchronization of moving clocks, as we can see by considering how the measurements of the others’ clocks and rods are made.

Length contraction. Consider first the apparent symmetry of length contraction. The most direct way to measure the others’ standard of length is to make simultaneous marks from both ends of one’s own measuring rod onto the other inertial frame as it passes by and compare that distance with the others’ measuring rod. This works fine for absolute observers; they mark off a distance longer than moving measuring rods lying in the direction of motion, indicating that the moving measuring rods are contracted. But it also seems to moving observers that absolute rods are contracted in the direction of motion, and we can see why by considering what takes place in making the measurement.

It is because (1) clocks on the moving frame have been mis-synchronized and (2) moving measuring rods are contracted. We have just seen that moving observers mis-synchronize their clocks when they accept Einstein’s definition of simultaneity: the distance in absolute space between the events at which moving clocks at both end of a moving measuring rod read the same time is equal to an expansion of the actually contracted measuring rod at the square of the usual rate, that is, (1 - v2/c2). Thus, when moving observers make what they think are simultaneous marks on the absolute measuring rod that is passing by, they mark off a distance on the absolute frame that is longer than their actually contracted measuring rod by the square of the usual rate, and since that distance is longer than the absolute measuring rod by the usual rate, the absolute measuring rod seems to be contracted at the usual rate.xxx

In other words, as the absolute inertial frame comes toward them, the mis-synchronization of their clocks leads moving observers to make a mark from the afterward end of their own measuring rod first and then, after the moving frame has traveled some distance, they make a second mark from the forward end, so that distance marked off on the absolute frame includes both the length of the contracted moving measuring rod and all the distance that the absolute frame travels between making the two marks. That virtual expansion of the moving measuring rod makes it appear that the absolute measuring rod is contracted.xxxi

The error introduced by mis-synchronization is, in short, a virtual distortion at the square of the usual rate, but in the opposite direction, so that when the method of measuring combines it with the actual shrinkage of the moving measuring rod, the effect is to make absolute measuring rods seem distorted at the usual rate relative to the moving rod. This same “geometrical mechanism” is at work in the measurement of how fast the other’s clocks are ticking.

Time dilation. The most direct way for us to measure the speed of clocks on the other inertial frame is for us to move in our inertial frame along with one of the others’ clocks that is passing by and to compare it with the series of clocks on our own frame by which we will be passing. (Observers cannot take a clock with them as they move through their own frame, because that would make it a clock on the other frame. But nothing precludes observers from keeping up with the other inertial frame and using clocks already located at various points on their frame for the comparison.) When observers on the frame at absolute rest keep up with the moving clock and compare it with a series of their absolute clocks, they observe the real slowing down of the others’ clock caused by its absolute motion. The symmetry of the distortions means, however, that when observers on a frame in absolute motion keep up with an absolute clock and compare it with the series of their own moving clocks by which they pass, the absolute clock seems to be slowed down.

But in the latter case, it is because (1) clocks on the moving frame have been mis-synchronized, (2) the moving observers are moving backwards on their own moving frame (-v) to keep up with the absolute clock, and (3) clocks on the moving frame are slowed down. The amount of deviation of a distant moving clock from absolute simultaneity with a local moving clock is, as we saw, a function of the distance in absolute space between the events at which two moving clocks have the same readings, namely, v/c2 times the absolute distance (the slope of the rotated space line). In this measurement, that distance depends on how long the moving observer has been traveling at -v, that is, the distance -vt'. Thus, the deviation of the next clock from absolute simultaneity will be VT times v/c2, or -t'(v2/c2). That amount of time plus the time that elapses during the moving observers trip from one clock to the next (that is, t') yields a total apparent time period of t' - t'(v2/c2), or t'(1 - v2/c2), which is a virtual speeding up of moving clocks at the square of the usual rate of distortions. Thus, since (1), the mis-synchronization of moving clocks, combines with (2), the moving observers’ motion on the moving frame, to produce, in effect, a virtual speeding up of moving clocks at the square of the usual rate, the result, when combined with (3), the actual slowing down of moving clocks at the usual rate, is that the absolute clock being compared with them appears slowed down at the usual rate.xxxii,xxxiii

In sum, given how the measurements are made, the mis-synchronization of moving clocks introduces a virtual distortion through which the moving observers’ own distortions are projected onto the absolute inertial frame. This can be seen in our diagram of events happening to particular substances in absolute space and time, for as we found, the mis-synchronization shows up as a rotation of the moving space-line that involves both a virtual speeding up of moving clocks and a virtual lengthening of moving measuring rods. Thus, to see how it gives rise to the apparent symmetry of the distortions, consider how the measurement of the others’ clock is represented below.

When absolute observers keep up with the moving clock and compare it with a series of their own clocks, they follow the moving timeline. When the moving clock says t'=1, they compare it with an absolute clock (located on that absolute space-line) which reads t=1/(represented by the horizontal line labeled I in the diagram). And when moving observers travel backwards on their own frame to keep up with the absolute clock, they follow the absolute timeline (x=0). When they pass by their own moving clock reading t'=1, they compare it with the absolute clock which reads t= (represented by the rotated moving space-line labeled II in the diagram). The difference between these two measurements is obviously due to the rotation of the moving space-line, which, as we have seen, comes from mis-synchronizing moving clocks. Notice that the absolute clock’s reading of t=1 lies between these two comparisons. Therein lies the power of mis-synchronization to cause the appearance. Combining the slope induced in the moving space-line by mis-synchronization (v/c2) with the movement of the moving observers in making the measurement (x' = VT, that is, keeping up with the absolute clock) is equivalent to a temporal distortion on the moving frame at the square of the rate of the actual distortion (1-v2/c2), but in the opposite direction. So, it combines with the actual slowing down of moving clocks to make the absolute clock seem slowed down relative to moving clocks.

The diagram also shows how the mis-synchronization is responsible for the apparent symmetry of the contraction of measuring rods. But in this case, it is the virtual expansion of the moving measuring rods induced at the square of the usual rate by the mis-synchronization that is relevant. When absolute observers make simultaneous marks on the moving frame, they find that the moving measuring rod is contracted at the usual rate (labeled III in the diagram). But when moving observers make what they think are simultaneous marks on the absolute frame, they actually mark off a distance that is expanded at the square of the usual rate (labeled IV in the diagram). Once again, the power of mis-synchronization can be seen in how the actual moving measuring rod is contracted relative to the absolute measuring rod and the virtual moving measuring rod is expanded relative to the absolute rod, both at the usual rate.

The symmetry of Lorentz distortions is, therefore, a symmetry betwen real distortions in reference frames in absolute motion and apparent distortions in the reference frame at absolute rest, and it is a thoroughgoing symmetry, which holds for all the basic ways of measuring the other frame's clocks and measuring rods. Indeed, any of the standard measurements can made from either member of the pair of inertial frames, though when they are considered from the point of view of the other inertial observer, they reveal that the other's clocks are speeded up and the other's measuring rods are expanded in the direction of motion. This can be seen in the table of measurements.

This explanation of the apparent symmetry of the kinematic distortions also accounts for the apparent symmetry of the dynamic distortions (though the longitudinal distortion in the force field is not always recognized as such by Einsteinians), for the apparent increase in absolute masses is implied by the false belief that absolute clocks are slowed down and the assumption that Newton’s laws apply the same way on all inertial frames (Einstein’s principle of relativity). Likewise, the apparent decrease in longitudinal forces is implied by Einstein’s principle of relativity and the false belief that absolute measuring rods are contracted in the direction of motion.

The apparent symmetry of the four distortions has been explained for the special case in which one of the inertial frames is at absolute rest, but it can be generalized to explain the apparent symmetry between any two objects moving in absolute space. In the general case, the rate of the apparent distortions is a function of their (apparent) relative velocity, and what is detected on both sides is partly a result of real distortions and partly illusions caused in the way described above.xxxiv

Though observers on any pair of inertial frames agree about their relative velocity, it is worth noting that, on the spatiomaterialist explanation of the empirical equivalence, their measurements of relative velocity do not coincide with their real velocity relative to one another in absolute space: the apparent relative velocity is never more than the velocity of light, but the real velocity of inertial frames relative to one another can approach twice the velocity of light, because light moves at that velocity in opposite directions from any given point in absolute space.

Conclusions. One part of the promise made in Spatiomaterialism in order to use this ontology as a foundation for demonstrating necessary truths has been kept. We have seen that spatiomaterialism can explain the truth of Einstein’s special theory of relativity, and means that nothing established empirically by Einstein’s theory forces us to give up spatiomaterialism. Thus, if spatiomaterialism can also explain the truth of Einstein’s general theory of relativity (and quantum mechanics), physics will provide no grounds for doubting that spatiomaterialism is the best ontological explanation of the world. But there are a few implications of this ontological explanation of special relativity that should be noted in conclusion.

First, though we have discovered the power of absolute velocity to cause changes in material objects by following in the footsteps of Lorentz, that does not mean that we must postulate an ether in addition to absolute space.

Lorentz and Poincaré both expected to explain time dilation and length contraction as the result of an interaction between material objects and an ether at rest in absolute space (as if material objects were made of nothing but electrons that interact with the electromagnetic ether as they move through it). Though material objects must also have something to interact with on our explanation of the Lorentz distortions, we can take it to be space itself. We have postulated space as a substance that contains matter, and having already used that relationship to explain the truth of the laws of classical physics, we now use it to explain the Lorentz distortions. Indeed, I have suggested reasons for expecting Lorentz distortions to occur apart from what is necessary to make absolute motion undetectable.

Though there is no luminiferous ether, there is still a medium of light propagation, and it still makes sense to hold that there is an inertial frame in which light has the same one-way velocities in every pair of opposite directions. That will be important in our explanation of the truth of Einstein's general theory of relativity, because we will not always assume that the light medium is at absolute rest in space. The aspect of space by which it serves as the medium of light propagation is more complex than it appears now, because we shall have to assume that the velocity of light varies with location in space in a way that can be seen as depending on the velocity of the light medium relative to space. It is as if the ether were being accelerated in space, but even though that may suggest that the light medium is an ether after all, we will still not postulate an ethereal substance coinciding with space to explain this phenomenon.

Second, the difference between the actual Lorentz distortions in material objects with absolute velocity and the apparent symmetry of Lorentz distortions in pairs of inertial frames revealed by this ontological explanation shows that the mathematical representation of special relativity is hiding an aspect of reality.

The mathematical way of saying that inertial frames are all equivalent is to say that the laws of physics are covariant, or Lorentz covariant. That means that laws of physics that apply in one frame take the same form in any other inertial frame, that is, when they are subjected to the Lorentz transformation. (This equivalence is what is represented by Minkowski’s equation for the absolute separation between any two events and is the foundation for the equations of four-vector physics, which do not mention any specific inertial frame.) Einstein’s original article showed that covariance holds in the case of electromagnetism, and imposing covariance as a requirement on other physical theories has generated predictions that turn out to be true.

Despite the obvious simplicity, comprehensiveness, elegance, and fruitfulness of this mathematical representation of special relativity, however, it is a mistake to take covariance to be the deepest and most complete truth about the real nature of the world. Our ontological explanation of the truth of special relativity reveals that covariance actually represents two different phenomena, with two different ontological causes. There is the local equivalence of inertial frames, which is caused by the actual Lorentz distortions, and there is the global equivalence, which is caused by the mis-synchronization of clocks and how that makes one’s own Lorentz distortions appear to be in the other inertial frame.

Third, this ontological interpretation of the mathematical representations used in special relativity confirms that the method of physics is implicitly skeptical about ontological causes that are not entailed by realism about its efficient cause explanations.

When physics infers to the best efficient-cause explanation, it looks for laws of nature that represent the quantitative aspects of the regularities involved, because such mathematical representations can often be used to predict surprising, precise measurements that confirm their truth. The empirical method of science is so dependent on mathematical representations that, once experiments have confirmed their predictions, physicists are realists about their efficient-cause explanations. They let scientific realism determine their ontology.

Accordingly, the belief in spacetime is simply realism about special relativity. That is, substantivalism about spacetime is the ontology that results from taking the simplest mathematical theory that can predict all the relevant phenomena to correspond to what exists. Since the special relativity holds that all inertial frames are empirically equivalent, scientific realism takes the empirical equivalence among inertial frames to be an ontological equivalence. That is to replace absolute space and time with spacetime. But it is also the leave out an aspect of reality, for it is to ignore the observable fact that only the present exists.

Finally, the principle of relativity itself turns out to be merely a practical principle, without ontological significance. Though as a practical matter, the assignment of coordinates to events can be made only relative to an inertial frame whose absolute motion cannot be known, that does not mean that they do not have actual locations in absolute space as time passes. There is an absolute truth about the dates and places of events. Even though we can never know what they are, we can know that there is a fact of the matter about when and where they occur. That is what is implied by this ontological reduction of special relativity. I have called it an explanation of empirical equivalence, because by explaining the apparent truth of the principle of relativity, it denies that this relativity is a basic principle of physics.xxxv

The Ontological Causes of the Lorentz Distortions. Lorentz explained the negative result of the Michelson-Morley experiment by distortions in material objects caused by their motion through absolute space, and his own research focused on explaining those distortions as an interaction between material objects and the luminiferous ether according to his electron theory of matter, a theory that is now known to be false. He could have simply assumed the Lorentz distortions as basic laws of physics, as we have thus far, but we will travel once again in Lorentz's footsteps by considering a deeper explanation of his distortions, an ontological theory that makes use of our assumption that there is an inherent motion in space and which uses certain assumptions about the nature of material objects that will not be defended until we explain the truth of quantum mechanics ontologically.

By contrast to Einstein's elegant mathematical derivation of the Lorentz transformation equations from the assumption that inertial frames are all empirically equivalent, Lorentz's Newtonian theory seemed merely to be tinkering with classical physics in an ad hoc manner. First, he recognized the length contraction, and then a few years later, a time dilation. And to extend his argument to explain why dynamic phenomena do not reveal absolute rest or motion, two more distortions would need to be recognized (an increase in mass and a flattening of force fields).

The Lorentz distortions are, however, neither arbitrary nor contrived. In fact, there is a certain necessity about them, as I will try to demonstrate by showing how they follow from what is known about the nature of material objects (or rather from the spatiomaterialist ontological explanation of what is known about them) together with our assumption that space is the medium of light transmission (with the velocity of light manifesting an inherent motion in space).

It is now known that material objects are constituted by electromagnetic interactions among its constituent parts, and the assumption that is required in order to explain the truth of quantum mechanics ontologically is that those electromagnetic interactions have a unit-like nature (or a “quantum” nature, as it is called).

Atoms, for example, are made of a nucleus of protons and neutrons which interacts by electric and magnetic forces with a number of electrons that is normally equal to the number of protons. It is a stable configuration, because the nature of those electromagnetic interactions between the nucleus and the electrons is such that the potential energy cannot be lower (that is, no more of their rest masses can be converted to kinetic energy or other forms of matter). That is contrary to what is expected according to the laws of classical physics. They imply that electrons would quickly spiral into the nucleus, radiating all their energy away as electromagnetic waves. But that does not happen, and the attempt to explain why not led to the discovery of quantum mechanics. The structure of the atom was one of the first discoveries.

On the ontological explanation of quantum mechanics defended in Quantum Mechanics, there is a unit-like, or quantum, nature to electromagnetic interactions. Interactions cannot take place unless they involve a certain minimum quantity of action. Thus, the energy level of electrons bound to a nucleus in an atom can change only in a step-like way, each involving a whole quantum of action in which the energy is carried away by a photon, the units of which electromagnetic waves are composed , according to quantum mechanics. And there is a minimum energy level for electrons in atoms, because in that state, as we shall assume, such electrons are bound to the nucleus by the smallest electromagnetic interaction possible.

The details about the unit-like nature of these quantum electromagnetic interactions will be discussed later. (See Change: Quantum mechanics.) What is relevant here is that material objects generally are constituted by such unit-like electromagnetic interactions among simpler material objects with electric charges. Not only atoms, but also molecules, crystals, and other complex structures composed of atoms depend on electromagnetic bonds among electrically charged parts that exhibit this quantum nature.

Material objects are composed of many such quantum electromagnetic interactions. They give the material object its structure as a whole, because all these quantum events not only coincide with space in a consistent geometrical pattern, but also fit together in time. Any given material object can interact with more than one other material object at a time, and since the quantum interactions are synchronized, the effects of different interactions of the object can be repeated regularly in the same way, cycle after cycle, constituting a structure that does not change over time.

We are assuming that space is the medium of light transmission, and since light is constituted electric and magnetic forces coupled according to Maxwell's laws, space must also mediate the exertion of such forces. Our working hypothesis is that space has an inherent motion by which it mediates light transmission, and thus, if electric and magnetic forces are exerted across space as time passed by way of an inherent motion in space, the electromagnetic interactions involved in the constitution of material objects will inevitably be affected by the object's motion through space as a whole. And the way that they are affected, given this ontological explanation of their quantum nature, explains the Lorentz distortions.

Whatever is going on in the quantum interactions constituting material objects, it involves the exertion of electric and magnetic forces, and any such inter-action requires photons traveling both ways between them. But since we have assumed that the motion of photons depends on the inherent motion in space, the material object as a whole will inevitably be affected by its motion across space, because it will change the effective velocity at which those forces are exerted.

I will assume that in each unit-like electromagnetic interaction, say, between the nucleus of an atom and one of its electrons, a photon travels, first, one way between the objects and, then, back the other way between them before a single quantum interaction is completed. (Indeed, the interaction may involve symmetrical two-way trips of photons, one starting from both of the objects involved in the interaction.) Such two-way trips are necessary, because quantum interactions occur only as a whole, if they occur at all. Never is one of the objects changed while the other is not. Since the objects are separated from one another in space, the only way that one of the objects can change when, and only when, the other object also changes is by something traveling both ways across space between them in the period of time that it take to complete the unit-like action. Nothing less is ontologically possible, if there are such unit-like electromagnetic interactions.

The material object’s motion across space will not make much difference as long as its velocity is small compared to the velocity of light. In fact, the velocity of light (that is, the inherent motion in space) is so enormous that the effect on most ordinary material objects is undetectable. Nevertheless, since material objects subject to appropriate forces will continue to accelerate, they can acquire velocities approaching that of light, and the objects will be affected by the change in the one-way velocities of light. There are four effects, and I will describe them qualitatively here, since an ontological explanation is meant to identify the aspects of the substances to which physical laws correspond. Their quantitative aspects would clearly be the same as the Lorentz distortions.

Slowing down of quantum interactions. The first and most obvious effect of high absolute velocity in space is a slowing down of all the quantum electromagnetic interactions constituting the material object, so that all processes take place more slowly.

Slowing down is inevitable, because in each unit-like interaction, the photons being exchanged must travel not only the distance between the parts with electric changes, but also all the distance covered by the material object as a whole in the time it take to complete the unit-like interaction.

Suppose, for example, that one of the electromagnetic interactions constituting an atom is oriented perpendicularly to the direction of the atom's motion through space. In order to complete the interaction, a photon must travel from the nucleus to the electron and then back again in the period of a single unit of interaction. But all the time that the photon is traveling, the atom as a whole is also moving across space, and thus, in keeping up with the atom, the photon will have to travel farther that in it would at rest. Since its velocity is due to the inherent motion in space, the photon cannot speed up, and so it will take longer to complete the two-way trip between the nucleus and electron. Unit-like electromagnetic interactions will take longer to complete on a moving atom than they would at rest. And since this is true of all the unit-like electromagnetic interactions constituting material objects, all physical processes involved will be slowed down at the same rate as a function of their absolute motion. (The quantitative description of this effect of absolute velocity is given in the discussion of the Lorentz Distortions.)

Longitudinal shrinking of quantum interactions. A less obvious, but no less necessary, effect of high velocity motion across space is a shrinking of the size of quantum electromagnetic interactions in the direction of absolute motion.

The two-way trip of an electromagnetic interaction in the direction of motion will be slowed down just as much as such a unit like interaction in the direction transverse to motion described above, because once again, the photon will have to cover all the extra distance across space that the material object as a whole covers during the period required to go both ways. Thus, the longitudinal quantum interactions will be synchronized with the transverse quantum interactions. But a further distortion of the quantum interaction is required in the direction of motion, because in order to remain synchronized with the transverse quantum interaction, the photon must travel a shorter distance.

The additional effect comes from the asymmetry of the two-way trip of the photon in the longitudinal quantum interaction constituting a material object, such as an atom. Unlike the transverse quantum event, the motion of the material object as a whole makes the effective velocity of light different in each direction. When the photon is traveling from the nucleus to the electron in the same direction across space as the atom itself, it has a lower velocity relative to the atom than it would at rest, because the other object is moving away from it all the time it travels. And then, on the return leg of its two-way trip, the photon is traveling in the opposite direction, and that makes its velocity relative to the atom higher, because its destination is moving toward it. The problem is that, even though the distance between the nucleus and the electron is the same both ways, the velocity of the photon is different, and thus, it cannot complete the two way trip in time to be synchronized with transverse quantum events -- unless the distance is shortened. The effect on the total time of travel depends on how long the photon spends traveling at each velocity, and since it spends more time traveling slower than the velocity of light relative to the atom on the forward leg than it does traveling the same distance faster than the velocity of light on the return leg, its completion of the two way trip would be delayed -- unless the distance between the electron and the nucleus were less than it would be at absolute rest.

This effect can also be seen from the point of view of absolute space. The photon traveling in the direction of motion has farther to go to reach its destination than in the opposite direction, because in the forward direction, its destination is moving away from it and in the backward direction its destination is moving toward it. Though the effects of the two legs are in opposite directions, they do not cancel out, because the photon spends more time chasing destinations that are retreating than it does traveling toward destinations that are approaching it. It cannot make up on the return leg all the time it loses on the forward leg. (The quantitative description of this effect of absolute velocity is given in the Lorentz Distortions.)

The first two distortions in material objects with a high velocity are what must happen, if material objects are constituted by synchronized, unit-like electromagnetic interactions and the propagation of electric and magnetic forces is due to an inherent motion in space. But two further changes in material objects are required in order for them to interact in the ways described by the basic laws of physics, one affecting the masses of the objects involved and the other affecting the forces they exert. They too can be explained ontologically, given the the various forms of matter that we have already postulated in order to explain the laws of classical physics.

Increase in mass. Quantum electromagnetic interactions involve the exertion of forces, as if the objects involved were accelerating one another in some way, and in order for forces to have the same effects on material objects with high velocity as they do on material objects at absolute rest, a further change is necessary, because the same interaction takes longer to be completed when the material object is moving across space at a high velocity.

Consider a quantum interaction in the transverse direction constituting a material object, such as an atom. The transverse distance between the two objects is not changed, but the time required for the interaction to take place is longer. The only way that it is possible for an unchanged force to accelerate an object more slowly is when the mass of the object is greater. Newton’s second law holds that the force is equal to the mass times the acceleration, and since the acceleration is lower, the mass must be greater by at the same rate.

Thus, we assume that the increase in the period of the unit-like electromagnetic interactions is accompanied by a similar increase in the masses of the objects from what their masses are at rest. And since all the quantum interactions among all the parts of the material object in motion are slowed down, the (rest) masses of all the parts increase accordingly, and thus, the (rest) mass of the material object as a whole increases at the same rate.

The increase in the mass of the moving material object can be explained, on our ontological explanation of the basic laws of classical physics, as simply the kinetic energy it acquires by its motion. Kinetic energy is one of the forms of matter, and since the quantity of matter determines its mass, the kinetic matter required to have a high velocity in absolute space can explain the increase in its mass.

The quantitative aspects of this explanation depends on the theory of kinetic matter in Change: Quantum mechanics. But we can already see, in principle, how its mass could increase to infinity as the material object approaches the velocity of light. In order to increase the velocity of the material object, each bit of kinetic matter as well as each bit of rest mass must be accelerated, that is, given additional kinetic matter, and thus, the amount of kinetic matter required to increase it at higher velocities depends on how much kinetic matter it already has. The limit is the velocity of light because of how the units of kinetic matter involve the velocity of light.

Longitudinal decrease in electric field. Though all quantum interactions suffer a time dilation and increase in mass, quantum interactions in the direction of motion suffer an additional distortion, which shrinks the lengths of the material objects they constitute. What remains to be noticed here is that such a shrinkage in the length of the moving material object also involves a change in the shape of the electric force fields exerted by charged objects. Instead of being spherical, they are flattened out in the direction of motion.

The electric force field is, we are assuming, a form of electromagnetic matter that is spread out around the center of mass of the object with a electric charge. It is what is responsible for the electric force that the nucleus, say, exerts on its electrons. But as we have seen, the forces exerted by way of such an electric field can act only over a shorter distance, and that requires us to hold that the electric field itself is shorter in the direction of motion than it is in the transverse direction.

Though the electric field is a form of matter according to this ontological explanation, it is not just matter being dragged along by the center of mass with the charge. The electric field is shortened both in front of the electric charge and behind by the same amount (with the transverse distance unchanged). Since that shortening is the result of having to complete a two-way trip with different one-way velocities of light, that suggests that the matter making up the electric field itself must be explained as a cyclic, unit-like change when we take up the ontological explanation of the basic particles (the simplest bits of matter with rest mass).

Let us assume, therefore, that the essential nature of matter making up a spatiomaterial world like ours is such that material objects in motion suffer these four kinds of changes, or “distortions” from what they are like at absolute rest, as a result of motion through a substantival space in which an inherent motion is responsible for the exertion of electric and magnetic forces.

Let me emphasize that the foregoing explanation of the four distortions is intended only to show how the four Lorentz distortions in moving material objects are not mere ad hoc contrivances for patching up a hole in Newtonian physics, but fit comfortably into this ontological explanation of the truth of physics, including its explanation of quantum mechanics.

Such an explanation of the four distortions is not required, however, to meet the challenge of showing that it is possible for spatiomaterialism to explain the truth of Einstein’s special theory of relativity. It would be enough simply to assume the Lorentz distortions as part of the basic nature of matter, as if they were basic laws of physics. Hence, doubts about the ontological assumptions I have made about the nature of material objects to explain the Lorentz distortions should not cast doubt on the capacity of spatiomaterialism, in general, to explain the truth of Einstein’s special theory of relativity.

Einstein’s general theory of relativity.By showing that spatiomaterialism can explain the truth of Einstein’s special theory of relativity (STR), I have answered the first part of the Einsteinian reservation about using spatiomaterialism as the foundation for demonstrating ontologically necessary truths. In this section, I will answer the second part. Einstein’s general theory of relativity (GTR) also makes it appear that this is not a spatiomaterial world, and I will show how its truth can also be explained by spatiomaterialism.

The way Einstein’s general theory of relativity explains gravitation does not, at first, seem compatible with spatiomaterialism. The foundation of the general theory is spacetime, for gravitation is explained as a “curvature” in spacetime, and since substantivalism about spacetime is incompatible with substantivalism about space, it seems out of the question that what the general theory refers to as “curved spacetime” could turn out to be an aspect of space and matter as substances enduring through time. (For a very accessible account of Einstein's general theory of relativity, see Clifford M. Will's Was Einstein Right?)

It is, however, possible for spatiomaterialism to explain why Einstein’s general theory of relativity is true. The key is what spacetime turns out to be in the ontological explanation of the truth of the special theory of relativity, for that makes it possible to explain curved spacetime as well. Curved spacetime is also an aspect of space and matter, even though as substances that endure through time, space and matter exist only at the present moment.

Though I go on in the next section to suggest an ontological explanation of quantum mechanics and, in the following section, take up some basic issues in cosmology, this explanation of the Einstein’s general theory of relativity pays off the second mortgage that we took out in order to use spatiomaterialism as the foundation for our philosophical argument. (See Necessary Truths.) Quantum mechanics is not so crucial to this project, because there is continuing disagreement about its ontological implications and some of the possibilities are compatible with spatiomaterialism.

We have already seen how the existence of consciousness can be explained in a spatiomaterial world (though the unity of consciousness will not be explained until I take up the mammalian brain in the sixth stage of evolution), and I have yet to take up the nature of goodness and holiness. But one of those four mortgages will be repaid when we see that Einsteinian physics provides not reason for denying that this is a spatiomaterial world.

In fact, spatiomaterialism might welcome the challenge of explaining Einstein’s general theory of relativity, because that means it does not have to defend Newton’s theory of gravitation. Newton’s theory is prima facie less hospitable to spatiomaterialism than general relativity. If a force did act immediately at a distance, it would contradict the principle of local action, implying that spatiomaterialism is false.

Newton’s theory describes an attractive force by which every material object acts immediately on every other material object, including those at a distance. Newton introduced it, in effect, as the best efficient-cause explanation of Kepler’s laws of planetary orbits, and it was confirmed by the deduction of many surprising, quantitatively precise predictions of measurements, becoming the model for the empirical method in physics. Despite its predictive success, Newton’s law of gravitation had nothing to say about how such forces are exerted on objects at a distance, except that they act instantaneously at a distance.

Action at a distance was puzzling to classical physicists, since it did not fit well with their intuitive understanding of nature as composed of space and matter in time. Even Newton was uncomfortable with the notion, and he refused to make any hypotheses about how gravitation worked in his Principia.xxxvi But action at a distance could not be rejected for being incompatible with spatiomaterialism, for that would require using space as an ontological cause, and Newtonian physics did not recognize the validity of ontological arguments. Still, when Einstein proposed an explanation of gravitation that implied that gravitational forces propagate at a finite velocity, even physicists were relieved at not having to believe in action at a distance. And it did remove what would otherwise be an insuperable objection to spatiomaterialism.

Einstein’s general theory of relativity was, however, another highly mathematical hypothesis, which predicted many quantitatively precise measurements, and since it implies that gravitational acceleration is caused by a curvature of spacetime, a realist interpretation of Einstein’s theory seems to imply that spacetime is a substance. But if the real nature of what exists in addition to mass and energy is spacetime, that is, a four-dimensional entity in which time is one of the dimensions along with space, then existence is not in time and “real change” is not ontologically possible. Thus, general relativity solved one ontological problem, but only by introducing another. The challenge is, therefore, to explain how curved spacetime can be understood as an aspect of a world constituted by space and matter as substances that exist only at the present moment.

Curved spacetime.Having discovered STR by assuming the local equivalence of all inertial frames, Einstein sought to use the same approach in explaining acceleration due to gravity, that is, by including reference frames that were being accelerated by gravitation. Thus, the main assumption of his general theory of relativity is the equivalence of inertial frames to reference frames falling freely in gravitational fields.

What Einstein himself called the “principle of equivalence” assumes that nothing can be detected within any reference frame (that is, locally) that would distinguish a reference frame in inertial motion from one in free fall.

Or, to put Einstein’s equivalence principle the opposite way, a reference frame at rest in a gravitational field is indistinguishable from one being accelerated by a force; the push that we ordinarily call the “force” of gravity is actually the force of the earth accelerating us upward from what is equivalent to inertial motion.

This further equivalence can be only local, however, because free-falling frames are obviously different in how they are related to the rest of the world, or globally. Though inertial frames simply continue in motion indefinitely, free-falling reference frames eventually collide with the center of gravity, because gravitational fields are imposed by matter concentrated at certain locations. Thus, what makes the general theory of relativity general is that it includes both inertial and free-falling reference frames, and Einstein’s highly mathematical description of how they fit together as parts of a single world is a theory of acceleration due to gravity.

Einstein’s strategy in GTR paralleled that of his special theory. In STR, Einstein used his principle of relativity (implying the equivalence of all inertial frames) to derive a mathematical description of how they must be related globally (the Lorentz transformation equations). In his general theory, Einstein started with the assumption that reference frames in free fall are locally equivalent to inertial frames, and using the four-dimensional, spacetime mathematics from special relativity, he derived equations describing how all reference frames, inertial and free-falling frames, are related to one another. In both theories, the equivalence of reference frames means that the laws of physics hold the same way on each of them. That means that there is a mathematical transformation of explanations of events given on any one reference frame into explanations given on the other in which the laws of physics have the same form. In special relativity, only a Lorentz transformation was required, making them Lorentz covariant. But in general relativity, it is a more general transformation, which includes both inertial frames and free-fall frames, called “general covariance”. How objects change their motion depends on centers of mass in their neighborhoods, and using general covariance as a constraint, Einstein was able to deduce equations that describe what classical physics attributed to a force of gravity.

Einstein’s general theory of relativity describes a spacetime world in which the accumulation of matter (both mass and energy) causes a “curvature” in the surrounding spacetime. This curvature explains the acceleration that Newtonian physics attributed to a force of gravitation, because it determines, in turn, the inertial path for any matter located there. (Such an inertial path though curved spacetime is called a “geodesic”).

GTR also predicts various new phenomena, including the bending (and slowing down) of light rays passing through gravitational fields, the precession of the perihelion of Mercury, and a gravitational red shift. These predictions all differ from classical physics, and since GTR entails the possibility of black holes, including rotating black holes, it has become the foundation of cosmology. Except for the precession of Mercury’s perihelion, these phenomena were not even expected before Einstein’s argument, much less explained, and so the confirmation of these predictions justified accepting the general theory by the empirical method of physics.

Realism about the general theory of relativity, like realism about the special theory, makes it hard to avoid thinking of spacetime as a substance on a par with what it contains. The curvature of spacetime is supposed to cause the acceleration of mater that is ordinarily attributed to gravity, and it would be hard to explain how a property of spacetime can have such an effect on what it contains, if spacetime did not exist independently of matter.

GTR is, like STR, a highly mathematical theory. Gravitation is described by the Einstein field equations, which relate the distribution of mass and non-gravitational energy to the curvature of spacetime. Currently, GTR is usually interpreted in terms of differential geometry. Spacetime is postulated as a four-dimensional continuous manifold of points (M), and there are two kinds of (tensor) equations defined everywhere on the manifold. The metric-field tensor (g) defines the metric (and geometric) relations among points in spacetime, and the stress-energy tensor (T) represents the distribution of matter (mass and energy) in spacetime (and its effects).

Jointly, M, g, and T are called a “model” of GTR, and even for a world with a particular distribution of mass and energy, there are infinitely many different, yet empirically equivalent models. They all predict the same gravitational phenomena, but each model involves a different coordinate system, for each is based on a different local inertial reference frames at its location in spacetime, that is, adapted to material objects with different free-fall trajectories.xxxvii Their empirical equivalence is an assumption that Einstein used to derive his field equations, and it is one of the meanings sometimes given to “general relativity”. On this geometrical approach, GTR also seems to imply substantivalism about spacetime, because the four-dimensional manifold of points (M) must be postulated in order to define the metric-field tensor (g) and stress-energy tensor (T).xxxviii

The challenge that GTR poses for spatiomaterialism is that it implies that what exists is spacetime, rather than space and matter existing as substances in time. In a spacetime ontology, time is another dimension of what exists on a par with the spatial dimensions (except for a change in sign and the velocity of light as a scaling factor). Its implications about time were used in Spatiomaterialism: Time to show that spatiomaterialism is a better ontological explanation of nature than spacetime ontology (or “spatiotemporalism”). Substantivalism about spacetime makes it impossible to explain “real change”, because if what exists is a four-dimensional entity, and time is part of its structure, then nothing can be coming into existence or going out of existence as time passes.

As we saw in Spatiomaterialism, there is no way for spacetime substantivalism to avoid refutation by the fact that our experience of change itself take place through time and we are parts of nature, except by postulating an additional, subjective substance, for whom spacetime and the events it contains have the appearance of real change. Not only does the addition of such a subjective substance make spacetime ontology more complex, but it also poses the problem of relating eternal and enduring substances as parts of the same world, a problem that Plato never solved. And even if it could be solved, this modification would be ad hoc, for it would explain nothing but the appearance that change takes place through time. There is, therefore, no question that spatiomaterialism is a better ontology, if it is possible.

In order to show that spatiomaterialism is possible is to show that it can explain why GTR appears to be true, and that means explaining all the relevant phenomena on the assumption that nothing exists but space and matter enduring through time. This is to describe a model or solution of the Einstein field equations that differs from the prevailing geometrical interpretation because, instead of postulating a four-dimensional manifold and defining geometrical objects on it, spatiomaterialism postulates space and matter as substances enduring through time. Nothing exists in a spatiomaterial world but what exists at present, and thus, the interaction of space and matter must somehow have an aspect that explains what Einsteinians are referring to when they talk about “curved spacetime” and that aspect must explain all the phenomena predicted by the general theory.

We can tell that not in principle impossible for a world of substances that exist only at the present moment to explain the truth of GTR, because even on the received geometrical interpretation, there is a standard of simultaneity implicit in each model’s assignment of space and time coordinates to every event in the universe. All the spacetime events with the same temporal coordinates that we now have in some model for our universe (a certain “simultaneity hypersurface” in curved spacetime) could be all that actually exists at the present moment, and their spatial coordinates could be referring to parts of a three dimensional Euclidean substance. Of course, this could be true of only one model, for although every model assigns some coordinates to us now, different models entail different standards of simultaneity, and if different models were ontologically equivalent, the substances constituting the world would have to include spacetime.

Moreover, in order to hold, in effect, that one of all possible models represents absolute space and time, spatiomaterialism would have to show that there is a law of gravitation that explains not only the approximate truth of the Newtonian theory in it, but also all the new phenomena predicted by GTR. We can also tell that such a law is not in principle impossible, because GTR itself implies that the relevant events in that model are all related in a regular way. Still, the regularity would have to be described without referring to spacetime or spacetime curvature, that is, explained as constituted by (Euclidean) space and matter enduring through time. And there would be problem about the regularity, only if its description turned out to be very complex.

Finally, since spatiomaterialism would take reality to be equivalent to what exists in a single model of GTR according to the received geometrical approach, we should also expect the spatiomaterialist law of gravitation to explain why different models are observationally equivalent, that is, to explain “general relativity”, in the sense that enabled Einstein to derive his mathematical representation of gravitation.

This is a tall order, but it is possible, as I will show here by giving an ontological explanation of why Einstein’s GTR is true. It is an intuitively intelligible explanation, rather than a mathematical explanation, because what is required to explain the truth of any theory ontologically is showing that there are aspects of the substances postulated by the ontology that correspond to the theory. That requires a qualitative argument, which identifies the kinds of regularities and how they are related according to the theory, and then shows that they can all correspond to aspects of the same world. To be sure, the aspects of the substances pointed out must be quantitatively adequate as well. But that is rather trivial, once the qualitative argument has shown what the parameters are, how they are related to one another, and the signs and order of magnitude of their quantities, because substances can be postulated as having whatever quantitative aspects are required to make the measurements come out correctly. Thus, I will leave it as a challenge to those who would disprove spatiomaterialism to show that the aspects identified here cannot all be quantitatively accurate.

Acceleration of the inherent motion in space.How can gravitation be explained in a spatiomaterial world? To be adequate, it must explain not only the acceleration due to gravity that Newton recognized, but also all the new phenomena predicted by the general theory of relativity. That is a challenge, because it must do so without appealing to spacetime. How can gravitation be explained with nothing but two opposite substances that exist only at the present moment?

As in the reduction of special relativity, there is no need to reject the mathematical equations or the interpretations by which they are tested empirically. All that needs to change is what we take them to refer to. Since we shall be starting from the assumption that space is absolute, this is to take an approach opposite to Einstein, just as we did in explaining special relativity.

Einstein called his explanation of gravitation a general “theory of relativity” because he assumed that gravitational phenomena, like all other phenomena, must obey the same laws in every reference frame, and his strategy was to explain gravitation by describing a way of transforming coordinates assigned by observers on different reference frames into one another that leaves the laws of physics unchanged. He assumed that the velocity of light has the same value in every reference frame, and a tensor calculus was required to formulate the mathematical transformation.

As ontologists, however, we start by assuming that space and matter are substances existing in time, and since that means that light may have different (one-way) velocities, different reference frames are not ontologically equivalent. Thus, it is not appropriate to call it a theory of relativity. On the contrary, it will explain the general equivalence of reference frames, or the premise of Einstein’s argument, as an appearance constituted by space and matter as ontological causes, much as it did in explaining the premises of Einstein’s argument in STR.

The key to the spatiomaterialist theory of gravitation is its explanation of the apparent truth of STR.

In its ontological explanation of the truth of the special theory, spatiomaterialism rejects Einstein’s assumption that the velocity of light is the same relative to every inertial frame and assumes, instead, that it is due to an inherent motion in space. It also assumes (or shows) that the motion of material objects through space causes four Lorentz distortions in them. The Lorentz distortions enable it to explain why inertial frames are empirically equivalent locally, and by taking into account how clocks are mis-synchronized on moving reference frames by adhering to Einstein’s definition of simultaneity at a distance (that is, ignoring the difference between the one-way velocities of light in each direction), they also explain why inertial frames appear to be equivalent globally, that is, why the (net) Lorentz distortion always seem to be occurring in the other member of any pair of inertial frames.

These assumptions and conclusions are all taken for granted in explaining the truth of the general theory of relativity, and only one additional ontological assumption is required to explain gravitation. That is the assumption that the accumulation of matter at certain locations in space has an effect on space, mediated by the inherent motion in space, that, in effect, accelerates the inherent motion in the nearby space toward it.

There are various consequences of this assumption. They are described in the following sections, including their role in explaining the new phenomena predicted by Einstein. One consequence has to do with the velocity of light. Another has to do with effect on material objects that are forced to remain at rest relative to space itself in a gravitational field. The third is a result of how the effect of matter accumulation on space is mediated by the inherent motion itself. Finally, I will show how it explains the special phenomena that occur in very strong gravitational fields, such as black holes. At the end, I will return to the issue about the nature of the argument and show how this ontological explanation of gravitation explains “general relativity” in the sense of the observational equivalence of different models of GTR, which Einstein used to derive his conclusions.

In constructing its theory of gravitation, spatiomaterialism takes its lead, as Einstein did, from the assumption that reference frames free-falling in gravitational fields are equivalent (locally) to reference frames in inertial motion. Einstein called this the “principle of equivalence.” But given its explanation of the truth of STR, this principle has a somewhat different meaning, for spatiomaterialism holds that different inertial frames, despite being observationally equivalent, are ontologically different.

When inertial frames have different velocities relative to one another, at least one must be moving relative to space, and since that means having a velocity relative to the inherent motion in space, we had to assume that material objects suffer Lorentz distortions as a result of their motion relative to the inherent motion in space, in order explain why they appear equivalent (locally and globally). Now, in order to explain all the old and new gravitational phenomena, we must assume yet another interaction between space and matter — an interaction that makes it appear that free falling frames are observationally equivalent, locally, to inertial frames outside gravitational fields.

Whereas Einstein took gravitation to involve an interaction between matter and spacetime, spatiomaterialism takes gravitation to involve an interaction between matter and space. Spatiomaterialism assumes that, instead of curving spacetime, accumulations of matter (mass and energy) change the velocity of the inherent motion in space.

I am speaking as if the inherent motion were something actually moving though space while space endures, as a substance, through time, but I have admitted that, if you prefer, it can be taken as just a spatio-temporal aspect of substantival space having to do with how fast what occurs in one location in space can affect what happens elsewhere. If space is to mediate the relations and interactions among bits of matter, some such limit on the velocity of their effects on one another is necessary, because otherwise spatiomaterialism would have to give up its assumption that space is a substance made up of many particular substances (one for each location in space and all connected as described by Euclidean geometry). There is no doubt that space involves an “inherent motion” in the sense of having a spatio-temporal aspect about how parts of space are related.

The only issue is whether there is anything actually moving through space other than bits of matter. That can be doubted, because, thus far, at least, the only candidates for what moves across space are bits of matter. Setting material objects aside (because the move slower than the inherent motion), we have, thus far, come across nothing that actually moves across space at that maximum velocity except light (and the forces exerted by material objects with an electric charge), which are forms of matter. The gravitational force is not an exception, for even though it also propagates at the velocity of the inherent motion, it is also a form of matter even on this theory (as I suggested in Forms of matter). But it does no harm to think of this aspect of the nature of space as an inherent motion, for we have already recognized that space is a substance enduring through time and seen that it must have a spatio-temporal aspect to the relations of its parts. Moreover, in explaining how quantum mechanics can be true in a spatiomaterial world, we will find that something other than matter also moves across space with the inherent motion.

Thus, I will continue to speak of space as if there were an inherent motion through every location, moving at the same velocity both ways in every direction in three dimensional space. It is something we can imagine, because as rational beings, we are able to think about space, time and motion, and thus, it will enable me to describe the effect of matter accumulation on space in a qualitative way, in terms of its effect on the inherent motion and, thereby, on all the electromagnetic interactions that are mediated by it.

Those with a more reactionary bent may, however, want to call the inherent motion in space by its traditional name. It is actually an ontological explanation of the ether. The luminiferous ether was supposed to be a material substance of some kind at rest in absolute space that mediated electric and magnetic forces like a very elastic material substance. To be sure, we have no need to postulate any form of matter to play the role of the ether, because we take space to be a substance, and its inherent motion can mediate electromagnetic interactions. But on the other hand, it would be appropriate to speak of the inherent motion in space as the ether, and that means that the new assumption being made here could be described just as well as an acceleration of the ether. (I would use this term, except that it is likely to inflame the antagonism of Einsteinians, who sometimes like to portray their denial of absolute space as merely discrediting a foolish metaphysical belief in unobservable entities.)

The assumption that spatiomaterialism makes in order to explain gravitation, therefore, is that the accumulation of matter exerts a force on other nearby bits of matter by way of its effect on the inherent motion in space that changes the velocity of the inherent motion in space as if the inherent motion itself were being accelerated toward the center of gravity at the rate described by Newton’s law.

The inherent motion flows both ways in every direction, and the gravitational change in the velocity of the inherent motion is different in opposite directions. The inbound velocity of the inherent motion is greater than it would be outside the gravitational field, and the outbound velocity is correspondingly less than it would be outside. Thus, it is as if the inherent motion itself had an inbound velocity.

Since the inherent motion is a velocity both ways in every direction at every location in space, there is always some pathway for material objects relative to it in which the two one-way velocities of inherent motion are equal in both directions. Let us call that motion relative to space “rest relative to the inherent motion” (or for reactionaries, “rest relative to the ether”). The effect of the force of gravity is, therefore, equivalent to accelerating rest relative to the inherent motion in space, so that it has velocity relative to space in a gravitational field.

(It might, therefore, be better to describe the effect of the force of gravity as accelerating the ether, because it is rest relative to the ether that is undetectable. But that could be misleading. It might suggest that ethereal matter is accumulating at the center of gravity, whereas the inherent motion is just the way in which bits of matter coincide with space, and thus, the acceleration of the inherent motion is just a change in how bits of matter coincide with space. But it is useful to keep in mind that there is an inertial frame at rest relative to the inherent motion, and it is, in effect, what is accelerated by the accumulation of matter.)

The inbound velocity of the inherent motion at any point depends on how much it has increased as a result of accelerating all the way in from infinitely far away as a result of its acceleration.

The amount of acceleration varies directly as the product of the amount of matter (mass and energy) making up the objects accelerating one another and inversely as the square of the distance between them in space (though the force is exerted by way of the inherent motion).

At any point in a gravitational field, therefore, the increase in the inbound velocity of the inherent motion is equal to the escape velocity at that point. That is, relative to space, the inherent motion is moving toward the concentrated matter at the velocity of light plus a velocity that is equal to the outbound velocity a material object would have to have at that point relative to space to escape gravity and eventually come to absolute rest outside its influence. The decrease in the outward-bound velocity of the inherent motion in space is likewise the escape velocity, making the outward bound velocity of the inherent motion the velocity of light minus a velocity equal to the velocity a material objects would have to have to move outward and just escape the gravitational filed.

Since the gravitational variation in the velocity of the inherent motion at different points in space is equivalent to the acceleration of the inherent motion, any matter that coincides with space by way of the inherent motion also accelerates at the same rate. That includes, as we shall see, all forms of matter.

Photons are accelerated because they coincide with space in such a way that they are carried along by the inherent motion in space.

Material objects also coincide with space by way of its inherent motion. This is implicit in the spatiomaterialist explanation of the truth of STR. What makes it impossible to detect its velocity relative to the inherent motion experimentally are Lorentz distortions that material objects suffer because of their motion relative to the inherent motion. Indeed, some of those distortions depend on the difference in the one-way velocities of light in opposite directions in the direction of its motion relative to the inherent motion. Thus, when the inherent motion itself is accelerating inward, any material object that coincides with space by way of the inherent motion is also accelerated in the same way. And since electric charges move with the material objects and exert their forces by way of the inherent motion, their electric fields are accelerated along with them.

Since acceleration of matter by way of the acceleration of the inherent motion is a form of potential energy, the gravitational field is itself a form of matter. It is the form of matter I called “gravitational matter” at the beginning of the ontological explanation of the truth of the laws of physics (see Forms of matter), and the quantity of matter involved in constituting the potential energy of gravitational field is counted as part of the total matter (mass and energy) accumulated at the center of accumulation. Thus, as the kinetic energy of material objects increases because of their acceleration, the potential energy not only declines, but becomes less than zero (or maximum potential energy), and the total quantity of mass and energy is, thereby, conserved.

If the center of matter accumulation itself is in motion relative to space, then it already has a velocity relative to the inherent motion in space and all the effects of its gravitational field are affected accordingly.

Gravitation involves, according to this ontological explanation of the truth of the general theory, a second interaction between space and matter. The first was the reaction of space to material objects that acquire a high constant velocity relative to the inherent motion: it imposes the Lorentz distortions on such material objects. The second is more complex, because matter first causes a change in space, and then space, in turn, causes a change in matter. That is, accumulations of matter accelerate the inherent motion in space toward themselves, and the acceleration of the inherent motion not only accelerates the bits of matter it contains, but also changes the velocity of light at any point in space (because the inherent motion accumulates inward velocity over the entire gravitational field). It is as if space had a compound effect on the matter it contains, because either effect can occur separately, and both can happen at once.

The first effect occurs separately when material objects have a constant velocity relative to the inherent motion outside of a gravitational field.

The second effect occurs separately when material objects are at rest relative to the inherent motion being accelerated into a center of mass that is at rest in absolute space.

Both effects occur either when material objects have a constant finite velocity relative to an inherent motion that is being accelerated into a center of gravity that is at rest, or when the accumulation of matter itself has a constant velocity relative to the inherent motion in space outside gravitation.

Let us consider the consequences of this additional assumption about the nature of space and matter.

This ontological assumption explains why Newton’s law is approximately true in all those areas where it is recognized to be a good approximation, because it differs from Newton’s theory only in its assumption that gravitation acts by way of the inherent motion, that is, that it accelerates the surrounding inherent motion in space and that it does so as a force that is itself propagated by that inherent motion.

It also explains Einstein’s equivalence principle ontologically. It entails that local experiments on free falling frames come out the same as on inertial frames outside gravity, for in both cases they have a constant velocity relative to the ether.

But the spatiomaterialist theory also explains intuitively certain new phenomena used to confirm Einstein’s GTR, including the three new kinds of phenomena that have been used to confirm the general theory as well as the predictions about black holes.

Variation in the velocity of light. The most immediate effect of the acceleration of the inherent motion is on the velocity of light. The photon coincides with space by having some direction in the inherent motion wherever it is located and being carried along by the inherent motion in space. Thus, the motion of the photon relative to space manifests the inherent motion in space any motion that the inherent motion itself has relative to space because of the gravitational field.

Since the inherent motion is different at different locations in space as a function of the force of gravity, a photon traveling inward toward the center of matter will accelerate as it moves, acquiring a velocity relative to space that is higher than the velocity of light outside of the influence of gravitation. Correspondingly, a photon moving outward will leave the center of mass with a velocity relative to space that is less than it would have outside of gravitation, and it will accelerate all the time it is moving outwards until it reaches the velocity of light outside gravitation just as it escapes the gravitational field.

The quantity of the increase (decrease) in the velocity of light at any point in space relative to what it would be if there were no gravitational force depends on the escape velocity, that is, how much velocity a bit of matter would acquire as a result of being acted on by the gravitational force as it moves across the gravitational field.

Consider for simplicity’s sake a center of matter (mass and energy) that is at rest in absolute space. The theory is that when matter accumulates in space, it acts on the surrounding space in a way that is equivalent to accelerating the inherent motion in space toward it, giving the inherent motion itself a velocity relative to absolute space. The rate of acceleration is determined by the force of gravity (which declines as the square of the distance from the center of gravity), and that means that the photon starts accelerating infinitely far away from the gravitating body and accumulates speed as it continues to accelerate inward (with its rate of acceleration becoming greater as the gravitational force increases), so that at points nearer the center of gravity, the photon has an instantaneous, inward velocity that is equal to the velocity of light outside gravitation plus the escape velocity at that point in the gravitational field.

If the gravitating body is not at rest in absolute space, but is itself moving relative the inherent motion in space, that will also alter the velocity of light the same way at every point throughout its gravitational field.

When enough matter accumulates to accelerate the inherent motion itself to a velocity in space that is faster than the velocity of light outside any gravitational field, it is called a “black hole.”xxxix The so-called Schwartzschild radius of a black hole at rest in space is the surface in space at which the inward velocity of the virtual inherent motion equals the velocity that light would have in that direction at that location, if the inherent motion were at absolute rest. Inward-bound light crossing that surface would have a velocity relative to space twice what light would have outside of gravitation, and thus, it is impossible for light being carried in the opposite direction by the inherent motion to cross that surface. Outward bound photons at the Schwartzschild radius of a black hole would be at rest relative to space.

Gravitational bending of light rays. The effect of the acceleration of the inherent motion on the velocity of light explains the most famous new prediction of the general theory, namely, the bending of light rays in a gravitational field.

Given that light, as a form of energy, has a mass and exerts a gravitational force, Newton’s law can be used to predict that light will be bent from its straight path by the force of gravity, much like a material object. But the general theory of relativity predicts that the light ray will be bent at about twice the rate predicted by Newton’s theory. And in a famous expedition in 1918, Eddington found that Einstein was correct by measuring the direction of a ray of light from a distant star as it passed behind the sun during an eclipse and the distant star could be seen.

The greater effect of gravitation predicted by Einstein is what would be expected on the spatiomaterialist explanation of gravitation, because two factors are involved in determining the pathway of the photon.

First, as the light ray passes the gravitating body, it is pulled sideways into the center of gravity by the inward acceleration of the inherent motion in the transverse direction, which diverts it from a straight path, much as expected on Newtonian grounds.

Second, as the photon is approaching the center of gravity, the inward acceleration of the inherent motion gives light an inward velocity higher than it would have outside the gravitational field. But since the inherent motion on the other side of the center of gravity has been accelerated in the opposite direction, the photon slows down as it passes the gravitating body to a velocity that is lower than it would be outside gravitation, and then it gradually speeds it up again to the normal velocity of light relative to space as it moves out of the gravitational field on the other side. The result of these changes in the velocity of light is that the photon spends a disproportionately longer period of its entire trip near the center of gravity where the sideways acceleration of the inherent motion toward the center is greatest than it does farther away when the sideways acceleration of the inherent motion is minimal. That explains the higher value of bending predicted by Einstein.xl

Time delay in radar signals. The effect of the acceleration of the inherent motion on the pathways of photons can also explain the time delay in radar signals reflected back to earth from planets on the far side of the sun when the paths of those signals lie near the sun.

There is a spatial symmetry about the velocity changes that occur both times the radar signal approaches and recedes from the sun. The signal gains velocity as it approaches the sun, because the inherent motion is accelerating under gravity in that direction. But it quickly comes to have a lower velocity than light outside of gravitation as it passes by the sun, because of the inbound acceleration of the inherent motion on the other side of the sun. And then the signal regains velocity as it recedes, because the inward velocity of the inherent motion on the other side is lower the father away from the sun.

It might seem that there should be no net effect on the total time it takes for the light signal to pass by the sun, because the higher velocity of its approach to the sun will be canceled out by the lower velocity of its retreat from the sun on the opposite side. After all, the approaching signal travels just as far at each higher velocity as the receding signal travels at comparably lower velocities.

There is, however, a net slowing down of the period required for the entire trip, because the equal distance on each side of the sun entails that the light signal spends more time traveling at slower velocities than it does traveling at faster velocities. Hence, it cannot make up all the time it loses going slower in the time it spends going faster. This happens both ways on its round-way trip to the distant planet, causing an overall delay in the radar signal’s return that does not occur when its path is not near the sun.xli

Time dilation caused by acceleration relative to the inherent motion. Another famous prediction of Einstein’s general theory of relativity is the so-called “gravitational red shift,” or a time dilation in gravitational fields. That is, all physical processes on material objects are slowed down at a rate that depends on the potential energy of the gravitational field (which would vary directly with the altitude, if the force of gravity were constant). It predicts that such a time dilation will be observed both in objects at rest in a gravitational field and in objects in free fall in a gravitational field.

Gravitational time was observed by Pound and Rebca (1960) demonstrating a difference in the rate of oscillation of iron nuclei at the top and bottom of a tower at Harvard.

It was also observed in signals sent by a hydrogen maser shot up above the earth and allowed to fall back by Vessot (1980).

Gravitational time dilation can be explained by the spatiomaterialist theory of gravitation, but it implies that physical processes are actually slowed down only when material objects are at rest in a gravitational field. Objects in free fall in a gravitational field are not affected. But there is an appearance of a time dilation in objects in free fall that is caused by the change in the velocity of the light by which the speed of falling clocks is observed. Let us, therefore, consider each case separately.

Real gravitational time dilation. The principle of equivalence implies that material objects at rest in a gravitational field will suffer a time dilation, and the ontological explanation of the equivalence principle according to the spatiomaterialist theory of gravitation implies that the rate of time dilation is proportional to the energy that would be required to accelerate the object to keep in at rest given its velocity relative to the inherent motion.

This distortion is like the Lorentz time dilation, except that it depends on resisting the gravitational acceleration of the inherent motion rather than having a constant velocity relative to it. According to the spatiomaterialist theory, a clock at rest in a gravitational field, for example, will be slowed down compared to a clock in free fall. If a free falling clock happened to have an initial upward velocity in a gravitational field like a ball thrown into the sky and it was synchronized with a clock at rest on its way up, then, when it passed the same rest clock again on its way down, the rest clock will have fallen behind by an amount that depends on the period between the measurements and the energy required each unit of time to resist the acceleration of the inherent motion and keep it from falling in gravity, given the velocity of the accelerated inherent motion at that point.

The “gravitational red shift” in objects at rest is usually explained as a consequence of Einstein’s equivalence principle. Consider two clocks at rest at different altitudes in a gravitational field and what happens to a regular signal (such as photons of a certain frequency) sent between them, say from the upper rest clock to the lower. (See Diagram of Gravitational red shift.) The equivalence principle implies that, when this interaction is observed from a free falling frame, it must obey the same laws that hold for inertial frames outside gravitational fields.

Consider, therefore, a free falling frame as long as the distance between the two rest clocks, and suppose that it had been shot upwards so that its inertial motion brings the top of the free falling frame momentarily to rest in space alongside the upper rest clock just as it sends a photon of a certain frequency toward the bottom rest clock. If the photon were intercepted by the bottom free falling clock, it would have the same frequency observed when it left, because that is what would be observed if the inertial frame were outside the gravitational field. But that is not how the photon would appear to the bottom rest clock, as can be predicted by observers on the free falling frame. All the time that the photon is traveling downward, the free falling frame is also accelerating downward, and thus, when the observer at the bottom of the free falling frame sees the photon being received by the bottom rest clock, that clock will be moving upward toward the photon. Such motion would cause a Doppler effect, and so the free falling observer predicts that the photon will be measured by the bottom rest clock as having a higher frequency than the photon sent by the upper rest clock. Indeed, this is what the rest observer does find, according to GTR and actual experiment.

In this case, it is a gravitational blue shift, but if the signal had been sent upward, it would be a red shift. (By the time the photon arrived at the top rest clock, the free falling frame whose bottom clock was momentarily at rest beside the bottom rest clock when the signal was sent would have accelerated downward, and so the top free falling observers would see the top rest clock as receding upward when the signal arrives, entailing the prediction of a Doppler red shift, that is, a lower frequency of light received by observer located by the top rest clock.)

What is the cause of the red/blue shift observed by the receiving rest clock?

GTR explains the frequency change by the spacetime curvature between the two clocks, but it does not say whether it results from a change in the frequency of light signals during the flight or a difference in the intrinsic rates of rest clocks at different altitudes. Will (1986, p. 49-50) says that “it doesn’t matter” whether the “light signal changes frequency during the flight” or the “intrinsic rate . . of the clocks change”, because there is “no operational way to distinguish between the two descriptions”.

Spatiomaterialism, however, cannot be indifferent, for it assumes that space and matter are substances that exist only at the present moment, and that means that the red/blue shift cannot involve any actual change in the frequency of signals as they travel across space through time. The frequency, or period between signals, cannot change, regardless how the velocity of light may change along the path, as long as each signal follows the same path in real time. The only possible spatiomaterialist explanation is that the frequency shift is an appearance due to an actual slowing down of the rest clock (and all processes involving material objects at rest).

Spatiomaterialism explains why the clocks at rest are slowed down by their relationship to the inherent motion. The inherent motion is accelerating at the location of the clock, which is evident in the free falling frame, and thus, the rest clock must be accelerated relative to it in order to keep it at rest. In order to understand the relationship between these two reference frames, let us consider the equivalent situation outside of gravitation according to the spatiomaterialist theory.

The relationship between these two reference frames in the gravitational field is not equivalent to one reference frame being accelerated relative to some inertial reference frame outside gravitation unless both frames are also in motion relative to the inherent motion in space, because at any point in a gravitational field, the inherent motion has acquired a certain velocity relative to absolute space. Thus, let us consider two reference frames outside of gravity that have the same velocity relative to the inherent motion as those in the gravitational frame, and let us suppose that one of them is accelerated relative to the other. In such a case, the Doppler effect would cause the same red (or blue) shift, depending on which way one frame was accelerated relative to the other during the brief interval of measurement.

Outside a gravitational field, the Doppler effect would not be interpreted as a time dilation, because it would be explained by the change in the velocity of one of the frame relative to the inherent motion due to its acceleration during the interval of measurement. The situation in the gravitational field is different because the acceleration of one frame relative to the other does not change the velocity of either one of them relative to the inherent motion.xlii Instead, it is the inherent motion itself that is being accelerated. Thus, the red (or blue) shift cannot be explained as a result of the change in velocity relative to the inherent motion due to the acceleration of the frame at rest in gravitation, as it is outside gravitation. It can only be the result of a slowing down of physical processes on the reference frame at rest in gravitation. Thus, it is a real time dilation.

Rest clocks at different altitudes in a gravitational field suffer different rates of time dilation, even though they may be resisting the same rate of acceleration in the inherent motion (as in a uniform gravitational field). This can be explained on the spatiomaterialist theory, because they have different velocities relative to the inherent motion. Outside a gravitational field, according to Newtonian physics, different amounts of energy are required for the same acceleration in objects when the objects have different velocities. The force per unit time is the same, but since at higher velocities, the force must be exerted over a greater distance, and thus, the energy consumed in exerting the force over that period of time is greater. That is, the rate of gravitational time dilation is proportional, not the force required to accelerate the rest clock, but to the amount of energy required. (At lower altitudes, the force has to act over a greater distance relative to rest in the inherent motion in order to keep the clock at rest.) This explains why the rate of time dilation is proportional to the potential energy for its location in the gravitational field (or the kinetic energy an object falling from outside the gravitational field would have at that point).

Apparent gravitational red shift. An actual gravitational time dilation occurs only when the clock is being accelerated against the acceleration of the inherent motion. A clock in free fall in a gravitational field will actually tick away at the same rate as a clock outside of the gravitational field. But a clock free falling in a gravitational field will appear to suffer a gravitational time dilation, because the motion of the clock across the gravitational potential means that any signals it sends out at regular intervals will be received later than they are expected, making it seem like the clock is slowed down.

Consider a clock in free fall sending signals out of a gravitational field. To observers outside the gravitational field, those signals will make it appear that the clock is suffering a time dilation, though it is not, because in addition to the normal Doppler shift expected from the velocity it acquires from free fall, signals sent back from lower altitudes will also travel the additional distance at lower velocities of light because the outbound velocity of light is lower (because the inbound velocity of the inherent motion is greater the closer it is to the center of gravity). Each signal will be delayed a bit longer than expected.

Or consider a clock shot upwards in a gravitational field that sends regular signals to earth (Vessot’s experiment). The signals received from the clock on earth will be affected by several factors apart from gravitation, including its location at the moment the signal is sent and its instantaneous velocity. These factors can be calculated and compared with the signals actually received. The actual signals will seem to be arriving sooner that expected the higher the clock goes, making it seem that the clock must be speeding up as it rises out of the gravitational field. But that is not proof that objects in free fall suffer a time dilation. Instead, it merely indicates that the light signal is traveling faster toward earth than the velocity of light outside of gravitation, and the higher the clock rises, the more different this factor makes (though the effect decreases as the altitude increases, because the signal travels the additional distance at a velocity that is closer to what it is outside gravitation).

The spatiomaterialist explanation of gravitational time dilation in general relativity resembles its explanation of the global equivalence of inertial frames in special relativity, because in both cases it recognizes both real and apparent distortions.

In special relativity, the Lorentz distortions are real in inertial frames that are moving relative to the inherent motion. But to observers on such a moving inertial frame, the inertial frame at rest relative to the inherent motion appears to be suffering Lorentz distortions. (The appearance is caused, as we have seen, by the mis-synchronization of clocks on the moving inertial frame and how that combines with its real Lorentz distortions.)

In general relativity, the gravitational time dilation is real material objects that are at rest in a gravitational frame, because that is how accelerate reference frames are related to the inherent motion. But free falling clocks appear to be suffering a time dilation, because as the clock falls, the signals travel pathways from the clock to the stationary observer at various velocities that are either faster or slower than the velocity of light outside of gravitation, depending on where the is located when the signal is sent.

Propagation of the gravitational force through the inherent motion. The final famous prediction of Einstein’s general theory of relativity is precession of the perihelion of Mercury’s orbit around the sun As Mercury orbits the sun, the main axis of its elliptical orbit rotates slowly around the sun (in the same direction as Mercury itself). It is a very small rotation (about 43 seconds of an arc per century, setting aside the other perturbations that Newtonian physics can also explain. This phenomenon also has an explanation in terms of the acceleration of the inherent motion in space according to the spatiomaterialist explanation of gravitation.

The gravitational force is exerted by a center where matter has accumulated by way of the inherent motion, that is, at the outbound velocity of light in the inherent motion it affects. The force is like a pulse of attraction propagating outward from the gravitating body, accelerating the inherent motion toward itself wherever the pulse reaches. The force is steady, because one pulse follows another continuously. But the gravitational force exerted anywhere in the field imposed by these pulses is exerted locally, by the inherent motion though which matter of any kind coincides with space at that point.

Gravitational waves. It helps to have a concrete model of how the gravitational force is exerted, and so let us think of it as being exerted by a flow of outbound pulses through the inherent motion affecting the velocity of inherent motion itself that it passes through. That will enable us to see why there are gravitational waves, as predicted by Einstein’s general theory of relativity.

When a gravitating body is at rest in space, its force field is basically spherical. The center of matter exerts a gravitational force on the surrounding space by way of the inherent motion (at the velocity of outbound light in it), and the acceleration it imposes on the inherent motion itself falls off at the square of the distance. Though the acceleration felt at any point in the gravitational field depends on a force that started propagating from the central body earlier, the acceleration at that point does not change over time, because each pulse of gravitational force is followed by another pulse the next moment.

At any point in the field, the arrival of a gravitational pulse accelerates the inherent motion inward (increasing its inbound velocity as it pulls it inward), but the pulse then moves on to the next location in space and does the same thing to the inherent motion located there. At each moment at any point in space, the inherent motion itself that arrives from farther out (because of the last pulse) is subject to the next pulse of gravitation, and so the inherent motion itself is accelerated inward, giving it a higher inbound velocity as it moves closer to the gravitating body. The gravitational field is, therefore, like a flow of gravitational pulses outward in the inherent motion everywhere pulling the inherent motion itself toward the gravitating body. Thus, it is a steady gravitational force field, which would affect objects in the way Newton’s law predicts.

However, when a gravitating body is moving back and forth across space (for example, when a pair of dense astronomical bodies are in orbit around one another), the pulses of forces propagating outward from the gravitating body come from different locations from one moment to the next, and thus, there is a wavelike change in the acceleration of the inherent motion at a distance. Thus, any material objects located there will feel a gravitational force that is changing directions from moment to moment.

Since the gravitational wave can accelerate material objects, it carries potential energy across space, and thus, it is a form of matter (which we are calling “gravitational matter”). If the gravitational field were imposed by a gravitating body at rest in space, the gravitational matter constituting it would be counted as part of the total quantity of matter (mass and energy) accumulated at its center (because the gravitational force is accelerating the inherent motion toward itself). But the gravitational matter making up waves is not counted in the rest masses of the gravitating bodies generating it (because the gravitational force is not accelerating the inherent motion toward itself. Thus, gravitating bodies lose energy as they exert gravitational waves. (The astronomical bodies orbiting one another will slow down and eventually fall into one another.)

Precession of the perihelion of Mercury. This explanation of how the force of gravitation is exerted can explain the precession of the perihelion of Mercury (or any planet around a star). The inherent motion itself is accelerated by gravitation, and thus the force of gravitation that is felt by any bit of matter depends on the acceleration of inherent motion in the part of space where it is located at the time.

Since the sun is so much more massive than Mercury, we can treat it as if it were at rest in space. Thus, although it is sending out pulses of gravitation through the inherent motion that accelerate the inherent motion it reaches towards itself, the gravitational field is basically spherical, with the strength of the gravitational force falling off at the square of the distance. This is the gravitational field through which Mercury moves.

Mercury is moving roughly perpendicular to the sun’s radial force field, and if that were all that determined the gravitational force that Mercury feels, Mercury would follow the pathway predicted by Newton’s law of gravitation (because its being the result of a pulse of gravitation propagating from the sun does not make any difference to the force that Mercury feels).

Mercury is also, however, another gravitating body. It is sending out pulses of gravitational attraction radically in the inherent motion, accelerating the inherent motion itself towards itself. Insofar as its pulses are oriented in the same direction as those propagating radially from the sun, this will make no difference, because Mercury’s force will be acting on an inherent motion that is everywhere being accelerated toward the sun. However, Mercury will also be accelerating the inherent motion toward itself in directions perpendicular to the sun’s radial forces. And since the sun’s radial pulses of gravitational forces travel by way of the inherent motion, they follow the path of light rays, and since Mercury will be bending light rays that pass by it (just as the sun does; see Gravitational bending of light rays), Mercury will be bending the sun’s pulses of gravitational forces toward itself as they pass by.

The acceleration of the inherent motion toward Mercury changes the location of the sun’s gravitational forces, but not the direction in which those forces accelerate bits of matter. As radial forces, they are normally pointing at the sun. But consider what happens to the inherent motion ahead of Mercury as it moves perpendicular to those radial forces. As it accelerates the inherent motion toward itself, it shifts the location of the inherent motion itself (the bending of the light rays), and thus, the gravitational force that would be exerted in those parts of space are no longer directed at the sun, but are slightly offset. They point to a location relative to Mercury that the sun would otherwise have only later in its orbit. Thus, when Mercury coincides with the part of space in which the displaced inherent motion is located, the force of gravitation will not be in the direction of the sun, but slightly offset.

To be sure, there is a symmetry about the acceleration of the inherent motion in front of Mercury and behind in its direction of motion. After all, light rays are bent towards it as they pass either in front or behind Mercury. But there is an asymmetry caused by Mercury’s motion. It is moving toward the inherent motion accelerated towards it in front, and it is moving away from the inherent motion accelerated towards it from behind. Thus, Mercury is affected by the displaced gravitational forces ahead of it, because it is moving into the parts of space where they are located. And it is moving away from the parts of space where the displaced gravitational forces behind it are located.

The net effect of the asymmetry caused by Mercury’s motion into the inherent motion it has accelerated towards itself in front of it as it moves is that its change of location relative to space amounts to a greater change of location relative to the inherent motion. The gravitational pulses, like light rays, are pulled closer together in front of it, so that its velocity relative to space makes a greater change in the direction of the gravitational force it feels than would otherwise be the case.

Since through its orbit, the direction of the sun’s force is always displaced in the same direction (as if Mercury were farther along in its orbit than it actually is), the sun’s gravitational force is always making Mercury change direction faster than it would otherwise, and thus, the orbit as a whole precesses around the sun in the same direction as Mercury itself.

The alteration in the direction of the effective gravitational force of the sun on Mercury is the major factor accounting for the precession, but there are two additional factors making it different from Newtonian expectations, which are relatively minor.

First, the propagation of Mercury’s pulses of gravitational attraction outward in the inherent motion is not quite at the velocity of light, because its acceleration of the inherent motion has given it an inbound velocity. In front of Mercury as it is moving though the inherent motion perpendicular to the sun’s radial acceleration, Mercury’s outbound pulses of gravitation have a velocity that is less than the velocity of light outside of gravitation by the escape velocity at each point in its outbound propagation.

Second, since Mercury itself is a material object, its motion relative to the inherent motion subjects it to Lorentz distortions, including a relativistic mass increase. Thus, it takes a greater gravitational force to change its direction.

Phenomena in Strong Gravitational Fields. The acceleration of the inherent motion in space is what replaces the curvature of spacetime in the spatiomaterialist explanation of gravitation. But we have considered mainly phenomena involving weak gravitational fields and velocities much slower than light, and its assumption about the nature of the gravitational force also explains other new GTR phenomena involving strong gravitational fields and high velocity.

In strong gravitational fields, for example, the velocity of the inherent motion itself (the ether) relative to space can approach the velocity of light mediated by the inherent motion, and thus, spatiomaterialism implies that a time dilation will occur even in free falling clocks, if they have a sufficient high velocity relative to the inherent motion in space.

Consider, for example, a free falling clock that is shot upwards out of a gravitational field so that it rises and falls back. At the top of its trajectory, the cock will be momentarily at rest relative to space, and even though it is not being accelerated against the gravitational attraction, it may be suffering a Lorentz time dilation. In this case, it would be caused by its constant velocity relative to rest in the inherent motion, which is rushing inward because of its acceleration by the gravitating body.

This Lorentz time dilation is different from the gravitational time dilation discussed above, which is caused by being accelerated in a gravitational field. But both factors may be contributing to the red shift that observers outside the gravitational field observe in light signals sent outward by such objects.xliii But since the Lorentz time dilation is a second order effect (a function of v2/c2), while the gravitational time dilation is a first order effect (a function of v/c), it doesn’t become significant until the emitter’s velocity relative to the inherent motion approaches that of light itself in the inherent motion. In strong fields, however, the Lorentz time dilation may be a more significant cause of red shift than the gravitational time dilation.

Indeed, material objects in strong gravitational fields with very high velocities relative to the inherent motion will suffer all the Lorentz distortions: length contraction, mass increase, and flattening of electric force fields, as well as time dilation.

I have already mentioned that the acceleration of the inherent motion can give the inherent motion itself (the ether) a velocity relative to space that is as great as the velocity of light outside gravitation (that is, in the ether). This is what happens at the Schwartzschild radius of a black hole. No light can escape a black hole, because everywhere on that spherical surface surrounding the black hole the outbound velocity of light mediated by the inherent motion is canceled out by the inbound velocity of the inherent motion itself. Any such photons would be at rest in space, even though they are moving at the velocity of light in the inherent motion.

Nor could anything else escape the black hole, since doing so would require moving through the inherent motion faster than the velocity of light. That is why it is called an “event horizon”.

Free falling material objects cannot even be momentarily at rest at the Schwartzschild radius, for the Lorentz distortions caused by their velocity relative to the inherent motion at that point would require their lengths to be zero, their physical processes to have stopped, and their masses to be infinite.

Inside the event horizon, light traveling any direction in the inherent motion would have an increasing velocity relative to absolute space toward the center of the black hole. And any bits of matter being accelerated by that acceleration of the inherent motion would move and interact with one another as they do outside gravitational fields (except for tidal forces, which bring their radial pathways closer together), as implied by Einstein’s equivalence principle. But when the bits of matter reach the center of the black hole, they must come to a stop. Physics does not say what happens then. Material objects cannot withstand the forces on them at the center, and presumably, they would collapse spatially, making the gravitational forces infinite. Thus, the center of a black hole is aptly called a “singularity” in absolute space.

Since neither light nor gravitational pulses can propagate outbound from beyond the Schwartzschild radius, the only indication of the amount of matter that has fallen into the black hole is the size of the Schwartzschild radius.

Spatiomaterialism can also explain what is happening around rotating black holes. Rotating black holes are formed by matter spiraling in, and there is an asymmetry about the gravitational field they set up which draws bits of matter falling toward the back hole in the direction of its rotation.

The reason is that the force of gravitation exerted by matter falling into a black hole propagates outward at the velocity of light in the inherent motion, and since at the Schwartzschild radius, the inherent motion itself is moving inward at the velocity light would have in the inherent motion if it were outside gravitational influences, only the forces propagated outward just before passing across the radius have an effect on the inherent motion outside. And since the matter is spiraling past the Schwartzschild radius, it has a greater effect behind than in front of its direction of motion. Thus, other bits of matter in that region of space feel an attraction that is not directly into the black hole, but which pulls it around the black hole in the direction of the matter that preceded it.

Empirical equivalence of different models of the general theory of relativity (GTR).This explanation of the old and new gravitational phenomena has assumed that nothing exists but two, opposite kinds of substances enduring through time. But the capacity of spatiomaterialism to explain those phenomena does not necessarily mean that it is equivalent to a single model of GTR on the received geometrical interpretation (which explains gravitation as a curvature in four dimensional spacetime). Thus, it remains to be seen why there are infinitely many different, observationally equivalent models of GTR for any particular universe, or why “general relativity” (in one sense) seems to be true.

Since this explanation of gravitation is based on the spatiomaterialist explanation of the truth of STR, space is assumed to be a substance, and we are liberty to take as our reference frame the inertial frame at rest in space outside of gravitational influences where the one-way velocity of light is the same both ways in every direction. That inertial frame is at rest relative to the inherent motion in space, and the inherent motion itself is at rest relative to space (in other words, that inertial frame is at rest relative to the ether, which, in turn, is at rest relative to space). The times and places of events assigned by observers on such an “absolute reference frame” would be accurate, because his clocks would not by mis-synchronized

Consider a gravitational field imposed by a gravitating body of some kind. It will be accelerating the inherent motion (or ether) toward itself according to the inverse square law. Of all the reference frames that would be accelerated toward the gravitating body, the one with the most accurate times and places of events would be the one that is at rest relative to the inherent motion itself (or the ether) as it is being accelerated toward the center of gravitation. To be sure, such a reference frame could not have clocks synchronized everywhere, since any large rigid object would be torn apart by the difference in forces acting at different points. But if observers on that reference frame could use GTR (or this ontological explanation of the gravitational force) together with light signals received from other objects to figure out where and when events occur throughout the gravitational field. That is, they would determine the “simultaneity hypersurface in curved spacetime” from their reference frame, and since that would correspond to what is really happening to substances at that moment as they endure through time, their reference frame can be called the “absolute model” for GTR, by analogy to the inertial frame of the absolute observer in STR.

The reason that there are many different empirically equivalent models for any such situation is that there are other reference frames which differ from the absolute reference frame only by have a velocity relative to the inherent motion itself that is being accelerated inward. They are empirically equivalent locally, because they suffer Lorentz distortions that mask their velocity relative to the inherent motion. And observers on each of them could use GTR together with information received from events elsewhere to determine their “simultaneity hypersurface in curved spacetime.” They would all disagree with one another, like different inertial observers outside gravitation, and there would be no way for them to tell by experiment which reference frame was the absolute reference frame.

That is, each possible model of GTR is adapted to the trajectory of one of the many different particles that could be in inertial motion at any point, and their different velocities relative to the inherent motion would give them, incipiently, at least, different standards of simultaneity (that is, each determines a different “simultaneity hypersurface in curved spacetime”). Any pair of such reference frames may have a high velocity relative to one another as they pass one another at that point, but each would observe Lorentz distortions occurring in the other reference frame, and thus, the symmetry between them would make it impossible to for them to tell which reference frame is at rest relative to the inherent motion in space that is being accelerated toward the center of gravitation.

This explains why models based on different reference frames are empirically equivalent as far as different velocities relative to the inherent motion is concerned. But neither can anything known about the effects of the gravitational force be used to distinguish one reference frame from another. Even of observers on the reference frames accepted the spatiomaterialist explanation of the nature of gravitation as an acceleration of the inherent motion by the gravitating body, that would not single out the absolute reference frame from the rest. (Or if the observers think in terms of GTR and see gravitation as a “curvature of spacetime” caused by gravitating bodies, that does not compromise their empirical equivalence.)

The absolute model cannot be assumed to be the one based on the local inertial frame that would result from accelerating all the way in from being at rest outside the gravitational field, for the gravitating body may itself have a non-zero velocity relative to the inherent motion in unstressed space.

It might seem possible to measure an object’s velocity relative to the inherent motion by using the gravitational time dilation of objects at rest in the gravitational field to determine their velocity relative to the inherent motion. But that will detect only the increase in the velocity of the inherent motion as a result of being accelerated toward the center of gravity to that point from outside the gravitational field, and that will not determine whether the gravitational field itself is in motion relative to the inherent motion outside gravitation.

Or it would be possible, in principle, to use the difference between light signals and gravitational signals to detect absolute rest, if gravitational forces propagated at a different velocity from light. But since the force that accelerates the inherent motion in space propagates through the inherent motion at the same velocity as light, its effects are explained equivalently by each model in the same way as light.

The equivalence of inertial frames that Einstein meant by “general relativity” can be explained, therefore, by special relativity. That is, the empirical equivalence of different models of GTR can be explained as the empirical equivalence of local inertial reference frames that have different constant velocities relative to the accelerating inherent motion. There is no way to determine which of their standards of simultaneity is correct, for there is no way to detect rest relative to the inherent motion. And none of the interactions between space and matter that constitute the force of gravity betrays which reference frame is the absolute model.

Though gravitation just happens to work in such a way that absolute rest relative to the inherent motion cannot be detected, the fact that it works that way could explain why Einstein was able to deduce his law describing the unexpected effects of gravitation from the assumption that all different local inertial frames are equivalent, or “general” relativity.

The spatiomaterialist explanation of gravitation has been presented as an ontological explanation of the truth of Einstein’s general theory of relativity. Since what is crucial to such an ontological explanation is identifying the aspects of the substances constituting the world to which the theory corresponds, I have presented only a qualitative argument. I have shown how GTR could be true, even if nothing existed but substances enduring through time, and every possible photon has a determinate location and velocity in absolute space at each moment as it is present (because the inherent motion itself is accelerated and, thus, moving through space). Though I have said enough about the quantitative factors to make clear how it would predict the same quantitatively precise measurements, I have not shown mathematically that it is equivalent.

That is an exercise I leave up to mathematically inclined readers. It affords an opportunity to refute ontological philosophy, for if it can be shown that there is no way that the acceleration of the inherent motion in space can yield the quantitatively correct predictions for all the relevant phenomena, we will have defaulted on the mortgage we took out to use spatiomaterialism as the foundation for the necessary truths of ontological philosophy, and the project will have failed. I see not reason to belief that that can be done. But like any basically empirical argument, ontological philosophy is vulnerable to empirical falsification, and thus, it must stand up to such challenges.

We can also see, at this point, why philosophers of science have not recognized the superiority of substantivalism about space to substantivalism about their spacetime. Instead of inferring to the best ontological explanation of everything in nature, they have let their ontology be determined by realism about the highly mathematical theories that physics has accepted as the best efficient-cause explanation of what happens in nature. Philosophers of spacetime simply assume that every theory about space and time, including Newton’s (and, thus, spatiomaterialism), can be represented as just another variety of spacetime theory using differential geometry.xliv

What spatiomaterialism offers, however, is a different kind of model of GTR. It explains ontologically why Einstein’s field equations are true by showing how gravitational phenomena can be constituted by space and matter as substances that exist only at the present moment. To treat spatiomaterialism as the belief in a “simultaneity hypersurface in a four dimensional spacetime manifold” is to abstract from such basic ontological issues as the nature of existence and time and to judge these theories only as efficient-cause explanations, that is, by their predictions of precise measurements.xlv

And when we judge all these theories by their capacity, as ontological theories, to account for everything observable about the world, including real change, the empirical superiority of an ontology of enduring substances is obvious, as we have seen, because of its explanation of the nature of time and existence.

Spacetime, whether curved or flat, cannot explain how the present is different from the past and the future, because spacetime cannot be a substance enduring through time as long as time is part of its structure. Thus, neither can it explain real change, because nothing ever comes into existence as time passes nor goes out of existence. (And as we have seen, attempts to avoid falsification by our experience of real change by adding subjective substances to the ontology makes it more complex encounters problems relating eternal and enduring substances as a single world, and is in any case ad hoc.)

Spatiomaterialism differs ontologically from Einstein’s GTR in just the way required to explain real change. Though it explains gravitation in much the way Einstein proposed — as an effect of the container of material objects on the path they follow — it replaces curved spacetime with an acceleration of the inherent motion itself. Since that is nothing but an aspect of space and matter as substances enduring through time, given how they are related, it explain why the present is different from the past and the future and “real change” is ontologically possible.

Quantum Mechanics. Quantum mechanics is the other great revolution in contemporary physics. Classical physicists would have admitted that the existence of ordinary material objects is a phenomenon that still needed an explanation, and as it turns out, that explanation came with the quantum revolution. Not only does quantum mechanics describe the electromagnetic forces responsible for the structure of all ordinary objects down to molecules and atoms, but the mathematics that is now used (in a gauge field theory called "quantum electrodynamics") is the model for explaining even the short-range forces (the strong and the weak forces) which responsible for the nucleus and deeper structure of material objects. The issues involved in explaining the truth of quantum mechanics is taken up in this chapter, and the two short-range forces, along with the basic particles of physics, will be explained in the next. The challenge posed by quantum mechanics and what is at stake in explaining its truth ontologically are discussed in the first section, and the rest of the chapter suggests one way, at least, in which its truth can be explained by spatiomaterialism. But at the outset, it should be noticed that spatiomaterialism already provides an explanation of how those forces are related to gravitation.

One of the greatest current mysteries of contemporary physics concerns the relationship between the force of gravity and the other three basic forces of nature. The problem is that the electromagnetic force and the two short range forces are explained by the exchange of a distinctive kind of particle (the gauge boson, such as the photon, in the case of electromagnetism), and the general theory of relativity does not lend itself to representation as a gauge field theory. The most promising way to represent gravitation as the exchange of such gauge bosons (called “gravitons” in the case of gravitation) would incorporate all four basic forces and the objects on which they act. But this so-called “superstring theory” requires the postulation of ten or more dimensions to space, and it seems to be completely immune from possible empirical falsification. There is nothing to recommend it but the mathematical uniformity in the representation of all four basic forces of nature, and as we have seen exclusive reliance on mathematics does not necessarily lead to the best explanation. .

Spatiomaterialism offers a solution to this problem, if quantum electrodynamics and the two short range forces are explained as interactions mediated by the inherent motion in space (that is, space as the "ether"), as I have been assuming, because this ontological explanation of relativity theory would also explain how the other three forces are related to gravitation. Gravitation is not a gauge theory, because the gravitational force acts on the inherent motion itself, that is, on space, not on bits of matter directly. It is by changing the “medium” (or "ether" as a condition of space) in which gauge particles are exchanged that gravitation accelerates bits of matter. It is not necessary for centers of matter accumulation to exchange gravitons with individual bits of matter in the region to accelerate them.

What makes the problem of relating gravitation and the other forces seem so intractable is the assumption that it requires the discovery of a law of nature from which Einstein’s general theory of relativity as well as the gauge forces can all be derived. The discovery of a basic law covering all the basic kinds of interactions among bits of matter has long been the so-called “holy grail” of physics, and that is the assumption that has led to attempts to formulate a gauge theory of gravitation. It seemed that such a basic law of physics could be discovered only if gravitation could be represented mathematically in the same way as the other forces. That is the goal of superstring theory.

Spatiomaterialism would solve this problem ontologically, rather than mathematically. The solution does not require the discovery of a new law of nature from which all the other laws follow, but only an ontological explanation of the truth of the laws that have already been discovered, for that reveals how gravitation is related to the other three forces. We have seen how the truth of general relativity can be explained ontologically, and thus, if spatiomaterialism can explain the truth of the other basic forces of nature in terms of the inherent motion in space, there is an ontological explanation of the relationship between the two kinds of forces. It is the recognition of the inherent motion (or "ether") as an aspect of the essential nature of space that makes this possible. By contrast, the gauge field theories are, in effect, the attempt to represent space as nothing but the forces by which particles interact.

If the explanation is ontological, what makes the problem of reconciling gravitation and the other forces of nature seem so intractable is, once again, the empirical method of physics, that is, the method of inferring to the best efficient-cause explanations of what happens in nature (and letting ontology be determined by realism about its theories). It was inevitable that physics would eventually find itself in this predicament, because physics first became a science by taking advantage of the power of mathematics to describe regularities about change. By insisting on mathematical theories that make surprising, quantitatively precise predictions of measurements, physics was able to discover the most abstruse facts about how bits of matter move and interact with one another. That is what enabled modern physics to go beyond the ancient atomists in understanding the nature of the elementary objects. But despite the acuity of its vision of regularities, physics was blind to a more basic aspect of the world. It failed to recognize that the job of science is not just to describe the regularities by which it is possible to predict and control what happens in the world, but also to describe the basic substances that constitute those regularities (not just the particles to which they refer, but all the substances that cause them ontologically). It comes from a failure to recognize that ontology can be explanatory in its own right and that ontological-cause explanations are a deeper kind of explanation from efficient-cause explanations, that is, from the same oversight that led to the Einsteinian revolution in the first place.

The challenge of quantum mechanics.Like the Einsteinian revolution, quantum mechanics might also be thought to pose a challenge for ontological philosophy. The quantum revolution has also overthrown assumptions of classical physics about the nature of the world, and if spatiomaterialism were unable to explain ontologically why the laws of quantum mechanics are true, physics might provides a reason for denying that ontological philosophy can use spatiomaterialism as the foundation for doing philosophy in a new way, despite its explanation of relativity theory.

The quantum revolution does not, however, challenge spatiomaterialism in the same, direct way as relativity. Quantum mechanics has not led to any consensus among physicists about the nature of what exists that is incompatible with spatiomaterialism.

The Einsteinian revolution is generally assumed to be the discovery of something that directly contradicts spatiomaterialism. In contemporary physics, absolute space and absolute time have explicitly been replaced by spacetime. But absolute space and time are entailed by the assumption that space and matter are substances enduring though time. Thus, in order to defend the use of spatiomaterialism as the foundation for this philosophical argument, I had to show that what Einstein’s two theories imply about the world could be explained on the assumption that space and time are absolute.

The quantum revolution has not led to ontological beliefs that directly contradict spatiomaterialism. This is partly because there is no consensus among physicists concerning what quantum mechanics implies about the nature of what exists. There is no dispute about the laws themselves; they are among the most precise and highly confirmed in physics. But scientific realism about quantum mechanics does lead to general agreement in ontological beliefs. There are so many disputes about the kinds of entities that are required for the laws of quantum mechanics to be true and they are so intractable that most physicists beat a hasty retreat to their empirical method and take cover by simply pointing out that its laws are the best way of predicting and controlling the relevant phenomena.

To be sure, there are ontological interpretations of quantum mechanics that are incompatible with spatiomaterialism. For example, some philosophers take measurements in quantum mechanics (involving the so-called “collapse of the wavefunction”) to be an event that depends on a conscious mind coming to know something about the world, and that is to assume that mind is a fundamentally different kind of substance from matter, which is is a form of immaterialism that spatiomaterialism rejects. Another interpretation, called the “many worlds view,” interprets measurement in quantum mechanics (again, the collapse of the wavefunction) to be the occasion of the universe splitting into different universes in which each of the different possible outcomes of each measurement are realized, which is not compatible with the world being constituted by substances. However, the possibility of such views is hardly an objection to spatiomaterialism, as long as it is possible to give an ontological interpretation of quantum mechanics that is compatible with spatiomaterialism. Thus, the issue is whether all possible ontological interpretations are incompatible with spatiomaterialism. It was the universal assumption that Einsteinian relativity is incompatible with space being absolute that forced us to take out a mortgage on spatiomaterialism, promising to show how it can explain Einstein’s two relativity theories ontologically as a condition of using it as the foundation for ontological philosophy.

To be sure quantum mechanics did overthrow the classical view of the nature of matter. But that does not necessarily challenge spatiomaterialism, because spatiomaterialism is no more committed to the classical view of matter than it is to the classical view of space. The relevant issue is whether it is possible to explain the truth of the laws of quantum mechanics by making assumptions about the nature of matter (and space) that are consistent with spatiomaterialism.

Materialism in general is not generally thought to be what is refuted by quantum mechanics. On the contrary, many physicists who are quite confident of the truth of quantum mechanics would consider themselves “materialists” in the broad sense in which that term is used to classify ontological positions.

The question is what more specific essential nature material substances must have in order for quantum mechanics to be true. It is clear that the regularities described by quantum mechanics cannot be explained ontologically by the kinds of material objects and light waves recognized by classical physics. But spatiomaterialism does not have to defend that view of matter. Indeed, as we have seen, its explanation of why the laws of classical physics are true (insofar as they are true) depends on assumptions about the nature of matter that are not part of classical physics. I assumed, for example, that kinetic energy is a form of matter that exists in addition to the rest masses of material objects, and that potential energy is as form of matter (force field matter) that is already counted in the rest masses of the objects exerting the forces. And in explaining the truth of the special and general theories of relativity, I have made further non-classical assumptions about the nature of the world — for example, that there is an inherent motion in space and that it can itself be accelerated and have a velocity relative to space.

This is not to say that there is nothing puzzling about quantum mechanics. There are two, basically different ways that it might seem to challenge spatiomaterialism directly. One has to do with a long recognized indeterminacy about its predictions, and the other is a more recently discovered problem about action at a distance (deriving from Bell’s theorem).

Indeterminism. The laws of quantum mechanics do not describe nature as having deterministic causal connections among states of affairs. Those laws often imply only that, given everything that can be known about a given situation, any of a number of different states might follow (or precede) it. The most that can be done is to assign a probability to each of those possible outcomes.

This is fundamentally different from classical physics, for its laws were deterministic. As Laplace pointed out in the eighteenth century, if the basic laws of classical physics are true, then given a complete description of the current situation (even the state of whole universe), it would be possible, in principle, to predict any future state (or even any earlier state). The state of the universe (or any closed system) at any one moment determines its state at every other moment.

Even in very limited situations, the laws of quantum mechanics do not usually support such deterministic predictions. Given a complete quantum mechanical description of a situation, there is a range of possible events that can happen (such as what measurements will reveal), and there is no way of saying which one it will be (though it is possible to assign probabilities to the alternatives). Thus, physics no longer assumes that complete knowledge of the current state of the universe would make it possible to predict what would happen.

This lack of precise predictability comes from the nature of the Schrödinger equation. Its solution for a given situation is a wavefunction which is a complete quantum description of that situation (in pre-relativistic quantum mechanics). It describes precisely how the quantum system evolves as time passes, just like a wavefunction in classical physics. But the Schrödinger wavefunction is not classical, because it involves complex numbers (containing i, or the square root of minus one), and the space in which the wave is contained is a “configuration space,” which is a space with three times as many dimensions as there are particles involved in the situation being described. There is no obvious way to relate such a wavefunction to the natural world. The standard interpretation of the Schrödinger wavefunction takes the square of the amplitude of the wavefunction (for a single particle) in any small region of space to represent the probability of finding the particle at that location. (And there are mathematical operators on the wavefunction that predict measurements, but they cannot predict precisely both of any pair of complementary variables, such as the position and momentum of an electron.)

This limitation on precise predictions of what will happen is summed up in the famous Heisenberg uncertainty principle. This principle can be taken as reflecting either an indeterminism about the world itself or as merely an incompleteness in what can be known about it. Though in either case, it is a limitation in principle, rather than practice, a mere incompleteness in our possible knowledge about the world would not contradict spatiomaterialism. Substances enduring through time could still constitute causal connections, even if some aspects of those substances cannot be measured precisely. Furthermore, even if this uncertainty did derive from an indeterminism in the nature of what happens independently of how it is known, it would not necessarily be incompatible with spatiomaterialism.

Indeterminism would contradict spatiomaterialism if it was incompatible with the world being constituted by substances enduring through time. Such an extreme indeterminism would be true, if the predictions supported by quantum mechanics corresponded to all the causal connections that there are between the properties that hold at one moment and the those that hold at the next. To hold that what is unpredictable is not determined at all is incompatible with any explanation of the world as constituted by substances enduring though time, because it is to assume, in effect, that something comes from nothing. What is unpredictable about the next moment would not depend in any way on what existed at the previous moment, and since it would have to come from nothing at all, extreme indeterminism would contradict the assumption that the world (and all its aspects) are constituted by substances enduring through time. Though this does not bother epistemologically minded naturalists, it would be a death blow to ontological naturalism.

A less extreme form of indeterminism is compatible with an ontological explanation of the natural world, though it is still hard to swallow. Indeterminism might hold that what is unpredictable according to the Heisenberg principle is a result of an inherent randomness in the essential nature of the matter making up the world. This would be more than a mere limitation in what we can know about the determining conditions, because it also would be a limitation in what even God could know. There would be no need to believe that something comes from nothing, because what exists at the next moment would be constituted by the same substances that constituted the world at the previous moment. But here would be no aspect of the nature of those substances at the previous moment that determines which of certain aspects it will have the next moment, because the randomness would be an aspect of the essential nature of the kind of matter that constitutes the world. The randomness would be a temporally complex aspect of the essential nature of matter, for it would make the connections between properties that substances have at different moments random. It would be as if matter itself contained a randomness generator that even God could not use to predict what will happen (though God would presumably still know the future, since he is the creator of all the moments of the world). Though such a view about the nature of matter would be consistent with spatiomaterialism, it would not be as good as one that could give a genuine ontological explanation of what happens, that is, which explains what happens as aspects of the world that follow from the natures of the basic substances as they endure through time constituting the world.

However, The Heisenberg uncertainty principle does not preclude a genuine ontological explanation of what is unpredictable. To hold that quantum uncertainty is merely a limitation in what beings like us, who are parts of the world, can know about the world is to hold that what happens does have a cause, but that we cannot know precisely what it is. This is to interpret the probabilistic nature of quantum mechanics as an incompleteness in our knowledge, rather than as indeterminism about the world. It assumes that there is some “hidden variable” that is actually determining what happens, though for some reason, that variable cannot be measured. That is not incompatible with spatiomaterialism, because the reason for the Heisenberg uncertainty could be that the interactions required for scientists, as material objects in space, to know about particular conditions in the world so disturb the world that they alter the conditions being known. That limitation must, of course, be caused by the basic nature of those interactions. But that does not mean that it is impossible to identify the nature of the hidden variable. It means only that its quantity cannot be measured accurately in any particular case. And having inferred to spatiomaterialism as the best ontological explanation of the world, we may be in a better position to identify the nature of the hidden variable that makes quantum mechanics incomplete.

Bell’s theorem. Though the traditional puzzles about the apparent indeterminism of quantum mechanics do not necessarily contradict spatiomaterialism, there is a more recently discovered implication of quantum mechanics that may. It occurs when particles separate from one another in a way that gives them opposite orientations of a quantum property called “spin.” John Bell showed that when such particles move away from one another in opposite directions, it is possible for a measurement made of one particle at one location to predict (probabilistically) measurements that are made at another location more accurately than would be possible if the particles had the properties being measured from the time they parted from one another. These “Bell correlations,” as I will call them, seem to imply that spin is not a property that the particles carry with them locally, but one that depends on the entire system, including both particles rushing away from each other.

This suggests according to a standard interpretation of quantum mechanics that the measurement of one particle affects the other particle (that is, that such effects are part of what is called the “collapse of the wavefunction”). But if measurement does have such effects, then it would have to be able to have its effect faster than the velocity of light, and that seems to contradict the principle of local action. I have assumed that what happens in one part of space cannot affect what happens elsewhere any faster than the velocity of light, for that velocity is determined by the inherent motion in space.

There is, however, something suspicious about the Bell correlations. There is no other evidence of faster than light effects in nature. Furthermore, it has been shown that, whatever is going on, Bell correlations are the kind of signal that can be used to communicate information. They are peculiarly lacking in further consequences.

It is not clear, therefore, that this departure of quantum mechanics from Bell’s theorem (about what local action entails) depends on one measurement affecting the other measurement causally. However, worries about the possibility of action at a distance will probably not be put to rest completely unless it is explained how it is possible for quantum mechanics to make such predictions. Thus, there something that needs explaining.

There is, therefore, reason to explore the ontological explanations of quantum mechanics that are opened up by spatiomaterialism. We would be justified in using spatiomaterialism as the foundation for ontological philosophy without explaining why quantum mechanics is true. But if its explanation of the aspects of the natural world to which the equations of quantum mechanics correspond did help clear up the quantum puzzles, there would be an additional reason for believing that spatiomaterialism is true.

In the first section, I will review the traditional puzzles about the nature of matter posed by quantum mechanics.

In the second section, I will introduce several new assumptions about the nature of space and matter and show how they would enable spatiomaterialism to explain the forms of matter that were assumed in explaining the truth of the laws of classical physics.

The third section will return to the quantum puzzles and show how the proposed ontological assumptions would explain those puzzling phenomena ontologically, including a response to the challenge that seems to be posed for spatiomaterialism by the more recent discovery of Bell correlations.

This more detailed ontological theory about the nature of matter is offered in a speculative vein. It differs from the ontological explanation of relativity theory, because no such explanation must be given in order to use spatiomaterialism for philosophical purposes. And it differs from the arguments to come about global regularities, because they attempt to prove that certain proposition are ontologically necessary truths. The reason that this ontological explanation of quantum mechanics is not ontologically necessary is that there may be other ontological explanations of quantum mechanics that are also consistent with spatiomaterialism (and what is says about relativity theory). Thus, the most I would claim to show is that some such ontological explanation is true. It may not be this one, but it will be clear, I believe, that there is some way of explaining the truth of quantum mechanics on a spatiomaterialist foundation. And since speculation is valuable as a way of exploring the possibilities, this particular version of spatiomaterialism may contribute to the discovery of the more complete truth about the natural world.

This explanation of quantum mechanics is, like its explanation of relativity theory, ontological, rather than mathematical. I will be trying to show how the new phenomena predicted by quantum mechanics can be constituted by space and matter as substances enduring through time, not that there is a better efficient-cause explanation of what happens. It does not claim to make any new predictions of what happens in the world.

Though I will give reasons for believing that this ontological explanation is quantitatively accurate (or can be made so), I will not try to show in detail how the formidable mathematical formalism of quantum mechanics relates to the world. Such a mathematical argument would take us too far afield. And in any case, it has already been done by David Bohm. (See Bohm, 1993, with Basil J. Hiley.) That is, the ontology I will be proposing is a variation on the ontology that Bohm shows to correspond to the Schrödinger equation, the basic equation of quantum mechanics, and thus, if Bohm’s ontology is a possible explanation of the truth of quantum mechanics, then so is this one.

There are many good accounts of quantum mechanics, but a reasonably accessible one that I have recently found useful is Jim Baggott's The Meaning of Quantum Theory.

In most cases, it will be clear that the kinds of assumptions I will be making can be refined to made them quantitatively adequate. This is much the same attitude I took in explaining ontologically the truth of general relativity, except that in the case of quantum mechanics, I also leave open the choice between various more detailed, alternative ontological assumptions. Thus, in order to show that it is not possible to explain the truth of quantum mechanics ontologically in this way, it would be necessary to show that none of these possibilities can be quantitatively adequate for the whole range of quantum phenomena.

Nor do I claim that the ontological theory being presented here is the best spatiomaterialist explanation of quantum mechanics, only that it (or one much like it) is possible in the sense of accounting for all the relevant phenomena. There may be ways in which space and matter existing together as a world can explain the truth of quantum mechanics more simply. That would be interesting and preferable. But it is not the crucial point, because the possibility of such an ontological explanation is all that is relevant to rest of ontological philosophy. And seeing how it is possible is the first step toward discovering the best such theory.

Quantum puzzles. Of the various quantum puzzles, the most basic is probably wave-particle duality. The atom itself is, however, the most important, puzzling consequence for the ordinary world. The traditional way of summing up what is most puzzling about quantum mechanics is the Heisenberg uncertainty principle, but recently the most discussed is called “Bell’s inequality.” All of them are described here as a way of introducing quantum mechanics as it is currently understood, and after explaining the spatiomaterialist theory of quantum matter, I will show how they can be solved.

Wave-particle duality. According to Bohr, the basic puzzle of quantum mechanics is the dual nature of the basic entities it describes. They all appear to be like both particles and like waves. What classical physics took to be waves turn out to have a particle-like nature as well, and what classical physics took to be particles turn out to have a wave-like nature as well. Bohr thought that both appearances of the underlying reality are due in part to our measuring apparatus and the classical expectations on which they are constructed. But wave-like and particle-like natures are apparently incompatible, and since both of these classical conceptions of reality are needed to make all of the possible predictions, he called the basic puzzle of quantum mechanics “complementarity.” Bohr was the originator of the so-called "Copenhagen interpretation" of quantum mechanics, which holds that the reality behind these complementary phenomena is incomprehensible to us.

The particle-like nature of electromagnetic waves.Light has long since been thought to have wave-like nature in classical physics. Early in the nineteenth century, Thomas Young showed that light passing through two narrow, closely spaced holes (or slits) produces a pattern of light and dark lines on the screen that finally intercepts them, and he explained it by the wavelike nature of light. The places on the screen where the waves emerging from each slit interfere constructively are bright, while the places where they interfere destructively are dark. When one slit is blocked, the interference pattern disappears.

Diffraction phenomena also indicate the wave like nature of light. Light rays passing through a hole that approximates its wavelength will be spread out as it leaves the hole, with the range of the spread varying inversely with the size of the hole. When the hole is large, the light hitting the distant screen is like a point, but when the hole is small, the diffraction is great.

Moreover, as we have seen, light had been explained by Maxwell as the wavelike coupling of the electric and magnetic forces described by his equations. Indeed, it enabled him to predict the velocity of light.

The particle-like nature of light was the first of the discoveries that eventually culminated in quantum mechanics. Instead of propagating like a wave in an elastic medium, as the classical model assumed, it became clear that light is actually made up of distinct particles, which are now called “photons”. This particle-like nature means that the energy and momentum carried by light do not combine continuously, as they do in ordinary waves, but come in separate units, called “quanta”. The size of the quantum of light is now represented by Planck’s constant, h, which is part of every new equation used in quantum mechanics. It appears in the new equations for the energy and momentum of light. The energy, E, is given by E = hf (where E is energy, f is frequency), and the momentum, p, is given by p = h/ (where p is momentum, and is the wavelength).

Max Planck first discovered the particle-like nature of light in 1900, though he did not fully understand what he was on to. He discovered the constant named after him by tinkering with a classical equation for calculating the amount of energy given off at each frequency in so-called blackbody radiation, that is, a hot body in which no frequency of light should be favored. (It is best approximated by a box with mirrored interior walls in which light of all possible wavelengths for a box with certain temperature are being reflected back and forth.) The classical equation assumed that the frequencies of light being given off varied continuously from the lowest to the highest, with the peak intensity depending on the temperature. That assumption worked well enough for the low frequencies, but at high frequencies, it led to the conclusion that the total energy given off should be infinite. This absurdity was called the “ultraviolet catastrophe.” Planck discovered a formula that avoided the catastrophe and predicted the total quantity of energy given off at each frequency by introducing a constant, h, into the formula which restricted the frequencies of light. That is the source of the equation for the energy of light: E = hf. (Though its meaning is still obscure, it can, perhaps, be seen as requiring the photons to differ from one another by that constant amount.)

Albert Einstein made it clearer that what Planck had discovered was the particle-like nature of light by using Planck’s constant is his own explanation of the photoelectric effect (in 1905, the same year that he published his special theory of relativity). It had been known that light being intercepted by material objects could release electrons from the material objects, but it was found that the release of electrons did not depend on the total energy of the light waves (the intensity of the light), as one would expect on the wave hypothesis. It depends on the frequency of the light. Below a certain frequency, no electrons are released, regardless how intense the light may be at that frequency. Whereas light with a higher frequency would release electrons even though the intensity was much less. Einstein showed that the release of the electrons depended on the absorption of single photons, each of whose energy depended on Planck’s constant: E = hf.

Much later (in 1923), Arthur Compton showed that photons also have a momentum like particles. He shot high energy photons (x rays) at electrons and used arguments based on the conservation of momentum and energy to predict correctly the amount by which their energies would be changed by such scattering.

The particle-like nature of the light does not change its wave-like properties. Indeed, it turns out that interference effects still occur when light is sent through the two-slit apparatus one photon at a time. Over time, they still accumulate in fringes on the distant wall.

The wave-like nature of particles with rest mass.Material objects are understood in classical physics as having definite locations in space at each moment and to follow definite trajectories as they move from one place to another. But the behavior of objects with rest mass on the smallest scale is peculiar in the opposite way from photons, according to quantum theory. Just as light waves have a particle-like nature, so material objects have a wave-like nature.

The wave-like nature of particles with rest mass was predicted in 1923 by de Broglie. What Einstein’s special theory of relativity implies about the relativistic increase in mass leads to the conclusion that the energy of a photon is equal to the product of its momentum and the velocity of light, or E = pc. Since the velocity of light is equal to the product of the frequency and wavelength, or c = fit follows that the momentum of a photon is p = h/De Broglie went on to suggest that the same relationship holds of particles with kinetic energy. He argued that particles, such as electrons, protons and material objects with mass generally would also have a wave length that varied inversely with their momentum in the same way.

Interference and diffraction phenomena were the kind of empirical evidence that was taken as showing that light has a wave-like nature, and soon after de Broglie’s prediction, it was shown that the electrons forced to pass through very small holes do exhibit diffraction, that is, the smaller the hole, the more they spread out. Eventually, even interference phenomena were demonstrated with electrons. When electrons moving at a certain velocity are projected through narrow, closely spaced, parallel slits at a screen (where the distance between the slits approximates their de Broglie wave length), they also form an interference pattern on the far wall, as if they were waves. Even when the electrons were sent one at a time, they tended to land on the distant screen only along certain fringes, leaving lines between them without any hits. Thus, each particle is like a wave. The same has been show to hold for neutrons, though in the case of ordinary sized objects, the wavelengths are so small that interference effects are undetectable.

The structure of the hydrogen atom. The laws of quantum mechanics were discovered mainly by attempting to explain the structure of the hydrogen atom. It had been established by Ernest Rutherford that the atom is composed of a massive, positively charged nucleus surrounded by far less massive electrons, and Niels Bohr hoped to explain the chemical properties of atoms by the nature of the interactions between the electrons and the nucleus. It was clear that atoms could not be explained in classical terms on the model of the solar system, since according to Maxwell’s equations, the orbital motion of an electron would generate (as the acceleration of a negatively charged particle) an electromagnetic wave which would drain its energy until the electron was located at rest with the nucleus. In fact, atoms with electrons located around it are quite stable, and when such atoms are excited (by supplying energy to them), they give off electromagnetic radiation at a certain set of distinctive frequencies.

Bohr explained the frequencies of the spectrum of hydrogen atoms (in 1913) by assuming that electrons can have only certain orbits, each characterized by an energy level that corresponds to the total energy of an electron with kinetic energy in a force field with potential energy imposed by the nucleus. (The total quantity of energy is negative, because the kinetic energy of the particle is not great enough to replace all the negative potential energy that would be required to free it, and according to our assumption about the nature of potential energy, the negative sign for potential energy indicates that the nucleus and electron have less rest mass.) The energies of the possible orbits were determined as a function of Planck’s constant, and a number was assigned to each possible orbit, starting with the lowest energy orbit and counting upwards (n = 1, 2, 3, . . ). Bohr showed that the spectral lines of the hydrogen atom could be explained by the differences in the energies of these permitted electron orbits.

The basic puzzle of quantum mechanics is the structure of the atom itself, that is, what is going on that only certain energy levels are possible for electrons bound to a nucleus by electromagnetic forces.

Given the structure of the atom, however, there is another problem, for it does not seem possible that electrons could be jumping from one orbital to another. When a photon is absorbed or emitted by an atom, an electron changes from one permitted orbital to another (so that the atom changes from one energy state to another). But the photon has a particle-like nature, and the particle seems to change its position and motion in an instantaneous, step-like change, that is, without accelerating nor even moving continuously from one state to the next. It hard to see how the electron’s change of orbital can be explained as the motion of a material object, since a material object can change location only by moving across space continuously as time passes time.

Another puzzle has to do with the timing of the emission of photons. When an atom or molecule is in an energy state that can decay into a lower energy state, it is not possible, even in principle, to say exactly when it will decay. The timing can be assigned a probability, but the theory has nothing to explain why it happens at one moment rather than another within that range.

Electron jumps also seem to be involved in the phenomenon of tunneling. “Tunneling” refers to situations in which electrons seem to jump across barriers imposed by force fields. On classical principles, crossing such a force field would require more energy than the electron has. Nevertheless, some electrons do jump across. Only a few electrons do so, and there is no way to predict which ones will jump. But it is so regular that this phenomenon is used as a kind of microscope for mapping the surfaces of material objects.

Erwin Schrödinger thought that it would be possible to avoid these puzzles about electron jumps and explain everything deterministically by following up on de Broglie’s suggestion and explaining the behavior of the electron in an atom as a wave. Using the model of the classical equation for waves and taking the electron wave to be in a potential field, Schrödinger presented an equation in 1925 that explained the energy levels of the permitted orbitals of electrons in the force field imposed by the nucleus of the hydrogen atom. The time-independent Schrödinger equation (with the temporal changes factored out so that it represents only the spatial structure of the wave) portrays the electron bound to the nucleus of the hydrogen atom as a standing wave, like a plucked string on a guitar. This made it possible for Schrödinger to explain the numbers that Bohr had assigned to the permitted orbitals of electrons as the energy states in which the electron could be such a stable, standing wave. The lowest energy level corresponds to the string with no nodes (that is, half the wave length for its energy), the next one to a string with one node, and so on. The problem of quantum jumps seemed to be solved, because the transitions between such energy states of atoms were explained as smooth and continuous transitions of waves.

Schrödinger believed that his wavefunction showed that electrons were not particles at all, but could be explained purely as waves in an electromagnetic field. This did not explain why electrons appear to be particles, for example, how they leave vapor trails in a Wilson cloud chamber or interact at a certain point on the distant wall in the two-slit interference experiment. But it is possible to explain why electrons seem to have a determinate location by holding that they are a "superposition" of waves with slightly different wavelengths, because in regions where such wave interfere constructively, they clump together in what are called “wave packets.” Since the locations where such a set of waves interfere constructively have more or less precise locations in space and seem to move through the space occupied by the waves, the Schrödinger wavefunction could explain the appearance that electrons move like particles. (This was not a fully adequate explanation, however, because such wave packets also tend to disperse over time, and yet electrons actually turn up later at definite locations.)

However, it was not possible to interpret the Schrödinger wavefunction as the description of a classical wave. One problem was that it contained complex numbers. There is no way to measure quantities multiplied by the square root of minus one, and yet those complex numbers are essential to the wavefunction, since they describe the phases of the waves that are superimposed in the quantum system and, thereby, determine the interference phenomena.

Furthermore, the Schrödinger wavefunction described a wave in a space that can have more than three dimensions (or what is called “configuration space). When more than one particle is involved, the space occupied by the wave described by Schrödinger’s wavefunction has three times as many dimensions as there are particles. There is no obvious way to relate such an equations to the actual three dimensional world.

What is now the orthodox interpretation of the Schrödinger wavefunction was first proposed by Max Born in 1926. He took the square of the (time-independent) wavefunction in some region of configuration space to be a measure of the probability of finding that the particle located in that region of configuration space (thereby predicting a measurable property, such as location, momentum or kinetic energy). The predictions are confirmed by measurement.

Since the predictions are merely probabilistic predictions, however, Born took the Schrödinger wavefunction to be a representation, not of the world itself, but of what we can know about it. This avoided the problems of quantum jumps and wave packets that spread out, because what really happens is not knowable. And insofar as it is taken realistically, it implies that what happens is not fully determined by the state that precedes it.

Heisenberg uncertainty principle. An entirely different mathematical representation of these same quantum phenomena was developed by Werner Heisenberg. His “matrix mechanics” is basically an algorithm for making predictions of measurements without any attempt to explain what is going on beneath the observable surface. Though Schrödinger showed that Heisenberg’s matrix mechanics and his own wavefunction are mathematically equivalent, matrix mechanics makes the limitations on what can be known about the classical properties of the entities described by quantum mechanics clear. In arguing against Schrödinger, he defended what has come to be known as the Heisenberg uncertainty principle.

In matrix mechanics, there are pairs of variables called “complementary” or “conjugate” variables, because the measurement of one affects the measurement of the other. That is, the results of measuring one variable and then the other would be different if they were measured in the opposite order. The position and momentum of an electron are complementary variables, meaning that the position and momentum of an electron cannot both be measured with arbitrarily high precision But the more precise one measurement is, the less precise the other is. Using Born’s probabilistic interpretation of the wavefunction to express the “uncertainties” in such measurement, Heisenberg derived a general principle about complementary variables: the product of the uncertainty about the position and the uncertainty about the momentum cannot be less than Planck’s constant divided by four pi.

Heisenberg’s uncertainty principle holds in a parallel way for other conjugate variables, such as energy and time, angular momentum and orientation, and cycle and phase. In each case, one variable is more particle-like and the other is more wave-like, and thus, the variables are said to be complementary.

Heisenberg apparently took his uncertainty principle to be a basic postulate from which all of quantum mechanics could be developed. He rejected talk about the wave-particle duality and took a purely instrumentalist approach which simply denied that there is any aspect of the world that is not described by his matrix mechanics (or by their equivalents in using the Schrödinger wavefunction).

The equivalence of Heisenberg’s matrix mechanics and Schrödinger’s equation means that the Heisenberg uncertainty principle can be derived in a similar way from Schrödinger’s equation.

The solution of Schrödinger’s equation for a given situation yields a wavefunction, which is a complete description of the quantum system. But in order to predict a measurable property, it is necessary to apply an appropriate mathematical operator to the wavefunction. The operator yields an “expectation value” for that property, which may be a precise value or an average value.

But some pairs of operators are not commutable, such as the position and momentum of a particle. Though it is often possible to make precise predictions of these properties, the prediction of one makes it impossible to predict the other. That is, when one property is predicted by one operator, the mathematical operation changes the wavefunction and so the prediction made for the other property is not the same as it would have been if the second property had been predicted first. Since the order in which the operators are applied to the wavefunction makes a difference in what they predict, it is impossible to predict both properties at once. Thus, the conjugate variables to which Heisenberg’s uncertainty applies turn out to be the pairs of properties predicted by non-commutable operators.

When the operator yields an expectation value that is just the average result for an entire series of experiments, it can often be represented as a superposition of different wavefunctions for each of which the operator gives an expectation value. When the measurement is made and one of them turns out to be true, the wavefunction is said to “collapse,” because the system turns out to have one or another of precise predicted outcomes. This is called the “collapse of the wavefunction,” because it is assumed that prior to the measurement, what actually existed was a superposition of different wavefunctions.

This interpretation of the measurement of a quantum system exacerbates the problem, for the superposed states of the system can evolve in radically different ways. In the most famous example, a cat is locked in a box with a devise triggered by an unpredictable beta decay that will, with 50% probability, release a poison that kills the cat within a certain period of time. But until someone looks to see what has happened, there is a superposition of the two states, one with a dead cat and another with a living cat, and reality only resolves itself into one or the other possibility at the moment someone looks. This implausible implication of measurement being the collapse of the wavefunction is called the problem of "Schrödinger’s cat."

The Heisenberg uncertainty principle is, perhaps, the most general statement of the puzzles of quantum mechanics, and a genuine ontological explanation of quantum mechanics, if there is one, should reveal the source of this limitation on our knowledge.

Bell correlations. Recently, attention has focused on a final quantum mystery, called “Bell’s Theorem” or “Bell’s Inequality.”xlvi John Bell showed that quantum mechanics entails, in certain circumstances, a statistical correlation between events occurring at a distance that seems to be possible only if the events have effects on one another that travel faster than the velocity of light. It holds for interactions in which particles move away from one another in opposite directions with opposite orientations of a “spin”.

Spin. Spin is a quantum property that was first recognized with the discovery of quantum field theory. The Schrödinger wavefunction is the law of non-relativistic quantum mechanics, and a more complete law was discovered by Paul Dirac when he combined the Schrödinger wavefunction with Einstein’s special theory of relativity, that is, taking the relationship it describes between space and time into account.

There was an asymmetry between the time-dependent and time–independent wavefunctions derived by solving Schrödinger equation. The time-independent wavefunction, describing the spatial aspects of the standing wave, is a second order differential equation, whereas the time-dependent wavefunction, describing how the quantum system unfolds in time, is a first order differential equation. Dirac derived a time-dependent wavefunction that was a second order differential equation, making time and space symmetrical, as they are in the special theory of relativity.

It is puzzling just what makes Dirac's derivation work, but it involved several profound discoveries.

Dirac discovered that there are twice as many solutions for the wavefunctions than had been thought, half of them corresponding to negative energy. This was the discovery of antimatter, such as, for example, the positively charged electron as the negative partner of the negatively charged electron, called the "positron."

Dirac discovered that quantum particles have another property, called “spin,” which was a new quantum number that was needed for wavefunctions to describe fully any quantum situation. That is, spin is a new quantum number (namely, s) needed to describe the atom (along with Bohr’s numbers for the energy states of atoms (n), a number for the orbital angular momentum of the electron (i), and a number for its magnetic moment (m)).

It is believed that the intrinsic spin of an electron has little to do with a spinning electrical charge. The spin of a particle is defined operationally as the strength of the magnetic force that results when a magnetic field is imposed on the particle. Particles, such as the electron, that have ½ spin (called “fermions”) have one of only two possible magnetic moments (positive and negative). Since there is no way for them not to have a magnetic moment, it is hard to see how they could be a classical material object with a charge that is somehow actually spinning.

Bell’s Inequality. John Bell discovered a curious consequence of quantum mechanics involving spin. The spin of a particle (either a rest mass or a photon, which has a spin of 1) would seem to a property that the particle carries with it, but a prediction made on this assumption contradicts quantum mechanics. And it seems to have been disproved empirically. This suggest that spin is a property that depends, not on the particle itself, but on what happens elsewhere in a much more inclusive system involving both particles.

The system is one in which two objects are generated in a way that requires them to have opposite orientations of spin, and they move away from one another in opposite directions. Since space is three dimensional, the spin of a particle can be measured from three different, mutually perpendicular directions. If one particles is measured as having as having spin, say, up, in some direction, then the other particle will never turn out to have anything but the opposite, down, orientation of spin when it is measured in the same direction. This holds regardless which of the three independent directions in space the magnetic field is oriented, and quantum mechanics does not permit one to infer from its spin in one direction what its spin in any other direction is. Thus, if spin is a property that the particles already have when they part from one another, the outcome of measuring the spin of the particles that moved off one way from their creation from one direction should not enable us to predict the spin of the other particle when measured from a different direction. Bell showed that, on this assumption, a certain inequality must hold about the frequency with which measurements of spin in one particle in one direction would correlate with measurements of the spin of the other particle in one of the other directions.

However, quantum theory predicts and experiments have confirmed that this inequality will be violated. When two objects are generated in this way, and the spin orientation of one of these objects is measured in one direction, it is possible to predict the outcome of a measurement of the spin orientation (up or down) of the other object in an independent direction of three dimensional space more often than the Bell inequality allows. It is not a reliable prediction in any particular case, but statistically it is more frequent than would be possible, if the spin orientations of both objects were already determined when they parted and they were simply carried away with them, as the principle of local action would require.

Though the two measurements can be made as far apart in space as one likes, it seems that the only way the measurements could be correlated is if the measurement of one object were somehow affecting the state of the other. And since the two measurements can be made to occur as near to one another in time as one likes, there are instances of this phenomenon in which such an effect could hold only if something travels between them faster than the velocity of light. This puzzling correlation is not only a consequence of quantum theory, but has also been confirmed experimentally, and thus, it seems that we must give up the principle of local action. But it seems to violate the principle of local action. Since the different outcomes are a superposition of different wavefunctions, this is seen as just another puzzles about the so-called "collapse of the wavefunction."

The puzzles of quantum mechanics have to do with understanding what in the world corresponds to the Schrödinger equation. The “Copenhagen interpretation” of quantum mechanics, developed by Bohr, is the received view. It simply denies that it is possible to describe the nature of what exists except by applying the classical conceptions of particles or wave, which if not strictly speaking incompatible, are, at best, complementary. Defenders of the Copenhagen interpretation see the puzzles of quantum mechanics as deriving from its departures from classical physics, as if classical physics were based on intuitions ( or a form of imagination) that is anthropocentric and, thus, merely subjective. And some go on to insist that the uncertainty is a real indeterminism about what happens in the world.

The chief opponent of this view was Einstein. He was resisting the reification of quantum uncertainty as indeterminism when he claimed, “God does not play dice with the universe.” A view of the world as being constituted by substances of some kind is what kept Einstein from accepting quantum mechanics as the complete description of what exists. His acceptance of spacetime as a substance made him most sympathetic to Spinoza, for Spinoza believed that the world is a single substance. But what seems to have kept Einstein from admitting that such a substance could have indeterminism as a basic property were his ontological instincts.

In what follows, I will elaborate the the assumptions of spatiomaterialism in a way that explains ontologically why quantum mechanics is true. It is, as I have warned, more speculative than the rest of the argument of ontological philosophy. But it may suggest the power of an ontological approach and vindicate Einstein’s view of the nature of the world in at least one respect.

The theory of quantum matter. In order to show the possibility of a spatiomaterialist explanation of quantum mechanics, I will describe one way that the relevant phenomena might be constituted by space and matter as substances enduring through time. This will require a refinement of the assumptions made thus far about the natures of both matter and space. It is a refinement is a basic aspect, because it has to do with how these substances endure through time.

Space and matter were postulated in Spatiomaterialism as substances with essential natures that are opposite in a most fundamental way. The parts of space all have essential natures that include geometrical relationships to one another, so that the existence of one depends on the existence of all the others. But the parts of matter can all exist independently of one another. Being opposite in that way, it was possible to explain why bits of matter have spatial relations to one another and how change is possible by assuming that bits of matter exist together with space as a world by each coinciding with some part of space or another. These are the basic assumptions of spatiomaterialism, and it is possible to make further assumptions about the natures of space and matter, as long as they are consistent with these basic assumptions.

I made further assumptions about the nature of space and matter in order to explain how the laws of classical physics are true. I assumed that the nature of matter coincides with space in all the forms that are counted by physics in its principle of the conservation of mass and energy: rest mass, kinetic energy, two kinds of force-field matter (electric charges and gravitational fields), and two kinds of waves of forces (electromagnetic waves and gravitational waves).

I made another assumption about the nature of space and matter in order to explain Einstein’s special theory of relativity ontologically. I assumed that space has an inherent motion (or “ether”) which determines the velocity of light), and that material objects suffer Lorentz distortions as a function of their velocity relative to the inherent motion. (In order to suggest the inevitability of the Lorentz distortions, I anticipated a conclusion that I will defend here, namely, that material objects are constituted by unit-like interactions that are equivalent to the two-way electromagnetic interactions involved in the an interferometer.)

I made yet another assumption about the nature of space and matter in order to explain Einstein’s general theory of relativity. I assumed that centers of matter exert a force on the surrounding space that accelerates the inherent motion (or ether) and, thereby, accelerates all the bits of matter that coincide with space by way of it.

In order to explain ontologically the truth of the laws of quantum mechanics, I will make further assumptions about both space and matter.

Space. As we have already assumed, space has an inherent motion. This aspect of the nature of space determines the velocity of light. This assumption about the motion of electromagnetic waves (or photons) is crucial to the spatiomaterialist explanation of relativity theory, because it is the motion of objects with rest mass relative to the inherent motion that gives rise to the Lorentz distortions which explain the phenomena of special relativity. And the acceleration of the inherent motion itself relative to space is what explains the gravitational phenomena covered by general relativity.

The inherent motion of space is what plays the role that the ether was supposed to play in classical physics. The inherent motion mediates all the motion and interactions among bits of matter, because it is the aspect of space by which bits of matter coincide with parts of space. Since the inherent motion goes both ways in every direction of three dimensional space, there is a certain velocity at any point that is at “rest” relative to the inherent motion itself (that is, at rest in the ether). Relative to that inertial frame, light has the velocity, c, both ways in every direction in three dimensional space. But rest relative to the inherent motion may not be rest relative to space, because in gravitational fields, the inherent motion (or ether) is in motion relative to space and even accelerating. That aspect of its nature can, however, be set aside for now, because the inherent motion in substantival space that is the relevant aspect in explaining the quantum nature of matter.

To make it concrete, consider what the inherent motion must involve in order to explain electromagnetic waves. It must exist at every location in space at every moment. It must always have the same velocity in space (except, of course, for the changes that occur in gravitational fields). In each part of space, it must sweep through space in every possible direction, that is, both ways in every direction in three dimensional space. And it must be able to carry electromagnetic waves of every possible wavelength and every possible phase of every wavelength across every point in space, preserving their wavelengths and phases. (And as we shall see, it must do this for photons of two kinds, one of each possible orientation of spin.)

Since the inherent motion is sweeping through every part of space at the same time, what is sweeping through any part of space in any given direction is like of a wave front. The same motion sweeps through all the points in every two dimensional plane of which it is part. Indeed, there is such a wave front sweeping in every direction through every point of space.

Nor is it inappropriate to speak of the inherent motion as having waves, since it carries every possible wavelength of light, and as we shall see, the wavelengths of those wave fronts make a difference in what happens. It takes a certain period time for a photon (a complete cycle of electromagnetic radiation) to pass any given point, and since the photon is carried along by the inherent motion, such a cycle marks out a certain distance (its wavelength) over and over along its path. Indeed, since this is always happening, there is always already a series of wavelengths implicitly marked out in space by the inherent motion at any given wavelength, each going through a cycle at the same time as all the others, that is, at the present moment. This pattern holds for every wavelength and for every phase of each wavelength both ways in every direction. And it holds both ways in every direction for each point in space.

I elaborate this implication of postulating the inherent motion in order to make explicit what all I will not try to explain about the nature of space. By calling it an “inherent motion in space”, I mean that it is an aspect of the nature of space itself. That means, at a minimum that it is occurring at every location in space, whether there is any light there or not. But what is more, it means that space is what causes light to move as it does. The inherent motion at any location in space carries light along with it, when matter of that kind happens to coincide with that part of space. Unless the inherent motion of space were responsible for the velocity of light, it would not be possible to explain relativistic phenomena ontologically.

The inherent motion, therefore, marks out distances in space according to any cycle of changes occurring locally as time passes. This is to talk about the inherent motion as if it were a real set of events taking place in space, and as I said earlier, it may be possible to formulate a simpler spatiomaterialist explanation in which the inherent motion is merely a spatio-temporal aspect of the nature of space as a substance, that is, a geometrical structure about space and time. The inherent motion is, after all, basically a relationship between distances in space and periods of time that are built into the essential nature of space. That is to add a temporal aspect to the spatial relationships that space was originally assumed to have in Spatiomaterialism in order to explain the three-dimensional geometrical structure of space.

Each part of space has not only an essential geometrical relationship to every other part of space at the present moment, but also an essential relationship to future and past moments in the existence of every other part of space. To be sure, the past and future states of parts of space do not exist, because nothing exists but what exists at present, if substance endure through time. That means that one location’s relationship to future or past states of another location is a temporally complex property of space, which determines the maximum velocity with which what happens in one part of space and affect what happen in other parts of space. But that temporally complex property corresponds to a temporally simple relationship that actually exists among the parts of space as time passes. That is what I mean to emphasize by talking about the wave patterns set up in space by the inherent motion sweeping though every part of space, both ways, in every direction. These patterns may be nothing more than simply how all the parts of space endures through time, but speaking of these patterns as being laid out by the inherent motion in real time dramatizes the role they play in explaining the regularities described by quantum mechanics. And at this point, clarity about what is being assumed is more important than simplicity, since it is not necessary to have the simplest ontological explanation in order to show that there is such an explanation.

Matter. In order to give a deeper explanation of the nature of matter, we must distinguish between two kinds of matter, which I will call “force-field matter” and “quantum matter.” Three of the six forms of matter that were distinguished in order to explain the truth of classical mechanics are forms of force-field matter (electric fields, gravitational fields, and gravitational waves), and three are forms of quantum matter (rest mass matter, kinetic energy matter, and photons). Force-field matter has already been explained ontologically as involving a property (or temporally variable condition) of parts of space (though there is more to be said about it). And it is the nature of quantum matter that will bear the major burden of this ontological explanation of the quantum mechanics.

Force-field matter. By “force-field matter,” I mean forms of matter that are constituted by a changeable property or condition of parts of space. The property of space acts like a force, because it changes the way in which bits of matter coinciding with that part of space move and interact. Consider the three forms of force-field matter:

Gravitational fields. Gravitational matter is one kind of force-field matter, and we can set it aside, because it has already been explained. Gravitational matter is the matter that exists as the force field that gravitating bodies impose on the surrounding space, accelerating the inherent motion (the ether) toward themselves. Like any form of potential energy, the quantity of matter involved in a gravitational field is already counted in the rest masses of the objects exerting the forces. That is, their rest masses decline as the bodies attract one another, acquiring kinetic energy at the expense of potential energy (though as we shall see, force-field matter is not actually converted to kinetic quantum matter until the material objects acquire kinetic energy relative to the inherent motion by colliding with other material objects near the center).

Gravitational waves. Since gravitation is a force that propagates with the inherent motion of space, gravitating bodies can set up gravitational waves, which exist independently of material objects with rest mass, for example, from binary stars, which are in orbit around one another. But this is still a form of force-field matter, not quantum matter, because the gravitational force propagating at the velocity of light acts on space, not on bits of matter directly. It is by accelerating the inherent motion in the parts of space it encounters that gravitation accelerates bits of matter, not by interacting with bits of matter directly.

Electric fields. An electric charge also imposes a force field on the space surrounding the material objects that has the charge, and that is another form of force-field matter. The electric field is another property (or variable condition) of space which affects other material objects with electric charges. Electromagnetic matter contained in electric charges is already counted in the rest masses of the objects that have the charge, and matter is conserved, because as we have seen, the consumption of potential energy is counted as a negative quantity.

The electric field is more complex than the gravitational field, as we have seen, because changes in the electric field cause magnetic forces. But that connection between electric and magnetic forces, which is described by Maxwell’s equations, can be explained as another aspect of the nature of space. That is, changes in the electric field caused by the motion of an object with rest mass propagate as a result of the inherent motion in space, and thus, the electromagnetic interactions are relative to the inherent motion (as we have assumed in explaining Einsteinian relativity).

Quantum electrodynamics is the gauge field theory that is currently accepted by physics as an explanation of the electric charge and its behavior, and such a theory lends itself to a spatiomaterialist ontological explanation, because it portrays forces as being exerted by the exchange of particles, called the "boson" of the gauge field. In this case, it is a virtual photon. The electric charge is described as having a certain orientation in a complex vector plane, and the forces exerted on the charged particle by the virtual photons are just what is required for the orientation of the charge to be unchanged in that complex vector plane by its change of location. Those forces turn out to the forces described by Maxwell’s law. But since the force field is explained as virtual photons emerging from space as a result of the charged particle's motion at its location in the field, the gauge field theory is the kind of explanation that can be given an ontological explanation by spatiomaterialism. (More will be said about the nature of the electric charge and the gauge bosons that mediate interactions among charged particles as required as we go along and, more completely, when we take up the basic particles. See Change: Basic Objects.)

Quantum matter.The nature of quantum matter is the basis of this ontological explanation of quantum mechanics, and the remaining three forms of matter (rest mass matter, kinetic energy matter, and electromagnetic waves) are all forms of quantum matter. Like the new assumption about the nature of space, this new assumption about quantum matter recognizes a temporal aspect to the nature of matter, though it is a temporal property suited to the opposite nature of matter.

Parts of space are all connected geometrically, and since the inherent motion connects them all temporally as well, the endurance of space through time is characterized by the inherent motion (or the spatio-temporal geometry) described above. Much the same way of enduring through time also characterizes force-field matter, since force-field matter is spread out continuously in regions of space through which the inherent motion is constantly flowing. But since bits of matter can exist independently of one another, there is another way in which they can have a further temporal aspect to their nature.

The new assumption is that quantum matter is just a series of cyclic events that occur over time. That is, bits of quantum matter endure through time as a series of unit-like events whose cyclic nature entails that each event gives rise to another event of the same kind (unless it interacts with another bit of matter in some way and another kind of cyclic event ensues). Since these events follow one another as time passes, cycles of events (of the same kind) are a way of counting time, much as the inherent motion in space allows periods of time to be counted by the distance it crosses. These events will be called “quantum event,” because these are the smallest changes that can take place in a spatiomaterialism world (except for the inherent motion itself in smaller parts of space). Quantum events cannot be divided up in to smaller events, and so they are elementary units. But since they are cyclic events, each gives rise to another event, and since they reproduce in time, they explain the endurance of bits of (quantum) matter through time. The way that matter endures through time as a series of cyclic quantum events is mainly what the “quantum” in quantum mechanics is referring to, according to this spatiomaterialist explanation of quantum mechanics.

An “event” has both a spatial and a temporal dimension. It begins at some place and time and ends at some place and time. What happens in a quantum event is that a force is exerted and change is caused. The force may cause a change in another force, as illustrated by the photon, in which electric and magnetic forces are coupled in cycles. Or the quantum event may be a force that changes the motion of an object with rest mass, as we shall see holds in the case of the motion of an object with rest mass.. Different forms of quantum matter are constituted by different kinds of quantum events, as we shall see. But since they are elemental events, they all have the same, smallest size. That size is what is represented by “Planck’s constant”, h.

Planck’s constant is a certain size in a parameter called “action”. Though action was recognized early in the Newtonian era as one kind of physical quantity, it has nearly dropped out of contemporary physics (except for the constant h), apparently because it need not be mentioned in describing efficient causes. Action is, however, defined in terms of a certain physical quantities that are mentioned as efficient causes (such as spatial relations, mass, force, velocity, acceleration, momentum, and energy). For our purposes, the most useful way to think of action is as the product of force times distance times time, as if a force were acting on something (such as a unit mass) for a certain distance over a certain period of time.

In units that physicists take to be basic, action has the dimensions of mass times distance squared per unit time (or mass times distance squared per unit of time squared, all times time). And in addition to thinking of it as force times distance times time, it can be seen as momentum (or mass times velocity) times distance (that is, as the integration of a change in momentum over the distance it occurs). Alternatively, it can be seen as energy (mass times velocity squared) times time (that is, as the integration of a change in energy over the period of time it occurs).

In speaking of momentum and kinetic energy, I assume that we are talking about matter that is nearly at rest in the ether, where Newtonian laws hold and momentum is approximately equal to mass times velocity and kinetic energy is approximately equal to one-half of mass time the square of velocity. This is not quite true, because according to the special theory of relativity, mass increases with velocity. However, by starting with rest mass as the quantity of matter constituting particles at rest in the inherent motion, it will be possible to explain why mass increases with velocity, because we will be able to explain the extra mass as the matter making up its kinetic energy.

The idea is, therefore, to interpret the quantum of action as an event, that is, as a change of some kind that takes place in the world as a result of something being done. This may be a little vague, but remember that we are taking now about the most basic elements of what exists in the world, and the nature of quantum events can be made clear only by considering their various kinds. But since action is measured in units that include both space and time, it is possible to think of these events as having determinate boundaries in space and time, that is, as beginning at some place and time and ending at some place and time. That gives these events determinate locations in the geometry of space and time as determined by the velocity of light, that is, by the inherent motion.

Planck’s constant is a certain size of action, and we can explain why it appears in all the equations of quantum theory, if we assume that quantum events have an all-or-nothing character about them. Bits of quantum matter endure, we assume, because they are constituted by quantum events with a cyclic nature. Although cycles of quantum events may follow one another continuously in time and space, there is a unit-like nature about them, so that either a whole quantum event occurs, or it does not occur at all. This means, on the one hand, that nothing can happen that involves less than a unit of action (except possibly the inherent motion), and on the other, that everything that does happen to quantum matter is made up in some way of a certain number and kinds of these elemental units of action.

The assumption that quanta all have the same amount of action is not as restricting as it may seem, because quanta have widely varied temporal and spatial dimensions. They can take place in a short distance in a brief period of time, if the force is great enough, or they can take place over a longer distance in a longer period of time, when the force is weaker. But in order to spell out the assumption that they have a unit-like nature, let us think of quanta as having end points in space and time, so that quantum events can be fit together as complete cycles in the spatio-temporal geometry of the inherent motion of space in different ways. This model may be too crude. It is unlikely that quantum events have anything as abrupt as definite points at which one cycle ends and another begins. But that is a way of keeping in mind the unit-like nature of these events, even if it is just a place-holder to be replaced by a better explanation of where and how one quantum event ends and another quantum event begin.

For example, a better model of their unit-like nature would, perhaps, be one in which interactions between different bits of matter can occur only when whole cycles of the different bits of matter are lined up somehow according to the spatio-temporal geometry of the inherent motion in space. That is, given their precise locations in space and time, the points at which quantum cycles stop and start would depend on what they are interacting with and the direction from which they are interacting, so that different starting points and stopping points might hold if they were interacting with quantum cycles of bits of matter from different directions in space, of different kinds, or with different phases to their cycles. (Lining particles up in this way could be, as we shall see, the role of their intrinsic spin and its magnetic moment in mediating interactions of bits of quantum matter.)

Matter is a substance, because it exists continuously over time, never coming into existence nor going out of existence. We are assuming that one form of matter can be converted into another, including conversions between quantum matter and force-field matter (that is, between potential and kinetic energy). But when matter exists in the form of quantum matter, the endurance of bits of matter through time is explained by the cyclic nature of the quantum events that constitute their existence. That is, given that the quantum event starts at some place and time, there is a certain place and time where the cycle is complete, and at that point, another quantum event begins. Since quantum events are related cyclically, they can reproduce themselves in time. However, quantum cycles succeed one another not only temporally, but also spatially, so that nothing is flitting about discontinuously from place to place in space. Other things being equal, quantum events give rise to other quantum events of the same kind and dimensions as themselves.

Bits of matter do, however, interact. I will say more about how they interact in a moment, but in general, what happens is either the conversion of matter between quantum forms and force-field forms of matter and/or changes in the kinds of quantum matter. Force-field matter is laid out in space, changing its shape with the motion of the material objects that are imposing the forces. And since material objects, their motion and photons are just cycles of quantum events reproducing themselves in time, what changes are the kinds, numbers, and dimensions of the quantum events constituting them.

Since the quantum events have a unit like nature, what happens to bits of quantum and force-field matter in space involves fitting quantum events together in space and time according to certain laws as if the endurance of the world through time were the result of building a brick wall into the future. Some bricks are simply stacked on top of one another, as quantum cycles reproduce themselves in time. But when bits of matter interact, the bricks fit together in more complex ways, changing the sizes and locations of the bricks in the next row. The space on which the wall is being built also plays a role, because the sizes of the brick may also change with their locations (as in force fields), and the effects of space on their sizes changes with the locations of the bricks affecting space (as in changing location in a force field). Nature is a master mason, never failing to lay in the next layer of bricks according to fixed rules, and thus, there are regularities about change as the brick wall is built into the future. And the structures formed by them can be quite stable over time.

In order to spell out the details of these “rules of quantum masonry,” I will describe each of the forms of quantum matter and then take up the issue about how they interact with one another. Some of the quantum puzzles will be explained along the way, and in the end will, we will see how their interactions explain the structure of the atom, the Heisenberg uncertainty principle, and the Bell correlations.

To explain the endurance of matter by the cyclic nature of quantum events may, however, make it seem that matter is not a substance at all. If quantum events are ultimately just the exertion of a force in some part of space making some other event occur that is also constituted by forces, it is conceivable that quantum matter is just a property of parts of space, much like force-field matter. Could matter be entirely reducible to space? This is not what we assumed when we took spatiomaterialism as the foundation for this ontological way of doing philosophy.

The reduction of matter to space is, however, something that ontologists should welcome, if it is possible, for it would be just as complete as spatiomaterialism, but a simpler, and, thus, better ontological explanation of the natural world. It is more or less what Einstein was trying to do during the latter part of his life in attempting to construct a unified field theory. He wanted to describe matter another kind of curvature of spacetime, along with gravitation. If something like that comes of this ontological explanation, then spatiomaterialism will turn into spatialism.

However, I will put this possibility aside. In the first place, we would be getting ahead of ourselves to assume at this point that spatialism is true. We have yet to see how matter can be explained by cycles of quantum events. And second, even if an ontological explanation of quantum mechanics like this stands up in the end, it does not seem to me that that would make spatialism true. You may be able to reduce the inherent motion in space to spatio-temporal geometry, but the unit-like nature of quantum events will keep them from being reducible to properties in space. Each quantum event occurs over a period of time, and since quantum events cannot exist unless the whole event occurs, to postulate their existence is tantamount to holding that what exists includes entities with a temporal dimension to their essential nature. Bits of matter-time may be less problematic than spacetime, but in a world in which nothing exists but the present moment, they are, strictly speaking, not possible. Thus, this unit-like nature can be explained only by postulating the existence of a substance with a part-whole relationship of some kind that make it appear to be made up indivisible cycles of events. Whatever its nature, it basically different from the essential nature from space. Space is incapable of explaining the unit-like nature of quantum events, because it must exist only at the present moment in order to have an inherent motion that flows continuously. The only plausible way of explaining the all-or-nothing character of quantum events is to postulate another kind of basic substance, distinct from space, which can coincide with parts of space, for in that case, we can believe that, despite seeming to have a temporal dimension to their nature, quantum events also exist only at the present moment. There is, however, no need to settle this issue now.

Forms of quantum matter. I will focus first on the nature of quantum matter, since force-field matter depends on the existence of the bits of quantum matter constituting a particle with rest mass in nearby parts of space and it is fairly clear how it can be explained. Quantum matter includes electromagnetic waves, material objects with rest mass, and their kinetic energy.

The total matter is ultimately equal to the total quantum matter. Force-field matter is already counted in the masses of the objects exerting the forces, and gravitational waves eventually die out as they are converted into other forms of matter.

The quantity of quantum matter in any region of space is measured by the number of quantum events per unit time, for that is equal to the quantity of energy, given the definition of “action.” Since we will assume that all quantum matter is constituted by quantum events, the equivalence of energy and mass by Einstein’s equation, E = mc2, implies that each unit of mass must be equivalent to a certain number of quantum events per second.

The quantity of force-field matter involved in constituting the electric charge can be measured as potential energy, that is, in terms of the number of quantum events per second that can be converted from it, and that quantity must be subtracted from the total quantum cycles constituting rest mass.

After describing the nature of each form of quantum matter, I will take up the nature of electromagnetic interactions, bringing force-field matter back into the picture. But along the way, I will point out how this theory explains the peculiar nature of matter at the scale of the quantum and solves certain quantum puzzles.

Light. Light is the easiest form of matter to explain on the assumption that “quantum” refers to elementary events with the size indicated by Planck’s constant, for light can be explained as being made up of photons, each of which is the size of a quantum.

Light was understood as a wave in classical physics. According to Maxwell’s equations for electromagnetism, the change in the electric force has as its effect a magnetic force, and the change in the magnetic force has as its effect an electric force. Thus, the two forces interact, and their interaction can couple them in cycles of changing electric and magnetic forces that propagate through space at a fixed velocity, the velocity of light. Its wave-like nature is apparent in such phenomena as diffraction and interference.

As we assumed in explaining Einsteinian relativity, the velocity of light is explained ontologically by the velocity of the motion inherent in space itself. Let us, therefore, think of the electric and magnetic forces involved in electromagnetic waves as being carried along with the inherent motion in some direction. That will allow us to explain electric and magnetic forces as properties of parts of space, except for the way that they are coupled together in units as photons (or rather aspects of the inherent motion in space).

The particle-like nature of light waves can be explained on the assumption that each cycle of electric and magnetic forces is a single quantum event that occurs as a whole, if it occurs at all. Since these quantum events are cyclic, when one event does occur, it is followed, other things being equal, by another quantum event of the same kind. But since these quantum events coincide with space by way of the inherent motion, the next cycle of electric and magnetic forces occupies the next part of space in its direction. As the cycles reproduce themselves in time, therefore, they move across space, constituting an electromagnetic wave in time and space.

This ontological explanation of light accounts for the quantum equations used to describe the energy and momentum of photons. Energy is proportional to the number of quantum cycles per unit time, and that is what the equation for the photon’s energy says: E = hf (where f is the frequency of the light). The shorter the period of each quantum cycle, the more units of action that can occur in a unit of time, and thus, the more energy it carries.

The momentum of the photon can be explained in a parallel way, except relative to the direction of space in which the photon is moving. The dimensions of the quantum as a unit of action implies that the momentum of a quantum cycle is proportional to the number of quantum cycles per unit distance (in the direction of motion), and that is what the equation for the momentum of the photon says: p = h/l, where l is the wavelength of the light and 1/l is the number of cycles per unit length). In other words, the momentum is inversely proportional to the wavelength. Photons with shorter wavelengths have more momentum.

Since the velocity of light is constant, fl = c (where c is the velocity of light), and thus, the energy and momentum of the photon are proportional to one another: E = pc. In other words, the shorter the photon’s quantum cycle in time and space, the higher its energy and momentum, respectively. But since it is still the size of a quantum, the decreased size of the event in space and time means that the forces involved in each cycle are greater (since action is the product of force, space and time).

Since each cycle of electric and magnetic forces is a quantum event, no part of it can exist unless the whole cycle does. This unit-like nature to the events that constitute the existence of a photon is explained ontologically by how bits of matter coincide with space, and so it depend as much on the nature of space as it does not the nature of matter. (More precisely, the energy of the photon depends on the bit of matter apart from space, whereas its momentum also depends on space, because momentum is a result of the interaction of electric and magnetic forces being carried along by the inherent motion.) This suggests a straightforward ontological explanation of the phenomena that led to the recognition that light is made up of particle-like units.

Planck. What Planck discovered about blackbody radiation can be explained ontologically as a discovery about how photons coincide with the same part of space. What he discovered is that photons of different frequencies can all coincide with the same part of space as long as there their frequencies differ from one another by at least one quantum of action per second. This limitation on the frequencies that can exist in the same part of space avoids the so-called ultraviolet catastrophe, that is, why the total energy of photons at higher frequencies does not become infinite.

On this ontological explanation, what coincides with space are not just the changing electric and magnetic forces of electromagnetic waves, but rather complete cycles of such forces. And since the inherent motion contains each quantum of action is part of a wave pattern of a certain size that extends though the space in its direction, this limitation is a minimum difference that holds for the sizes of the wave patterns that can exist in that region of space.

Though this is a limitation on the variety of possible photons that can coincide with any part of space, the inherent motion in space is still handling a lot of different kinds of photons. In addition to all the frequencies of light in any direction that can exist at any part of space, photons of each frequency can have different phases (that is, different points in space where the cycle begins) as well different orientations of spin. Not only must the inherent motion be able to carry photons of all these kinds at once in any given direction, but it must also be able to carry the complete variety of photons in every direction in three-dimensional space. Indeed, at any given location it must be able to carry photons of all kinds both ways in every direction, and it must do so at every location in the region of space all the time. That is just how the parts of space are connected (though the inherent motion itself may be moving across space and being accelerated in a gravitational field).

Einstein. Einstein’s explanation of the photoelectric effect was that in order for light to free electrons from matter, the light had to have a high enough frequency, because the electron had to receive all the energy it needed to overcome the force binding it to the atom from a single photon. Lots of low frequency photons would not work.

This particle-like behavior of light is just what would be expected, if light is constituted by cycles of quantum events, because in order for light to interact at all, a whole quantum event of one kind must become a quantum event of another kind, in this case, it is the kind of quantum event that constitutes kinetic energy. And a single photon can supply the force needed to accelerate the electron, because photons with a higher frequency have smaller temporal and spatial dimensions and, given that each photon is a quantum of action, the forces constituting them must be correspondingly greater.

Compton. When a photon does interact, it is the whole photon that interacts. When a photon is scattered by an electron, for example, a whole photon is absorbed and a whole new photon is generated (one that is 180o out of phase with the original). The Compton effect has a straightforward ontological explanation, because the scattering of the high energy photon by an electron, like an elastic collision between two material objects, conserves both energy and momentum. The mass of the electron limits how much energy and momentum can be carried away, and that can be confirmed by measuring the direction and wavelength of the reflected photon.

Rest mass.Material objects with rest mass are another form of matter that was recognized in explaining the truth of classical physics, and our reason for thinking that rest mass is just another form of the substances that are counted in the principle of the conservation of energy was the equivalence of mass and energy (E = mc2) entailed by Einstein’s special theory of relativity. But having set aside force-field matter, we are now explaining those forms of matter as forms of quantum matter, and that requires us to hold that material objects with rest mass are constituted by quantum events in some way. And there is an obvious way to do so.

The rest mass of a particle can be explained as the number of cycles of quantum rest mass events per second, just as for the energy of photons. Such quantum cycles would, of course, have to coincide with space in a different way from photons, because objects with rest mass can remain at rest (or more precisely, have a constant velocity relative to the inherent motion in space). The simplest way to explain why such objects can be at rest is to hold that the quantum cycles constituting them go around in circles (or some such closed path), instead of moving across space with the inherent motion like photons. Moreover, since such quantum events would follow a closed path, like a circle, which brings the action back to where it began to start the next cycle, it is clear how quantum rest mass cycles can succeed one another in time.

In order to show that objects with rest mass can be explained as form of quantum matter, it will be necessary to show how all the basic particles recognized by physics can be explained by quantum rest mass cycles in this way. But that is a task that will not be taken up until the next chapter on contemporary physics, Cosmology: Basic Objects. For purposes of explaining quantum mechanics proper, we shall need only three kind of basic particles with rest mass: electrons, protons and neutrons. They are the near basic constituents of ordinary material objects of all kinds, and together with the electromagnetic force, including the photon, they can explain all the processes that occur in ordinary objects, from atoms to human beings. That is the range of phenomena covered by the quantum mechanics of electromagnetism.

Such ordinary phenomena do not include, of course, the sun, radioactivity, nuclear power and the like. These other phenomena depend on interactions among more basic particles than nucleons and their electromagnetic interactions with electrons. These more basic particles are recognized by physics, and they must all be explained as cycles of quantum events (and how quantum cycles coincide with space) in order for this ontological explanation of quantum matter to be complete. There is a way of doing that in which even the electron does not turn out to be basic, as explained in Cosmology: Basic Objects.

For the present, we shall simply take it for granted that electrons and nucleons can be explained ontologically as objects constituted by quantum rest mass cycles.

Visible light is made up of photons with frequencies of about 1015 cycles per second and energies about a few electron volts. Electrons have an energy of about one half million electron volts, and thus, the frequency of its quantum rest mass cycles must be on the order of 1021 cycles per second. And since protons have a rest mass about two thousand times that of electrons (or about 938 million electron volts), the frequency of their quantum rest mass cycles must be on the order of 1024 cycles per second. However, nucleons have a complex structure, and on this ontological explanation of them, their quantum rest mass cycles do not follow a circular pathway. It is a more complex pathway that may involve three or six quantum events to complete.

Electrons and protons carry an electric charge, as well as rest mass. The conservation of electric charge is explained by the gauge field theory for electromagnetism, and though what I will say about the electric charge is compatible with that theory, I will not try to explain it until we take up the basic particles. (See Change: Basic Objects: Gauge Field.) We shall just take the electric charge for grated.

Kinetic Energy.The assumption that kinetic energy is a form of matter was made in order to explain ontologically the basic laws of classical physics. We explained the principle of the conservation of mass and energy ontologically by the endurance of material substance, and that forced us to recognize that kinetic energy is a form of matter. What needs to be shown here is how kinetic energy matter can be explained as a form of quantum matter.

The received view is that the motion of a material object is nothing but its change of location in space over time. But that is not possible for an ontological explanation of the world that explains change by the endurance of substances through time, that is, as “real change,” because it must assume that nothing exists but what exists at the present moment. However, if nothing exists but the present moment, material objects are never in motion, and so wherein does its motion consist? To call motion “instantaneous velocity” is merely to name what needs to be explained.

Thus, ontology must recognize that the motion of objects with rest mass is not just their change of location over time, but rather is due to another form of matter that endures through time. That is, we must think of motion as an additional bit of matter that coincides with the material object and the part of space where the object is located. But it is a different form of matter, because it coincides with space in a way that moves the rest mass along in a certain direction at a certain rate.

This is to resurrect the notion that inertia is a kind of force that keeps the object with rest mass moving, and it explains, as we shall see, the difference between the rest mass of a material object and its inertial mass. But since heat is known to be the kinetic energy of material objects at the micro level, it is also, in effect, to vindicate the notion that heat is a caloric fluid, as we shall see in explaining Material global regularities.

De Broglie’s equation. Kinetic energy can be explained in terms of quantum cycles by supposing that there are quantum events that change the locations of material objects by a certain distance in a certain time. Newton’s first law of motion requires that material objects in motion continue in motion, and in order to explain why that law is true, we assumed that kinetic energy matter endures through time like any other form of material substance. But now we are explaining how quantum matter endures through time by the cyclic nature of quantum events, and so we must explain kinetic energy as a series of cyclic changes, each step of which can exist only as a whole. Let us call them “quantum kinetic cycles.” They will explain ontologically the truth of the de Broglie equations for the momentum and kinetic energy of particles with rest mass, which parallel the equations for photons.

De Broglie first proposed that particles with rest mass have a wave-like nature, much like photons. His equation, p = h/l, which was derived from the equation for photons, described the momentum of the particle as being inversely proportional to its wavelength, and that can be explained ontologically by the nature if the cyclic quantum events that constitute kinetic energy. The wavelength of the particle can be explained ontologically as the distance that the quantum kinetic cycle moves the particle during each kinetic cycle. And we can explain ontologically why the de Broglie equation is true, if we assume that for a unit mass, the length of the quantum kinetic cycle in the direction of its motion is inversely proportional to the momentum of the material object. Like photons, therefore, momentum is proportional to the number of quantum kinetic cycles that occur within a unit of space (in the direction of motion).

Just as the momentum is related to the spatial dimensions of the quantum events constituting kinetic energy matter, so the kinetic energy itself is related to their temporal dimension. The kinetic energy of the particle is inversely proportional to the period of its quantum kinetic cycle, so that its kinetic energy would be proportional to the number of cycles that occur in a unit of time, also like photons. In this case, E = hf, where f is the frequency of the kinetic cycle, or the inverse of its temporal size.

In sum, the faster the particle with rest mass moves, the shorter the distance covered by each quantum kinetic cycle, and the shorter the period required for each quantum kinetic cycle that moves it across space. But since each quantum kinetic cycle is a quantum of action, the shorter its temporal and spatial dimensions, the stronger the force that is acting to move the rest mass across space in each cycle, that is, the more inertia it has.

Quantitative relationship of momentum and kinetic energy. The cycles of quantum events that are responsible for the motion of objects with rest mass explain their momentum and energy, therefore, in much the same way as the momentum and energy of photons. But there is an important difference. In photons, there is a constant relationship between energy and momentum (described by the Einsteinian equation, E = pc), but no such relationship holds for particles with rest mass. Unlike photons, rest masses can have various velocities in any direction, and their momentum and kinetic energy do not have a constant relationship. On this ontological explanation, that means that the temporal and spatial dimensions of the quantum kinetic cycles by which the rest masses change location in space do not have a constant relationship.

From the equations for classical physics, we know that the momentum of a moving object is proportional to its velocity (p = mv), while the energy of its motion is proportional to the square of the velocity (E = ½mv2), and as promised when the laws of classical physics were being reduced to spatiomaterialism, this kinetic theory of matter explains why momentum and energy are related in this way.

To go faster, a particle with rest mass must have shorter quantum kinetic cycles in space, because their wavelength varies inversely with momentum. But with greater speed, therefore, quantum kinetic cycles carry the particle a shorter distance across space during each quantum event. In order for the velocity to be higher, the particle must cover more space in the same length of time, and that means that the period of each quantum kinetic cycle in time must decrease even faster than its length decreases in space. In fact, it is only possible if the period of the quantum kinetic cycle decreases in proportion to the square of velocity.

For example, if the velocity of a unit mass is doubled, the wavelength of each quantum kinetic cycle is cut in half. But that means that the period of each quantum kinetic cycle must be one-fourth as long as the previous quantum kinetic cycles, for otherwise the object will not travel twice as far in the same period of time.

Thus, the way kinetic quantum events must fit together in space over time in order to explain the motion of particles with rest mass explains why the kinetic energy increases with the square of the velocity, while momentum increases directly with velocity. It is a result of how the change in the spatial dimensions of quantum kinetic cycles must affect their temporal dimensions in order for momentum to be inversely proportional to their de Broglie wavelength. (And the reason that the kinetic energy of a particle is not equal to the frequency of its quantum kinetic cycles, but only half, is that only half that much energy is required to accelerate a particle to that “frequency.” More energy is required to accelerate objects at higher velocities, as we noted in explaining why the gravitational time dilation varies with altitude in a gravitational field, not with the strength of the force.)

Rest mass. This description of quantum kinetic cycles has assumed that the particle being moved has one unit of rest mass, but particles of different kinds have different masses and according to classical physics the mass of the particle helps determine its momentum. Its momentum is the product of its mass and velocity. For example, when two material objects have the same velocity, but one has twice the mass of the other, the one has twice the momentum and twice the kinetic energy of the other object. This can be explained ontologically on the assumption that the particle’s motion is due to quantum kinetic cycles, but it will require us to take into account the relationship between the quantum cycles making up the rest mass and the quantum cycle constituting its motion.

We are assuming that the rest mass of a particle is proportional to the frequency of the quantum cycles constituting its rest mass. In an object with twice the rest mass, there are twice as many quantum rest mass cycles per second. Though rest mass and kinetic energy are both a series of cycles of quantum events, and though the total matter is equal to the total of both kinds of quantum cycles per second, they are different forms of matter and each has an existence that is distinct from the other. But in order to explain the role of rest mass in determining momentum, we must assume that the quantum rest mass cycles determine a scaling factor for quantum kinetic cycles. For example, when two material objects have the same velocity, but one has twice as many quantum rest mass cycles as the other, the one must have quantum kinetic cycles whose wavelengths and periods that are half the other object.

This scaling factor would explain why the momentum and kinetic energy of particles is proportional to the rest mass. But it is only a scaling factor for the quantum kinetic cycles required to move the object across space. The period of its rest mass cycles are not changed by the motion of the particle with rest mass. Quantum kinetic cycles are additional quantum events whose size depends on how many rest mass cycles occur during each unit of time as well as how far the object is moved during each unit of time.

Inertial mass. This is only a first approximation to the explanation of how the size of the quantum kinetic cycles depend on mass as well as velocity, because kinetic energy is an additional quantity of matter that coincides with the object with rest mass and that kinetic matter must itself be moved along with the object with rest mass. Thus, since the total number of quantum cycles per second that is being moved along by the kinetic matter includes both the quantum rest mass cycles and the quantum kinetic cycles of the objects, the scaling factor for quantum kinetic cycles must depend not only on the total rest mass cycles but also on the total quantum kinetic cycles. Let us call that combined total quantum cycles the “inertial mass” of the material object, to distinguish it from the rest mass. And let as refine our ontological explanation of momentum and kinetic energy to make them proportional to the inertial mass of the material object, rather than its rest mass.

The rate for the conversion of matter between mass and energy is given by Einstein’s formula, E = mc2, and the simplest explanation is that it describes the rate at which additional quantum kinetic cycle contribute to the scaling factor. That fixes the number of quantum rest mass cycles for each unit of mass and constrains the explanation of rest mass by quantum cycles.

[However, the relationship may be more complex. It is possible that the quantum rest mass cycles constituting particles have a special nature (presumably because of how they depend on weakons and neutrinos and the unique structures that result), and each quantum rest mass cycle contribute more to total mass than a single quantum kinetic cycles. Let us proceed, however, on the simple assumption.]

[There is, however, no reason to doubt that the quantum kinetic cycles are simply added to the quantum rest mass cycles in determining the total mass (or energy, if you will) of the object. To be sure, the Einsteinian formula, E2 = p2c2 + mo2c4, suggests that the contributions of rest mass ( mo2c4) and the object’s motion (p2c2) to the total energy (E2) is more like orthogonal components of total energy as a vector sum. But this formula represents the object’s motion in terms of its momentum, that is, its spatial aspect, not its total energy. Energy is the temporal aspect of the quantum cycle, and both kinds of energy are included in this total. Furthermore, this equation merely describes the dynamic invariant that holds among inertial frames corresponding to the kinematic separation s (where s2 = c2t2 – x2, and the parallel is mo2c4 = E2 - p2c2). But on the spatiomaterialist explanation of special theory of relativity, the tradeoff between total energy and momentum (in the temporal and spatial dimensions) that makes inertial frames equivalent in this way is just an appearance. Not only rest mass, but also the total energy and momentum have absolute values, though they cannot be determined empirically, that is, measured.]

This ontological explanation of inertial mass would account for the Lorentz distortion in the masses of material objects with a high velocity relative to the ether, or what is called the “relativistic mass increase” (which was promised in Change: Special theory of relativity). The reason that inertial mass increases with velocity is that the total mass of the material object includes both its rest mass (the quantum cycles constituting its mass when it is at rest relative to the inherent motion) and the mass of its kinetic energy (the quantum kinetic cycles that give the object a velocity relative to the inherent motion).

Thus, not only is more energy required to accelerate a material object by a fixed amount at higher velocities relative to the ether because of the laws of classical physics (with higher velocity the force has to be applied over a longer distance in the same period of time to increase its velocity the same way), but more energy is required to accelerate a material objects by a fixed amount at very high velocities because of the relativistic mass increase entailed by Einstein’s special theory of relativity (with very high velocities, the mass of the kinetic energy that must be accelerated along with its rest mass becomes significant). As the material object approaches the velocity of light, the mass of the kinetic energy matter (and, thus, the inertial mass) becomes infinite.

Interference phenomenon. Finally, this explanation of kinetic energy as a form of quantum matter affords an explanation of interference phenomena (and diffraction) with material objects, that is, the phenomenon that most clearly demonstrates the wave-like nature of particles.

In order for quantum kinetic cycles to explain the wave-like nature of moving material objects, we must take into account the role of the inherent motion. Quantum kinetic cycles move objects with inertial mass relative to the inherent motion in space, but they are usually much slower than the motion that sweeps each point both ways in every direction. Let us assume, therefore, that as that motion sweeps through a material object in any direction, it picks up the wavelength of its quantum kinetic cycle and lays out, in the space beyond it, waves with the same wavelength (until it runs into another object). Since the wavelength varies inversely with the product of the inertial mass and velocity, the waves laid out in space by the inherent motion, in effect, broadcast information about the particle’s momentum and phase of its quantum kinetic cycle in every direction in the ether. (Since the inherent motion flows in all directions, waves are laid out in all directions indicating its momentum in each direction, including those opposite to the direction of the particle itself.)

In order to explain how the inherent motion picks up the wavelength of the quantum kinetic cycle, we must assume that it interacts with the quantum kinetic cycle as a whole. It is as if the inherent motion timed how long it took to pass through the whole kinetic cycle and laid down a mark in space each time the same period had passed again. But notice that this period is not the period of the quantum kinetic cycle itself. The material object takes much longer to cross the distance covered in a single quantum kinetic cycle than the motion inherent in space, and thus, the inherent motion will take many trips across the distance covered by each quantum kinetic cycle before it is succeeded by another quantum kinetic cycle. This effect on the inherent motion would not be possible, if the kinetic cycle did not have a quantum nature, existing as a whole or not at all, for it must interact with both ends of the path across which the material object is being moved during each cycle. In other words, the kinetic energy, which is inversely proportional to the period of the quantum kinetic cycle, is not broadcast to other regions of space by the motion inherent in space. Only the momentum is. And that is fitting, since momentum is the spatial aspect of quantum kinetic cycles, whereas energy is the temporal aspect.

In order to explain the interference phenomenon exhibited by objects with inertial mass in the two-slit experiment, we must recognize that the inherent motion sweeping through a material object in each direction, picking up the wavelength of its quantum kinetic cycle, is part of a wave front. When particles with a certain velocity are moving toward the barrier with two, closely spaced slits, some particles pass through, and their collisions with the wall lying beyond the barrier indicates that the two pathways are interfering with one another like waves. The particles collide with the distant wall only along certain fringes, and not between them. This would be just what is expected, if we assume that the particle tends to move along the path of waves that have been laid out by the inherent motion. The wave fronts broadcast by the particle are intercepted by the barrier except for the two slits. The inherent motion stops laying out wavelengths in space where it is intercepted by the barrier, but it continues laying them out where it flows through the slits. Thus, on the other side of the barrier, there are two wave fronts laying out the same wavelengths, one emanating from each slit, and they interfere with one another like light waves. Assuming that the particle tends to fall in step with the waves that have always already been laid out in the space between the barrier and the distance wall, therefore, its path is diverted away from paths on which the wave fronts interfere destructively toward those paths on which the wave fronts interfere constructively. That is, the particle always tends to be where its wave front is strongest.

If we use the crude picture of quantum cycles as having a definite starting point and ending point, we can think of the particle as being subjected to a force at the completion of each quantum kinetic cycle, if it finds itself in a position where the waves being laid out from the two slit are interfering destructively, which changes its direction slightly. But when it ends a quantum kinetic cycle where the waves from the two slits interfere constructively, it simply goes with the flow. Thus, the effect is to channel the particle along a certain path way. The actual path will vary from particle to particle with the same momentum depending on the direction its emerges from the slit it passes through, and so it results in a fringe of more and less likely points of interception by the distant wall.

In other words, in both photons and material objects, the cause of interference phenomena is the inherent motion. In the case of photons, the inherent motion carrying the relevant wavelength goes through both slits setting up a pattern of spacetime cells where they interfere constructively, and the direction of the photon is diverted slightly in those regions. It is the same in the case of particles with inertial mass, except that the relevant wavelength is due to the quantum kinetic cycles of the particle. In both cases, therefore, the interference phenomena also occurs when particles (photons or objects with rest mass) are sent through the slits one at a time. It depends on the geometry of the inherent motion moving in certain directions laying out a waves of a certain length in space. And in both cases, if one of the slits is blocked — or even if an apparatus is set up that can detect which slit a particle goes through — the interference effects disappear.

Schrödinger’s equation. The quantitative adequacy of the wave pattern laid out by the inherent motion to explain interference and similar quantum phenomena has already been demonstrated, in effect, by David Bohm (1993), for this role of the inherent motion is an ontological explanation of what he calls the “quantum potential.”

What happens in these experiments on particles with rest mass can be described by the Schrödinger wavefunction, and Bohm shows mathematically how such a wavefunction can be divided into a part that is due to the causally relevant factors described by classical physics and another part which he calls the “quantum potential.” The quantum potential is a rather strange force, because unlike classical forces, its strength does not decline with distance. The quantum force can be quite strong, but its casual role does not come from its strength, but rather from its spatial structure. Bohm describes the quantum potential as “active information,” for he assumes that the particle moves with its own energy and momentum, while the quantum potential merely informs it about how to do so in detail. The particle has a definite position and momentum at each moment, but its classically determined path is affected by the quantum potential that exists along with it. The Schrödinger wavefunction holds for all particles with the same momentum in the two-slit experiment, but the effect of the quantum potential on any particular particle cannot be predicted, because it depends on a so-called “hidden variable”.

The quantum potential is the key to Bohm’s explanation of how the Schrödinger wavefunction can be understood as referring to a fully deterministic process, and this ontological explanation of interference phenomena is an example of how spatiomaterialism would interpret what Bohm means by the quantum potential. The quantum potential describes the waves laid out in space by the inherent motion for any relevant wavelength of kinetic quantum cycles or photons. The effect of the waves laid out by the inherent motion makes the quantum potential look like “active information” (or a “pilot wave,” as de Broglie called it), because the particle follows the nearest path to its classically determined path in which the waves coming from various directions reinforce, avoiding those in which they cancel out. But to explain the quantum potential by the inherent motion is to disagree with Bohm on one point, for he holds that the quantum potential is simply a manifestation of a “nonlocality” about what happens that simply exists in the quantum system and does not depend on anything traveling across space over time. But on this ontological theory, it is due to the inherent motion.

Furthermore, the inherent motion explanation of the quantum potential makes it possible to hold that the hidden variable, which determines how any particular particle is affected by the quantum potential described by the wavefunction, is the particular phase of its quantum kinetic cycle. That is, any particular particle has a definite position and momentum at the beginning and end of its quantum kinetic cycle, and the Schrödinger wavefunction describes precisely what happens to it as a result of the quantum potential. But it is not possible to measure which phase any particular particle has, and since that wavefunction also describes what happens to all other possible particles with the same momentum (the complex numbers enable it to take all the different possible phases into account), the outcome can be predicted only probabilistically.

Solutions to quantum puzzles. The nature of the three forms of quantum matter has explained several quantum puzzles, and Bohm’s interpretation of the Schrödinger wavefunction points the way to a solution of those that remain. We have seen how both photons and particles with rest mass have both a wave-like and particle-like nature, though they are fundamentally different forms of matter on this explanation and have fundamentally different explanations. Photons are waves that have a particle-like nature because each such bit of matter is a complete cycle of quantum events, whereas particles with rest mass have a wave-like nature because their motion is constituted by another form of matter attached to the rest mass that endures through time as a series of cycles of quantum events. This points the way to a certain kind of ontological explanation of quantum mechanics, and in order to test its adequacy, let us consider how it would handle the three quantum puzzles: the structure of the atom, Heisenberg’s uncertainty principle, and the Bell correlations.

Structure of the atom. Bohm’s interpretation of the Schrödinger equation is the key an ontological explanation of the structure of that atom. Schrödinger’s equation determines a wavefunction for the conditions that hold in atoms, with a positively charged nucleus surrounded by electrons (but since it is too complex to solve when many electrons are involved, each electron is usually treated separately, taking the mean position of the other electrons as boundary conditions). The time-independent Schrödinger wavefunction for the atom has an amplitude for the electron that varies with locations in space, and as Max Born suggested, the square of that amplitude (when normalized) in any region of space can be interpreted as the probability of finding an electron located there. The wavefunction describes various orbitals, or regions of space relative to the nucleus where two electrons (with opposite orientations of spin) are most likely to be found. This is the structure that explains the periodic table of elements and is used to explain chemical bonds among atoms.

The orbitals of the atom are identified by quantum numbers, such as the principle quantum number (indicating the energy levels: n = 1, 2, 3 . .), the orbital angular momentum quantum number (l = 0, 1, 2, . . ), and the magnetic quantum number (m, which determines the orientation of the orbital angular momentum as a magnetic moment it has in a magnetic field imposed in some direction). Electrons also have an intrinsic spin quantum number, s = ½, and two electrons, with opposite orientations of spin can occupy each orbital. Here is a rough description of the possible orbitals.

Electrons occupy shells, corresponding to different energy levels, and in the lowest energy shell (n = 1), there is only one orbital (the s orbital), which can contain two electrons (with opposite intrinsic spin). It has no orbital angular momentum (l = 0). The probability of finding the electron in the s orbital is highest at the center of the nucleus, and the probability of finding it farther away falls off exponentially.

In the second shell (n = 2), with the next higher permitted energy, there is not only an s orbital, but also three different p orbitals. The p orbitals correspond to electrons having an orbital angular momentum (l = 1, as if they were in orbit around the nucleus), and each such orbital has a node running through the nucleus, indicating that a p electron will never be found to be located where the nucleus is. Moreover, in the plane in which it has its orbital angular momentum, the real (that is, non-complex) component of the wavefunction’s amplitude has the p electron located in one or another region on opposite sides of the nucleus, that is, 180o apart. Thus, since there are three p orbitals at the second energy level, atoms in which the second shell of electrons is full have (real valued) orbitals arranged in 3-D space that look like three, mutually perpendicular barbells.

In the third shell, at the next energy level, there is another s orbital, three p orbitals, and five d orbitals with a more complex geometrical structure, and so on through the energy levels of the atom. Since each orbital can contain two electrons (with opposite intrinsic spin orientations), the number of protons in the nucleus determines the structure of the lowest energy atom of each elemental kind.

In order to explain the structure of the atom ontologically, we need to recognize that it is constituted by three forms of matter and an interaction between them that can be seen as involving something in the nature of a photon (that is, virtual photons).

Rest mass matter. The particles with rest mass include the neutrons and protons that make up the nucleus as well as the electrons. But each proton and electron carries an electric charge, which is a form of force-field matter that helps constitute each particle, though as we have seen, the quantity of such matter is already counted in the rest masses of the particles.

Kinetic energy matter. Both the nucleus and the electrons are in motion as a result of their interaction, but the nucleus is so much more massive than the electrons that its quantum kinetic energy cycles are very small compared to those of electrons (and can be ignored in estimating quantities). Bohr assumed that electrons are in motion relative to the nucleus in order to explain the structure of the hydrogen atom, and despite doubts about electrons following determinate trajectories like classical material objects, it is clear that electrons have some kind of motion. (Electrons must move in order to have orbital angular momentum, and unless electrons in the s orbital had some kind of motion, there would be no explanation of how there could be s orbitals at higher energy levels.) Thus, according to this ontological explanation of the forms of matter, the electrons bound to the nucleus in an atom must have kinetic matter in addition to their rest mass matter, that is, the electrons are moved around by quantum kinetic cycles.

Force-field matter. Since protons and electrons carry opposite electric charges, they jointly impose a force field on the part of space occupied by the atom. The forces that these particles exert on one another change how they move, and the attraction of positive and negative charges is great enough to bind the electrons to the nucleus (with the negative potential energy representing the loss of some force-field matter that was counted in their rest masses as independent objects). But part of the force-field matter that the particles have given up still exists in the atom as the kinetic energy matter by which the electrons (and the nucleus) move across space as time passes, and the motion of electrons relative to the nucleus entails a change in the force field that is jointly imposed by them.

Virtual photons. The interaction between these particles is a process that is continually converting potential energy into kinetic energy and kinetic energy into potential energy, that is, converting matter between force-field matter and quantum kinetic cycles. Electrons (and the nucleus) are continually either giving up force-field matter and acquiring kinetic energy matter or giving up kinetic energy matter and acquiring force-field matter, and such transfers of matter are represented in the gauge field theory for electrodynamics as bosons, called "virtual photons."

The structure of the atom can be explained by the quantum nature of the kinetic energy matter of the particles with rest mass and the gauge bosons that transfer momentum and energy between them and force-field matter. Both the changes in the locations of the particles and the changes in the motion of the particles occur in a step like way, because they both involve quantum events. That can explain the structure of the atom, because those quantum events must fit together neatly in the spatio-temporal geometry determined by the inherent motion in space in order for them all to coincide with the same part of space. It is as if the quantum events constituting the atom were spatio-temporal bricks, and the existence of an atom were a result of their fitting together both spatially and temporally like a brick wall being built into the future. The masonry is so neat and well organized that the wall can be built indefinitely high, making the atom stable.

The quantum nature of kinetic energy matter means, as we are conceiving it in our possibly too crude way, that electrons (and nucleus) change location in a step-like way, that is, covering some whole distance in a period of time as a single, indivisible event. It is as if the electron must first complete an entire quantum kinetic cycle before it can change its momentum, and when it does change momentum, it must complete another complete quantum cycle before it can change again. Thus, only at certain locations and at certain moments does the electron change how it is moving.

Any changes that occur in an electron’s motion depends on the electric forces being exerted by all the electrons and protons, that is, on the field that they jointly constitute (because they are all made partly of force-field matter). These forces cause electrons to change how they move (that is, change their momentum), and that depends on some kind of (virtual) photon which gives the electron momentum and energy or takes it away. But on this model, such interactions occur only at the end of each quantum kinetic cycle, and it is a step-like change that determines the nature of the next quantum kinetic cycle. The quantum nature of the process makes the quantity of the change clear, because according to Newton’s laws of motion, the amount of energy and momentum that is transferred to the electron each time would depend on how much of energy and momentum the electron picked up from the force field matter in space during its previous quantum kinetic cycle. The change in the electron’s kinetic energy would depend on the distance it covered in the force field during the last kinetic event, and the change in the electron’s momentum (including its change of direction) would depend on the period spent being subject to the force field during the last quantum kinetic cycle. (Or more precisely, since the strength of the force varies over that distance and period, the change in energy would be the integral of the force over that distance, and the change in the electron’s momentum would be the integral of the force over that period of time).

This way of thinking about the quantum nature of the kinetic cycles may be an overly crude way of portraying the electromagnetic interactions, but the step-like changes bring out how the interaction involves not just the electron, but a complete quantum event making up its kinetic matter. The change occurs in a cyclic fashion, in which the last quantum kinetic cycle combines with the force-field matter to determine how much the next quantum kinetic cycle differs in momentum and energy. Such electromagnetic interactions are geometrically complex, because changes in electric forces cause changes in magnetic forces, which affect their motion, and what is more, these particles also have magnetic moments due to their intrinsic spin, which affects them in a different way. The way that these forces work is what is described by the gauge field theory for electrodynamics. The transfer of matter from force-field matter to kinetic matter or back is mediated by the gauge boson for the electromagnetic field, that is, by the exchange of a particle between them. This particle is like a real photon, because it is constituted by electric and magnetic forces interacting in some way. But it is unlike the photons that constitute light, because the momentum and energy it carries is not related by E = pc. They cannot have a constant proportion, because the energy and momentum needed to change the motion of objects with inertial mass as required by Newton’s laws do not have the same proportion in every case. (That is, momentum is a function of velocity, whereas energy is a function of the square of velocity, and so the proportion between them will vary with the velocity involved.) But this is just the nature of virtual photons, as opposed to real photons, which can exist independently and make up ordinary light. The matter constituting virtual photons can come from the force-field matter included in the rest masses of the particles, but they must have whatever unit-like nature is required to transfer all of the momentum and energy picked up from the force-field matter during the last quantum kinetic cycle at the moment that cycle ends, whatever the real nature of this possibly crude representation may be.

[When electrons do finally exchange a photon with the nucleus and their next quantum kinetic cycle is changed, they have a different location from where they were at the end of the last quantum kinetic cycle and their motion is changed for the next quantum kinetic cycle. This step-like change in their motion is the effect of virtual photons on the electron, but since the electron is a charged particles, it is also helping to impose the force field from which the virtual photons arises. And that is something that we must assume the electron does constantly, not just at the end of each quantum kinetic cycle, for as we shall see when we take up the gauge field theory, the electric charge is explained ontologically as a pulsation of electric forces emanating from the center of rest mass that is synchronized with electric charges throughout the universe. That is, all negative electric charges exert their maximum electric force at the same time in a cyclic way, and what makes positive electric charges opposite is that they exert their maximum electric force 1800 out of phase. (The synchronization of their pulsations is what is represented by their "orientation in complex vector fields," and the virtual photons of the gauge filed theory are the forces that must be exerted on charged particles as a result of their motion in order to conserve electric charge, that is, to keep their pulsations in synch with the universal pulsation of electric charges everywhere despite their motion.) In any case, in order to be able to explain quantum electrodynamics in this way, we will assume that electron is exerting its electric force in synch with the universal pulsation, and thus, it must occurs constantly during each quantum kinetic cycle. And that means that we are assuming that the electron has a determinate location at each moment during each quantum kinetic cycle. (For furthere discussion, see Change: Basic Objects: Gauge Field.)]

If the interactions among these forms of matter must have the unit-like nature that we are assuming explains Planck’s constant ontologically, the structure of the atom can be explained as a result of how all the kinds of quantum events involved fit together in the spatio-temporal geometry determined by the inherent motion in the part of space where they exist. This means that the interactions between the electrons and the nucleus would have a cyclic character, and all the interactions between electrons and the nucleus (as well as between the electrons themselves) would give them quantum kinetic cycles that are synchronized and related spatially, so that they fit together neatly in space and time like spatio-temporal brick in the atom as a brick wall being built into the future. But since there are slightly different combinations of momentums (quantum kinetic cycles) and positions (the locations where one quantum kinetic cycle ends and another begins), there is no way to say precisely where any particular electron is at any time.

Without trying to explain the orbitals in detail, it is clearly possible that the electrons are following determinate pathways as a result of interactions of this kind, changing their quantum kinetic cycles in a step-like way while all the time helping constitute the electromagnetic force field by way of their (pulsating) electric charges.

Though electrons in the s orbital are most likely to be found in the nucleus, that does not mean that they do not have a regular motion at all. Assume that each such electron is in a cyclic interaction with the nucleus in which it is accelerated first in one direction across the nucleus and then back in the opposite direction. The changes in how it moves come at the end of each lap when it is maximally far away from the nucleus, and it does not change its velocity during the trip, because it is a single quantum kinetic cycle (at least in the lowest energy state). That is, where one quantum kinetic cycle ends and another one begins, the electron changes its momentum all at once, without slowing down or speeding up. The reason it is most likely to be found at the center of the nucleus is that it can have any direction of back and forth motion through the nucleus, and the nucleus is the one part of space traversed by every possible pathway. At higher energy levels, the electron would be moving faster, and thus, it would have quantum kinetic cycles that are shorter and quicker, and at the n=3 energy level, it means that the electron has a good chance of being located either with the nucleus or at a distance from it, but not in between.

Electrons in the p orbital at the n=2 higher energy level have an orbital angular momentum. But it may seem that they cannot have a circular orbit around the nucleus in the relevant plane, because its orbital is usually represented as being a sphere located mostly on opposite sides of the nucleus. But the regions on opposite sides of the nucleus are just the real component of the amplitude its Schrödinger wavefunction, and the complex component puts it on opposite sides of the nucleus in the same plane, except for being rotated by 900. The p orbital could, therefore, be a result of two quantum kinetic cycles, each trying to pull it back and forth across the nucleus in perpendicular directions (as in the s orbital), but perpendicular to one another. The quantum interactions with the nucleus that keeps changing their quantum kinetic cycles would have to be synchronized to occur 900 out of phase to have this result, but that could be just the condition of such quantum events being able to coincide with the same part of space at all.

Even though different p orbitals are rotating electrons in independent planes of three dimensional space, they may also be synchronized in a certain way so as to keep the electrons from exerting too great a repulsive force on one another. (The general synchronization of these quantum kinetic cycles and changes in them is evident in the s electron at the third energy level, for its probable location is either outside the lower level shell or at the nucleus, suggesting that it is continually moving through those shells in some way.)

The reason that two electrons can fit into each orbital is that, with opposite orientations of spin, they can be synchronized in exactly the same way, but 1800 out of phase or in the opposite directions. Their opposite orientations of their intrinsic spins would exert a force (a "magnetic moment") that lines them up in opposite ways in the magnetic field, and that suggests that the magnetic fields plays the central role in making it possible for the exchange of virtual photons to generate such a neat pattern in the spatio-temporal geometry of the inherent motion.

Much more needs to be worked out in order to show how all the electrons in the orbitals could be following determinate trajectories determined by quantum kinetic cycles, but there seems to be no reason to deny that they have such step-like trajectories, even if they cannot be measured precisely. And it could be extended to include the other orbitals of atoms and the molecular orbitals that explain chemical bonds among atoms and groups of atoms.

Quantum jumps. Finally, the puzzle about the electron jumps entailed by the step-like changes in the energy level of atoms would be solved. All the changes in momentums of electrons, even those within its energy level, are step-like jumps. They occur at the end of one quantum kinetic cycle (in our possibly crude way of thinking about it) and before the next quantum kinetic cycle begins. It is clear that the change in energy state is a change in the orbital occupied by an electron is a step-like change, because it occurs with the absorption and emission of a single photon of the appropriate energy (and momentum). But that is just what would be expected, if the atom has a structure that is determined by the way that the quantum events of the various forms of matter constituting the atom must fit together in order to coincide with the same part of space given the spatio-temporal geometry determined by the inherent motion in space. The electron absorbs or emits a real photon, which changes its next quantum kinetic cycle so that it is part of a different orbital. The only possible changes are step-like changes, because they are changes in the structure of the atom.

The structure I have tried to describe here is the same structure that is determined by the “quantum potential” that David Bohm found in the Schrödinger wavefunction by mathematically separating out the classical forces. That left a force with a localized effect that did not decline with distance in the way electric forces do, but spread throughout space. Though Bohm thinks of it as “active information” which tells the electron how to play out its classical role, it can be explained, as I have suggested here, by recognizing that kinetic energy exists as a form of quantum matter by which objects with rest mass coincide with space, because that determines the same structure in the inherent motion in space. Quantum kinetic cycles and the inherent motion in which they are fit together are, in other words, another ontological explanation of Bohm’s quantum potential.

Lorentz distortions. By the way, this explanation of the structure of the atom affords an of the inevitability of the Lorentz distortions. In explaining the truth of Einstein’s special theory of relativity, I showed that the Lorentz time dilation and length contraction would be inevitable in the atom, if the electrons were bound to its nucleus by a unit-like two-way electromagnetic interaction. (See Change: Special theory of relativity.) That is apparently the implication of the Schrödinger wavefunction that describes the motion of such an electron subject to the positive charge of the nucleus, as can be seen in the s orbital.

The s orbital corresponds to a standing wave (as in a plucked string) without a node, and that means that the path of the electron is only half the total Schrödinger wavelength. (A standing wave of the complete cycle would have a node, because one half would be positive amplitude and the other half would have negative amplitude.) Since the momentum of an electron cannot change during a quantum kinetic cycle, it seems that either a single cycle of the wavefunction must be responsible for both legs of its trip across the nucleus, or else a complete cycle of the wavefunction is responsible for each leg. In either case, the electromagnetic interaction between the electron and the nucleus involves a two-way motion across the s orbital.

Such a two-way, unit-like interaction would cause Lorentz distortions in the atom, as explained in the discussion of special theory of relativity, because the inherent motion is what mediates changes in the force field (and quantum potential) caused by the electron motion. Thus, when the atom has a high velocity relative to the inherent motion, the periods of the cyclic interactions between the electrons and the nucleus increases (causing a time dilation), and the difference between the one-way velocity of light in opposite directions in space changes in the longitudinal distance across which they act (causing a length contraction).

As we have seen, the relativistic increase in inertial mass is simply the addition of quantum kinetic cycles to the rest mass cycles, which determines the scaling factor for quantum kinetic cycle and determines the force required to change its momentum. Thus, the quantum nature of matter affords an ontological explanation of the Lorentz distortions, which should eliminate the suspicion that they are simply ad hoc assumptions contrived to defend classical physics from the Einsteinian revolution.

Heisenberg’s uncertainty principle. The Heisenberg uncertainty principle holds that it is not possible to measure both the position and momentum of a particle, or indeed both members of any pair of complementary variables, with arbitrarily high precision. According to the Copenhagen interpretation, this is because these classical properties do not describe the real nature of what exists at the most elementary level. Position and momentum are just properties we read into the world by using instruments designed to measure material objects according to principles of classical physics. Since both position and momentum are needed to predict what a classical particle will do, the Heisenberg uncertainty principle entails, at least, a limitation in what can be known, and it can be taken to mean that what exists at one moment does not determine what happens the next moment, or the denial of determinism.

The Heisenberg uncertainty principle is equivalent, as mentioned above, to the non-commutability of operators on the Schrödinger wavefunction:

When the Schrödinger equation is set up for a given situation, such as an atom or the two-slit experiment, the time-dependent Schrödinger wavefunction is a complete description of how interactions unfold over time. They unfold in a completely deterministic way, just like a classical wave function, except that the Schrödinger wavefunction uses complex numbers to describe the wave and it describes a wave in a configuration space with as many dimensions as three times the numbers of particles involved.

In order to make predictions from the Schrödinger wavefunction, mathematical operators must be applied. They generate real numbers as expectation values for the relevant property. But what is predicted is either just a mean value for many such measurements, that is, a probabilistic prediction, or if it does predict a precise value for the property involved, that property is one of a pair of complementary properties, and the other member of the pair cannot be predicted precisely.

In other words, classical properties come in complementary pairs that do not commute. The values predicted for such properties depend on which complementary operator is applied first. The application of an operator changes the wavefunction, so that the next operator is actually applied to a different wavefunction.

When a measurement is actually made, the quantum system turns out to have a property with a determinate value. The standard interpretation of what happens in such an measurement is called the “collapse of the wavefunction.”

What actually exists in the system represented by a Schrödinger wavefunction is assumed to be a superposition of all the states that might be revealed by a measurement. That is, states corresponding to all possible outcomes of measurements actually exist at the same time. Thus, what happens when a measurement is actually made is that the wavefunction collapses into one of those superposed states. The system is changed, and then another wavefunction describes the system, representing a different superposition of states.

Since there is nothing to determine which way the wavefunction collapses, this view denies determinism. In effect, it explains the truth of the Heisenberg uncertainty principle by the actual indeterminacy about what happens.

There is, however, no collapse of the wavefunction, according to ontological explanations of quantum mechanics along the lines presented here. In any quantum system, every particle with rest mass has a determinate position and momentum and follows a classical trajectory, and measurements reveal properties that the system actually has. Instead of giving the system the measured property, as the “collapse of the wavefunction” interpretation implies, measurement discovers which property the system already had.

This way of interpreting measurements of quantum systems is entailed by an ontological explanation, because it explains the properties and regularities described by physics as aspects of the substances constituting the world (and if it is to be genuinely explanatory, it cannot depend on any randomizing factor assumed as part of the basic nature of the substances constituting the world). But the price of holding such a view is explaining why the Heisenberg uncertainty principle is true. And that can be accomplished by explaining why the operators corresponding to complementary variables are non-commutable.

The ontological explanation of complementarity is just the quantum nature of matter. What “quantum” refers to ontologically are the elementary events of which everything but space is composed. Each quantum event is a unit, which either occurs as a whole or not at all, and every such quantum event has the size of a single quantum of action, denoted by h, Planck’s constant. This explains, as we have seen, both the particle-like nature of photons as well as the wave-like nature of particles with rest mass. In the case of such particles, the complementarity comes from the quantum nature of their kinetic energy, that is, from the nature of the form of matter that changes the locations of particles with rest mass. Kinetic energy is constituted by quantum kinetic cycles, implying that the motion of a rest mass involves a series of cyclic quantum events, each of which is a unit of action that moves the rest mass across space a certain distance during a certain period of time.

What ultimately causes the Heisenberg uncertainty is the quantum kinetic cycle. The velocity of a particle with rest mass moving through space depends on the wavelength of its quantum kinetic cycle, but the particle can have a range of different positions in space at the beginning and end of each quantum kinetic cycle. That is, each quantum kinetic cycle involves a certain phase as well as a certain wavelength. But since the particle is located in a potential field, in order for its energy level to be fixed, a different location at the end of each cycle may require a slightly different wavelength the next cycle. Thus, the quantum state of the particle is some combination of wavelength and phase at its energy level, but there are many combinations that might satisfy those conditions.

Both complementary properties cannot be measured with arbitrary precision at the same time, because they are different aspects of the same bit of matter, which is a series of cycle of quantum events, each of which can interact only as a whole. Either it interacts in a way that reveals the wavelength of quantum kinetic cycle, which leaves its phase undetermined, or else it interacts in a way that determines its phase (that is, the position of the rest mass at the beginning or end of a quantum kinetic cycle), and its wavelength is undetermined. But both cannot be measured at the same time, because a quantum event interacts only as a whole. And complementary aspects cannot be measured is succession, because such interactions change the cycles of quantum events.

The Schrödinger equation describes the motion of particles with rest mass in a potential field where there is a continual exchange between kinetic energy and potential energy, and on this ontological explanation, the wavefunction that holds for any given system describes the quantum kinetic cycles that result for such an interaction. I have suggested what such an explanation implies about the atom and the two-slit experiment, but it can be generalized.

One way that the Schrödinger wavefunction is different from a classical wavefunction is that it is complex. There are complex numbers, involving the square root of minus one, that cannot be eliminated, and that makes its relationship to the actual world problematic. On this ontological interpretation, however, they represent the different possible phases of the quantum kinetic cycles constituting the momentum of the rest mass cycles. That is, on our crude interpretation, the starting points and ending points of the quantum kinetic cycles can have different locations in space and time and still be quantum kinetic cycles of the kind that can exist under those circumstances. The complex numbers are a mathematical device for representing all those different possible phases and keeping track of how they affect one another.

The other way in which the Schrödinger wavefunction is different from a classical wavefunction is that it describes a wave in a configuration space with three times as many dimensions as there are particles in the system, and that also makes its relationship to the actual world of three dimensions problematic. On this interpretation, however, each of the 3-dimensional spaces is used to keep track of how the phases of the quantum kinetic cycle a particle involved in the system unfolds in time. Though the quantum kinetic cycles of all the particles depend on classical forces and laws, each particle needs a 3-D space of its own in order to represent all its possible phases separately.

When a mathematical operator is applied to the wavefunction and a prediction is made about the value of some property, the different possible phases for all the particles are all reconciled with one another, working out the interference effects they have on one another. And the prediction is still usually just a mean value for many experiments, because there is a range of different states in which the system might be at that point, depending on which precise phases and wavelengths the quantum kinetic cycles actually had.

The reason that operators on the Schrödinger wavefunction do not commute is that they predict two aspects of the same quantum event, such as the wavelength and phase of the quantum kinetic cycle (as in the explanation of the Heisenberg uncertainty above). It is possible to predict a property precisely when it has already been measured once. But the wavefunction that represents the quantum system as having that precise property cannot be used to predict the complementary property of the particle precisely. For example, when a measurement of the momentum has been made, there is an operator that can be applied to the wavefunction that will predict the momentum precisely. But then the phase cannot be predicted precisely, because quantum kinetic cycles with that wavelength can have different phases. The same holds in reverse if the phase of the cycle is measured.

The “hidden variable,” on this explanation, is space and how bits of matter coincide with it, because the quantum nature of the kinetic energy of the particles is the factor that determines what happens to the particles. They need a complete quantum kinetic cycle to get from one place to another, and thus, at the end of each quantum kinetic cycle, the forces picked up during that cycle are what determines the next complete quantum kinetic cycle. The interaction is step-like, and though I may be portraying it too crudely by thinking of the quantum events as having definite beginning points and ending points, the requirement that particles travel across space by such cyclic quantum kinetic events is what needs to be added in order to see how what happens to the particle is determined.

On this ontological explanation, therefore, the quantum system is deterministic, and we can understand in principle how it is determined. But it is not possible to overcome the Heisenberg uncertainty because of the nature of the quantum kinetic cycles that constitute the motion of particles with rest mass. They exist only as a whole or not at all, and thus, they are the smallest unit that can interact with other bits of matter as a unit, which means in only one way at a time. That is, the uncertainty comes from an incompleteness about the representation of the Schrödinger wavefunction: it represents quantum kinetic cycles, but it does not reveal which of all possible combinations of wavelengths and phases is actual.

This incompleteness interpretation of the Heisenberg uncertainty solves the problem of Schrödinger’s cat. Such cases arise when the phases of the quantum cycles interfere in such a way that the system can unfold in radically different ways. For example, in one case Schrödinger’s cat is alive and well, and in the other case it is dead. On the collapse of the wavefunction view, the Schrödinger wavefunction is a complete description of the situation, implying that what exists is a superposition of all the possible outcomes, and thus, since it turns out one way or another when someone looks, which one actually happens must depend on the measurement. But if which of the radically different alternatives is actual depends on the phases of their quantum cycles at the beginning, it is determined, and the uncertainty about what happens comes from that information not being included in the wavefunction representing the system. The incompleteness is inevitable, but that does not mean that it is indeterministic.

The phenomenon of tunneling can also illustrate the uncertainty. In tunneling, a charged particle moves past a force field that is classically strong enough to contain it. It occurs, for example, when there is a potential barrier separating electrons from protons attracting them that is just large enough to overcome the attractive force between them. But different electrons have different quantum kinetic cycles, setting up different patterns of spacetime cells in the inherent motion, and depending on whether they reinforce or cancel out the waves set up by the kinetic cycles of the protons, the force of attraction will sometimes be great enough for the electron to tunnel across the barrier.

The situation can be described by a Schrödinger wavefunction, which represents it as a packet of waves, each standing for a different possible combination of positions of the particles. As the situation evolves, however, the packet splits into two different parts, one in which electrons escape and one in which they do not. Thus, the equation represents two distinct channels, which subsequently do not interact. Which member of the packet is actual depends on precise locations and kinetic cycles of the particles (both wavelengths and phases). But they behave in a way described by the Schrödinger wavefunction because they follow the wave pattern set up by their kinetic cycles (See Bohm Ch. 5).

Bell correlations. The final quantum puzzle is the violation of the “Bell inequality” by certain quantum systems. John Bell pointed out that quantum theory predicts that there are correlations between distant events that cannot be explained without supposing that there is a causal influence of some kind that travels between them faster than the velocity of light.

Bell correlations occur when symmetrical particles, with opposite spin orientations, travel apart from one another in opposite directions and the spin of each is measured far away from the other. They always have opposite spin orientations when measured by imposing a magnetic field in the same direction in space. When one is up, the other is down. But the spin orientation they have in one direction of three dimensional space should not affect the spin orientation in either of the other two independent directions of space. And thus, the measurement of the spin of one of the separated particles in one direction should not affect the spin measured in the other particle in a different direction. Nevertheless, it is possible to use the measurement of the spin orientation of one of the particles in one direction to predict better than expected what spin the other particle will have when it is measured in an independent direction. That would be impossible, if spin orientation is a property that each particle has from the moment they separate and carry with them.

The greater than expected correlations are predicted by quantum theory. The prediction is made by applying the appropriate operators to the Schrödinger wavefunction for the system, and so the measurements are usually interpreted as involving a collapse of the wavefunction. That makes it seem as though the measurement of the spin of one of the particles helps determines which orientation of spin the other particle will have.

The Bell correlation is not only a prediction of quantum mechanics, but it has been confirmed by experiments.

Bohm (1993, Ch. 7) treats Bell correlations like any other puzzling phenomenon predicted by quantum mechanics, that is, as an indication of the quantum potential. Bohm is also giving an ontological explanation, but on his theory, the quantum potential is just a “non-local” aspect of the processes themselves, as if the common pool of information were broadcast faster than the velocity of light. Indeed, Bohm takes the world as a whole to have such a non-local aspect to it.

Non-locality seems to deny substantivalism about space, and that would make it incompatible with spatiomaterialism. If space is a substance, then what separates one part of space (and what happens there) from any distant part of space (and what happens there) are parts of space between them that have an existence that is distinct from both of them. Thus, the only way that this real separation between the parts of space can be overcome is by something traveling across space as time passes. To put it negatively, immediate action at a distance would seem to deny that there really is any substance between the distant points of interaction that is enduring through time distinct from them.

The inherent motion in space is a dramatic way of representing this fact about space as a substance. It is, perhaps, conceivable that Bohm’s non-locality is compatible with spatiomaterialism, because I have been speaking of the inherent motion in a more realistic way than may be necessary. That is, instead of thinking of space as containing an inherent motion, we can think of space as having a spatio-temporal geometry. Thus, what I have described as waves laid out in space by the inherent motion could likewise be just an aspect of the essential nature of space everywhere that always exists at the moment. That is, when the quantum kinetic cycle of a rest mass coincides with space, it has a certain wavelength and phase, and that wavelength and phase give it a different relationship to other parts of space with the same wavelength that are in phase with it than it does with those that are not in phase. Thus, what I have described as a particle “broadcasting” its wavelength and phase throughout space would be just a relationship that always already exists in the spatio-temporal geometry of space. If that were how the quantum potential is mediated, as Bohm assumes, it would explain the Bell correlation in the same way as other quantum phenomena.

I doubt that any such ontological explanation is adequate, however, because in order to explain interference phenomena in the two-slit experiment, for example, the quantum potential at any point in space would have to depend not only on the wavelength and phase of the particle, but also on the geometrical structure of the wall with two-slits. The waves laid out by the inherent motion that guide the particle to one of the fringes of the interference pattern must be singled out from all the other spacetime cells by the structure of the apparatus and how it fits together with the wavelength of the particle, and that would also have to be something about each location in space that always already exists for each possible arrangement of particles and wall with two-slits. This would be to attribute an enormously complex structure to the essential nature of space at every moment of its existence, and the complexity of such an explanation makes it look rather ad hoc. It would be a much simpler ontological explanation if the quantum potential were determined by an actual wave from the moving particle in the inherent motion that interacts with the two-slit wall, but that is not action at a distance.

There is, however, another explanation of the Bell correlations which is compatible with the principle of local action. Contrary to what many philosophers and physicists assume, what is actually known about this phenomenon does not force us to believe that the principle of local action is violated. There is a way of interpreting these phenomena that is compatible with explanation of the quantum potential by waves laid out in space by the inherent motion.

The predictions from quantum mechanics have to do with measurements of spin orientation, and they cover only those cases in which both events are actually measured. As a matter of fact, however, every experiment that can test Bell’s theorem involves many, many runs in which a measurement is simply not successfully made of one or the other particle (or of both particles). It is possible, therefore, that the cases in which both measurement are made are a biased sample. That is, if we could know the spin orientations in all the cases in which two particles split, it could turn out that their spin orientations in different directions were indeed independent and there is no Bell correlation.xlvii

Such a bias in the experiment cannot be just an accident. The many cases that must be ignored because no measurement was made must, for physical reasons, be mostly of a kind that, if included, would wipe out the improbable correlation between the distant events.

It may not seem like there can be any such factor, because the Bell correlations are predicted by quantum theory. That makes it seem that the Bell correlations are just another puzzling quantum phenomena, which manifest the same underlying mechanisms (whatever they are) as in any case of measurement. This is the assumption that is made in taking the correlation to involve the collapse of the wavefunction, except that unlike the other puzzling phenomena, it cannot be explained by the kinds of ontological causes described above, because Bell inequalities show that the collapse of the wavefunction involves action at a distance. That is, the hidden variable cannot be a local property, but must be a property that somehow holds of the whole system, including both particles, regardless how far they are apart at the time.

The prediction of the Bell correlation by quantum mechanics shows, however, only that some quantum phenomenon is involved. It may not, however, be the kind of phenomenon it is seems to be. The nature of intrinsic spin is not well understood, and it is treated as though it were completely described by the outcome of a measurement.

In the case of fermions, of particles with ½ spin, such as electrons, spin is measured by imposing a magnetic field and measuring the magnetic moment, that is, the force. The orientation of spin is simply the sign of that force, positive or negative: if the force is in one direction, it is spin up, and if it is in the other direction, it is spin down. Though that is how spin is measured, it is possible that particles have a more determinate spin orientation that is not measured in that way. An electron, for example, could have a precise orientation in three dimensional space, and though that is what determines the result of the measurement in the one direction that is singled out by the magnetic field applied, it also has other, more subtle effects on how the particle interacts.

In the case of photons, which are what has been used in the experiments that confirm the Bell correlations, spin is even more puzzling. Since the photon is a boson with a spin of 1, it should have three different possible orientations in a magnetic field, but since it moves through space with the velocity of light, one theoretically possible way of interacting is eliminated, leaving two possible orientations of spin. Opposite orientations of spin in the case of photons can be understood as opposite ways in which their electric force rotates as they move across space, one clockwise in the direction of motion and the other counterclockwise. However, it is usually measured by the polarization of the photon as it passes through a polarizer which is at rest and in which perpendicular directions, usually called vertical and horizontal, correspond to the two orientations of spin. But it is not clear why a rotation through a right angle would change whether a photon with, say, a clockwise rotation of its electric force, would pass through the polarizer.

In the case of both electrons and photons, there is enough uncertainty about the nature of spin and what is being measured that it is possible that the Bell correlations depends in some way on how spin orientation is measured. In either case, the three independent directions in which spin orientation (up or down or vertical or horizontal) can be measured are measured by an apparatus that is rotated in a two-dimensional plane perpendicular to the pathway of the particle. Thus, what may be a three-way symmetry among spins in three dimensional space is, in effect, reduced to a three-way symmetry in a two-dimensional plane. It is possible that in projecting that the three dimensional structure of spin orientations onto the two-dimensional plane of the measuring apparatus, some orientations of spin are more likely to pass by undetected than others, and they could be ones that would destroy the Bell correlation.

The selectivity may depend, furthermore, on an interaction between the actual orientation of spin in three dimensional space and the phase of its quantum kinetic cycle. Though the quantum potential that is responsible for interference and other real quantum phenomena requires a real effect propagating through space with the inherent motion, there could be an aspect of the waves set up in space by the inherent motion that makes all wavelengths with the same size and phase, wherever they exist in space, relate in a special way to the three dimensions of space. For example, the two particles have quantum kinetic cycles that are not only of the same wavelength, but also in phase with one another, and thus, if certain phases make it easier for them to interact from certain directions in three-dimensional space than others, the direction used by the detectors to test for spin orientation could result in a biased sample, making it appear that distant events are correlated. Such a factor would bias the sample in a way that makes it seem there are effect traveling faster than the velocity of light. And it would be local, because it depends only on the two particles having kinetic cycles that are in phase.

There is reason to think that some such explanation is correct, because Bell correlations occur only with measurements of spin orientation and the non-locality exhibited by the Bell correlations in measurements of spin is not an essential part of any other quantum phenomena. If it really were a result of action at a distance, it should be possible to make what happens at one location determine what happens elsewhere. But Bell correlations are not of a kind that can be used even to send signals from one place to another. In short, the Bell correlations are such a limited, subtle and questionable violation of the principle of local action that it would be foolish to use it as a reason for denying that spatiomaterialism can be used as an ontological foundation for a new way of doing philosophy, especially when that foundation works out so well in every other way.

Though much more would have to be said to show that this kind of ontological explanation of the nature of matter and space accounts for all the phenomena described by quantum mechanics, including quantum field theory and what it says about the nature of spin, this is enough to show that there is no good reason to believe that it is impossible to reduce quantum mechanics to spatiomaterialism. What is known by physics does not force us to give up the principle of local action entailed by this ontology, because neither experiment nor quantum mechanics is sufficient to demonstrate that the principle of local action does not hold. But this particular ontological theory is just a possibility introduced in order to speculate about a deeper explanation of the nature of matter and space, and what is relevant here is that, even this first approximation shows that there is no reason to believe that anything established empirically by quantum physics forces us to give up spatiomaterialism. There is at least one way that a two-substance ontology like ours can account for the quantum mysteries.

Let me emphasize, however, that it is not necessary to believe that what has been described here is completely accurate. It is only one of a family of ontological interpretations of quantum theory. What is common to the family is that the essential nature of matter involves the ability of bits of matter (of the same form) to exist independently of one another so that they can acquire spatial relations by being contained by different parts of space. There may be reasons for preferring another member of that family to this one. But this explanation of the quantum mysteries is enough to show that we do not have to give up the belief that space and matter are substances that exist continuously over time.

Cosmology. By “cosmology,” I mean the ontological explanation of those parts of the cosmos having to so with the extremes of the very small and brief and the very large and long-lasting. We have already explained ontologically the truth of the basic laws of physics governing the middle range involving ordinary material objects and their electromagnetic interactions. But as we recognized when we inferred to spatiomaterialism as the best ontological explanation of the natural world, the simplest and best form of any such ontology would hold that time, space and matter are infinite. Though we left open the possibility that a more complex ontological assumption may be required to explain certain phenomena, the ideal from of spatiomaterialism would hold that the universe is infinite.

The kind of infinity in question is twofold. Starting with the finite, there are two ways there could be an infinite series of steps, one by division into smaller and smaller finite units, and another by multiplication into larger and larger finite units. And there are three basic assumptions of spatiomaterialism to which it could apply: space, time, and matter. Let us consider where we stand on each of them.

Space. Space seems to be infinite in both ways, as we noted in Spatiomaterialism. There must be finite distances in space, for otherwise space would not have a geometrical structure at all. To hold that space has three dimensions is to hold that distances in it (and lengths of the objects coinciding with it) can be measured in three independent dimensions, say, by placing measuring rods down one after another. Each measuring rod is a unit, and since units that are parts of the same world can be counted [as established in Relations (Math)], distance measurements must obey the theorems of arithmetic, including division and multiplication. Thus, space can be infinite in two way, by an unending division of finite distances or by an unending multiplication of them.

If the division of finite distances in space is without end, space is continuous. That is what we have assumed, and we have found no reason to doubt that space is continuous.

If the multiplication of finite distances in space is without end, space is infinite in extent. That is the kind of spatiomaterialism that empirical ontologists must prefer, because it is the simplest assumption. Since the essential nature of each part of space includes its geometrical relations in three dimensions to every other part of space, an end to space in any direction would mean that every part of space has a different kind of essential nature from the rest, rather than the same kind of relationship to different particular parts of space. Not only would that complicate the nature of each part of space almost beyond recognition, but it would also be difficult, to say the least, to explain what happens at the end of space. As the ancient Greeks asked, What happens at the end of space? Does a spear thrown toward the edge of space bounce back?

Thus, we assumed that space is infinite in extent. But we acknowledged that we might have to revise that assumption, for that is the prevailing belief among bit gang cosmologists and a spatiomaterial world in which space is not infinite is possible.

Time. Time seems to be infinite in both ways as well. There are finite periods of time. There must be, because there are cyclic processes involving real change. Since such cycles are units that can be counted, the theorems of arithmetic must be true of measurements of time, including division and multiplication.

If the division of finite periods of time is without end, time is continuous. There is every reason to believe that time is continuous, because space is continuous and space has an inherent motion. If the division of time were not as unending as the division of space, there would be no explanation of motion, because objects could not occupy continuously connected parts of space as they endured through time. (And the original and still most basic employment of the calculus to represent motion in a way that overcomes Zeno’s paradox about motion would be a misrepresentation of the world.)

Furthermore, spatiomaterialism is committed to the continuousness of time, because it is entailed by the assumption of an inherent motion in space as an aspect of its essential nature. Each distance in space corresponds to a period of time, and thus, if space is continuously divisible, time must also be. (To be sure, it is not possible to measure space by the velocity of light because of the Lorentz distortions, and even if we could, it would not necessarily tell us about space itself because of the acceleration of the inherent motion in gravitational fields. But the relationship between space and time, though complicated in these ways, requires time to be continuous, if space is.)

If the multiplication (or addition) of periods of time is without end, time is infinite in extent, or what is called “eternal.” The eternity of the world is entailed by spatiomaterialism, because it assumes that existence is in time. That is, spatiomaterialism assumes that the world is constituted by substances of kinds that never come into existence nor ever go out of existence, but rather endure through time. That is what enables it to explain change as really occurring as time passes. Given its view of time and existence, spatiomaterialism cannot believe that there was a beginning to the world, because that would be to hold that something comes from nothing. Nor can spatiomaterialism hold that the world stops existing at some point, for that would be to hold that what exists can become nothing.

Matter. Given our ontological explanation of quantum mechanics, however, matter can be infinite in only one way. The existence of ordinary material objects shows that there are finite accumulations of matter, and since they are units that can be counted, theorems of arithmetic are also true of matter.

If the multiplication (or addition) of matter is without end, matter is infinite in extent, that is, the total quantity of matter in the world is infinite. There is no reason to doubt that the quantity of matter is infinite, if space is infinite, because there is no reason to believe that only a finite region of space has bits of matter coinciding with it. On the other hand, if space were not infinite, matter could not be infinite, at least not ordinary matter, because there would be no room for all of it.

We know, however, that the division of matter cannot go one without end, because the theory of quantum matter holds that each bit of matter is constituted by a series of cyclic quantum events, each with the size represented by Planck’s constant, h. The spatiomaterialist explanation of quantum mechanics is based on the assumption that quantum events have a unit-like nature in which they either exist as a whole or not at all.

To be sure, force-field matter, such as electromagnetic and gravitational fields, may be infinitely divisible. But that is because force field are just properties or conditions that are imposed on space by quantum matter, and the quantity of matter they contain is already counted in the rest masses of the material objects exerting them (except in the case of gravitational waves, which are eventually converted in quantum events as they accelerate bits of matter). Quantum matter is the basic form in which matter endures through time as a substance.

At this point, therefore, spatiomaterialism still takes space and time to be infinite in both ways and matter to be infinite in extent, though only finitely divisible. The final question in this ontological explanation of physics is, therefore, whether spatiomaterialism can keep this simple form. Do its assumptions about space have to be more complicated in order to acknowledge that space and matter are finite in extent? Can its assumption that matter is not infinitely divisible be squared with what physics knows about the basic objects? And do we have to accept that time is not eternal and admit that spatiomaterialism is just an effect of a deeper, theistic ontology in order not to give up ontology altogether? These are the cosmological questions that spatiomaterialism must answer. The issues to be addressed can be separated into two sets, one having to do with the finite divisibility of matter and the other having to do with the infinite extent of space and time.

Finite divisibility of matter. Though spatiomaterialism has assumed that matter is constituted by cyclic quantum events in order to explain the truth of quantum mechanics, it had to take for granted that electrons and the nuclei of atoms can be explained in as a form of quantum matter. This is clearly not the deepest truth about nature, since physics has found other particles like electrons that are much heavier, and some that are massless and carry not electric charge at all. And it has discovered not only that the atomic nucleus is composed of protons and neutrons, but also that such nucleons are composed of quarks, not to mention the two short range forces involved in the interactions of its basic objects.

The main question is not whether the rest masses of the basic objects of physics can be explained ontologically as forms of quantum matter. There is not much reason to doubt that it is possible to give such a spatiomaterialist ontological explanation, though some might find it reassuring to see how it works out in more detail. But there is a reason to take up the issue of the nature of the most basic objects here. It is another opportunity to show the fruitfulness of an ontological explanation of the world based on spatiomaterialism.

Physics now recognizes some 38 different kinds of basic particles (counting antiparticles, but not the three colors of each quark), and though they are a far less unruly lot than the particles recognized by physics thirty years ago, they are still an odd lot. Part of the problem is that the four basic forces of nature have not yet been fully unified. Even if we count the so-called electroweak force as the unification of the electromagnetic and weak forces, the strong force still resists assimilation as part of a single gauge theory, and as we have noted, physicists are at wits ends about how to represent gravitation as another force of the same kind. Particle physicists believe that there must be a deeper theory, but the dramatic progress of high energy physics during the 1970’s and 80’s has come to a halt in the 1990’s. And they are still pursuing the “holy grail” of physics, a single mathematical law from which the laws describing all the forces of nature can be derived.

The possibility that is not even being considered in this effort is explanatory ontology. As we shall see, by recognizing that space is a substance, it is possible to reduce all the basic particles of physics to nine or ten kinds of particles (including antiparticles). Indeed, it may even be possible to formulate spatiomaterialism in a way that reduces everything to just three basic particles — and space, of course, as the substance with which they coincide.

Infinite extent of space and time. In the direction of very large and very long-lasting, spatiomaterialism must be false, if contemporary cosmogony is correct, because it is currently assumed that the universe began with the big bang and has been expanding ever since. Indeed, the prevailing theory implies not only that the universe had a beginning in time, but also that space and matter are finite in extent. And some even interpret it as imply that the universe might simply drop out of existence at some time in the future (if it collapses because of gravitation), implying that time is also finite in the direction of the future. There are both theoretical and empirical reasons for believing that the universe began with a big bang and continues to expand, though as we shall see, spatiomaterialism can be defended against both.

On the theoretical side, Einstein showed how his general theory of relativity could be used to represent the universe as a whole, and with a relatively minor revision, that approach can be used to represent the expansion of a universe being contracted by gravitation in a mathematically precise way. That is the Einstein-de Sitter model, as it is widely accepted by cosmologists as explaining the expansion of the universe.

The empirical reasons are Hubble’s discovery of a correlation in galaxies between their red-shift and distance which suggests that galaxies are all rushing away from one another, the discovery that the proportion of hydrogen and helium in the universe is explained by their synthesis shortly after the big bang, and the discovery of a cosmic background radiation that seems to be the left over from the big bang (with wavelengths elongated by the expansion of space in the interim).

Spatiomaterialism can, however, be defended against both kinds of reasons. Its critique of Einsteinian cosmology is based on the spatiomaterialist explanation of the truth of Einstein’s general theory of relativity and its explanation of the relationship between gravitation and the other basic forces of nature. And spatiomaterialism offers another way of explaining all the empirical evidence for the big bang and the expansion of the universe. It is an approach to cosmological issues that is not even being considered these days. Not only is it a plausible defense of spatiomaterialism, but it also illustrates the fruitfulness of spatiomaterialism in opening up new ways of explaining natural phenomena.

Let me emphasize, however, that it is not necessary to defend such a cosmological theory in order to spatiomaterialism as the ontology for our new way of doing philosophy. What physics has discovered about the basic particles does not even suggest that spatiomaterialism is false, and like quantum mechanics, we could simply take it for granted that a spatiomaterialist theory can be formulated. To be sure, big bang cosmogony does contradict spatiomaterialism. But scientists generally are not confident enough of its conclusions to use them as a reason for dismissing spatiomaterialism out of hand. Popular culture seems to be confident of the big bang, and the Church has welcomed it warmly. But among scientists, cosmology is still a matter of hot dispute.

There is, however, a point in carrying this project to the extremes of the very small and brief and to the very large and prolonged, because it turns up certain advantages of recognizing that space is a substance. There are straightforward ways of elaborating spatiomaterialism into an ontological explanation of cosmological phenomena, and hopefully it will do not harm to suggest them here.

This part the spatiomaterialist ontological explanation of the world is even more speculative than its explanation of quantum mechanics. It is included here in the spirit of exploration. By offering an ontological explanation, I do not suggest that these problems can be solved in the end without the use of mathematics to calculate quantitatively precise predictions and the attempt to make the appropriate measurements. Ontology is a deeper explanation than the efficient-cause explanations of empirical science, but it is not a substitute for them. An ontology must be able to explain why those efficient-cause explanations are true in order to be adequate.

Physics is, however, so dependent on the use of mathematics for representing the world that it has given up the intuitive insights that would come from recognizing that the world is constituted by space as well as matter. In explaining the truth of the special theory of relativity, the general theory, and quantum mechanics, we have seen how ontology offers a more intuitive explanation of these phenomena, one that uses our capacity to imagine space and time to think of space and matter as substances enduring through time and, thereby, constituting the natural world. Thus, it would not be surprising at this point, if, together with the enormously powerful constraints that mathematical theories impose on what is possible, the attempt to formulate an ontological explanation illuminated possibilities in the vague darkness that lies beyond what is firmly in the grasp of experimental physicists that turn out to be true.

Though I claim that the following theories are true, I am not claiming that the following explanation is the only possible spatiomaterialist explanation of cosmological phenomena, nor even that it is the best. My only claim is that it is a spatiomaterialist ontological explanation, and it does enable us to discuss these issues in a new and illuminating way. It explores an avenue that physics will travel, when it acknowledges that ontology is explanatory and uses the empirical method to infer to the best ontological-cause explanation, not just the best efficient-cause explanation. But even before it proves itself in that more demanding arena, it is possible to get a glimpse of how how the world is whole even at the extremes of the very small and the very large.

Basic objects. Let us first extend this ontological explanation in the direction of the very small and the very brief. The place to begin is with the so-called “Standard Model” of physics and the inventory of the basic forces and particles included in it. (A history of the history of particle physics by one of the participants that I would recommend is 't Hooft (1997)).

Basic particles of physics. In order to set the scene for inventorying the basic particles of physics, I will first describe more fully a basic difference that physics recognizes between two kinds of basic objects, fermions and bosons. Gauge field theories hold that forces are mediated by bosons, the so-called gauge particle of the underlying field, and the next step will be to describe the two forces of nature in these terms. That will put us in a position to list all the kinds of basic particles currently recognized by contemporary physics.

Fermions and bosons. The most fundamental difference among basic objects in space is that between fermions and bosons. (It is basic to the Yang-Mills field theories which are currently used to explain the basic forces.) This difference is exemplified by electrons and photons. As a first approximation, fermions, such as electrons, are the material objects on which forces the work, whereas bosons, such as photons, are the forces that work on them. Though the difference is more subtle, this contrast points to the basic difference in their roles.

Fermions are basically particles that exclude one another from occupying the same quantum state, whereas bosons are particles that tend to fall into the same quantum states. To put it more precisely, fermions obey the Pauli exclusion principle, while bosons do not. They behave according to Bose-Einstein statistics, as opposed to Fermi statistics.

The difference between them is the kind of intrinsic spin they have. Spin is the quantum mechanical version of a rotating object with an electric charge. It is a measure of the magnetic moment exerted by the particle when a magnetic field is imposed on it. But there are two different kinds of spin, distinguishing fermions and bosons.

The Pauli exclusion principle holds of any particle with some multiple of ½ spin (. .-5/2, -3/2, -1/2, 1/2, 3/2, 5/2, , ,) whereas Bose-Einstein statistics hold of particles with an even number of spin (. .-2, -1, 0, 1, 2, . .). The spin indicates the number of different forces the particle might exhibit when a magnetic force is imposed on it from a certain direction. The number is equal to 2s + 1. Thus, a particle with 1/2 spin can exert one of two possible forces when placed in a magnetic field, either positive or negative (up or down), whereas a particle with spin of 1 can have one of three values, positive, negative, or zero. Among the basic particles, however, there are only three kinds: particles with ½ spin, particles with a spin of 1, and particles with a spin of 0. The other values of spin come from combining basic particles. (Actually, Yang-Mills field theory recognize only particles with a spin of ½ and 1, but it has been necessary to add particles with 0 spin in order to explain the rest masses of particles.)

Fermions have the nature that makes them most like ordinary material objects, for they exclude one another from occupying the same place at the same time. The structure of the atom, for example, depends mainly on the Pauli exclusion principle. The various electron orbitals are distinct quantum states, and since electrons are fermions, only one electron (of each kind) can occupy each orbital. (The reason that there are usually two electrons in each orbital is that there are two opposite kinds of electrons, spin up and spin down, and one of each kind can fit into each orbital.)

Bosons are the particles that mediate the forces of nature, and they are called particles of the underlying field. Whereas basic fermions are point-like in the sense that they are located at each moment at a certain point in space, bosons have a nature more like space itself, because they emerge from the underlying field to mediate its forces.

Particles susceptible to a force are said to have a “charge,” but in order to conserve the charge so that it does not disappear (or multiply) as the particles move and interact, the force field laid out in space associated with the charge generates bosons, or forces, that act on the particle in certain ways, changing its motion or even its kind. This is called “local symmetry,” but it is basically the regularities about the particle that must hold in order for the “charge” to be unchanged.

One basic difference between electrons and photons does not, however, hold generally for fermions and bosons. Electrons have a rest mass, whereas photons are massless particles. But this contrast in rest mass crosscuts the distinction between fermions and bosons. There are massless fermions and massive bosons.

Though most fermions have rest mass, there is one set of fermions that, as far as physics can tell, do not have any rest mass at all. They are called “neutrinos,” which are affected only by the weak force (see below). Theory does not require them to have a rest mass, and experiments have made it clear that the maximum mass they can have is about 12 eV.xlviii With a spin of ½, neutrinos should have two possible orientations of spin, but in this case, having opposite orientations of spin is what distinguishes each kind of neutrino from its antineutrino. Normally, antiparticles have opposite electric charges, but neutrinos have no electric charge, and the opposite orientation of spin is equivalent to having an opposite weak charge. The neutrino has left-handed spin in the direction of its motion, and the antineutrino has right-handed spin. They are mirror images of one another. (As massless particles, the fact that each kind of neutrino has only one orientation of spin, despite having a spin of ½, could be explained in much the same way as it is explained in the photon: one orientation of spin is lost because they move at the velocity of light, because they cannot stop to turn around so that they can interact from the other direction.)

Though photons are massless, there are bosons with mass. Mass would be expected in bosons that are merely fermions locked together in a way that neutralizes (or combines) their opposite orientations of space so that they have a net spin that is an even number, such as the helium atom. But bosons that are basic particles mediating the forces of some underlying field are expected to be massless, and thus, the discovery that the bosons mediating one of the basic forces of nature have rest mass (the weak force) posed a problem that had to be overcome. Let us turn, therefore, to the basic forces of nature.

Basic forces of nature. Physics recognizes four forces in nature (gravitation, electromagnetism, the strong nuclear force, and the weak force), and attempts to knit a mathematical description of them into a single, uniform deductive system have used the mathematics of gauge field theory (Yang-Mill gauge invariance). Since bosons are the kind of particle that emerge from the underlying field to mediate those forces, they can be called gauge bosons.

Electromagnetic force. We have already seen how the electromagnetic force can be explained ontologically, and in passing, I have mentioned the gauge field theory of electromagnetic interactions.

Basically, the electric charge is represented as having an orientation in a complex field, and the electromagnetic forces affecting it are what is required for local symmetry, that is, for the charge to keep the same orientation in the complex field as the particle changes location in space.

What I have described as the force field matter of an object with rest mass is a way of referring to the electric charge of such a particle, and the gauge field theory about how it works can be explained ontologically by thinking of the force field matter of an electric charges as something that is imposed on space in a cyclic way as time passes, as if the force were sent out from the object in regular pulses. If the pulses of all negative charges throughout the universe were synchronized, it would be possible to explain what is meant by “orientation in a complex field,” for it would be the phase in that cycle. Negatively charged particles would all be pulsing at the same time, jointly setting up the force field in which they are located. The pulses would propagate at the velocity of light, since they are mediated by the inherent motion in space. And since the force field that acts on the charged object is pulsating, its charge must remain synchronized with the field, even though the particle may be changing locations in space. Gauge bosons emerge from the field to keep the charge synchronized, but they can do so only by exerting forces on the particle that can change its motion, accelerating it in one direction or another. Those forces are the electric and magnetic forces described by Maxwell’s equations, and the gauge boson is the virtual photon mentioned in explaining the quantum structure of the atom. Virtual photons carry momentum and kinetic energy between charged particles and the force-field matter the particles jointly spread out in space by their pulses. They are the spin 1 particles that mediate the electromagnetic force.

The difference between positive and negative charges could be explained on this ontological explanation as having pulses with opposite phases in that universally synchronized cycle. Particles that pulsate in phase would repel one another, whereas particles that are pulsing out of phase with one another would attract one another. This dependency of the direction of the force on the phase of the universal pulsation is the reason that there must be virtual bosons to keep charges synchronized with the universal pulsation as the charged particles move across the force field they help set up (the force-field matter that comes from all the particles).

Partial electric charges could likewise be explained as phases relative to the universal electromagnetic pulsation (or as orientation in the complex field) between the extremes of negative an positive. But in order to take account of the magnetic force, the complex field in which charges are oriented may be twofold, and the pulsation correspondingly compounded.

[The mathematics of quantum electrodynamics, and gauge field theories generally, makes it difficult to figure out how a particle will move and interact in the field. Richard Feynman discovered a relatively simple way of doing so by identifying the path of least action from all the possible paths the particle could follow (which is ontologically, the path requiring the fewest quantum cycles). He showed how it could be identified by rules for canceling out more complicated, symmetrically opposite pathways and seeing what remains. This was the foundation for his famous “Feynman diagrams,” which depict electromagnetic interactions between particles as being mediated by the exchange of photons. But the mathematics involved is suspect in the minds of many, because the calculations lead to infinite quantities, which can be eliminated only by hand, canceling out those that are opposed symmetrically, in a process called “renormalization.” There must be a deeper explanation of what is going on.

[This aspect of quantum electrodynamics and other gauge field theories can be explained ontologically, I believe, in a way that involves the waves we have assumed are sent out in the inherent motion by quantum kinetic cycles. The symmetries that Feynman uses to determine the path of least action can ultimately be explained ontologically by the constructive and destructive interference of such waves (much as I have used them to explain Bohm’s “quantum potential”). But it is more complex, because the particle is carrying an electric charge through the force field, and if the force field involves a universal pulsation which constitutes the difference between positive and negative charge, the virtual photons must be synchronized with it in order to conserve the electric charge. I suspect there is some such ontological explanation, but it would take a better grasp of the mathematics than I have.]

Strong force. The strong force is the force that accounts for the nucleus of the atom. Being is about 100,000 times stronger as the electromagnetic force, it holds protons and neutrons together despite the strong repulsive forces among the positively charged protons. The strong force does not affect electrons or neutrinos (or other particles of their kinds).

The particles involved in the strong force are called “hadrons,” both the particles affected by it and the particles whose exchange mediates it. The strong force that holds the nucleons together is mediated by the exchange of mesons (such as pions). But protons and neutrons are only a two of many kinds of “baryons” that have been discovered by accelerating particles to collide with one another at very high energies, and various kinds of mesons have also been found mediating interactions among them.

The neutron, for example, decays into a proton, an electron, and an electron antineutrino, and there are many other kinds of baryons that decay into protons or neutrinos, with similar kinds of debris. The negatively charged pi meson (pion) decays into a negative mu lepton (a heavier cousin of the electron) and an mu antineutrino. Again, there are many kinds of mesons with various decay patterns, so of which decay by way of a pion.

The attempt to explain the diversity in the kinds of baryons and mesons has led to the recognition that hadrons are all composed of simpler objects, called “quarks.” Baryons are constituted by triplets of quarks, and that mesons are constituted by quark-antiquark pairs. There are some six different kinds of quarks, each with an antiquark, though only the two lowest energy quarks (u and d quarks) are found in the nucleons of ordinary matter. Half the quarks have a negative electric charge of 1/3, and half have a positive electric charge of 2/3 (with their respective antiquarks having electric charges with the opposite sign).

Interactions among quarks are mediated by the "color" force. That is, quarks have a “color charge” which makes them susceptible to the color force, and quarks interact with one another by exchanging gluons, the gauge particles of the color force. Gluons are, therefore, bosons with an intrinsic spin of 1. They are massless particles, like the photon. But unlike the photon, gluons are themselves subject to the color force, that is, they exert color forces on one another as well as on quarks. Photons, by contrast, do not interact at all, except for their tendency as bosons to fall in step with one another.

The color force has an unusual strength that keeps quarks confined in triplets to baryons. When quarks are very near one another, the color force is not very strong. But when the distance is increased, the color force increases along with it. And if the distance increases enough for the potential energy (or force-field matter) to constitute a quark and antiquark pair, matter takes that form. The quark of the new quark-antiquark pair replaces the quark that was being moved out of the baryon, and the antiquark combines with the original quark from the baryon to constitute a meson, which quickly decays.

In order for three different quarks of the same kind to help constitute a single baryon, there must be three different “colors” of each kind of quark. And according to the symmetry of the theory, eight kinds of gluons are needed to mediate all the forces that hold among three different kinds of quarks in constituting baryons.

Weak force. The weak force has long been recognized because of the need for some force to explain the radioactive decay of natural substances, such as radium. Natural substances send out particles with rest mass from time to time which can be detected, and since that suggested that they were somehow coming apart, a force was needed to explain how it could happen.

The weak force was soon also used to explain the decay of hadrons (baryons and mesons) into more common particles, such as neutrons, protons, electrons, and neutrinos, which were observed in high energy collisions of particles in accelerators. Indeed, there are also higher energy particles like the electron, such as the muon and tau particle, which decay into the electron and an antineutrino (or if they are positively charged, decay into a positively charged electron, or positron, and neutrino), and those decay patterns were also attributed to the weak force.

In order to explain these decay patterns on the model of gauge field theory, it was recognized that every kind of particle carries a “weak charge,” which makes it susceptible to the weak force. The weak force is mediated by a kind of particle, which was originally called the “intermediate vector boson,” but is not referred to as the “weak boson” or “weakon.” As the gauge particle of the weak force, the weakon is a boson with spin 1, and in order for electric charge to be conserved in decay by the weak force, there had to be two different kinds of weakons, one with a positive and one with a negative charge (W- and W+).

It is called the weak force, because it is so much more difficult to make particles interact in this way than by the strong force (or even that the electromagnetic force, which is about 100 times weaker than the strong force). (The weak force is about 10-6 times the strength of the strong force, whereas the electric force is 10-2 times the strong force.) According to recognized principles, the weakon could still actually be a force comparable in strength to the photon, if the weakness of the weakon were due to having a considerable mass. But the assumption that the weakon had such a mass spoiled the gauge theory: the weakon could no longer represented by Yang-Mills mathematics.

In one of the most famous discoveries of the past few decades, Weinberg and Salam independently discovered a way to give the weakon a mass without spoiling its role as the particle of a gauge theory. This was to postulate the so-called Higgs boson and to assume that such particles exist everywhere in space. The Higgs boson has a spin of 0, lacking any orientation at all in a magnetic field. But to postulate their existence everywhere in space was to postulate the existence of a new field that has minimum energy when it is exerting a force everywhere in space. That force could be used to explain why a boson, such as the weakon, that is otherwise massless has a mass.

Weinberg recognized that this explanation of the mass of the weakon implied that, in addition to the negatively charged and positively charged weakons, there is a weakon that does not carry an electric charge at all (Z0). Interactions involving the Z0 would not change the electric charges of the particles, but only their motion, as in an elastic collision, and when evidence for such “neutral currents” was found, it was recognized that Weinberg had discovered a theory that explained both electromagnetism (how charges interact by way of virtual photons) and the weak force (how particles generally interact by way of virtual weakons). It is sometimes called the “electroweak force.” (The color force, however, resists assimilation to that theory. Though it is possible to construct the appropriate equations describing gluons as the gauge particle mediating interactions among quarks (and gluons), it has not been possible to figure out what the equations imply.)

Gravitation. The success of gauge field theories in representing the other forces of nature has led to attempts to represent gravitation as force that is likewise mediated by the exchange of particles from an underlying field. The “charge” on which the gravitational force works is mass, and the gauge particle that mediates the gravitational force is called the “graviton.” However, in order to serve this function, it must be a boson with a spin of 2, and the attempt to integrate this force with the other three forces of nature what has led to superstring theory and the belief that there are as many as ten dimensions to space.

Though the mathematics of superstring theory is supposedly elegant, the need to recognize additional dimensions of space, if nothing else, makes it suspect. And it can be avoided, as we have seen, by recognizing that space is a basically different kind of substance from matter. Assuming that there is an inherent motion in space by which bits of matter coincide with parts of space (and that is possible, as we have seen, by the spatiomaterialist explanation of the truth of Einstein’s special theory of relativity), gravitation can be explained as an acceleration of an inherent motion in space. That is the spatiomaterialist explanation of Einstein’s general theory of relativity.

This is a radical departure from contemporary physics, because without recognizing that space is a substance, it has no other way to explain gravitation than as just another field that holds among particles. That is what leads to the belief that gravitation is mediated by gravitons and poses what is the most formidable problem for contemporary physics: connecting gravitation with the other forces of nature.

Substantivalism about space makes it possible, however, to explain basic particles in a way that may be similar to superstring theory, but without the extra dimensions.

Catalogue of basic particles. Let us catalogue the basic objects that are currently recognized by physics, and then we shall see how we might account for all of them quite simply, given our ontology. The objects that are currently taken to be basic include both bosons and fermions.

The bosons are the particles mediating the forces. According to current gauge theories, there are bosons for each of the four forces, including the graviton to mediate the gravitational forces. (See diagram of Basic Particles of Physics.)

Current explanations of the weak force requires the postulation a Higgs boson, with a spin of 0, to give weakons (and other particles) their rest masses.

Three weakons mediate the weak force: W+, W-, and Z0, each with a spin of 1.

The photon is the gauge boson that mediates the electromagnetic force. It also has a spin of 1.

Eight gluons mediate the color force, each with a spin of 1.

The graviton is the boson that is supposed to mediate gravitational forces, but it can be set aside, since I have already explained gravitation without the need for any such particle.

Fermions are particles that obey the Pauli exclusion principle and have a point-like location in space. There are two broad classes, leptons and hadrons. The hadrons are distinguished by their susceptibility to the strong force, while leptons are immune. Electrons are the most famous members of the lepton group. Their masses are well defined, and their name, meaning “light ones,” comes from being so much lighter particles than hadrons (and even than quarks). But some physicists suspect that neutrinos may not be quite massless. There are six leptons in all, and each has an antiparticle.

The first family of leptons includes the electron and the electron neutrino. The electron has a charge of –1 and a mass of 0.5 MeV/c2, whereas the electron neutrino has no charge and there is not much reason to believe it has any mass at all. The antiparticle of the electron is the positive electron, or positron, with a charge of +1, and the antiparticle of the electron neutrino is the electron antineutrino, with neither charge nor rest mass.

The second lepton family is composed of the muon and the muon neutrino. The muon has a negative charge and a mass of about 106 MeV/c2,whereas the muon neutrino has no charge and no rest mass. Again, both members of this family of leptons have an antiparticle, the positively charged muon and the muon antineutrino, without any charge or rest mass.

The third lepton family is composed of the tau particle, with a negative charge and a mass of 1784 MeV/c2 and the tau neutrino. Both have antiparticles with properties similar to the first two families of leptons.

Hadrons are the objects affected by the strong force, and they are made of quarks, as we have seen. (Baryons have three quarks each, whereas mesons are made up of a quark and antiquark.) Let us inventory the quarks, since hadrons have already been reduced to them. Most commentators are struck by how the quarks also fall into three families, with two particles each, both with antiparticles.

The first family of quarks includes the d and u quarks, and an antiparticle for each. The d quark has a charge of -1/3, while the u quark has a charge of +2/3, setting the pattern for all three families. The masses of quarks are not well defined, because they cannot be released from confinement in baryons or mesons, but the d and u quarks do not appear to be over 100MeV/c2 (and may be considerably less). Their antiparticles are antiquarks, with opposite electric charges, that is, anti-d, with +1/3 and anti-u, with –2/3.

The second family includes the s quark and the c quark, and their antiparticles. The s quark, with a charge of –1/3, resembles the d quark, but it has a mass of about 200 MeV/c2. The c quark likewise resembles the u quark, except it has a mass of about 2000 MeV/c2. Their antiquarks have the same masses, but opposite electric charges.

The third family includes the b and t quarks. The b quark resembles the d and s quarks, with a charge of –1/3, while the t quark, with a charge of +2/3, resembles the u and c quarks. Again the main difference is in mass. The b quark has a mass of about 5000 MeV/c2, while the t quark has a mass of about 175000 MeV/c2. Their antiquarks have opposite electric charges.

The accompanying diagram listing all the basic particles recognized by physics suggests the deep symmetry that is believed to hold between the quarks and leptons. Each has three families; two members have different electric charges; all particles have antiparticles, and all are subject to the weak force. Together with the bosons required for the three forces of nature, including gravitation, there is a total of 38 particles. (But there are only 37 to explain, since gravitation has already been explained by the nature of space as a substance.)

A spatiomaterialist theory of basic particles. The basic particles of physics are described by mathematical theories, which have been accepted as the best efficient-cause explanation of precise, surprising measurements, and they constrain what can be said about basic particles in many subtle ways. What I will present here is, by contrast, a mostly geometrical story about the basic particles, or rather, the beginnings of a geometrical theory. It comes from using spatiomaterialism and its explanation of other parts of physics to constrain further our beliefs about the basic particles. They must be constituted by bits of matter that coincide with space in some way or another, and since space has a three dimensional geometrical structure with an inherent motion connecting all the parts of space in time, these most basic forms of matter must have a spatio-temporal structure of some kind. What is presented here is one way that could be true. There may be other ways it could be true. And the one presented here is merely the model for a set of more specific theories that may be elaborated in different ways. My purpose is to show how adding the ontological constraints of spatiomaterialism to the mathematical constraints of the standard model opens up the possibility of a geometrical model of the basic particles.

It is, once again, an ontological explanation of why current theories about the basic particles are true, and its advantage over purely mathematical theories is that it reduces the number of basic assumptions that need to be made. To be sure, spatiomaterialism makes a big assumption that contemporary physics does not make — that space is a substance enduring through time, indeed, one with an inherent motion. But that will enable us to reduce the 37 particles recognized as basic by contemporary physics to, at most, only ten particles. Or even fewer, it might be argued, though that issue can be put off until we discover whether such ontologically based speculation is useful.

The ten basic particles we shall postulate are the photon, the three weakons, W-, W+, and Z0, three neutrinos, electron, muon and tau, and their three antineutrinos. In one way or another, each involves a new assumption about the nature of matter, space and how they are related.

But it is conceivable that the photon can be explained as another form of weakon, and the six neutrinos may be just properties of space, that is, aspects of its relationship to weakon. Hence, a spatiomaterialist world may be made of nothing but space and three kinds of weakons.

This explanation of the nature of the basic particles is based on the assumptions we have already made about the nature of matter in order to explain the truth of the basic laws of classical physics, relativity theory, and quantum mechanics. Quantum matter is ultimately constituted by quantum events, which are basic and can coincide with space in various ways, and since they are cyclic, they constitute bits of matter that endure through time. The total energy or mass of a bit of quantum matter is simply the number of quantum cycles per second that constitute its existence. Since the photon is the simplest and plainest form of quantum event that we considered, let me recall what has been said about it.

An independently existing photon is a complete cycle of electric and magnetic forces. Those forces interact in a way that enables them to be repeated indefinitely. But since each cycle is a quantum event with the size of Planck’s constant, h, it either occurs as a whole or not at all. The total energy, or matter, in a photon depends on the number of cycles per second, as required by the physical law, E = hf. But the photon coincides with space in a way that makes it move with the inherent motion in some direction of space. Thus, it also has a wavelength,  which is inversely proportional to its momentum, as required by the equation, p = h/

The photon has an intrinsic spin of 1, which implies that there are three different ways it could be oriented in a magnetic field. Two faces have a magnetic moment, positive or negative, corresponding to the two ways that light can be polarized. (If you follow the photon through space, the electric force rotates around to the right or left in space, which determines it circular polarization, but the difference between these properties is quantum mechanically equivalent to photons being polarized in mutually perpendicular directions as they pass through a filter.) And the third way that a spin 1 boson can interact in a magnetic field involves having no magnetic moment at all, as if there were a face in which the two possible orientations of spin were perfectly balanced. But the photon apparently loses the ability to interact from that “zero face,” as I will call it, because it is moving through space with the inherent motion.

Though the photon has energy, it has no rest mass. It might make it seem that its energy must come from its motion across space, like a form of kinetic energy. But that is not quite right, if its motion is due to the inherent motion in space. We are assuming that its energy comes from the cycles of quantum actions that are carried out by the exertion of electric and magnetic forces.

The photon is the gauge boson of the electromagnetic field, and on our ontological interpretation of gauge field theories, that means that electric and magnetic forces arise from space to act on a particle with an electric charge when it moves across space. At rest, the charged particle is a pulsating force in the surrounding space, which is synchronized with the pulsations of particles with the same charge throughout the universe (and 1800 out of phase with the pulsations of particles with the opposite charge). Since a magnetic force is also involved, it is a complex pulsation, perhaps, with internal cycles in two different planes. The electric and magnetic forces that arise from space to keep its pulsations in synch as the charged particle moves across space are the electric and magnetic forces, which were described by Maxwell. They are the same forces that can be coupled and exist independently as photons (for example, as a result of charged objects oscillating back and forth, as in antennas).

The photon introduces most of the properties that basic objects have, and in order to explain the other basic particles, we must postulate the existence of two other varieties of particles, weakons and neutrinos. All the other particles, both charged leptons and quarks, will be explained as combinations of neutrinos and weakons. The interaction between them is the weak force, on this ontological theory.

Weakons. The nature of weakons can be described in much the same terms that were used to describe the photon above. Weakons are also spin 1 bosons, for they are the gauge particles of the weak force. Given or theory about the nature of quantum matter, we assume that weakons are constituted by cycles of quantum events, and thus, what makes them different from photons is presumably coinciding with space in a different way.

Rest mass. One basic difference between photons and weakons is that weakons have a rest mass, whereas photons are massless. Indeed, weakons have a sizable rest mass, about 80,000 MeV/c2 for the charged weakons and over 90,000 MeV/c2 for the neutral weakon. That is nearly one hundred times the rest mass of the proton.

Rest mass is the property that made it impossible to explain weakons as the gauge particle of the weak field on the model of photons in the electromagnetic field, since gauge bosons are massless, according to Yang-Mills field theory. What makes Yang-Mills field theory so attractive is that particles interact the same way regardless of scale. They are, in other words, “gauge invariant.” But if one simply assumes that gauge particles have a rest mass, then the particles are no longer invariant under a gauge transformation. When the relevant particles are described on a much smaller scale, as if we were looking at them through a microscope, their mass decreases to the vanishing point. Mass in not gauge invariant.

In order to give the gauge particle of the weak field a rest mass, therefore, physicists postulate another kind of particle, the Higgs boson, which is the gauge boson of yet another field. Unlike the weakon and the photon, which have a spin of 1, the Higgs boson has a spin of 0, meaning that it does not line up at all in the magnetic field. But it gives weakons a mass, only if Higgs bosons are located everywhere in space. Thus, it is assumed that the Higgs field is in a condition of least energy when there are Higgs particles everywhere. But the Higgs boson is a force with a certain strength (which enables the weakon to resist acceleration so that it tends to stay at rest), and so that is to say that the Higgs field has least energy when its force is strongest everywhere. This is paradoxical, because the energy associated with every other force of nature increases with the strength of the force.

Notice, however, that although this description of what gives the weakon a rest mass is paradoxical only when it is assumed that it is a description of matter. It is not paradoxical at all as a description of space. Space has no energy (it is not matter), but since it is a substance, it can exert a force. If the weakon’s relationship to space is what gives it a rest mass, it is not surprising that the force is exerted everywhere. Nor is it surprising that that is the condition of least energy, because it does not involve any energy at all. Thus, since we have already postulated the existence of space as a substance for other reasons, we can explain the rest mass of weakons without postulating Higgs bosons. We can take talk of Higgs particles to be a way of referring to space.

The function of the Higgs mechanism can be served by recognizing that quantum cycle have another way of coinciding with space. Instead of being picked up by the inherent motion and laying out their cycles as a certain wavelength in space, the quantum cycles of weakons have a purely rotational motion, and so they can be at rest in space. We assume that when quantum cycles coincide with space at rest, their matter has the form of rest mass, that is, the matter resists acceleration by a force. Weakons can, of course, be accelerated, and their rest mass determines, as we have seen, the scale of the quantum kinetic cycles that move these particles across space as time passes. But that role of rest mass comes from their relationship to space, not to Higgs bosons.

Like photons, weakons are bosons with an intrinsic spin of 1. That means that there are three different ways that a weakon and interact in a magnetic field. That means, as we shall assume, that each and every weakon has all three ways of interacting, and which way they interact depends on how they are oriented in the field. Taken geometrically, each way of interacting in a magnetic field can be pictured as a different face of the particle.

Two of the faces correspond to spin up and spin down, that is, having a positive or negative moment in the magnetic field. Each such face can be represented as a direction of rotation along an axis parallel to the direction of its motion, yielding two possibilities, left-handed spin and right-handed spin, as depicted in the accompanying diagram. These two faces are all that a particle with ½ spin has, and so as a first approximation, it could be represented as rotational quantum cycles of some kind which could be oriented in opposite directions relative to the magnetic field.

A spin 1 particle has a third face by which it can be oriented in a magnetic field in which it has no magnetic moment at all. But in the case of the weakon, we cannot hold that this zero face is lost by moving through space with the inherent motion of space, because weakons can be at rest. Instead, we have to admit that the weakon can interact in a way in which its two faces, with opposite orientations of spin, are somehow perfectly balanced. That suggests that we think of the weakon, not as a rotation which can interact only from either side of its axis, but as a rotating cylinder. If it is oriented so that one end is interacting with the magnetic field, it is rotating in one direction, and if it is turned around so that it interacts from with its opposite side, it is rotating in the opposite direction with a magnetic moment of the opposite sign. But if the cylinder interacts with the magnetic field from its side, it has no net rotation in the magnetic field, and its other faces are balanced against one another. That is how its zero face will be represented geometrically.

Electric charge. There are three kinds of weakons. Two have electric charges, with signs opposite to one another, and the third weakon is neutral. These are different kinds of weakons, not faces of each weakon. But given out assumption about the nature of the electromagnetic field, their charges can be explained as opposite ways of relating to the universal, electromagnetic pulsation, which is mediated by the inherent motion.

The electric charge is what is conserved by virtual photons, as the gauge bosons of the electromagnetic field. Since we are assuming that the forces of an electric charge are exerted in pulses that are perfectly synchronized with similar pulsations by other particles with the same charge wherever they are located in the universe, we can explain why like charges repel. And since opposite charges are 1800 out of phase, particles with opposite charge should attract one another. (We have also assumed that the pulsations have an additional complexity that accounts for the magnetic forces.)

These electromagnetic pulsations are independent of the rotational quantum cycles we have been describing in order to explain the three faces of spin orientation. Their intrinsic spin lines the particles up in a certain way in the magnetic field, but the direction of the electric and magnetic forces they feel depends on the gauge bosons that arise from the electromagnetic field in a way that keeps their pulsations synchronized as they move across space.

[We shall simply assume that weakons can have electric charges (and that they can exist without them), as a basic property of weakons. But there may be a simpler ontological explanation. Since weakons and photons are both constituted by quantum cycles, it is conceivable that the charged weakon is simply a photon at rest, or to take the weakon as basic, that the photon is simply a weakon that is moving across space. Though the weakon may have an electric charge when it is at rest, its zero face (without any magnetic moment) may be engaged with the inherent motion so that moves it across space at the velocity of light. In that case, it loses is rest mass and its electric charge is disengaged from the universal pulsation and becomes an electric force that is exerted in time with the rotations of its intrinsic spin, marking out the wavelengths of light. But when this particle is at rest, its cycles of electric forces are exerted from a point in space, and that geometrical configuration could be the radial field of the electric charge of the weakon, whose pulsations are synchronized with the pulsations of like particles everywhere. This would simplify the ontological explanation of basic particles even further, but I will leave it here as just a possibility.]

Weak charge. The weakon is the gauge particle of the weak force, and though it can act on other weakons, it needs fermions on which to act, and that is the role of neutrinos.

Neutrinos. The other kind of basic particle we must postulate is the neutrino, though as I suggested, it might be just an aspect of space in its interaction with weakons. The neutrino is a fermion, an opposite kind of particle from bosons, because it excludes other particles of the same kind from occupying the same quantum state (including location in space). Its spin of ½ means that it should have two possible orientation by which it can interact in a magnetic field, one face with a positive magnetic moment and another face with a negative magnetic moment.

Fermions can be represented geometrically as a rotational motion of some kind. From one side, a fermion would be rotating in one direction, whereas from the other side, it would be rotating in the opposite direction. There are, however, various kinds of rotation that could constitute a fermion, on this ontological theory, and let me emphasize that, though the frequency of the rotation or circular motion may vary, the magnetic moment is quantized. That is, the strength of the magnetic moment is a fixed quantity that does not depend on how fast it is rotating. That is just how basic particles coincide with space.

Varieties of neutrinos. Neutrinos differ from one another in two ways, by size and spin.

There are three sizes of neutrinos: the electron neutrino, which is the biggest, the muon neutrino, which is smaller, and the tau neutrino, which is the smallest of all three. It is not impossible that there are even smaller neutrinos, and I will suggest how they would be incorporated in this theory later. Furthermore, we shall assume that the spin of the neutrino is more like a motion around a circular pathway than it is the simple rotation of an object, and thus, the size of each kind of neutrino is the size of its circular pathway.

The spin of neutrinos are seen as problematic, because they violate the principle that fermions have two possible orientations by which they can interact in a magnetic field. Neutrinos have only a left-handed spin, that is, they rotate counterclockwise along an axis parallel to the direction of their motion. There are no neutrinos with a right-handed spin. Or at least, the weak force interacts only with left-handed neutrinos. (This is a violation of a symmetry recognized in particles, called “parity,” in which it is required that it also be possible for their structures and interactions to occur as if reflected in a mirror.)

The antineutrino, the antiparticle of the neutrino, however, does have a right-handed spin; that is, it rotates clockwise in the direction of its motion. Thus, for each neutrino, there is an antineutrino of the same size, but with the opposite orientation of spin. What is problematic about the spin of the neutrino is, therefore, that the distinction between being the same particle with the opposite orientation of spin and being the antiparticle breaks down in the case of the neutrino. That may be problematic mathematically, but it is not an ontological problem.

On this theory, neutrinos are special because they are elements that constitute other particles and, thereby, explain their properties, and it would not be surprising if the simplest particles do not have all the properties of the particles they explain. Thus, we will assume that neutrinos, as fermions, have two faces by which they can interact in a magnetic field, but that the opposite orientation of spin is also the antiparticle. Neutrinos have a left-handed spin along an axis parallel to the direction of their motion, whereas those with a right-handed spin are antineutrinos.

The reason the difference in orientation of spin gets confused with the difference between particle and antiparticle is that “antiparticles” is defined in terms of opposite electric charge, or “charge conjugation,” and we shall see how their opposite orientations in spin give neutrinos and antineutrinos different relationships to electric charges.

Relationship to space. Though I am counting neutrinos as basic particles, they will be explained ontologically in a way that may be come down to reducing them to an aspect of space. That is possible, because space is a substance, and its circular motion could be just an additional aspect of the inherent motion. Let us assume, accordingly, that there is at every point in space at least three kinds of motion that travel around in circles. Each goes both ways, and they are found in every plane of three dimensional space. There is a largest size for such circular pathways, which determines the longest period for a complete circuit, and circular pathways with shorter radii have shorter periods, with more complete circuits per second.

The idea is that there exists both a neutrino and antineutrino of all three kinds at every point in space. These circular motions are another aspect of space, like the inherent motion and presumably connected with the inherent motion in some way. Although these pairs of circular pathways do not have any linear motion through space (except for the motion of the inherent motion itself in a gravitational field), they do not have rest mass in space, because they are just parts of space itself.

We assume that there is an angular momentum associated with each circular motion, which would give it a moment of force in a magnetic field (explaining its intrinsic spin). That is to say that these circular pathways are oriented relative to the magnetic field. But since neutrino and antineutrino exist together, their angular momentums cancel out. They are neutralized, because they are circular motions in opposite directions. Thus, these circular pathways in space do not usually have any effect on what happens. Photons pass right through them, as do particles with rest mass, as if there was only space at that location.

This is to explain the neutrino ontologically in an opposite way from weakons. Unlike weakons, which have a rest mass that can be explained ontologically by the quantum cycles per second, neutrinos have no rest mass. At least, nothing in the theory requires them to have a rest, and experiments show that it cannot have more mass than about 12 eV/c2. Thus, they may not even be constituted by quantum cycles, like forms of quantum matter. They could be simply aspects of space, because as we assumed, the magnetic field in which they are oriented is just an aspect of space (a form of force-field matter).

Interaction with weakons. Though neutrinos do not have an electric charge, they do have a weak charge. That is, they interact with weakons. But weakons exist only as pairs with opposite orientations of spin, and thus, we shall assume that the weakon can act on neutrinos by extracting one of these circular pathways from space and using it to travel around in circles. The weakon and the circular pathways are both oriented in the magnetic field, and when the weakon latches onto a such pathway with a circular motion in one direction, and it releases the pathway with opposite circular motion.

Since the released neutrino has no rest mass, it moves away from its former partner at the velocity of light. That is what physics assumes, though we shall explain its motion as due to the inherent motion in space. It engages with the inherent motion and thereby acquires the velocity of light. The released neutrino is just a bit of angular momentum that propagates through space, and it will not interact with anything, unless it runs into a weakon.

Weakons act on neutrino-antineutrino pairs where they are located, but how they act on such a pair depends on the charge of the weakon. A negatively charged weakon extracts a circular pathway with a left-handed circular motion relative to the direction of the magnetic field, and thus, it releases an antineutrino, that is, a neutrino with a right-handed circular motion. Correspondingly, a positively charged weakon extracts a circular pathway with a right-handed circular motion, and since that is an antineutrino, what it releases is a neutrino, which runs off with the inherent motion. The 1800 difference in the phases of pulsations of the positive and negative charges of weakons corresponds, therefore, to the right-handed and left-handed spins of neutrinos.

Charged leptons.This interaction between charged weakons and neutrinos affords an ontological explanation of charged leptons. The member of the neutrino pair that is retained by the weakon is used as a pathway to guide its own motion, transforming the weakon into a charged lepton, such as a tau particle, a muon, or an electron. Let us see how the properties of a charged lepton can be explained by this combination.

Electric charge. The weakon that interacts with the neutrino-antineutrino pair has an electric charge, and since electric charge is conserved, the charge is inherited by the lepton created by this weakon-neutrino interaction.

Negatively charged weakons extract neutrinos from space to use as their new pathway, and thus, negatively charged leptons contain a neutrino and they release an antineutrino. Positively charged weakons, on the other hand, extract an antineutrino for themselves and release the neutrino.

[It would be possible to formulate a theory like this by holding that the weakon simply acquires a new kind angular momentum from space and explaining the antineutrino as simply a form of angular momentum that remains in space as its way of conserving momentum. That might be a simpler theory, which emphasizes that neutrinos are just aspects of space, but it would leave out how space supplies the angular momentum that the lepton acquires as the weakon changes to a fermion. Thus, I will continue to describe the near basic particles as being constituted in part by neutrinos, if only to keep track of what space is contributing to their structures.]

The neutral weakon, Z0, does not interact with neutrino-antineutrino pairs at all. It mediates purely elastic collisions among particles with a weak charge. The electromagnetic pulsation of the electric charge is presumably what engages with space to extract neutrinos from them (suggesting that the circular motion of the neutrino and antineutrino is synchronized with the universal pulsation of negative and positive charges, respectively).

Rest mass. Let us assume that the weakon interacts with the neutrino from its neutral face, that is, from the side of the cylindrical boson. Such a geometrical relationship is possible, since both particles are assumed to be lined up with the magnetic field. We have assumed that the cylinder is rotating, presumably with each rotation being a quantum cycle, so that the frequency of its quantum cycles explains its rest mass. It has a large rest mass, but if we assume that, when it interacts with a neutrino, its own rotation becomes a circular motion along the neutrino pathway, we can explain why the charged lepton has less rest mass than the weakon.

Since each circuit around such a circular pathway would take longer than one of the simple rotations that constitute the rest mass of the weakon, there are fewer quantum cycles per second in the new lepton, giving the composite particle a lower rest mass. But matter is conserved. The quantum cycles that previously constituted the rest mass of the weakon do not drop out of existence, but rather are converted into quantum kinetic cycles, which give the new particle with a smaller rest mass a velocity relative to the inherent motion. (Momentum is conserved, because the antineutrino that takes off some direction in space with the inherent motion has an equal and opposite momentum.)

There are, however, at least three different sizes of circular pathways in space, and the smaller the circular pathway, the shorter the period and the greater the rest mass. Since a weakon has an enormous mass, it would usually become a tau particle or a muon before it became an electron. When a negatively charged weakon extracts a tau neutrino from space, for example, it releases a tau antineutrino. But since the muon and electron have longer pathways, requiring fewer quantum cycles per second, the tau particle can decay further. What remains of the negative weakon in the tau particle will release its tau neutrino, extract, say, a muon neutrino from space and release a muon antineutrino (with surplus matter converted to kinetic energy). Likewise, the muon would decay into an electron by releasing its muon neutrino, extracting an electron neutrino from space, and releasing the electron antineutrino to run off with the inherent motion. The electron is the last step, because it is the largest circular pathway possible in space, requiring the fewest quantum cycles per second. These are the decay patterns of weakons and charged leptons that have been found by physics, though they are explained here ontologically, by the size of the circular pathways provided by the neutrinos.

Spin. Intrinsic spin angular momentum is also conserved in the creation of a charged lepton, though in a curious way that might explain a couple of otherwise puzzling fact about leptons. The neutrino has no rest mass of its own, but when it is used as a pathway by a weakon, the composite particle acquires rest mass, which enables the lepton to be at rest in space. Thus, though free neutrinos lose one of their faces to the inherent motion, the captured neutrino can give the lepton it helps constitute a spin of 1/2 , with two faces from which it can interact in a magnetic field. With a weakon on its circular pathway, it has a rest mass and can turn around. Thus, it can be oriented in either way in a magnetic field. In one case, it will have a left-handed spin along an axis parallel to its motion in the magnetic field, and in the other case it will have a right-handed spin.

If the spin of the charged lepton comes from the neutrino, however, what happens to the other two faces of spin of the weakon? We have explained what happened to its neutral face. That is the face that the weakon uses to travel around the circular pathway (much as the photon uses its neutral face to travel along with the inherent motion). But the weakon had two other faces, one that give it a positive moment in a magnetic field and another that would give it a negative moment. These are represented by the two ends of the cylindrical structure of the spin one boson. The question is what happens to them.

Geometrically, the simplest explanation is that each of the weakon’s two non-zero faces coincides with one face of the neutrino in constituting the charged lepton. The circular pathway gives the charged lepton two opposite ways of being oriented in a magnetic field, because one of the non-zero faces of the weakon coincides with one face of the neutrino, and the other non-zero face coincides with the other one face of the neutrino.

To be sure, we have assumed that following the neutrino pathway requires the weakon to have fewer quantum cycles pre second, lowering its rest mass. It is as if the rotation of the cylindrical weakon were slowed down so that the weakon could follow the circular pathway provided by the neutrino. But the decrease in quantum cycles per second does not mean that its spin angular momentum is changed, because we are assuming that spin angular momentum is quantized. That is, the magnetic moment due to intrinsic spin is an all or nothing property: either the particle has it or not. Thus, the particle would have that same quantum property regardless of the frequency of the quantum rest mass cycles constituting it.

It may seem redundant or even gratuitous to suppose that the two non-zero faces of the weakon coincide with the two faces of the lepton. But it would explain one or two otherwise puzzling facts about leptons.

First, we know from Dirac’s equations that charged leptons, such as the electron, cannot be turned over completely by rotating them 3600, as one would expect, but requires two full turns. Since a 1800 rotation would make the face with the opposite orientation of spin in front, one would expect that two 1800 rotations would turn it back to its original state. Though a 1800 does give it the opposite orientation of spin, the equations imply that the electron has returned completely to its original size until it has been turned over twice, that is, 7200. That otherwise curious feature of the charged lepton would be explained ontologically on this theory, because turning it over completely would involve turning over not only the two opposite faces that the charged lepton derives from the neutrino’s circular pathway, but also the two opposite, non-zero faces that it derives from the weakon that is using that circular pathway.

Second, this ontological explanation of the charged lepton might explain another puzzling property. The electron has a spin of ½, as if its spin were only one-half of a quantum of action, and yet the magnetic moment that it exhibits in a magnetic field is more like what it would have, if it were a complete quantum of action, that is, about twice the expected strength. That could be explained, perhaps, by the way in which the spin of the charged lepton derives from the non-zero faces of the weakon. With a spin of 1, the weakon has a stronger moment in a magnetic field, when it has one at all, and that could be the source of the magnetic force of the charged lepton. This would be to interpret the “½” as just a device for cataloguing basic objects by the number of faces they can show for interaction in a magnetic field. (That is, according to quantum mechanics, the strength of the magnetic moment is the square root of the product of the spin and the spin-plus-one, or (s(s + 1))1/2, and that means that the non-zero faces of the weakon have a magnetic moment equal to the square root of two times Planck’s constant, whereas the spin ½ particles has a magnetic moment equal to the square root of three divided by two times Planck’s constant.)

Decay patterns. As we have seen, this ontological explanation explains the decay patterns of the negatively charged weakon into the tau particle, muons and electron. It remains only to point out that it also explains the decay patterns of the positively charged weakon, and why decay stops there.

The positively charged weakon, W+, interacts in a magnetic field with the neutrino-antineutrino pairs in space, but it latches onto the circular pathway with a right-handed spin in the magnetic field, or the antineutrino, and it releases the neutrino, with a left-handed spin. Otherwise, the decay pattern is the same as described above, because the tau neutrino is the smallest, followed by the muon neutrino and, finally, the electron neutrino. The rest masses of the resulting positively charged leptons is inversely related to the sizes of their neutrino pathways.

The electron (or positron) is a stable particle, because it carries an electric charge, which cannot come apart, and there are no larger pathways in space than those provided by the electron neutrino (or antineutrino). We must take the conservation of electric charge to be a fact about how matter coincides with space, an aspect of the electromagnetic field whose gauge bosons exert forces that keep its pulsations in phase with other charged particles throughout the universe, on this interpretation of gauge field theories.

Quarks. Quarks cannot be explained in the same way as charged leptons, because weakons do not decay into quarks. Indeed, quarks are never found in isolation from one another. Hence, baryons, at least, must have existed from the beginning of the universe (or forever). But quarks can still be given a genuine ontological explanation in terms of the simpler particles of which they are composed, for their constitution could explain their properties and decay patterns. Though that would mean that quarks are not basic particles, the special configuration of more basic particles constituting them must have existed from the beginning, and that would be an ontological explanation of them. That is what is proposed here.

By contrast, attempts by physicists to explain quarks by a more basic structure focus on formulating a mathematical law from which both the electroweak force and the strong (i.e., color) force can be derived. This is the attempt to discover what is called the “grand unified theory,” or GUT, and though it is successful in some ways, it implies that there is a magnetic monopole and that the proton can decay. Neither phenomenon has been observed, and on this ontological theory, neither is possible. (Instead, the magnetic field is an aspect of space connected with the inherent motion by which particles are lined up according to their spin orientation to interact with one another, the protons may have a geometrical structure in space that literally cannot be undone.)

Quantum matter. The main idea of this theory of quantum matter is that bits of matter are constituted by cycles of quantum events in such a way that the quantity of matter in any object is equal to the total number of its quantum cycles per second. Such a nature is plain enough in the photon, whose motion across space with the inherent motion marks out its wavelength. And it has revealing implications in the case of the quantum kinetic cycles, which constitute the kinetic energy of particles with rest mass. But this nature is not so clear in the case of the particles with rest mass themselves, because their quantum cycles must somehow be contained by space in a way that does not involve motion relative to the inherent motion in space.

Weakons are a most elementary from of quantum matter, and so we have assumed that the weakon manages this trick by simply rotating like a cylinder, though, of course, with a fixed and unchanging number of quantum cycles per second (about 1024 cycles per second, given its rest mass of 80,000 MeV/c2 and a photon with an energy on the order of a few electron volts having a frequency of about 1015).

We have seen how charged leptons could be constituted by quantum cycles in which the weakon’s unit of action completes a circuit provided by a neutrino’s circular pathway. Each circuit takes so much longer than a simple rotation around it own axis that it reduces the total number of quantum cycles required each second to constitute the continued existence of the particle.

Quarks can also be explained as being constituted by a pathway for quantum cycles of the kind that derive from weakons. But the pathway must be more complex than leptons. The simplest way to explain why quarks cannot exist apart from one another is to hold that the pathway followed by their constituent quantum cycles depends on a combination of quarks. This is plausible, because physics has discovered that three quarks are required to make up a baryon, the only stable hadron, and each meson, the particle that mediates the strong force between them, is made up of a quark and an antiquark. As it happens, there is a way to explain these particles, their properties and decay patterns along the lines of the foregoing ontological explanation of charged leptons.

Twisted circular pathways. The key to the ontological explanation of quarks is, once again, the interaction between weakons and neutrinos. This is to interpret the weak force, not merely as the cause of decay patterns, but as the force that is responsible for their constitution. The weak force gives particles a nature by binding weakons to neutrinos. I have been describing this bond as a weakon moving along a pathway provided by a neutrino, and that is still the best way to represent it geometrically in the case of quarks. But even a single quark involves a more complex interaction between weakons and neutrinos than is found in charged leptons.

We must assume that the weak force can interact with two neutrinos. Such interactions are possible only when the neutrinos are of different sizes and one is a neutrino, while the other is an antineutrino. Moreover, it is an ordered interaction in which the two neutrinos play different roles. One neutrino is dominant, and the other neutrino is partially hidden. Such an interaction is what constitutes a single quark.

The interaction in a quark can be pictured in terms of a pathway provided for the weakon by the two neutrinos. What happens as the weakon moves along that pathway is that the weakon starts off moving around a circle in one plane, just as in a charged lepton, but the effect of the other neutrino is that the weakon winds up moving circularly in an orthogonal plane. That is, during each quantum event, the weakon follows a circular motion that is also twisted so that the plane of circular motion rotates 900. That is not by itself a closed pathway for the weakon, but there are two different ways that the pathway can be closed — by the combination of quarks in mesons and baryons.

First, the weakon coming out of the twisted circular pathway one quark can enter the twisted pathway of an antiquark, and since the second quark rotates the plane of circular motion back to the initial plane of the first quark, the weakon can go around again and again. The second quark is able to complete the closed pathway because it is the mirror image of the first quark. That is the basic pattern of the meson. But notice that two weakons are required to constitute a meson. The complete pathway involves both a quark and an antiquark, and a complete quantum event is required for the weakon to traverse the pathway of each twisted circle.

Second, it is also possible to put three of these twisting circles together as a closed pathway. In the first quark, the weakon follows a circular pathway which twists into a circular pathway in an orthogonal plane, and the second quark picks up the circular motion in that plane and twists it into a circular motion to the remaining plane which is orthogonal to both in three dimensional space. That is still not a closed pathway, but with a third quark that picks up the circular motion in that third plane and rotates it back to initial plane of circular motion in the first quark, the weakon can repeat the same trip over and over again. Since each twisting circle comes out in a direction perpendicular to its entrance, three of them together brings the weakon back to its starting point. This is the plan followed in baryons, composed of three quarks each. But three weakons are required to constitute such a particle, because one must be traversing each twisted circular pathways during each cycle. That is, three parallel series of quantum cycles constitute each baryon.

Weak interaction in each quark. This weak interaction in a quark between weakons and two neutrinos must, of course, be assumed as part of the nature of the weak force. It is a single quantum event, but it can be pictured in much the same way we did in the case of leptons.

Instead of interacting with the neutrinos by its zero face, the weakon could interact with both neutrinos at once, if it interacted by way of its two non-zero faces, each with an opposite orientation of spin in a magnetic field. That is, one non-zero face would try to follow the circular pathway of the neutrino, while the other non-zero face would try to follow the circular pathway provided by the antineutrino, and the combination of these two influences would result in a twisted circular pathway that rotates from one plane in three dimensional space to another.

This pattern would explain why the quark is constituted by a neutrino and an antineutrino, rather than two neutrinos (of different sizes). Since the non-zero faces of the weakon have opposite orientations of spin, the neutrinos with which they interact also have opposite orientations of spin.

A weakon interacting with a neutrino and antineutrino in this way would be contorted in a way that leaves its zero-face free, and that could become the face by which each quark exerts color forces on other quarks and passes its weakon on to the next quark. The eight different gluons might then be explained geometrically as the forces needed to line up three quarks properly (or to line a quark and antiquark) so that the weakon can complete a full circuit through them. Each quark must pick up a circular motion in one plane, twist it to another plane, and pass the circular motion onto another quark, and the gluons could be explained geometrically by their various roles in giving the three quarks the constant spatial relationship required for the weakons to make a complete their trips through the quarks. In other words, the color force would be another aspect of the weak force that is manifested when weakons interact with these neutrino-antineutrino combinations.

Notice that this account of the interaction between neutrinos and weakons parallels the explanation of leptons, for in that case, the interaction of the zero-face of the weakon with a neutrino exposed the two non-zero faces of the weakon, explaining the two non-zero faces of the charged lepton entailed by its ½ spin as a fermion.

[There may be other ways of picturing this interaction geometrically, though their explanations do not seem to be as complete. If the weakon uses its zero face, perhaps it begins in each quark by following the pathway of one neutrino, but in the presence of an antineutrino of a different size, it simply shifts to the second pathway, which twists its circular pathway. However, the quark seems to be a point-like object, and this theory does not explain its unity, since a sequential pathway would seem to require two quantum events. Furthermore, it does not explain why the interaction does not occur with two neutrinos of different sizes. Why is an antineutrino involved. (Notice that on the previous model, there is are reason for having both a neutrino and an antineutrino. Nor does it have any problem explaining why the neutrino and antineutrino are not of the same size, since a neutrino and antineutrino of the same size would annihilate one another.]

Kinds of quarks. If quarks are constituted by neutrinos and weakons in some such way, it is possible to explain all the kinds of quarks by the kinds of neutrinos of which they are composed. There are just enough differences between the composite particles to explain all the properties that distinguish one kind of quark from another, including their antiquarks.

Spin. As fermions, all the quarks have a spin of ½. We assume that the interaction between weakons and a neutrino and antineutrino of different sizes in each quark is a single quantum event. Together these more basic particles must make up a single fermion. As long as each weak interaction is a single quantum event, it is not impossible for a particle constituted this way to have a spin of ½, because the spins of the constituent neutrinos are not oriented in the same plane, where their spins would cancel one another out. Instead, the neutrinos are bound to one another in a way that we are assuming is unequal. One of the neutrinos making up the quark is dominant, as if the other neutrino were somehow hidden, and thus, the dominant neutrino’s orientation of spin can be assumed to be what gives the quark as a whole the two, opposite faces that fermions, with a spin of ½, must have.

There is one set of combinations of neutrinos with weakons that will explain all the kinds of quarks and their properties. Those combinations are indicated in the accompanying diagram (Constitution of Quarks). In each case, the first neutrino (or antineutrino) in each stack is the dominant one, tending to mask the other neutrino (or antineutrino).

Sign of electric charge. The d, s and b quarks all have an electric charge of –1/3, whereas the u, c and t quarks all have a charge of +2/3. And antiparticles always have the opposite electric charge. The sign of the charge of the quark depends on the dominant neutrino in the same way that the sign of the charged lepton is determined. We assumed that the spin of the neutrino is synchronized with the universal pulsation of negatively charged particles and that the spin of the antineutrino is synchronized with the positive pulsation. That is how we explained why neutrinos acquire a negative charge, and antineutrinos acquire a positive charge. Accordingly, the charge of the quark is negative, when its dominant member is a neutrino, and the quark’s charge is positive, when the dominant member is an antineutrino (whatever ultimately explains the “dominance” of one neutrino over another in a quark).

Size of electric charge. The electric charge of the quark is either 1/3 or 2/3, and that can be explained as a result of the combination of the two neutrinos. We are assuming that the charge is a pulse of electric force that is synchronized with the universal pulsation of such charges, and thus, since negative and positive charges are 1800 out of phase with one another, the fractional charges can be explained by an appropriate rotation or phase shift in the cycle of such pulsations. It is presumably because a neutrino and antineutrino have opposite phases relative to that universal pulsation that the electric charge of the quark is in between –1 and +1, and so the relative sizes of the dominant and hidden neutrino could determine the size of the quark’s charge. That is, if the dominant neutrino is bigger (requiring fewer quantum cycles per second if it were on its own), then it is a charge of 1/3. But if the dominant neutrino is smaller (requiring more quantum cycles per second on its own), the charge is 2/3.

If the conservation of electric charge is due to the electromagnetic field, it is possible for the weakon traversing one of these twisted pathways to be separated from the electric charge it has when its exists independently, and it could even be what actually keeps the weak force from acting in ways that would not conserve charge (though there is probably a deeper explanation).

Rest mass. The rest masses of quarks are not well defined, because the quantities are not entailed by theory and the quarks cannot be measured apart from the baryons or weakons. It appears, however, that a good part of the rest mass of the baryon and meson comes from the gluons by which weakons pass from one quark to another, and since that matter presumably exist as potential and kinetic energy, the quarks are probably somehow in motion as the weakons are passing through them. Experiments do, however, suggest a range of rest masses for the quarks themselves, and the differences among them can be explained according to the theory of quantum matter.

The second family of quarks is more massive than the first, and the third family is more massive than the second. Moreover, in the second and third families, the quarks with 2/3 charge are considerably more massive than the quarks with 1/3 charge. These differences can be explained on the assumption that the rest mass depends on the total number of quantum cycles per second, because neutrinos with smaller circular pathways require more quantum cycles per second. Thus, the greater mass of later families can be explained by their use of smaller neutrinos: the tau neutrino replaces the muon neutrino in the second family and the muon neutrino replaces the electron neutrino in the third family. And the greater mass of the quark with 2/3 charge in the second and third families can be explained by the smaller size of the dominant neutrino.

Decay patterns of hadrons. The decay patterns of both baryons and meson can be explained by this theory of quarks. In a weak decay, one kind of quark turns into another kind, and this can happen in two ways. Either the dominant and hidden neutrinos switch roles, or they switch roles and one of the neutrinos is replaced by a larger neutrino (requiring fewer quantum cycles).

One pattern is the decay that occurs within each family of quarks. When a neutron decays into a proton, for example, the triplet of ddu quarks becomes a triplet of duu quarks, giving off an electron and an electron antineutrino (which is thought to be mediated by the decay of the negative virtual weakon released in the process). On this theory of quarks, what happens is that a d quark becomes a u quark, and that means that their neutrinos change positions. The muon antineutrino, which was the hidden member in the d quark, becomes the dominant member of the u quark, and the electron neutrino of the d quark becomes the masked member of the u quark. T

The same pattern occurs in the decay of mesons, which mediate the strong force among hadrons. For example, the negative pion is made up of a d quark and a u antiquark, and it typically decays into a negative muon and a muon antineutrino (by way of a negative virtual weakon). One of the ways this could happen is that the u antiquark becomes a d antiquark. That means that the electron antineutrino and the muon neutrino switch roles, and since that leaves the electron neutrino facing the electron antineutrino and the muon neutrino facing the muon antineutrino, they annihilate one another, and the weakon extracts a muon neutrino from space to become a lepton leaving a muon antineutrino as debris.

The weakon is just a virtual particle in these interactions. It is the gauge boson that arises from the weak field, that is, from space, according to the gauge field theory, to preserve the weak charges of the particles. For that role, the weakon does not need to have the energy of an independently existing weakon (any more than the virtual photon that mediates the electric and magnetic forces among electrically charged particles needs to have the energy of an independently existing photon). On this explanation, however, it is the weak charges of the neutrinos that are be preserved, and their weak charges are preserved by forces that line the neutrinos up as parts of the quark. Thus, the weak force can change the dominance roles of neutrinos in a quark (as long as electric charge is conserved). And any matter left over can act like a charged weakon on space to extract a neutrino and become a charged lepton (leaving the antineutrino as debris).

The other pattern is the decay that occurs between families of quarks. The sigma minus is a baryon composed of the quark triplet, dds, and it typically decays into a neutron, with ddu, and a negative pion, which carries away the negative charge (and decays as described above). The decay of sigma minus requires an s quark to become a u quark. That involves not only a reversal of the roles of the two neutrinos in the s quark, so that the electron neutrino shifts from the dominant position in the s quark to the hidden position in the u quark, but also a replacement of the tau antineutrino in the s quark by a muon antineutrino as it takes up the dominant position in the u quark. Thus, this theory would imply that the decay of the sigma minus leaves two neutrinos in addition to the negative pion which is recognized, namely, the tau antineutrino that is released from the decay of the s quark and the muon neutrino that was also extracted from space in order to supply a muon antineutrino for the dominant position.

This other pattern also occurs in mesons. The positive kaon, for example, is a meson composed of a u quark and as s antiquark, and it typically decays into a positive muon and muon neutrino. Assuming that the neutrinos and antineutrinos must be lined up to annihilate one another, this requires the s antiquark to decay into a u antiquark, for then it can annihilate the u quark. That requires that the neutrinos in the s antiquark to switch roles and at the same time replace the tau neutrino with a muon neutrino (that is, the electron antineutrino gives up its dominant position in the s antiquark and takes up the hidden position in the u antiquark, and the tau neutrino from the hidden role in the s antiquark is replaced by the muon neutrino in taking up the dominant position in the u quark), Again there are two neutrinos as extra debris, because the s quark must not only release its tau antineutrino, but also extract a muon antineutrino in its place, releasing a muon neutrino.

All of the decays of quarks between families of quarks involve such additional neutrino debris, which are not recognized by high energy physics. But that is not an empirical reason for doubting that this theory is true, because neutrinos interact so weakly that they are almost impossible to detect. They cannot be monitored in particle accelerators. And this theory about the nature of quarks is not held by physicists.

Other families of leptons and quarks. It is possible, given this ontological explanation, that there are additional families of charged leptons and quarks. It would require a smaller neutrino and antineutrino. Call it “x”.

Charged leptons could be constituted by them and charged weakons in the same way as the electron, muon and tau particle (and their antiparticle). Their smaller size would require more quantum cycles per second, and that may be the reason they have not been observed, if they exist at all.

Given the role of neutrinos in constituting quarks, such a smaller neutrino would mean that there could be three more families of quarks. Consider the families of quarks with negative 1/3 charge, the d, s, and b quarks. Following their pattern, there could be such a quark composed of an electron neutrino and the x antineutrino, a muon and x antineutrino, and one with a tau particle and an x antineutrino. Similarly for the other members of each current family, there would be three new kinds of quarks, which could constitute baryons and mesons in the same way as currently recognized quarks.

The rules for constituting charged leptons and quarks make it possible to describe yet further families, if there are yet smaller neutrinos.

Permanence of the proton. Contrary to theories currently circulating about the deeper structure of the basic particles of physics, this ontological explanation of their constitution by weakons and neutrinos implies that the proton never decays. That is the other side of the assumption that baryons must have been part of the universe from the beginning. Though their constitution can be explained, they cannot be taken apart.

The structure of the baryon has been explained by holding that quarks have a structure that rotates a circular pathway in one plane of three dimensional space to another plane. Thus, three quarks rotate circular pathways through all three independent planes of three dimensional space in order to provide a complete pathway for weakons. This suggest that the pathway of weakons in the proton is a knot in three dimensional space that cannot be untied. (This model was suggested by P. W. Atkins, 1981., p. 86.) There are two such knots, and since they are mirror images of one another, they would correspond to the difference between baryons and antibaryons.

If, therefore, quarks can be explained by neutrinos and weakons in some such way, then given what has been said about the charged leptons, all the ordinary objects in space are explained ontologically. Physics recognizes 38 different basic particles, and we have seen how spatiomaterialism might make it possible to postulate only 10. It can explain the structure of ordinary material objects by starting with nothing but the photon, three kinds of weakons, and six kinds of neutrinos (three neutrinos and three antineutrinos). And as we have seen, the photon may be simply another form of the charged weakon, while the neutrinos may be just aspects of space that have to do with how space interacts with weakons. It may be possible to explain everything in the world by postulating nothing but space and three kinds of weakons. All the rest could be just how they work together to constitute the natural world.

Whatever the total number of basic particles that must be postulated, this ontological explanation of the basic objects of physics avoids having to believe that everywhere in the vacuum there are particles of every kind and their antiparticles. It is true that an energetic enough photon to create any particle and its antiparticle “out of the vacuum,” as they say. But it is not necessary to believe that all the various kinds of particles recognized by physics are contained everywhere in the vacuum, because if the vacuum is substantival space and it provides the neutrino and antineutrino pairs, all the different kinds of particles can be created together with their antiparticles from them and weakons, wherever there is enough energy.

To be sure, this ontological theory is speculative, and much more would have to be said to defend this theory of basic objects in detail. But the project of ontological philosophy would not be sunk, if this explanation of the basic particles of physics is not correct, because it is not necessary to give such an ontological in order to believe that the world is constituted by space and matter as substances enduring through time. I have included it, because it shows the power of spatiomaterialism to reorient our ways of thinking about physics and to open up new, more promising avenues of thought.

This covers all the basic issue of physics concerning the extreme of the very small and the brief, leaving only the extreme of the very large and long-lasting. In the same speculative spirit, let me suggest what this ontological explanation of the truth of the laws of contemporary implies about the beginning of the beginning, large scale structure, and end of the universe.

Cosmogony. Contemporary cosmology may seem to pose a more serious challenge to spatiomaterialism than current theories about the basic particles. The prevailing belief is that the universe began with a big bang and has been expanding ever since, and if that is true, spatiomaterialism false. Indeed, if that is true, it is not possible to explain the natural world ontologically. There can be no such explanation in a world that begins with the big bang. (For a recent account of modern cosmological theories, see Hawley, 1998.)

Big bang cosmogony. According to the big bang theory, space and matter came into existence at some finite time in the past. (One group holds that it was about 20 billion years ago, and another group holds that it was closer to 10 billion years ago). Before that, there was nothing. No space. No matter. Not even time. At that first moment in time, matter is supposed to exist in a highly energetic state, something like a radiation field with very high energy photons (called gamma rays), and the pressure of this radiation is supposed to cause the expansion. The big bang might be likened to an explosion, except there was, of course, no space for it to expand into. Rather space came into existence with the expansion. That is when time began. Indeed, the theory assume that what exists besides energy is spacetime, not space, and thus, that spacetime was at the beginning tightly curved. The intense radiation field would include all the forces of nature, including the Higgs field, and the energy of those fields, being equivalent to mass, is supposed to have given rise to all the kind of basic particles. The big bang and the subsequent expansion of space is just the increase from zero in the separation of basic objects in spacetime, and since it is the expansion of spacetime itself, and not an event in spacetime, the expansion can be faster than the speed of light in space.

As spacetime itself expanded, the temperature fell. At some point (between 10 and 100 billion degrees Kelvin), the temperature fell far enough for nucleons that had been used into the simplest nuclei to be stable. They were the nuclei of helium (with two protons and two neutrons each), deuterium (an isotope of hydrogen, with both a proton and a neutron), and a few other simple nuclei (such as helium-3 and lithium).

As space expanded further, there was a time about 100,000 years after the big bang when electrons coupled with protons and other nuclei to form atoms. As a result, photons could travel long distances through space without interacting with charged particles.

Subsequent expansion of space led somehow to the formation of galaxies of stars. Indeed, what formed were not only galaxies, but also clusters of galaxies and superclusters of galaxies. It is not at clear how this would happen, or even how stars would form, because when matter is distributed evenly throughout space, there are no net gravitational forces. Presumably, there was an uneven distribution of matter in space, but its origin is still obscure.

The expansion of the universe continues to this day, though it is assumed that the expansion is being slowed down by the gravitational attraction among bits of matter throughout the universe. One of the unresolved issues is whether there is enough matter in the universe to bring its expansion to a halt at the end of time, as most cosmologists would like to believe. A greater quantity of matter would stop the expansion in a finite period of time, causing a contraction which would draw all the matter in the universe (and presumably spacetime) itself back towards a gigantic collapse. But it now appears that the amount of matter (per unit volume) detected in the universe is only about 5 to 10% of what would be needed to stop the expansion, which would force cosmologists to believe that the universe will expand forever.

There is a variant of the big bang theory, the so-called “inflationary” view, due to Alan Guth, which holds that there was a period of very rapid, accelerating expansion very early on (10-33 seconds after the big bang). In one billionth the time it takes light to cross the diameter of an atomic nucleus, there was a huge expansion, increasing distances in space on the order of 1050 times. This would transform submicroscopic distances into cosmic distances, and the reason for this late addition to the big bang theory is that it would explain why the temperature of the universe is the same no matter how far we look in any direction from earth. Without this early inflation, the big bang would have results in a very lumpy universe. But it implies that the universe is much larger than the visible universe, though still finite.

Incompatibility of spatiomaterialism with big bang cosmogony. The big bang theory is incompatible with spatiomaterialism for two reasons, one because it contradicts its assumption about the infinity of time and the other because it contradicts its assumption about the nature of space. .

Time. Part of what makes spatiomaterialism the best ontological explanation of the world is its assumption that existence itself is in time. That assumption about the nature of existence and time entails a certain interpretation of ontological explanation, for an ontological explanation of the world explains everything in the world and everything about the world by showing how it is constituted by substances, and to hold that existence is in time is to hold that the substances used as ontological causes endure through time. If substances never come into existence nor ever go out of existence, any world constituted by them will be temporally infinite in extent.

This is admittedly not the only way of taking ontology to be explanatory. We have acknowledged that it is possible to hold that time is just an aspect of what exists. That is what Einsteinians who take spacetime to be a substances assume about the ultimate nature of the world. Spatiotemporalism, as I called the Einsteinian ontology, is compatible with the belief that the universe had a beginning in time, for it implies merely that there is a limit to the temporal extent of spacetime as a substance that is not itself in time. That makes it possible for cosmologists to accept the big bang explanation of the origin of the world.

The same difference between substantivalism about space and substantivalism about spacetime arises concerning the end of the world. It is possible, according to the big bang theory that the universe might stop expanding and collapse back on itself, and some cosmologists hold that such an outcome would mean that time comes to an end. That would make time finite in the direction of the future as well as toward the past. Such a belief is compatible with Einsteinian ontology, because it would merely mean that the temporal dimension of spacetime as a substance comes to an end in both directions.

There is, however, no way to reconcile spatiomaterialism with either a beginning or an end to the universe it time, because in either case, it would be to give up its view about the nature of existence and time and, thereby, the kind of ontological explanation it gives. To be sure, it is possible for ontologists to hold that existence is in time and to believe the universe had a beginning. That is the view that theists hold. The big bang could be just the way in which God created the world, and the need for such an explanation of the big bang explains why the Pope authorized discussion of the big bang theory so early in its career. But theism gives up naturalism, which is the first of our basic assumption. Any God who could create the natural world would have to be outside space and time and, thus, not something that naturalism can accept.

Space. The other reason that spatiomaterialism cannot accept the big bang explanation of the origin and development of the universe is what it believes about space, and two aspects of its assumptions are at stake. One is its theoretical preference for believing that space is infinite, and the other is its basic assumption that space is a substance.

Infinity. Ontologists would prefer to believe that space is infinite in extent, as well as in its divisibility, because that is the simplest theory. The essential nature of each part of space can be defined as having three-dimensional geometrical relations to every other part of space, for each part would have such relations to a different, ordered set of other parts of space. But if space is finite, each part must have a different essential nature, because each part will have a different spatial relation to the edge of space. And that is not to mention the problem in explaining how space could have an end.

If space is infinite in extent, it is hard to see how space could expand, because there would be, so to speak, no room for more space. All the places in space would already exist. How could ontologists make any sense of the notion?

Cosmologists assume that they can take space to be finite in extent without encountering any problems about the end of space by holding that spacetime throughout the universe is curved. If spacetime contains enough matter, then Einstein’s general theory of relativity implies that a spacetime universe will curve back on itself. If we use two-dimensional space to represent three-dimensional space, then this possibility is supposed to be modeled by the geometry of the surface of a sphere (or Riemannian geometry). But that is not a possible form of spatiomaterialism, because spatiomaterialism replaces the belief in curved spacetime with the belief in the acceleration of the inherent motion in absolute, three dimensional space. Apart from Einstein’s general theory of relativity, there is no reason to believe that space is curved. Indeed, there is no reason to believe that curved space is even possible, if space is a substance. The ability to construct a formal axiom system for curved space does not show that it is ontologically possible.

Substantivalism. Though it is possible for space to be finite in extend in a spatiomaterial world, it is not possible for space to expand. To be sure, if space were finite, the lack of room for the expansion of space would not be a problem. But there would still be an insuperable ontological objection to assuming that it expands, because if space is a substance, the expansion of space would be just another way for something to come from nothing. The measure of space is the distance between parts of space in three dimensions, and if distances were actually increasing, there would have to be more spatial substance separating the points.

Since the big bang theory contradicts spatiomaterialism, it is relevant for ontological philosophy to consider the reasons for believing in the big bang, for they may provide reasons for doubting that spatiomaterialism can be used to do philosophy in this new way. There are two kinds of reasons for believing in big bang cosmogony and the subsequent expansion of the universe, one theoretical and the other empirical, and as we shall see, neither is a good reason for doubting that this is a spatiomaterial world.

Theoretical foundation of big bang cosmogony.The theory behind big bang cosmogony is Einstein’s general theory of relativity. In 1917, shortly after completing his general theory of relativity and before Hubble had discovered evidence of the expansion of the universe, Einstein himself turned his attention to cosmology. Einstein used the basic equation of his general theory of relativity to represent the entire universe, assuming, in effect, that the universe contains a finite quantity of mass and is finite in extent. A finite universe was not implausible to Einstein, because he believed in spacetime, rather than space enduring through time, and a finite spacetime universe can contain enough mass and energy for spacetime to curve back on itself, giving the universe as a whole a spherical geometry. There would be no edges of space to explain, because traveling far enough in any direction would bring one back to where one started.

Einstein soon discovered, however, that even in a universe with spherical geometry, gravitation, being a universal attractive force, would quickly lead to the collapse of the universe. The tendency toward gravitational collapse is even greater than in the Newtonian counterpart of Einstein’s way of representing the universe (which takes the universe to be a finite sphere of material objects in infinite space all attracting one another). On its own, Einstein’s universe would crash in on itself in about the time required for light to cross the universe.

In order to keep his equation from predicting the collapse of the universe, Einstein introduced the so-called “cosmological constant.” It was a perfectly legitimate move, because it was a constant of integration. That is, his general relativity equation had to be integrated in order to represent the universe, and Einstein initially set the constant of integration as zero.

The left side of Einstein’s equation in the general theory is a differential equation that represents the metric of curved spacetime, while the right side of his equation represents the presence of mass and energy in spacetime. To set the constant of integration on the right side equal to zero was to assume, in effect, that the force of gravitation falls to zero at great distances. That is what led to the problem of collapse of the universe.

It was also possible to set the constant of integration at something other than zero. That would represent a repulsive force between material objects at great distances from one another. It would be a very small force at short range, such as the solar system, but the repulsive force would increase with distance. Hence, it would be the dominant force at large scales, and his general relativity equation would no longer predict the collapse of the universe. This was the origin of the cosmological constant. It suggested that there is a form of negative energy associated with the vacuum, and it could make the universe static by canceling out the gravitational attraction at great distances.

The cosmological constant was destined, however,, however, to be rejected, because it implied that the universe is unstable. Though it could be used to represent a static state in which gravitation and long-range repulsion are equal, it was inevitably a precarious balance. The problem is that gravitation falls off with the square of distance, while the repulsive force represented by the cosmological constant increases linearly with distance. Thus, a slight contraction in the universe would make the gravitational force stronger than the repulsive force could resist and the universe would collapse. On the other hand, a slight expansion of the universe would make the repulsive force stronger than gravitation, and the universe would expand faster and faster. In either case, it was not likely to remain the same size.

When Edwin Hubble’s evidence for the expansion of the universe became known in 1929, it seemed that Einstein’s mistake was the attempt to represent the universe as static. If the universe is expanding, the size of the universe must be a dynamic phenomenon. Since his equations had told him, in effect, that the universe is not static, Einstein retracted his cosmological constant. He called it his “biggest blunder,” which big bang cosmologists rarely fail to mention, taking comfort in his agreement.

The equation from Einstein’s general theory of relativity was adapted for big bang cosmogony, because it could be used to represent a universe in which the initial pressure and outward momentum of the expansion is countered by the universal gravitational attraction. The “Einstein-de Sitter model of the universe” is one such theory. It holds that gravitation will bring the expansion of the universe to a halt at the end of eternity. Preference for this view has posed a problem for cosmologists, because all indications are that there is far less matter in the universe than such a limit to its expansion would require.

Spatiomaterialists critique. Ontological philosophy has a different way of interpreting Einsteinian cosmology which is based on its ontological explanation of the truth of Einstein’s general theory of relativity. Spatiomaterialism assumes that space is an infinite, three dimensional substance enduring through time, and it explains why Einstein’s general relativity equation yields true predictions of gravitational phenomena by holding that the accumulation of matter at any location in space causes an inbound acceleration of the inherent motion in the surrounding space. On this view, space is assumed to be infinite, and the so-called called the “curvature of spacetime” turns out to be just an acceleration of the inherent motion of space (that is, an acceleration of the ether, as an aspect of space). If that effect of matter accumulation of space is what makes Einstein’s equation true, then there much to criticize in its use as the theoretical underpinning for big bang cosmology.

The most basic objection to Einsteinian cosmogony is the use of Einstein’s question to represent the entire universe. That is to assume that the universe contains only a finite amount of mass and energy (that is, matter) and that spacetime is finite. But thus far in this ontological argument, we have still found no reason to believe that space is finite in extent or that the total quantity of matter is finite.

This is not to deny that Einstein’s general relativity equation can be used to represent a sizable chunk of the universe. Indeed, the truth of that representation is what was explained ontologically in the General theory of relativity. But when we recognize that it represents only a region of space and the matter contained by that region, we can see that Einstein’s introduction of a cosmological constant was not a mistake at all, but merely a way of representing the infinity of the space and matter outside that region.

Einstein introduced the cosmological constant as a constant of integration in the integration of his general relativity equation. But he introduced it on the right-hand side of that equation. Since that side represents the mass and energy contained in the region, the cosmological constant that was needed to make the universe static seems to represent a repulsive force which is counteracting gravitational attraction.

However, the constant of integration could have been introduced on the left hand side of Einstein’s general relativity equation, which represents the metric of spacetime. That may seem like a mere mathematical correction to the geometry of curved spacetime. But it could be interpreted as representing the infinity of space and matter beyond the region covered by the equation. If the universe is infinite, rest of the universe is, in effect, tugging at the edges of the finite region of spacetime represented by the equation, keeping its overall curvature flat. The cosmological constant does not represent a negative force that increases with distance, but simply a constant of integration that must be included in order to take into account the rest of the infinite universe.

Thus, ontological philosophy would lead us to see Einstein’s greatest blunder, not as introducing the cosmological constant, but as giving it up. For that concession comes from failing to recognize that what is described by his general theory is just a gravitational force that works through space in a world in which space is an infinite substance enduring through time, that is, in which space and time are absolute. Einstein’s mistake was to believe in spacetime.

Thus, we conclude that the truth of Einstein’s general theory of relativity gives us no reason to think that the universe might be expanding and, thus, no reason to believe that it began with a big bang.

Empirical foundation of big bang cosmogony. Though Einstein’s general theory of relativity is the main theoretical reason for believing in a big bang, it is probably not the most important reason. The most persuasive reasons are empirical. It seems to be the best explanation of three phenomena: the apparent explanation of the universe, the proportion of helium in the universe, and the background radiation. However, in a spatiomaterial world, as we shall see, there is another possible explanation of those same phenomena, and it is far more plausible.

Hubble’s law. In 1929, Hubble published the result of his work at the Mount Wilson gathering evidence about the spectra of distant galaxies. He reported that galaxies are moving away from earth, and moving away faster the farther away they already are. That is Hubble’s law.

Hubble found a red-shift in the electromagnetic radiation from distant galaxies, that is, a shift of radiation from known sources toward longer wavelengths, and as far as he could measure (about 10 million light years), the red-shift increased directly with the galaxy’s distance. Such a shift could be explained as a Doppler effect. It is well established that the wavelength of a signal sent from an object moving away is elongated. Assuming that the red-shift he had observed is a Doppler effect, Hubble argued that the galaxies he had observed were moving away from earth, and his data indicated that the farther galaxies were away from earth, the faster they were moving. Hubble’s law states that the recession velocity of a galaxy increases directly with its distance, and the constant of proportionality is Hubble’s constant.

Hubble’s own calculation of his constant is now though to have been off by a factor of two, though to this day, there is still considerable uncertainty about what it is. Current measurements seem to cluster around two different values. (One group finds that galaxies have about 15 kilometers per second of additional velocity for every million years of additional distance from earth, while another group finds them to have about 25 kilometers per second of additional velocity for every million years of additional distance from earth.)

The correlation between the distance to a galaxy and the velocity its recession suggests that the whole universe is expanding, because that is how it would appear not only from earth, but everywhere, if the universe were expanding. Though strictly speaking, the red-shift of distant galaxies would not be a Doppler effect, because their recession velocity does not come from moving through space, but rather from the expansion of space itself, it is assumed to come to the same thing quantitatively. (The wavelength of a photon is supposed to increase with the expansion of the space it is crossing.)

Hubble’s law makes it possible to calculate the age of universe, because if galaxies are all receding from one another as that law describes, there must have been some time in the past at which they were all located together at the same point. Current estimates tend to cluster on either an age of about 20 billion years or 10 billion years, depending on which value of the Hubble constant one accepts. There is considerable room for error. First, it is necessary to separate out the “peculiar motion” of galaxies which is caused by local gravitational effect (and that is a significant factor, since nearby galaxies are the ones mainly used to measure Hubble’s constant). And if the expansion of the universe has been slowing down because of the gravitational attraction between galaxies, as cosmologists assume, then the estimate of the age of the universe should be considerably lower (by as much as one-third).

Nucleosynthesis. The measured expansion of the universe supports the idea that the universe began with a big bang, but that idea was first proposed by George Gamow in 1947. The evidence Gamow offered for such a beginning is the prediction of the proportion of helium and other light elements in the universe, which has been confirmed.

Gamow thought of the initial state of the universe as being nothing but an intense radiation with a very high temperature. He assumed that the objects with rest mass would be created by high energy photons. (Since most of the rest mass in the universe is now composed of baryons, that would not explain what happened to all the antibaryons that must have been created at the same time.) And Gamow assumed that the pressure of radiation at such a high temperature was responsible for the expansion the universe, though without any space outside into which it could expand, it had to create its own space.

Particles would be created, and as the expansion continued, the temperature would fall. Gamow recognized that at some point the density of nucleons and the energy of their interaction would be enough for nucleons fused into small nuclei to be stable (between 10 and 100 billion degrees Kelvin). He explained the proportion of helium (with two protons and two neutrons) that is found in the universe (about 25 to 28 percent by weight). Similar reasons can be given for the proportion of matter in the form of deuterium (one proton and one neutron), helium-3 (two protons and one neutron), and some lithium and boron.

Since there is no other plausible explanation of their relative abundance in the universe, this is good empirical evidence of a period in the past during which the temperature of the universe was once much higher than it is now and that is has been falling since then.

Background radiation. In 1966, Arno Penzias and Robert W. Wilson, discovered radiation coming from all directions in space, day and night, every season of the year in the microwave region of the electromagnetic spectrum. It was the wavelength that one would expect of an object with a temperature of 2.7 degrees above absolute zero. They recognized that the radiation must have a cosmic source, and they argued that it must have been caused by the big bang and the subsequent expansion of the universe.

The radiation must come from a period long after the nucleosynthesis discovered by Gamow, because for a long period of time, the electromagnetic radiation would have been sufficiently energetic to break any bonds that electrons might form with the nuclei bouncing around at the time. About 100,000 years after the big bang itself the universe would have expanded enough for the temperature to fall to a level that would allow atoms to be stable. Neutralizing the charges of electrons and nuclei in that way allowed photons to pass unhindered for great distances. The period at which the universe became transparent would explain the origin of the cosmic background radiation.

These empirical reasons for believing in the big bang are independent of general relativity. Even though spatiomaterialism can reject Einsteinian cosmology because of the assumptions it makes, these observations are still evidence for the big bang. But since they are just observations, they support the belief that the universe has been expanding ever since a big bang only if that is the best explanation of them. Thus, the empirical foundation for contemporary cosmogony can be undermined by offering a better explanation of those observations. There is at least one way that spatiomaterialism can do just that.

Spatiomaterialist cosmogony. The spatiomaterialist alternative to received cosmogony will be presented here in two stages. First, I will show that spatiomaterialism is not falsified by the evidence for the big bang because is has another way of explaining it, a way that make it a better theory, at least in the eyes of ontologists. Then, I will show that there is a variation on it that is an even better explanation of all the relevant evidence, because it also explains certain observations that are currently acknowledged to be puzzling and problematic. I call the first stage of this explanation “the big shrink” and the second stage the theory of “local big shrinks.”

The big shrink. It is possible to explain all the observations offered in support of the big bang theory without supposing that the universe is expanding, because they can be explained at least as well by the shrinking of particles with rest mass in size. Spatiomaterialism assumes that space and matter are infinite in extent and that they have existed from eternity. But let us assume for now that the universe as we know it did begin with a singular event, which is currently called the “big bang.” But instead of assuming that it was like an explosion, let us assume it was more like an implosion. Instead of a big bang, it could have been a big shrink.

This theory assumes that until that point in the history of the universe, space was filled with matter. All the particles with rest mass were so big that they coincided with every part of space. Since according to our theory of the basic particles, the proton never decays, we should think of space as being densely packed with baryons, or triplets of quarks, all existing side-by-side everywhere. There need not even be any electrons, if these baryons were all neutrons. There is nothing inconceivable about infinite space and matter existing in that condition from eternity.

Possibility of big shrink. What is called the “big bang” could have been what happened when all that rest mass matter started shrinking. Assume that the shrinking happened simultaneously everywhere in space. Set aside for now why it occurred when it did. Just suppose that it happened. Our theory about the nature of the basic particles explains how it would be possible.

Such a shrinkage of particles with rest mass is possible, on our theory of the basic objects, because baryons are constituted by both space and matter. If quarks are weakons traveling on twisted circular pathways provided by neutrinos, the condition of matter at the beginning could be explained by the huge size of those neutrinos. The shrinkage of rest mass matter in size could then be explained by the neutrinos shrinking in size. The quarks (and, thus, the baryons) would become smaller, and since there is only a finite amount of matter in any finite region of space, distances between baryons would begin to grow. Thus, the “big shrink,” as I will call it, would not require space to expand.

The strong forces between baryons, mediated by mesons, could have held neutrons together from eternity. But as baryons began to shrink, spaces between them would begin to open up, and at least at the boundaries where empty space appeared, particles and small clumps would break off and start moving and interacting with one another. The strong force is actually a repulsive force at small distance between independent hadrons, tending to keep them apart, but the temperature might be high enough in places for them to fuse again into masses. The weak force would make neutrons decay into protons, leaving electrons to interact independently, and if the temperatures were high enough, they would interact like a plasma. But let me set aside for now the description of how they move and interact in order to focus on the effects of the big shrink on photons and the basic forces of nature.

Photons would be generated in the usual way by the interaction of charged objects. But photons would be unaffected by the shrinkage of rest mass matter, because they are not constituted by neutrinos. They are quantum cycles that coincide with space in a way that moves them along at the velocity of light, though at first they would not be able to travel very far before they were scattered by charged objects.

Nor would the electromagnetic force be affected directly by the shrinking of neutrinos. The electromagnetic field is imposed on space, as we have seen, by electric charges, and they would do so in the same way (which we have assumed involves a universal pulsation in which a 1800 phase shift distinguishes negative from positive). Since space is not changed, this reflection of electric charges in space would be the same. However, the particles carrying the electric charges would be much larger, and thus, the electric and magnetic forces would be much weaker relative to the weak force. That is, virtual photons by which the electromagnetic force acts on particles with rest mass would be the same size, but the charged particles would be much bigger and, thus, less affected by their point like charges.

The short range forces would dominate interactions. The weak force is also mediated by gauge bosons, and the main role of virtual weakons is to exert forces that keep the quantum cycles of weakons traveling along their neutrino pathways and to keep the neutrinos lined up as twisted circles in quarks, though they also mediate all the decay patterns of high energy particles. The color force would work the same way, given our theory of the basic particles, because gluons are just how the weak force keeps the quarks lined up either in triplets or quark-antiquark pairs (when the weakons are contorted by traveling twisted circles). Hence, the strong force would work the same way as it does now, except that the mesons would be much larger and its reach would much greater. Since there is a neutral weakon, Z0, the weak force could also mediate elastic collisions among particles as well as keeping the basic objects together.

The gravitational force would also work basically the same way with swollen rest mass matter, because on our theory, it is just the effect of accumulations of matter on the inherent motion in space. But there would be one important difference. The particles with rest mass would be much bigger and have much less rest mass. The quantity of rest mass depends on the number of quantum cycles per second involved in their constitution, and with larger neutrinos, the weakons would have farther to travel. Baryons and leptons would, therefore, have fewer quantum cycles per second, or less rest mass. That would affect the sizes of the quantum kinetic cycles by which particles with rest mass move across space, because according to this ontological explanation of quantum mechanics, the wavelengths of the quantum kinetic cycles are scaled according to the mass of the object (that is, constitute momentum, not just velocity). The smaller rest masses of particles together with their swollen sizes would mean, however, that the gravitational force has considerably less effect on what happens.

Compatibility of spatiomaterialism. Unlike the big bang, the big shrink is compatible with spatiomaterialism. It is not necessary to deny that space is infinite nor to believe that space is expanding. And given the spatiomaterialist ontological explanation of the basic particles, we can conceive how the big shrink would work. There would be no change in Planck’s constant, only a change in the size of neutrinos. But as the shrinking of neutrinos continued, the quantum cycles constituting particles with rest mass would speed up. The increase in their rest masses would mean an increase in gravitational force-field matter, because the gravitational force is in proportion to mass and the distances in space across which the force is acting will be increasing. That is, the force-field matter of the gravitational field would increase with the total quantity of quantum matter. But that seems to be a violation of the conservation of matter.

Such an increase in the total quantity of matter in the universe is not, however, unthinkable at this point. It does not pose the same problem for spatiomaterialism as the expansion of space would, because it is possible to conceive how it would happen, even in an infinite world.

To be sure, it does violate the conservation of matter. But we merely used the principle of the conservation of mass and energy as working hypothesis by which to figure out what spatiomaterialism had to assume about the forms of matter in order to explain the natural processes described by classical physics. Having done that, we are now in a position to derive new conclusions about the world from spatiomaterialism. If the universe began with a big shrink, then the total quantity of matter has been increasing ever since. That is just the nature of a spatiomaterial world with the big shrink.

However, at the second stage of this theory, we will see how matter can be conserved, even though its total quantity increases throughout the big shrink.

Explanation of relevant phenomena. As the shrinking of rest mass matter continued after the beginning, physical processes would take place that could explain the phenomena cited as evidence for the big bang. At first, the strong (and weak) force would dominate, holding large clumps of neutrons together as they separated from one another. They would be cool, but energetic interaction would occur only at their boundaries. Assuming that the shrinking were fast enough, the continued shrinking of particles with rest mass would eventually break up the clumps of neutron into smaller clumps and independent baryons along with other particles. But since huge groups of baryons would already be separated by huge distances, the increasing strength of the gravitational force would draw the still swollen matter into collisions with one another where the temperature would be high (relative to their size).

Nucleosynthesis. As some point in the shrinking of matter, the temperature would reach a point at which larger clusters of neutrons would be broken up by the kinetic energy of their interaction and only small nuclei would be stable. Since it would depend on the temperature of their interaction, such a process could give rise to the same proportion of helium and other small nuclei that Gamow predicted.

Background radiation. There would also be point during the big shrink when electrons and nuclei through out the universe would become coupled in atoms, making it possible for photons to travel long distances without interacting with charged particles. The wavelengths of those photons would mirror the swollen sizes and lowered masses of the charged particles that were interacting, and since those elongated photons would not shrink further, that would explain the cosmic background radiation. We are parts of galaxies in which rest mass matter is much smaller as a result of the continued shrinking, and thus, the photons generated when nuclei and electrons were much larger would have a much longer wavelength than photons generated by similar processes on earth.

Hubble’s law. The big shrink would explain why Hubble’s law appears to be true. At some point during the big shrink stars would from, and assuming that the shrinking has continued throughout the universe to this day, the radiation generated by those bigger and slower processes would have a longer wave length. In fact, there would be a correlation between the red shift observed in galaxies and their distances from earth, because light from more distant galaxies would have spent more time traveling before being intercepted by us, and it would be measured as longer by us, since the rest mass matter constituting us would have shrunk more since it was emitted than from galaxies that lie nearer to earth. To be sure, the red shift would not indicate the expansion of space nor the velocity of their recession, but rather how much matter had shrunk since the time the light was emitted. That would require a reinterpretation of Hubble’s constant. However, there would still be a correlation between the red shift and distance, which is the observation in which Hubble based his law about recession velocities. And it would be possible to use the red shift to measure the relative distances of faint galaxies.

It is not impossible, therefore, to explain the three main observations used as evidence for big bang cosmology in another way — one that is compatible with spatiomaterialism. And since the big shrink theory does not have to hold that something comes from nothing, it is prima facie a better theory, if it possible — at least in the eyes of naturalists, who believe that the natural world is constituted by substances that exist independently of themselves.

The possibility of big shrink, instead of a big bang, makes it possible, therefore, to believe that the universe is infinite in every way, except for the finite divisibility of matter. Both space and time are infinite in both senses, being infinitely divisible, or continuous, as well as infinite in extent. Time is eternal not only in the direction of the future, but also toward the past, for it is not necessary to believe that substance comes into existence, as entailed by the big bang theory, though there was a time when the big shrink began. And since space is infinite in extent, the total quantity of matter in the universe can also be infinite, even though there is a finite quantity in any finite region of space.

To be sure, the big shrink does imply that the total quantity of quantum matter in any closed region of space is increasing. But that extra matter does not come from nothing. It comes from the matter that exists at the time and the shrinking of neutrinos. Since neutrinos are just an aspect of space having to do with its interaction with weakons, neutrino size could be just a changing property of space.

The increase in the total quantity of quantum matter in any closed region is conceivable because matter is finitely divisible. The existence of elementary units of matter is the only way in which the universe does not have a twofold infinite in its basic aspects: time, space and matter. And there is, as we shall see, a way that the total quantity of matter in sufficiently large regions of space can be conserved even though quantum matter increases during the big shrink.

There is, however, still a problem about big shrink cosmology, because it does not explain why the big shrink happened when it did. Even if the substances constituting the universe always existed, the big bang still implies there was a change at some moment when rest masses suddenly started shrinking. Why did it happen then?

Local big shrinks. Not only can spatiomaterialism offer a better explanation of the observational evidence used to support the big bang theory than the big bang theory, but like so many times before in this ontological argument, it opens up the possibility of a explanation which heretofore has not even been considered. In this case, the fruitfulness of spatiomaterialism as a way of explaining the natural world is shown by its solution to the problem about when this remarkable event occurs. That is the second stage of the spatiomaterialist ontological explanation of the origin of the universe, the “theory of local big shrinks.” What is more, however, it solves other cosmological puzzles posed by current astronomical observations. Thus, unless this approach is on the wrong track, some such theory as they will make a credible claim to being the best explanation of astronomical phenomena, according to the empirical method of science.

It is not necessary to explain why the big shrink occurred when it did in order to believe that substance has always existed, because its is possible to hold that the big shrink is a local event, rather than a global event. A big shrink could occur repeatedly as time passes, but in different places at different times. That is the theory of local big shrinks. It holds that the universe has always existed pretty much as it appears now.

The theory of local big shrinks is, therefore, a “steady state” theory of the universe. Such a theory was advanced in 1948 by Herman Bondi, Thomas Gold, and independently by its most famous defender, Fred Hoyle. Their steady state theory accepted that the universe was expanding, and it held that matter comes into existence as hydrogen atoms (or, later, so called Planck particles). This was the result of a so-called “creation field,” which is one way of interpreting Einstein’s cosmological constant. A creation field requires new physical processes, but so does the big bang theory. Thus, it was once considered a viable alternative to the big bang theory.

The steady state theory has, however, fallen into to disfavor. It could not explain the cosmic background radiation, when it was discovered. And since it assumes that the universe appears the same way at every moment in its history, it cannot explain the evidence that the universe was previously in a radically different condition. For example, quasars are extremely intense sources of radiation, but since they tend to have an extremely high red shift, they must be far away (according to Hubble’s law), and thus, most cosmologists take quasars to be characteristic of a much earlier era in the history of the universe.

The local big shrink theory is, however, different from the traditional steady state theory. It does not agree that the universe is expanding, but explains that appearance by the shrinking of rest mass matter. And as we shall see, it can explain the background radiation. Indeed, it can explain all the phenomena covered by the big bang theory, including quasars.

The scale of the local big shrink on this theory is roughly that of a supercluster of galaxies. It has recently been recognized that the large scale structure of the universe includes not only stars configured as galaxies, but also clusters of galaxies, and clusters of clusters, or superclusters of galaxies. Indeed, it now seems that there are vast empty regions of space between such clusters of galaxies that look something like soap bubbles because of how they are bounded by galaxies. Let us assume, therefore, that from time to time in such empty regions, very swollen matter comes to exist and starts to shrink as described above. Let me also emphasize some aspects of this process and also refine the assumptions we are making about the big shrink.

We assume that particles with rest mass start off packed together in a swollen condition coinciding with a huge region of space. Assuming it was made of baryons held together by the strong force, it would be like a giant neutron star. Since this matter would be surrounded by empty space, there would be a gravitational attraction that tends to pull all the particles towards the center of mass. It might seem, therefore, that a local big shrink could not develop as described above, because the gravitational force would accumulate enough to cause a giant black hole. But that is not inevitable, for two reasons.

First, the condition of matter at the beginning makes the gravitational force weaker in its effect. The weakons are traveling the pathways of much larger neutrinos in baryons and charged leptons, and thus, those particles are constituted by fewer quantum cycles per second than the same kinds of particles on earth. On our theory, that means that they are not only larger, but that they also have less rest mass. Hence, the gravitational field that they impose on space will be much weaker than it comes to be later on.

Second, let us assume that the shrinking is initially much more rapid than it is later. In fact, we will assume that the shrinking slows down asymptotically to a limit that is not much smaller than matter constituting earth. Though at first, the electromagnetic force is weaker and interactions among basic particles are dominated by the strong force (and the weak force), the rate of shrinkage could be fast enough for spaces to open up between huge clumps of baryons that are still held together by the strong force. These huge clumps of matter would still attract one another by gravitation on the largest scale, but if the shrinking were fast enough, they would remain isolated from one another, and the main role of gravitation on a smaller scale would be to help the strong force hold the remaining clumps of matters together.

The same process of division could occur more than once. As particles with rest mass shrank further, baryons would still tend to stick together because of the strong force, and thus, the clumps would subdivide into smaller clumps, opening up huge distances between them as they continued to shrink. And those sub-clumps of matter might do so again. Such a process could explain the large scale structure of a supercluster of galaxies, that is, the huge distances between clusters of galaxies, between local groups of them, and ultimately between single galaxies.

The rapidity of the initial shrinking means that this phase of the local big shrink would be completed in much shorter period of time than assumed by the big bang theory, because the local big shrink occurs in a much smaller region and it does not require galaxies to spend a lot of time moving away from one another. Instead, the galaxies would “precipitate out” from the original mass of swollen particles as they shrink in size.

Eventually, however, the shrinking of the basic particles would weaken the strong force relative to the electromagnetic force, and the strong force, together with gravity, would no longer be able to hold matter together in huge clumps. In addition to the kinetic energy of the collision among masses of baryons, the repulsive electromagnetic forces between protons would help separate them, and the short range repulsive force between baryons that are not bound together by the strong force would keep them separate. Thus, baryons would break up into smaller and smaller clusters and eventually into individual baryons.

As the shrinking continued, the temperature would fall, because the distances separating baryons and bunches of baryons would increase. Gravitation would be pulling them into regions of dense collisions, but they would still be too swollen and light to form stars. This is the point at which the “nucleosynthesis” that explains the proportion of helium and other simple nuclei in the universe would take place. Large groups of baryons would be unstable at that temperature, but simple nuclei would be stable and remain stable as the temperature fell.

Not long after that, electrons would couple with nuclei to form atoms, and since photons would be able to travel much longer distances, more photons would escape into the space beyond these more or less isolated clusters of matter, and there would be a vast increase in the radiation from them. That would account for the cosmic background radiation, because matter would still be swollen enough for the photons released to have longer wavelengths. The size of the particles would make it appear that it is a 2.70 Kelvin blackbody radiation, though actually it would be a much higher temperature relative to swollen rest mass particles. To be sure, photons with even longer wavelengths would have been emitted by clusters of matter prior to that, when matter was even more swollen. But that radiation would not be nearly as intense, because photons could come only from the edges, as the radiation from stars. When the region became transparent, however, photons could also escape from throughout the clusters of matter, and that is what is observable.

By this point, the “precipitation” from the shrinkage of matter would already have isolated galaxies from one another and, presumably, made the distribution of matter in each galaxy somewhat uneven. But since particles with rest mass have been shrinking in size and increasing in rest mass, the total mass accumulated in these local regions would increase and gravitation would begin to play the dominant role in what happens.

To be sure, from the beginning, gravitation would have been attracting clusters of matter toward one another, and that attraction would also increase as rest mass increased. But since, initially, gravitation was not strong enough to keep up with the effects of shrinking, clumps of matter would separate off from one another leaving vast distances between them that gravitation could not overcome quickly enough. Thus, gravitation would wind up exerting much the kind of attraction among galaxies that is observed now.

Within each galaxy that precipitated out during that earlier process, however, the continued shrinking of matter would increase the effective gravitational force, because fermions would be smaller and have greater rest masses than ever. Gravitation would play two roles at this stage, pulling matter throughout the galaxy towards its center and turning regions of relatively denser accumulation of matter within each galaxy into stars.

The gravitational attraction at the scale of an entire, separate galaxy would create enormous pressures at the center, where matter would accumulate, and with smaller, heavier particles, it would be enough in most galaxies to create giant black holes which would gobble up all the extra matter that had accumulated at the center. They would give off, at least for a while, enormous quantities of energy as matter tried to spiral into them, and their magnetic fields might even spew out prodigious quantities of particles in certain directions at enormously high velocities. And the gravitational field centered on such a black hole would organize the motion of matter throughout the galaxy.

On a more local scale, gravitation would cause the formation of stars of various sizes. Regions of highest density would tend to be the first to form stars, and those giant stars would explode rather quickly as supernovae, spewing heavy nuclei throughout the regions around them. Smaller would form from smaller variations in density, and since most of them would form later, the planets that formed out the matter spiraling into them would be rich in atoms with heavy nuclei.

[Perhaps, some aspect of the process of galactic development by “precipitation” from the local big shrink would even account for the observations that now lead to the belief that there must be a great deal of dark matter that exists in an unusual form.]

The formation of a black hole and stars would give galaxies the appearance they now have, for matter would be much smaller and heavier, radiating photons with much shorter wavelengths. Visible light would make galaxies observable from great distances, and their spectra could be examined by astronomers. Assuming that the shrinking of matter had not quite reached its asymptotic limit when it was emitted, a red shift is precisely what we would expect to observe from earth, where the shrinking has gone on longer. On the other hand, assuming that earth is very close to the asymptotic limit where matter stops shrinking, it would also explain why there are no galaxies with a blue shift, as one would expect, if the shrinking went on.

The theory of local big shrinks would imply, nevertheless, that Hubble’s law is false. Since local big shrinks would be occurring at different times at different locations throughout the universe, there would be no general correlation between the red shift of a galaxy and its distance from earth, as Hubble concluded from his observations. But that does not necessarily falsify the theory of many local big shrinks.

The reason it escapes falsification is the difficulty in measuring the distances to faint galaxies. Hubble was able to measure galaxies only up to about ten million light years away, and even current attempts to extend the range of independent measurement of distance beyond that do not yield reliable, independent readings of distances to galaxies beyond our supercluster of galaxies. The most reliable measurement of distance depends Cepheid variable stars, whose intrinsic brightness is known, but it does not reach beyond our own Virgo cluster of galaxies, that is, about 50 to 75 million light years away. And though supernovae and sheer brightness of galaxies can be used beyond that limit, the reliability of those standards has not been established.

The correlation between red shift and distance within our supercluster of galaxies is what would be expected, according to the theory of local big shrinks, since it assumes that all those galaxies were generated at roughly the same time by the same local big shrink. The red shift of a distant galaxy within our supercluster would be explained by the length of time that light has been traveling since it was emitted, since both our galaxy would have been shrinking further during that entire period. Thus, the red-shift of a galaxy would be a good indicator of the relative distances to galaxies within our supercluster.

Disagreements about Hubble’s constant tend to cluster around two different values, one yielding about 20 billion years as the age of the universe and the other yielding about 10 billion years. That disagreement may be due, in part, to the attempt of one group of astronomers to measure the Hubble constant by more distant galaxies, some of which are beyond our supercluster, where it is much more difficult to measure distance.

Thus, it is possible to reject Hubble’s law as a misinterpretation of data from relative nearby galaxies in terms of the big bang theory and its assumed expansion of the universe. But recognizing its falsity would revolutionize out view of the universe, because red-shift would no longer be a reliable way of estimating the distance to faint galaxies.

Not only can the theory of local big shrinks explain all the phenomena on which big bang cosmogony is based, but there are observations that can be explained only by the theory of local big shrinks. For example, there is accumulating evidence of stars whose lifetimes are longer than the lower estimates of the age of the universe based on Hubble’s constant. But the most spectacular fallout is that it explains the observation of quasars.

Quasars are extremely red-shifted light sources that seem far too intense to be located as far away as they seem to be according to Hubble’s law. Its radiation is typically much more intense than the rest of the galaxy of which is a part. The radiation seems to come from something like a star, because its strength can vary too quickly for an entire galaxy to be its source. And it is widely assumed that the only currently plausible such an enormous quantity of energy is a giant black hole which is drawing large quantities of matter beyond the event horizon (at the Schwartzschild radius). But since they have much greater red shifts than is measured in galaxies from our supercluster, they are assumed to have existed very early after the big bang. Relatively few have less than an enormous red shift of z = 2, that is, with wavelengths twice as long as those generate by similar processes on earth, and some, with red-shifts approaching z = 5, seem to come from sources that existed as long as 12 billion hears ago. Twelve billion light years is an enormous distance in space, and it is quite astonishing that we are receiving light from a source that far away, because it means that the universe must be completely transparent throughout a sphere with that radius.

However, all these observations are precisely what would be expected on the local big shrink theory. As we have seen, it is likely that black holes would form early in the history of isolated galaxies because of the accumulating gravitational forces at the centers of those clusters of matter. Their formation early in the history of galactic development would explain their relatively greater red-shifts, because at that point in their development, particles would still be quite swollen. Assuming that the sizes of the particles varies with the wavelengths of the photons that their interactions give off, it would mean that matter at that stage is from two to five times the size it is on earth. The intensity of the radiation could be completely explained by its origin in a black hole, because quasars could be located so much closer to earth that would be required by Hubble’s law (though those with high red-shift must be located beyond our supercluster of galaxies). And this theory does not require us to believe that the universe is so transparent that photons can travel without being intercepted for 12 billion light years in every direction from earth.

Thus, quasars cannot be used as evidence against the theory of local big shrinks. It is much more likely that they are not how the universe looked early on after the big bang, but simply how it would look anywhere in the universe where the local big shrink had reached the stage at which galaxies were separate and black holes began to form at their centers.

But there is still one ontological objection to the theory of local big shrinks. Even if the universe as a whole is eternal and infinite, this theory seems to imply that matter is coming into existence, which contradicts the assumption of the conservation of matter (though not the more basic ontological principle that something cannot come from nothing). Where would the matter for the big shrink come from?

Again, however, spatiomaterialism seems to have an answer — an answer that also has to do with black holes. The one puzzling feature about black holes is what happens to the matter that falls into them. If there is a singularity at the center of the black hole, as seems required by the infinite force there, the matter seems to just disappear forever from the universe. The size of the Schwartzschild radius is the only indication of how much matter has disappeared into it.

However, that loss would not be permanent, if black holes were the source of the matter that shows up in local big shrinks. The laws of physics do not cover conditions as extreme as those that hold for the singularity in the center of the black hole, and thus, it is possible that matter is transformed into an aspect of space, that is, into a condition of space that could be the source of the matter that shows up as local big shrinks. This condition would hold only when enough matter had been gobbled up by black holes in the galaxies surrounding some vast empty region. But it is possible that when space has absorbed enough matter through those black holes, it gives birth to a big shrink in the nearest vast region of empty space between superclusters of galaxies.

There may be no need, therefore, to believe that the matter that comes to exist at the beginning of the local big shrink or the matter that comes to exist as particles with rest mass shrink and become more massive is coming into existence our of nothing. Instead of the “creation field” of earlier steady-state theories, what is needed is only a transformation field, in which matter absorbed by space from black holes re-emerges as a local big shrinks.

That is a process that could go on forever. Matter would be recycled, and the universe need never run out of room, for gravitational attraction would always be shrinking existing superclusters of galaxies away from some huge region of empty space or another. But it could mean that all galaxies are ultimately destined to be consumed by black holes.

No doubt, this theory of local big shrinks needs further refinement before it will be fully reconciled with what is known about physical processes. But it illustrates what could be true, if this is a spatiomaterial world and physics is explained ontologically.

Conclusion about local regularities.What has been established by Cosmology, and more broadly, by this ontological explanation of contemporary physics?

It is clearly not a necessary truth of ontological philosophy. This spatiomaterialist ontological explanation of the basic particles of physics and the origin of the universe is, like its explanation of quantum mechanics, more speculative than that. It is obviously incomplete, for there are many quantitative details to be filled in. And it would be surprising if it is not mistaken in some ways, especially the theory of the big shrink. What I have said above will have to be changed, not merely expanded.

Even what has been said about Einstein’s special and general theories of relativity is not a necessary truth. It is also just an ontological explanation of the truth of relativity theory. But I do claim that it is closer to the truth that contemporary physics. That is what needed to be shown to pay off the mortgage on spatiomaterialism and use it as the foundation for ontological philosophy. But I do not mean to make such a strong claim for what has been said about quantum mechanics, the basic objects, and cosmogony. They are more speculative, and I suspect that there still much gold to be mined in the hills of the theory of local big shrinks.

What I believe has been show in these past two chapters, on Quantum mechanics and Cosmology, is that some such theory is probably true. It is possible to give an ontological explanation of the truth of quantum mechanics, high energy physics, and big bang cosmology based on spatiomaterialism. That shows, at least, that spatiomaterialism cannot be rejected by claiming that it contradicts what has been discovered empirically in any of the fields of physics. But it also shows the fruitfulness of spatiomaterialism in physics.

The widely acknowledged problems about the theories in these fields of physics make them a rather flimsy foundation for denying a theory of empirical ontology. Though the big bang theory, for example, is warmly embraced by popular culture, where mystery and faith live comfortably with relativism, it is held with much less confidence by physicists, if only because they are, as naturalists, more inclined to believe that that the natural world is constituted by substances that exist independently of themselves. Though it is not an explicit principle of science, it simply does not make much sense to hold that something can come from nothing. Puzzles in the other fields likewise make scientists more skeptical than dogmatic. Few scientists would claim that physics has already discovered the deepest truth about the nature of what exists.

By saying that spatiomaterialism is fruitful in physics, I mean that it opens up new ways of explaining the observations made by physics. But to show that there is no reason to doubt that some ontological explanation along the lines of those given here is also to show that some such theory is probably true, because any such theory would explain more of the phenomena and explains it better than physics does at present.

What explain the power of spatiomaterialism to cast new light on physics is the difference between ontological-cause explanations and efficient-cause explanations with which we began in the Foundation of ontological philosophy. Instead of trying only to discover the laws by which it is possible to predict and control what happens, empirical ontology tries to discover the substances that would explain why those laws are true. In addition to efficient causes, it seeks ontological causes.

In these chapters on contemporary physics, we have seen what ontology can add, when it infers independently of empirical science to spatiomaterialism as the best ontological explanation of the natural world. Whereas physics relies on mathematics to represent the quantitatively precise relationship among properties by which it can predict the outcomes of measurements, ontological philosophy relies on our spatial and temporal imagination to represent geometrically the substances whose aspects are those properties.

The kind of mathematical representations used by physics are based on Cartesian coordinates, and that means that everything can be reduced to algebra, that is, basically, arithmetic. As we saw in Relations, the explanations of the truth of arithmetic and geometry are independent on one another. One comes down to counting units, while the other comes down to representing spatial relations spatially (or, more accurately, as we shall see, spatio-temporally), and both can be shown to correspond to aspects of a spatiomaterial world.

The power of ontological philosophy to illuminate contemporary physics comes from how spatiomaterialism adds spatial and temporal imagination to the more abstract mathematical imagination that is the workhorse of physics. Keep in mind that ontological-cause explanations do not replace efficient-cause explanations, but rather explain their truth. That provides a deeper explanation of the world, because it adds constraints that are understood through spatial and temporal imagination to constraints that are understood through mathematical manipulations. The puzzles in physics arise from the limitations inherent in its mathematical representations, mainly its attempt describe physics with nothing but the algebraic representations introduced by Descartes, and spatiomaterialism sheds light on physics, because it shows how it is possible to use spatial and temporal imagination to impose additional constraints on our beliefs about the world. And that is what I believe has been shown in these past four chapters. It points the way to new physics, a physics that is ontological. Some such ontological explanation of physics is possible.

In order to refute this argument, in other words, what is required is a proof that no such theory is possible. It is not enough to point to details that have not been explained. Nor even to point out ways that it is mistaken. I would be surprised if there were no mistakes in these theories. But goal in formulating them has not been to avoid small errors, but to show a larger truth. I believe I have done that. And to show that I have not, it is necessary to show that no spatiomaterialist ontological explanation of the truth of physics can be given. Having answered the challenge that contemporary physics might be thought to pose for the belief that this is a spatiomaterial world (and solved, in the process many of its unsolved problems), that is the challenge I make to physicists.

This concludes the ontological explanation of local regularities, but that is not all that is regular about change in a spatiomaterial world. We have been focusing, as physics usually does, on regularities about the motion and interaction of bits of matter that can be described relative to those bits of matter. We have seen the role that space plays in their explanation. But since the bits of matter all coincide with parts of space, space plays another role in making change regular, namely, how the wholeness of space makes the change that occurs in whole regions of space regular. That is what will be taken up at this point, and the conclusions to be drawn from that part of the argument are necessary truths of ontological philosophy. What will be said global regularizes does not depend on the truth of this ontological explanation of the truth of physics, because except for the implications of quantum mechanics for chemistry, it does not depend on contemporary physics at all. However, just as in the explanation of contemporary physics, the power of spatiomaterialism to cast light on what has been discovered empirically by these less general branches of science comes from how it adds a constraint to its conclusions that is understood through spatial and temporal imagination. And what is more, those conclusion will include an explanation of the nature of the faculty of imagination that makes it possible.

Global regularities about change. Global regularities are regularities about change in a spatiomaterial world that hold of whole regions of space.

Change, as an aspect of the substances constituting the world, involves something more than just properties and relations. It also depends on the temporal aspect of (the existential aspect of) the nature of substance as substance. Having explained (in the first two chapters of the Necessary Truths of ontological philosophy about What is) how properties and relations are aspects of a world constituted by space and matter (given how they exist together), we have already found in Change how the endurance of space and matter through time as substances explains local regularities about change. In the remainder of this ontological explanation of change, we shall see how the same ontological causes also explain global regularities about change. There are four kinds of global regularities, explaining, respectively, the truth of the first law of thermodynamics, the second law of thermodynamics, the principles of mechanics, and two unrecognized laws about evolutionary change.

There is, besides local regularities, another kind of effect that space has as an ontological cause. The two principles about local regularities describe limits that the structure of space imposes on how bits of matter change locations relative to one another and act on one another because they coincide with parts of space. The reason that there are also necessary principles about global regularities is that the parts of space all fit together as a whole. Bits of matter must move and interact (if they can move and interact act all) in some part of the same space that contains all the bits of matter in the world, and that means that the changes they undergo are all interconnected in a regular way.

The changes that occur in one place must affect bits of matter that are located nearby before they affect what happens farther away. That is a consequence of the principles of local motion and local action. But such effects do spread out in space as time passes, affecting more and more of the world. And it is a reciprocal relationship, because what happens elsewhere in space also has effects that spread back in space towards it. The structure of space with which they coincide helps determine how each event affects what happens elsewhere. But since that structure entails a wholeness about space, the motion and interaction of the bits of matter in any region of space must all add up in space as time passes. And insofar as the bits of matter are located in a region of space that is closed or isolated from the rest of the world, the way that all their local changes add up over time in the whole region may be regular. Since such regularities would hold of whole regions of space, I will call them “global regularities.”

Space is an ontological cause of regularities about change, because space and matter together constitute the world, and change is just an aspect that those substances have because they endure through time. We have seen how space is an ontological cause of local regularities. It causes global regularities in the same way. But global regularities are different, because they depend on a further aspect of the nature of space, the wholeness that is entailed by the geometrical structure of space.

Local regularities about change in bits of matter are caused ontologically by space, because the bits of matter all coincide with parts of space and change is just an aspect of substances enduring though time. It follows from this explanation of change, as we have seen, that two principles hold necessarily about how bits of matter change, namely, the principles of local motion and local action. They hold in every possible spatiomaterial world. But space also helps cause ontologically contingent laws about how bits of matter change, as we have seen by showing that space and matter can explain ontologically the truth of the basic laws of physics (classical and contemporary).

Global regularities about change are caused ontologically by space (and matter) in the same way, by constituting the world in which the regularities are aspects of substances enduring through time. They must be caused the same way, because space and matter constitute everything in the world and everything about the world. But global regularities are a different aspect of the change that takes place, because they depend specifically on the wholeness of space.

Local regularities are aspects of change that are picked out by referring to particular bits of matter and describing how they move relative to one another and how they interact with one another. But global regularities are aspects of change that are picked out by referring to space itself and describing how all the bits of matter in some region of space move and interact relative to it. Because of the wholeness of space, the local changes must all “add up” in the region of space as time passes, and what they add up to are global regularities about change over time.

It may not seem possible to describe motion and interaction relative to space itself, because velocity relative to space (absolute velocity) is not measurable. But that aspect of the relationship of bits of matter to space is not relevant in causing global regularities. What is relevant is that space connects what happens to all the bits of matter so that what happens to each must affect all the others. This comes from a property of space, namely, its wholeness, and it is not affected by absolute motion.

Physics does not necessarily ignore regularities as a result of failing to recognize that space is a substance. It can studies global regularities in practice by taking some more stable material object (such as the box containing a gas of molecules) as its frame of reference (and arguing from what happens in such closed regions to what would happen everywhere or anywhere in the world).

Wholeness is an aspect of the structure of space, because it is a consequence of the essential natures of the parts of space, that is, how they are related to one another geometrically in three dimensions. The wholeness is the fact that all the parts of space fit together in a uniquely simple way.

The aspect of the nature of space that is relevant in causing local regularities, both necessary and contingent, is the geometrical structure itself, that is, the relations among parts that are described by the various theorems of geometry (and trigonometry). That aspect of the space that contains the bits of matter determines, for example, where the inertial motion of a material object takes it, how fast, and which other bits of matter it will interact with as a result. It might be called the “local aspect of space.”

The global aspect of space is its wholeness, or the fact that all the parts of space fit together in the uniform, simple way they do. It means that parts of space in different regions fit together as parts of their more limited wholes in the same way. And the property of wholeness is a cause of global regularities, because it implies that the changes that occur to the bits of matter that coincide with different parts of space must all add up as time passes. How they add up in space also depends on the local regularities and basic laws of physics (which are explained ontologically by the nature of matter and the local aspect of space). But that they all add up as time passes depends on its wholeness. And we shall see how local changes add up in space over time to global regularities.

Space is, therefore, together with matter, the ontological cause of another kind of regularity about change, besides local regularities. That means that there is an ontological necessity about global regularities, because ontological philosophy takes every proposition that follows from its ontological foundation to be a necessary truth. But unlike the two principles about local regularities, the following global regularities (except for the simplest) have only a conditional ontological necessity, because they also depend on matter and space having the specific natures they have in our spatiomaterial world, that is, on the basic laws discovered by physics. Hence, global regularities are only conditionally necessary truths. Their truth is ontologically necessary only in a spatiomaterial world like our own.

In a spatiomaterial world with different physical laws, there might not be any interesting global regularities, because bits of matter do not move and interact at all or they move and interact in different ways. However, as we shall see, the physical laws in the actual world seem to be of just the right kinds to make the most of the wholeness of space in generating global regularities. Many regularities that are not even currently recognized to hold turn of our world out to be ontologically necessary in spatiomaterial worlds like our own.

To be sure, in order to use spatiomaterialism as an ontological foundation for proving necessary truths about the world we had to take out several mortgages. But they are being paid off, and in any case, global regularities do not involve any of the extreme phenomena on which Einsteinian relativity is based.

Two of these mortgages have been paid off. We kept our promise to explain the nature of consciousness in Properties. And the debt that arose from the apparent incompatibility of spatiomaterialism with Einsteinian relativity was paid off by explaining ontologically why Einstein’s theories are true. Indeed, we have seen that all of the basic laws of classical and contemporary physics can be explained as regularities that hold of substances that endure through time as a spatiomaterial world. (See Contingent laws).

Having just completed those explanations, it is relevant to mention, furthermore, that far from casting doubt on spatiomaterialism, contemporary physics provides additional empirical evidence that spatiomaterialism is true. The recognition of space as a substance would solve several mysteries that currently puzzle physics, such as the nature of spacetime, curved spacetime, the relationship between gravitation and quantum mechanics, and even the Bell Inequality entailed by quantum mechanics. And science has further reason to accept this ontological explanation of physics, because it offers a new approach to cosmology which may help solve the prevailing mysteries about the origin of the large scale structure of the universe.

In fact, given our interpretation of contemporary physics, the existence of space as a substance can even be shown by an inference to the best efficient-cause explanation, because substantival space is the efficient cause of the Lorentz distortions (which explain the phenomena of special relativity) and its interaction with centers of mass is the efficient cause of the acceleration of the ether (which explains gravitation). That is, scientific realists about contemporary physics would have to admit that space is a substance, if they believed that nothing exists but the present moment, for the existence of space would be known by its effects on the behavior of matter.

Global regularities are not very sensitive to the extreme phenomena that divide contemporary from classical physics. They are basically unaffected by Einsteinian relativity, as long was we can take gravitation for granted and can assume that the universe has a large scale structure that includes planetary systems like ours. Most global regularities do depend on matter being of the kind found in our spatiomaterial world and, thus, on quantum mechanics. But none of the puzzling phenomena of quantum mechanics are particularly relevant. Global regularities depend mainly on the wholeness of space, that is, how, by containing all the bits of matter, space gives the world itself (as well is regions within it) a determinate wholeness.

There are four kinds of global regularities. Each is recognized in a way by empirical science, as a principle, law or “mechanism” of some kind. But since empirical science does not recognize the validity of ontological explanations, it does not recognize space as an ontological cause of them, and thus, it does not have an explanation of why these regularities hold. Nor does it always fully recognize what the regularities involve. Furthermore, although global regularities depend on the basic laws of physics, they do not follow from those laws alone, and thus, empirical science does not recognize that they are necessary, even when the basic laws of physics are assumed.

The crucial role in explaining each of the kinds of global regularities ontologically is played by space, and more specifically, by the wholeness of space (or, if you will, the “global aspect” of space). Though the wholeness of space makes the world itself whole, it also makes every region of space whole. Thus, global regularities can be seen in regions of space that are somehow closed or isolated from the effects of what happens outside. Since the global regularities are ontological effects of the wholeness of space (and what coincides with it), they arise from inside the region.

The reason there are four different kinds of global regularities is that different aspects of what exists according to spatiomaterialism can be combined with the wholeness of space to generate regularities about the change that occurs in whole regions of space as time passes.

Spatial global regularities.The first kind of global regularity has a single instance, namely, the conservation of matter. It will be called the “spatial global regularity,” because it makes no assumptions at all about the nature of matter except that it is many different substances that each coincide with some part of space or other. Thus, the spatial global regularity can be said to be generated by “spatial causation,” for it is how the wholeness of space makes any kind of matter add up over time. When we take into account the various forms of matter that we distinguished in order to explain the truth of the basic laws of physics ontologically, spatial causation will also explain ontologically the truth of the first law of thermodynamics, the principle of the conservation of energy.

Material global regularities.The second kind of global regularities will be called “material global regularities,” because in addition to the wholeness of space, these regularities depend on matter obeying the basic laws of physics. Alternatively, material global regularities will be said to be generated ontologically by “material causation,” for they are simply how the wholeness of space requires motion and interaction to add up over time when the bits of matter obey the basic laws of physics. That will explain ontologically why the second law of thermodynamics is true.

Structural global regularities. The third kind of global regularities will be called “structural global regularities,” because in addition to the wholeness of space and material causation, these regularities depend on the unchanging geometrical structures of the material objects contained in the region of space, or what will be called “material structures” or “structural causes.” Structural global regularities will be said to be generated ontologically by “structural causation,” because these regularities are how the wholeness of space requires motion and interaction to add up over time when the bits of matter include material structures (or particular structural causes). This explains ontologically the truth of the principles of mechanics (such as the principle of the lever), and when combined with the other ontological effects of material causation, it will explain the sense in which machines can “do work” and certain dispositional properties.

Reproductive global regularities. The fourth kind of global regularities will be called “reproductive global regularities,” because in addition to the wholeness of space, material causation, and structural causation, these regularities depend on how complex material structures go through reproductive cycles, that is, how they go through cycles of structural global regularities that include the reproduction of the structural cause itself as well as non-reproductive work. Thus, reproductive global regularities will be said to be generated ontologically by “reproductive causation,” because these regularities are simply how the wholeness of space requires motion and interaction to add up over time when the bits of matter include complex material structures going through cycles of reproduction. This will explain ontologically the truth of Darwin’s mechanism of evolution, or what might be called the principles of evolution, which includes much more than is currently recognized.

The order of these kinds of global regularities is necessary, because each adds a new ontological cause that works together with ontological causes of all the previous global regularities. That is, we start by assuming that the world is constituted by space and matter (with all the bits of matter coinciding with some part of space or other), and we consider how the wholeness of space constrains what happens to the bits of matter. When no further assumptions are made about the nature of matter, these assumption entail the simplest global regularity (spatial causation). The second global regularity adds that matter with the specific nature described by the basic laws of physics, including the forms of matter that were distinguished. The third adds material structures to the region. And the fourth adds the temporal structure of complex material structures going through reproductive cycles.

The first global regularity is entailed by the basic assumptions of spatiomaterialism themselves, and each of the other three is the result of adding an ontological cause, that is, assuming something further about the nature of what coincides with space in the region: about the specific nature of matter, about its spatial structure, and about its temporal structure.

Thus, considering the ontological causes added to the basic assumptions of spatiomaterialism, material global regularities may be said to be due to “material causation,” structural global regularities may be said to be due to “structuro-material causation,” and reproductive global regularities may be said to be a result of “temporo-structuro-material causation.” Those names bring out the necessary order of the global regularities in a spatiomaterial world.

In the following four sections, these kinds of global regularities will be shown to follow from spatiomaterialism and the kind of matter that explains the truth of classical and contemporary physics ontologically. If nature had a different essential nature, some of the global regularities might not hold. (For example, there would be no structural causes unless matter could make up material objects with geometrical structures that do not change as they move and interact.) But given that matter takes the various forms we used to explain the basic laws of physics, the global regularities are simply how the wholeness of space makes the change in what coincides with space add up as time passes. The ontological effect of spatial causation includes the first law of thermodynamics, or the principle of the conservation of energy. When material causation is added to spatial causation, the ontological effect is the second law of thermodynamics, or the law of entropy. When structural causation is combined with spatial and material causation, we have an explanation of how machines do work. Finally, when reproductive causation is added to spatial, material and structural causation, the ontological effect is evolutionary change.

The ontological explanation of evolution as a global regularity has, as we shall see, implications about what is to be found in nature that goes far beyond what is recognized by evolutionary biology and contemporary Darwinists. But it depends on all the other global regularities, and so we will begin with the simplest and work our way up.

Spatial global regularities.The basic spatial global regularity is that matter is conserved. The total quantity of matter in any closed or isolated region of space does not change. But under certain circumstances, it entails a less general spatial global regularity, the conservation of energy.

“Spatial global regularity” is an appropriate name, because nothing is assumed about the nature of matter except what is entailed by spatiomaterialism (besides space, the existence of many particular substances, each coinciding with some part of space or other.) This global regularity is the purest ontological effect of the wholeness of space.

The regularities caused ontologically by space are not just global. The structure of space also helps cause necessary principles and contingent laws about local regularities (or the basic laws of physics, classical and contemporary). Since bits of matter have spatial relations to one another because they coincide with parts of space, the way those spatial relations change as a result of motion is partly determined by the structure of space. This might be called the local aspect of space.

The global aspect of space, on the other hand, is its wholeness, or the fact that all the parts of space fit together as a single system of locations that are all related to one another geometrically. The wholeness of space is an ontological cause of regularities about change in entire regions of space, because it requires that all the local changes that occur in any region fit together in space as time passes.

When combined with the assumption that matter has a nature that makes the basic laws of physics true, the spatial global regularity (that matter is conserved in a closed or isolated system) entails that energy is conserved in any closed system. That is an ontological explanation of the first law of thermodynamics in a spatiomaterial world like ours.

Conservation principles are called “principles”, because they are supposed to be too basic to be explained by anything else. But conservation principles can be explained ontologically, though in the case of the conservation of matter, the global regularity is so obvious that it may seem to be trivial.

The conservation of matter. Spatiomaterialism holds that matter and space are substances enduring through time. Since matter is a substance, it neither comes into existence nor goes out of existence over time. That is how matter itself is an ontological cause of the conservation of matter. The total quantity of matter cannot change, because matter is a substance. But space is also a ontological cause of this regularity, because matter is contained by space and it is by coinciding with parts of space that bits of matter have spatial relations to one another. Space is what gives particular substances the relationship that makes it possible for them to add up, that is, to be added together and have a total, as we saw in Relations, where the truth of mathematics was explained ontologically.

The relevance of space as a cause of conservation principles is implicit in the way they are formulated. They hold that some quantity does not change in closed or isolated regions of space. But this reference to a region of space indicates a further ontological effect of space. The reason the total quantity of matter does not change in any closed or isolated region of space is that that is how change of any kind adds up in space as time passes when the bits of matter conform to the principle of local motion.

The principle of local motion holds that the only way that bits of matter can change location is by motion, and since it was derived from spatiomaterialism, it is an ontologically necessary principle. But if it holds of all possible change, then the total quantity of matter in a closed region of space cannot change, because to be closed or isolated means that there is a two-dimensional surface surrounding the matter across which no matter is moving That is how bits of matter must “add up” over time because they coincide with space as a substance enduring through time. “Adding up” is an ontological consequence of the wholeness of the space that contains them.

Change in bits of matter adds up in space in the same way that the bits of matter themselves add up in space, except that change takes their endurance through time into consideration. The bits of matter endure though time, but since whatever happens, they cannot change location except by motion, the total matter cannot change in any closed or isolated region of space.

Though it may be obvious and simple, the lack of change in the total quantity of matter in a closed region of space is a regularity about change over time. It is a global regularity, because it has to do with the properties of whole regions of space. The regularity is not just what is assumed by postulating matter as a substance, but rather is explained ontologically by spatiomaterialism, because it is an aspect of the world enduring through time that depends on both space and matter and how they exist together as a world. Thus, the conservation of matter is an ontologically necessary regularity. If the total matter in a closed or isolated region did change, spatiomaterialism would be false. Matter is conserved, therefore, in every possible spatiomaterial world.

The conservation of energy. The first law of thermodynamics is the principle of the conservation of energy. It is a consequence of this spatial global regularity, if we take into account the forms of matter we have assumed in order to explain the basic laws of classical physics ontologically.

This implication will hardly be a surprise, since we used the principle of the conservation of mass and energy as a guide to ensure the completeness of our inventory of the forms of matter that had to be postulated in order to explain the basic laws of classical physics. But since that was just a working hypothesis for distinguishing the various forms of matter, it is relevant, now that we have shown that the forms of matter we assumed can indeed explain the truth of the basic laws of physics, to consider how those forms of matter make the principle of the conservation of energy true. The ontological explanation is not as simple as it may seem.

It may seem that the principle of the conservation of energy is an immediate consequence of the conservation of matter, because it is usually assumed that mass and energy are conserved separately as long as no nuclear reactions, converting rest mass to energy, occur in the region. The total quantity of matter that exists as energy in the region cannot change, because when the total rest mass does not change, matter does not exist in any other forms and matter does not come into existence or go out of existence.

However, the principle of the conservation of energy is not so simple ontologically, because given our ontological explanation of the nature of potential energy, there is a conversion between rest mass and kinetic energy (or other forms of actual energy) whenever potential energy is being consumed or created, which happens in most ordinary physical processes.

Material objects exert forces that can accelerate material objects, and our theory is that those forces are a form of matter that helps make up the material objects and whose quantity is counted in their rest masses. When potential energy has given the objects kinetic energy, for example, the objects have not only changed their relative positions, but the force field itself has changed. The change in the force field means that less matter is required to constitute it, and that is the source of the kinetic energy, which on our theory is also a form of matter. Thus, it is a conversion of some of the matter counted as rest mass into matter that is counted as kinetic energy. The opposite conversion occurs when kinetic energy becomes potential energy, and the same principle holds for conversions between potential energy and photons (and other forms of matter). Thus, the conversion between potential energy and kinetic energy does not violate the principle of the conservation of mass and energy.

Even though, in these processes, matter is being converted between a form that is counted as rest mass and a form that is counted as kinetic energy, the total quantity of energy does not change. The reason is that potential energy is counted as zero when it is maximum and that any potential energy that is consumed as kinetic energy (or photons) is counted as a bit negative energy in the region. There can be no such thing as negative matter, since matter is a substance. But counting potential energy as negative energy keeps the energy accounts balanced.

Negative potential energy is explained ontologically as a decrease in the rest masses of the material objects. The “rest mass” of a material object is defined, according to our ontological explanation of physics, as its mass when it is at rest in absolute space and the only force field in its neighborhood is the one that it imposes by itself (that is, separate from other material objects).

Thus, when it is (falsely) assumed that the rest masses of the objects involved are unchanged, counting potential energy as negative energy keeps the total quantity of mass and energy the same. The actual loss of mass from the total quantity of rest mass in the region is so small (according to Einstein’s equation, E = mc2) that the change in potential energy is not easily detected as a change in rest mass. Thus, counting potential energy as a negative quantity makes it seem that energy is conserved separately from rest mass in these processes.

But in fact, rest mass is not conserved. An object’s mass changes as its potential energy is actualized. Only the total of mass and energy are conserved even in most ordinary processes (where an object’s mass apart from its kinetic matter is accurately determined by subtracting the potential energy it has given up from its rest mass).

Thus, whereas the conservation of matter is an ontologically necessary global regularity, the conservation of energy is ontologically necessary only on the condition that matter has a nature that makes the basic laws of physics true, and thus, this shows it to be ontologically necessary only in spatiomaterial worlds like our own.

Material Global Regularities.The second law of thermodynamics, like the first, is stated as a regularity about the change in a total quantity that holds of closed region of space: the total entropy cannot decrease, though it may increase and usually does until it is maximum. It is also possible to explain the second law of thermodynamics ontologically, given that matter obeys the basic laws of physics. Once again, it an ontological effect that space has on the world because space, like matter, is a substance enduring through time and it contains all the bits of matter. Unlike the explanation of the conservation of matter, however, the explanation of the law of entropy depends not only on the principle of local motion, but also on matter having the more specific nature described by the laws of physics, whose truth was explained in Contingent laws. The reason is that there are geometrical aspects about the various forms of matter involved, and thus, not only does the wholeness of space require that all their local changes add up over time, but the structure of space requires the motion and interaction of the bits of matter to add up in a certain way geometrically.

The first and second laws of thermodynamics. The spatial and material global regularities made their appearance in physics as the first and second laws of thermodynamics. These laws were originally formulated to describe certain phenomena that were discovered in the development of steam engines. Physicists knew that steam engines could extract mechanical work from heat energy, but when they recognized that the total energy in a closed system does not change (the first law of thermodynamics), they had to admit that only some of the energy in such a system could be used to do mechanical work, for a closed system could change in ways that make it unable to do work. They knew that what makes it possible to extract mechanical work from the energy contained in such a system is a flow of heat from high temperature regions to regions with a lower temperature. The energy that is available to do work was called “free energy” (or “usable mechanical energy”). Thus, they recognized that, although the total energy in a closed system does not change, the free energy does. The free energy can decline and usually does. A quantity was introduced as a measure of the portion of the total energy in the system that could not be used to do mechanical work. They called it “entropy”. Thus, in these terms, the second law of thermodynamics holds that the entropy in any closed system never decreases. It may increase, and usually does, stopping only when it becomes maximum. But it never decreases. What decreases as entropy increases is free energy. The notion that there is a form of energy that declines, even though energy is conserved, was puzzling. And though it was discovered by thinking about steam engines, the second law of thermodynamics was eventually recognized to hold for systems of all kinds. The law of entropy increase is universally true, holding everywhere (except possibly for the origin of the universe in a big bang or the alternative to the big bang to be proposed in Cosmology).

The free energy available in a system has something to do with “order”, but it has never been very clear what order is in general or how it makes energy free.xlix In the case of steam engines and heat engines generally it is clear what the relevant order is. It comes down to the temperature differences between parts of a system and the quantities of heat each contains, for the flow of heat between them is what makes it possible to extract mechanical energy. But when the law of entropy is generalized to cover systems of all kinds, it is less clear what the nature of the order is.

It is, however, possible to explain order of all kinds in an intuitively clear way, if we take the wholeness of space into account as an ontological cause of global regularities, along with matter as contained by space. Energy is, in our terms, a form of matter, the same stuff that accounts for the rest mass of material objects, though there are several, basically different forms of energy—kinetic energy and the energy due to forces, both potential and actual (especially, photons). What makes energy free is, as we shall see, a geometrical aspect of these forms of matter and how they are contained in a region of space, for there are regularities about how such geometrical properties change over time. Showing that these global regularities follow from spatiomaterialism is, therefore, an ontological explanation of why the first and second laws of thermodynamics are true. It will require not only the material global regularities, but also the structural global regularities (to be discussed next). However, not only will that prove their ontological necessity, but it will also make clear what these regularities are all about in their full generality, including the way in which free energy depends on order.

Two global regularities are involved in making the second law of thermodynamics true according to this ontological explanation. The first is the tendency of potential energy to become kinetic energy or photons (or the tendency toward kinetic energy), and the other is the tendency of dynamic processes to become random (or the tendency toward randomness). Both are ways in which the specific nature of matter works together with space as an ontological cause to constitute a global regularity. But they work together, because the first is usually the source of the situations in which the second global regularity is exhibited. Let us consider each in turn and then see how they are combined.

The tendency toward kinetic energy. The first global regularity included in the second law of thermodynamics is the tendency of potential energy to become kinetic energy (and photons). The very name, “potential” energy, suggests this tendency, because potential energy is actualized by becoming kinetic energy (and/or photons). Though it is also possible for kinetic energy to become potential energy, the tendency is toward kinetic energy, because potential energy that has become actualized is less likely to restore itself. In order to see why, we need only contrast the natures of potential energy and kinetic energy. The same kind of contrast also shows that potential energy tends to be lost to other kinds of energy, such as photons, but to keep it simple, let us focus on kinetic energy for now.

When potential energy becomes kinetic energy, the kinetic energy comes from the forces that material objects exert on one another. According to our ontological explanation of the basic laws of physics, potential energy is actually a form of matter that constitutes the force fields themselves (and whose quantity is already counted in the rest masses of the objects exerting the forces). A force is called a field because its (potential) effects are distributed in the space around the object imposing the force, with a geometrical structure centered on the location of the object. That force field is explained ontologically by a form of matter that coincides with all those parts of space at once, and thus, the matter has a geometrical structure. The matter making up the force is spread out continuously in space, varying with the strength of the force it exerts. That geometrical structure means that there is a wholeness about the energy when is still potential, because each part contributes to the total potential energy (and, thus, to the total rest mass of the material object exerting the force) by having a definite location relative to every other part.

Kinetic energy, by contrast, is a form of matter that is not only attached to the material object, but also located at its center of mass. Kinetic matter, as we are calling it, has a location that enables it to connect the material object to space in a way that makes the object move across space in some direction at a certain speed. But that means that kinetic energy (or kinetic matter) lacks any inherent geometrical structure, except for the location of the object and its direction in the region where it exists.

Given that potential energy has an inherent geometrical structure and that kinetic energy does not, we can see why there is a tendency of potential energy to become kinetic energy in the motion and interaction of material objects by considering what is involved in the conversion between them. In order to convert potential energy into kinetic energy, more than one material object must be involved, because kinetic energy is actualized as material objects are accelerated by the forces they exert on one another. Such acceleration can occur only when the objects are spatially related so that the forces they exert on one another are able to accelerate them, and when they are a source of much energy, they are rather special. Objects at rest, for example, can acquire kinetic energy from attractive forces only when they are separated by a distance that can be closed by their acceleration (and they can acquire kinetic energy from repulsive forces only when they are located near one another and can move away). When objects are accelerated, however, the objects change their locations in space, and that changes the capacity of the force to accelerate them, because it decreases the special kind of spatial relationship needed to accelerate them. The potential energy has been consumed, and in its place the objects have some kinetic energy. The kinetic energy actually comes from the matter constituting the force field, and that is possible because the force field itself has changed in a way that requires less matter to constitute it. Thus, what has happened is that some of the matter that had an inherent geometrical structure has been extracted and has become matter that is located with the objects’ centers of mass. The matter’s loss of inherent geometrical structure is what is responsible for the temporally asymmetric tendency, for that makes it a form of matter that can be divided up among many other material objects as they interact. In particular, according to Newton’s laws of motion, when an object with high kinetic energy interacts slower moving objects, some of its kinetic energy is carried away by the other objects, being divided up among them.. It is not very likely that other objects will ever move in just the right ways to restore the special spatial relation that accelerated the object in the first place.

For example, if an object falls toward a planet because of the gravitational forces they exert on one another, it loses its potential energy as it approaches the planet and it gains kinetic energy. But as it collides with other material objects, either on its way down or when it runs into the earth, it gives up kinetic energy, and though it may rebound, much of its kinetic energy will be lost to other objects (and to overcoming the forces that may be involved in its fragmentation or deformation). The system will never restore the object’s potential energy.

To be sure, the conversion can work the opposite way. When objects exerting forces on one another have accelerated one another and lost potential energy, they have also acquired kinetic energy, and that can restore potential energy. Objects with kinetic energy restore potential energy when their retreat from one another is slowed by attractive forces (and when their approach to one another is slowed by repulsive forces). Indeed, a system involving only two material objects may simply go on converting energy between kinetic and potential forms indefinitely, such as a planet in an elliptical orbit around its star.

The reason there is a tendency toward kinetic energy is that other material objects are usually involved. According to Newton’s laws of motion, when objects with kinetic energy interact with one another, they exchange kinetic energy in a way that tends to equalize the kinetic energy among them. Thus, objects with unusually large amounts of kinetic energy see their kinetic energy divided up into smaller bits of kinetic energy that subsequently move around separately from one another. Kinetic energy is no longer moving objects in the right locations in the right directions at the right times to restore the unusually large potential energy from which it derived.

For example, even in a pendulum, which continually converts potential energy to kinetic energy and back again as it rises and falls in the gravitational field, this tendency to kinetic energy cannot be avoided. The bob also loses kinetic energy as it collides with particles of air and as it stretches and relaxes its tether, and it never restores all the potential energy and eventually comes to a stop.

There are, of course, processes in which kinetic energy and potential energy are continually being converted into one another, such as those involved in elastic collisions or a plasma of charged particles, but the potential energy in those processes is not a source of free energy, but just part of a random interaction that is the subject of the other global regularity, as we shall see.

The wholeness of the space containing the objects and their two forms of energy is what requires all the motion and interaction of bits of matter in the region to add up over time. That is how space causes all the global regularities. But in the case of the tendency to kinetic energy, space plays an additional role, which depends on its geometrical structure. There is a geometrical structure inherent in potential energy, and since it is superimposed on the uniform structure of space, there is a geometrical aspect to how the motion and interaction of the material objects adds up over time. A region with a large amount of potential energy must have a rather special geometrical structure, because potential energy exists in the forces that objects exert and it can be converted to kinetic energy only when objects have kinds of relative locations in the force fields they impose that can accelerate them. There is a tendency to kinetic energy, because when it becomes kinetic energy, is a form of matter that is located with the center of the material object’s rest mass, thereby losing that kind of its geometrical structure inherent in potential energy. It moves across space with the material object and can be transferred to other objects by collisions, which tends, as we shall see, toward randomness. Thus, the geometrical structure inherent in potential energy tends to be erased from the region.

In other words, when potential energy becomes kinetic, matter that did exist as part of the whole force field surrounding the material objects comes to be kinetic matter located with their centers of mass, and that makes it possible for the matter to be divided up further by collisions with other material objects. Once the matter is divided up, it is unlikely that the objects will have just the right speeds in the right directions at just the right locations and just the right times to put the objects back in the same spatial relation that gave them potential energy in the first place. Indeed, it is unlikely they will put any object in any similar significant source of potential energy, for that would require assembling separate bits of matter as a form of matter (a force being exerted) whose inherent geometrical structure is testimony to its unity as a single bit of matter.

The examples used here are based on gravitation,l but it should be noted that the same holds for electromagnetism and short range forces. When protons are combined randomly with electrons, their long-range attractive forces bind them together as hydrogen atoms, and though the potential energy may take the form of photons, instead of or as well as kinetic energy, the photons also lose their energy as they are scattered by other objects with electric charges and the geometrical structure inherent in potential energy is still broken up into many smaller bits.

Much the same happens in the case of short-range forces, though the spatial relations required to actualize potential energy are different. In nuclear fusion reactions, for example, nuclei must collide with enough energy to overcome an initial repulsion by the strong force, for otherwise the short-range attractive force does not reach far enough to bind them together.

Likewise, atoms (or groups of atoms) that exert attractive forces on one another may be separated too far by the molecular structures of which they are parts for their forces binds them together, until the local temperature is high enough for collisions to put them momentarily within the effective range. This is what happens when a match is used to start combustion.

Likewise in fission reactions, the potential energy of repulsion between clusters of positive charges in a heavy nucleus becomes kinetic when they fly apart, but first the nucleus must be made unstable by the absorption of a neutron.

In these cases the geometrical structure inherent in potential energy is more internal to the material objects, but that structure is still part of the geometrical structure of matter in the region, for there must be conditions in the region that will release it.

The tendency toward randomness. What tends to become random is the motion and interaction of bits of matter in a closed or isolated region, or what may also be called “dynamic processes.” In the dynamic processes used to think about this phenomenon, material objects are assumed to have repulsive forces by which elastic collisions keep them from occupying the same places at the same time.

In elastic collisions, material objects keep moving and interacting, because no kinetic energy is lost or absorbed by their parts when they interact. Force fields and conversions to potential energy are actually involved in these interactions, but they can be ignored here, because there is no net change and we want to consider what happens to their kinetic energy and other properties of the kinetic matter attached to material objects.

The traditional model for the tendency to randomness is the motion and collisions of billiard balls in a box. Once again, it is being contained by space that requires their motion and interaction to add up over time, and all that is needed to see why there is a tendency to randomness is to consider how motion and interaction in accordance with Newton’s laws of motion add up in space over time. There is, once again, a geometrical structure about the region that gets wiped out.

In a spatiomaterial world, everything happens by the motion and interaction of bits of matter, and in this case, it is extremely simple, because the bits of matter are all material objects with rest mass and kinetic energy (that is, the kinetic matter attached to material objects). There is no geometrical structure about the material objects in the region except their locations, speeds and direction of motion. These three properties are the initial conditions that would have to be described along with Newton’s laws of nature, according to the D-N model of explanation, in order to predict and explain what happens. They are all part of the efficient cause that determines what happens in the region. But it is not necessary, or even relevant, to derive mathematically what happens in detail in particular cases. If we consider the material objects relative to the space that contains them, we can see why their motion and interaction becomes randomized before long, if they aren’t already, because it is due to a geometrical aspect that we can understand, when we see them against the background of space.

The wholeness of space is what requires the motion and interaction of the bits of matter located in the region to add up as time passes, but the structure of the space within the region is what determines how the local changes add up. The objects have locations, speeds and directions at any moment that determine a geometrical structure relative to space, and when they move and interact according to Newton’s laws of motion, local changes add up in space over time in a way that erases that geometrical structure by evening out the spatial distribution of all three of the kinds of efficient causes that are relevant.

This tendency can be seen in each of the kinds of relevant efficient causes. That is, (1) the rest masses of material objects become spread out evenly throughout the region of space, (2) their kinetic energies become evenly distributed in space, and (3) their directions of momentum also tend toward an even spatial distribution.

(1)   If there are more material objects moving and interacting in one part of the region of space than in another, as when a gas of molecules is released in a vacuum, they will spread themselves out, because, other things being equal, objects at any boundary between highly and lowly populated regions are more likely to be turned back by collisions on one side than on the other. Hence, material objects will tend to move toward the less populated region until they are all evenly distributed in space.

(The diffusion of the molecules of one gas or liquid that is released into another works similarly, because when the objects colliding have different rest masses, the directions of the motion of less massive objects tend to change more, until the more massive objects are evenly distributed among them.

(2) Randomness may still not prevail, however, when rest masses are evenly distributed in space, because objects in some areas may be moving faster than those in other areas, for example, when there are hot spots or cold spots in the region. However, such spatial unevenness in their kinetic energy is also evened out, because elastic collisions of slow-moving with fast-moving rest masses tend to speed up the former and slow down the latter. That is the only what that both kinetic energy and momentum can be conserved. Kinetic energy tends to be divided up among the colliding objects. Thus, at the boundary between regions of different temperature, symmetrical elastic collisions will be so located and oriented in space that kinetic energy is communicated to the less energetic regions (that is, by conduction of heat).

(3) Motion and interaction may still not be random, even when rest masses and their kinetic energies are distributed evenly in space, because their speeds may be mostly in the same direction, as in a wind. But any such unevenness in the distribution of direction of motion among the objects also tends to be evened out, because when kinetic energies are evenly distributed within and outside the wind (their temperatures are the same), the wind tends to be invaded by objects moving perpendicularly to it. Objects making up the wind have more of their kinetic energy tied up in moving in the direction of the wind than objects outside the wind, and thus, objects approaching the wind perpendicularly are less likely to be turned back by collisions than those traveling in other directions (that is, the pressure exerted sideways by molecules of the wind will be less than elsewhere in the region, called the Bernoulli effect). As molecules invade the wind, they collide with molecules making up the wind, which tends to make their directions more perpendicular to the wind, and such reactions are more likely until the directions of momentum of all the objects in the region are evenly distributed.

The result is that the rest masses of the objects, their kinetic energies, and their directions of motion all tend to become evenly distributed in the region. That is the tendency toward randomness, and this distribution can be described statistically. But since heat is just the kinetic energy of the molecules in these simple cases, it is a tendency of kinetic energy to become evenly distributed heat, equalizing the temperature everywhere.

This tendency continues to hold when we take various complications into account. For example, collisions among real molecules are not necessarily elastic, because they can absorb some of the kinetic energy being exchanged. But as the kinetic energy is evened out among the objects, so is the energy absorbed by their parts.

And though material objects also emit and absorb photons, the spatial distributions of the locations, directions, and energies of the photons in the region also tends to be evened out by their interactions with the material objects, assuming that photons are reflected back and the region is closed. There are no kinds of interactions that can prevent the randomness.

The tendency toward randomness is that aspect of the law of entropy that is described as heat flowing from regions of high temperature to regions lower temperature, like water from high altitudes to lower altitudes. And since kinetic energy is a form of matter, according to this ontological explanation, it can even seen as vindicating the belief that heat is a “caloric fluid” that exists in addition to the rest masses of the objects involved. It is a form of matter that flows from hot regions to cold.

There is nothing very original about this explanation of the tendency to randomness. These effects are obvious to anyone who thinks about concrete examples of this tendency. What is new is recognizing that the tendency depends not only on the nature of matter (that is, the basic laws of physics), but also on the nature of the space with parts of which all the bits of matter coincide.

Our ontological foundation entitles us to take space into account as an ontological cause in explaining regularities about change. The wholeness of space is what requires the motion and interaction of all the objects to add up over time, as in all global regularities. But how they add up over time also depends on the structure of space, for it is only against the background of space that the causally relevant factors determine a geometrical structure.

It is the lack of evenness in the spatial distribution of one or more of the relevant efficient causes (their locations, kinetic energies, or directions of momentum) that makes the state non-random. And in each case, a geometrical structure about the non-random state is what causes the tendency toward randomness. It is the structure of space that determines where their motions will lead them and which objects they will interact with next. And we have seen how the unevenness in the distribution of the causally relevant factors puts certain objects are in asymmetrical situations which will eventually even out the spatial distribution of these factors. Thus, the temporal asymmetry of the second law of thermodynamics is a result, not only of the basic laws of physics, but also of how the motion and elastic collisions of material objects obeying those laws add up over time because they are contained by space.

Thus, when we take space into account, there is no mystery about why there is a temporal direction to change in which the kinetic energy of objects in non-random states winds up as heat evenly distributed in the region. The geometrical structure involved in any unevenness about the distribution of the three relevant factors is what causes those aspects of matter to become evened out in space, that is, more like the structure of space containing them.

The second law of thermodynamics.This ontological explanation of the second law of thermodynamics reveals that two different global regularities are involved: a tendency of potential energy to become kinetic energy (and/or photons) and a tendency of kinetic energy (and/or photons) to become evenly distributed heat. In both cases, there is a geometrical structure about the region that tends to be wiped out by how objects move and interact. One is the geometrical structure that the region has because it contains the geometrical structures inherent in the potential energy of forces (which can become kinetic energy). The other is the nonrandom distribution of causally relevant factors in the region (which tends toward the randomness of evenly distributed heat). Both kinds of geometrical structures tend to go out of existence, as we have seen, because that is how the motion and interaction of the bits of matter adds up over time because of the uniform structure of the space containing them. In one case, when the energy of position becomes energy of motion, matter with an inherent geometrical structure is replaced by a form of matter that can be broken up into different pieces. And in the other case, when any of the causally relevant factors is unevenly distributed, that is a geometrical structure in the region that tends to wipe itself out over time, with kinetic energy winding up as heat evenly distributed in the region. When geometrical structures of either kind go out of existence, only very special situations can bring them back into existence. And these two tendencies are connected, because the tendency to kinetic energy supplies nonrandom dynamic processes that tend to become random. Together, they make up a temporally asymmetrical change in the region as a whole.

Given how both global regularities involve the disappearance of a special kind of geometrical structure in the region as time passes, it may be useful to suggest that the law of entropy increase can be seen as a kind of four dimensional geometrical structure in the region as a whole. In its most complete expression, the geometrical structure inherent in potential energy becomes the geometrical structure inherent in nonrandom distributions of causally relevant factors, which in turn becomes the lack of any salient geometrical structure inherent in the randomness of evenly distributed heat. At the later edge of this four dimensional structure, the bits of matter have the kind of geometrical structure that is most like the structure of the space containing it. It is as if matter in the region were coming to mirror the uniform structure of space.

This explanation of the second law of thermodynamics solves a puzzle about the reduction of the second law of thermodynamics to physics. The law of entropy seems to resist reduction to the laws of physics, because it describes a regularity about change that is asymmetrical in time, whereas the laws of physics describing how the material objects interact are all time-symmetrical. The temporal asymmetry of the law of entropy comes, however, not from the laws of physics by themselves, but from the forms of matter they describe having geometrical aspects that are casually relevant in how local changes adds up in space over time. Both tendencies involved in the explanation of the law of entropy are a result of how geometrical structures about the matter involved are efficient cause of their own extinction. That solves the problem. (See Change: Epistemological philosophy of causation: Second law of thermodynamics.)

The thermodynamic flow of matter.If we look at the second law of thermodynamics in terms of matter, the two tendencies can also be seen as a “thermodynamic flow of matter” from potential energy to evenly distributed heat. This is a flow of matter in a certain “direction” through a series of forms of matter. The matter starts off as part of the rest masses of the material objects involved, for matter in that form is what constitutes the forces that the objects exert on one another. When the objects have spatial relations in which their forces can accelerate one another, it is potential energy. And when potential energy is actualized, the matter takes the form of kinetic matter, which lacks any inherent geometrical structure, since it is a form matter that is located at the material object’s center of mass. And since interactions among material objects tend to equalize their kinetic energy (and other causally relevant factors), kinetic matter tends to become randomized as heat and evenly distributed in space as heat. Since matter flows through these forms in only one direction, however, matter winds up as evenly distributed heat, that is, with higher entropy in the region.

This thermodynamic flow can also involve potential energy becoming photons, but they are merely another route to evenly distributed heat. The photons interact with the material objects and become randomized for much the same reasons.

This is to characterize the global regularities described by the second law of thermodynamics as if the processes followed a direct path to evenly distributed heat of increasing entropy. But the thermodynamic flow of matter may include twists and turns in which some of the kinetic energy becomes potential energy in other forms only to be released again as kinetic energy before finally turning into heat that is then evenly distributed in space. As we shall see, such transformations between potential and kinetic energy are how machines use this kind of matter, as free energy, to do work. Similarly, though nonrandom distributions of the three causally relevant factors becomes evenly distributed heat, it may be used as free energy to do work, as in heat engines, which may create potential energy and give some objects high kinetic energy, before it becomes evenly distributed heat. These complications will be considered when we take up structural causation.

The transformation of free energy into entropy.To sum this up in more familiar terms, at the most general level, according to the second law of thermodynamics, what is happening in any closed or isolated region of space is the transformation of free energy into entropy. Free energy is all the energy in the region that has not yet become evenly distributed heat, where heat is simply randomness in the motion and interaction of the simplest physical objects that can move relative to one another. And entropy is, technically, a measure of how much of the total energy in the region exists in the form of evenly distributed heat. The second law of thermodynamics, or law of entropy, holds that in a closed or isolated system, entropy can increase, but it cannot decrease. That is, all the other physical forms of energy (that is, forms of matter) are ineluctably becoming evenly distributed heat.

This is the supposedly bleak image of a world made up of matter in motion which sees the universe as condemned to a “heat death.” This image has traditionally been used to discredit materialism, or at least discourage belief in it. But if we consider what it means more concretely at the scale of planetary systems, the transformation of free energy into entropy is, as we shall see, the fountain of everything valuable in the world. Free energy is what makes it possible for structural causes to do work, as we shall see next.

To talk of “free energy” is to classify energy by its capacity to be used by machines to do work, but concretely, such free energy takes many different physical forms. On the scale of a planetary system, the richest and most constant source of free energy is the star, because such a huge accumulation of mass has a gravitational field that contains an enormous amount of potential energy. The energy stored in its force field is the source of all the free energy that will eventually become evenly distributed heat (except for energy from radioactive decay). Its gravitational field constantly accelerates bits of matter toward its center. Even inside the star itself, the inward acceleration of more distant matter causes a pressure that is balanced against the kinetic energy (and photons) constituting the random motion and interaction of more centrally located particles and their electromagnetic interactions. Indeed, the kinetic energy is great enough for the collisions of protons, neutrons and small nuclei to bring them within the short range of the strong attractive force that they can exert on one another, and as it fuses them together, the potential energy of the strong force is actualized as kinetic energy and photons, decreasing their rest masses. High energy photons (and other particles) escaping at the surface of a star radiate outward toward cold, empty space, showing the surrounding planets. Since radiation is a form of free energy (like kinetic energy before it is randomized), it can be used to do work on the planets intercepting it. Not only do photons heat the planet, but they supply energy in a form that can drive chemical interactions. There is also heat from the tidal forces that planets orbiting a star suffer as they rotate on their own axis (and from the radioactive decay of particles making up the planets). The energy eventually flows through the planets, since planets also lose heat as they radiate energy into cold empty space in the form of lower-energy photons.

The star’s radiation is, therefore, a form of energy that can be used by machines on planets to do work, or free energy. This is the setting, as we shall see, for reproductive causation to generate its spectacular global regularity. But first we must consider how this thermodynamic flow can be used to do work, and that is an effect of structural causation.

Structural global regularities.Spatial and material causation are the most direct ways that space and matter impose regularities on change in whole regions over time. But they are not the only ways, because the forms of matter that explain the truth of the basic laws of physics are not the only kinds of substances that can coincide with space. The nature of matter also makes non-basic, or derivative substances possible, and they can work together with space as ontological causes to generate global regularities.

Though everything that coincides with space is made of matter, matter is capable of being organized into more complex material substances that move around in space and interact as units with other bits of matter, and the wholeness of space also requires their motion and interaction to add up in space over time. They are more complex ontological causes, and they add up in space over time to more complex regularities about the change that takes place in entire regions.

These more complex ontological causes are “derivative substances” (or “derivative ontological causes”) because they are constituted by the basic ontological causes, matter and space. Though they can endure through time like basic substances, they can also come into existence and go out of existence as time passes.

These more complex kinds of substances include not only material objects with unchanging geometrical structures, such as ordinary composite objects, from cups to automobiles, but also a more complex, temporally structured kind of process that is based on such material structures. The first is discussed in this chapter, and the second will be taken up in Reproductive global regularities.

In both cases, however, the derivative substances are ontological causes of global regularities, because they work together with space to cause change to be regular in entire regions by their continuous existence through time as (derivative) substances that coincide with some part of space or other in the region. Though the wholeness of space is what requires motion and interaction to add up in space over time, how their motion and interaction adds up in space over time depends on their natures as (derivative) substances as well as the structure of space. And as we shall see, they add up to complex global regularities about change.

Material Structures. Since material structures are just material objects with relatively stable geometrical structures, most ordinary objects are examples of them. They have geometrical structures that do not change in relatively wide ranges of interactions because they are byproduct of certain cases of the tendency of potential energy to become kinetic (one of the two material global regularities). Thus, they continue to exist in the region even when entropy is maximum. Though as we shall see, material structures can be constructed by machines using free energy to do work, that is just a more complex example of the structural global regularities to be explained. And the existence of material structures does not depend on such machines, because there are material structures that form naturally.

The best examples of such naturally forming structures involve the electromagnetic forces described by quantum field theory. It account for the formation of atoms (from nuclei and electrons), molecules (from atoms), and crystals, rocks and other natural material objects (from molecules). But similar explanations hold for the formation of the nuclei of atoms.

Material structures come to exist naturally because of the attractive forces that simpler material objects exert on one another. The exertion of attractive forces across space is a form of potential energy that can draw material objects together and bind them into relationships with one another that are stable and do not change. The stability of such composite objects comes from the parts giving up potential energy as kinetic energy (or radiation) when they form themselves into a unit, because, once united, their bonds to one another cannot be broken, unless subsequent interactions supply enough energy in the right form to make up for the energy that was lost forming the bonds. The improbability of that happening is, as we have seen, what causes the tendency to kinetic energy. (Kinetic matter and photons lack the inherent geometrical structure of potential energy, and thus, almost anything that happens to such matter will make it impossible for it to regain its initial geometrical structure as potential energy). But the quantum nature of the interactions helps account for their stability, because that means the objects can be freed from their embrace with one another only when enough energy is supplied by a single interaction (as illustrated by the photo-electric effect). Thus, such composite objects have geometrical structures that do not change even though they are interacting with other objects (as long as the energy of those interactions is not too great).

Thought material structures may seem to override the tendency to randomness, they are just byproducts of the tendency toward kinetic energy, the other global regularity involved in the second law of thermodynamics.

Material structures may seem to override the tendency toward randomness in two ways. Instead of interacting by elastic collision, the parts of composite objects exert forces that bind them to one another, and thus, instead of being spread out evenly in space, material objects are clustered together in the same local area. And instead of winding up with momentums in every which direction, the parts of such structures all have much the same direction, like a wind with fixed parts. In other words, instead of being a gas or liquid, they are a solid state of matter, which moves and interacts as a whole.li

But instead of overriding the tendency to randomness, they exemplify the other material global regularity that is covered by the second law of thermodynamics. The existence of material structures is part of the price that is paid to have kinetic energy that can become randomized as evenly distributed heat. It is the loss of potential energy (which is actually a loss of rest mass) that binds the parts into stable geometrical structures. Their formation is part of the process of free energy becoming entropy.

Composite material objects with unchanging geometrical structures are the derivative ontological causes that will be called “material structures” or “structural causes”. But it should be noted that not all objects that form naturally as byproducts of the tendency of potential energy to become kinetic energy are material structures, and the main exceptions, not surprisingly, result from gravitation.

Stars form as a result of gravitation, but these “composite objects” do not have unchanging geometrical structures in this sense. Gravitation concentrates material objects in certain locations, and though this is a deviation from the tendency of rest masses to be distributed evenly throughout space, the forces are so great, when enough matter is concentrated at some location, that material objects continue to move and interact randomly with one another, as a plasma of nuclei and electrons (a fourth state of matter, besides solids, liquids and gases). This gives stars only the minimal geometrical structure required to speak of them as composite objects at all. They approximate a sphere, but since there are no unchanging spatial relations among particular parts that would give the whole a geometrical structure that remains stable as it interacts with other objects in space, they are not structural ontological causes. Though planets and smaller astronomical bodies do acquire unchanging geometrical structures from gravitational attraction, they also depend on the parts forming bonds based on electromagnetic forces.

If gravitational acceleration is explained by the acceleration of the ether, then the nature of the gravitational force would explain why stars are different from objects that depend on other forces. Material objects that are clustered simply because of the ether (by which they coincide with space) accelerating them towards one another do not necessarily form bonds with one another. By contrast, the interactions on which other kinds of composite objects are based involve either opposite forces of attraction and repulsion canceling one another out (as in electromagnetism) or are short range forces (as in the weak and strong forces), and they all have a quantum nature which helps makes the structures they constitute stable.

It should be noticed, however, that even some composite objects formed by forces with a quantum nature lack unchanging geometrical structures. For example, water molecules interact by weak electromagnetic forces, called “hydrogen bonds”, but when water forms into a drop, the molecules continue to move relative to one another as they interact, resembling to some extent star-like gravitational objects on a small scale.

Reversible processes. The existence of material structures depends on the specific nature of the matter that helps constitute the actual world, and when they exist, the wholeness of the space containing them causes their motion and interaction in any region to add up over time as regularities about entire regions of space. But since they have a geometrical structure, how they add up also depends on the structure of space. Though the new global regularity is rather simple by itself, it makes all the difference in the world, as we shall see, when combined with material global regularities, that is, free energy, for that is what constitutes irreversible processes.

What is regular in the case of reversible processes is not just that the geometrical structure of the material object does not change. That is a property of the composite object, rather than a property of region as a whole. But since its geometrical structure does not change over time, there is a geometrical structure about the dynamic processes in the region that does not change, and that is a global regularity. In other words, material structures contribute to the geometrical structure of the region in much the same way that potential energy does, by its inherent geometrical structure. The difference, of course, is that the material structures do not lose their geometrical structure as potential energy tends to do as it becomes kinetic.

As long as the composite object’s geometrical structure does not go out of existence, it is like a new kind of material substance, which is not mentioned by the basic laws of physics. Indeed, the reason material structures are ontological causes is that, like space and more elementary forms of matter, they exist continuously over time like substances. And since change is just an aspect of substances enduring through time, material structures cause change to be regular by helping constitute the process. As in all ontological explanations, that is how the essential natures of substances help determine the nature of what is found in the natural world. Material structures are unchanging aspects of the substances making up the region as time passes.

Material structures cause a global regularity, because as they move and interact as particular substances in space, their geometrical structures help determine, along with the structure of space and the other bits of matter in the region, how change occurs as time passes. Though everything happens by efficient causation, the motion and interaction of material structures with other bits of matter must add up over time in space. The kind of global regularity that material structures add up to is simple. It is just the existence of the material structures in the region moving and interacting with other bits of matter. And material structures with different geometrical structure impose different regularities on how geometrical structures of whole regions change over time.

Though the wholeness of the space containing all the bits of matter is what makes their motion and interaction add up over time, how the motion and interaction of material structures adds up over time depends on the structure of the space containing them.

In the first place, the uniform structure of space makes it possible for composite objects to move without changing the spatial relations among their parts. Every local area in space has a geometrical structure that can contain any specific kind of geometrical structure that composite material objects may have.

Second, when such objects do interact, space allows what happens to depend not only on the forces that the objects exert on each other (by way of the forces exerted by the parts of such geometrical structures), but also on how their geometrical structures fit together. This is a geometrical aspect about how material objects in the region interact with one another that cannot even be simulated by forces.

Material structures can, therefore, be said to structure dynamic processes. Thus, structural global regularities of are “structured dynamic processes”.

Even though structural global regularities may be little more than the existence of material structures in the region, there is no doubt that the existence of such geometrical structures in the region imposes a regularity on change in the region. It can be seen in how round pegs, but not square pegs, fit into the round holes in a board, how rings linked with one another act like a chain, or how molecules can be confined in a box.

Consider, for example, a box of gas that is part of a larger (closed) region of space. Although the molecules are not bound to the box and move around independently of it, those on the inside never get outside, while the molecules on the outside never get inside. This is because the box has a geometrical structure that, together with the structure of space, leaves no route for molecules to move from one region to the other. The gas molecules are not equally likely to be located in every part of the region, and as the box moves around in the region, the structure about the distribution of matter in the region changes in a regular way, because the otherwise randomly moving molecules always move around inside the box. The dynamic process taking place in that region has, therefore, a geometrical structure that does not change over time.

The part-whole relationship in the box-of-gas example suggests a more general point about material structures and the global regularities they and space generate: the unchanging geometrical structure of a composite object as a whole constrains the motion and interactions of its parts, and that generates (regular) behavior in the object as a whole. This is, perhaps, obvious in complex machinery, but consider a simple example, two rings linked together. The rings can move and interact independently of one another to some extent, but their locations are not random, because they can move only within limits which are imposed by the geometrical structure of the object as a whole. This further geometrical structure about what happens to the rings is a kind of global regularity about change over time that might well be called the “behavior” of the object as a whole. The behavior of chains of many such linked rings is quite useful in communicating forces from one place to another. The notion that the whole controls the part is sometimes thought to entail a holism that is incompatible with materialistic reductionism, but when we recognize that the substances constituting such objects include space as well as matter, a regular behavior on the part of the whole is just what is expected.

Structural causation introduces a complication into the ontological explanations of spatiomaterialism, because material structures are derivative ontological causes. In order to be ontological causes of the global regularity about change, they must endure through the whole period. But over longer periods of time, material structures do come into existence and go out of existence. In speaking of them as ontological causes, we are treating them like substances, which have essential natures, that is, properties that hold at each moment of their existence and help determine how contingent properties come and go over time. But since they are derivative ontological causes, we must take into account their “generation” and “corruption”, much as Aristotle did in explaining his very different kinds of substances with essential forms. They are analogous to the various, interconvertible forms of matter we distinguished in order to explain the basic laws of physics ontologically, except that we can explain the generation and corruption of material structures from simpler substances by their motion and interaction in space according to the basic laws of physics. However, the advantages of introducing this complication far outweigh the disadvantages.

Many puzzles are cleared up by recognizing that material structures are ontological causes.

It settles, for example, a question about the criterion for the identity of ordinary objects over time that arises for epistemological philosophers. Material objects are commonly classified by their geometrical structures, and some epistemological philosophers (Hirsh 1982, p. 134) rely on it so heavily that they are tempted to believe that simply having the same kind of geometrical structure at a later moment would be sufficient for its identity—even if the object were to vanish from one location at one moment and were to appear somewhere else the next. That is not a case we need to worry about, since it is not even possible according to our ontology. But the recognition of material structures as ontological causes can solve puzzles about identity posed by epistemologists who pit having the same geometrical structure against spatio-temporal continuity.

Nozick (1981, p. 29ff), for example, considers the case of Theseus’ ship, which is rebuilt, plank by plank, over a period of time. One would ordinarily claim that what results from the rebuilding is the same ship, although none of the parts is the same. But Nozick poses a further question by supposing that each of the parts of the original ship is saved and later used to reassemble the original ship. He asks, which later ship is identical to the original ship. Nozick’s answer is the “closest continuer theory”, which has intuition deciding in each case (and for each person) which is closest. But if we recognize how global regularities depend on ontological causes, it is clear which ship is identical to the original ship, because only one of them has an unchanging geometrical structure that can cause change to be regular by existing continuously over all that time as a substance. Its role as an ontological cause determines its identity over time.

The recognition of global regularities solves various problems about the irreducibility of less general laws in science to the laws of physics, as we shall see in Epistemological philosophy of causation. The general form of the problem can be seen in the case of structural global regularities. Science tends to overlook this explanatory role of material structures, because it its looking for efficient causes, not ontological causes. The only relevant factors involved in efficient-cause explanations, besides the laws of physics (and mathematical theorems), are initial and boundary conditions. A structural cause is not just an initial condition (although it can be inferred from initial conditions together with the relevant laws of physics), because it causes by its continuous existence over the whole period of time that the global regularly occurs. To be sure, boundary conditions also cause by persisting through the period of the regularity. But structural ontological causes are not boundary conditions, for they are not just a condition about the system’s limits in space (how it is related to or isolated from the rest of the world). Thus, structural ontological causes tend to fall through the cracks. That is not to say that they are ignored. It is rather they are implicit in efficient causes that are recognized. The familiar deductive-nomological model of explanation has no way to acknowledge the distinctive kind of role that material structures play as ontological causes of global regularities.

Irreversible processes. Since structural global regularities are simply the continued existence of material structures in a closed or isolated region, they seem rather trivial. But structural causation can have more dramatic effects when it is combined with material causation. Since material objects coincide with space, their unchanging geometrical structures can fit together with the geometrical structures involved in the tendency toward kinetic energy and the tendency toward randomness, since the latter also coincide with space. In both tendencies, there are geometrical structures that are wiped out by how bits of matter move and interact. The inherent geometrical structure of potential energy is lost in the tendency toward kinetic energy, and the geometrical structure of non-random distributions of causally relevant factors is lost in the tendency to randomness. Material structures can channel the flow of matter through these geometrical forms, because their geometrical structures coincide with parts of the same region of space where these tendencies are exhibited. The reason that those tendencies are called “free energy” is that material structures can thereby channel the thermodynamic flow of matter from potential energy through kinetic energy to evenly distributed heat to to bring about states of those regions that would not otherwise occur. That is how machines use free energy to do mechanical work.

What makes it possible for machines to use free energy to do work can be explained ontologically, because we have already explained how material structures are ontological causes that structure the motion and interaction of other bits of matter in the region. Ordinary machines have unchanging structures that are large enough to think of them as ordinary macro-level material objects, by contrast to the micro-level objects mentioned in describing thermodynamic processes. Let us distinguish two ways that machines do work, depending on whether the free energy comes from the tendency toward kinetic energy or from the tendency toward randomness.

Free energy from the tendency toward kinetic energy. A machine has an unchanging geometrical structure as a whole that constrains how the parts of which it is composed can move and interact with one another. Potential energy also has a geometrical structure, and when the spatial relations among the forces involved combines with the unchanging structure of a material object, the tendency of potential energy to become kinetic energy can be channeled in ways that produce useful outcomes (although it often involves complex processes in which the kinetic energy is converted into other forms of potential energy and back again to kinetic energy in order to produce the kinds of changes that are desired).

This can be seen in a wide variety of cases. For example, the potential energy of gravitation can be tapped by water wheels and other structural causes, such as cog wheels, levers, wedges, and the like, to release kinetic energy in a way that grinds corn, weaves cloth, or does other mechanical work.

Free energy from the tendency toward randomness. The nonrandom distributions of efficient causes that wipe themselves out in the tendency toward randomness are made up of objects on the micro-level, but since the nonrandom distribution itself is a geometrical structure of the region as a whole, it can fit together with macro-level material structures to do mechanical work. Distributions of three kinds of efficient causes had to be mentioned in explaining the tendency to randomness (the rest masses, kinetic energies, and momentums of molecules), and we can find examples of machines using each of them.

The most familiar example involves the uneven distribution of kinetic energy. The difference in temperature between two, spatially-separated sets of material objects is what enables the steam engine to tap the free energy that exists in the flow of kinetic energy from hot to cold. The kinetic energy released by combustion of fuel flows across the wall of a box to water, producing steam at high pressure, and its expansion against a piston in a cylinder does mechanical work, such as propelling a train along a track. Internal combustion engines are as much heat engines as steam engines, although they eliminate the step in which the flow of kinetic energy conducts heat from the combustion of fuel to the water being heated by burning the fuel in the very cylinder where the piston is pushed.

The other two causally relevant factors whose uneven spatial distributions tend to wipe themselves out can also be tapped by structural causes to do work. The free expansion of a gas is used in jet propulsion, and the uniform direction of momentums contained in a wind can be caught by a sail to pull a boat along. In the latter case, it is even clearer that the free energy comes from the flow of matter through region-wide geometrical forms that is evening out the directions of momentum, for a sail can propel a boat across wind or, better yet, against it; the free energy comes, not just from going along with the wind, but from making the molecules’ directions of momentum more random. The same principle applies in wind mills and turbines.

In either case, whenever machines use free energy to do work, the geometrical structure of some material object engages with some region-wide geometrical structures involved in the tendency toward kinetic energy or the tendency toward randomness so that the thermodynamic flow of matter toward evenly distributed heat is structured to do mechanical work. The kind of work done depends on how the material structures coincide with the geometrical structure of the potential energy or the nonrandom distribution of causally relevant factors on the macro level in the region.

In some machines, both tendencies are involved. For example, the potential energy of the forces exerted at one location are communicated in hydraulic machinery by using the tendency to randomness in liquids confined in cylinders to transfer the kinetic energy and momentum from one location to another. Electrical machinery works by the same principle, except that the potential energy is communicated by freely moving electrons confined to conductors, and the work is usually done because of the magnetic forces set up by moving electric charges.

In sum, there are two kinds of global regularities caused ontologically by material structures, reversible and irreversible processes. What makes irreversible processes different is that what is being structured is a thermodynamic flow of matter (that is, motion and interaction in the region of a kind that is changing from potential energy to kinetic energy or in which a nonrandom distribution of causally relevant factors is wiping itself out). When there is no thermodynamic flow of matter toward evenly distributed heat, entropy is already maximum, and the global regularity is just a kind of geometrical structure that holds of the whole region over a period of time because some of the material objects moving and interacting there are composite objects with geometrical structures that do not change. That kind of global regularity was illustrated in the last section by the box of gas and the interlocked rings. Any change that takes place in such a region wide process could take place in the opposite direction in time. But when a thermodynamic process is going on in the region and a material structure uses its free energy to do mechanical work, the change that occurs in the region is temporally asymmetric. The work done depends on their being matter flowing through geometrical forms from potential energy to evenly distributed heat, and since some free energy is always lost to increasing entropy in the process of using it to do mechanical work, the change taking place in a closed system cannot return to its starting point.

Since reversible structural global regularities do not depend on material global regularities (except for how material structures are a byproduct of the tendency of potential energy to become kinetic), they are not included in the following diagram of the relationships among global regularities.

The essential role of space as an ontological cause of global regularities is confirmed by irreversible process, for it is what makes it possible to combine material and structural global regularities. This can be seen in the steam engine, the concrete phenomenon that led to the discovery of the second law of thermodynamics.

The wholeness of space plays the same role in all global regularities: it makes the motion and interaction of the bits of matter in the region add up over time. But the structure of space plays a further role in generating the material and structural global regularities, because there is a geometrical aspect to how the motion and interaction adds up as time passes. The regularity caused by material causation is that two kinds of geometrical structures about the region as a whole disappear, and the regularity caused by structural causation is that the region contains material objects whose geometrical structures do not change. In both cases, these geometrical structures are superimposed on the uniform structure of the space in the region, and that is what explains how these two global regularities can be combined, for it is simply a matter of how the thermodynamic structures fit together with the material structures.

Steam engines, for example, are just material structures combined with various thermodynamic processes in the same region of space. The free energy consumed by steam engines is kinetic energy that comes from combustion, that is, the tendency of potential energy in the fuel to become the randomized kinetic energy of heat. This kinetic energy is supplied where the material objects losing some of their rest mass are located. But since that happens in a part of steam engine, material structures can channel it to do work before the tendency to randomness evens out the nonrandom distribution of this randomized kinetic energy. It makes water in the boiler heat up, and as the spatial distribution of causally relevant factors tends to even out, and the momentum of the fast-moving molecules drives a piston in a cylinder, doing mechanical work, such as lifting a weight in a gravitational field. The way that the unchanging geometrical structures of composite material objects coincide in space with the region-wide geometrical structures that are disappearing due to the thermodynamic flow of matter toward evenly distributed heat is what explains how it is possible for heat engines to tap the free energy contained in such thermodynamic processes to do work, and that confirms the role of space an ontological cause in both kinds of global regularities.

Perpetual motion machines.These examples of machines doing work illustrate how material structures can combine with the free energy contained the thermodynamic flow of matter toward evenly distributed heat to produce changes that would not otherwise occur. But since machines can do work, it might seem that they could structure it in ways that would restore the free energy they are using. By returning kinetic energy to its potential form or imposing a new nonrandom distribution of causal factors on the dynamic process, structural causes would be doing work without entropy increasing, that is, without using up free energy. If the work done restored the geometrical structure containing the free energy it uses, it would be a machine that continues doing work forever, or a perpetual motion machine.

It is not, however, possible, because any machine that structures a thermodynamic flow of matter toward evenly distributed heat is itself part of a larger process in which such a thermodynamic flow is taking place. The machine itself is not exempt from the law of entropy increase, if only because some of the free energy becomes evenly distributed heat by flowing through the machine. The machine itself is just another part of a region where the material global regularity holds.

This can be illustrated by a pendulum swinging in a gravitational field, the example used to illustrate the tendency toward kinetic energy. The material structure constrains the motion and interactions of its parts so that the gravitational potential energy that the bob has at its maximum height is released as kinetic energy, and that kinetic energy is used to do the work of restoring it to its potential form. But it cannot go on forever, because the potential energy that is given up in each swing is never fully restored. When it is kinetic, the pendulum gives up part of its energy to other objects with which it interacts (for example, as it collides with molecules in the air and causes friction in the rope suspending it), according to the tendency of potential energy to become kinetic energy describes. And the tendency toward randomness means that the thermodynamic flow of matter through region-wide geometrical forms continues until the matter becomes kinetic energy on the micro level and winds up as heat energy evenly distributed throughout the region. Thus, the pendulum slows down and eventually stops swinging altogether.

Similarly, an elastic ball cannot bounce forever, using kinetic energy to exchange gravitational potential energy for the electromagnetic potential energy embodied in the ball’s deformation, because once the energy is released as kinetic energy, it is not fully restored.

More generally, free energy can be stored in machines, either as potential energy, kinetic energy on the macro level, or as cyclic transformations between potential and kinetic energy. But when energy is kinetic, interactions with other material objects divide up the energy until the energy is randomized on the micro level and, as heat, becomes evenly distributed throughout the region. Machines produce less free energy than they consume, because some of the thermodynamic flow of matter being channeled to do work flows directly through the machine itself toward evenly distributed heat in the region.

The ultimate randomization of kinetic energy depends, as we have seen, on three factors. The material structure itself resists the randomization of two of these factors, but there is one kind of efficient cause whose randomization it cannot resist. The unchanging structure of the composite object means that the rest masses of its parts do not become evenly distributed in the region. Moreover, since they move together as a composite object, the parts all continue to have much the same directions of momentum. But the parts can have different kinetic energies (such as vibrations within the forces holding them together), and kinetic energy does tend to become evenly distributed among them, for any inequality in the distribution of kinetic energy is a geometrical structure that tends to wipe itself out. This aspect of tendency toward randomness will continue until heat is evenly distributed throughout the region and everything has the same temperature.

There are, therefore, no perfectly efficient machines. Machines use free energy to do work, but as they do, some of it is inevitably lost as heat energy, which becomes evenly distributed in the region, increasing entropy in the region. The efficiency of a machine is measured by how much of that free energy is actually made to do mechanical work as that happens.

Examples of structural global regularities from nature.Using machines designed by humans to illustrate structured thermodynamic processes should not, however, keep us from seeing how structural ontological causes are responsible for global regularities found in nature. I will describe some of them here, because these varieties of structural causation will be used to explain how reproductive causation get started in planetary systems.

The unchanging structures of atoms are, for example, structural causes of the molecules that form naturally from them. The relevant geometrical structure of the atom is the number of electrons the nucleus can bind in the outermost shell. The ways in which the geometrical structures of the atoms and the forces exerted by their parts fit together geometrically explains why their motion and interaction add up over time in the structure of space to the formation of molecules, a composite object with a higher level of part-whole complexity. The free energy for their bonds comes from the forces exerted by their parts (the positive charges of the nuclei attracting the negative charges of the electrons), and since the potential energy released by their formation becomes kinetic energy (or radiation) that eventually becomes heat evenly distributed throughout the region, it is irreversible. The formation of molecules is, therefore, a naturally occurring irreversible structural global regularity.

In a similar way, the structures of the molecules can, in turn, be structural causes of yet higher levels of part-whole complexity. The formation of crystals involves the attachment of one molecule after another to a growing, regular geometrical structure.lii It is an example of structural causation, because the growth depends on how the geometrical structures of the molecules fit together with the crystal structure created by the attachment of the last molecule and how the forces exerted by corresponding parts affect one another. It is an irreversible structural global regularity, because it depends on the free energy supplied by forces exerted by their parts (often hydrogen bonds, which are weaker than those responsible for the molecules). And the result is a new kind of material structure. The kinetic energy released becomes part of the evenly distributed heat, and the bonds of the molecules making up the crystal cannot be broken without additional free energy, that is, unless enough energy is concentrated at just the right point at the right moment to free the molecule from its bonds to the crystal.

In living objects, more complex structures of molecules have more complex effects, such as the spontaneous formation of plasma membranes in water and of complexes made up of various protein molecules from their random motion and interaction. Plasma membranes are self-assembling structures used as barriers in biological processes. They are made of phospholipids, which are long, skinny molecules that tend to line up like matches alongside one another as sheets (because of weak, Van der Waals forces between them). The sheets form double layers in water (since their hydrophobic surfaces are pushed together), and the sheets tend to close on themselves in water to form spheres.

Similarly, protein molecules are amino acid molecules linked together like a chain (by peptide bonds), and the geometrical structures (or “conformations”) they take on in water often fit together in such a way that weaker forces between corresponding parts hold them together and make them stable.

Molecules have structural effects other than merely forming higher levels of part-whole complexity in material objects. They can act more like machines. For example, their structure can give them a behavior as a whole that produces another kind of material structure, which then serves a structural cause. This occurs in protein molecules, the long chains of various kinds of amino acid molecules that are the basic micro-level machines in living organisms. Such chains can bend at their chemical bonds so that weaker forces exerted by the various amino acids bind parts of the chain to one another, giving the whole chain a further geometrical structure as a whole. (That is, the unchanging structure of the protein molecule not only constrains the motions of its links relative to one another as they move in the water and determines how the chain can bend, but it also thereby determines which kinds of amino acids will be next to one another when it bends in certain ways and, so, where weaker bonds will form among the parts.) The resulting “conformation” of the protein is usually the relevant material structure that structures thermodynamic processes in living organisms. (The DNA molecule has a similar behavior as a whole: the structure of the molecule so constrains the motions of its parts relative to one another that DNA winds up as a double helix.)

Molecules can also be material structures that produce new material structures by acting on other molecules. They are called “catalysts”. But the most dramatic examples are proteins whose conformational structure makes them “enzymes”. Such proteins hold other molecules together and distort their shapes so that new chemical bonds form among their parts, replacing the old, and thereby producing molecules that are otherwise not likely to be formed at the prevailing temperature. Such molecular machines are responsible for the replication of DNA and the synthesis of proteins.

In DNA replication, proteins in conjunction with a DNA molecule are a structural cause that catalyzes a long series of chemical changes in other molecules so that another molecule acquires its structure. The geometrical structure of the DNA and protein molecules does not change, but it temporarily binds other molecules in a way that causes bonds to form in them. Each such structural effect leaves both the original DNA molecule and the copy being formed in a slightly different state, so that a different kind of molecule will interact with it the next time and the whole series results in a copy of the original sequence. In a similar way, a series of structural effects is responsible for synthesizing strands of amino acids into proteins, this time, using an RNA molecule as the template and consuming energy from other molecules in the process. But the structural cause in this case is an enormously complex object with fifty-some different kinds of proteins and several strands of RNA (together with tRNA to supply the parts).

Enzymes bring out the appropriateness of thinking of the unchanging structures of molecules as machines. The free energy for the catalyst’s work comes from the potential energy of the forces by which the enzyme binds with the other molecules (the “substrate”), but that energy is not ultimately lost to randomness, because it is paid back from the free energy released in their forming stronger bonds as the other molecules are freed from the enzyme. Thus, the enzyme can act again. Enzymes can even construct complex molecules with weaker, energy-rich bonds by extracting free energy from energy-rich molecules available in the medium.

On a larger scale, what are called “physical properties” of bulk matter, from rigidity and elasticity to transparency, color and conductivity, are dispositions to behave in certain ways under certain circumstances. But they can all be explained as irreversible structural global regularities. The conditions under which the disposition is exhibited supply a form of free energy, and the way the material structures at the micro level within the composite object structures that thermodynamic processes explains why the physical object behaves as it does under those conditions.

The simplest case is rigidity itself, in which a force exerted on part of a composite object is communicated to other parts because of the bonds that are responsible for its unchanging geometrical structure.

This is the ontological explanation of the principle of the lever. The force exerted at the end of a lever on one side of the fulcrum moves the other end of the lever through a distance that depends on the geometrical structure, and thus, if the distance the other end must move is less, a weak force operating over a longer distance becomes a strong force operating over a shorter distance. It is simply how the material structure coincides with the free energy, in this case, the force being exerted on one end of the lever.

The collisions of billiard balls are an example of how rigidity itself is a structural cause. As the first ball hits the second and comes to a stop, the kinetic energy is absorbed, but since they are elastic, the energy is stored as potential energy in the forces among the parts of the billiard balls, and as those forces restore the shapes of the balls, their potential energy becomes kinetic energy again, making the second ball move away (conserving the total momentum of their interaction). The structural cause in the billiard balls is what is unchanging about the spatial relations of their parts as they absorb and release energy.

In malleable materials, by contrast, the structural causes lie wholly in the unchanging structures of the parts, because they are the only geometrical structures that do not change when the disposition is exhibited. Energy is absorbed locally from the forces imposed, because the molecules have shapes that allow them to switch their bonds with one another, giving the parts of the composite object new spatial relations to one another as parts of the whole. That is how the motion and interaction of the material structures add up in space, when they start out with such bonds to one another and free energy is supplied by a force being impressed.

Material objects also have other mass properties that can be explained in similar ways, such as transparency, electrical conductivity, heat conductivity. The colors that material objects appear to have when illuminated by the whole spectrum of visible photons comes from some wavelengths being absorbed, while others are reflected. The material structure responsible for this global regularity lies in various aspects of the micro-structure, which interact differently with different wavelengths of light. (But colors in this sense are, of course, physical properties, and they must be distinguished from the appearances of colors to the subject, which are qualia.)

The explanation of dispositions by material and structural ontological causation is a reduction of those regularities to spatiomaterialism, and since that demonstrates their (conditional) ontological necessity, it explains the nature of the casual connection involved in these efficient causes. In the case of dispositions, the regularities connecting causes and effects are just irreversible structural global regularities, whose ontological causes are like machines built into nature. The test conditions of the dispositions are the efficient causes, and what happens are the effects.

Reproductive global regularities.There is yet another kind of global regularity, because there is another kind of non-basic, or derivative, substance that can work together with space as an ontological cause to generate global regularities, namely, reproductive cycles. Such ontological causes derive from material and structural causation, but reproductive cycles work together with space to generate what are, by far, the most spectacular global regularities, namely, evolutionary change.

The ontological cause of reproductive global regularities is a derivative substance. It is constituted by a material structure that uses free energy to do work. But reproductive cycles are basically different from material structures, because their essential nature as a (derivative) substance has a temporal structure. Each reproductive cycle is, as the name suggests, a whole cycle of changes (exhibiting various irreversible structural global regularities), and thus, it takes place over a period of time.

There is an existential aspect to reproductive cycles, as there is to any substance, because they endure through time. But in the case of reproductive cycles, endurance through time does not come directly from matter enduring through time, but rather indirectly, because it also depends on how one cycle gives rise to another cycle as time passes.

Since each cycle in such a sequence takes time to be completed, the cycle itself does not exist fully at any moment. What does exist fully at each moment is the (complex) material structure that is going through the cycle (or what will be called the "primary structure"), and since it is the ontological cause of the irreversible structural global regularities that are the cycle of changes, the whole cycle is implicit in what exists at each moment as it is present.

Reproductive cycles have, in other words, more basic ontological causes. In addition to space (spatial causation), each series of cycles depends on a thermodynamic flow to supply the free energy (material causation) and a complex material structure that uses free energy to generate the cycle of changes (structural causation). Moreover, since reproductive cycles derive from more basic forms of ontological causation only with the addition of a temporal structure to their essential nature, that is, as a cycle of changes, time as well as space might also be said to be an ontological cause. But in any case, since a cycle of changes is what a complex material structure ( that is, the primary structure) generates, reproductive cycles themselves endure through time like substances.

Though their endurance through time makes it possible for reproductive cycles to work together with space as an ontological cause, they would not be able to generate a new kind of global regularity (that is, one that is basically different from the irreversible structural global regularities, or “structural effects,” generated ontologically by the complex material structure), if the complex material structure did not generate two basically different kinds of structural global regularities during each cycle, one that reproduces the complex material structure and the other that does non-reproductive work. The inclusion of reproduction along with other structural effects is what makes them reproductive cycles, rather than mere cycles, and as we shall see, having both kinds of structural effects is what makes reproduction the basic cause of natural selection and, thus, of evolutionary change..

Primary structures. The material structures going through reproductive cycles are ordinarily called "organisms" or "reproducing organisms," but since we will be recognizing a series of levels of part-whole complexity in organisms, I will use a technical term, "primary structure," to refer to the material structure that is responsible for the reproductive cycles being discussed.

Primary structures (including ordinary organisms) are complex material structures, because they are made up of many different parts each serving as a structural cause of a different structural global regularity during the reproductive cycle. But primary structures are a distinctive kind of complex material structure, because they are also the ontological cause of structural global regularity in which the entire, complex material structure is reproduced. That is, in addition to various forms of non-reproductive work, primary structures normally construct one or more new primary structures of the same kind to go through the next reproductive cycle alongside one another. In other words, in addition to surviving, organisms also reproduce.

The basic ontological effect of reproductive cycles and space is gradual change in the direction of greater power.

Because they reproduce, organisms tend to multiply in space as their reproductive cycles follow one another in time, and thus, since the organisms are all contained in the same region of space, their population growth causes a scarcity of free energy (if nothing else). Not all the organisms can continue going through reproductive cycles. But it is not just chance which ones continue, because they do non-reproductive work as well as reproduce. There is a natural selection that favors those organisms whose non-reproductive work promotes their reproduction, and thus, there is a change in the whole region in which organisms become increasingly powerful in controlling conditions that affect their reproduction.

Reproduction is, in other words, the basic cause of natural selection. Evolutionary change does not depend on changes in the environment. Insofar as natural selection is caused by reproduction, rather than environmental change, evolution is, as we shall see, a gradual change in the direction of an optimal state, or “natural perfection.” Gradual evolution is, therefore, progressive.

Besides “gradual evolution,” however, there is another global regularity caused by reproductive cycles, namely, “revolutionary evolution,” by which one stage of gradual evolution gives rise to another in a determinate series of evolutionary stages. The ontological cause of this aspect of reproductive global regularities is higher levels of part-whole complexity in the structures of the organisms going through reproductive cycles, that is, by higher levels of part-whole complexity in their primary structures.

Organisms are just complex material structures, or "primary structures," and thus, it is possible for organisms that have become nearly optimal by going through reproductive cycles to become bundled together as so many different structural causes that go through reproductive cycles as a whole, complex material structure, that is, on a higher level of part-whole complexity.

The advent of such a higher level of part-whole complexity in the structures of organisms is a revolutionary change, because it begins a new stage of gradual evolution, or change in the direction of natural perfection. The organisms that are evolving at the new stage start off simple, uniform and weak, and they gradually become increasingly complex, diverse and powerful. But since they have structures with a higher level of part-whole complexity, they are inherently more powerful in controlling relevant conditions than those at the previous stage, and their gradual evolution will make them far more powerful than the organisms that evolved at previous stages.

Since they are caused by higher levels of part-whole complexity in reproducing organisms, stages of evolution can occur only in a certain sequence, and thus, the overall course of evolution is an inevitable series of evolutionary stages. Since those stages are also change in the direction of increasing power, the overall course of evolution is progressive in a far grander way than the gradual evolution that occurs at each stage, for it proceeds by one revolutionary change after another in the direction of ever greater power to control relevant conditions.

(It should be noted at the outset that there are several sequences of stages of evolution in the overall course of evolution. The basic stages are caused by higher levels of part-whole complexity in primary structures, but there are other sequences of evolutionary stages, because new stages of evolution can also be caused by higher levels of part-whole complexity in secondary structures, or structures that are set up or maintained by the same kind of primary structure, including, as we shall see, levels of part-whole complexity in brain structure and levels of part-whole complexity in linguistic structures, such as arguments.)

Comparison to Darwinism.These reproductive global regularities, both gradual and revolutionary, are the ontological effect of reproductive cycles and how they add up in space as time passes. I will call it "evolution by reproductive causation." But it is basically the "mechanism" that Darwin discovered, the mechanism of random variation and natural selection. However, by deriving reproductive causation from spatiomaterialism (and the kind of space and matter required by the basic laws of physics), evolution is explained ontologically, as a global regularity. That will show not only that there are many aspects of evolution that are not currently recognized, but also that those aspects are inevitable in all spatiomaterial worlds like our own, that is, (conditionally) ontologically necessary.

At the outset, therefore, it may help put what is at issue in perspective to compare reproductive causation with Darwin’s “mechanism,” especially the current understanding of his mechanism. Evolutionary biologists tend to think of natural selection as an empirically discovered tendency, for that is how they defend their explanation of evolutionary change from creationists. But as we shall see, much more can be known about evolutionary change when it is explained ontologically.

Reproductive causation departs from contemporary Darwinism in two ways. On is its explanation of gradual evolution, and the other is its recognition of revolutionary evolution.

The basic cause of evolutionary change was discovered by Darwin as he thought about what happens in populations of organisms as they reproduce themselves. He saw that if variations on traits occur randomly in such organisms, and if those traits are inherited by their offspring, evolutionary change could occur simply as a result of the greater reproductive success of those organisms that have traits that are useful. This is what happens in breeding plants and animals, but he called it “natural selection,” because it occurs in nature without human intervention. Over time, the natural selection of random, heritable variations gives species traits that adapt them to their environments.

Such adaptations depend only on efficient causes, and thus, Darwin showed how evolution could happen in a materialist world, where everything is caused by how bits of matter move and interact with one another over time. It removed any need to appeal to a "designer" in explaining the wonderful functions found in the natural world. But there is considerable dispute about the status of Darwin’s “mechanism” and, thus, about the explanations of evolutionary change based on it.

Views range from thinking of Darwin’s mechanism as a principle or peculiar law of nature to thinking of it as a mere tautology (the survival of the fittest, where “fitness” is defined as surviving). Somewhere between them comes the belief that it is just a pattern for giving a kind of historical explanation of the evolution of traits, which is filled out by mentioning all the contingent details by which natural selection worked in any particular case. More recently, the computer analogy has led some to call it an algorithm (see Dennett 1995). And others take Darwin's mechanism to be a basic tenet that naturalists simply accept, helping to define “naturalism” (see Rosenberg 1996, p. 4).

However Darwin’s mechanism is characterized, contemporary Darwinists universally deny that there is any reason to believe that evolution is progressive. Most are wedded to an interpretation of Darwin’s mechanism that denies there is anything necessary about the overall course of evolution or about the species that evolve. It would all happen differently, if evolution were started over and allowed to play itself out again. I will call this prevailing commitment to the contingency of evolution accidentalism. The grounds for accidentalism come down to two main factors.

First, environmental change is what is thought to cause natural selection. If selection pressures are imposed on species by changes in the environment whose causes are external to evolution itself, the course of evolution cannot be predicted by Darwin’s mechanism alone, and in the words of Stephen Jay Gould (1976) , “Evolution by natural selection is no more than a tracking of . . . changing environments by differential preservation of organisms better designed to live in them”. (Gould, “Darwin’s Untimely Burial”, Natural History, Vol. 85, No, 8, 1976; reprinted in Ruse, 1989, p. 98.)liii

Elliot Sober (1984, p. 174) endorses this view of the effect of natural selection as “‘tracking’ the environment,” and he attributes it to Lewontin (1978) pp. 156-169. Even Richard Dawkins (1986, p. 179) agrees that evolution “constantly ‘tracks’ the changing environment.”

Second, when a change in a species’ environment occurs, there is no guarantee that the best adaptation will occur in response. Natural selection operates on random variations, and it has only whatever variations happen to be available at the time from which to select. There may be other variations which would be better, but since they are not tried out (or tried out only later, after another variation has already evolved), they cannot be selected.

As Michael Ruse (1986, p. 19), a leading philosopher of biology, puts it, “Given a need, the option taken to satisfy it is a function of what you have at hand, rather than what the perfect answer would be.”

According to E. Sober (1984, p. 174), evolution does the best it can with the random variations it has when the environment imposes a new selection pressure, but it is just a makeshift response to the exigency of the moment. See also Philip Kitcher, 1985, pp. 213-226. The most famous example of this contingency is, thanks to Gould (1980), the Panda’s thumb.

The upshot of accidentalism is that there is nothing necessary about the species that come to exist or the course of evolution. By seeing evolution as tracking environmental changes, accidentalists are taking the traits that accumulate in any species to be a record of the history of the environmental changes that happened to occur. After adapting to one environmental change, new traits are acquired that adapt the species to the next, and thus, the nature that a species now has depends on a series of selection pressures that could have been different.

Contemporary Darwinism makes it seem, in Kauffman’s (1993) words, that evolution merely “cobbles together jury-rigged contraptions” (p. 3). It sees “organisms as overwhelmingly contingent historical accidents, abetted by design” (p. 26). Or as Ruse (1986, p. 93) says, “you could as well have one organic state as another”.

As Mark Ridley (1985) explains, “Evolution is continually going on; the traits of lineages continually change. What will define a group at one time may not define it at another. The traits defining groups are temporarily contingent, not essential. Biological groups do not have Aristotelian ‘essences.’” (Reprinted as “Principles of Classification,” in Ruse, 1989, p. 178.)

E. Mayr, insisting that evolution is “opportunistic and unpredictable,” holds that “If evolutionists have learned anything from a detailed analysis of evolution, it is the lesson that the origin of taxa is largely a chance event.” He cites such factors as “the genetic composition of the founding population, the special internal structure of its genotype, and the physical as well as biotic environments that supplies the selection forces of the next species population.” (“Probability of Extraterrestrial, Intelligent Life,” reprinted in Ruse, 1989, p. 283.)

Richard Lewontin suggests that “[a]s far as we know all living organisms are connected by an unbroken chain of historical contingency,” in “The Shape of Optimality”, collected in Dupré (1987, p. 158).

Michael Ruse (1986, p. 20) says “there is nothing in selection itself which encourages progressionism” because “[w]hat counts is reproduction, here and now and in the immediate future. If the simpler, less intelligent form can do it better—and it often can—then so be it.”

The appearance that evolution is progressive has recently been given an accidentalist explanation by Gould (1996). He argues that there is an overall change in the direction of greater complexity, because starting with the simplest, that is the only direction that evolution can go.

What undercuts the traditional belief in “fixed species” is, therefore, the role of contingent factors in evolution, for they show that species will lack the necessity of natural kinds or essences.

Evolution by reproductive causation is not, however, accidentalist, but rather progressive. Nor does this progressivism abandon Darwin's mechanism.

It accepts the consensus among Darwinists about the three elements involved in the evolution of a population of reproducing organisms by Darwin’s mechanism. It agrees that there must be random variations in the traits of the organisms, that such traits must be heritable by their offspring, and that there must be a natural selection by greater reproductive success of members with certain traits.

But instead of assuming that that natural selection is due to externally caused changes in the environment, this ontological explanation of Darwin’s mechanism implies that natural selection is, in addition, due to the scarcity caused by reproduction itself. As organisms reproduce, their population increases, and the resources they need becomes scarce. Only some of them can succeed in reproducing. But it is not just chance which ones succeed, since different varieties have different powers to control conditions in the world. The survivors tend to be those that are more powerful in some relevant way.

Moreover, if the scarcity due to their own reproduction is a cause of natural selection, it must be the main cause, for there is one resource that is always eventually in short supply: free (or usable) energy. Thus, evolutionary change would occur, not just in response to changes in the environment, but continuously. As we shall see, such a steady cause has a continuous effect, and there is inevitably a gradual accumulation of traits in the direction of an optimal state, which I will call “natural perfection.”

This view of evolution will be called “reproductive causation,” because it takes reproductive cycles and how they add up in space over time to be the ontological cause of evolution. In other words, it takes the reproduction of organisms to be the ultimate cause of natural selection, for that is why their non-reproductive work is increasingly powerful.

Though this is different from the explanation of evolution given by contemporary Darwinists, it is worth noting that it may have been Darwin’s own view. In The Origin of Species, he introduced natural selection by appealing to Malthus’ theory of population growth—which holds that, while human population tends to increase by a geometrical progression, their resources increase by a mere arithmetical progression. Since it suggests that those who are best able to survive are the ones most likely to succeed in reproducing, Darwin called natural selection a “struggle for survival.” It was Spencer who called it the “survival of the fittest.”

Whatever it is called, the point is that reproduction itself is what puts members of a species at odds with one another. The cause of evolution is internal. Organisms need energy, and in any environment, reproduction will eventually cause a scarcity of usable energy, if nothing else, for it is a physical fact that the usable energy in any finite region of space is finite. Thus, even without externally caused changes, evolution would take place, whatever the environment. Thus, reproductive causation implies that accidentalism is false.

Reproduction is also the ultimate cause of stages of evolution, the other main departure from contemporary Darwinism. Stages of evolution are caused by the capacity of higher levels of part-whole complexity in the structures of the organisms to go though reproductive cycles as a whole, for once they occur as random variations, they impose natural selection of themselves and gradually become more powerful.

Contemporary Darwinists recognize what they call “punctuated equilibria” in the fossil record of evolution, but they have no general explanation of their cause. On the contrary, they are taken as evidence that Darwin’s mechanism is not the only cause of evolutionary change.

By tracing natural selection to its ontological causes, however, we can see why such revolutionary episodes in the course of evolution are inevitable. When higher levels of part-whole complexity that make organisms more powerful can occur as a random variation at all, they are inevitable, because they will eventually be tried out and, when they are, they will impose natural selection on themselves by their own reproduction, beginning a new stage of gradual evolution. Each stage is gradual change in the direction of increasing power for organisms of its kind, and thus, the series of stages is a step-like change in the direction of the increasing power of life itself.

By following out what is ontologically necessary about evolution in a spatiomaterial world like ours, therefore, we shall derive novel implications for almost every branch of natural and social science. And what is more, the progressivism of evolution provides an explanation of the nature of goodness.

These two reproductive global regularities are explained in greater detail in the following two sections.

The next section, gradual evolution, will explain the nature of the new (derivative) ontological cause (reproductive cycles) more completely than the foregoing sketch and use it to show the inevitability of a long term, gradual change in the direction of greater power. It will show that the outcome of such change is “natural perfection” for both organisms and the ecology of which they are part.

The following section, revolutionary evolution, deals with a consequence of recognizing reproductive cycles as an ontological cause, which is not even suspected by Darwinists. It will explain how space combines with reproductive cycles in a new way (by making possible higher levels of part-whole complexity in the structures of organisms) to cause more radical changes in evolution, each of which begins a new stage of gradual evolution. Thus, reproductive causation implies that evolutionary change involves an inevitable series of stages of evolution, and this section will describe in detail the essential natures of the organisms that evolve at each stage, which includes, by far, the bulk of the implications of ontological philosophy

Reproductive causation: Gradual evolution. The first of the two main kinds of reproductive global regularities is gradual evolution, and it will be explained here by considering, first, its Ontological cause, the existence of reproductive cycles in closed or isolated regions of space, and then, its Ontological effect, a global regularity in which evolutionary change leads gradually in the direction of an optimum, which will be called “natural perfection” because it makes the most of what is possible in a spatiomaterial world. In other words, reproductive causation implies that gradual evolution is progressive.

Though I have already suggested why gradual evolutionary change is ontologically necessary (in the introductory section of Reproductive global regularities), there is more to be said about its ontological cause. First, in order to show that reproductive cycles are an ontological cause, it is necessary to show how they derive from space, matter, and the ontological causes of simpler global regularities. Second, in order to explain what gradual evolution involves, it is necessary to explain what is meant by “natural perfection” and to show how this ontological cause generates gradual change in the direction of natural perfection in both the organisms and the ecology.

Ontological cause: reproductive cycles. What constitutes the ontological cause of gradual evolution is a way that all the simpler ontological causes of global regularities work together. Their combination yields a kind of (derivative) substance with an odd nature. It is the reproductive cycle. It is basically just an organism with heritable traits that normally reproduces itself during its lifetime. But explaining the derivative substances ontologically will show the necessity and character of the global regularities they cause.

Reproductive cycles are, in effect, “substances” that derive from material and structural causation. Enplaning that will show how reproductive cycles are reduced to spatiomaterialism, since we have already seen how those more elementary ontological causes are reduced to spatiomaterialism..

Material global regularities are involved, because what is going on in reproductive cycles is the use of free energy to do work, that is, to make things happen that would not otherwise happen. As we shall see, most of the relevant free energy is supplied in the way sketched earlier, that is, by the radiation from a star. That is a thermodynamic flow of matter toward evenly distributed heat, and when it is intercepted by a planet in orbit around the star, it can be used to fuel reproductive cycles. Cycles of reproduction are irreversible processes, though each reproductive cycle involves many structural global regularities.

Structural global regularities are involved because what uses the free energy to do work are structural causes. There are material structures that coincide with the thermodynamic flow of matter toward evenly distributed heat, and the ensuing motion and interaction results in certain specific effects, which are events that would not otherwise occur. This is an ontological explanation of how efficient causes produce their effects, as we have seen in the case of dispositions. In discussing structural global regularities, we saw that structural global regularities entail efficient-cause connections. What makes such structuring of the tendencies to kinetic energy and randomness into a new ontological cause is how structural causes are combined in the constitution of reproductive cycles.

Reproductive cycles. What makes the reproductive cycle a new ontological cause is the kind of material structure that generates this structural global regularity (which is ordinarily called an "organism"). It is a kind of material structure that generates a cycle of irreversible processes that includes both reproduction and non-reproductive work.

The organism. The organism is a complex material structure, for it includes a number of material structures bundled together as various structural causes. But in addition to the distinctive structural global regularity that each such a structural cause generates, there is a structural global regularity in which the material structure as a whole is reproduced, making the whole process generated a reproductive cycle.

Such material structures will be called "organisms," or "reproducing organisms, when they go through reproductive cycles on their own. But after a few stages of evolution, as we shall see, there may also be a few levels of part-whole complexity of such material structures within the reproducing organism, and so it will be useful to refer to material structures of this kind as "primary structures." That is, primary structures are complex material structures that are able to reproduce themselves, and the use of this technical term will make it easier to describe the structures of organisms at later stages of evolution.

Organisms (and primary structures) generate, therefore, two kinds of structural global regularities during a reproductive cycle. Each structural cause that is bundled together in the organism usually generates a different kind of structural global regularity. But the organism can also generate a structural global regularity as a whole in which it reproduces itself as a whole, including all the structural causes bundled together in it. In order to keep these two radically kinds of ontological effects of its structural causes straight, I will call the former “non-reproductive work” and the latter “reproductive work.”

I will call the structural global regularities generated by structural causes "structural effects" in order to have a simpler way of referring to them.

In organisms (and primary structures generally), many structural causes are bundled together, and since the structural global regularities that each generates involves a connection between an efficient cause and its effect, we can also say that different efficient-cause connections are bundled together in the organism. But that means that the structural cause is not just an ontological cause, but also an efficient cause, for its inclusion in the structure of the organism is sufficient to bring about the effect during the reproductive cycle. Such an effect is simply the difference that the structural cause makes to what tends to happen (in the organism, its behavior, or in the environment as a result of its behavior) because of the structural global regularity it generates. (Or as the technical formula for our ordinary notion of efficient cause goes, it is a non-redundant member of the set of conditions in the organism that is sufficient for the effect.) Such an effect is what I will mean by "structural effect."

Talk of “structural effects” ignores the difference between the material structure as the ontological cause of the structural global regularity and the inclusion of the material structure in the organism as an efficient cause (along with other conditions) of its occurrence during the reproductive cycle. But that is useful in describing organisms, because different parts of the organism are responsible for different structural global regularities and, thus, different structural effects.

The difference between the reproductive work and non-reproductive work of structural causes can, therefore, be put in these terms. Since the structural effect is the work done by the structural cause in generating a structural global regularity, the two radically different kinds work that are essential to organisms (and primary structures) can also be described as the organism's “reproductive structural effect” and its “non-reproductive structural effects.”

This will be useful, because in all organisms (and primary structures), including the most basic, it is not only the organism as a whole that has both a reproductive and non-reproductive structural effect. Each of the structural causes bundled together in the organism has both a reproductive and non-reproductive structural effect. In fact, the reproductive structural effects of the parts is what enables the organism to reproduce as a whole, for it is a process in which each part reproduces itself.

The non-reproductive structural effects of the material structures bundled together in an organism (or primary structure) are often called the "traits" of the organism. But notice that when traits are explained ontologically, their heritability by offspring is entailed. Since traits are non-reproductive structural effects of the material structures bundled together in organisms, they are necessarily inherited by offspring, because such parts of organisms (and primary structures) also have reproductive structural effects as part of the reproductive work by which the organism as a whole reproduces.

The cyclic structural global regularity. In order for reproductive cycles to exist, however, organisms must actually go through cycles in which they do both their reproductive and non-reproductive work. It is not enough for their material structures to endure though time without doing both kinds of work.

When structural causes are bundled together spatially as an organism, a number of different non-reproductive structural effects are bundled together. But these structural effects do not necessarily occur at the same time. The various structural causes often (though not always) have their non-reproductive structural effects at different times. But to hold that the organism goes through a cycle is to hold that its parts have structural effects that ultimately put the organism back in much the same position where it began, so that it can go through another cycle. That means that the bundle of structural effects has a temporal structure as a whole. Thus, not only are the structural causes bundled together in space as a complex physical organism, but their structural effects are combined in time as a cycle. It is a cycle of changes.

What makes the cycle a reproductive cycle, however, is that at some point during the cycle, the organism is reproduced. That is, one or more additional organisms of the same kind are constructed and put in a position to go through reproductive cycles side by side. The reproduction of the organism as a whole is essential to reproductive cycles being a new kind of derivative ontological cause.

In all the basic organisms, as we shall see, reproduction depends on each structural cause bundled together in them having a reproductive structural effect as well as a non-reproductive structural effect. (This is rather straightforward in the case of bacteria and protists, but it also holds in a more complicated way for multicellular organisms, as we shall see.)

Notice that crystals do not go through reproductive cycles of this kind. The reason crystals are sometimes said to go through reproductive cycles is that, as each molecule is added to the growing crystal, the structure required for the addition of another molecule is created, enabling the processes to be repeated. But this is not the kind of reproductive cycle that is an ontological cause of reproductive global regularities, because the crystal is not an organism (or primary structure) by our definition. It does not have a non-reproductive structural effect distinct from its reproductive effect, not to mention that with just one structural cause, it cannot be a bundle of structural causes at all.

Natural selection. Reproductive global regularities are caused ontologically by space and reproductive cycles (as a derivative ontological cause), because reproductive cycles add up in space over time to natural selection. That is, as they endure through time in the region, they reproduce, and since their own population increase makes free energy (or other resources) scarce, they impose natural selection on themselves.

Reproductive cycles endure through time like substances because they are cyclic. Each cycle begins a new cycle, and thus, the cycles have a continued existence.

Unlike basic substances, however, derivative substances can be destroyed. But since there is both a spatial and a temporal aspect to reproductive cycles, there are two ways that this kind of derivative substance can cease to exist. A cycle can go out of existence either because the material structure of the organism going through the reproductive cycle is destroyed, or because the organism is unable to generate its entire cycle of structural effects. But as long as they do not go out of existence, they are like substances, enduring through time.

As reproductive cycles, however, they also multiply in space. Endurance through time also involves, in the case of reproductive cycles, the reproduction of the organism going through them. That is, in addition to reproducing in time as one cycle follows another, they also reproduce in space as additional organisms of the same kind are constructed.

Reproductive cycles would not be a new kind of (derivative) ontological cause, if all they did was endure through time, for then they would be a mere cyclic irreversible structural global regularity, like a motor. The reproduction of the organism is what makes them a new derivative ontological cause.

Space is the other ontological cause of evolution, along with reproductive cycles.

Spatial causation is the only simpler kind of global regularity that has not been mentioned thus far in explaining the ontological cause of evolution. But spatial causation is one of the ontological causes of every global regularity, because the wholeness of space is what makes the motion and interaction of bits of matter in a region add up over time. And adding up in space to natural selection is just another such role for spatial causation.

In causing material and structural global regularities, however, the structure of space within the region was relevant in another way as well. Its geometrical structure was needed to explain why potential energy tends to become kinetic energy and why kinetic energy tends to become randomly distributed heat. And structural global regularities depend on the geometrical structure of space not only because it helps constitute material structures (that is, material objects with a geometrical structure), but also because it enables them to move around in space without changing their geometrical structures.

In the case of gradual evolution, by contrast, the geometrical structure of space within the region is not directly relevant. It is only the wholeness of space that works together with cycles of reproduction to constitute reproductive global regularities. Thus, the role of space as an ontological cause of evolution depends only on the fact that all the parts of space in the region fit together uniquely as a whole, much like how it worked together with matter to cause the conservation of matter.

Being contained by space makes reproductive cycles add up in a unique way as time passes. Since the continued existence of reproductive cycles entails the multiplication of reproductive cycles in space, expanding the population of organisms, it combines with the space that contains them to cause ontologically a scarcity that imposes natural selection on them.

Though the total matter in any isolated region of space does not change, there is a way that push comes to shove when some of the matter constitutes reproductive cycles. As the organisms going through them reproduce themselves, generation after generation, the reproductive cycles not only endure through time, but also multiply in space, and thus, the population of organisms grows. But the matter in the closed or isolated region must add up arithmetically in space as time passes, that is, as a total that does not change over time (according to the principle of the conservation of matter). Though some of the matter in the region must exist in the form of free energy in order for material structures to do work of any kind, there is only a finite thermodynamic flow of matter from potential energy through kinetic energy (and photons) to evenly distributed heat in any isolated region of space, such as a planetary system or the surface of a planet. Thus, as reproductive cycles multiply in space, scarcity of free energy, if nothing else, will eventually limit the number of reproductive cycles that can continue to exist in the region. Some reproductive cycles will have to come to an end.

In other words, organisms going through cycles of reproduction impose natural selection on themselves. That is how the wholeness of space works together with reproductive cycles to generate a new kind of global regularity. It is simply how reproductive cycles add up in space as time passes.

To be sure, it is natural selection, and not just random selection, because the organisms are not only reproducing, but also doing non-reproductive work which can control conditions that affect reproduction. Those differences among organism are, as we shall see, why natural selection leads to a gradual change in the direction of natural perfection. What makes such variations among organisms possible is that organisms have non-reproductive as well as reproductive structural effects. But what forces a selection to be made at all is their reproduction in space as well as time.

Random variations. This explains all but one of the three elements generally assumed to be part of Darwin’s mechanism. Since heritable variations and natural selection are entailed by the nature of reproductive cycles as an ontological cause, only random variations remain to be explained. There must also be random variation in the organisms in order for natural selection to cause evolutionary change. But random variations are due to another fact also implicit in the nature of reproductive cycles as a ontological cause.

What makes variations in the traits of organisms possible is the fact that organisms (and primary structures) are complex material structures, that is, that they are bundles of various kinds of structural causes. If different varieties of structural causes can be bundled together as a complex material structure at all, they can be bundled together in different ways. That is, different bundles can include different kinds of structural causes. New structural causes can be added, both new kinds and additional particular material structures. And the same structural causes can even be bundled together in different ways. The part-whole complexity inherent in structural causes being bundled together as organisms makes an enormous range of kinds of reproductive cycles possible.

The possibility of random variations is actualized in the simplest organisms, because the global regularity caused ontologically by their material structures is merely a tendency. The structural global regularity that they generate includes the construction of imperfect copies as well as perfect copies of their material structures, thereby introducing random variations.

Material structures have their ontological effects by how they channel the thermodynamic flow of matter toward evenly distributed heat. It depends on how the geometrical structures of the material objects involved coincide with the geometrical structures inherent in the thermodynamic flow of matter toward evenly distributed heat (the geometrical structure of potential energy being converted into the kinetic energy of objects and the geometrical structure of the nonrandom distribution of their causally relevant factors becoming random). Thus, when various material structures are involved (such as an organism and the many parts used to construct copies of it) or free energy is supplied to them in various ways (for example, by radioactive decay as well as chemical energy and the usual photons), what is ontologically necessary about the future may be only a tendency. In particular, the structural global regularities generated by simpler organisms include the construction of imperfect copies as well as perfect copies of their complex material structures. The imperfect copies will tend to resemble the structure of the organism being reproduced, but there will be random variations on it.

This is not to say that structural global regularities, as global regularities, are inherently probabilistic. With the addition of other material structures, it is possible to ensure that no errors occur in reproduction, as in some higher organisms. Reproduction is imperfect in simpler organisms because their material structures cannot control all the structural causes that may be relevant to what happens. The structural global regularity includes various different outcomes with different probabilities. In higher organisms, where reproduction is infallible, special mechanisms are required to introduce random variations.

Darwin’s mechanism as a consequence. Thus, the way that reproductive cycles add up over time in the wholeness of space includes all three of the elements generally considered essential to Darwin’s mechanism (natural selection, heritable traits, and random variations).

The bundles of structural causes that generate reproductive cycles as structural global regularities make up the populations of reproducing organisms in which Darwin’s mechanism is assumed to be at work.

Natural selection is caused by how reproductive cycles add up in space over time, that is, by the scarcity, due to population growth, that requires some reproductive cycles to come to an end.

Traits are inherited by offspring, because the traits are the non-reproductive structural effects of the structural causes bundled together as organisms and those same structures are what is copied in reproduction.

And there are random variations on the traits of organisms, because reproduction is a structural global regularity that involves only a tendency to make perfect copies (or there are mechanisms for introducing random variations).

All three elements of Darwin’s mechanism are entailed in the ontological cause of evolution as a reproductive global regularity.

It may seem paradoxical or even perverse to take reproductive cycles, rather than reproducing organisms, to be the ontological cause that helps constitute the reproductive global regularities. Organisms are three dimensional objects, which endure through time like other substances, whereas reproductive cycles are four dimensional objects, which endure through time only in the sense that the changes involved are cyclic and can go indefinitely. And since reproductive cycles are derivative substances, constituted by reproducing organisms (and a thermodynamic flow of matter toward evenly distributed heat), reproducing organisms do work together with space to cause ontologically the same reproductive global regularities.

There are two reasons for preferring to think of reproductive cycles as the ontological cause of evolution (along with space). The first is that reproductive global regularities are fundamentally different from simple structural global regularities, and the source of that difference is that reproduction occurs cycle after cycle (for it is the scarcity due to their population increase that imposes natural selection on them). And since an ontological cause is something that endures through time like a substance (or a basic relationship among substances), what causes evolution ontologically is the continued existence of reproductive cycles, not just the continued existence of reproducing organisms. What endure is a series of four dimensional objects with the property of multiplying in space.

The other reason has to do with the nature of the ontological effect. What changes in the entire region, as we shall see, is the kinds of reproductive cycles. Though these cycles are implicit in the organisms that are their ontological causes, the nature of changes that occur in evolution has to do with how they fit into the structure of the whole cycle, and we keep that in mind, by recognizing that the causally relevant unit is the whole cycle, rather than just the three dimensional organism.

Since reproductive causation entails all the essential elements of Darwin’s mechanism, it can explain everything currently explained in evolutionary biology. But this ontological derivation of them is not merely proof that there is an ontological necessity about what has already been discovered by empirical science. It is the beginning of a proof of new propositions about the course of evolution, first of all, that evolution is a gradual change in the direction of natural perfection.

Ontological effect: gradual change toward natural perfection. Reproductive causation implies that evolution is progressive. The reason for calling it progressive is that the global regularity constituted by reproductive cycles and space involves change in the direction of natural perfection. That is, as we shall see, how reproductive cycles add up in space over time. But this is also to introduce the foundation for explaining the nature of goodness, which is one of the mortgages that must be paid back in order to use spatiomaterialism as an ontological foundation, and thus, it is appropriate to start by explaining what I mean by “natural perfection” and making clear how it affords an explanation of the nature of goodness.

Natural perfection. A dictionary would tell us that “perfect” refers, in general, to the most complete, whole, or mature state of a thing, that is, a state without defects, a state in which no change would make it superior in any relevant way. Things can be perfect in different ways, but in every case, what makes the perfect stand out is that it is an optimal state that can hold in a certain kind of part-whole relation. And what I mean by “natural perfection” is a certain kind of optimal part-whole that is most appropriate to the basic nature of what exists in a world like ours, where everything is constituted by matter and space enduring through time.

What is perfect is always a whole that is made up of parts in some way. Though there are many different ways that parts can make up whole, the whole must be more than just the sum of its parts. There must be relations among the parts. And to be optimal, its parts must be of the right kinds and numbers and they must be related in the right ways. Thus, in general, a part-whole relation can be said to be optimal when it makes the most out of the least in some salient, determinate way. Though it depends on the kind of part-whole relation involved, perfection is an optimum that comes from combing the fewest and simplest parts of some kind so that the whole makes the most of them in a salient way.

Something can be said to be perfect of its kind, therefore, to the extent that it makes the most of things of its kind in the appropriate way. Beautiful works of art might be said to be perfect of their kind, because, given a suitable, classical definition of beauty, they involve such an optimal part-whole relation. But what I mean by “natural perfection” involves a far more basic part-whole relation, because perfection of its kind is a part-whole relation that makes the most of what exists in a natural world, that is, of the substances that endure through time.

In a spatiomaterial world like ours, perfection would have to make the most of space and matter enduring through time. Though its basic nature is just a form of matter in motion, it is not fair to paint the portrait of the world as a bleak picture of cosmic indifference. To living things, at least, there seems to be a difference between good an bad. And the significance of the law of entropy increase is not, despite its universality, that the fate of the world is a heat death in which everything has the same temperature. Rather, its significance is that there is such a thing as free energy, for that affords a salient way in which the most can be made of the parts in a spatiomaterial world like ours. Though entropy never decreases, the large scale structure of the universe is such that potential energy is constantly becoming evenly distributed heat, and since that means that there is a constant supply of free energy, there is a salient way that the most can be made out of what exists. As we have seen, material structures can use free energy to do work, and if such structural causes were to use as much of the free energy available in the region to do the work of controlling as much as possible what happens in the world, such a world would obviously have an optimal part-whole relation of the kind by which “perfection” is defined.

An optimal part-whole relation is one that makes the most out of the least, and in the case of something that is naturally perfect, the whole does the most in the sense of exercising maximum power, given the available free energy, and it does so with the least in the sense that it uses the fewest and simplest structural causes needed to exercise that power. That is an optimum that is often called “maximum efficiency,” though as we shall see, that does not characterize what is involved in natural perfection adequately.

Maximum efficiency is the kind of optimal part-whole relation that is the goal in designing machines. In the case of automobiles, for example, the goal is maximum power, reliability and efficiency in serving its function (say, safe transportation) at the least cost in parts, effort of construction and energy consumption. And since machines eventually wear out, the goal is a machine in which all the parts wear out at the same time.

Natural perfection involves maximum efficiency, but it is a more basic and, thus, more general kind of optimal part-whole relation, because it also involves doing as much as possible in the way of using free energy to control what happens in the world. The ultimate natural perfection is a optimum in which any relevant change in the parts or their relationships would make the whole less powerful.

Natural perfection is the direction of evolution by reproductive causation, but as we shall see, natural perfection involves several part-whole relations that are optimal in this sense. Two of them characterize the direction of gradual evolutionary change, the natural perfection of organisms and the ecology, as we shall see shortly. But gradual evolution is only one of the global regularities generated by reproductive causation, for there are also revolutionary episodes in evolution. Together, as we shall see, these two global regularities entail change in the direction of a natural perfection with an overall structure on planets (or in planetary systems) like ours.

Goodness. It should be noted at the outset that natural perfection plays a very important role in this ontological argument, because it affords an explanation of the nature of goodness, enabling us to pay back one of the four mortgages we took out in order to use spatiomaterialism as the foundation for proving these necessary truths in the first place (that is, along with an explanation of consciousness, how Einsteinian relativity could be true, and the existence of something worthy of worship).

Goodness can be defined in terms of natural perfection, because perfection is a kind of part-whole relation. Natural perfection is the property of the whole in such optimal part-whole relations, and so goodness can be defined as the property of the parts. That is, goodness can be explained ontologically as the property of contributing to the natural perfection of the whole of which it is part. And since all forms of natural perfection fit together in a necessary way as part of the overall structure of natural perfection, there are no ultimate conflicts about what is good, and goodness is simply the property of contributing to natural perfection.

Every part of the optimal part-whole relation that defines natural perfection is good, but since the perfect whole does the most with the least in the way of parts, each part makes a unique contribution. No part is redundant (though many parts of the same kind may be needed for the whole to be perfect).

By this definition of “good,” therefore, what is good ought to exist, because it is “called for” by natural perfection. That is, if anything that is good did not exist, the whole would not be naturally perfect. There would be a change that would make it more perfect. That is the sense in which natural perfection can be said to "call for" its existence.

Goodness is just a property of parts in relation to natural perfection, but as we shall see, it explains why all the things that are ordinarily considered to be good are good, including goals that are good for beings like us. It even explains an the aspect of goodness that makes such a theory seem impossible, namely, why rational beings ought to choose the good. And it reveals goals to be good that are not generally recognized as such today.

If evolution is progressive in the sense of involving change in the direction of natural perfection, it is also progressive in the sense of making things good (or bad). Progressive evolution is, in other words, the source of goodness in a spatiomaterial world, and since such evolutionary change is inevitable in a spatiomaterial world like ours, the ultimate source of goodness is the nature of the world itself.

The reason for believing that evolution by reproductive causation is progressive is that it is change in the direction of natural perfection, and in the end, there will be at least five different ways in which evolution by reproductive causation makes the world naturally perfect. They all fit together as part of a necessary overall structure, and since there are no basic conflicts to cast doubt on the whole being naturally perfect, it will be clear that the change involved in reproductive global regularities is indeed progressive. The first global regularity caused ontologically by space and reproductive cycles is gradual evolution, and it is change in the direction of the natural perfection of organisms and the natural perfection of the ecology. And gradual evolutionary change is itself a kind of natural perfection. Thus, three forms of natural perfection will be discussed below. Two further forms of natural perfection will be introduced later in this argument (both having to do with stages of evolution).

The natural perfection of organisms is maximum holistic power. The parts of this optimal part-whole relation are the structural causes that are bundled together as an organism going through reproductive cycles. Its power is holistic, because it depends on all the non-reproductive work done by its structural causes and all those parts must be of the right kinds and combined in the right ways. Its power is maximized in the sense that those non-reproductive structural effects control as many of the conditions affecting its reproduction as possible for organisms of its kind. But since free energy is consumed in generating structural effects, power is also maximized when the fewest and simplest structural causes are used because free energy is used most efficiently. Since that is to do the most with the least, maximum holistic power is a form of natural perfection, which will be called the “natural perfection of organisms.”

By the ecology, I mean how organisms exist alongside one another in regions of space. There must be an ecology, because organisms reproduce in space and go through reproductive cycles alongside one another. And there is a natural perfection about the ecology that complements the natural perfection of the organisms, because there is an optimal part-whole relation at the ecological level as well. It is also a kind of maximum holistic power. The parts, in this case, are the organisms going through reproductive cycles, and the whole is a power that depends on all the organisms in the region. Again, the whole is not merely the sum of the parts, because it depends on the kinds of organisms in the region, the numbers of each, and how they interact. In this case, however, holistic power is measured by how much of the free energy available in the region is being used by all of them to fuel their reproductive cycles. Given the kind of perfection that is appropriate in a spatiomaterial world like ours, that is the most salient way of doing the most that can be done. And as we shall see, it is also a case of doing the most with the least, because the organisms that use the free energy are each maximally efficient. I will call it the “natural perfection of the ecology.”

There is even a natural perfection about the process of gradual evolution itself, for there is a way in which evolution also makes the most out of the least when it is due to reproductive causation. In this case, the parts are all the moments in the course of evolution, and the whole is the overall course of evolution itself. Evolution by reproductive causation makes the most out of each moment, because the moments all add up as time passes to change in the direction of the natural perfection of organisms and their ecology. That is, since evolution is progressive, it is itself a form of natural perfection, which will be called the “natural perfection of evolutionary change.”

In order to show that evolution by reproductive causation is progressive, I will show that reproductive cycles add up in space as time passes to a gradual change in the direction of natural perfection. The first step is to see why organisms change gradually in the direction of maximum holistic power, and then why the ecology evolves gradually in the direction of their maximum consumption of the free energy available in the region.

Gradual evolution of the organism.The new derivative ontological cause that has been derived from spatiomaterialism is the reproductive cycle, and reproductive cycles add up in space as time passes by imposing natural selection on themselves. Reproduction is a cause of natural selection, because resources are finite and population growth eventually makes free energy (if not other resources) in any isolated region scarce. Though such scarcity is a change in the environment of each organism, it is not caused by anything external. It is internal, since reproduction is an aspect of reproductive cycles. And since population growth eventually leads to scarcity in a world like ours, some organisms will eventually be unable to survive and reproduce. But as long as there are new, heritable traits within the range of the traits being “tried out” by random variations that would make organisms better able to control the conditions affecting their reproduction, natural selection would tend to favor individuals with new traits that increase their power. Their greater reproductive success would eventually change the population until every member had the new trait (that is, acquired the new power).

If that is how reproductive cycles add up in space as time passes, we can see how evolutionary change would lead to the natural perfection of the organisms going through them. Reproduction would be the main cause of evolution, if these conditions held of organisms that start off simple, uniform and weak and it were possible for new traits to be tried out and bundled together with others in the organism, because evolutionary change of this sort would go on for a long time, adding one new trait after another, making the organisms complex, diverse and powerful. Indeed, it needn’t stop until the organisms are as powerful as possible for organisms of their kind, that is, until there are no more new power-enhancing traits within the range being tried out by random variations on existing organisms. That would be their maximum holistic power, because at that point, no change in the causal connections bundled together in their reproductive cycles that is possible for organisms of their kind would make them any more powerful.

This is to restrict the range of possible traits to those that can be "tried out" by random variations during their gradual evolution, and that depends on the nature of the organism and how random variations are generated (that is, the nature of the structural global regularity). It may be possible to imagine useful traits that fall outside that range, but that would not show that the organisms had a less than maximum holistic power in the relevant sense.

Example of amphibian evolution. To illustrate how reproductive causation could generate such a regularity, consider how it would explain fish evolving into amphibians. Reproduction among fish of various kinds would eventually cause a scarcity in the usable energy and other resources available in the water. Those fishes in which random variations happened to try out traits that enabled them to move their bodies across land, would find plants and other animals that provided a new source of usable energy. Those fish would tend to succeed in reproducing, while otherwise they might have failed.

Something like this apparently occurred among lungfishes about 345 million years ago. These fresh water fish had already evolved lungs, perhaps to absorb oxygen from the air when the water was stagnant and deficient in oxygen, and they had “lobe fins,” or large fleshy bases for their paired pectoral and pelvic fins, making it possible for them to move across land. At first, they were relatively uniform, simple and barely able to complete cycles of reproduction requiring locomotion across land. But reproductive causation would make them increasingly complex, diverse, and powerful. As random variations on their inherited multicellular structure tried out new traits, one new trait after another would be added. Each new trait would make them more powerful at controlling conditions that affected their reproduction, and as their complexity and power increased, new ways of controlling conditions could be tried out by random variations. Thus, fins would gradually evolve into legs, enabling them to crawl more efficiently across land, and since land plants and insects provided many different sources of usable energy, the different ways of acquiring energy would lead to the evolution of different species of amphibians. Amphibians would go on adding one new trait after another, increasing their power, until none of the new traits that could be tried out by random variations on their multicellular structures could make them better able to control conditions that affect their reproduction. Evolutionary change would stop only when they were as powerful as possible for organisms of their kind in whatever environment they occupied.

Such a proliferation of species is called a “radiation,” and it would occur again and again. When a more basic random variation on amphibians finally tried out internal fertilization (instead of fertilization in the water), making it possible for eggs that remained on land to house a form of embryological development that did not involve a larval stage, reptiles would be able to acquire usable energy from new sources on land. Two legged locomotion would be the start that gave dinosaurs their day in the sun. Those with wing-like limbs would begin a radiation of birds.

Long periods of gradual evolution are possible, however, only if the structure of the organism makes it possible for random variations to try out a wide range of new traits. In the animals mentioned above, what makes it possible to accumulate traits in that way is their multicellular structure. Each cell together with its behavior is at least one of the structural causes that is bundled together as parts of a multicellular animal going through a reproductive cycle, and what makes it possible to bundle such parts together is its way of coordinating their behavior as parts of an organism.

Random variations ultimately involve differences in genes, the most elementary structural cause with both essential kinds of structural effects in living objects. But as we shall see, genetic variations make it possible not only for cells to try out specializing in new functions, but also for multicellular organisms to try out new ways of arranging such cells. The latter aspect of random variations is possible because each multicellular animal is constructed by asexual division from a single, fertilized egg cell in a process called “embryological development.”

The kinds of random variations that can be tried out at any point determines the range of new causal connections that are possible at that point. And since they occur randomly, all but a few whose complexity borders on making them impossible would eventually be tried out in a finite period of time. Thus, random variations on existing multicellular structures are, in effect, continually “trying out” new, possible powers, as if they were feeling around for new conditions that it might be useful to control. Whenever a new trait happened to control a new relevant condition (or an old condition in better way), it would tend to be selected. Moreover, as multicellular organisms became more complex, new varieties would be added whenever some were able to tap a new source of energy or an old one in new ways, and each variety would become more powerful in its ecological niche.

The principle of gradual evolution. The example of the evolution of amphibians suggests a basic principle about gradual evolution. If evolution is by reproductive causation, then every power that it is possible for such organisms to evolve will evolve as it becomes possible. This may seem too progressive to be true, but consider the following.

(1) If organisms start out simple and uniform, all possible traits are likely to be tried out, because the range of random variations is not very large. And later on, when organisms are more complex and the range of possible random variations is greater, there will be many more varieties of organisms to try them all out.

This is to assume that a complex variety that acquires a new basic power which makes it better able to tap the usable energy claimed by another will tend to supplant the other. That may require violent storms or other disruptions.

(2) It is not necessary for a random variation to happen on the best way of controlling the relevant condition. Even a weak and unreliable way of controlling some new relevant condition would be selected, and as random variations on it were tried out, that structural cause would be shaped to control it as effectively as possible and to fit it together with other structural causes and their causal connections as harmoniously as possible.

(3) Nor is it plausible to suppose that there are possible powers that just happen not to be tried out, at least, not any basic ones, because organisms are not being forced to make do with whatever random variations are available at the time in order to adapt to externally caused changes in the environment. When the cause of natural selection is reproduction, they have all the time they need for random variations to “feel around” for new powers among alternative ways of controlling relevant conditions and make those traits maximally efficient.

Maximum holistic power. Natural perfection in organisms is maximum holistic power, or the maximum power of the organism to control all the relevant conditions using the fewest and simplest non-reproductive structural effects. That is the optimal part-whole relation in organisms. Let me explain these terms.

Power. What is maximized is power. Power is the capacity of structural causes using free energy to make things happen that would not otherwise happen. The power that is maximized in organisms is the power of its structural causes to do non-reproductive work.

Holistic. The relevant power is holistic, because it is the result of many structural causes working together in some way over the period of the reproductive cycle. Organisms are bundles of structural causes that are reproduced as a whole during the cycle, and each structural cause is responsible for a non-reproductive structural effect, or what is usually called a “trait.” Each such structural cause is a part of the organism that generates a structural global regularity in which free energy is used to make something happen in the world that would not otherwise normally happen, and with many different structural causes bundled together in the organism, their structural effects may occur at any time during the reproductive cycle (including some that occur during the whole cycle, such as the circulation of blood in multicellular animals). Thus, the relevant power of the organism is holistic, because it includes all the non-reproductive work its structural causes do during its whole reproductive cycle.

Relevant. The structural effects that are relevant to the maximum holistic power of the organism are those that control conditions that affect its reproduction. Though it is possible for structural causes to control many kinds of conditions in the world, not all such powers are relevant to the optimal part-whole relation in organisms. Powers are not relevant if they make no difference to whether or not the organism reproduces. In order to contribute to the maximum holistic power of the organism, structural causes must control some relevant condition. (However, this limitation on the powers that are relevant changes, as we shall see, with the evolution of rational animals.)

Maximum. Holistic power is maximum when the organism’s non-reproductive structural effects control as many of the conditions affecting its reproduction that it is possible for it to control.

The powers that are possible are those that are within the range of those tried out by random variations on evolving organisms as they are evolving, including both variations in kinds of structural causes and variations in how they are arranged in the organism (perhaps at several levels of part-whole complexity).

The whole is not just the sum of its parts, because the structural causes depend on one another in various ways to control relevant conditions. The whole is both spatial and temporal, because the structural causes are different parts of the complex material structure that goes through the reproductive cycle (that is, the organism), and they have their structural effects at various times during the cycle. For the power of the whole to be maximum, therefore, the structural causes must be of the right kinds and numbers and they must combined in the right ways. That means that all the relevant conditions must be controlled with the fewest and simplest structural effects, for there is a cost in generating any irreversible structural effect.

When holistic power is maximum, the organism does the most with the least. It is not just the greatest combined power to control relevant conditions, but such a maximum using the fewest and simplest structural causes. Such an optimal part-whole relation is like maximum efficiency, the goal in designing machines. But I will call it “maximum holistic power,” rather than maximum efficiency, because I do not want to suggest that there is some overall function that organisms are serving. The optimum for organisms involves controlling all relevant conditions that can be controlled by organisms of its kind, that is, maximum holistic power to control relevant conditions.

In sum, the natural perfection toward which the gradual evolution of organisms proceeds is their maximum holistic power to control relevant conditions.

Every relevant power evolves as it becomes possible. The powers are the effects of structural causes that are bundled together as the organism going through the reproductive cycle, which are usually identified as traits serving some function. Each kind of structural cause is shaped to make its effect as powerful as possible in controlling some relevant condition. Structural causes are added to the organisms, both new kinds or more of old kinds, as long as they control some new condition affecting reproduction or some old condition more effectively. And the structural causes are shaped so the their effects fit in with the other traits as harmoniously as possible.

Thus, assuming that organisms start out simple, uniform and barely able to complete cycles of reproduction at all, they become more complex, diverse, and powerful. Eventually, all the structural causes that could help control conditions that affect the reproduction of organisms tapping some source of energy will be bundled together harmoniously in a reproductive cycle. Such gradual evolutionary change must stop only when there are no changes within the range of possible random variations that can make them more powerful in controlling relevant conditions. Though this end may be approached asymptotically, evolution will be in the direction of bundles of structural causes whose power, taken together over the whole cycle, is maximum.

Functional explanation. Since the gradual evolution of organisms is in the direction of natural perfection, there is an ontological definition of “functional,” one that entails the validity of functional explanations. This implication of spatiomaterialism solves various philosophical problems about the nature of functions, which are discussed in Epistemological philosophy of causation. But functions must be mentioned here, because I will talk about them and use them to explain what evolves. And though traits of organisms are only one sort of thing that is functional, if evolution is due to reproductive causation, I will discuss how they are functional here, since they are the focus of attention in contemporary biology.

In other words, there are "ends" built into nature, much as the teleological view of nature has long supposed. But change does not occur for the sake of such ends because of final causation, as Aristotle believed. Instead, such changes are inevitable products of evolution. They are consequences of the reproductive cycle as an ontological cause of global regularities.

Functions as descriptions of traits. The functions of traits are the relevant conditions that they control. What is bundled together as an organism going through reproductive cycles are structural causes, and as organisms change gradually in the direction of natural perfection (for organisms of their kind), structural causes come to control conditions that affect their reproduction. Those relevant conditions are the functions served by the traits of the organism.

The function of a non-reproductive structural effect is to control some condition that affects the reproduction of the organism of which it is part, and being functional in that way is what it contributes to the natural perfection of the organism.

Thus, any of the objects, events or conditions that are involved in the structural cause bringing about its non-reproductive structural effect can be said to be functional and to have the function of controlling the relevant condition involved, including all the features of organisms that are identified as its traits. Thus, not only the heart, but also the beating of the heart, is functional, because it is part of the structural effect by which energy is distributed to all parts of the animal body.

To be functional is to be good. Since being functional entails controlling a relevant conditions, it contributes to the natural perfection of the organism, and that is the definition of “good.” Functionality is a form of goodness.

Functions as explanations of traits. Functions are not, however, merely a way of classifying traits by the relevant condition they control, for they are also causes of traits and can be used to explain them. The relevant conditions that must be controlled in order for the organism to be naturally perfect are in the cards, so to speak, because, as we have seen, every possible power inevitably becomes actual as it becomes possible. What it is possible to control depends on the range of structural causes that are tried out as random variations on the evolving organisms, and since those structural causes among them that promote the reproduction of the organism will eventually be naturally selected, the organism will inevitably acquire all possible structural causes that control some relevant condition. Thus, the organism acquires them because they are functional, and the function can be said to be the cause of the evolution of the trait that serves them. The function explains, therefore, the existence of the trait in the organism.

This causal connection seems puzzling, because the traits are also the efficient causes of the conditions they control, which are said to be their functions. The heart causes the circulation of the blood that is said to be its function. But there is a reverse causal connection in which the functions cause their traits. The function of circulating the blood is what causes the heart to evolve. What makes this true is that the former is a case of structural causes generating a structural global regularity, whereas the latter is a case of reproductive causation generating a reproductive global regularity, namely, the global regularity in which all possible powers necessarily become actual.

Since functionality is a form of goodness, it follows that the goodness of the trait can also be said to be what causes it to evolve. Among the possible traits, those that are good are naturally selected because they contribute to the maximum holistic power and, thus, the natural perfection of the organism.

“Survival and reproduction.” Finally, if evolution is by reproductive causation, it is misleading to say that traits "contribute to the organism’s survival and reproduction.” Though it may not be false to say that traits are selected for contributing to the organism’s survival and reproduction, that phrase makes it sound as though traits, and even survival, are merely means to the end of reproduction. But almost the opposite is true, if evolution is a global regularity caused ontologically by the reproductive cycle.

The end for which the traits are means is not reproduction, but controlling relevant conditions. The organism has the traits because they contribute to maximum holistic power in controlling conditions that affect its reproduction. The fact that natural selection is made by success in reproduction means that what is selected is the whole bundle of causal connections, rather than some particular trait. And as we have seen, since natural selection is also caused by reproduction, the bundle is selected for its power to control all the conditions that affect its reproduction over a whole reproductive cycle. Any particular trait is included only because it controls some relevant condition that would not otherwise be controlled.

Non-reproductive structural effects have functions, as we have seen, because they control relevant conditions. The relevant condition they control is their function. Though reproduction is also a structural effect, it has no function. Reproduction is merely the cause of evolutionary change in the direction of natural perfection, including the maximum holistic power of organisms. Thus, reproduction determines which conditions it is relevant to control. But that does not make reproduction the ultimate function of non-reproductive work. Evolution is not change in the direction of reproduction, but in the direction of the maximum holistic power of organisms, or their natural perfection.

In other words, what is good for the organism is not reproduction, but controlling conditions that affect reproduction (though the latter may include some that are more closely related to reproduction, such as a mating or caring from offspring in the case of animals). When the organism controls the relevant conditions, reproduction generally takes care of itself, since it has been part of the reproductive cycle from the beginning.

Gradual evolution of the ecology.Implicit in the gradual evolution of organisms is the gradual evolution of their combination in regions of space, or the ecology. If organisms start off simple, uniform and barely able to complete reproductive cycles, then reproductive causation will make them not only more complex and powerful, but also more diverse. The usable energy in any region of space is not only finite, but takes many different physical forms, such as various kinds of photons, energy-rich molecules, and other organisms. Thus, as these organisms specialize in tapping different sources of energy (or the same sources of energy in different ways), they radiate into all possible ecological niches, and evolutionary change in them—and in whatever other organisms may remain and adapt to them—will be in the direction of their maximum consumption of free energy, which is the natural perfection of the ecology.

At the ecological level, there is a part-whole relation which can be optimal in the way that is appropriate in a spatiomaterial world like ours. The parts are the organisms, or bundles of structural causes going through reproductive cycles, and the whole is not only how the organisms are combined spatially in the region, but also how their reproductive cycles are combined in time over a period that is long enough to include all and any regular changes in the environment, such as seasons. The species of organisms that evolve during any radiation tend to mirror the sources of usable energy in the region. As each species becomes more efficient and approaches the maximum holistic power for organisms of its kind, reproductive causation is also making their combination in the region optimal, but in a different way from the organisms.

The effect of the whole combination of organisms that is being maximized is the consumption of free (or usable) energy to fuel cycles of reproduction. Any unused free energy is an ecological niche to be occupied, if traits being tried out by random variations on any existing organism enable it to tap the energy as fuel for its reproductive cycles, for that overcomes the scarcity due to population growth. Thus, all possible ways of tapping usable energy come to be included in the ecology. And organisms are combined in the most efficient quantities, since the finite amount of usable energy is what stops population growth and causes natural selection in each species. The maximum may be approached only asymptotically, but as reproductive causation maximizes the power of the organisms over their whole reproductive cycle, evolutionary change at the ecological level is in the direction of appropriating more and more the usable energy in the region to fuel reproductive cycles, making the ecology as a whole maximally powerful in the way that is appropriate to a spatiomaterial world like ours.

Evolution by reproductive causation is change in the direction of natural perfection for both the individual organisms and their ecology. Indeed, it is only because the organisms have maximum holistic power that the ecology does the most with the least.

Natural perfection at the level of the ecology is using as much of the available free energy as possible to fuel the reproductive cycles of maximally efficient organisms of many varieties. But it does so by combining the simplest and fewest organisms—simplest because maximum holistic power at the level of individual organisms is using as little usable energy as possible to exert the greatest power to control all the conditions that affect its reproduction, and fewest because there are no more organisms than the supply of usable energy will support. Thus, these two forms of natural perfection are opposite sides of the same optimum: using the most energy to maximum effect. In other words, gradual evolution is change in the direction of a “compound” natural perfection, because the optimum for the ecology is a whole made up of parts that are, themselves, optimal as organisms.

This kind of perfection is rightly called "natural," because it makes the most of the basic nature of what exists in a spatiomaterial world like ours. The only possible way of making the most of space and matter in time is using free energy to control what happens in the world. At the end of gradual evolution, not only does the ecology consume as much of the free energy available to control conditions in the world as possible, but also all the conditions in the world that can be controlled by them are controlled (because the organisms are as powerful as possible for organisms of their kind and they use as little free energy as required for that maximum).

The natural perfection of the ecology has the same implications for organisms that its member the natural perfection of the organism has for its traits. Just as the organism's traits are functional because they control some relevant condition, so organisms in the ecology are functional because they consume some of the available free energy. And since to be functional is to be good, organisms are also good because they consume the free energy in some form or way. That is what the organism is good for, as far as the natural perfection of ecology is concerned.

The analogy among kinds of natural perfection suggest a further step. There is, as I suggested earlier, another kind of natural perfection about gradual evolution, namely, the way in which reproductive causation brings about the natural perfection of the organism and the ecology. Each phase of the process of gradual change in that direction makes a necessary contribution to their existence at the end, and since that is also an optimal part-whole relation, each phase can also be said to have such a function and to be good for contributing to the perfection of the whole in that way.

Finally, if natural selection is caused by reproduction, change in the direction of this compound natural perfection is inevitable, for it does not depend on externally caused changes in the environment. To be sure, evolutionary change itself may be seen as a change in the environment. As organisms become more powerful, traits that random variations have been trying out all along but were neutral or even harmful may suddenly become useful in promoting reproduction because of how they work together with other traits that have been acquired in the meantime. Or traits that first evolved to control one condition may come to control others. And evolutionary change in one species may change the effects of the traits of other species, requiring them to adapt or become extinct. But if such changes in the effects of traits are environmental changes, they are not caused externally. They come from the increasing power of the evolving organisms in whatever environment they all inhabit and, thus, are internal to evolution by reproductive causation, like scarcity due to population growth.

Reproductive causation: Revolutionary evolution. There is another reproductive global regularity, because there is a further way in which reproductive cycles can work together with the space containing them to generate another global regularity. It can occur only when reproductive cycles have already been gradually changing for some time in the direction of natural perfection, but it takes evolution beyond that the limit of optimum. The ontological cause comes from a more radical variation in the organisms that have already evolved, namely, higher levels of part-whole complexity in the structures of the organisms going through reproductive cycles. Since such a random variation begins a new stage of gradual evolution, which can in turn make possible yet another such revolutionary change, it generates is a series of stages of gradual evolution, and thus, this global regularity is “revolutionary evolution.”

It is evident that something more is needed to explain evolution on earth. Though the radiation of increasingly powerful organisms into all possible ecological niches can explain some of the variety among organisms, the basic reproductive global regularity implies that evolution is just one long, incremental change. Though gradualism is what Darwin expected, Darwinists now believe that the organisms found on earth are far too various, if not also too complex, to be explained by a gradual change in the direction of ever greater fitness.

Indeed, there is good evidence against gradual evolution. The fossil record reveals that, time and again, after a long period of little change, new species show up quickly, usually many species at about the same time, only to be followed by another long period of very little change. Called “punctuated equilibrium,” this phenomenon cannot always be explained as a radiation in which organisms of some kind acquire the power to tap a new source of usable energy in the environment. Something besides the addition of one new trait after another is helping determine the overall course of evolution.

Reproductive causation offers, however, a simple and plausible explanation of these phenomena. The further way that space can be combined with reproductive cycles to constitute a global regularity entails stages of gradual evolution. Such stages can explain not only why evolutionary equilibria are punctuated by the appearance of many new species all at once, but also why organisms are so much more varied than would be expected of gradual evolution. Furthermore, the sequence of stages makes evolution change in the direction of a natural perfection that is far grander sense than merely maximizing the holistic power of both organisms and ecology. Let us consider, first, the ontological cause of revolutionary evolution, and then the ontological effect itself.

Ontological cause: levels of part-whole complexity. Though the basic ontological cause is reproductive cycles, they can help generate another reproductive global regularity, because reproductive cycles can combine with space to cause ontologically a new stage of gradual evolution.

What goes through cycles of reproduction are the many structural causes bundled together as the complex material structures that I have been calling “organisms.” That part-whole complexity about each organism is what makes it possible for a gradual evolution to go on for a long period, because that is the source of the wide range of random variations that can be tried out and that can accumulate as the many new traits that make organisms increasingly complex, diverse, and powerful. But that same aspect of the nature of organisms suggests another possibility. Once organisms have approached natural perfection for organisms of their kind, it may be possible for those organisms to serve as various structural causes that are bundled together in a new organism, so that they all go through reproductive cycles as a whole. That is what I will call a “higher level of part-whole complexity” in organisms.

Organisms are complex mechanisms that can fairly be said to behave in various ways, because they are bundles of structural causes whose effects work together to control all possible conditions that affect their reproduction. Such parts are responsible for the non-reproductive structural effects that are called “traits,” but their functions, or the relevant conditions they control, may lie either in the organism (determining its physical properties and how they change) or in the world in which the organism exists (such as acquiring energy from the world and sending offspring into it).

The simplest way that a higher level of part-whole complexity is possible is for such organisms to be bundled together as a complex material structure that goes through reproductive cycles as a whole. Each simpler organism that is included would then be a structural cause with effects that are (or become) functional traits of the higher level organism.

(In this case, it is a higher level of part-whole complexity of primary structures. A "primary structure" is a material structure that can generate an entire reproductive cycle, including both reproductive and non-reproductive work, and since the lower level organism is a primary structure, a higher level of part-whole complexity based on such organisms is a higher level of part-whole complexity in primary structures. I use this simple case to introduce the cause of evolutionary stages, though as we shall see, there are other ways in which higher levels of part-whole complexity can cause additional stages of evolution.)

But in order to go through reproductive cycles as a higher level organism, the structural causes combined in its material structure must work together in the cycle to control conditions that affect its reproduction, and what is more, all the parts must be reproduced in order for the higher level organism to be reproduce. Thus, it is also necessary to coordinate their behavior.

A behavior guidance system is, therefore, required for organisms to be combined as parts of a higher-level organism (that is, an organism with a higher level of part-whole complexity in primary structures). Some such system must be part of the random variation that gives rise to the higher level organism.

I will call it a “biological behavior guidance system.” (This is to distinguish it from another kind of behavior guidance system that will also turn up as part of this global regularity, namely, the animal behavior guidance system, whose function is to guide the behavior of whole organisms in acting on other objects in space.) The function of the biological behavior guidance system is to coordinate the behavior of the lower level organisms (or primary structures) of which it is composed so that it can go through reproductive cycles as a whole. And its physical nature depends on the nature of the organisms (or primary structures) whose behavior is being coordinated.

By coordinating the lower level organisms (or primary structures), the biological behavior guidance system will have structural effects that can control conditions that affect reproduction. But in order to go through reproductive cycles, it must also be able to reproduce the higher level organism as a whole. But this is possible, because its parts are organisms that evolved during the previous stage and (as primary structures), they are already able to reproduce themselves. The reproduction of the higher level organism is simply a matter of coordinating its parts to reproduce as part of the same process. But the capacity to control the reproduction of its parts can also be used by the higher level organism to do non-reproductive work.)

In general, it is already possible to see how a higher level of part-whole complexity would cause a new stage of evolution. Assuming that it is possible for reproductive cycles with such higher level organisms to be tried out as a random variation on organisms that have already evolved, they would have the power of a whole army of the structures of lower level organisms to control conditions that affect its reproduction as a whole. This quantum leap in power would enable them to begin a new stage of evolution.

Since they would come to exist at first from a radical random variation, the higher level organisms would start off simple, uniform and weak. But assuming that they go through reproductive cycles, reproductive causation would shape them to control conditions affecting reproduction that were simply beyond the reach of lower level organisms acting separately. That is, as random variations in the kinds, numbers, and arrangement of the lower level organisms (including how their behavior is coordinated) were tried out, the scarcity due to their own population growth would impose a natural selection on them, and the higher level organism would become more complex, diverse and powerful. There would be enough new powers to be acquired for an entire stage of gradual evolution, because the potentially functional traits of a higher level organism are caused by the kinds, numbers and arrangements of its lower level parts. Thus, organisms would change gradually in the direction of natural perfection for organisms of their kind.

As they approach natural perfection for organisms of their kind, however, another such radical random variation may be possible. Its yet higher level of part-whole complexity would begin another stage of gradual evolution. Thus, as one stage followed another, evolution would be an overall change in the direction of what might be called the “natural perfection of life,” in which increased power comes from higher levels of part-whole complexity.

The spatial derivation of the ontological cause. Higher levels of part-whole complexity in the structures of the organisms going through reproductive cycles are, therefore, the ontological cause of the revolutionary episodes in evolution that being new stages of evolution. Though, as we shall see, such stages of evolution follow one another in such a way that evolution is change in the direction of a grander form of natural perfection, higher levels of part-whole complexity are just a complication of the ontological cause that is already at work in causing gradual change in the direction of natural perfection, the basic reproductive global regularity. Evolutionary change is still just how the wholeness of space makes reproductive cycles add up as time passes. But in causing revolutionary change, space works together with reproductive cycles in a further way, because the structure of space within the region is what makes it possible for the structures of organisms from one evolutionary stage to be bundled together as the various structural causes making up a higher level organism.

The relevant part-whole relation is a kind of spatial relation, and it is because the structures of the the lower level organisms coincide with space that it is possible for them to be combined as the several parts of a higher level organism. This role of space as an ontological cause resembles the role it played in causing structural global regularities, for the structure of space is what made it possible for simpler material objects to be combined as composite objects with geometrical structures and for such material structures to move around in space. And the new (derivative) ontological cause also comes from a new kind of unity, the way in which the structures of lower level organisms are combined as parts of a single higher level structure (just as material structures came from a new kind of unity of material substances that gave them an unchanging geometrical structure as a whole).

Though the part-whole relation in space is also what makes higher level organisms possible, organisms are not just material objects. They must reproduce as well as do various kinds of non-reproductive work in order to go through reproductive cycles. Thus, combining simpler organisms as parts of a higher level organism cannot usually be accomplished by simply attaching them to one another. They need a biological behavior guidance system to coordinate the behavior of their parts.

What makes reproductive cycles a different kind of ontological cause from the complex material structures that go through them is their temporal structure. That is, the new kind of unity behind the ontological cause of reproductive global regularities is the temporal unity of the cycle of reproduction. The way that time is part of the nature of the ontological cause is what makes reproductive global regularities so dramatically different from structural global regularities.

It is, however, space that makes revolutionary evolution so different from gradual evolution. Space together with the structures of lower level organisms constitute the higher level organism, and since space has a structure that allows higher level organisms to go through reproductive cycles, the wholeness of space plays its familiar role, making reproductive cycles add up over time so that the scarcity caused by their multiplication imposes natural selection them and organisms evolve gradually toward natural perfection for organisms of their kind (and help make the ecology naturally perfect in the process).

Since wholes in part-whole relations can be parts of more inclusive wholes, there can be a series of part-whole relations in the structures of material objects. Keeping track of them is what will enable us to trace the stages of gradual evolution that occur in its overall course. Since the notion of “a series of levels of part-whole complexity” is so central to this argument, it is worth the risk of belaboring the point to be clear about what is meant by it.

To illustrate what I mean, consider a box containing many similar cartons each filled with objects of some kind. Both the box and the cartons are wholes made up of parts, but the parts in the box are themselves wholes, namely, cartons, each containing many parts of some kind. It is even clearer how levels of part-whole complexity can form a series, each nested inside the next, when there are more than two levels of part-whole relations. Each of the cartons contained in the box may contain objects that are themselves containers of many similar objects (such as packs of cigarettes). Or going in the direction of the larger, the boxes of cartons of packs of cigarettes may be loaded together in a semi-truck’s shipping container which, in turn, is contained within a ship’s hull. There is, in principle, no limit to the number of levels of part-whole relations in a series. (In the decimal representations of numbers, for example, each decimal place represents a whole that is made up of ten “parts” in the decimal place to its right, and there is no limit to the number of decimal places in numbers.)

However, the “wholes” that are relevant to reproducing organisms are not just spatial structures made up of spatial parts, but rather spatiotemporal wholes made up of parts generating structural effects, that is, cycles of structural effects. Thus, a better, though still rough, model for a series of levels of part-whole complexity would be the levels of government into which individuals are organized in the United States: local, state and federal. Taking individuals to be the parts in which the simplest structural effects, local government can be seen as wholes that are then parts of state governments, which are wholes that are, in turn, parts of the federal government. There are three levels at which structural effects are bundled together as wholes that are, in turn, bundled together as (complex) structural effects on a higher level of government.

Kinds of levels of part-whole complexity. When a series of levels of part-whole complexity is found in a single organism, there is a determinate order to the material structures involved. And since reproductive causation works from simpler to more complex organisms, the stages of evolution by which the levels of organization accumulate have a determinate temporal order. But the actual series of levels of part-whole complexity that determines the overall course of evolution are of two or three different kinds, and each kind of part-whole complexity involves a different series of levels.

The basic and most obvious series is the series of “levels of biological organization.” They are the kind of part-whole complexity that has been mentioned thus far in describing the ontological cause of revolutionary evolution, in which lower level organisms are bundled together as parts of a higher level organism to go through reproductive cycles as a whole. (Since the material structures of independent organisms are primary structures, which can generate all the structural effects required to complete an entire reproductive cycle, including both reproductive and non-reproductive work, these are levels of part-whole complexity in primary structures.)

Multicellular organisms are the best example of them. Indeed, they are named after the level of part-whole complexity that is obvious in them (being composed of many cells). But it is only one in a series of levels of biological organization.

It should not be surprising that there is at least one more level of part-whole complexity in primary structures in the direction of the small from multicellular organisms, because each of the cells is itself a whole composed of parts that are also primary structures. The behavior of each cell is known to be determined somehow by many genes, and genes do both reproductive and non-reproductive work There is however, as we shall see, an additional level of part-whole complexity between cells and genes (and genes themselves have the part-whole structure required to be complex material structures of the kind required for reproductive causation).

Moreover, there is a level of biological organization above multicellular organisms, for example in insect colonies and, in a unique way as we shall see, in human society, yielding five distinct levels of part-whole complexity in primary structures altogether.

Within the structure of multicellular animals, however, there is another series of levels of part-whole complexity. It occurs in the nervous system. “Levels of neurological organization,” as I will call them, are capable of causing stages of evolution, because the nervous system is the system for guiding the behavior of multicellular animals, that is, its “animal behavior guidance system.”

The nervous system is composed mainly of neurons, and since neurons are cells, they can also be organized at a series of level of neurological organization. Not only individual neurons, but whole systems of neurons can be multiplied in number and fit together as parts of a super-system of neurons at the next level. But they are not levels of part-whole complexity in primary structures, because systems of neurons are not able to reproduce on their own. They are levels of part-whole complexity in a structure set up by the animal's primary structure.

Since each higher level of neurological organization can open up an entire range of powers that were previously out of reach, the evolution of a higher level can begin a whole new stage of evolution. Then, as it approaches natural perfection for organisms with its level of neurological organization, yet another level can be tried out, and thus, the series of neurological levels can cause a series of stages in the evolution of multicellular animals.

Let me emphasize that, since the nervous system is an organ set up by the biological behavior guidance system of multicellular animals, the stages caused by levels of neurological organization are quite different from stages caused by levels of biological organization. Neurological levels do not require a new biological behavior guidance system to coordinate the behavior of the lower level organisms, because the parts are neurons or systems of neurons and their behavior is already coordinated by the multicellular biological behavior guidance system. That is what enables them to guide the behavior of the animal.

Though there are as many as seven levels of neurological organization, the last three also depend on a higher level of part-whole complexity in the biological series as well. The level of biological organization above multicellular animals will be called the “social” level, and as we shall see, when the nervous system is used as a biological behavior guidance system to coordinate the behavior of the multicellular animals, what evolves are a kind of organism that will be called a “spiritual animal.”

Three of the levels of neurological organization occur only in spiritual animals, and thus, there is an important difference between two parts of that series of levels, the levels of neurological organization in multicellular animal behavior guidance systems and the levels of neurological organization in spiritual animal behavior guidance systems.

In order to keep these levels of organization straight and to provide a map of the overall course of evolution, all the relevant levels of part-whole complexity are catalogued here. And before tracing the individual stages, I will look ahead to what spatiomaterialism implies about the evolutionary stages involve in each series of levels of organization.

Levels of biological organization. The levels of biological organization involve a series of levels of part-whole complexity of the basic kind sketched above, that is, levels of part-whole complexity in primary structures. In each case, the organisms that evolve at one stage of evolution are the structural causes that are bundled together as a higher level organism that begins the next stage, and what evolves at the higher level is a mechanism that coordinates their behavior, including their reproduction.

Proto-organismic level: RNA molecules. The “organisms” on the lowest level of biological organization are RNA molecules. The structural causes bundled together in them are (or at least include) the triplets of four different kinds of nucleotides that have become the so-called genetic code. Such parts are organized (bonded by a sugar and phosphate backbone) as an RNA molecule, and that chain of links is all that “coordinates” the behavior of these simplest organisms to generate both the reproductive and non-reproductive work that is required to go through reproductive cycles.

The RNA molecule can reproduce as a whole by a two stage process in which each nucleotide attracts a complementary nucleotide so that the complements become bound as parts of a second RNA molecule, and then the same process occurring in the second RNA molecules results in an RNA molecule like the original.

The distinctive structural global regularity that each such unit of the genetic code generates (that is, its non-reproductive work) is to help prescribe which kind of amino acid would be added to the protein molecule being synthesized (by a peptide bond linking them all in a chain of amino acids).

Though RNA molecules satisfy our definition of the kind of material structure that goes through reproductive cycles, that is, a primary structure, it is something of a stretch to think of them as organisms. But as we shall see, there is indeed a way, in a spatiomaterial world like ours, in which RNA molecules would inevitably go through regular cycles in which they generate both kinds of structural global regularities (reproduction and the non-reproductive work of directing the synthesis of proteins). They start out simple, uniform and weak, but gradual evolution by reproductive causation would make them complex, diverse and powerful. The most important power that would evolve during the first stage would be a reliable and efficient way of synthesizing protein molecules (the molecular machines by which traits in all living organisms are generated).

Prokaryotic level: DNA molecules. The minimal organisms at the second level of biological organization are DNA molecules. The structural causes bundled together in them as a higher level “organism” are the organisms (or primary structures) from the lower level, and once again, being linked together as parts of the same macromolecule is all that coordinates their behavior at first. Instead of being made up of RNA molecules, DNA molecules are made up of variants on them, called genes (with a substitution for one of the four kinds of nucleotides used in RNA and a slightly different sugar and phosphate backbone). Each DNA molecule is actually two strands of complementary nucleotides that are most stable when attached to one another, forming the now famous “double helix” structure. But they have both kinds of structural effects that are essential to primary structures, reproduction and non-reproductive work of various kinds.

DNA molecules can reproduce as a whole in much the same way as RNA molecules (though the two complementary strands must unzip and reproduction requires the assistance of a certain protein molecule).

The structural causes bundled together in them are called “genes,” and each gene does its non-reproductive work in much the same way as the RNA molecule as a whole. But since the RNA structures are contained as segments of a DNA molecule, each segment must first be transcribed as a messenger-RNA molecule (mRNA) and only then can it use the highly reliable process inherited from the first stage of evolution (requiring the use of ribosomes and transfer-RNA) to synthesize a certain kind of protein.

Though at first the behavior of these RNA level organisms is coordinated merely by being parts of a single DNA molecule, new mechanisms of coordination are added with the evolution of proteins that are able to repress, promote and de-repress the transcription of specific mRNA from specific segments. As products of a radical random variation, DNA molecules would have to start out simple, uniform and weak. But since there is, as we shall see, a way in which DNA molecules would inevitably go through entire reproductive cycles, their population growth would eventually make resources scarce and natural selection would be imposed. As they became complex, diverse and powerful, DNA molecules would eventually surround themselves by cell walls, controlling the behavior of their lower level organisms more completely, and eventually, as we shall see, there would come a point at which it would be obvious that life had begun. Extant remnants of this stage are prokaryotic cells, such as bacteria, cyanobacteria and archeabacteria.

Eukaryotic level: the nucleus. The minimal organisms at the third level of biological organization are cells with a nucleus, for the structural causes that are bundled together in them are organisms from the next lower level or their equivalent (that is, DNA level primary structures). Indeed, lower level organisms are bundled together in two ways, first, as multiple chromosomes in the nucleus, and second, in most kinds of nucleated cells, as organelles in their cytoplasm, either both mitochondria and chloroplasts (in plant-like cells) or just mitochondria (in animal-like cells). Though the organelles are basically just stripped down prokaryotic cells whose behavior is controlled by the eukaryotic cell, the nucleus is a new mechanism for coordinating the behavior of the DNA molecules in chromosomes (that is, a new biological behavior guidance system), and it generates both kinds of behavior that are essential for a reproductive cycle.

Mitochondria and chloroplasts reproduce themselves in the cytoplasm, but the chromosomes are reproduced in an elaborate process including the entire nucleus, though in both cases it basically is just a form of DNA reproduction from the previous level. We will consider how such a complex mechanism as the nucleus could evolve from prokaryotes.

The nucleus is a mechanism for coordinating the expression of genes on a number of different chromosomes at once, and thus, the cell does non-reproductive work by marshaling an army of non-reproductive structural effects of many lower level organisms (each transcribing various mRNA molecules which then guide the synthesis of proteins). And under the direction of the cell, the self-reproducing organelles generate non-reproductive secondary effects in the same way as prokaryotes.

Since eukaryotes come to exist as a radical random variation on prokaryotes late in their stage of gradual evolution, eukaryotes start out simple, uniform and weak. But as they impose natural selection on themselves by their own reproduction, they become complex, diverse and powerful. Perhaps the most significant contribution to subsequent evolution is the evolution of a process of sexually mixing chromosomes during reproduction. The speed of evolutionary change is accelerated by routinely shuffling lower level primary structures, if only because that makes it possible to combine in a single organism new powers for controlling relevant conditions that were acquired by different organisms in previous generations. But the evolution of sexual reproduction also makes the death of individual organisms inevitable.

Multicellular level: the mechanism of embryological development. The organisms at the next level of biological organization are so obviously made up of organisms from the previous level that it has given them their name. No one doubts that multicellular organisms evolved from single-celled eukaryotes, called “protists,” though multicellular organization is basically different in plants and animals and it evolved many times in plants.

Reproduction in this case usually comes, however, not from all the parts reproducing as parts of the whole (though such asexual reproduction is possible in multicellular plants and many simpler multicellular animals), but by sexual reproduction of egg cells followed by their asexual reproduction. The behavior of the daughter cells can be coordinated by their exchanging messenger molecules (hormones), though in animals, it also involves a mechanism of embryological development that determines daughter cells so that they also move around relative to one another in order to set up the structure of the animal body.

Multicellular organisms do the non-reproductive work of controlling relevant conditions by coordinating the non-reproductive structural effects of its member cells. Such coordination also depends on the exchange of messenger molecules, though in multicellular animals, there is a special organ of cells, the nervous system, for coordinating the cells involved in generating behavior directed at other objects in space.

Originating as radical random variations, multicellular organisms start off simple, uniform and weak, and we have seen how gradual evolution would make them complex, diverse and powerful. The most spectacular product at this level of biological organization is animals with all of the levels of neurological organization mentioned below, for that makes a new kind of animal possible at the social level of biological organization.

Social organisms: language. The most obvious way in which there is a higher level of part-whole complexity than multicellular organisms in the biological series are insect colonies. But there are other examples of colonial animals, such as hydrozoa and blind mole rats, not to mention plants, such as aspen trees, in which whole groves reproduce like multicellular plants. Insect colonies are, as we shall see, an anomalous kind of animal, because they use the same mechanism to coordinate the behavior of multicellular animals as parts of a social level organism that multicellular animals use to coordinate their cells.

That is, insect colonies reproduce as a whole, with a queen having offspring that population the whole colony, and the behavior of different members of the colony is controlled by the exchange messenger molecules called “pheromones.”

But colonial animals are not the only kinds of organisms on the “social” level of biological organization. Another and more distinctive example is human society, and its way of coordinating multicellular animals is language, which depends on the prior evolution of all the levels of neurological organization. The spiritual animal is, as we shall see, a unique level of organization. Among other things, the same, language-based behavior guidance system is both a social level biological behavior guidance system and the new kind of animal behavior guidance system that is made possible by the social level of biological organization.

Levels of neurological organization. The other way that multicellular animals lead to a further series of evolutionary stages is less radical, because it does not involve levels of part-whole complexity in primary structures, that is, in complex material structures that reproduce themselves like organisms. Instead, the structural causes that are bundled together as material structures at a series of levels of part-whole complexity occur within the structure of a single organ of multicellular animals, the nervous system, whose function is to guide animal behavior. The elementary structural causes in this case are neurons, and they behave by “firing” (that is, sending an action potential along its long axon to other neurons affecting whether they fire). The higher levels of part-whole complexity are mechanisms made of many neurons, mechanisms made of many such mechanism, etc.

The levels of neurological organization are basically different from levels of biological organization, because it is not necessary for the new level of organization to coordinate the behavior of its own parts, and certainly not to coordinate their reproduction. That would be required, if it were a biological behavior guidance system. But in this case, the higher level structures is an animal behavior guidance system. What coordinates the behavior of neurons in setting up the nervous system is the mechanism of embryological development, and though neurons do reproduce in that process, the higher level neuronal structures do not. Since the structure of the nervous system is provided for it, the animal behavior guidance system can use that structure as an ontological cause, that is, as a machine, to guide the behavior of the whole animal in acting on other objects in space.

Behavior guidance depends on another kind of behavior distinctive of neurons, namely, “firing” (that is, sending an action potential along its long axon to other neurons affecting whether they fire). Neurons are organized into higher levels of part-whole complexity when the firings of certain neurons in entire groups affects the firings of other groups of neurons, or systems of such groups affect other such systems, etc.

It is not necessary for the relevant material structures at each level of neurological organization to go through reproductive cycles on their own in order to become naturally perfect in the sense of doing the most with the least like perfectly efficient machines, because their gradual evolution in the direction of maximum holistic power is the effect of reproductive causation on the multicellular animals of which they are part.

Whatever their level of neurological organization, such material structures serve specific functions in guiding animal behavior and, at each level of neurological organization, the material structures are shaped to be as powerful as possible in controlling some relevant condition with the fewest and simplest neurons. If, therefore, a series of levels of part-whole complexity were possible in the nervous system, it would generate another series of evolutionary stages during the stage at which multicellular organisms evolve.

The series of levels of neurological organization are divided into two distinct series, because after a certain point in the evolution of the brain, higher levels of neurological organization depend on a higher level of biological organization as well, that is, the evolution of a new kind of animal at the social level. I will, therefore, list the two series of levels of neurological organization separately.

Animal levels of neurological organization. The first series of evolutionary stages caused by levels of neurological organization occurs in multicellular animals whose evolution depends only on natural selection at the level of individual animals.

Somatosensory animals. Somatosensory animals are the simplest multicellular animals, including hydra and sea stars, which interact with other object in space only by contact. In the, single neurons (and their firings) serve the three basic subfunctions in guiding animal behavior: (1) registering sensory input, (2) selecting how to behave, and (3) generating motor output. Such nervous systems are not centralized.

Telesensory animals. Telesensory animals are the simplest animals that can sense objects at a distance from their bodies, and in them, systems of neurons (at least ganglia or two dimensional arrays of neurons in the neural tubes of vertebrates ) serve the three basic subfunctions in guiding animal behavior. The eye’s retina, for example, requires many neurons working together to generate an image of objects at a distance, and locomotion in relation to a distant object requires a system of many neurons to send motor commands simultaneously to all parts of the body. Such centralized nervous systems are found in all the vertebrates mentioned above, from fish to birds, as well as most kinds of invertebrate animals, such as worms, mollusks, insects. “Telesensory animals,” as I will call them, see the whole world around them as the object on which their behavior might act.

Subjective animals. Subjective animals are animals with spatial imagination, namely, mammals. In them complete circuits of systems of neurons serve each of the basic subfunctions in guiding animal behavior (registering sensory input, selecting how to behave, and generating behavior). The distinctive mammalian neocortex marks the shift of behavior guidance responsibilities from the midbrain and hindbrain to nervous mechanisms in the vertebrate forebrain, and as we shall see, by using one circuit of systems of neurons to register sensory input (as the “local image”) and another such circuit to generate bodily behavior, including locomotion (as the “body image”), mammals have evolved a faculty of spatial imagination that enables them to think coherently about how locomotion (and motion) affect the relations of objects in space.

Motor commands can be generated in the “body image” with their effects on the actual body suspended. Such “covert locomotion” calls up memory images of what was previously perceived in the same situations in the “local image,” and so the mammal is able to imagine how certain kinds of locomotion would change the spatial relations of objects in space before acting overtly.

Spatial imagination makes both their own body and other objects in space appear to them as a natural world, and thus, such animals will be called “subjective animals.” Since they have a conception of space, they see the object as located in space and they can understand the effects of motion on spatial relations.

Manipulative animals. The best, if not only, example of manipulative animals are higher primates. A yet higher level of part-whole complexity in neural mechanisms gives them a faculty of structural imagination for thinking about the geometrical structures of objects in space and how they change as a result of manipulation. In addition to the interaction of the “body image” and “local image” circuits that gives mammals generally spatial imagination, each hand must have a comparable system in which a “hand image” interacts with an “object image” to represent the effects of manipulation on the object. Structural imagination is contained within spatial imagination so that the object being handled is seen as located in the subjective animal’s conception of space. With four hands and a body, there are five sets of interacting circuits in the primate brains, giving what I will call “manipulative animals” a yet higher level of neurological organization than subjective animals. They see the object in space as having a geometrical structure.

Spiritual levels of neurological organization. The series of levels of neurological organization in multicellular animals continues in animals that become parts “spiritual animals.” Multicellular animals are the lower level organisms that get bundled together as parts of a higher level organism that goes through reproductive cycles as a whole, on the social level of biological organization. But spiritual animals are radically different from insect colonies, the other social level animals mentioned above, because instead of using the mechanism of embryological development (the biological behavior guidance system from the multicellular level) to coordinate the behavior of the constituent multicellular level organisms, the spiritual animal uses a basically new mechanism, namely, language. The use of language serves both as a biological behavior guidance system (coordinating the behavior of lower level organisms as parts of a higher level organism that goes through reproductive cycles as a whole) and as an animal behavior guidance system (guiding its behavior like an animal at the social level of biological organization). That makes this social level animal unique, and since it has no body except the independently moving bodies of its biological parts, it is aptly called a “spiritual animal.”

The use of language requires, however, a level of neurological organization higher than that of primates. Because of that function, the levels of neurological organization are evident in levels of part-whole complexity in the structures of the linguistic representations they use to coordinate behavior.

Primitive spiritual animals. Linguistic representations at the level of “natural sentences,” with a simple subject-predicate grammar, make it possible to coordinate behavior in nomadic groups of primates, called “hominids.”

A higher level of neurological organization is required for the capacity to generate and understand natural sentences, because not only must covert manipulative behavior be able to combine multiple object images as representations of states of objects in space, but the animal must also be able to generate (and understand) verbal behavior that indicates the kinds of covert behavior involved in constructing the natural representation. That is, linguistic behavior has both a verbal and a nonverbal side.

Such a brain mechanism can serve as a spiritual behavior guidance system, because when a leader assigns different tasks to different members in a public process, not only does each member know what he is supposed to do in a plan of group action, but all the members know what everyone is supposed to do. The same plan of group action is then contained in each of the brains of the members. That is how their behavior can be coordinated in attaining a single goal.

The spiritual animal has both kinds of structural effects required to go through reproductive cycles as a whole on the social level.

The spiritual animal behaves like a manipulative animal at the social level, that is, with each member acting like a distinct hand in concert with the others as part of a common plan for acting on objects in space.

But such spiritual animals can also reproduce as a whole, because the members can all reproduce sexually at the individual level and, when its population becomes too large, the nomadic band can divide into groups that go different ways.

Thus, spiritual animals multiply in space, make resources scarce, and thereby impose natural selection on themselves, so that they evolve by reproductive causation toward natural perfection of organisms of their kind.

Rational spiritual animals. Linguistic representations at the level of “psychological sentences” make subjective animals reflective, and that gives spiritual animals and their members the power of reason.

Psychological sentences take words referring to subjective animals (or spiritual animals) as their grammatical subjects and predicate of them verbs of propositional attitude, such as “perceive,” “believe,” “desire,” and “intend,” followed by a sentence indicating the proposition to which the attitude is taken. Psychological sentences are able to represent the causes of behavior (and beliefs) in subjective animals, and the use psychological sentence makes linguistic animals reflective, because it enables them to use the functioning of their own brains to imagine the behavior guidance processes going on in other brains. They are eventually able to use psychological sentences to represent the causes of their own behavior (and beliefs) as causes in the very process of causing that behavior (or belief), and since that affords a new, reflective level of control over brain processes and the behavior it generates, the causes come to be called “reasons.” Thus, the use of psychological sentences eventually leads to reason.

At this level of linguistic (that is, neurological) organization, not only is language used by a leader to assign tasks, but the linguistic representations exchanged among members of the spiritual animal have the structure of arguments, that is, conclusions about what to do (or believe) together with a reason for them. Thus, in addition to making both the individual and the spiritual animal more powerful, the use of psychological sentences is the foundation for a new form of evolution by reproductive causation to take place, namely, cultural evolution.

In this case, the “organisms” are arguments (with the component sentences serving as the structural causes bundled together in them). The non-reproductive structural effect of argument is to guide behavior (or beliefs). Arguments reproduce when one member convinces another to accept it. Arguments impose natural selection on themselves because the brains into which they can reproduce are finite. And which arguments succeed in reproducing is not just chance, because individuals can judge which among competing arguments is most coherent, given everything they know. Hence, arguments are subject to rational selection and tend to evolve.

Thus, at the rational spiritual level of neurological organization, there is an evolution of the arguments accumulated as the cultures of spiritual animals, and as we shall see, it is change in the direction of natural perfection for arguments (or reason). Arguments have maximum holistic power for “organisms” of their kind when they discover the true and the good.

Philosophical spiritual animals. Linguistic representations at the level of philosophical arguments lead to a step-like increase in the power of reason to discover the true and the good. Philosophical arguments are a higher level of part-whole complexity in linguistic representations, because philosophy uses a foundation to defend more fundamental truths about the world. In one way or another, philosophical arguments try to explain why the other arguments that have accumulated in the culture of rational spiritual animals are valid, ands that gives philosophy a higher level of forensic organization.

There are, as we have seen, two, basically different ways of making such a higher level argument, epistemological philosophy and ontological philosophy. Epistemological philosophy uses a theory about the nature of reason that comes from reflecting on how rational beings like us know to prove that certain ordinary conclusions about the true and the good are correct (or false). Ontological philosophy uses an empirically justified ontological explanation of the world as its foundation for explaining the validity of the ordinary arguments of the rational spiritual level. (Though that leads to an explanation of the nature of reason, its explanation of the nature of reason is not the foundation of ontological philosophy, but just one of its implications.)

The simplest and most natural way to construct such a higher level argument is the ontological approach, but it cannot succeed until natural science has evolved. Thus, the first approach to philosophy to prosper for long is the epistemological approach, and though it inevitably fails on its own (mainly because of how realism leads to ontological dualism and dualism leads skepticism), it gives rise to natural science, eventually making it possible for ontological philosophy to succeed.

There are, therefore, two phases in the evolution of philosophical spiritual animals. They do not reach the maximum holistic power for “organisms” of their kind until ontological philosophy succeeds in making the fullest use of this level of neurological organization.

Though philosophical arguments do not require any change in the brain structures set up by the mechanism of embryological development, they do involve the acquisition of a higher level of neurological organization in the individual brain. But it comes from process of learning language and the arguments that have been accumulated as culture.

However, there is yet another kind of series of stages in the evolution of spiritual animal, because there are levels of part-whole complexity in the social structures (as opposed to cultural structures) of spiritual animals. Among them there is, in addition to cultural evolution, another form of reproductive causation at work on “organisms” constituted by evolved structures (including the evolution of class structure and eventually capitalism, which is a third form of reproductive causation that takes place on the social level). The combination of these various stages of evolution entail a philosophy of history in the 19th Century style. But I will leave those evolutionary stages and their complications for the next section, when we trace the course of evolution through all of its stages in detail, from its beginning through the history that still lies in the future.

Ontological effect: Stages of evolution.Levels of part-whole complexity in evolving organisms, described in the previous section are the ontological cause of another reproductive global regularity, namely, stages of evolution. It is a regularity that shows up over longer periods of time than the first, because it is a series of stages, each of which is the gradual change of organisms of some kind in the direction of their natural perfection (and the natural perfection of the ecology they help make up).

At each stage, some kind of organism starts off simple, uniform and weak and gradually becomes increasingly complex, diverse, and powerful. But evolution does not stop when they attain the natural perfection for organisms of their kind, if it is possible for those organisms (or important structures within them) to become, in turn, multiple structural causes bundled together in an organism with a higher level of organization that goes through reproductive cycles as a whole. If such a radical random variation is possible, it will eventually be tried out, and such higher-level organisms will also impose natural selection on themselves by their own reproduction. That will start another long stage of gradual evolution, because the part-whole complexity in their structures would make it possible to try out and accumulate a very wide range of traits.

Since one stage leads to another, the overall course of evolution is a ratchet-like series of stages of gradual change, each punctuated by a more radical, revolutionary change that begins a new stage of gradual change by trying out organisms with a higher level of part-whole complexity. The way that higher levels depend on the prior evolution of lower levels means that such evolutionary stages can occur only in a certain order, from simpler to more complex, working its way up the levels of organization. That gives evolution an overall direction that could well lead up to beings like us and, perhaps, beyond.

Reproductive causation can explain, therefore, punctuated equilibria and the enormous variety of organisms. Though reproductive causation implies that the gradual evolution at each stage leads to an evolutionary equilibrium, it also explains why such equilibria are punctuated. The punctuations occur when the natural perfection of organisms on one level of part-whole complexity makes it possible for random variations to try out organisms with a higher level of part-whole complexity (either higher levels of primary structures or higher levels of important structures set up by them, such as in the nervous system). And since their higher level of organization enables them to try out a wide range of new traits as random variations that can be accumulated and fit together harmoniously for controlling the conditions that affect their reproduction, a new stage of gradual evolution would begin, leading to another evolutionary equilibrium.

Moreover, if new stages of evolution can be explained by the higher levels of part-whole complexity in evolving organisms mentioned above, reproductive causation can also explain the variety and complexity of existing organisms. In addition to the many varieties of organisms that come to exist at each stage as they divide up the various sources of free energy and become more diverse, it implies that there are differences among organisms that come from their level of part-whole complexity, with each level initiating a radiation of kinds filling all the available ecological niches.

Since this explanation of evolution follows from our ontological foundation, however, its implications about evolution are ontologically necessary truths. They hold in any spatiomaterial world like ours (that is, where matter has a nature that explains ontologically the basic laws of physics and the universe has a large scale structure with planetary systems). Reproductive global regularities are among those necessary truths, including revolutionary episodes in evolution and the evolutionary stages they involve. The ontological cause of revolutionary evolution has been described: each new stage is the evolution of organisms with a higher level of part-whole complexity. But in order to prove that this more complex aspect of the basic reproductive global regularity is a necessary truth, the ontological cause must be shown to entail the effect. That is, it must be shown that each new stage is inevitable, given the previous stage. That is what is done in each of the ten following sections. But the arguments will all be of the same kind. In each case, the inevitability of the next stage of evolution is proved by showing that the relevant higher level of part-whole complexity is both possible and functional.

Possibility of higher level of part-whole complexity. In order to show that a stage of evolution is inevitable, it must be shown that it is possible for organisms with a higher level of part-whole complexity to go through reproductive cycles as a random variation on the organisms that have already evolved. What is possible depends on what already exists, which, except for the first stage of evolution, includes whatever is provided by the natural perfection of organisms and ecology at the previous stage. Thus, the first task at each stage is to show how the outcome of the previous stage of gradual evolution makes possible the radical variation that bundles the lower level organisms together as a higher level organism. It must do so in a way that explains how the higher level structure can coordinate the behavior of the lower level organisms to generate both essential kinds of structural effects, reproduction and non-reproductive work, in one cycle after another. It is not always obvious how that is possible, especially at the first two three stages of evolution and in the case of the evolution of spiritual animals.

Function of higher level of part-whole complexity. Another stage of evolution would not follow, however, even if organisms with the higher level of part-whole complexity can be "tried out" in this sense, unless the higher level enables the organisms to control new conditions that affect reproduction. In order to evolve by reproductive causation, they must be able to control conditions that are beyond the reach of organisms at the lower level of part-whole complexity, or else they will not be able to compete with existing organisms. Indeed, there must be an entire range of powers that they alone can evolve in order for them to go through a stage of gradual evolution and become naturally perfect of their kind. The source of the increased power may be obvious in the earliest and latest stages, but it is less obvious in the case of the levels of neurological organization which fall in the middle.

In order to show that all the stages are inevitable, however, it will not be enough to show that each stage is inevitable, given the natural perfection of organisms during the previous stage. It will also be necessary to identify certain major accomplishments of gradual change at each stage of evolution, because certain powers included in their natural perfection are what make it possible to try out the radical random variation that makes possible the next stage. That is how each stage contributes to overall course of evolution.

In the following sections, we shall derive the ten stages of evolution that lead up to rational beings like us. We shall see, in other words, how one stage of gradual evolution makes the next stage inevitable, staring with the beginning of evolution and tracing a series of stages that leads up to beings like us. The relevant levels of part-whole complexity in the structures of organisms have already been identified, and since each new stage is the evolution of the next higher level, we already know that they occur in a certain necessary sequence, if they occur at all. Thus, it remains to be shown that they do inevitably occur, and that will accomplished by showing that each is both possible and functional, given what is accomplished at the previous stage.

Though it is possible, in principle, for such a derivation to be formally compelling, what follows is only the outline of such an argument. Though the possibility and function of the level of organization that evolves at each stage will be shown, we shall not show what the natural perfection of organisms of each kind is by tracing the long course of gradual evolution. Instead, we shall use what has evolved on earth to tell what is naturally perfect (since it is ontologically necessary that gradual change in the direction of natural perfection occurs). And in some cases, the possibility of trying out the higher level of part-whole complexity will be only be shown to be probable. That is to leave the project of formulating this argument as a logical deduction until later, but it will identify the conclusions of those yet-to-be-constructed ontological arguments.

Though we shall follow out a series of stages that begin with biological evolution itself and lead up to beings like us, that is not to deny that there are other stages involved in the evolution of life on earth. Not much attention will be paid, for example, to the evolution of plants. And there may by other series of stages that branch off in other directions. But the one we shall trace is the most important one, because it leads to the organisms with the greatest power.

Natural perfection of life. The proof that evolution goes through a series of inevitable stages is proof that evolution by reproductive causation is change in the direction of natural perfection in a far grander sense that the natural perfection of organisms and ecology, which are the direction of gradual evolution at each stage. It is an additional form of natural perfection, which implies that each new stage has a function and is good in virtue of contributing the natural perfection of the whole of which it is part. I will call the increase in such levels the “natural perfection of life,” because each higher level of part-whole complexity in the natural perfection of organisms enables life generally to control a wider range of relevant conditions

Furthermore, if we recognize that evolution by reproductive causation is itself a kind of natural perfection because of how it makes the most of substances by using their endurance through time to bring about the natural perfection of organisms, the ecology and life itself, then each stage of gradual evolution (like each phase within each stage) also has a function and is good in virtue of making an essential contribution to the natural perfection of the whole of which it is part.

The natural perfection of life is a form of natural perfection of by our definition of doing the most with the least. In this case it does the most because it brings more and more conditions in the world under the control of living organisms (as structural causes), and it does it with the least, because the organisms with which it does so have the natural perfection of organisms and they are parts of an ecology that has the natural perfection of ecologies. This is not to say that life becomes absolutely perfect in this sense, but only that it is change in the direction it would have to go in order for life to be absolutely perfect in the sense of doing the most with the least. We will see in the chapters on What ought to exist what kind of perfection it leads to in the end.

It should be emphasized, however, that although higher level organisms would evolve only if they were more powerful in some way, that does not mean that organisms from lower levels must stop going through reproductive cycles on their own alongside the new organisms. The natural perfection of the ecology at later stages includes organisms from all previous stages, completing reproductive cycles side by side.

As we have seen, the varieties of organisms that come to exist during each stage tend to mirror the physical sources of free energy available in the region, and some sources are so limited that lower level organisms are more efficient in tapping them than higher level structures. They cannot easily be displaced by higher level organisms.

Moreover, though the advent of higher level organisms may displace lower level organisms from niches with larger sources of usable energy, they also provide new sources of usable energy for lower level structures to invade, for example, in their wastes, decaying bodies, or as diseases (such as viruses, bacterial infections, and eukaryotic parasites in multicellular organisms).

Thus, as higher level organisms of some kind are evolving toward natural perfection for organisms of their kind, there is also gradual evolution of organisms with all levels of part-whole complexity in the direction of the natural perfection of the ecology at that stage. Each species imposes natural selection on itself, and since organisms with different levels of part-whole complexity go though reproductive cycles side by side, they all become increasingly diverse and powerful, dividing up the free energy available among themselves to fuel their reproductive cycles. (As we shall see, the natural perfection of both the organisms and the ecology are usually involved in making the next stage possible.)

Biological stages of evolution. The basic series of levels of part-whole complexity in evolving organisms is the series of levels of biological organization, and we will use it to follow the course of evolution up to multicellular organisms. We will then take up, in order, the series of stages caused by the levels of neurological organization, including both the stages of animal evolution and the stages of spiritual evolution.

1. Molecular stage: RNA as a proto-organism.One of the biggest puzzles about evolution is how it began. Darwin did not try to explain it, speaking as if God has created the simplest organisms from which all the other species descended, and there is still no agreement on this issue. Indeed, it is sometimes called one of the great puzzles that natural science has yet to solve. But ontological philosophy affords a simple explanation of its beginning.

The beginning of evolution.What would solve this puzzle is a way of showing how the beginning of evolution is inevitable. Given that reproductive global regularities are ontologically necessary, that could be done by showing that, before biological evolution began, there is a region in which the ontological cause of gradual evolution exists, that is, in which there are complex material structures going through reproductive cycles.

Since the ontological cause of gradual evolution involves a kind of material structure that uses free energy to do work, the region in which they exist must be one in which there is a thermodynamic flow of matter (that is, a flow from potential energy through kinetic energy and photons to evenly distributed heat, according to the tendencies to kinetic energy and randomness). Such a region of increasing entropy is provided, as suggested at the end of Material global regularities, by the structure of planetary systems.

Stars involve fusion reactions, a form of the tendency of potential energy to become kinetic energy (and radiation), and thus, they supply free energy. And the surfaces of planets that intercept its radiation are a region within the thermodynamic flow where material structures could be using free energy to do work. Photons interact with molecules on the surfaces of planets, and that can produce molecules with energy-rich structures that supply, in turn, the free energy (as chemical potential energy) to drive many other kinds of interactions among molecules. Much of the energy eventually becomes kinetic energy, and the tendency to randomness distributes it evenly among objects on the micro level as heat (or bound energy) which cannot be used to do work. The planet tends, however, to have a certain temperature range, because it radiates low energy photons back out into the cold emptiness of space.

Since the right kind of region exists in planetary systems, all that is required for evolution to begin are organisms going through reproductive cycles. That may not seem possible before biological evolution begins. The surface of such a planet is composed only of naturally occurring molecules (that is, the kinds of material structures that come to exist naturally as a result of the tendency of potential energy to become kinetic). But even the simplest forms of life, such as bacteria and other prokaryotes, have a structure that is far too complex and functional to have occurred originally as a accident in the motion and interaction of molecules on the surface of a planet.

Organisms are nevertheless possible on the surface of such a planet, because what we mean by “organisms” is a complex material structure of the kind that can go through reproductive cycles and that can be surprisingly simple.

Organisms are complex material structures because they are bundles of structural causes with various structural effects. And to say that they can go through reproductive cycles is to say that these material structures can reproduce themselves as well as generate those structural effects as non-reproductive work. If they actually go through reproductive cycles, it is, as we have seen, ontologically necessary that such “reproducing organisms” will evolve toward maximum holistic power for organisms of their kind.

The ontological cause of gradual evolution we are seeking, therefore, could be as simple as a single molecule going through reproductive cycles. It would have to a rather complex molecule, but if it is possible, such a molecular level organism might be called a “proto-organism.”

The inevitability of evolution beginning. Given that there are regions where free energy is continuously supplied to molecules, what makes it ontologically necessary that such proto-organisms exist in a spatiomaterial world like ours is that the specific nature of matter makes matter is capable of forming itself into molecules of sufficient complexity (through the tendency of potential energy to become kinetic). We know that it is possible for molecules with complex enough geometrical structures to be proto-organisms, for we can conceive how a certain kind of molecule would be such an ontological cause.

Of course, knowing the molecular processes involved in life on earth makes it easier to think of this possibility. But it is clear that molecules are the simplest kinds of material structures that could possibly be the original bundles of structural causes going through reproductive cycles, because the natures of nucleons and electrons make only a few structures possible in atoms.

Given the nature of the ontological cause of gradual evolution, all that is necessary is that a molecule have multiple parts, each of which is the structural cause of both essential kinds of work, one by which it reproduces itself and one by which it helps construct another molecule — assuming that it actually goes through reproductive cycles in which it normally does both. It is possible for a macromolecule to have both kinds of structural effects, because it is a long chain of simpler molecules of a few kinds and there is a simple way that segments of such a molecule could do such basically different kinds of work.

Assume that matter is capable of enough complexity that the simpler molecules that are linked as parts of a macromolecule can form weak bonds (such as the hydrogen bond) with other simple molecules. And assume that when they attract the other simple molecules, the other simple molecules become linked to one another as a second macromolecule (with strong chemical bonds). There could then be parts of such a macromolecule that are capable of doing both essential kinds of work.

The macromolecule could reproduce itself when each simple molecule in the chain did such work on molecules of its own kind. And it could do non-reproductive work when short segments of such simple molecules in the chain did such work on molecules of a basically different kind, for that would be to construct another kind of macromolecule, whose structural effects would be the work it does. (See accompanying diagram of proto-organism as a bundle of structural causes each with two kinds of essential structural effects.)

Proto-organisms of this kind can be said to have a higher level of part-whole complexity than ordinary molecules, because they must have parts that are capable of doing both kinds of work. Those parts are the structural causes that are bundled together as a complex material structure that goes through reproductive cycles as a whole, and as depicted in the diagram, each structural cause is composed of three of the simple molecules that make up the proto-organism.

That puts proto-organisms on a rather high level of what has been called the “ladder of nature.” Even if we count all subatomic particles as being on the first rung, that puts atoms on the second rung, and since ordinary molecules are a third rung, proto-organisms would be a fourth rung. But it would be higher, if we took into account the levels of part-whole complexity among the parts of atoms, for setting aside the electrons, the nucleus of an atom may be composed of many nucleon, and each nucleon is composed of three quarks. These lowest rungs on the ladder of nature are relevant here, for as we shall see, each of the levels of biological organization above the original proto-organisms is another level of part-whole complexity and, thus, another rung on the ladder.

If any macromolecules that can serve as proto-organisms occur naturally on the surfaces of suitable planets,, there are probably at least several kinds of them, because it is a world in which matter has a nature that enables atoms to constitute molecules that are sufficiently complex and stable. Now, we know that it is ontologically necessary that, if proto-organisms were to go through reproductive cycles regularly for a long period of time, they would change gradually in the direction of maximum holistic power for proto-organisms of their kind. But that final condition could also be satisfied on planets that are not only in orbit around a star, but also rotating on their own axes.

The circadian cycle on the surface on the planet involves a regular change in the supply of free energy, and that is a way that at least some kinds of proto-organisms would be driven through reproductive cycles. Any kinds of proto-organisms that tended to do one kind of work during the day (when free energy was more abundant) and the other kind of work during the night (when less free energy was available) would go through reproductive cycles indefinitely. Hence, they would inevitably evolve.

Which kind of proto-organism would be responsible for the subsequent evolution on the planet (and thus, perhaps, how far evolution can go) would depend on which kind of macromolecule is most susceptible to this influence of the cycle of night and day and which kind had non-reproductive work that was most capable of controlling relevant conditions. We know which kind it is from what has actually evolved on earth. But what we know from the ontology alone is that there is a way in which it could be inevitable throughout the universe that macromolecules evolve in the direction of maximum holistic power for proto-organisms of their kind. It depends only on the large scale structure of the universe and the nature of matter, and since we know that those conditions are satisfied in our spatiomaterial world, we know there is a way that the beginning of evolution could be inevitable.

Thus, I shall take it to be an ontologically necessary truth that in a spatiomaterial world like ours it is inevitable that evolution by reproductive causation begin. It is not a logical consequence of spatiomaterialism itself, because it also depends on the specific nature of matter and structure of the universe. (We have assumed, for example, that matter is capable of such complexity that other naturally occurring macromolecules could serve as possible proto-organisms). But a conditionally necessary truth is sufficient for my present purpose, since I am merely outlining the ontological argument that could eventually show that the beginning of evolution is inevitable on earth. However, we must now consider how likely it is that the actual world satisfies those further conditions.

RNA as the original proto-organism on earth. Knowing how the beginning of evolution could be ontologically necessary, we know what to look for to discover whether it was inevitable that evolution begin on earth. We know that evolution did occur on earth, and thus, if it did begin with molecules of some kind serving as proto-organisms going through reproductive cycles, we can identify the specific kind of macromolecule in the molecular structure of the organisms on earth. Not surprisingly, it turns out to be RNA molecules. If we now see how RNA would play the role required by the foregoing ontological argument, we will learn something new about the nature of RNA.

Despair about explaining how RNA can evolve has, however, led some to look in entirely different directions to explain the origin of evolution. For example, some think it must lie in larger configurations of molecules, such as coacervate droplets, or micro spheres made of protein molecules, that naturally form in water. Others look favorably on even more extreme solutions, such as panspermia, the belief that the structure required for life is spread throughout the universe in the form of seeds, which grow on young planets.

RNA molecules are made up of some four different kinds of simpler molecules, nucleotides, linked together in long chains (by a sugar and phosphate backbone). What makes such macromolecules a likely candidate is that they reproduce their own structures when supplied with nucleotides, albeit inefficiently. (Each nucleotide exerts weak forces by which it attracts a complementary nucleotide so that the latter becomes attached to the new chain, and thus, after two rounds of reproduction, there is another RNA molecule of the same kind as the original.) But RNA molecules could be bundles of structural causes that also do non-reproductive work, because short segments of adjacent nucleotides could work together under different circumstances to attract simple molecules of another kind so that the latter also became attached to one another in long chains. (That is, different triplets of nucleotides could determine different kinds of amino acids in protein synthesis.) If RNA molecules are the bundles of structural causes that were doing both kinds of work, the synthesis of another macromolecule like themselves and the synthesis of a different kind of macromolecule, they could be the proto-organisms that were going through cycles of reproduction at the beginning.

If this is what RNA molecules were doing, they would not only be proto-organisms, but since they are composed of structural causes that are responsible for both kinds of products (reproducing themselves and determining a kind of amino acid), they would also be able to try out random variations on traits that are heritable by their offspring. Thus, if RNA molecules were to go through cycles in which they normally did both kinds of work, they would inevitably evolve.

Reproduction would cause their population to grow, and population growth would eventually make resources scarce. (The chemical processes by which molecules have effects like these depend on their having a supply of energy-rich molecules, and whatever the ultimate source of energy-rich molecules on the surface of a planet, the supply will be finite in any region during any finite period of time.) Thus, RNA molecules would eventually have to compete for resources to do the work involved in completing a reproductive cycle. Only the fittest would succeed in the end.

The range of variations would be large, for if the structural causes bundled together in these proto-organisms is each composed of three nucleotides from four different kinds, there are potentially as many as sixty-four different kinds of simpler molecules (amino acids) that could be linked together in the secondary macromolecule (the protein molecule). Thus, if the varieties of secondary macromolecules they could produce were potentially useful in controlling conditions that affect their reproduction, they would inevitably evolve greater power.

The primitive non-reproductive structural effect of RNA. This is how the beginning of evolution could have been inevitable. I say “could have been,” because biologists do not know that RNA were able at the beginning to generate the second kind of macromolecule and they must have done non-reproductive work of some kind in order to evolve. What is known is that RNA molecules produce such secondary macromolecules in all extant life forms. RNA guides the synthesis of protein molecules, or chains composed of twenty or so different kinds of amino acids (attached to one another by peptide bonds). And in life forms on earth, proteins are the molecular machines responsible for doing virtually all the work of controlling relevant conditions. But RNA molecules generate this kind of secondary product only in the presence of a very complex structure, called a ribosome, which is composed of many different kinds of complex proteins and other RNA molecules, and no such complex molecular machine could possibly have existed naturally at the beginning of evolution (that is, as a simple product of the tendency of potential energy to become kinetic energy).

The current need for ribosomes does not necessarily mean, however, that RNA was not the proto-organism with which evolution began, because RNA could have had a simpler and much less efficient way of catalyzing the synthesis of proteins under conditions that prevailed on the early planet.

When the RNA backbone was attached to a clay substratum, for example, certain triplets of its nucleotides may have been able to attract a few kinds of amino acids, thereby helping to attach them together in chains. Even a very inefficient way of synthesizing proteins involving only a few kinds of amino acids could have promoted the reproduction of the RNA molecules that synthesized them, for even very simple proteins could make a big difference in completing reproductive cycles. For example, simple proteins could help supply parts needed for reproduction (by preparing nucleotides). And some of the first powers to evolve would have been selected for making the synthesis of proteins more efficient, which would expand the range of possible non-reproductive structural effects. For example, one kind of simple protein might have helped attach RNA backbones to clay at an angle that promotes protein synthesis. Another might attach to RNA in a way that makes the synthesis start at a certain nucleotide, so that the triplet code was read the right way. At later points, new kinds of amino acids (or, perhaps, even the fourth kind of nucleic acid) may have been added to their repertoire, increasing the range of possible powers. Alternatively, other kinds of nucleotides or amino acids may have been going through a similar process, and they may have been left behind by the greater efficiency of the protein synthesis generated by those RNA molecules that are now parts of living organisms. In any case, with natural selection caused by their reproduction (that is, the scarcity due to their population growth), continual improvements like these on a primitive form of protein synthesis could explain where the ribosomes now found in all forms of life come from.

That is how evolution could have begun. That is, nothing known to biology shows that RNA did not have such a primitive way of generating secondary products. And if they did, not only the beginning, but also the course of evolution would be inevitable. As we shall see, such gradual change in the direction of natural perfection together with one episode of revolutionary evolution would explain the origin of life, and from there, it is clearer how it is inevitable that one stage follow another.

The original reproductive cycles of RNA. Assuming that RNA did have a primitive non-reproductive structural effect, it may still seem that evolution could not have begun this way in earth, because in order to evolve, RNA molecules would have to go through cycles continually in which they produced both kinds of molecules, and that hardly seems likely, given the complexity of the process of synthesizing either kind of molecule. The synthesis of either kind of molecule requires a series of steps in which one simpler molecule after another is attracted to the RNA molecule and attached to a growing chain. Thus, the fact that one and the same RNA must generate both kinds of molecules suggests that these two processes are likely to interfere with one another. That makes it seem that RNA could not go through reproductive cycles regularly enough over a long period of time for reproductive causation to have its inevitable effect.

The foregoing ontological explanation of the inevitability of the beginning of evolution, however, includes an explanation of why RNA molecules would have gone through reproductive cycles indefinitely. They were driven through reproductive cycles by the nature of the larger context in which evolution begins.

Earth is a planet, and as is widely assumed, life can evolve only on planets orbiting at the right distance from their stars for water to be liquid. Water provides a medium in which the kinds of chemical interactions on which both kinds of products depend are more likely to occur (if only because water stabilizes molecular structures by limiting the range of energies at which they interact). And radiation from the sun is a source of energy that fuels the chemical interactions that result in the energy-rich molecules used as resources by RNA molecules to generate their two products.

Thus, RNA could have been driven through reproductive cycles by the circadian cycle that occurs on planets that rotate on their own axis as they orbit their star. If RNA were disposed to produce one molecule during the energy conditions that prevailed during the day, and if they were disposed to produce the other kind of molecule during the energy conditions that prevailed at night, they would have gone through one cycle after another in which they generated both essential kinds of molecules (perhaps each of them several times during each cycle).

There is good reason to believe that RNA is susceptible to such an influence, assuming it can generate both kinds of products at all. Its reproduction requires only the free energy contained in the simpler molecules that it uses to construct another molecule like itself. (Nucleotides come with phosphate tails, and breaking them off supplies the energy needed to bond them together.) But the parts attached to one another in protein synthesis do not supply their own energy. They need other energy-rich molecules, which were probably most abundant during the day (such as ATP, or adenosine triphosphate). Thus, RNA could have been driven through cycles of reproduction by the cycle of night and day.

An ontological argument for RNA’s primitive non-reproductive structural effect. The need to assume that RNA had a primitive way of synthesizing protein molecules is the weak link in this demonstration of the inevitability of the beginning of evolution on earth. It is possible that RNA has no such structural effect. Some accident may be responsible for evolution beginning on earth. Or there may be some other way in which it is inevitable. But the capacity of spatiomaterialism to explain other aspects of the world, including, as we shall see, the inevitability of the subsequent stages of evolution, will make it seem likely that many more aspects of the world are ontologically necessary than it now appears to us. And if we suspect that evolution must have had an inevitable beginning, we can take this explanation of how it would be inevitable in a spatiomaterial world to be a reason for believing that RNA does have a primitive way of doing non-reproductive work.

Given the enormous variety of molecules made possible by the nature of atoms and the bonds among them that are stable on suitable planets, there were probably several kinds of macromolecules that could have served as proto-organisms by virtue of being bundles of structural causes that could do both kinds of work, that is, produce molecules of both essential kinds (reproducing themselves and constructing a secondary molecule),. However, they could evolve greater power only if they were to go through reproductive cycles regularly, and whichever kind of proto-organism was driven through reproductive cycles by the cycle of night and day (or was more susceptible to that influence) would have led to all subsequent evolution. (And if there were several kinds, the one with the most powerful structural effects for controlling relevant conditions would have led to subsequent evolution.)

It is possible, therefore, to identify the original proto-organism, if this is how evolution began and has been caused on earth. That proto-organism would still be doing both kinds of work, reproductive and non-reproductive, in existing organisms, because they would be merely higher level of part-whole complexity in the coordination of such behavior. The simplest structures doing both kinds of work in living organisms are RNA molecules.

Thus, if we believe that the beginning of evolution must have been ontologically necessary, like so many other aspects of the world, we discover something that empirical biology does not recognize. RNA had a primitive way of synthesizing proteins at the very beginning, for unless it was able to do non-reproductive work of that kind, it could not have been the proto-organism with which evolution on earth began. Thus, we predict that RNA molecules will eventually be discovered to be a structural cause capable, in suitable, natural circumstances, of generating a structural global regularity in which amino acids are assembled as a protein molecule.

All that has been demonstrated, however, is that it is possible that this is how evolution began on earth and, thus, that it was inevitable. When I argue, therefore, that the course of evolution is inevitable, as I shall at each of the subsequent stages, it should be understood as an ontologically necessary truth that depends on RNA having a primitive way of synthesizing proteins as well as on the specific nature of matter and large scale structure of the actual world.

This ontological explanation of the inevitability of evolution by reproductive causation does not imply that evolution begins in every planetary system.

Unless the planetary system forms out of the debris of super nova explosions, they will not have the heavier atoms needed for many of the more complex molecules that are needed for there to be proto-organisms of this kind. (But since stars that explode as super novas are rather large, they form early after the Big Bang and have rather short life spans. Thus, there is likely to be a supply of heavy atoms where middle range stars like the sun form.)

It is also necessary that a large range of different kinds of molecules actually exist and interact in the various ways possible for them. That is not likely on the surfaces of some planets. Some are too hot (and supply too much energy) for such molecules to exist, and others are too cold (and do not supply enough energy).

Furthermore, it has long been recognized that the kind of planet on which conditions are most favorable for a wide variety of molecular interactions are those on which the temperature allows water to be liquid and there is enough water to provide a medium in which larger molecules can interact. (Water moderates the kinetic energy with which other molecules can interact and, thus, makes it more likely that they will not be destroyed by the ambient motion and interaction. Not only is water one of the simplest stable molecules, making it rather abundant, but the range of temperatures at which it is liquid is exceptionally wide.) Thus, we can be sure that at least one planet in many, if not most, planetary systems around stars like the sun include one that is favorable for such a wide variety of molecular interactions.

Nor is it easy to rule out the possibility of evolution occurring under substantially different conditions, such as orbits in systems with binary stars or planets with only water and no land. If evolution is possible in such situations, it might follow a somewhat different course.

The Gradual Evolution of RNA. We assume, therefore, that RNA molecules were the original proto-organisms. But the original RNA molecules must have been simple, with only a few varieties, and barely able to go through reproductive cycles at all. Reproductive causation would, however, make them more complex, more diverse and better able to control the conditions affecting their reproduction. The major accomplishment of this first stage of gradual evolution is a much more efficient and reliable way synthesizing protein molecule, which helps make the second stage possible. But at this first stage, when the proto-organisms are so simple, there is a way that reproductive causation works on them at two levels of part-whole complexity.

Natural selection at the individual level. At the level of individual RNA molecules, reproductive causation leads us to expect that every new power to control relevant conditions would evolve as it becomes possible, that is, as random variations on extant RNA synthesize proteins happen to control some new condition that affects reproduction or controls some old condition better.

Those RNA molecules whose proteins controlled some relevant condition, such as supplying nucleotides for reproduction, would be more likely to reproduce, because they would be more likely to be located where RNA were benefiting from them. There would be random variations on them, because RNA reproduction is far from perfect. Kinds of nucleotides would be substituted, new nucleotides would be added, and whole RNA could be spliced together. Such random variations on existing RNA would sometimes alter the kind of amino acid used at some point in the protein or add new amino acids, and if these slightly different proteins or slightly more complex proteins were any better able to control the relevant condition, the RNA molecule producing them would be located where it was somewhat more likely to benefit from them and, thus, would be more likely to succeed in reproduction.

Since the triplets of nucleotides are the structural causes bundled together as a proto-organism, the relevant condition that is controlled by the work each does is determining which amino acid is appended in the growing peptide chain at some point. Different triplets of nucleotides in the RNA would control different relevant conditions by determining amino acids at other points in the protein being synthesized. Thus, reproductive causation would make these proto-organisms gradually more powerful over their whole reproductive cycles by altering the bundle of structural causes — shaping each structural cause to be as effective as possible in determining some amino acid, adding new structural causes when the amino acid they add makes the chain more power, and fitting those structural causes together harmoniously as parts of a single RNA — so that the RNA molecule eventually has maximum power over the whole cycle. But maximum holistic power for an RNA molecule is just whatever power comes from the kind of protein it produces existing in the neighborhood.

Even if evolution began with a single variety of RNA whose protein did some useful work, evolutionary change would not stop at making its protein as powerful as possible, because some random variations on existing RNA would synthesize proteins that controlled other relevant conditions. If the first kind of protein supplied nucleotides for RNA synthesis, there are surely random variations on its RNA template whose slightly different protein molecules would supply other kinds of nucleotides, or supply the same kinds of nucleotides in from other sources. Again, random variations on existing RNA that happened to control some new condition affecting RNA reproduction would be more likely to succeed in reproducing, because their location in the region would make the more likely to benefit. Thus, from the original RNA molecule(s) would evolve a variety of RNA molecules serving as templates for proteins with different functions, and each would become maximally powerful in serving its function.

Natural selection at the group level. The increasing diversity of RNA molecules would make their combination in local regions an ecology, and the most spectacular accomplishments of the first stage of evolution, such as a more efficient and reliable process of synthesizing proteins, would come from the increasing power of the ecology as a whole.

Natural selection would not be very selective at first. Though RNA whose proteins controlled some relevant conditions would be more likely to reproduce because they would be in the right location to benefit from the protein, other nearby RNA would also tend to benefit. But once there were enough different kinds of RNA whose proteins making different contributions to the reproduction of them all, change in the direction of maximum holistic power at the ecological level would be accelerated by a weak form of reproductive causation at the level of local ecologies.

Different local ecologies would be like different higher level organisms trying out different combinations of RNA. Each local region would contain various kinds of RNA, synthesizing various kinds of proteins, and they would all be driven through cycles of reproduction by the cycle of night and day side by side in the water. The varieties of RNA would be like the many structural causes “bundled together” like a higher level organism, for the proteins synthesized by all of them would tend to jointly control conditions in their local region that affected the reproduction of them all. And such ecologies of RNA molecules would also be able to reproduce as a whole, like higher level organisms, because when storms or other major disturbances scattered molecules to new local regions, and RNA that wound up in favorable circumstances where they could have both structural effects would start new colonies. Colonies with the right combinations of varieties of RNA would generate proteins of different kinds whose joint control of conditions affecting the reproductive of them all would make their populations of RNA grow faster. Thus, when the next storm came along, the more powerful combinations of RNA molecules would tend to populate the favorable locations when more normal conditions resumed. Random variations in bundling RNA together would be introduced by the reproduction of such “higher level organisms,” because the varieties of RNA that would wind up together in any given local region would be a mixture of varieties of RNA from several local regions. Since there are only so many favorable locations for such colonies of RNA to be set up, their reproduction would eventually make free energy scarce, and a natural selection would be made by the greater reproductive success of some whole colonies.

The relative lack of selectivity about natural selection at the level of individual RNA molecules would, therefore, make possible a powerful form of group selection, which would make the combination of different varieties of RNA in each region as powerful as possible as a whole in controlling all the conditions that affect RNA reproduction generally. Since random variations at the level of these higher level “ecological organisms” are made possible by how they are made up of RNA molecules as parts, there are three ways in which random variations may make them more powerful as a whole.

The first kind of change that occurs at the higher level of part-whole complexity (the local regions where RNA exists side-by-side in space) is the gradual change in each variety of RNA that shapes its protein to perform its function as effectively as possible. This is the gradual change described at the outset of this description of the gradual evolution of RNA, which itself involves three kinds of change because each RNA molecules is a bundle of structural causes, with each triplet of nucleotide determining the amino acid for some location in its protein molecule. Random variations on the RNA molecule that synthesizes it would try out variations on the protein, and the more effective varieties would tend to be the ones that succeed in reproducing, because they would be located in the local region where the condition was controlled and so there would be more of them to be scattered to new regions when a storm or other disturbance occurred.

Second, new varieties of RNA would be added to the colony when random variations on existing RNA happen to synthesize a protein that controls some new condition that affects their reproduction (or some old condition in a new way). Not only would it tend to be selected within the colony by its greater likelihood of being located where the protein’s benefit was provided, but it would eventually be added to the mix in other local regions. To take an extreme example, suppose that it alleviated some bottleneck in the process affecting them all. That would make all the RNA in the local region would be more successful in reproducing, and there would be more RNA from that colony to scatter to new local regions when the next storm came.

Third, the useful proteins that were being synthesized would also be shaped to work together as harmoniously and efficiently as possible with other proteins in local regions, because the reproduction of all the RNA molecules in the neighborhood is the joint result of the proteins synthesized by all the RNA. Thus, as different combinations of RNA molecules were tried out in different regions, those combinations that worked together most harmoniously and even assisted one another would tend to succeed, while less harmonious combinations would fail, because there would be more of them to scatter to new regions when storms or other disturbances occurred.

Reproductive causation was still weak, but since it was operating on the level of whole ecologies of RNA as well as on each variety of RNA within a local region, there would be an increase in the power of whole colonies of RNA to control conditions that affect the reproduction of them all. Although RNA molecules start off simple, weak and uniform, their stage of gradual evolution would eventually make them complex, powerful and diverse. Indeed, this would happen to whole colonies of RNA, because insofar as there is a range of different favorable locations for them, different combinations of RNA would evolve to tap the free energy available in all of them. The surface of a planet surely makes it possible for RNA molecules to go through reproductive cycles on a sufficiently large scale to try out all the random variations on existing RNA that are possible, and thus, each new relevant condition that could be controlled would be brought under control as it became possible.

More efficient and reliable protein synthesis. It is not necessary to trace the whole course of the gradual evolution of RNA, but it is worth mentioning what is probably its most significant contribution to subsequent evolution, namely, an efficient and reliable way of synthesizing protein molecules.

The original process by which RNA molecules synthesized the proteins that brought the first relevant conditions under control (such as supplying energy-rich parts for RNA replication) was probably weak and inefficient. The power to control relevant conditions of all kinds would have been greatly increased, therefore, by random variations whose proteins made the synthesis of proteins more reliable or powerful. There are many ways it could have been improved, including changes that expanded the kinds of amino acids that could be used. The first improvements may have been proteins that helped line up amino acids with the RNA and a substratum so that the protein chain was more likely to form. Such changes could have had far reaching effects, because it could give a function to previously useless proteins that were relatively abundant because they were so simple that they were continually being tried out, eventually selecting the RNA molecules that synthesized them. But the nature of the primitive means of protein synthesis is obscure, and the reason could be that major changes occurred its early evolution.

One indication that the original way of having a structural effect in addition to reproduction involved the synthesis of amino acids is that the successive bases, which are the information-carrying face of nucleotides, can be held together in chains by amino acids as well as by the phosphates used in RNA (and DNA). Such chains of amino acids are called "peptides," the chain that carries these bases are called PNA (rtaher than RNA or DNA). It means that amino acids interact with the molecules by which nucleotides determine which kind of amino acid to attach next in a way that could have occurred without the elaborate molecular machinery now used.

An example of a major evolutionary change would be the addition or deletion of the kinds of nucleic acids used. Protein synthesis may originally have involved only two or three nucleic acids and others were added as special proteins evolved that enabled them to use new kinds of amino acids in the proteins being synthesized. Or it may originally have used kinds of nucleic acids that interact more readily with amino acids and they subsequently dropped out when proteins evolved that enabled fewer nucleic acids to determine the amino acid to be added. It may even be possible that the original code used only two nucleic acids to identify which of the amino acids then being used were to be added, and later, assisted by new proteins, it was replaced by the three-nucleotide code found in existing living objects. But whatever the major changes were that occurred early in its evolution, they not only made it possible for RNA molecules to do their work more reliably and efficiently, but probably also increased the variety of amino acids used in constructing proteins from the few kinds that were probably involved at first to the twenty or so kinds of amino acids found in living objects.

Only 20 or so kinds of amino acids are used in synthesizing proteins, but they were selected from the enormous variety of amino acids that was availabe at the time. What singled these amino acids out was presumably that they provided enough variety for sequences of them to serve as all the kinds of molecular machines needed to handle other molecules. There is probably a geometrical aspect to the amino acids used that enables them to be combined in all the basic ways required to construct complex structural causes, and when it is explained, the currently intractable problem of predicing the conformations of proteins from their amino-acid sequence will have largely been solved.

Though the addition of new proteins to assist the process of protein synthesis would make such major changes possible, they would, at the same time, make the link between the nucleotides and amino acids more indirect. That would explain how the primitive way of synthesizing proteins evolved into its current, complex form. Even in the simplest forms of life on earth, protein synthesis depends on the interaction of RNA molecules with a complex machine composed of as many as fifty-five different protein molecules and three RNA molecules. "Ribosomes", as they are called, assemble themselves automatically in water because of their geometrical structures and how weak forces located on them bind them together. And they can consume only amino acids that have been attached as parts of tRNA molecules. But little is known about how ribosomes works, and when it is worked lut, there may well be empirical proof that original way in which RNA structural effects for doing non-reproductive work was a direct interaction between RNA and amino acids that linked them together in short chains.

2. Prokaryotic stage: DNA molecules. What evolves at the second stage are DNA molecules, which are a higher level of biological organization than RNA molecules, and the major accomplishment of this stage is the living cell, currently represented by bacteria and other prokaryotic cells.

In general, a new stage of evolution is caused ontologically by a higher level of part-whole complexity in the organisms that have already evolved. But as we have seen, in order to be a higher level organism, the lower level organisms must be bundled together as structural causes in a way that coordinates their behavior both in doing the work of reproducing itself and in doing the non-reproductive work that controls conditions affecting its reproduction.

An evolutionary stage in which organisms with a higher level of part-whole complexity evolves gradually in the direction of natural perfection for organisms of its kind is inevitable, if it is both possible and functional (that is, the higher level of organization can be tried out as a random variation and it is able to control an entire range of conditions affecting reproduction that were out of reach during the previous stage).

The inevitability of DNA proto-organisms. In this case, the lower level organisms are simpler proto-organisms, the RNA molecules that evolved at the first stage of evolution, though as we have seen, different varieties of RNA were to some extent combined in favorable regions where they all shared the benefits of the useful proteins being synthesized by any of them. And the upper level organism that begins the second stage of evolution is itself merely a higher level proto-organism, at least initially, for it starts off as just a way of attaching RNA-like molecules to one another as parts of a bigger macromolecule: the DNA molecule. DNA proto-organisms can, therefore, be the ontological cause of another stage of evolution, and a second evolutionary stage is inevitable, because such a higher level of biological organization is both possible and increases the power to control relevant conditions.

The possibility of DNA. There is no special problem about showing how it was possible for the evolved organisms to try out the radical variation that would begin the second stage, because gradual evolution during the first stage had already coordinated the behavior of RNA molecules in doing both kinds of work and useful combinations of varieties of RNA were already combined in favorable locales.

The DNA molecule, like RNA molecules, is a strand of nucleic acids linked by a sugar-and-phosphate backbone, but the kind of sugar used in DNA enables complementary strands of its nucleic acids to bind together and wind up as a double helix, which is a more stable molecule than strands of RNA. There is no reason to doubt that the range of random variations on the process of RNA reproduction was wide enough to try out DNA molecules made up of copies of evolved RNA molecules.

The random variations included the substitution of a new kind of nucleotide substituted for one of the (four) kinds used in RNA and a new kind of sugar backbone for holding members of the new set of nucleotides together as a DNA molecule. The single strand of DNA could then become a double helix by synthesizing its own complement, that is, by each nucleotide attracting its complement and binding them together as a second stand of DNA.

In order to go through reproductive cycles, organisms must be able to generate both essential kinds of structural effects, reproduction and various forms of non-reproductive work. That was possible in this case, because the various structural causes bundled together in of DNA molecules were copies of lower level proto-organisms that were able to do both kinds of essential work at the previous stage.

The DNA molecule could do non-reproductive work, because it contains multiple parts, usually called "genes", each of which has a geometrical structure that can serve as a template from which the RNA molecule (called messenger-RNA, or mRNA) can be transcribed. And DNA molecules could synthesize proteins in the established way, because the ribosomes and tRNA needed for protein synthesis had already evolved and were readily available in colonies of RNA in every local region. To be sure, transcription is a structural effect that requires the help of special protein catalysts. But natural selection was so inefficient at the first stage that they would be among the proteins being synthesized in at least some colonies of RNA. And a template for such proteins would be among the first genes included in DNA molecules, since their expressions would control a condition that affects their reproduction.

DNA reproduction also requires a special protein to promote it, but such a protein could be supplied in a similar way at first. And with the addition of one kind of nucleotide to those available in such colonies, DNA molecules would have all the parts they need to reproduce themselves in much the same way as RNA..

At the beginning, DNA molecules would be able to reproduce and control conditions affecting their reproduction, because there were favorable conditions. Colonies of RNA would provide most of the energy, parts, ribosomes and other housekeeping molecules, and DNA molecules themselves could direct the synthesis of the new protein molecules needed to control the condition affecting their own reproduction.

That is, by containing a gene whose protein facilitated transcription of mRNA and another gene whose protein facilitated its own replication, DNA molecules would themselves enrich the mix of molecules in the region sufficiently to go through reproductive cycles alongside RNA in the same regions, reproducing themselves and doing non-reproductive work during the same period of the circadian cycle as RNA.

The second level of biological organization illustrates a feature typical of biological levels: not only is the organism going through reproductive cycles on a higher level of part-whole complexity in space than the organisms from the previous stage, but each reproductive cycle of the higher level organism usually involves many reproductive cycles of lower level organisms. That is, in the biological levels, the reproductive cycles at the next stage have a higher level of part-whole complexity in time as well as a higher level of part-whole complexity in space.

DNA molecules generate non-reproductive structural effects by transcribing segments as mRNA molecules and using the mRNA molecules to synthesize a protein molecule, and this process may occur many times from the same gene.

The greater power of DNA. Nor is it difficult to see why this higher level of part-whole complexity in evolving organisms would be able to control conditions affecting reproduction beyond what was possible at the previous stage. The favorable environment provided by the gradual evolution of RNA toward natural perfection for proto-organisms of their kind is what made it possible for DNA molecules to go through cycles in which their parts (genes) did the non-reproductive work of synthesizing protein and they reproduced themselves as a whole. And DNA would evolve by reproductive causation, because they were also driven through reproductive cycles by the cycle of night and day, along with RNA.

The main source of the greater power of DNA to control additional relevant conditions is their higher level of part-whole complexity. They have traits with a higher level of part-whole complexity. They could generate many non-reproductive structural effects by directing the synthesis of various proteins, and thus, they could bring conditions under control that required special combinations of proteins. Some of the powers they evolved are described below.

Moreover, their higher level traits would evolve faster than colonies of RNA, because useful combinations of proteins would be selected more reliably by the success of a DNA molecule in reproducing as a whole than they were at the first stage. (Combinations of proteins were selected at the first stage by the success of the several independent RNA templates for those proteins being more likely to populate favorable regions when storms came because of their greater population.)

For example, when storms redistributed both RNA and DNA molecules, not enough of the RNA molecules may arrive at the same locale for any of them to be of much use. But DNA molecules with a useful combination of genes could direct the synthesis of a number of unusual proteins at a single location, and both DNA and RNA would be able to complete reproductive cycles.

Furthermore, the range of random variations from which a natural selection was made was likewise greater, because in addition to new genes, DNA molecules could try out new combinations of established genes (especially if, among the kinds of proteins that had evolved by then for interacting with DNA, there were some that could cut DNA molecules and link them together in different ways).

It is inevitable, therefore, that proto-organisms with a higher level of biological organization would begin a second stage of evolution. We know from our ontological explanation that, if reproductive cycles generated by higher level organisms are both possible and more powerful, they are inevitable and another stage of evolution will inevitably begin. And since, as we have seen, DNA molecules satisfy those conditions, they would begin a second stage of gradual evolution.

There may be other ways of combining RNA molecules as parts of a higher level proto-organism which could also go through reproductive cycles. But our ontological explanation of evolution as a global regularity implies that the most powerful among them becomes the foundation of subsequent evolution, and thus, we know from the structures of extant organism that DNA molecules were the most powerful.

Gradual evolution of DNA. Without tracing its course in detail, we can sketch some of the more significant accomplishments of the gradual change of DNA molecules in the direction of maximum holistic power for proto-organisms of its kind, and that will put us in a position to explain the origin of life.

Regulatory mechanism. As we have seen, its higher level of biological organization enabled DNA to do non-reproductive work requiring the cooperation of multiple protein molecules. But that was only the first step in the increase of power that was possible for this higher level organism, because power could increase with better coordination of the behavior of the RNA-level proto-organisms.

There is some coordination in the synthesis of proteins in the fact that their templates, or genes, are all parts of the same DNA molecule. That would make DNA molecules more powerful than RNA molecules, even if it was a random process that selected which genes on the DNA to use in synthesizing proteins. But DNA molecules could evolve far more powerful ways of coordinating the behavior of the lower level organisms, for there are mechanisms that can make the synthesis of special sets of proteins depend on the conditions that prevailed in the local colonies of RNA they encountered.

The geometrical structure of DNA would make such a random variation possible. When complementary strands of DNA wind up and form a double helix, the genes they contain cannot do either essential kind of work. Thus, if the DNA molecule was normally kept closed during the phase of the cycle when its structural causes were doing non-reproductive work (except, perhaps, for a certain region of genes whose proteins facilitated mRNA transcription, DNA replication, or universal housekeeping functions), it could serve as a mechanism for coordinating the non-reproductive behavior of the lower level organisms of which it is composed. It required only the evolution of genes whose proteins would respond to molecules in the region indicating that a certain condition prevailed by opening up certain segments of DNA, allowing the genes located there to be transcribed into RNA for protein synthesis, and closing them up again when the conditions changed.

The evolution of proteins that promote, repress, or de-repress segments of DNA would also enable DNA to generate discriminative responses to situations, controlling only the conditions that needed to be controlled. DNA molecules with such a regulatory mechanism could succeed in reproducing, while DNA molecules without it failed, because they would control relevant conditions more efficiently, that is, doing more with less.

The evolution of such a regulatory mechanism would enable DNA to respond to each situation in which it found itself by coordinating the behavior of its parts to control the conditions that happened to be relevant there. But that did not exhaust the new powers that were possible with a regulatory mechanism, because it also became possible to give the behavior of lower level organisms a temporal structure.

Once DNA had evolved the power to synthesize different combinations of proteins in response to different situations, the selection of rather minor random variations would make it possible for a single DNA to act on the world in a way that involved a series such coordinated responses. Messenger molecules signaling that some condition had been brought under control by one behavior could be the trigger for initiating another kind of behavior to control the next. The ability to make one change in the environment and then another when the first was completed would bring new relevant conditions under control.

Non-reproductive structural effects with a temporal structure could evolve for controlling new relevant conditions even though other relevant conditions in the region were being controlled more or less jointly (with RNA and its "housekeeping" proteins playing a supportive role to a variety of DNA in the region). It would make a difference locally which would tend to affect the reproduction of the DNA that generated the behavior, because it would be located nearby. But it would also enable its colony to be selected over others at the level of the group when storms or other disturbance redistributed all the molecules.

The cell. The power of this DNA-based regulatory system to coordinate the behavior of its parts as a sequence of responses to changing conditions was not fully exploited, however, until the evolution of a cell wall which enclosed all the molecular interactions generated by a single DNA molecule and isolated them from the surrounding colony. The cell, perhaps, marks the point at which proto-organisms evolve into something must be called an organism. The cell wall made it possible for complex sequences of behavior to add up reliably over time to a definite local result.

Cell-wall barriers may have evolved from the protein-based mechanism whose function was to keep regulatory proteins attached to DNA molecules after reproducing, for the reproduction of the whole DNA-based regulatory mechanism involved not only copying the DNA molecule itself, but also supplying new regulatory proteins for the copy made. This is consistent with prokaryotes, in which the loop of DNA remains attached to the cell wall.

Whatever their original function, however, once barriers became a wall separating the regulatory mechanism and its structural effects on molecules from the rest of the world, DNA molecules would be able to do non-reproductive work by generating behavior that involved complex sequences of RNA-level responses. The change made by each step in such a sequence could build on the effect of the previous step, and thus, the behavior of the cell as a whole could control conditions that were out of reach for naked DNA molecules.

There was, of course, a price to be paid for adding a cell wall to the DNA-based regulatory system. The cells were part of the structure that had to be reproduced along with the DNA molecules in order to reproduce the whole higher level organism. Thus, DNA would have to generate non-reproductive behavior that would construct a new cell wall during one phase, and it would have to divide the cell as part of its reproductive behavior during the other phase. But these are precisely the kinds of conditions that could be controlled by DNA with the ability to generate various combinations of proteins in sequences over time with cumulative local effects.

To be sure, once it was enclosed in a cell, DNA could not rely on RNA in the region to supply the “housekeeping” proteins, but had to include the genes that supply them. By the same token, however, this assured the natural selection of such DNA, for they could overcome the recurrent scarcity of parts and energy in RNA colonies by tapping sources of free energy in territories that were uninhabitable by RNA.

The evolution of cell walls once again increased the efficiency of reproductive causation. When the organisms going through cycles of reproduction were simply proto-organisms depending on the molecules available in a local colony to use free energy to do work, like RNA molecules, they were selected for synthesizing functional proteins by being located where their reproduction was more likely to be affected by them and by being reproduced in such numbers that they were more likely to wind up in favorable, local regions after a storm. Though reproductive causation does not need any more than a weak connection between useful non-reproductive work and reproduction, its efficiency is increased when natural selection is more discriminating.

DNA took the first step toward coordinating the behavior of RNA molecules by tying the fates of various genes together as parts of a single molecule, but, without a cell, the control of relevant conditions was still a joint project in each region, with different kinds of DNA benefiting from one anothers secondary effects and RNA playing a supporting role to all the DNA molecules located there by supplying the "housekeeping" proteins.

But once there was a cell to contain all the proteins synthesized by a single DNA, all the conditions required to go through a reproductive cycle could be controlled by a single organism. This concentrated the global reproductive cycle into many local reproductive cycles, and the cell as a whole became gradually more powerful in controlling all the conditions that affected its reproduction. (See diagram of reproductive cycle of nonliving organism.)

A DNA-based regulatory mechanism contained by a cell is the kind of complex material structure whose reproductive cycles constitute, along with space, the basic reproductive global regularity. It can go through reproductive cycles as a whole, because it can do both kinds of essential work. It coordinates the behavior of its genes to do non-reproductive work by transcribing mRNA whose protein products control relevant conditions, such as acquiring energy and parts from the environment and constructing more cell wall. It also coordinates the behavior of its genes to do reproductive work by transcribing mRNA whose proteins prepare for DNA replication, cell division, and carry out the sequence of changes involved in reproducing. But there is one further step that would make such cells even more powerful in controlling relevant conditions.

The Biological Behavior Guidance System. Even with the evolution of a cell wall, organisms based on DNA are still driven through reproductive cycles by the cyclic change in the supply of free energy due to the rotation of the planet. But this simple organism would be more powerful, if it could go through reproductive cycles on its own, independently of the circadian cycle.

Such cells would be more powerful because they would be able to go through reproductive cycles faster than organisms still entrained by the cycle of night and day, thereby consuming the free energy and parts before others could. They could also tap energy sources in locations that were previously uninhabitable because they were not affected in the right way by the circadian cycle.

In order to complete reproductive cycles on its own, however, it needed a system for selecting which of the two essential kinds of behavior to generate at any moment and for generating it, because DNA cannot transcribe mRNA and replicate itself at the same time.

Such a system required only a relatively minor change. Since the DNA-based regulatory mechanism could already express different genes depending on the kinds of messenger molecules present at any moment, the presence of a messenger molecule indicating that the cell had gathered enough energy and grown large enough could trigger the switch to reproduction. And it could switch back to growth again when another kind of molecule, which was present only when reproduction was complete, opened up the growth-genes. But since the chemical interactions involved in doing both kinds of work evolved under the energy conditions imposed by the cycle of night and day, it may also have required other new protein mechanisms to adapt them to the new conditions. (For example, to synthesize proteins at night, it may have had to replace the free energy formerly provided by high energy photons).

Let us call this mechanism for coordinating behavior the "biological behavior guidance system." Though some of its functions have been served by DNA from the beginning, all the steps we have traced in its gradual change in the direction of greater power must be traversed before DNA has accumulated the additional material structures required to be the ontological cause of all the structural global regularities needed to go through a cycle of reproduction on its own (when the region contains free energy that it can tap and other resources, such as the parts it needs for doing both kinds of work).

A higher level of part-whole complexity in organisms going through reproductive cycles is what causes a new stage of gradual evolution, and that requires the higher level organism to have some way of coordinating the behavior of the lower level organisms. That was done implicitly by DNA from the beginning by combining many genes, the equivalent of RNA proto-organisms, as parts of a single complex molecule, and we have traced how reproductive causation gradually increased the complexity of the higher level proto-organism, adding regulatory proteins and a cell wall, so that the higher level organisms could, as a structural cause, generate more complex behavior as a whole. Finally, the behavior it generates as a whole comes to include selecting between growth and reproduction and generating each of them when selected. At that point in the second stage of evolution, it serves all the functions of a biological behavior guidance system.

Though behavior guidance is a form of non-reproductive work that controls reproduction, that does not erase the difference between reproductive and non-reproductive work. An organism is still a bundle of structural causes, and in addition to coordinating all their behavior, it must be able to reproduce its structure as a whole. Reproduction is still unique: it is the construction of a material object with a geometrical structure like itself. And reproductive work requires parts throughout the whole prokaryotic organism to move and interact with one another in a fundamentally different way from non-reproductive work. Besides copying its DNA molecule and synthesizing regulatory proteins for its offspring, it must divide its cell by dismantling it in some places and constructing new cell wall in a different way from simply growing. That requires the DNA molecule and its regulatory mechanism to move and interact in basically different ways from doing non-reproductive work. What is different when the biological behavior guidance system evolves is that selecting when to reproduce becomes one of the kinds of behavior generated as part of its non-reproductive work, that is, a structural global regularity involving the transcription of mRNA and synthesis of proteins. That means it must set up the conditions that will not only result in its reproduction, but also put the biological behavior guidance system back in a condition in which it can select and generate other kinds of behavior when it is done reproducing. Thus, when the non-reproductive work of the cell comes to include selecting between phases of growth and reproduction, that does not make reproduction a form of non-reproductive work, but merely controls when reproduction occurs.

With the evolution of a biological behavior guidance system in the DNA-containing cell, what exists are organism of the same kind as bacteria, which are called “prokaryotes” or “prokaryotic cells.”

The prokaryotic biological behavior guidance system is the locus of changes in subsequent evolution. Those evolutionary changes are all basically kinds of non-reproductive work, or behavior, which the prokaryotic cell uses to control additional conditions that affect its reproduction, and since the biological behavior guidance system is an aspect of the geometrical structure of the whole organism that can determine whether it grows or reproduces, relatively minor modifications in that structure can select among and generate additional kinds of behavior. It is based on the regulatory mechanism, whose function was to generate various kinds of complex structural effects, but when it becomes part of a biological behavior guidance system, as aspect of the structure of the whole prokaryotic cell has the function of selecting and generating all its behavior. Thus, the evolution of new kinds of behavior involve changes in the behavior guidance system.

The origin and nature of life.Having show how the cell-enclosed DNA-based regulatory system evolves into a full-fledged biological behavior guidance system, we have derived from spatiomaterialism a material structure of the kind that is ordinarily said to alive. No one doubts that prokaryotic cells, such a bacteria, are living organisms. That would mean that in a spatiomaterial world like ours, the evolution of life is inevitable. It is one of the powers that organisms acquire during the second stage of evolution.

Life does not begin, therefore, deep in the ocean where heat is vented from the center of the Earth. It cannot, because there is no cycle in the supply of free energy, like the circadian cycle near the surface. It only appears to be where life began, because that is the ecological niche to which prokaryotes adapted that has changed least since the origin of life, and so it contains some of the earliest models of prokaryotic cells (called "archebacteria").

It is worth noting, however, what this explanation of its origin implies about the nature of life, for it suggests that life has an essential nature. To say that life has an essence is to say that there is a real difference — not just in our minds, but in the nature of things — between living and non-living organisms. Our ordinary understanding of life can tell us where to look for the difference, but in order to be sure what the nature of life is, those intuitions must be confirmed by an ontological cause. Life is a product of reproductive causation, but there should be some moment between the lifeless molecules with which evolution begins and the complex living organisms to which it leads, when a change occurs that is so basic that we recognize it as what our intuitions were seeing only confusedly.

Our ordinary conception of the nature of life seems to be captured by the notion of autonomous activity, given that it occurs naturally, rather than as just an artifact designed by beings like us. By "activity", I mean, not just a disposition, or physical property of the kind mentioned in the last chapter, but rather a more complex kind of goal-directed behavior in which different kinds of dispositions are generated in concert and feedback from these consequences is used to bring about some kind of overall change. And by “autonomy,” I mean that different kinds of activities are determined, not merely as responses to conditions that arise, as if they were guided by feedback in attaining some further goal, but rather internally, by something that selects among them. These are the traits to which we would point in order to remove any doubts that more highly evolved organisms are alive, and if we survey the significant steps in gradual evolution toward greater power, the step at which life begins may stand out.

We called RNA molecules “proto-organisms,” because they are already complex material structures that can do both essential kinds of work. (Each nucleotide attracts its complement in reproducing itself, and each triplet attracts a certain kind of amino acid in the non-reproductive work of protein synthesis.) Though they are on a higher level of part-whole complexity than most ordinary molecules, those ways of doing work are just dispositions, that is, mere physical properties. They are hardly “activities,” and there is nothing “autonomous” about them, since they are entrained by the circadian cycle.

The DNA molecule’s higher level of part-whole complexity enables it to coordinate the behavior of many RNA-level proto-organisms in doing both kinds of work. But neither kind of structural effect involves goal-directed behavior. Though its behavior as a whole may involve the synthesis of various protein molecules, they do not use feedback from the consequences of previous behavior to generate the kind of behavior that brings about some goal. It is still not activity in the relevant sense.

With the evolution of a regulatory mechanism, however, the DNA's higher level of organization does make the use of feedback possible. DNA can respond to different situations in different ways, and thus, the whole complex surely coordinate the behavior of many RNA-level organisms in one way in response to the consequences of coordinating the behavior of other RNA-level organisms in some other way. Though the use of feedback to attain the same goal in different ways in different situations makes it goal-directed, it is not yet enclosed in a cell wall, and so it is still just a series of responses that is largely controlled by the environment. Its activity lacks autonomy.

Enclosing the DNA-based regulatory mechanism within a cell makes its goal-directed behavior more autonomous, because it is able to coordinate the behavior of many lower level proto-organisms as a sequence of responses within its cell, each of which may depend on feedback from the last, and thereby carry out a temporally complex activity. That is what justified calling it an “organism,” rather than a mere “proto-organism.” But its activity is not fully autonomous, because its goals are given. Though such behavior may pursue different goals in different situations, the cell is not fully autonomous as long as its goal depends on the situation. Since its goals are still just variable means to a more encompassing, constant goal, the cell does not seem to alive. It is arguably just reacting to changes in its environment in ways that attain some overall goal, which is not itself chosen.

This final objection is overcome, however, when the cell-enclosed DNA-based regulatory mechanism evolves into a biological behavior guidance system, because at that point, its goals are not all dictated by changes in the environment. What determines when to grow and when to reproduce is no longer the circadian cycle, but the cell itself. It selects which goal to pursue for itself, depending on its own condition, mainly whether it has grown sufficiently large. Growth and reproduction are both goal-directed activities, but they are not simply sub-goals pursued as means to some constant overall goal. They are the two basically different kinds of work that an organism must do in order to evolve by reproductive causation.

Reproduction is not the goal of non-reproductive work, as we have seen, but rather the cause of evolutionary change. What changes is mainly the non-reproductive work. The organism acquires ways of behaving that make it increasingly powerful at controlling conditions that affect its reproduction, and the control of such a condition is the goal of every non-reproductive structural effect. What makes non-reproductive work functional is contributing to the holistic power of the organism. Thus, its function is not reproduction. Though reproduction may be a goal-directed activity, it is merely the kind of activity that causes population growth, scarcity and natural selection and does not itself have a function.

Furthermore, the power to choose between growth and reproduction on its own is, as we have seen, a form of non-reproductive work. It is another condition that is controlled by its behavior as a whole, that is, by coordinating the behavior the organisms of which it is composed. The cell-enclosed DNA-based regulatory mechanism opens up special segments of its DNA for transcription into mRNA and translation into proteins, while closing other, in order to set up the process by which it reproduces. That is the original function of the biological behavior guidance system.

The reason for calling this mechanism a “behavior guidance system” is that its function is not merely that of a mere cybernetic system, which uses feedback to adjust behavior in order attain some constant goal, but selecting between incompatible kinds of behavior. In the case of the biological behavior guidance system, it is selecting between phases of growth and reproduction, which cannot be generated at the same time. (There is, as we shall see, an additional kind of choice between goals that must be made in animals, and thus, the mechanism that serves that function will be called the “animal behavior guidance system.”) The function of selecting between incompatible kinds of behavior requires the behavior guidance system to have a structure that also serves to two other functions: input and output. It must have input from appropriate conditions in the world (including conditions in the organism itself) in order to select the right kind of behavior, and it must be able to generate one or another kind of behavior as output. In all, therefore, three functions are involved in behavior guidance, one involving choice, another involving input for making that choice, and a third for generating the behavior chosen as output. It is the output of a behavior guidance system that corresponds to a cybernetic system, because generating behavior often involves the use of feedback to guide it toward the goal that has been chosen. Although feedback also requires a kind of input, it does not necessarily use the same input mechanisms as the those that serve the function of choosing, for these input have different functions.

Judging by what is ordinarily meant by “life,” therefore, life begins when reproductive causation produces organisms with a biological behavior guidance system, for at that point, they can decide for themselves when to switch from pursuing one of at least two incompatible goal-directed activities. Though choosing between these goals still depends on input indicating when it has grown large enough or when reproduction is complete, it is autonomous in the sense that it is no longer merely responding to its environment as an external master. These cells are able to go through cycles of reproduction on their own, independently of the cycle of night and day. Life begins, therefore, when reproductive causation makes organisms powerful enough to remove themselves from the natural mold supplied by the large scale structure of the universe, the circadian cycle, and go through reproductive cycles on their own. Life begins with the autonomy of selecting between the two basic activities involved in reproductive cycles.

This concept of the essence of life implies that viruses and plasmids are not alive. They do not have a way of selecting between their two kinds of mechanical effects, but rather depend on living objects around them for their reproduction, just as primary structures did before the evolution of life.

This intuition about the essential nature of life is confirmed by its ontological significance, for the autonomy of the cell's activity marks a dramatic change in the ontological cause of evolution. We called organisms going through reproductive cycles the ontological cause of gradual evolutionary change, because given the wholeness of space, their motion and interaction had to add up over time to a global regularity in which their non-reproductive work becomes increasingly powerful at controlling relevant conditions. But such reproductive cycles are just a derivative ontological cause, since they are constituted by more basic ontological causes. And until the evolution of the biological behavior guidance system, the ontological causes constituting reproductive cycles were of two radically different kinds: the organism itself as structural cause generating both kinds of work and the large scale structure of the universe. The latter supplied not only the free energy required for the structural cause to do work, but also the temporal structure of the reproductive cycle, the cycle of night and day. However, there was a radical change in the ontological cause of evolutionary change when life evolved. Reproductive cycles become the autonomous activity of material structures. That is, the structural cause took over responsibility for the temporal structure of the reproductive cycle, leaving the large scale structure of the universe merely the role of supplying the free energy to be consumed in doing work. Thus, except for how reproductive cycles still depend on a supply of free energy, the beginning of life meant that the ultimate ontological cause from which the ontological cause of evolution derives is a complex material structure.

This dramatic change in the ontological cause of evolution means that, from this point on, evolution is something that organisms do to themselves. What causes natural selection, according to reproductive causation, is reproduction itself, because the multiplication of organisms in the region causes scarcity. As long as proto-organisms or organisms were driven through cycles of reproduction by the cycle of night and day, natural selection could be seen as something that was being done to them. But when the biological behavior guidance system evolved, structural causes not only do both essential kinds of work, but also generate the temporal structure of the cycle as a whole. Thus, evolution becomes something that living organisms do to themselves. Evolution still depends, of course, on the free energy supplied by its star. But given such a thermodynamic flow of matter from potential energy through kinetic energy and photons toward evenly distributed, life itself is what makes life evolve. That seems to be ontological confirmation enough of our intuition that life is essentially the kind autonomous activity that begins with the evolution of the biological behavior guidance system.

3. Eukaryotic stage: the nucleus.We have seen how the first two stages of evolution are caused by the first two levels of part-whole complexity in the organisms going through reproductive cycles, RNA molecules and those based on a single (looped) strand of DNA. And we have seen why those stages are inevitable. We identified the third stage of evolution when we were considering the levels of part-whole complexity in organisms on earth that might serve as ontological causes of evolutionary stage (in Change: Global: Revolutionary: Cause), because there are cells that are far more complex than prokaryotes, namely, eukaryotes, or cells with a “true nucleus.” They exists as independent organisms, but since they are basically the kind of cells that make up multicellular organisms on the fourth level of biological organization, they are an essential stage in the evolution of animals like us. In this case, however, it is not so obvious that the eukaryotic stage is caused by a higher level of biological organization.

Eukaryotes do not have the kind of structure we might expect on the model of the previous stage. Prokaryotic cells are not merely bundled together as parts of a larger structure, like RNA-level genes contained side by side in a DNA molecule — or for that matter, like cells in a multicellular organism. We have seen how it is plausible, nevertheless, to hold that eukaryotic cells have prokaryote-like parts. But the eukaryotic-level structure of which they are parts is so obviously functional that explaining its origin is problematic. It does not seem possible that the eukaryotic cell could have originated as a radical random variation on prokaryotic cells, and thus, the third stage does not seem inevitable.

Inevitability of eukaryotes. In order to derive another stage of evolution, given our ontological explanation of stages as a reproductive global regularity, we must show that a higher level of part-whole complexity in evolving structures is not only functional (in the sense of affording greater power to control relevant conditions), but also possible (in the sense that it can be tried out as a random variation on the organism that have been evolving at the current stage). In this case, the functional structure of eukaryotes makes it easy to see that they are more powerful than prokaryotes and can evolve an entire range of new powers that are out of reach for prokaryotes. But that same structure makes it difficult to see how they would ever be tried out as a random variation on prokaryotes even toward the end of their gradual evolution in the direction of natural perfection.

There is, however, an explanation of their origin that shows the eukaryotic stage to be inevitable. It has to do with how the higher level of organization that starts a new stage of evolution is not just bundling lower level organisms together, but also a way of coordinating the behavior those many lower level organisms. That is clearly what the nucleus of the eukaryotic cell is doing, and as we shall see, that function explains its origin. But before taking up the question about its possibility, let us be clear about the way in which organisms at the eukaryotic level of biological organization are inherently more powerful.

Greater power of eukaryotes. What distinguishes eukaryotes from prokaryotes is their nucleus, after which they are named. The nucleus is one indication of its higher level of biological organization, and by comparing the nucleus with the prokaryotic biological behavior guidance system, we can see how it is a new kind of biological behavior guidance system that makes eukaryotes far more powerful than prokaryotes.

Prokaryotic Cells.In the prokaryote, as we have seen, the biological behavior guidance system is a loop of DNA that is attached to the side of the cell wall that coordinates the behavior of RNA-level parts.

The cell’s behavior is generated ultimately by the synthesis of proteins, and behavior guidance is a structural global regularity caused ontologically by the structure of the prokaryote as a whole. Certain kinds of genes are selected for expression at any moment because of how the interaction of certain proteins with the DNA loop promotes the transcription of mRNA from certain segments of DNA, represses transcription from others, or de-represses transcription. When mRNA are translated into proteins (with the help of ribosomes), proteins interact with other molecules within the cell, and thus, the cell as a whole behaves. Behavior can depend on the situation, because the proteins triggering the expression of certain genes can be “messenger molecules” which are present only when certain conditions hold.

The same structural cause is responsible for the whole cycle of reproduction. The selection of certain segments of DNA for expression as proteins leads to the growth of the cell (including the acquisition of energy and parts, the construction of new cell wall and other non-reproductive work), and the selection of other segments of DNA reproduces the cell as a whole. After preparing the protein molecules required, the loop of DNA is replicated, the cell is divided, and one copy is enclosed in each new cell.

Thus, the prokaryote is lead through its cycle of reproduction by a simple, ratchet-like process that exposes certain segments of DNA and covers up others in lockstep with proteins that signal the success of each kind of behavior in the sequence, including growth and reproduction, at a minimum.

Eukaryotic Cells.The most obvious difference between eukaryotes and prokaryotes is the presences of a nucleus within the eukaryotic cell. The nucleus is one indication of the eukaryotes higher level of biological organization, as we have seen, it contains multiple chromosomes, each of which is roughly equivalent to one (or more) of the prokaryote’s loops of DNA. Each chromosome is also a DNA molecule containing many genes, but it is not a loop, it is much longer, and it is “complexed” with proteins.

That is, the parts of each chromosome are held together by a scaffold, and they can be drawn together in a tight, condensed form in order to be pulled around during reproduction. Normally, the strand is periodically wrapped around small proteins, like beads on a string, preventing transcription into mRNA.

Because the eukaryote has multiple chromosomes, it needs a nucleus to coordinate the expression of genes on different chromosomes at once. Since that it to coordinate the behavior of the lower level organisms bundled together in this higher level organism, the nucleus serves as its biological behavior guidance system. The nucleus selects and generates both essential kinds of behavior: growth (including various kinds of non-reproductive work) and reproduction (the construction of another object like itself).

The eukaryotes behavior is also generated ultimately by the synthesis of proteins. During periods of growth, the nucleus receives input from other parts of the cell (and the situation outside the cell) by messenger molecules transported into it. An interaction between those proteins and the chromosomes exposes certain segments of DNA on various chromosomes for transcription into mRNA, thereby selecting a kind of behavior for each situation. Behavior is generated as mRNA flows outward from the nucleus to the outer cell, where it is used to synthesize proteins (with the help of ribosomes). The flow of molecules is channeled throughout the cytoplasm by complex plasma membranes (the endoplasmic reticulum), and as protein machines interact in the outer cell, they generate the behavior of the cell as a whole.

Reproduction is an enormously complex process in which the chromosomes are replicated, the nucleus is dismantled, centrosomes form a spindle that divides the chromosomes, two new nucleuses are constructed, one for each copy, and the cell as a whole divides.

Though the behavior of the eukaryotic cell, like any machine, ultimately depends on its whole structure, its structure as a whole is such that its behavior is guided by only part of it, the nucleus, its behavior guidance system.

With the ability to express genes on multiple chromosomes at the same time, eukaryotes are able to coordinate the behavior of many prokaryote-level organisms, and thus, they are able to control conditions that are out of reach for solitary prokaryotes. That is, the source of greater power, as for all levels of biological organization, is the higher level of part-whole complexity itself. Size is a source of power in a world of space and matter.

Possibility of eukaryotes. In order to prove the inevitability of a new stage of gradual evolution, according to our ontological explanation of evolution, it is necessary to show both its possibility as well as its inherently greater power. Though the greater power is obvious, its possibility is problematic. It is not easy to see how its higher level of part-whole complexity could be tried out as a variation that somehow occur during the previous stage at the lower level approached maximum holistic power for organisms of their kind. The way that lower level organisms are bundled together in the eukaryotic cell is so highly organized and functional that it could not possibly have begun as just a random variation that happened to occur one day in the motion and interaction of prokaryotes and other molecules. Such an accident would be as incredible as supposing that life itself began as a random variation in molecules moving and interacting at random on the surface of a planet.

On the other hand, there is good reason to believe that prokaryotes played an important role in the evolution of eukaryotes, because there is another indication, besides a nucleus with its multiple chromosomes, of the eukaryote’s higher level of biological organization. It is the presence of mitochondria (in animals) or mitochondria and chloroplasts (in plants) in the cytoplasm outside the nucleus. These organelles are like organisms at the prokaryotic level of biological organization, because they contain their own DNA and reproduce themselves in the cytoplasm. Indeed, it is widely assumed that they are descendents of prokaryotes that existed about the time eukaryotes evolved. But their role in eukaryote evolution is unclear, because of the functional way that these lower level organisms are “bundled together” in the higher level organism. Though the behavior of these organelles is also coordinated by the nucleus, they are combined in the cytoplasm with a rich variety of other organelles that are constructed from molecules (and torn down) as part of the eukaryotic level behavior generated by the nucleus. What is needed is an explanation of the origin of those other structures in the eukaryote.

Received explanations of the origin of eukaryotes. Current speculation about the origin of eukaryotes is not very helpful in showing the inevitability of eukaryotes.

For example, it is not likely that one kind of prokaryote enslaved others, because prokaryotes are so equal in their abilities. And it does not explain the origin of the nucleus in any case, for it is very unlike a prokaryote.

Others suggest that the nucleus was originally an entirely different form of life that enslaved prokaryotes to exploit them for energy. But in order to explain the origin of the nucleus, there must have been a second origin of life entirely independent of prokaryotes. And if it needs prokaryotes as a source of energy, it does not explain where the nucleus obtained the energy that enabled it to enslave the prokaryotes -- or why it would bother, if it already had a source of energy. In any case, there is no trace of any such independent kind of living objects.

Lynn Margulis, a professor botany at the University of Massachusetts at Amherst, has proposed other possibilities, in which eukaryotes began as prokaryotes in which chloroplasts and mitochondria were invaders that were transformed into slaves. But like the predator hypothesis, it does not explain where the nucleus came from or how such an energy-consuming mechanism could evolve without prokaryotes to perform its energy functions.

Metabolic clue to the origin of eukaryotes. The clue that points the way to an explanation of their origin is, however, the energy function of chloroplasts and mitochondria in eukaryotes, at least, when we assume that stages of biological evolution are caused ontologically by organisms at one stage becoming organized as multiple parts of higher level organisms that go through reproductive cycles as a whole. That suggests that the eukaryotic structure was tried out, not on the model of enslavement or warfare, but on the model of cooperation. It could have been a result of change at the ecological level in the direction of maximum holistic power and a form of group level natural selection, as in the case of RNA evolution.

The function of the prokaryote-like organelles in eukaryotes is to acquire and process energy. Chloroplasts are organelles that trap the energy of photons in energy-rich molecules, and mitochondria are organelles that use oxygen to dismantle energy-rich molecules all the way down to water and carbon dioxide. Though they lack rigid cell walls, these organelles appear to be descendants of prokaryotes because they contain their own DNA and reproduce by binary fission in the cytoplasm of the eukaryotic cell. (Since chloroplasts contain chlorophyll a and b, whereas blue-green algae have only chlorophyll a, chloroplasts probably derive from the ancestors of Prochlorphyta, a recently discovered kind of prokaryote that contains both chlorophyll a and b.)

These organelles are the basis for classifying single-celled eukaryotes, or “protists,” into three basically different groups. Plant-like, animal-like, and fungus-like – are simply the three ways of exploiting the three prokaryotic methods of acquiring and processing energy.

Plant-like protists, which contain both kinds of organelles, are autotrophs, because (with chloroplasts to absorb energy from the sun and store it in energy-rich molecules and with mitochondria using “respiration” to turn those energy-rich molecules into free energy that can be used by molecular processes in the cell) they need only simple inorganic molecules, which are available everywhere, to complete their cycles of reproduction.

Animal-like protists, which contain only mitochondria, are heterotrophs, because they obtain energy-rich molecules from the environment to fuel behavior by incorporating other living objects as parts of themselves.

Heterotrophs that lack both kinds of prokaryote-like organelle are fungus-like protists, such as yeast, which use fermentation, the first way that prokaryotes found to process energy, to fuel behavior. (Fermentation releases only a fraction of the energy that respiration could extract from the energy-rich molecules, and thus, they are much less active than animal-like protists.)

What the ontological explanation of stages of evolution suggests is that the energy function of chloroplasts and mitochondria were coordinated in some way long before eukaryotes evolved, so that the nucleus was tried out as a variation on the natural perfection of certain ecologies of prokaryotes.

What I will describe here is speculative, and it is probably mistaken in some details. But such errors are not crippling in this case, because it still shows that it was possible for the evolution of prokaryotes to lead to a variation that made the eukaryotic level of biological organization inevitable. It is something like a “second origin of life,” but it is just as inevitable as the first origin of life.

There may be simpler ways in which the eukaryote level structure could be tried out by random variations, but they would also show the inevitability of the third stage. And as long as there are no such possibilities, this one can serve as a model for discovering the details about how it did happen.

The origin of eukaryotes.Traces of prokaryotes apparently date back about 3.5 billion years, within a billion years after the formation of the Earth. But since there are no traces of eukaryotes until about 1.4 billion years ago, prokaryotes probably had been evolving for about two billion years before eukaryotes showed up. Eukaryotic cells and multicellular organisms both evolved well before the Cambrian era, some 0.6 or 0.7 billion years ago, when the detailed fossil record begins. Empirical evidence leaves us in the dark, therefore, about how eukaryotes originated. But with the help of what we know ontologically about evolution, it is possible to see how it is would have been inevitable that eukaryotes evolved.

Aquatic balloons. Eukaryotes must have evolved after prokaryotes had discovered all three basic energy strategies and filled all the ecological niches that were possible for them in the habitable space near the surface of Earth. Fossils that date back 1.4 billion years suggest that the first eukaryotes were plant-like protists that floated near the surface of the ocean. This suggest that eukaryotes evolved when photosynthesizing prokaryotes happened on the trick of constructing a plasma membrane to contain them, thereby floating themselves together near the surface. The molecules making up plasma membranes form themselves into spheres in water that are relatively impermeable to larger molecules.

The plasma membrane is made of phospholipid molecules (simple sugars with a pair of long hydrocarbon tails on one side and an organic molecule attached to phosphate on the other). When phospholipids are lined up side by side, like matches, forming a two-dimensional sheet, there are weak bonds among them (Van der Waals forces, which come from synchronizing the electric forces exerted within each molecule), but since such bonds hold on all four sides of each tail, they are strong enough to preserve the configuration. Furthermore, the phosphate ends of the molecules have residual electric charges that attract water molecules (which also carry such residual charges), whereas the lipid ends of the molecule lacks any residual electric charge and thus do not attract water molecules. In a watery medium, as a result, water molecules tend to gather on the hydrophilic sides of the sheets that they form, thereby pushing the hydrophobic sides of the sheets together and forming a membrane of two layers. When enough phospholipids are present in the water, these bi-layered membranes naturally form themselves into the surface of a sphere, for that is their configuration of least energy: The membrane close holes that are made in it, giving up energy as bonds form among their hydrocarbon tails. The molecules can move past one another rather freely in the plane of the membrane, and thus, it is actually a two-dimensional liquid. But in order to preserve the integrity of the cell, their configuration as a closed surface in space must continue over the whole cycle of reproduction.

The proteins needed to construct plasma membranes had already evolved, since they are used to line the rigid walls of prokaryotic cells. But with rigid walls, prokaryotes are denser than water and normally sink to the bottom. They could inhabit only limited regions near the shores of the ocean. But prokaryotes would be able to float nearer the surface where they could absorb energy more easily, if they exported the proteins for managing their plasma membranes and used them to construct a large membrane. By including molecules of the right kinds within the membrane, the whole would be less dense than water, and it would open up a new habitat from which they could acquire energy to complete their cycles of reproduction.

Aquatic balloons would be, therefore, a result of the gradual evolution in the direction of natural perfection for ecologies of prokaryotes. The energy they needed was scarce near the bottom on the water, and since prokaryotes whose random variations contributed in some way to this joint control of that relevant condition would more likely be the right location to benefit from it, it would be a group-level natural selection of colonies of prokaryotes by the greater reproductive success.

The group level selection of entire ecologies also occurred, as we have seen, in the evolution of RNA. Combinations of RNA in favorable local regions were selected when storms or other disturbances came, because there would be more RNA molecules of their kinds to populate the new favorable locations. But group level selection occurs in prokaryotes because of how they cooperate in the construction of aquatic balloons in order to tap a new source of free energy.

At first, these aquatic balloons may simply have crashed when their residents had divided too many times and they grew too large. Then, new membranes would have to be constructed, and the scale of the task would require the cooperation of many prokaryotes. But this would have been possible only if their efforts were coordinated in a natural way, for example, by the rise of the sun and the increase in temperature.

Before long, however, some groups would have happened on the trick of dividing their membrane, instead of constructing a new one each morning, and could thereby stay afloat. Again, the scale of the task would require the cooperation of the many prokaryotes in each aquatic balloon, and the problem of coordination could be solved only by a regular, natural change, such as sunset and the fall in temperature. The reproductive cycles of these aquatic balloons were probably entrained, therefore, with the cycle of night and day. Once again, the circadian cycle was the mold for a reproductive cycle that only later evolved its own behavior guidance system.

Aquatic balloons would be, therefore, complex material structures with both kinds of behavior required to go through reproductive cycles, making them subject to reproductive causation. The aquatic balloons would multiply to fill the space in which reproductive cycles of this kind could be completed at all, and the resulting scarcity would impose natural selection on them. Though this would be group level natural selection relative to the prokaryotes involved, aquatic balloons would be organisms on the third level of biological organization, and as variations on the combinations of prokaryotes that made them better able to manage their membrane and coordinate their behavior completed reproductive cycles while others failed, they would become increasingly powerful in their new ecological niche. But they would not be living organisms on that biological level until they evolved a biological behavior guidance system of their own.

The nucleus. The nucleus would evolve as an improved means of coordinating their behavior. Instead of exporting the proteins from member prokaryotes, prokaryotes could have exported copies of the segments of their DNA, or genes, for handling the plasma membrane and housed them in a special membrane-enclosed chamber inside the outer membrane. It would be transformed by the gradual evolution of aquatic balloon into a nucleus that would serve as its biological behavior guidance system.

Proteins from the prokaryote’s DNA-based regulatory mechanism for selecting which segments of DNA to transcribe as mRNA could be adapted to handle strands of DNA in the nucleus. In order to synthesize proteins from these strands of DNA, however, genes for transcribing mRNA, ribosomes, and tRNA would also have to be donated to the nucleus by the prokaryotes -- as well genes for proteins that assist in replicating DNA. Since genes for proteins that divide the outer membrane would already have evolved, only minor modifications would have been required to manage a nuclear membrane as well as the outer membrane and to control the division of both so that each half of the outer membrane received one half of the divided nucleus. At first, the nucleus just assisted in managing the outer membrane, because the reproductive cycle was imposed by the cycle of night and day. But once the nucleus evolved mechanisms that enabled it to lead the whole through its cycle of reproduction, eventually even telling prokaryotic members when to divide, it would be a behavior guidance system that works on a new level of natural organization. Thus, reproductive causation once again free a new form of life from its natural mold.

Mitochondria and chloroplasts have a slightly different genetic code (that is, triplets of nucleotides determine slightly different amino acids in protein synthesis), and that might be expected on this explanation of the origin of the nucleus. Since the nucleus is a new kind of biological behavior guidance system which evolves from the cooperation of prokaryotes, it would not be surprising if rather fundamental changes occurred in the process.

Though chromosomes are on roughly the same level of natural organization as prokaryotes, it is not surprising they are much more complex than the prokaryote's loops of DNA. We should expect the nucleus to involve a complex process of molecular interactions for handling chromosomes, if the nucleus evolved from the cycle of night and day driving the cooperation of many prokaryotes through reproductive cycles. Since the nucleus was not responsible for leading the whole organism through its cycles of reproduction at first, it could start off simple and slowly acquire the complex machinery that would eventually enable it to take charge. The molecular machinery built into the cytoplasm and nucleus could be come quite elaborate, as during reproduction, when the nucleus closes up the chromosomes (in condensed form), connects them to other special molecules (and later disconnect them), moves them around in the cell, opens them up again so that its structure may flow from certain segments to protein synthesis, and much more.

Indeed, the new mechanisms of reproduction in the nucleus would be the foundation for much greater power, because the nucleus could use the condensation of chromosomes to help control which segments are exposed for transcription into mRNA during period of growth by opening up only certain parts of them. In any case, once the nucleus had taken over the function of a behavior guidance system, eukaryotes would be capable of a scale and variety of behavior that greatly exceeds prokaryotes or anything that multi-prokaryotic organisms could do. It would enable eukaryotes to establish cycles of reproduction in a much wider variety of ecological niches than prokaryotes.

This origin of the nucleus might also explain another peculiar difference between prokaryotes and eukaryotes. In eukaryotes, proteins are often synthesized from genes that are split up in several pieces of DNA separated by apparently meaningless stretches of DNA called "introns." The RNA transcribed from these meaningless segments are cut out and the meaningful segments pieced together before the mRNA are translated into proteins. This may be a new mechanism for controlling the synthesis of proteins, perhaps for synchronizing the synthesis of several different proteins.

Second origin of life. Unlike the enslavement model, this explanation of the origin of eukaryotes depends only on prokaryotes and kinds of behavior that are within their range. Living eukaryotic cells evolve from them in much the same way as living prokaryotes evolved from RNA molecules.

The key is how natural perfection at the ecological level becomes a form of group level natural selection because of how certain ecologies of prokaryotes happen on a way of taping a new source of free energy, controlling what is the most important condition affecting reproduction. The photosynthesizing prokaryotes that became chloroplasts in eukaryotic cells must have been involved in aquatic balloons from the beginning. The bacteria that became mitochondria in eukaryotes were probably also members of aquatic balloons from the outset, living in symbiosis with chloroplasts as part of the ecologies in which it happened. When they became organelles in the eukaryotes cytoplasm, both kinds of prokaryotes gave up their rigid cell walls in favor of plasma membranes.

However, if mitochondria were not members of the colony from the beginning, their presence in eukaryotic cells is not problematic, because evolving the ability to invade aquatic balloons later on to feed on the abundant supply of energy-rich molecules would have enslaved them in order to dismantle energy-rich molecules produced by chloroplasts into energy-rich molecules of a more usable kind.

The explanation of the origin of eukaryotes does, however, involves a "second origin of life" in a sense, because, once again, the cycle of reproduction was originally imposed by the cycle of night and day.

What made the origin of life inevitable was the cycle of night and day, for it drove RNA proto-organisms through reproductive cycles long enough to evolve, by way of DNA, into prokaryotes.

What made the evolution of eukaryotes inevitable was also the cycle of night and day, for it drove groups of prokaryotes, whose reproductive cycles were independent of the circadian cycle, through cycles in which a higher level organism, the aquatic balloon, was reproduced.

Furthermore, in both cases, what evolved was a higher level organism.

What evolved in one case was the DNA molecule, its regulatory mechanism, a cell and, finally, the first biological behavior guidance system able to go through reproductive cycles independent of the circadian cycle.

What evolved in the other case was the aquatic balloon, the nucleus with chromosomes, and, finally, the second biological behavior guidance system that was able to go through reproductive cycles independent of the circadian cycle.

This shows that the origin of eukaryotes was inevitable, for the only way that eukaryotic cells could fail to evolve in this way in a spatiomaterial world like ours is if there is some simpler way in which the structure of eukaryotic cells could be tried out as a variation that occurs during the gradual evolution of prokaryotes. If not, it would eventually occur as described here on any planet where life can get started at all, and thus, the eukaryotic stage of biological evolution will occur throughout the universe.

Gradual evolution.The evolution of the nucleus was the beginning of a new stage of gradual evolution in which eukaryotes change gradually in the direction of natural perfection for organisms of their kind. Ironically, the main accomplishment of that stage was the evolution of a way of incorporating the evolution of lower level structures within the eukaryotic cell. That innovation was sexual reproduction, which increased the power of reproductive causation and accelerated the pace of evolutionary change.

We have already encountered other increases in the speed of evolutionary change in tracing the overall course of evolution.

The natural selection of colonies of RNA for their combinations of kinds of RNA molecules was relatively weak at the first stage of evolution, because it depended on them having greater populations and, thus, being more likely to populate new colonies after a storm or other disturbance. But functional combinations of RNA level organisms could be naturally selected more reliably when they became genes included as segments of DNA molecules, because as DNA molecules, the combinations were more stable, and they could be tried out in a wider variety of locations.

Natural selection of RNA and DNA within colonies of molecules in favorable locations during the first and second stages was relatively weak, because the greater success of more functional RNA or DNA molecules came from being located in the colony where the proteins they synthesized had their effects. But natural selection of DNA molecules became more discriminating when they were enclosed in cells, because the fate of each DNA depended mainly on the non-reproductive structural effects that its own segments generated (rather than on the proteins synthesized by other DNA in the region).

In yet another way, even the evolution of the first biological behavior guidance system accelerated the pace of evolution, because the ability of prokaryotes to go through reproductive cycles more quickly than the circadian cycle meant that there were many more occasions for organisms to be selected by their success in reproducing.

Similar problems arose in the evolution of eukaryotes. The evolution of aquatic balloons enabled colonies of prokaryotes to focus natural selection on the combinations of prokaryotes and made them responsible for their own non-reproductive structural effects, and the evolution of the nucleus enabled aquatic balloons to go through reproductive cycles fast than the circadian cycle. But the increasing power of the eukaryote as a whole entailed a similar weakness about natural selection in eukaryotes, because the kinds of RNA-level and prokaryote-level organisms combined in the nucleus could be selected only by the natural selection of the eukaryote as a whole.

This limitation was less severe in the early in the evolution of eukaryotes, when aquatic balloons regularly disintegrated and had to be reconstructed by the prokaryotes in the region, because that meant that different combinations of prokaryotes were continually being tried out. Aquatic balloon with more functional combinations of prokaryotes would supply more members to be involved in constructing the new aquatic balloon the next day, but the mixing of prokaryotes meant that the evolution of prokaryotes with new powers in some aquatic balloons would soon be found in other aquatic balloons.

But as combinations of prokaryotes became powerful enough to maintain their aquatic balloon through many cycles of night and day, and as they came to reproduce by dividing their aquatic balloon and nucleus into two eukaryotic cells, the combinations could only be selected only by the reproductive success of entire eukaryotes. They evolved in the same way as prokaryotes, even though they were much more complex than prokaryotes and had many more random variations to try out.

Prokaryotes evolve by branchings and extinctions, so that a favorable random variation begins a whole new lineage. That lineage may exist alongside the other kinds or replace them, but other lineages cannot acquire the favorable mutation, unless their own random variations happen to try out a similar trait. This was enough for the evolution of prokaryotes, but eukaryotes were on a higher level of biological organization, and this compounding of complexity meant that reproductive causation would take much longer to approach natural perfection. And the more complex eukaryotes became, the longer gradual evolution would take.

Thus, the benefits of greater power that come with their higher level of biological organization and greater complexity tended to be lost because of the cost of slowing down the pace of gradual evolution.

Sexual reproduction. Eukaryotes solved this problem by happening on a way of accelerating the pace of gradual evolution. It was sexual reproduction, or the mixing of the structural causes bundled together in the complex material structure of eukaryotes as part of their process of reproducing.

The function for which this innovation was selected was accelerating the pace of gradual evolution. Those eukaryotes that tried it out were able to evolve faster, and thus, they were naturally selected because of their greater power.

The most obvious way of accelerating gradual evolution comes from how sexual reproduction makes it possible to combine favorable traits that evolve in different individuals. When random variations are functional in a eukaryotic cell, it does not start a new lineage by asexual reproduction, as in prokaryote evolution. Instead, sexual mixing as part of the process of reproduction makes it possible for favorable random variations that occur in different individuals in one generation to be combined in a single individual in a later generation. Thus, functional traits can be accumulated from different individuals in single individuals, combining their powers.

The sexual mixing also accelerated gradual evolution by focusing natural selection on the lower level organisms of which eukaryotes are parts. In effect, it internalized reproductive causation so that the lower level organisms of which eukaryotes are composed would gradually change in the direction of greater power in their ecological niche as parts of eukaryotes. At any point in the evolution of sexually reproducing eukaryotes, only the most powerful bundles of lower level organisms would exist, because they would be naturally selected. At that point, what makes some eukaryotes more powerful than others would depend only on differences in certain of their lower level structures, and since they would be the only parts that distinguish them after sexual reproduction, the natural selection of the whole eukaryote would turn on their contributions to the power of the eukaryote as a whole. Natural selection would be focused on different parts at different times in the gradual evolution of eukaryotes, because the powers that it is possible for them to evolve at that point would depend only on certain lower level parts and how they work together with what has already evolved to control relevant conditions. Thus, as natural selection shifted from one part of the eukaryotic structure to another, eukaryotes would become increasingly powerful.

The mechanism of sexual mixing means that natural selection can be focused on structural causes at both levels of biological organization below eukaryotes. The shuffling of chromosomes from different parents in the process of reproduction tries out different combinations of DNA level structural causes, and that was probably the original form of this mechanism, because the nucleus had evolved as a mechanism for handling whole chromosomes.

But eukaryotes also evolved a way of extending this effect to the RNA level structural causes of which prokaryotes are composed, that is genes. "Crossing over," as it is called, is a process in which segments of the paired chromosomes from different parent are recombined before being separated from one another and bestowed on different cells. Thus, sexual mixing affects the combinations of units of behavior that make up eukaryotic behavior at both lower levels of biological organization.

Furthermore, the shuffling of chromosomes (and crossing over between them) meant that a far wider range of random variations would be tried out by each generation.

Finally, when eukaryotes evolved the trait of carrying two copies of each chromosome (diploidy), it was possible to preserve genes that might turn out to be useful later or in different combinations with other genes.

The advantages of sexual reproduction are general and would have accelerated the evolution of prokaryotes as well as eukaryotes. But the rigid cell walls of prokaryotes made it difficult for sexual mixing of DNA to be a regular part of reproduction, whereas it was relatively easy for eukaryotes.

In eukaryotes, the self-forming nature of plasma membranes made it relatively easy to mix parts of their DNA, because that enabled different eukaryotes to merge into a single cell. Moreover, from the beginning, in order to reproduce at all, the eukaryote had to replicate each chromosome in its nucleus, separate the copies, divide its nucleus, and bestow one copy of each chromosome on the nucleus of each half of its dividing outer cell (mitosis). Since it already had mechanisms for handling multiple chromosomes and putting them in the nuclear plasma membranes it constructed, the eukaryote could evolve a mechanism that would shuffle the chromosomes from different cells when they merged, separate chromosomes of the same kind from one another, and bestow a nucleus with one complete set on each half of the dividing cell. This second way of dividing of dividing the cell (meiosis) would account for the various patterns of sexual reproduction found in extant eukaryotes.

To be sure, bacteria, such as E. coli, have a process, called conjugation, which accomplishes much the same thing, although it is not part of reproduction. These prokaryotes construct a cytoplasmic bridge between them and exchange segments of DNA, called “plastids.”

But conjugation is not common in prokaryotes, and it may reflect the selection pressures of being confined to the digestive tracks of multicellular animals. Conjugation enables E. coli to share the mutations by which they can consume new kinds of energy-rich molecules, which stem from changes in the animal's diet. Not only were their non-conjugating cousins not selected, but neither could the animals that lacked conjugating E. coli survive when radical changes in diet were required.

Life began about 3.5 billion years ago, less than a billion years after the formation of the planet, and eukaryotes evolved between one and two billion years ago. But the evolution of sexual mixing during reproduction would explain why evolution has taken less time to reach its present state than it took for prokaryotes to evolve into eukaryotes.

Species. Another dramatic effect of sexual reproduction on the nature of the ontological cause of evolutionary change was to advent of true species. The ability to mix genes sexually with one another makes eukaryotes members of a species that share a common gene pool. Since parts of their complex material structures from the lowest level of biological organization (the RNA level) are regularly mixed in constructing new organisms, there is a sense in which what is evolving is not the organisms, but the gene pool species. The gene pool is just all the genes in the particular organisms that are capable of sexual reproduction and, thus, make up the species.

This does not mean, however, that the gene is the “unit of selection,” as many contemporary Darwinists would have it. The unit of selection is determined by the ontological cause of gradual evolution, or the reproductive cycle, and that depends on the whole organism. The whole reproducing organism is what is naturally selected, because that is the complex material structure that does all the non-reproductive work, the structure that is reproduced, and the structure whose reproduction imposes natural selection on itself.

When the individual organisms are mixing their genes sexually, however, what makes some individuals more powerful than others at any point in their evolution usually comes down to a few genes that are responsible for the differences between their traits at that point. Natural selection is focused on those genes because they affect the reproductive success of the organisms. But that does not mean that the gene is the “unit of selection.” That is just an appearance, which is due to the way in which sexual reproduction makes reproductive causation more efficient. Though the sexual mixing of genes during reproduction has the effect of focusing natural selection on the genes, it is still the reproducing organisms that are being selected by their success in reproduction. And the frequency of genes in the gene pool is merely a useful way of describing the change taking place in the evolution of species by the natural selection of reproducing organisms

Indeed, in organisms that can reproduce only sexually, the unit of selection is not the individual organism, but a larger unit, the mating pair. The individual organism is not a complete bundle of the structural causes that is going through reproductive cycles; it not the material structure that is responsible for the reproductive cycle. Since only a pair of organisms can reproduce, each individual is just half of the material structure that is responsible for the whole cycle of reproduction. Each individual organism must seek its other half in order to be complete. What obscures the unit of selection is that the other half of the reproducing organism is not determined until mating actually occurs.

Even in organisms that can reproduce asexually, the mating pair is a unit of selection, because as long as they can reproduce sexually, that will involve a much more efficient form of natural selection and the mating pair will be the organism that is responsible for the reproductive cycles that constitute gradual evolution.

Eukaryotes drop sexual reproduction only when they occupy stable ecological niches in which they have already reached maximum holistic power for organisms of their kind. But if the environment were to change, closely related species that still reproduce sexually would adapt faster and replace them.

Furthermore, with the evolution of multicellular animals, the unit of selection is sometimes even more inclusive, because multicellular organization enables generations to live side by side.

In protists, or single-celled eukaryotes, sexual reproduction means death to the individual organism, because individual organisms must merge with one another in order to mix their genes in the process. But multicellular organisms do not need to die in order to reproduce. They can set aside special cells for that function, because multicellular organisms reproduce, as we shall see, from a fertilize egg cell. The multicellular organism can, therefore, live side by side with their offspring after reproducing.

Many kinds of animals take advantage of this fact to control more of the conditions affecting their reproduction, for example, by caring for their offspring. Thus, their offspring may go through periods when they are unable to fend for themselves before they take on the adult role of parents themselves. To the extent that a species comes to depend on this generational overlap, the reproducing organism may include not only the parents, but also their offspring, that is, the whole family. In that case, the unit of selection is the multi-generational entity, or “composite organism,” that includes, at least, periods during the cycle when two (or more) generations live side by side and do the non-reproductive work of controlling conditions that affect the reproduction of them all.

In addition to parental behavior that nurtures and protects offspring, the traits that may evolve because of this larger unit of selection include behavior in the offspring that contributes to the maximum holistic power of the composite reproducing organism, such as dispositions to follow parents and altruism toward other parts of their composite organism. This accounts, I would argue, for what is called "kin selection", which will be discussed later.

There are, as we shall see, even larger units of selection, if evolution is due to reproductive causation. But the cause is not the sexual nature of reproduction. It is group-level selection, and it may cause the evolution of composite organisms at the same time mating pairs and families are evolving by their natural selection.

4. Multicellular stage: embryological development.Higher levels of part-whole complexity in the structure of organisms are ontological causes of stages of evolution, and we have seen how three levels of biological organization are responsible for three stages of evolution (molecular, prokaryotic, and eukaryotic). It is obvious that there is a higher level of part-whole complexity than single-celled eukaryotes, for there are organisms composed of eukaryotic cells that are simply attached to one another. And a new stage of evolution does seem to have been caused by the appearance of one kind of multicellular organism, at least, for the Cambrian revolution some 600 million years ago, which is virtually the beginning of the fossil record, is the first evidence of multicellular animals.

In order to prove the inevitability of another stage of evolution, however, we must show that a higher level of biological organization is both possible and can bring an entire new range of conditions affecting reproduction under control. Once again, the function of a higher level of part-whole complexity is obvious, because organisms are larger on the multicellular level and they can deploy the behavior of whole armies of lower level organisms. But it not so obvious how it is possible, because the capacity to coordinate the behavior of lower level organisms is more than simply bundling them together as parts of a higher level organism. It requires the capacity to coordinate their behavior (including their reproduction) to do non-reproductive work. As in the eukaryotic stage, therefore, the main challenge at the multicellular stage of evolution is showing the possibility of a biological behavior guidance system on a higher level of part-whole complexity.

Multicellular animals, rather than plants, will be our main focus, because they begin the series of evolutionary stages that lead up to beings like us. We shall focus, therefore, on the mechanism of embryological development in multicellular animals and even trace its origin. But then, in order to law the foundation for tracing the neurological stages of evolution in multicellular animals, we shall draw back and consider animals more generally, both the basic nature of animals and all the possible kinds of animals, basic and anomalous.

The possibility of multicellular animals.In order for organisms to evolve at the multicellular level, it must be possible for complex material structures to do both kinds of work required to go through reproductive cycles. One kind of work is reproduction, and at the previous levels, the higher level organism was able to reproduce by coordinating the reproduction of the lower level organisms of which it was part. But that is not possible at the multicellular level of biological organization, at least, not in animals in which the pace of evolution depends on sexual reproduction.

Prokaryotes reproduce by replicating all the genes on their loop of DNA, and eukaryotes reproduce by replicating their chromosomes (and self-reproducing organelles in the cytoplasm). But what makes that possible is their biological behavior guidance system. In both cases, it is possible to coordinate the behavior of the lower level organisms, because the lower level organisms are parts of the biological behavior guidance system and they contribute to the behavior of the organism as a whole by how they move and interact within that more inclusive structure.

Multicellular organisms, by contrast, are just eukaryotic cells attached to one another, and since each contains all the structural causes of its own behavior, they would never be anything more than just colonies of eukaryotic cells, if multicellular organisms reproduced only by each of the cells reproducing itself. They could evolve such cooperative behavior by group level natural selection, but it would be very inefficient, like the evolution of RNA at the molecular stage and the colonies of prokaryotes from which eukaryotes evolved. What they need is a biological behavior guidance system to coordinate their behavior. But anything like the nucleus in eukaryotes or even the cell-enclosed loop of DNA in prokaryotes would be far too cumbersome. And even if it were possible, it would either have to give up the advantages of sexual reproduction or evolve a new way of sexually mixing the structures of its lower level organisms in the process of reproducing on the multicellular level.

What makes it possible for multicellular organisms to have a biological behavior guidance system is that the cells of which it is composed can all be generated by the asexual reproduction of a single cell. And since it is generated from a single cell, multicellular organisms can evolve in the efficient way made possible by the sexual mixing of the lower level organisms of which they are composed, because the cell from which they are constructed can be a fertilized egg cell derived from different multicellular organisms in the previous generation.

At the multicellular level, in other words, the biological behavior guidance system is originally located within a single eukaryotic cell, and it is able to coordinate the behavior of all the eukaryotic cells making up the multicellular organisms because they are all its offspring and their behavior is coordinated from the beginning of their lives. This is what I will call the “mechanism of embryological development.”

Since the behavior of the eukaryotic cell is guided by the nucleus, this coordinating mechanism must be a modification of the nucleus. The plan for the behavior of every kind of cell in the mature multicellular organism must be contained among the chromosomes in the nucleus, and thus, a copy of the entire multicellular plan is bestowed on each daughter cell. But in order for each cell to generate its distinctive behavior, it must express only some of the genes on certain chromosomes, and that means that each cell must be able somehow to identify itself with one kind of cell in that plan, for otherwise the entire genetic plan would not affect different cells differently. A rather major modification of the nucleus is required to make the chromosomes in each cell express their genes in a way that is distinctive for cells of its kind, and it works only because the cells all come into existence in a unique way as offspring of the original fertilized egg cell

The mechanism of embryological development. The mechanisms of embryological development are only now being discovered, but in multicellular animals, at least, it must enable the nucleus of different kinds of cells to operate in basically different ways. Though such a mechanism is not problematic in the case of plants, animals need a more complex multicellular structure and that does pose a problem.

It is not difficult to see how plants could have evolved from single-celled eukaryotes. The mechanism responsible for constructing their multicellular organization is a simple variation on the eukaryotic behavior guidance system, which can reproduce asexually as well as sexually. In this case, daughter cells from the asexual reproduction of an original cell remain attached to one another and cells differentiate according to a gradient of messenger proteins (hormones) maintained throughout their extra-nuclear cytoplasms. Even a two-cell organism would be an advantage in completing a reproductive cycle, if one cell attached itself to the ground while the other grew out from it toward the sun. Not much of a change is required to establish a gradient from one end of the composite whole to the other, since single eukaryotic cell can already respond to molecules in the environment and orient themselves to electromagnetic radiation. What is required is a mechanism that would use the gradient of to open up the chromosomes of difference cells in different ways. Moreover, once it evolved, reproductive causation could easily come up with more complex plants, because during the whole process of development, the cells can be acquiring energy from photons. A complex process could evolve by adding step to a simpler process. In fact, plants probably evolved from plant-like protists many different times. For example, the spherical colonies of plant-like protists that float in the water (the Volvox series) appear to have evolved independently of plants that attach themselves to the ground with a holdfast.

There is, however, something quite puzzling about the evolution of multicellular animals, at least, in those that become most powerful, because they have bodies that are complex enough to require a nervous system to guide them. Their process of embryological development can also use gradients of messenger molecules to give cells different kinds of behavior, but something more is needed in the case of multicellular animals, because in order to set up a complex body, masses of cells (or even individual cells) must move in relation to one another in a regular pattern. Daughter cells cannot remain attached to one another in a fixed spatial relation.

Animals evolve from cells that are, unlike plant-like protists, capable of locomotion, and thus, coordinating them can involve coordinating their locomotion as well as other kinds of behavior. That means that the multicellular biological behavior guidance system in animals must be able to alter certain cells and their daughter cells early in the process so that, subsequently, they behave in ways that do not depend solely on the messenger molecules in the neighborhood (and can determine other cells they encounter to become cells of a specific kind as well). Once the structure of multicellular body is set up, the behavior of all the cells can be coordinated by the distribution of messenger molecules (hormones) throughout the body, because they will have different effects on different kinds of cells.

Moreover, embryological development in animals is not only more complex than in plants, but it is also quite puzzling how it could have evolved in the first place, because animals cannot acquire energy for themselves until the body is formed and they are able to ingest other living objects. The entire process of embryological development must be set up in advance with an adequate supply of energy in a fertilized egg, and the problem is how such an elaborate process could have been tried out as a variation during the gradual evolution of animal-like protists.

Such an elaborate coordination of animal-like protists cannot be simply an adaptation of the eukaryotic biological behavior guidance system, but requires a new structure in the fertilized egg cell that can construct a multicellular animal body from its offspring and coordinate their behavior. Such a process could be generated as a structural global regularity with just a few mechanisms.

There is evidence that what determines a cell to certain kinds of behavior rather than others are "homeobox genes", or master genes that activate or repress the expression of subordinate genes on nearby segments of their chromosomes.

And it is possible to alter cells (that is, “determine” cells) so that even their offspring have special kinds of behavior. For example, if what controls which segments (and, thus, which homeobox genes) are opened up were a self-forming complex of protein molecules that becomes attached to the DNA molecule at certain points, they could be reproduced when the cell reproduces, because one half of the protein complex could remain attached to each of the strands of DNA being copied so that subsequently, after it had synthesized its complementary strand of DNA, each half of the protein complex could attract the other half of the self-forming complex. Thus, daughter cells would have protein markers attached to its chromosomes that make them behave differently.

It is possible for the fertilized egg cell to determine its daughter cells at the very beginning so that they act, thereafter, in basically different ways from one another, independently of the hormones that they may encounter, because different daughter cells inherit different parts of its cytoplasm. If different messenger molecules were located in different parts of the fertilized egg cell, they would wind up in different groups of cells after the first few divisions, and the process of embryological development would begin with different groups of daughter cells having basically different kinds of behavior, including locomotion relative to one another.

Even though a multicellular animal is, at one point in its reproductive cycle, just a single cell (a fertilized egg cell), it must be counted as a higher level organism, because that cell is the structural cause of embryological development. Embryological development is a complex structural global regularity whose outcome is a complex organization of various kinds of cells in which the behavior of the cells is coordinated by the exchange of messenger molecules. And since the complex material structure responsible for this global regularity goes through reproductive cycles with both essential kinds of behavior, it evolves by reproductive causation toward natural perfection for organisms of its kind.

To be sure, multicellular animals are different from prokaryotes and eukaryotes. Prokaryotes and eukaryotes have the same level of organization throughout their reproductive cycles, whereas multicellular animals have a period during which they are at the eukaryotic level of biological organization. But that merely reflects the nature of their biological behavior guidance systems. In prokaryotes and eukaryotes, the biological behavior guidance system is the an aspect of the structure of their highest level of biological organization, whereas in multicellular animals, the basic structural cause is located in a single cell, the fertilized egg cell. But since it is clearly the structural cause of a multicellular organism, there is no reason to doubt that it is on a higher level of biological organization.

Levels of biological organization are basically levels of part-whole complexity in space, but as we have seen, they also typically involve levels of part-whole complexity in time. That is, a single reproductive cycle at the higher level may include many reproductive cycles of the lower level organisms of which they are composed. Prokaryotes and eukaryotes both use many cycles of the RNA molecule’s reproduction in doing their non-reproductive work, because it depends on transcribing segments of the their DNA as mRNA and then using them to guide protein synthesis. And in eukaryotes, mitochondria and chloroplasts may go through many reproductive cycles during a single reproductive cycle of the cell as a whole. In addition to incorporating lower level reproductive cycles, a single reproductive cycle of a multicellular animal uses many eukaryotes reproductive cycles to construct a multicellular body. The main difference is that multicellular animals use many cycle of the reproduction of the lower level organisms not only to do non-reproductive work, but also to reproduce themselves. But that is not a reason for doubting that they are on the multicellular level of biological organization.

These general points about its nature show how a new kind of biological behavior guidance system is possible, in principle, at the multicellular level. That is, there is little reason to doubt that the mechanism of embryological development would eventually be tried out as a random variation during the evolution of eukaryotes. Since the greater power of multicellular animals is hardly in doubt, we can conclude that the multicellular stage of evolution was inevitable.

The section at the end of this chapter uses what is known about the simplest multicellular animals on earth to explain how the origin of the mechanism of embryological development can be traced to single-celled eukaryotes.

Animals. Though the evolution of multicellular plants may also involve a series of stages, nothing more will be said about them here, because the current project is to show that there is a series of inevitable evolutionary stages leading up to rational beings like us (and beyond). The evolution of multicellular plants is a separate branch of evolution. But to lay the foundation for tracing the evolution of animals through a series of inevitable stages to rational beings like us, let us first consider the basic nature of animals and inventory the kinds of animals that can evolve, both basic and anomalous.

That will leave us to consider, in subsequent chapters, the differences among animals that depend on in levels of neurological organization at the multicellular stage. The social level of biological organization will be introduced by way of insect colonies, for they are an example of the anomalous animal that will be explained in this catalogue. Though human society is also an animal on the social level, it depends on the stages of animal evolution caused by levels of neurological organization, and thus, there is not much to say about it until after we trace the stages of animal evolution.

The Nature of Animals. The difference between animals and plants (and plant-like organisms) is part of the differentiation of organisms into kinds that occurs at each stage of biological evolution. What makes animals different from plants is not their level of part-whole complexity, but that animals acquire the free energy (and parts) they need to fuel their reproductive cycles by ingesting other objects in space. Those objects are not mere photons, but material objects, with rest mass — sometimes just energy-rich molecules, but usually other organisms.

Animals require, therefore, a kind of behavior that is radically different from anything plants require. In order to ingest other objects in space, animals must have a kind of behavior that acts on them, whereas plants (and plant-like organisms) need only behavior that acts on the world as a whole at the moment. Though plants often need to orient their bodies and their behavior in the world, they act, at most, only in some direction relative to a field in space, such as gravitation, in the direction of electromagnetic radiation, or relative to gradients of water in the soil, the magnetic field, and the flow of air or water. Such behavior is not directed toward particular objects in space, but merely affects whatever objects may be located in the direction in which its behavior is oriented. By contrast, no animal, regardless how simple, could not control even the most basic condition that affects its reproduction as an animal, unless it could direct its behavior toward particular objects in space. Thus, we might say that, whereas plant behavior acts on the whole world at the moment (or, at most, some direction in space), animal behavior acts on objects in space.

A new system is required to guide the animal’s special kind of behavior, because ingesting other objects is a hazardous way of making a living. Ingestion is an intimate way of relating to another objects, and since there are usually many kinds of objects around that would harm the animal, if ingested, animals must have a mechanism of some kind by which to tell in advance which objects to ingest and which to pass up. Eating and not eating are incompatible behaviors with respect to any given object in space, and selecting which objects to eat is, therefore, a condition of the existence of reproductive cycles fueled in this way. Such a basic function may well be called a "need," and thus, needs, like functions, can be used to explain the traits that evolve.

That is, there are various ways of doing non-reproductive work within the range of random variations being tied out, and those that make it possible for organisms to acquire energy as animals do will be selected by their power to control that relevant condition. Thus, reproductive causation implies that organisms with animal behavior guidance systems will evolve, if they are possible.

The animal behavior guidance systemis a second system for guiding behavior in most animals, because as living organisms, animals already have a system that selects between incompatible kinds of behavior, namely, the biological behavior guidance system. Such a mechanism is needed to coordinate the behavior of the lower level organisms that are bundled together as the higher level organism, and it is responsible for guiding the organism’ through its reproductive cycle.

The first such biological behavior guidance systemwas at the prokaryotic level. It was necessary, as we have seen, because the two kinds of work that the first organisms had to perform during each cycle in order to evolve, growth and reproduction, were incompatible and could not be generated at the same time. Its origin during the prokaryotic stage marked the beginning of life, since the ability to select and generate both kinds of behavior is what enabled organisms to go through reproductive cycles on their own, independently of the cycle of night and day. That gave them the autonomous activity ordinarily meant by saying that something is alive, and as living organisms, that make themselves evolve.

At each subsequent stage of biological organization, a new biological behavior guidance system was needed, because it was necessary to coordinate the behavior of the new kind of lower level organisms that are bundled together and go through reproductive cycles as a whole. Since, at any biological level, animals already have a biological behavior guidance system, and he animal behavior guidance system is their second system for guiding behavior, one whose function is to guide the special kind of behavior that animals need in order to acquire free energy by ingesting other material objects in space.

The reason for calling both mechanisms "behavior guidance systems" is that they similar kinds of functions. In both cases, a basic choice must be made between incompatible kinds of behavior in order for organism of their kind to go through reproductive cycles at all. For organisms to be alive, it is the choice between growing and reproducing, whereas for living organisms to be animals, it is the choice between eating a particular object and not. There is no way to avoid making such a choice in either case, for the two essential kinds of behavior cannot be generated at the same time. (It is less inconvenient in multicellular organisms, with their unique way of reproducing, because this choice is made when cells are determined to have different functions and some are assigned the task of reproducing the organism as a whole.) Since the biological and animal behavior guidance systems evolve to serve similar functions, we can discern a basic similarity in their structures, because they must serve similar subfunctions.

A behavior guidance systemis not a mere cybernetic device, as we have seen. Cybernetic systems use feedback from the consequence of their behavior to attain or maintain some overarching goal. But behavior guidance systems are essentially different, because their function is to select between incompatible goals. The difference can be seen in how the behavior guiding function requires mechanisms to serve no less than three sub-functions, regarding input, selection and output.

Input. In order to make the selection among possible goals, input is required about the current state of affairs, either about the world as a whole or about particular objects in space. That means that the system must be affected by the state of the world (including, perhaps, the state of the organism itself) in a special way when choosing one of the alternatives or the other would control the condition that affects reproduction.

Selection. The input must change a state of the behavior guidance system in some way so that the system selects the right goal from the alternatives, which is its basic function. This is the sub-function that a cybernetic system lacks.

Output. In order for its selection to make a difference, the behavior guidance system must also be able to generate the appropriate kind of behavior. Since it is directed at a goal, such output typically has the structure of a cybernetic system, using feedback from the effects of earlier behavior to adjust its output to attain the chosen goal.

Thus, the behavior guidance system's three essential sub-functions are receiving input, selecting the goal, and generating output (which may also use input as feedback). It cannot get by with fewer sub-functions, whereas the cybernetic system, with a fixed goal, requires only a mechanism for registering input and generating behavior accordingly.

The nature of reproductive causation entails, as we have seen, that non-reproductive work is not a means to reproduction as an end in the biological behavior guidance system. The goals of non-reproductive work are the conditions affecting reproduction that must be controlled, whereas reproduction is merely the cause of the natural selection by which they evolve.

Animal behavioritself is different from the kinds of behavior guided by the biological behavior guidance system, because it must be directed at other objects in space, not merely at the world as a whole (including orientation in a field of some kind). The spatial aspect of animal behavior may not be obvious in some cases. It can be just an aspect of the unchanging structure of the animal body as, for example, in sedentary animals that filter the flow of water to feed on smaller organisms. But the spatial aspect is essential, because the free energy that animals use is contained in objects that have locations in space. Those objects must be ingested, and in order for animals to become more powerful, they must acquire traits that take advantage of how their sources of free energy are located in space.

Though the behavior guided by biological system is not directed at any other particular objects in space, but only at the world as a whole, it can still gradually evolve greater power, because it can organize different kinds of behavior in time. As we have seen, the biological behavior guidance system is a higher level structural cause that coordinates the behavior of the many lower level organisms of which it is composed, and it is responsible for all the behavior required to complete a whole reproductive cycle, including both growth and reproduction. Such a complex material structure is what made it possible to explain gradual evolution as a global regularity that is caused ontological by reproductive cycles and the wholeness of space.

Though the cycle of reproduction does not exist fully at each moment, its structural cause does, and since the entire cycle is implicit in a material structure (that is, its biological behavior guidance system) which does exist fully at each moment, the ontological cause of gradual evolution could be described, paradoxically, as a four dimensional object that endures through time and reproduces in space. Thus, implicitly contained in the structure of the biological behavior guidance system are not only both the phases of growth and reproduction, but all the responses to changing circumstances and sequences of behaviors using feedback to attain goals that occur during the entire reproductive cycle.

It may be surprising that nothing but the right sequence of activities at the right times is needed to generate a whole reproductive cycle (except, perhaps, for orienting itself in various fields). But taking advantage of the power to sequence behavior temporally is what enables the biological behavior guidance system to become increasingly powerful at each stage of evolution. In addition to making each behavior as effective as possible in controlling its relevant condition, reproductive causation inserts or deletes kinds of behavior from temporal sequences, changes their duration or quantities, and rearranges their sequences in time. The right sequence (conditioned on relevant input) can be very powerful. That is why the biological behavior guidance system is the locus of most evolutionary changes in such organisms.

This difference between animal and merely biological behavior is ontologically basic, because in addition to any temporal sequencing of behavior that is generated by the biological behavior guidance system, the animal behavior guidance system also imposes a spatial structure on the behavior of the organism by acting on other objects in space. Insofar as the power of the animal behavior guidance system to control what happens increases by taking advantage of the fact that the objects containing free energy have locations in space, animal behavior is superimposing a geometrical structure on the region.

Organisms can evolve only in regions where there is a supply of free energy, and as we have seen, there is a region-wise geometrical structure about the thermodynamic flow of matter from potential energy through kinetic energy (and radiation) toward evenly distributed heat that constitute free (or usable) energy. Thus, we can see animal behavior as channeling the thermodynamics flow in the region. In other words, what most material structures do simply by existing in the region, animals do by acting on objects in space. That is what makes animals more powerful than plants, and it suggests how far animals might evolve in the power to control relevant conditions.

Structural causes generate irreversible structural global regularities by using free energy to do work, that is, making things happen that would not otherwise happen. Though animals are just organisms contained along with other objects in the region, the evolution of behavior that takes into account the locations of other objects in space in order to control conditions that affect their behavior can channel the flow of free energy toward increasing entropy over very large regions of space. In other words, the spatial aspect of animal behavior (being directed at objects in space) imposes a geometrical structure on the region (and, thereby, channels the thermodynamic flow in the region in a way that would otherwise require a material structure as large as the relevant region, like a giant machine or building). The actualization of the potential of animal behavior to do work in the region is what we are tracing by deriving from spatiomaterialism the evolutionary stages that determine the overall course of evolution.

This potential is actualized mainly in multicellular animals because of the evolution of a series of level of neurological organization in them, but before we trace those stages, let us catalogues all the other animals to see how multicellular animals are related to all the other kinds of animals.

Kinds of animals. Stepping back from the multicellular level of biological organization, this explanation of the nature of animals entails a classification of animals into their natural kinds. The basic kinds of animals are easy to classify, because they are ontologically necessary, and identifying them will provide a map of subsequent stages. However, this way of sorting out the basic kinds of animals resolves several puzzles about the classification of animals in biology, and thus, we will conclude with a survey of the kinds of anomalous animals that are just as ontologically necessary.

Basic kinds of animals. Since animal behavior guidance systems evolve at each level, the most basic divisions among animals correspond to the levels of part-whole complexity in the biological behavior guidance system discussed in the last section. We should expect some kinds of animals at each level of biological organization, because animals are just a variety of the living objects that evolved at each stage of evolution. They are, in technical terms, heterotrophs, which acquire the free energy to fuel their structural effects from objects with a rest mass where energy is stored in their chemical bonds. Plants, by contrast, are autotrophs, which acquire energy directly from the sun by absorbing photons.

At the prokaryotic levelof biological organization, the heterotrophs are bacteria. They feed on energy-rich molecules, and their varieties mirror the kinds of molecules they consume.

The animal behavior guidance system at this level need not be very complex. It is a molecular structure in the cell wall that can identify the right kinds of molecules and draw them through the cell wall into the cell to be dismantled inside while keeping dangerous (and useless) molecules outside.

To be sure, autotrophs at this level, such as cyanobacteria, also consume molecules, but only for use as parts in growing (or as input signals), not as a source of free energy. Parts can be acquired without an animal behavior guidance system, because the simplest, energy-poor molecules, which are almost always available as part of the medium both inside and outside the cell and pose no danger, can be used as parts. But animals need a special system in order to ingest large, energy rich molecules, for that poses a hazard.

At the eukaryotic levelof biological organization, the heterotrophs are animal-like protists, or single-celled eukaryotes. They feed mainly on prokaryotes and plant-like protists (algae). But there are several new animal behavior guidance systems, and to suggest their range, let me mention three kinds.

The paramecium has a stiffened cell membrane with an oral groove along one side in which many hair-like cilia sweep small particles into a mouth, where they are enclosed in a vacuole for digestion inside the cell — unless they are harmful and they are kept out. This animal behavior guidance system is clearly independent of the biological behavior guidance system, the nucleus, for when the nucleus is removed, a paramecium continues moving and feeding for many days.

Amoebas have a soft plasma membrane, instead of the stiffened cell membrane that gives paramecia their shape, and amoebas move along the substratum by constructing an extension of the plasma membranes on one side of the body while dismantling it on the other (pseudopodia). Amoebas ingest prokaryotes, algae, and even small animal like protists by wrapping part of their outer membrane around the energy-rich object and then enclosing the package within its cytoplasm as a food vacuole where digestion takes place. Hence, their choice about feeding is made locally in the course of moving about.

Finally, collar flagellates remain attached to the substratum and use the whip-like motion of their flagellum to pull microorganisms to a region near a collar at the base of the flagellum where they can be ingested.

There is one kind of protist, Euglena, whose identity as plant or animal is in doubt, because these flagellates have chloroplasts for acquiring energy from photons and yet also ingest prokaryotes. However, they may be plants, rather than animals, because they probably use their prokaryotic prey for their nutrients, rather than for energy, since what is scarce near the surface of the ocean which they inhabit are heavier atoms. (This is the kind of scarcity that accounts for animal-like multicellular flowers in rain forests, such as the Venus fly-trap, that ingest animals. But since the objects are ingested for parts, rather than energy, they are not animals by this definition.)

The multicellular levelof biological organization makes possible the most powerful ways of guiding animal behavior, because it uses multiple neurons. Neurons are cells whose structure enables them to transmit signals from one place in the body to another or among themselves, and since neurons are capable of being organized at a series of levels of part-whole complexity, there are differences among kinds of multicellular animals that are nearly as basic as these differences among other kinds of animals.

Multicellular animals direct behavior at other objects by the contraction of muscle cells located where the muscles are needed to change the body’s shape, and neurons generate behavior by controlling the relevant muscles. But behavior must depend on input from the other objects in space in order for animals to choose how to behave towards them and to generate behavior whose spatial aspects will control the outcome of interacting with them, and so neurons must be connected to sensory receptors on which other objects in space have an effect. The choice of kind of behavior depends on the “interneurons” connecting sensory neurons on the input side and motor neurons on the output side (usually in conjunction with input about the state of the body itself concerning its energy needs, mating urges, damage to cells, and the like).

The behavior of the neuron itself is generated, as in all machines, by the geometrical structure of such material objects and how they structure the flow of free energy toward entropy increase in their region. In the neuron, molecular mechanisms in the plasma membrane control of the passage of sodium and potassium ions through its plasma membrane in such a way that an action potential propagates along the axon of the neuron, and that affects the passage of small proteins, called “neurotransmitters,” at the synapses where they meet determines whether a signal is passed on. But the details of the neuron's mechanism are well known and not relevant here.

What is relevant is how they constitute an animal behavior guidance system. Any behavior guidance system, given its function of selecting between incompatible kinds of behavior, must have systems serving three basic sub-functions, and in those that are made of neurons, they will be called the sensory input system, the goal selection system and the behavioral output system.

Among animals with nervous systems, the most basic classification has to do with the level of part-whole complexity in the systems serving the three basic sub-functions. The animal behavior guidance system imposes a geometrical order on the region by how it moves its body around and acts on other objects in space, and there are higher levels of neurological organization in multicellular animals, because they are possible and each actualizes further the power that animals can have by taking spatial aspects of the objects on which they act into account in guiding their behavior in relation to them. The levels of part-whole complexity occur in the three basic systems making up the animal behavior guidance system, and given the ontological explanation of revolutionary evolution, they lead, as we shall see below, to three additional stages of evolution in multicellular animals. Somatosensory animals are the first animals to evolve at the multicellular level, and three additional stages occur because of levels of neurological organization: telesensory (most invertebrates and non-mammalian vertebrates), subjective (mammals), and manipulative (primates).

At the social levelof biological organization, there are two basically different kinds of animals, only one of which has a new kind of animal behavior guidance system that is possible only at the social level. That is the spiritual animal, which is made up of primates as its lower level organism. The same behavior guidance system serves as both its biological and animal behavior guidance system, because the behavior of many individual primates is coordinated so that the spiritual animal acts as a whole by the use of language. The capacity to use language depends on the evolution of additional levels of neurological organization, which determines a series of stages of evolution (though, as we shall see, the last level does not require any change in the biologically inherited structure of the nervous system).

Primitive spiritual animals are groups of primates with the capacity to use a language of natural sentences (that is, sentences with a simple subject-predicate grammar). The linguistic level of neurological organization comes from a higher level of part-whole complexity within the primate faculty of imagination in the so-called “left brain” which enables it to combine the meanings of words as propositions and to indicate the structure of the covert linguistic act involved by verbal behavior (by words and grammatical markers).

Rational spiritual animals are also animals at the social level of biological organization, but they have the capacity to use psychological sentences (that is, sentences with predicates formed of verbs of propositional attitude, such as “believes” and “desires,” together with complete sentences). This linguistic capacity enables the users of language able to think about the causes of their behavior and belief as part of the process of causing them, and so it will called the reflective level of neurological organization. Reflection makes it possible for language to guide individual level and social level behavior in a new way, which involves rational imagination and enables them to understand arguments, and that is the foundation for a new form of evolution by reproductive causation, namely, cultural evolution.

Philosophical spiritual animals are social level animals in which culture has evolved a new level of argument, in which all the arguments of the rational level are organized as parts of a single argument. That is a means of proving that propositions are necessarily true, and thus, it is a new way of discovering the true and the good. Though this is a stage of cultural evolution, it gives the members of the spiritual animals in which it exists a higher level of rational imagination, and thus, it is also the philosophical level of neurological organization. But there are, as we have seen, two ways of constructing such philosophical arguments, epistemological and ontological, and only one of them is able to succeed.

This classification of animals identifies most of the natural kinds, but there is another kind of animal it leaves out. It may be represented by the other kind of animal at the social level of biological organization, or multisomatic animals, such as insect colonies. They have long posed a puzzle for zoologists, because it is not obvious how to classify them. They are social and, thus, like human society, and yet they are so different. But insect colonies are only one of a number of animals that have defied classification, and this ontological explanation of evolution, including both gradual evolution and revolutionary evolution, offers a solution. Thus, we may use the way in which it solve the problem of anomalous animals as a further reason to believe that it is true, before we take up the structure of the nervous system and explain how it works in detail.

Anomalous Kinds of Animals.There is another way that the animal behavior guidance system combines with the levels of biological organization to account for species as natural kinds. Thus far, animals have been classified according to the new kind of animal behavior guidance system made possible by each biological level — as bacteria, animal-like protists, and animals with nervous systems, and spiritual animals. But the same elements can be used to explain the various anomalous kinds of animals.

It requires only that we notice that organisms with the new kind of animal behavior guidance system made possible by one biological level can also be organized merely as so many lower level organisms bundled together as a higher level animal organism. Though it does not have the new kind of animal behavior guidance system made possible by its own level of biological organization, it is still an animal, because it is a heterotroph. Its only animal behavior guidance system is the kind that evolved at the lower level of biological organization. And it has many of them, one in each of its parts.

The most obvious example is the sponge. Sponges are multicellular organisms. And they are animals, acquiring energy from energy-rich objects. But unlike other multicellular animals, they lack a nervous system. The reason is that the sponge is just an organization of collar flagellates, each with an animal behavior guidance system of a kind that evolved in collar flagellates on the eukaryotic level, but put together as a multicellular organism. These animal .like protists are configured like a jar; their flagellums pull water through pores in its side and push it out an opening at the top. Each cell feeds on microorganisms that gather around the collar at the base of its flagellum, and they share their energy with other kinds of cells that hold them together and form pores to the outside. However, the basic choice required by their animal nature is made by the individual cells. The sponge has no animal behavior guidance system as a whole. It would be just a multicellular plant, except that its cells are animal-like rather than plant-like. (See diagram of anomalous animals.)

The cellular slime moldis a similar kind of animal, except that the parts are amoeboid animal-like cells, rather than collar flagellates. When a spore from the cellular slime mold lands where food is available, it feeds, grows and reproduces repeatedly, spreading out as far as food is available. But when food runs out, they all move back toward the center, climb on top of one another and form a slug-like animal, which may move around as a unit for a while. Eventually, however, it becomes a stalked, fruiting body from which new spores are released to try their luck at finding new feeding areas. The biological behavior guidance system coordinates their behavior, using messenger proteins to determine the cells to have different kinds of behavior. Their bodies become polarized front to back; each secretes messenger molecules from one end and moves toward the same molecules that are secreted by others. However, the choice required by its animal nature, between feeding or not on the objects it encounters, is made by the animal behavior guidance systems of its amoeboid members. (See diagram of anomalous animals.)

Fungi are so anomalous that they are almost always classified as a third kingdom, separate from both plants and animals. But the recognition that the only animal behavior guidance system that some animals have is an animal behavior guidance system located in their parts that evolved at a lower level of biological organization reveals that fungi are animals of an anomalous, but natural kind.

Fungi are basically eukaryotes, because they have a nucleus. But their animal behavior guidance system is at the prokaryotic level. Fungi acquire energy by ingesting energy-rich molecules (usually after secreting special proteins to promote decomposition outside their bodies), and thus, they need only the prokaryote's mechanisms for selecting which kinds of molecules to admit and which kinds to exclude. Many such mechanisms are located in their cell wall.

In fact, this prokaryotic animal behavior guidance system is organized on two higher levels of biological organization. There are fungus-like protists, such as yeast, at the level of the single-celled eukaryote, and there are fungi, like mushrooms, at the multi-cellular level. (Multicellular fungi are actually multi-nucleated organisms, because their many nuclei inhabit an interconnected labyrinth of cell walls containing many prokaryotic animal behavior guidance systems operated jointly. A multi . nucleated structure is possible, because fungi have no mitochondria to keep under control. But the reason that they lack mitochondria is probably that the prokaryotes from which fungi acquired their animal behavior guidance system did not use the oxygen-consuming process to extract energy from energy-rich molecules.)

There are, therefore, three levels of animals with the simplest kind of animal behavior guidance system: bacteria, single-celled fungi, and multicellular fungi (see diagram of anomalous kinds of animals).

Finally, this same way of combining animal behavior guidance systems with levels of biological organization accounts for what might be called “multisomatic animals,” including insect colonies, hydrozoa (colonies of hydra), corals, and the colonies of blind mole-rats in East Africa. In each case, the only animal behavior guidance systems are the nervous systems contained in the multicellular animals of which the multisomatic organism is composed. Thus, the organism's behavior as a whole depends mainly on the biological behavior guidance system at the multicellular level, and it reproduces as a whole. (See diagram of anomalous animals.)

In insect colonies, for example, the mating flight of the queen sets up a whole new colony composed of her offspring. But sexual reproduction involves the construction of a entire new colony from a fertilized egg cell (at the eukaryotic level). Thus, it must construct organisms at two levels of part-whole complexity. After constructing the queen’s body, her body is used to construct the other members, and the queen becomes the center of a multisomatic structure in which pheromones are used to coordinate the behavior of her multicellular offspring (the same mechanism used to coordinate cells at the multicellular level).

The limitations of such a mechanism are worth noting. It must make sure that pheromones are received by the right animal parts, but since its multicellular parts do nor remain attached to one another like cells in a multicellular organism, the biological behavior guidance system must require the multicellular animals to have certain unchanging spatial relations, or else it could not use the locations of the pheromones to give them different kinds of behavior. Thus, multisomatic organisms have hives, labyrinths of tunnels, or the like in which pheromones can be distributed, and though its parts have locomotion, the whole multisomatic organism is basically sedentary.

All the kinds of animals, including these anomalous heterotrophs, fall naturally into one or another of the categories generated by combining the concept of an animal behavior guidance system with the concept of levels of biological organization. Animals that lack the new kind of animal behavior guidance system that evolves at their own level of biological organization are made of lower level organisms each with the animal behavior guidance system that evolved at a lower level of biological organization.

The classification of insect colonies as an anomalous kind of animal at the social level does suggest, however, that a new kind of animal behavior guidance system may be possible at the social level of biological organization. That is the possibility realized that is realized in a unique way by the evolution of language among manipulative animals, that is, as spiritual animals.

Neurological Stages of Evolution. We have used the series of levels of biological organization to trace the course of evolution up to the stage of multicellular animals, and, together with the explanation of the animal’s need for an additional behavior guidance system, we have catalogued all the basic kinds of animals that come to exist in the course of evolution, including the seemingly anomalous animals. At this stage of biological evolution, we take up the evolutionary stages that depend on levels of neurological organization, and as we have seen. Those stages fall into two distinct series, the animal stages of evolution and the spiritual (animal) stages of evolution, depending on whether they also involve the evolution of an animal on the next higher biological level as well. The animal stages of evolution will be discussed here, and the new wrinkle involved spiritual stages of evolution will not be discussed further until we take up the eighth stage, primitive spiritual animals.

The ontological cause of the animal stages of evolution is, as we have noted, less basic than the ontological cause of the stages of biological evolution, because the causes are levels of part-whole complexity that occur within the animal behavior guidance system at the multicellular level, that is, in the nervous system.

Each new stage is caused by a higher level of part-whole complexity in the organization of neurons, and though that means that what evolves is a basically different kind of animal behavior guidance system, new animal behavior guidance systems are quite different from new biological behavior guidance systems, because they do not have to coordinate the behavior of the lower level material structures of which they are composed. What enables the biological behavior guidance system to guide the behavior of a higher level organism as a whole is coordinating the behavior of the lower level organisms of which it is part. (And as we have seen, they always use the reproductive behavior of their parts in order to generate some of its non-reproductive behavior). These animal behavior guidance systems are composed of lower level organisms, namely, neurons, which are organisms at the eukaryotic level. But their behavior (including their capacity to reproduce) has already been coordinated by the multicellular biological behavior guidance system in constructing the nervous system during embryological development. (And higher level structures of neurons are not even able to reproduce as a whole, that is, apart from the multicellular animals which they are part.)

Instead of coordinating the behavior of neurons, animal behavior guidance systems use the structure that neurons have been given in embryological development, for it is the structure of the nervous system that enables them to guide the behavior of the animal in acting on other objects in space and moving around in space. Neurons can be used to guide behavior, because they have another kind of behavior, called “firing,” by which they can affect one another. Neurons are structural causes of an action potential that propagates along their long axons and that can, upon arriving at a synapse, cause other neurons to fire or muscle cells to contract. (That is, the connection between the stimulation that makes the neuron fire and the neuron’s effects on other cells is an irreversible structural global regularity, or a disposition. and the neuron’s structure is the ontological cause that explains the connection between the efficient cause and its effect.) But what neurons do to other cells when they fire depends on how they are laid out in the structure of the multicellular body, that is, which other cells they affect, and that structure is a contribution of the biological behavior guidance system.

It is levels of part-whole complexity in the structure of the nervous system that cause the series of stages in the evolution of multicellular animals. It is a minor series by comparison with the stages of biological evolution, for it contained within one of the biological stages. But these animal stages are no less essential to the overall course of evolution in the direction of the natural perfection of life. And as in the case of stages of biological evolution, in order to show that animal stages are inevitable, it is necessary to show that each higher level is both possible and functional.

Animal systems of representation. The challenge of showing the inevitability of animal stages of evolution is just opposite to the challenge in the case of biological stages. It is the function, rather than the possibility of such levels that is problematic.

The possibility of another level of biological organization was the main challenge in showing the inevitability of another stage of biological evolution. But the possibility of higher levels of neurological organization is not very problematic (though there is still something to be shown). The nervous system is constructed by the multicellular biological behavior guidance system, and since that is the mechanism of embryological development, even very complex nervous systems do not seem to be beyond its reach. (And as we shall see, the inevitable limits to the complexity of multicellular structures that can be constructed by it are overcome by a form of reproductive causation that is contained in the nervous system as parts of the process of neurological development.)

On the other hand, whereas the function of higher levels of biological organization was obvious in the size and scale of the behavior they afford, the function of levels of higher levels of neurological organization is not obvious. Indeed, most levels of neurological organization are not even currently recognized in neurophysiology. We begin, therefore, with the basic function of higher levels of neurological organization.

The basic function of all higher levels of neurological organization is to serve as an animal system of representation. This function derives from the nature of animal behavior, and thus, it is part of the animal behavior guidance system. And more complete ways of serving this function depend on higher levels of neurological organization.

Animals need an animal behavior guidance system, because in order to acquire the free energy needed to fuel their reproductive cycles, they must act on other object in space. They cannot sit back and absorb photons like plants. But in order to guide behavior to act on other objects in space, the animal behavior guidance system needs to take into account not only the kind of object, but also its location. Though the kind of object is relevant in selecting the kind of behavior to generate, its location is relevant in generating behavior that is directed at the object, whatever goal is chosen. And this spatial aspect of its behavior is, as we have seen, a source of potentially great animal power.

Increased animal power can come from making the spatial aspects of their behavior depend on the spatial aspects of the situation with which it will engage. By imposing a geometrical structure on a wide region of space, such animals can use the free energy there to do work — much like a giant machine in the region, except by the more efficient means of moving an animal body around in space and acting on particular objects locally.

In the first instance, therefore, what the animal needs to be more powerful is some way of determining how to move around in space relative to objects in order to put its body in a position to act in the appropriate way, whatever its goal. Even more power to cause changes in a large region that would otherwise not occur would come from being able to anticipate the effects of motion on locations. Still more power would come from the ability to anticipate the effects of the geometrical structures of objects on how they interact. Though such spatially adapted animal behavior would require more free energy than sedentary life, the additional relevant conditions it could control more than covers the cost.

The mechanism that actualizes this possible power must be part of the system that is responsible for guiding animal behavior, that is, part of the animal behavior guidance system.

Like any behavior guidance system, as we have seen, the animal behavior guidance system must serve three subfunctions in order to select between incompatible kinds of behavior. It must register input, select the appropriate kind of behavior, and generate output. In multicellular animals, these subfunctions are served by systems made of neurons, and they will be called, respectively, the sensory input system, goal selection system, and behavioral output system.

Sensory input already has the function of representing the object in the animal behavior guidance system. But in order for animal behavior to be adapted to the spatial aspects of the situation, the sensory input system must work together with the behavioral output system, as a system for representing all the possible ways adapting animal behavior spatially.

Sensory input must enable the animal behavior guidance system to select the appropriate kind of behavior toward the objects that the animal encounters. The object may be food, a predator, a mate, or whatever, and the animal behavior guidance system must generate behavior that is appropriate to it, such as, ingesting the object, escaping it, mating with it, or whatever. (Though animal behavior includes mating, it is all non-reproductive work as far as the biological behavior guidance system is concerned, because animal behavior, as such, is just a special kind of behavior generated during the growth phase of the reproductive cycle. Mating is just another way of preparing the conditions for the biological behavior of sexual reproduction.)

But whatever the goal of animal behavior, animal behavior is more powerful when it is adapted to spatial aspects of the situation, and that is another function of sensory input. But to serve this function, the sensory input system must work together with the behavioral output system, that is, as an animal system of representation.

“Animal” system of representation is an appropriate name for this mechanism, since its function is to represent the objects on which animals must act so that their behavior can be guided spatially in relation to it. Since the object is represented by a system that is based on an interaction between the sensory input and behavioral output subsystems of the animal behavior guidance system, the animal system of representation is more than just a picture of the object. It gives the animal a conception of the object. The object is what its behavior is directed at, but if we set aside the specific goals it may have in regard to the object, it is represented in such a way that behavior can be guided in relation to it. And the conception is more complete, the more behavior is adapted to spatial aspects of the object, which depends on the animal’s level of neurological organization.

The simplest animal system of representation occurs in the “telesensory animal,” that is, animals that can perceive objects at a distance from their bodies. But the telesensory animal’s conception of the object is not a conception of the object as located in space, even though the object is typically located at a distance from the animal’s body and it guides locomotion in relation to the object. Though the object itself must be represented explicitly in order to determine its kind, its location is represented only implicitly in the instinctive routines by which the animal representation guides locomotion in relation to it.

The ability to think of the object as being located in space requires a conception of space. That is provided, as we shall see, by a faculty spatial imagination which enables the animal to think about the effects of locomotion (and motion generally) on the relations among objects in space. That occurs in subjective animals, and it is what I will call a conception of the object as located in space, because it enables them to see the object against the background of what is possible as a result of objects moving in space. (That is, spatial imagination uses sequences of images over time to represent the consequences of locomotion (and turning), and such sequences are the background in which objects are represented.) However, though the object may have a geometrical structure, the subjective animal does not have a conception of the object as having a geometrical structure. It has only the conception of the object as located in three dimensional space.

The ability to think about the object as having a geometrical structure requires a conception of geometrical structure. That is provided, as we shall see, by a faculty of structural imagination which enables the animal to think about the effects of manipulating the object on how it appears, how its structure changes, and how it relates to the geometrical structures of other objects in space. The actual geometrical structure is seen against the background of what is possible by manipulation (once again, by using sequences of images over time to represent the kinds of events that manipulation would cause). This new faculty occurs in what will be called manipulative animals, and since they already have a faculty of spatial imagination, it gives them a conception of the object in space as having a geometrical structure, for it can see the object against the background of what its geometrical structure makes possible.

Animal stages of evolution. Each way of these representations of the object serves the function of an animal system of representation more completely, but each depends on a higher level of neurological organization. These levels are the ontological cause of the animal stages of evolution, and each requires certain additional subsystems to serve their increasingly demanding functions. I will use their functions to introduce the animal stages of evolution. And the nature of somatosensory animals will be explained by contrast to all of them.

Somatosensory animals.Before considering what is required to serve the function of the animal system of representation, it should be emphasized that it is possible for animals not to have an animal system of representation. That is, even the object (not just its location) may be represented only implicitly in the animal behavior guidance system. In somatosensory animals, with the simplest animal behavior guidance systems, sensory input is still caused by the object, and, as always, sensory input is used to select the goal of animal behavior. But sensory input does not represent its cause as an object. At most, it might be said to represent the goal of the behavior it triggers, since it can select the kind of behavior. What serves the function of the system for representing the object is, in effect, the structure of the animal’s body.

In the somatosensory animal, it is contact with the object that guides animal behavior. In its decentralized nervous system, the object can be represented by a single somatosensory neuron, because its behavior is selected and generated by local connections between somatosensory input and motor neurons controlling nearby parts of the body. When contact reveals that the object is of the appropriate kind, behavior acts on the object at the location from which the input about its kind comes. It is a local reflex, though it may recruit appropriate behavior in other parts of the body. And reciprocally, similar reflexes in other parts of the body may trigger its motor neurons. But no centralized mechanism for guiding the behavior of the whole animal is needed. It is just what results from an equilibrium among many localized systems for guiding animal behavior.

Somatosensory animals include hydra, jellyfish, sea stars and brainless chordates (like Amphioxus). When an edible object brushes up against one of the hydra's tentacles, for example, it responds by stinging them and contracting. That reflex recruits other tentacles to contract as well, and thus, together, they pull the object contacted into its gastrovascular cavity. Sea stars also have locomotion, but it is guided locally, as each arm recruits the other arms (and its many little feet) to move in a certain direction because of the kinds of objects it contacts.

With only an implicit representation of the object, the somatosensory animal does not have a conception of the object. Though it responds according to the kind of object, no nervous mechanisms register input about its location in order to guide behavior in relation to it, because the object is always located where the sensory input is received and behavioral output is generated. Even less do somatosensory animals have a conception of the object as located in space, for it is the object’s location in space that causes it to be represented as an object at all.

Since the object need only be at a certain location to be represented as an object at all, it is the biological behavior guidance system that gives the animal its merely implicit representation of the object. Not surprisingly, therefore, this is also how behavior is “guided” to act on objects in animals at lower levels of biological organization, such as animal-like protists and bacteria. In paramecia, for example, the system for selecting whether to ingest objects or not is located in the oral groove where the object comes into contact with the animal. And the amoeba engulfs food particles wherever on its body they are encountered.

The most basic way that an animal system of representation makes animals more powerful than somatosensory animals is the ability to guide locomotion in relation to distant objects.

Though somatosensory animals may have locomotion, it is not guided in relation to distant objects in space, and thus, the geometrical structure they impose on the thermodynamic flow in the region is still short-range, channeling only the free energy of objects they happen to contact to fuel their reproductive cycles and avoiding only local hazards.

But when locomotion is guided in relation to distant object, what imposes a geometrical structure on the thermodynamics flow in the region is animal behavior itself, rather than merely the structure of the animal body. But guiding locomotion requires having a representation of the object that indicates its location relative to the body even when it is at some distance from the animals.

Sensory input from the distant object is obviously required for an animal representation of it. But in order to be useful in guiding locomotion, sensory input must be able to reveal its kind as well as its location. Unless the animal can also tell what kind of behavior to generate in relation to the object, guiding locomotion in relation to it will not control relevant conditions. In what follows, I will assume that the animal representation also indicates the kinds of distant objects as, not only their locations.

Telesensory animals. Telesensory animals are the simplest animals with an animal system of representation. The most obvious indication of their higher level of neurological organization is that their nervous system is centralized, whereas somatosensory animals have decentralized nervous systems. Centralization is required in order to guide behavior in relation to objects located at a distance from their bodies, because only groups of motor neurons can generate whole body behavior, such as swimming in fish or walking in land animals, and the same sensory input must control all of them. Sensory input also requires a higher level of neurological organization, because only groups of sensory neurons, as in the retina of the eye, can register effects of distant objects in a way that reveals information about their kinds and locations.

Sensory input from distant objects does not, by itself, contain enough information to guide locomotion in relation to it. In order to determine the object’s location, there must be an interaction between mechanisms serving the subfunctions of sensory input and behavioral output in the animal behavior guidance system. (Their interaction is also where we will find the higher level of neurological organization that gives animals spatial imagination, and the yet higher level that gives animals structural imagination.)

Sensory input from an object located at a distance from the animal, or “telesensory input,” can guide locomotion only when it is combined with input about the current condition of the animal’s body. For example, to use visual input to determine what is located in different directions, animals with eyes must take account of which way their heads or eyes are pointing when visual input is received, and that requires input about how the current condition of their eyes, head and body. I will call it input about the “bodily condition.” Thus, the animal representation of the object is telesensory input registered in a way that indicates the bodily condition. That is the animal’s “perception” of the object.

Since the animal must behave in various ways to gather information about what is located in each direction, perception generally involves a new kind of behavior. This holds of hearing and olfaction as well as vision. I will call it “inquisitive behavior,” in order to distinguish it from behavior directed at more basic goals, such as acquiring food, protection, mating and the like. Inquisitive behavior transforms telesensory input into feedback from its own motor output, making perception an active process. But whenever telesensory input from the object is registered in the nervous system according to the bodily condition at the time, it contains information that can be used to guide locomotion in attaining its goals with the object. This combination is an animal representation, because the animal can extract information from it about which way to move its body in order to change its spatial relation to the object appropriately. It is a perception of the object that implicitly contains information about its location.

Animal representations of objects also make it possible for telesensory input from an object at one time (when the object has one location relative to the animal), to be used in guiding the animal's behavior at another time (when the object has a different location relative to the animal). And in some telesensory animals, such as bees, so much information about the locations of objects in the surrounding space is recorded that their animal representations are implicitly maps of the relations of salient objects in their territories.

The basic structure of the animal system of representation can be seen by comparing the telesensory animal behavior guidance systems with that of the somatosensory animal. (See the accompanying diagrams of their animal behavior guidance systems.)

The animal behavior guidance system of somatosensory animals (and animals at lower biological levels) are so simple that their three subfunctions work together in the same way as the biological behavior guidance system (though they may be located throughout the animal body and recruit similar behavior in neighboring systems). Without an animal system of representation, they are unable to perceive objects at all.

In the telesensory animal behavior guidance system, what constitutes the animal system of representation is an interaction between mechanisms serving the sensory input and behavioral output subfunctions which is independent of the mechanisms serving the selection subfunction. An animal representation is constructed by combining telesensory input with input about the bodily condition. The bodily condition, such as which way the head and eyes are pointing, affects how telesensory input is registered, and how that input is registered is then used to determine how the animal moves, say, if it selects a goal that requires approaching the object. In telesensory animals, this mechanism is “hard wired” into the nervous system by the biological behavior guidance system in constructing it, and it is just a more or less elaborate set of rigid, instinctive routines that have been naturally selected for the power they afford.

The centralization of the nervous system is so obvious that no one denies the difference between "somatosensory" and "telesensory" nervous systems (though they many not use these terms). But the difference between them is not usually explained as a difference in level of neurological organization, and the main reason is that it is not recognized that there is a third level of neurological organization, much less a fourth. However, given that the function of the telesensory level of neurological organization is to provide an animal system of representation, however, we can see how higher levels of neurological organization could make animals even more powerful, including both spatio-temporal and structural imagination, because it is evident in the structure of their required subsystems. The following functional diagrams suggest their levels of part-whole complexity. These diagrams are explained more fully in relevant chapters, but even a gross impression of how they work shows how theses two higher levels of neurological organization would cause two step-like increases in animal power beyond telesensory animals..

Subjective animals.In subjective animals, the telesensory animal’s hard wired animal representation of the object is replaced by a kind of perception that is backed up by a faculty of imagination. The sensory input system still enables the animal to perceive the object in a way that guides locomotion in relation to it, but such perceptions are generated as part of a new interaction between the telesensory input and behavioral output systems, one in which covert locomotion in some direction can call up sequences of “local images” from memory representing the local scenes that would be encountered in moving in that direction (given a certain starting point).

What makes such spatial imagination possible is, as this diagram suggests, a higher level of neurological organization in both the sensory input and behavioral output subsystems. (The higher level is indicated by the two circles within the enlarged square, representing the necessary subsystems.) Telesensory images are recorded in memory in sequences according to the locomotion that connects them (with memory using its own input from the current bodily condition), so that they can be called up in sequences from memory. (Since they are sequences of images over time, they are labeled “spatio-temporal images.”)

Once spatial imagination has been set up in the brain, therefore, to perceive an object is to be able to imagine how its spatial relations to objects would change, if the animal were to move its body in relation to it. And to imagine what would happen if the object were to move relative to its body and other objects. That is the effect of covert locomotion on subjective memory. To see the local image (and the objects it includes) as located within the map of its territory is to perceive the object as located in space. It also means perceiving its body as located in space, as we shall see. The subjective animal has, therefore, a conception of an object as located in space.

Manipulative animals.In the manipulative animal behavior guidance system, the sensory input system is still the animal’s perception of the object as located in (and potentially moving in) mammalian space. But more is perceived, because sensory input also represents the object as having a geometrical structure. Within the subjective animal representation of the object as located in space (the object in the local image which is part of its map of the territory), there is a further interaction between the sensory input and behavioral output systems in which covert manipulation can call up sequences of telesensory (and tactile) images of objects as they would appear if they were manipulated in certain ways. That yields an object image in the local image.

What makes structural imagination possible is, as the diagram suggests, a yet higher level of neurological organization in both the sensory input and behavior output subsystems (as indicated by the circles within the circles within the enlarged squares). (The connections representing perception and input from the current bodily condition, which are the underlying structure of the animal system of representation connecting the sensory input and behavioral output systems) are suppressed in this diagram for simplicity.) In manipulative animals, telesensory images of objects are recorded in memory in sequences along with tactile images from the hands according to how the object is being manipulated at the time (with memory using its own input from the current bodily condition), and these images can be called up in sequences from memory. (Since they are sequences of images over time, they are labeled “structuro-temporal images.”)

Once structural imagination has been set up in the brain, therefore, to perceive an object in space is not only to be able to imagine what would happen if it (or its own body) were to move around in space, but also what would happen if its hands were to manipulate the object in some way (for example, how it would appear if turned upside down or backside forward). That is to perceive the object in space as having a geometrical structure. Manipulative animals have, therefore, a conception of the object in space as having a geometrical structure.

The functions of sensory input and behavioral output systems, of the new subsystems, and then yet newer sub-subsystems that come to exist within them suggest the way in which higher levels of neurological organization can be functional in the sense of opening up, step by step, entire, new ranges of possible powers that animal behavior might evolve.

Starting with the telesensory stage, one new stage actualizes the potential power of spatial imagination, and after that, another new stage actualizes the potential power of structural imagination. Animal power is increased in each case by making the spatial aspects of animal behavior depend on spatial aspect of the world. The spatial aspects of the world they are exploiting are ontologically basic. In one case it is an intuitive understanding of spatial causation, and in the other it is an intuitive understanding of structural causation. These faculties of imagination approach a natural perfection for neurological mechanisms of their kind as part of the natural perfection of the multicellular animals to whose power they contribute, but since such powers are useful only in some ecological niches, they become most powerful only in some species of multicellular animals.

In each of the following three sections (telesensory animals, subjective animals, and manipulative animals), the function, evolution and structure of the nervous systems at each of their three levels of part-whole complexity are discussed in detail. Since higher levels of neurological organization can evolve only after gradual evolution has made mechanisms on the lower level of neurological organization reliable, if not perfect, in serving their functions, each level of neurological organization entails a stage of animal evolution in time, just as each level of biological organization entailed a stage of biological evolution. These are the animal stages of evolution.

Somatosensory animals do not represent a distinct stage of animal evolution, because they do not evolve after the evolution of multicellular animals, but as part of it. Simply having a nervous system does not put somatosensory animals on a higher level of organization than other multicellular organisms, because it is just a variety of multicellular organism that fills a kind of ecological niche, namely, acquiring free energy ingesting energy-rich objects. The structure of the somatosensory nervous system is basically just the structure of the body constructed by the mechanism of embryological development, because all three subsystems of the animal behavior guidance system are served locally by three different kinds of neurons at each location in the body: sensory neurons (sensory input), interneurons (goal selection), and motor neurons (behavioral output).

A higher level of neurological organization is required, as we have seen, for the animal to have an animal system of representation at all, and even in telesensory animals, single neurons can no longer serve the basic functions of registering telesensory input and generating behavioral output. Each such subfunction requires a whole group of neurons working together. That puts telesensory animals on a higher level of neurological organization than somatosensory animals, and as the diagrams suggest, higher levels of neurological organization involve higher levels of part-whole complexity within the mechanism serving the same basic subfunctions, sensory input and behavioral output. As we shall see more clearly when we consider the structure of the brain, the basic functions of generating perceptions and using them to guide behavior depend on two yet higher levels of neurological organization: circuits of groups neurons in subjective animals, and interactions among several similar circuits of neurons in manipulative animals.

Most animals, from worms and insects to reptiles and birds, are at the telesensory level of neurological organization. But the animal stages of evolution are somewhat more complicated than the stages of biological evolution, because there are two forms of embryological development and, thus, two series of levels/stages in multicellular animals. And the difference is relevant, because their biological behavior guidance systems use basically different mechanisms to organize groups of neurons to act as a whole within the nervous system. One uses ganglia, and the other uses two dimensional arrays of neurons laid out in a special neural tube. As a result there are two basically different kinds of telesensory animals, and only one of them is able to evolve beyond the telesensory stage. Invertebrates never evolve a subjective behavior guidance system, and we must explain why.

The gradual evolution of embryological development.The evolution of the mechanism of embryological development is responsible for the most spectacular punctuation in the whole course of evolution, the Cambrian revolution at the very beginning of the fossil record some 600 million years ago, when many different species of multicellular animals suddenly showed up. Only when animals evolved hard parts, like shells, did fossils form, and the same mechanism that constructs such hard parts also constructs the nervous system.

Tracing the actual evolution of the mechanism of embryological development on earth should settle any doubts that may remain about the inevitability of the evolution of multicellular animals, because it shows concretely how such a mechanism lies within the range of variations on animal-like protists.

This rather technical history, however, serves an additional function in this ontological argument, because it leads to an explanation of the difference between proterostomes and deuterostomes (that is, between most invertebrate development and development in chordates, such as vertebrates and mammals). That will account for the radical difference between two groups of telesensory animals (invertebrates and vertebrates), and the nature of the difference between them will explain why proterostomes do not evolve to the third and fourth animal stages of evolution.

The origin of the mechanism of embryological development. Clues about the evolution of animals can be found by comparing how the various kinds of animals develop. The first steps in embryological development are least likely to have changed during evolution, for whatever the mechanism, variations in it would probably throw the whole process off track. Evolution occurs mostly by adding new structures to the process. And we can see how animals with nervous system began by identifying the first form of development. Let us compare the three basic forms of development.

Gastrulation. More complex animals, both proterostomes and deuterostomes, develop by a process of gastrulation. The fertilized egg cell is an unusually large cell, and asexual division produces many daughter cells (cleavage). They secrete a fluid in their midst and arrange themselves in a layer, enclosing it like the surface of a sphere. They are the blastula, and the cell-free area in their midst is the blastocoel.

Gastrulation follows the formation of the blastula. Its function is to establish a second layer of cells beneath the first. The cells destined to become the second layer, or endoderm, are one hemisphere of the blastula. With more energy-rich yolk from the cytoplasm of the egg, they are larger than the cells in the other hemisphere, which becomes the ectoderm. The second layer forms by a folding inward (invagination) that never breaks the surface of the sphere: At about the margin between the two hemispheres, cells on the surface of the blastula bend inward and start moving into the blastocoel, aligning themselves along the underside of the sphere's surface. Ultimately, about half the surface of the original sphere turns itself inside out to form the second layer of cells on the underside of the other half of the original sphere. But the resulting two-layered surface is not a hemisphere: The missing hemisphere shrinks to the size of a hole in the surface of a new, yet incomplete sphere. The hole, through which the endoderm has disappeared, is the blastopore, and the inner chamber, now lined with endoderm, is the archenteron. Finally, a second opening is made through the two layers of cells, forming a digestive tract between it and the blastopore. Differences that begin at the this point distinguish proterostomes from deuterostomes.liv (See diagram of Development in gastrulating animal.)

Planuloid development. Animals with nervous system could not have begun with gastrulation. The process involves such a complex coordination of the behaviors of so many different cells that it could not possibly have been the first step by which protists organized themselves multicellularly. Development occurs in another way in two classes of animals, flatworms and coelentrates. The two layers of cells are produced by a process, which I will call planuloid development.

A blastula still forms after the cleavage of the egg, but the second layer of cells is formed by the inward migration of cells, usually from all parts of the surface of the sphere. They clump together at the center of the sphere, separating themselves from the outer layer of the blastula, and then the outer surface of the inner clump makes contact with the outer sphere, or ectoderm. This is the planula. (See diagram of Planuloid development) The endoderm is formed by a split that starts at the center of the solid clump of cells and continues outward in one direction toward the ectoderm, where an opening is made for the mouth. The result is a gastrovascular cavity, rather than a digestive tract, for there is no second opening. The one opening is both mouth and anus. The cavity not only digests food but also circulates it to all parts of the body.

In coelentrates, such as the hydra, the gastrovascular sac develops long, hollow tentacles around the mouth which are used to paralyze prey and pull them into the mouth. But flatworms have a bilateral symmetry. The mouth opens from the middle of the body toward the ground, and instead of a radial symmetry around it, one of the directions becomes the longitudinal axis of the body, and the perpendicular direction has a bilateral symmetry.

Ectolecithal development. Coelentrates and flatworms, as we mentioned, are the simplest kinds of animals. But even their planuloid development is too complex to have been a variation on protists. After the solid core of cells has formed inside the blastula, and before the inner split has opened as a gastrovascular cavity, cilia grow from the ectoderm and the planula swims around for a while. But this early, pre-sexual stage of its life is surely not the first form that animals took, because it has no way of acquiring energy. It is still living from the energy reserves of the egg. The clue to the origin of multicellular animals can be found in a third kind of development which occurs only in certain kinds of flatworms.

The eggs of these flatworms develop in a medium of energy-rich yolk supplied from the outside by nurse cells (ectolecithal development). From the cells produced by the cleavage of the egg cell, first, the mouth (pharynx) forms. Attached to these cells, another group of cells forms a sac to receive what the mouth swallows; they are the primitive endoderm, or gut. The ectoderm is formed by a third group of cells that constructs an outer layer of cells in the yolk by stretching themselves out from the mouth through the yolk around the gut. The embryonic mouth then swallows the remaining yolk, which fills the gut, or gastrovascular cavity.lv (See diagram of Ectolecithal development.)

Ectolecithal development is unique. It occurs in just a few species of flatworms, but in no other animals. It would be difficult to explain why there is such an unusual kind of development unless it is the earliest condition. And it suggests how animals may have evolved.

The origin of ectolecithal development. The process of ectolecithal development requires only three kinds of cells, each with a distinctive kind of behavior. They can all behave at the same time, since no movement relative to one another in involved. Thus, this random variation would have required only a few cells (maybe as few as twelve). An amoeba's cycle of sexual reproduction could well have produced that many offspring at once. Assuming that it happened on some mechanism for determining its offspring to three different kinds of behavior, this lineage could have begun, if each kind of cell remained attached to one another and to at least one of the other kinds of cell in an asymmetrical way. By synchronizing the amoeboid contractions of the mouth cells, the group could trap and surround animal-like protists for digestion. The energy supplied by their ingested bodies would select a reproductive cycle of this kind, if it were possible at all.

A new source of energy is probably the only way that such an unlikely process could have been selected. It was probably not to consume plants, since a multicellular body is no better suited than single-celled animals. Nor is a multicellular body needed to ingest prokaryotes. They are on a lower level of biological organization and animal-like protists already feed on them. Thus, multicellular animals were probably selected in the first place as carnivores, which preyed upon larger animal-like protists that, before them, were at the top of the food chain. Once the means of constructing multicellular bodies had evolved, some variations would, of course, eventually evolve ways of using it to acquire energy by ingesting plants and prokaryotes.

This origin of animals would account for the ectolecithal development in primitive flatworms. It now occurs in eggs, where nurse cells supply the yolk, but at first, the offspring may have been constructed in the gut using the energy-rich molecules available there, making the gastrovascular cavity do double service as a womb. The biological behavior guidance system could select the behavior required for gestation as an extra stage in the behavior of reproduction by turning off the behavior involved in digestion. Amoeboid cells already have the capacity to contract and relax depending on the kind of object they encounter, and thus, the same cells could play the roles of both muscles and neurons in guiding the organism's behavior as a whole. Swallowing, for example, could be a contraction generated by a signal exchanged among the mouth cells when any member made contact with an animal-like protist. It could even have been an electromagnetic signal, like neurons, since cells of many kinds are responsive to them. Neurons would differentiate as variations of ectodermal cells that signalled cells to refrain from feeding in hazardous situations, for that would enable them to complete their reproductive cycles while others did not. That would explain why neurons always differentiate from the ectoderm, never from cells of any other kind.

Three basic kinds of cells. This explanation of the origin of animals with nervous systems depends on the capacity of offspring of a fertilized cell to differentiate into three different kinds of cells. The mechanism of differentiation lies in how the egg cell is prepared. By leaving different messenger proteins in different parts of the cortex or cytoplasm of the egg cell, cleavage gives different daughter cells different messenger proteins. The nucleus must enable the chromosomes to affect different parts of the cytoplasm in different ways, or else it could not set up the process involved in reproduction. Thus, the preparation of the egg cell would merely elaborate an existing mechanism. The messenger proteins would be keys for opening up certain special chromosomes, in addition to those used for ordinary housekeeping activities, thereby generating special kinds of behavior in them. And assuming the chromosomes are also opened up differently at subsequent stages of development, the differences would be permanent.

This way of determining the most basic differences among cells, which are responsible for the whole process of development, would be an elaboration of the protein mechanisms for handling the chromosomes, sorting them out, and forming a nucleus that were introduced with the evolution of eukaryotes. The mechanism by which sex is determined makes it clear that the nucleus handles different chromosomes in different ways.lvi Since this mechanism is so basic to the operation of the eukaryotic cell, evolutionary change would build on it by adding new steps or new kinds of behaviors to each of the basic cell kinds at each step. Nor could it change easily in the course of evolution.

Only three kinds of cells are needed to account for the process of development. They would differ from one another in how cells of the same kind remain attached to one another and how they relate to the other two kinds of cells. Cells that form the ectoderm must attach to one another on four sides as the 2-D surface of a sphere while orienting themselves to the mouth cells located among them. The inner gut cells must also attach to the mouth cells, but they would form themselves into a 3-D ball whose outer surface eventually attaches to the ectoderm. In addition to attaching to the other two kinds, the mouth cells would form an opening in the blastula. Behavior like this would require each cell to generate different kinds of behavior towards other cells on each side, but that is within the range of what eukaryotic cells can do, as the preparation of the egg cell and the asymmetrical structures of animal-like protists demonstrate.

A second kind of behavior is also required. Once they are attached to one another, the interactions of the different kinds of cells must set up the gradients of messenger molecules in which cells at different locations can be determined to different kinds of behavior, as in multicellular plants. It is not known how these gradients work, but we can think about what they must be doing by supposing that a gradient involves a pair of messenger proteins with one kind being concentrated at one extreme along its direction and the other being concentrated at the opposite extreme in that direction; their relative strength for any cell would indicate its location. One gradient would extend between the mouth cells and the other extreme of the blastula (oral and aboral poles). The mouth cells surely have a gradient around the opening that they form, which would give the blastula a gradient perpendicular to the first. And beside orienting themselves in the blastula and picking up its gradients, the inner-gut cells must have a gradient of its own that determines the center at which the split forms for a digestive cavity.

The evolution of other forms of development. The small scale and simple behavior required of such proto-flatworms, together with our explanation of the source of energy for development, makes it plausible that animals with nervous system originated from an amoeba whose offspring after mating included these three different kinds of cells. And it is easy to see how planuloid development and gastrulation could have evolved from it, thereby suggesting the basic evolutionary relationships among animals with nervous systems.

A simple rearrangement of the three kinds of behavior found in the primitive, ectolecithal development accounts for planuloid development: After cleavage, the ectodermal cells go to work, first, constructing the blastula in which the mouth cells have a location because of where the division of the egg cell has left them.lvii The gradients in the blastula are oriented around the mouth, and once the inner gut cells have migrated inward, formed a solid core, and made contact with the ectoderm, the split forming in their midst could be made to open up toward the mouth's location on the blastula by the gradients in the ectoderm. Thus, all the steps in planuloid development can be explained as a result of the interactions among the three original kinds of cells.

Gastrulation can likewise be explained as a modification of planuloid development in which one of the original three kinds of cells drops out of the process. Once again, the blastula is the result of the ectoderm-forming cells, and mouth-cells have a special location in it, establishing its gradients. But instead of cells migrating inward to form the inner core of cells, the second layer of cells is formed as a result of the behavior of the mouth-cells. That is, invagination can be explained as a variation on the behavior that makes an opening in the blastula and swallows. It is as if one half of the hemisphere swallowed the other half, turning the other half inside out to form a second layer of cells beneath the cells of the first half. Gastrulation results in a digestive tract with two ends. This could also be explained as a elaboration of the behavior of the mouth cells. After leading the invagination involved in gastrulation, the mouth cells eventually make contact with a special location on the blastula and form an opening by interacting with the ectodermal cells there. The clump-forming cells that supplied the endoderm for the planuloid animal have no role in forming the two layers of cells.

Embryological development is our best clue to the branchings of kinds of animals in evolution, and the implications of this account of the origin of multicellular animals with nervous systems can be made explicit by outlining the evolutionary tree to which it leads. We have found that the flatworms were the first multicellular animals. The original ectolecithal development evolved into the planuloid development of flatworms. And coelentrates and gastrulating animals both evolved from planuloid flatworms.

Gastrulating animals are of two kinds, proterostomes or deuterostomes, depending on the fate of the blastopore, the opening through which the mouth cells invaginate. In proterostomes, the blastopore becomes the mouth and the second opening becomes the anus, whereas in deuterostomes, the blastopore becomes and the anus and the second opening becomes the mouth. This is either an early branching among gastrulating animals or each evolved independently from the planuloid flatworm. And there is a second major difference between them, concerning how they form a mesodermal coelom, which suggests the fate of the third kind of cell found in the most primitive development that seemed to drop out with the evolution of gastrulation.

A mesodermal coelom is a cavity formed within a layer of cells that lies between the ectoderm and endoderm. It is the source of internal organs, including muscles, gonads, the circulatory system, excretory system, and the like. Only the more advanced proterostomes form a coelom at all. (Proboscis worms and round worms have no true coelom, although they do have a digestive tract.)

In proterostomes, it is constructed from a special pair of cells which were determined by how the cleavage of the egg divides up the egg cortex and cytoplasm. As a result of how the blastula is formed and gastrulation takes place, these cells wind up near the blastopore, which has become the mouth.lviii After gastrulation is complete and the anus is formed, one cell on each side of the blastopore migrates into the area between the ectoderm and endoderm, multiplies into a solid mass of cells, and a mesodermal coelom is formed by a split that starts in their midst. The process is called "schitzocoelous." The mesodermal cells are probably descendants of the third kind of cell from the primitive, ectolecithal development, which formed a solid clump of cells in which a split can develop. With their backs facing either the ectoderm or the endoderm, the fronts of these cells face a fluid-filled space formed by their splitting, and a 2-D gradient set up in it probably determines the cells at different locations to become different kinds of organs. The 2-D gradient in the ectoderm and endoderm enable them to locate themselves in the body. (See diagram of Schitzocoelous.)

Deuterostomes take a different tack, and as we shall see, it makes all the difference in their evolutionary destiny. The third kind of cell drops out again as gastrulation evolves from planuloid development. But the deuterostome forms a mesodermal coelom by enterocoelous, a continuation of the behavior of the mouth-cells that accounts for gastrulation. That is, after the endoderm invaginates, but before the mouth-cells make a second opening in the ectoderm (the animal's mouth, in this case), a second invagination takes place, this time from the endoderm into the blastocoel, the volume inside the original blastula that is now located between the endoderm and ectoderm.lix No cavity is formed by splitting in a solid core; deuterostomes make no use of the innerªgut cells from the primitive flatworm development. (See diagram of Enterocoelous.)

If this is indeed how animals with nervous systems evolved, then the primitive flatworm is their progenitor and all their kinds can be classified according to their modifications of its kind of embryological development. There are three branches. The simplest coelentrates have a larval stage that involves the planula. The other coelentrates and ctenophora have evolved from them, although some more advanced kinds have evolved a form of gastrulation on their own. Thus, these radial animals are one branch. On the second branch are proterostomes, and on the third are deuterostomes. Differences in how coeloms are formed accompany this defining contrast. As we shall see, this difference in embryological development explains the surprisingly radical differences between telesensory proterostomes and deuterostomes.

The proterostome nervous system development. Neurons always develop from the ectoderm. From the beginning, on our speculation, the chromosomes containing the genes that transform basic cells into neurons are opened up by the protein keys in the ectoderm-forming cells. But some additional factor must turn those genes on, since not all the cells of the ectoderm become neurons. The mechanism is not fully understood, but it apparently depends on gradients in the ectoderm. The cells becoming neurons can be evenly distributed over a regionlx or determined by singularities in the gradient. In the proterostome, gradients in the ectoderm (or the effect of special mesodermal cells on them) are responsible for cells becoming neurons.

More complex interconnections among neurons in proterostomes are made in structures, called "ganglia," which are located in various places in their bodies and connected by bundles of axons. In each ganglion, cell bodies are arranged on the outer surface, and its core is a neuropil where the processes synapse with one another. Axons of proterostome neurons branch near the cell body. One branch leads into the neuropil, and the other branch joins a nerve connecting to other ganglia or innervating muscles or sensory receptors at the periphery. Ganglia can develop when one or more cells that are determined to become neurons at some location multiply and form a cluster. When the cluster establishes its own gradient, their locations in it can determine neurons to become specific kinds as well as enable them to make quite precise connections with one another in each ganglion or between them.

The ganglia form in the ectoderm, and they must be interconnected to works as an animal behavior guidance system. The gradients of the ectoderm are used to connect neurons with one another as well as with sensory receptors on the input side and muscle cells on the output side. When cells become neurons, they develop processes, dendrites and axons, which extend out from the cell body and eventually form synapses with certain cells that they encounter. The axons are guided to other ganglia, muscles or sensory receptors as they form by following the ectodermal (or endodermal) gradients. Neurons at different locations in the body are thereby interconnected by nerves.

The typical structure of the proterostome nervous system is a set of ganglia in the ectoderm that are connected with one another and the ultimate inputs and outputs throughout the body. That is, the nervous system is laid out in the outer skin of the multicellular animal. The animal's behavior as a whole depends on the equilibrium reached by its entire nervous system, but that equilibrium depends, in turn, on the equilibria reached in each of the ganglia as they interact with one another by way of the nerves connecting them, given the sensory input from the rest of the body. We can see how the basic structure of the proterostome nervous system follows the gradients of the ectoderm by looking at the nervous systems of simpler animals, those with a planuloid development, because the gradients in the proterostome are simply how gastrulation has modified them.

The bodies and nervous systems of flatworms and coelentrates form from a larval stage called the planula, which as we have seen, is produced by the interaction of the three basic kinds of cells. The ectodermal gradients depend on the location of the mouth cells, and when the inner core of cells joins the ectoderm, it picks up the ectodermal gradients, enabling the split that forms in their midst to open up in the direction of the mouth. The mouth is the only opening, and body is a sac formed of two-layers of cells. There is a gradient between its oral and aboral poles and another gradient running around the body perpendicular to it. (See diagram of The planula.)

The body of the hydra, for example, is complete, once tentacles form around the mouth as elongated extensions of this gastrovascular cavity. Its nervous system is just a network of neurons differentiated at random in the gradients of its sac-like body, with a slightly higher concentration around the mouth. They are responsible for reflexes involving longitudinal muscles at the base of ectodermal cells and latitudinal muscles at the base of endodermal cells by which hydra's tentacles wrap around prey that swim by and pull their paralyzed bodies into its mouth. There is a second and maybe a third network of neurons which enable hydra to throw its tentacles out in various directions seeking prey and to somersault to more favorable situations by attaching its tentacles to the ground and throwing its body over them. But it lacks extroªsensory organs (like all coelentrates), getting by with somatosensory input and phototropisms.

The flatworm has essentially the same structure as the hydra, except that one of the gradients that is perpendicular to the oral-aboral axis is a longitudinal gradient for the body. That is, it has a bilateral body with its mouth located near the middle of its ventral side. The bilateral body enables it to move about in space head first, and the head has primitive telesensory organs to guide it: Pigmented eye spots detect the direction of light and the motion of object and lobes on the sides of its head with mechanoreceptors and chemoreceptors detect the direction of water flow and detect certain kinds of molecules in it. Like the hydra, the flatworm has a nerve net throughout its body which coordinates the body with the pharynx as it feeds, but superimposed on it is a second nervous system, which is organized like a ladder along the length of the dorsal side of its body. At least two, and sometime four, six or eight nerve chords run in parallel from head to tail, with regular latitudinal nerves connecting them and innervating the muscles of the body. At the head, there are ganglia where neurons from the sensory receptors intersect with the longitudinal nerves, which trigger or repress the reflexes by which it moves. Both nervous systems are laid out in the gradients of its simple body. The nerve net centered around the mouth generates feeding behavior, whereas the longitudinal, ladder-type nerves centered at the head generates locomotion. The balance between them presumably selects the kind of behavior. (See diagram of Flatworm.)

The basic structure of the proterostome nervous system can be seen as a transformation of the flatworm nervous system that result from the evolution of gastrulation from the flatworm's planuloid development. On our speculation, the second layer of cells is formed by the "mouth-cells," which are located at the oral extreme of the oral-aboral gradient in the blastula. The mouth-cells lead the invagination of one hemisphere of the blastula that forms a second layer of cells, but they do not stop there. The invaginating endoderm does not seek out the aboral pole of the blastula to locate the anus; instead, it seeks out the tail in the longitudinal gradient of the ectoderm. The blastopore, which becomes the mouth, is also shifted from the middle of the ventral side toward the head, shortening the ventral side anterior to the mouth. Thus, the original oral-aboral gradient in the endoderm coincides posterior to the mouth with the longitudinal gradient of the ectoderm. This produces a new framework of gradients in which the nervous system is laid out. The result is a nervous system composed of a pair of nerve chords running along the ventral side of the body with one pair of ganglia connecting them anterior to the mouth and at least another pair of ganglia posterior to the mouth. (See diagram of Proboscis worm.)

If this is how to understand the evolution of gastrulation form the planuloid development of flatworms, we can see how proterostomes are trapped into a nervous system with two pairs of ganglia encircling the mouth. One pair is anterior to the mouth, the other pair posterior, and connections between them encircle the mouth. Reproductive causation has never extricated the nervous system from the mouth in any proterostome. As our speculation suggests, the reason is that the biological behavior guidance system uses gradients in the ectoderm to determine cells as neurons and gastrulation has organized those gradients around the mouth. With bilateral bodies, nerves apparently cannot be differentiated along the length of the body except symmetrically, in pairs. Although the parallel nerves are sometimes fused through most of the body of higher proterostomes, at the head, they still lie on either side of the mouth and are reconnected anterior to it.lxi

This structure is clearest in the simplest proterostomes, proboscis worms (Nemertina) and round worms (Aschelminthes). In higher proterostomes, such as mollusks (clams and squid), annelids (segmented worms), and arthropods (crustaceans, spiders and insects), the mesodermal coelom gives the body a more complex structure. The mesodermal coelom superimposes a structure on the gradients of the ectoderm and endoderm, which may modify the structure of the nervous system, but it does not enable the nervous system to avoid having two pairs of ganglia encircling the mouth.

The most radical effect of the mesodermal coelom is the segmentation found in annelids and arthropods. It results from a special kind of division of the mesodermal cells. After migrating into the space between ectoderm and endoderm, they divide into many pairs of stem cells. Each pair marks off a segment in the ectoderm, and after forming a solid mass of cells, each clump splits and forms a coelom with a complement of organs. Each segment is roughly equivalent to a gastrula, and the series is chained together, mouth to anus, as a continuous digestive tract. The segmentation they impose on the gradient in the ectoderm affects the structure of the nervous system. In most segments, there are only two main ganglia, which are connected along the ventral side by a pair of (fused) nerves, as if the pair of ganglia anterior to the mouth in each segment were suppressed. But at the head, the anterior segment, where the nervous system is centralized, there are still two pair of ganglia encircling the mouth, with the telesensory organs supplying input to the anterior pair. Thus, segmentation does not enable proterostomes to escape the trap of having at least two pairs of ganglia encircling the mouth. A far more radical change is needed to escape the ectodermal gradients left by gastrulation.

The deuterostome nervous system development. Deuterostome development makes it possible to lay out a centralized nervous system without encircling the mouth. Neurons still differentiate from the ectoderm, but the ectoderm from which they differentiate is a region that has separated from the outer skin and rolled itself up as a neural tube which is contained as a unit inside the body. The structure of the nervous system can be laid out free of the gradients of the gastrula because the neural tube uses gradients of its own to determine neurons to different kinds and connect them with one another. Since the deuterostome's embryological development is what makes this possible, that is where we begin.

Deuterostome development. Like proterostomes, deuterostomes develop by gastrulation, rather than by forming a planula. After cleavage, the daughter cells arrange themselves as the surface of a fluid-filled sphere, called the blastula. A second layer of cells is formed as one hemisphere invaginates and lines itself up along the underside of the remaining spherical surface. The outer layer of cells is the ectoderm; the inner layer of cells is the endoderm; and the hole through which cells have invaginated is the blastopore. Deuterostome development differs from proterostome development because the blastopore becomes the anus and the second opening becomes the mouth -- which is just the opposite of proterostome development. The animal has a longitudinal axis running from mouth to anus, and properly speaking, the endoderm marks the boundary between body and world no less than the ectoderm, for it becomes the digestive tract (and respiratory system in higher chordates) by which the body interacts with other objects in space, albeit under conditions that are more easily controlled. (See diagram of Gastrulation in amphiouxus.)

The body's internal structure depends on the next step in the process, which is also differs radically from the proterostome. Its task is a twofold. On the one hand, it forms a third layer of cells, or mesoderm, between the ectoderm and endoderm, and on the other, it forms a neural tube just beneath the surface of the dorsal ectoderm. The third layer of cells includes not only the coelom, from which muscles, a circulatory system and various other organs develop, but also the notochord, which is the precursor of the spine. There is a symmetry abut these two developments because at the end of gastrulation, the segment of endoderm from which the chordamesoderm develops lies just beneath the neural plate, the section of ectoderm from which the neural tube forms.

The notochord and mesoderm are formed by enterocoelous, a process of out-pouching by the endoderm into the space between the endoderm and ectoderm, which was originally the blastocoel. The cells involved are the "mouth-cells" that led the process of gastrulation by invading the blastocoel in the first place, and thus, enterocoelous is just a continuation of the cell movements that took place in gastrulation. Gastrulation first began on the dorsal side of the blastula, and a section of endoderm that runs the whole length of the gastrula along the dorsal side is involved in the out-pouching. This surface of the endoderm bends in toward the adjacent ectoderm, forming two sections of cells, both of which break off from the endoderm, allowing the rest of the endoderm to close behind it, thereby restoring the surface of the archenteron. The out-pouching cells become the mesodermal coelom on one side of the body, and a notochord forms where they meet along the midline. In fact, these out-pouchings become a series of segments, for they are divided into segments, like the notochord, which run the length of the body. They eventually spread out to form a complete layer of cells between the ectoderm and the remaining endoderm around the sides and along ventral side of the body.

The nervous system is formed by a similar out-pouching, but this time from the ectoderm. The cells involved are a section of ectoderm, the neural plate, that runs the length of the dorsal side of the gastrula just above the medial chordamesoderm. The neural plate separates from the ectoderm and sinks beneath the ectoderm. As the ectoderm closes behind it, restoring the outer skin of the body, the neural plate rolls itself up into a tube in the space between the ectoderm and chordomesoderm along the entire length of the body.lxii (See diagram of Neurulation in amphiouxus.)

Ectodermal cells are determined to become part of the neural plate by the effect of the choradmesoderm on them during the process of gastrulation. And both the neural plate and chordamesoderm are segmented longitudinally in the process. That is, by the time the gastrula is formed, cells in different segments along the length of either structure have already been determined to become different kinds of cells. How this is accomplished is not known, but conceivably segmentation is induced by a pulse occurring during gastrulation that marks cells at regular intervals along its length as they invaginate. In any case, segmentation is a product of gastrulation, the process by which the "mouth-cells" form a second layer of cells in deuterostomes, not an effect of the special inner-gut cells from the primitive ectolecithal development, as in proterostomes. What is more, not only are cells located in different segments of the neural tube and mesodermal coeloms already different, but each segment has a 2-D gradient of its own in which cells can be differentiated.

The basic structure of the body at this stage is a set of tubes with the blastopore at one end and a mouth formed at the other. The outer tube is the ectoderm, and the innermost concentric tube is the endoderm. Filling the volume between them are several more tube-like structures: On the dorsal side is the hollow neural tube and just beneath it is the notochord. On each side of them lies a tube divided into a series of hollow areas, the coeloms. (See diagram of Crosssection of embryo of amphioxus.)

Although the segmented neural tube is the kind of basic structure that deuterostome development makes possible in the nervous system, it is of little use in the decentralized nervous systems at the somatosensory stage. There is a somatosensory deuterostome with a segmented neural tube, namely, Amphioxus, a cephalochordate. The sea squirt (a tunicate classified as an urochordate) also has a segmented neural tube at the larval stage. Even the rather primitive acorn worm (a hemichordate) has a neural tube, although it is not segmented.lxiii However, the neural tube is not a universal feature of deuterostomes. It is not found in echinoderms, such as the sea star. The sea star has a solid nerve ring to control the tube feet in each arm, and, like acorn worms, there is also a nerve plexus lying underneath the ectoderm over the entire body. The nerve plexus is an apparently haphazard network of neurons, and the neural tube seems to be just a section of such a plexus that has been rolled up into a tube during development in most kinds of deuterostomes, including all telesensory deuterostomes.lxiv

Independence of the nervous system. The most obvious advantage of separating the ectoderm from which the nervous system will develop from the outer skin is that it extricates the nervous system from the convoluted gradients of the ectoderm, which leaves proterostomes with two pair of ganglia surrounding the mouth. In the same way, it probably also enables reproductive causation to shape the body and its organs in whatever way that is useful in generating behavior without disrupting the nervous system, as it surely does in proterostomes with its ganglia and nerves running throughout the body. It also enables the nervous system to be divided into segments without the complete divisions of the body found in segmented proterostomes, since the segments are imprinted on chordamesoderm and neural tube by gastrulation, not by special mesodermal cells.

The unity that the neural tube gives the nervous system by contrast to the proterostome might well be compared to the contrast between the eukaryote and prokaryote behavior guidance systems. The prokaryote has a single loop of DNA attached to its cell wall, and the protein-DNA interaction that selects the kind of behavior occurs in the same space as the protein interactions that generate its behavior. In eukaryotes, DNA-protein interactions like those that guide prokaryotic behavior are contained within a nucleus, separate from the rest of the cell. Since its behavior is selected by an equilibrium involving an interaction of proteins and multiple chromosomes that is protected from interference by processes in the cytoplasm, eukaryotes can generate behavior on a higher scale than prokaryotes. Although the chordate is not on a higher level of natural organization from proterostomes, the neural tube, like the nucleus, does give the chordate nervous system a unity within the body that also enables it to generate behavior on an entirely new scale. Not only is the chordate nervous system not entangled with the organs generating the animal's behavior, but also when it is centralized at the second stages of zoological evolution, the processing required to select appropriate goals for the object and adjust its behavior to its spatial location can be carried out without interference by the rest of the body.

By separating the ectoderm which can differentiate into neurons from the rest of the body, the chordate has an additional step in setting up its nervous system: It must connect the nervous system to the sensory receptors and muscles in various parts of the body. The proterostome was spared this task by determining cells as neurons near the locations in the body where they would make their connections. But given the gradients that are established by gastrulation, it is a relatively simple task.

Although in Amphioxus, the connections between the neural tube and the body are made by processes from the neurons located in the neural tube, in the higher chordates, sensory cells (and neurons serving the viscera) derive from the neural crest. The neural crest is a group of cells that breaks away from the edge of the neural plate before it forms into a tube and individual cells migrate to locations in the body. In either case, the neurons that connect the neural tube with the body can easily find their targets. Not only does the ectoderm as a whole have a 2-D gradient of messenger molecules, but segments are also marked off in it by the segmentation of the mesodermal coelom. Given how segments are imprinted, mesodermal segments surely correspond to segments of the neural tube (and neural crest), enabling the same gradient mechanisms to be used in making connections at both ends. Neurons may even use the 2-D gradients set up within each mesodermal segment to locate the precise muscle or gland cells to which they will connect or to distribute their connections with internal organs evenly.

Neurons born in 2-D arrays. The advantages that a neural tube affords a centralized nervous system have been described negatively, as overcoming the deficiencies in proterostome nervous systems that derive from using the ectodermal gradients to lay out its structure. But positive advantages are what make higher levels of neurological organization possible. The 2-D gradient in which neurons can be determined to special kinds and make connections with one another are supplied by the neural tube. That is, since neurons are born with labels indicating their segment and 2-D location within that segment, there is no need for neurons to multiply and set up their own gradient to become neurons of specific kinds, as ganglia do.

Each gradient, we have assumed, involves a pair of messenger proteins, with one being concentrated at one extreme along its direction and the other being concentrated at the opposite extreme. The location of any cell in any gradient is indicated by their relative strength, and thus, the location of a cell in the neural tube is indicated by its location in two gradients: one in the longitudinal direction, and one that extends from the ventral midline of the neural tube to the dorsal midline where the two sides of the neural plate closed. Indeed, there are two sets of these 2-D gradients in the neural tube, since each half of the bilateral body would be a mirror image of the other. The third gradient, extending from the central canal of the neural tube to its outer border, is used to guide neurons in migrating and making connections, but not to determine neurons to specific kinds. Furthermore, since the neural tube is divided into segments along its length, the cells in each segment are different from those in other segments. And with each segment having its own 2-D gradient, it is easy to see how complex interconnections can be set up.

Suppose that once the gradients are established in each segment, each cell somehow records the relative strength of each pair of messenger proteins in which it finds itself. Some cells that are differentiated throughout the neural tube remain there; as they elongate, labels from the original gradient are posted, and these processes enable other cells to find their way about. They are called "glial" cells. At an earlier stage of development, cells of the neural tube are determined to become neurons. Neurons always divide at the inner surface of the neural tube bordering on the central canal.lxv When they send processes or migrate to other locations, they can easily line themselves up in a 2-D array with other cells from the same segment, because they can use the labels from their original locations in the neural tube to seek out the place where the balance between the messenger proteins of cells on one side is greater and on the opposite side less than their own. Or when processes arrive at another segment, they can superimpose themselves in a regular way on the cells already located there by seeking out their own location in the gradients of local cells. In short, entire 2-D arrays of neurons from one segment of the neural tube can be connected with 2-D arrays of neurons in other segments in a regular, topographical way. Indeed, that is what every neuron from a segment would do, unless they were differentiated from one another.lxvi

Vision is a good example of the advantage of the 2-D arrays built into the gradients of the neural tube. The retina of the eye derives in development from a section of the neural tube that migrates as a whole to the ectoderm and determines cells located there to become a lens and an eyeball surrounding it. The neural tube's gradients supply each neuron in the retina with information about its location in a two-dimensional matrix. Thus, their axons are able to keep their order as they project back to the neural tube. The optic nerve is a single cable, often containing millions of axons, and labels from their built-in gradients enable them to keep line up, even when the two optic nerves merge and the axons from half of each retina are sent off in a different direction. And they can easily superimpose themselves in an orderly way on 2-D arrays of neurons from other segments, which are their targets.

The contrast to the proterostome nervous system could not be starker. Cephalopods, such as squid and octopus, have camera-type eyes which are the equal of vertebrates, but their nervous systems is a collection of ganglia that are arranged around the mouth. The eyes feed sensory input to the optic lobes, which connect with other lobes, and behavior is guided by the equilibrium reached by an interaction that depends on the equilibria reached in each of various lobes. Visual input is conveyed by the configuration of firings in 2-D arrays of neurons, but in order to operate a camera-type eye, cephalopods must build up complex 2-D arrays of neurons within special ganglia in order to carry the information. A glance at the basket-weave of the optic nerve in the octopus makes it clear that a good part of the biological behavior guidance system's machinery for differentiating cells is used up simply keeping them straight as they project to the target. That is, a kind of structure that is very near the limit of what the proterostome development can accomplish is supplied by deuterostome development at the outset as the foundation on which further structure is constructed.

Although the somatosensory nervous system gets by with single neurons serving the functions of registering input, generating output and selecting between kinds of behavior, the telesensory nervous system requires at least one 2-D array of cells for vision and a centralized system to make use of it. Proterostomes and the chordates among deuterostomes are both capable of these two levels of natural organization in the nervous system. As I have mentioned, however, the third animal stage of evolution requires complete circuits of such 2-D arrays which can interact with one another as units to register input and generate output. The fourth animal stage involves the interaction between various channels through both input and output circuit of 2-D arrays. The machinery required to connect 2-D arrays of cells from ganglia is so complex that it is not possible for these mechanism to evolve as variations on the proterostome nervous system. But deuterostome development makes possible a neural tube that supplies labels to cells by which entire 2-D arrays of neurons are connected with relative ease. In chordates, therefore, a third level of neurological organization can occur as a variation on the second level, and a fourth level can occur as a variation on the third level. Given the possibility of higher levels of neurological organization, reproductive causation inevitably makes them actual. Thus, our interpretation of embryology gives us an explanation why a third and fourth stage of zoological evolution occurs in deuterostomes, but not in any proterostome.

5. Telesensory animals.Telesensory animals are multicellular animals with a centralized nervous system in which the three basic subfunctions of the animal behavior guidance system are served by entire systems of neurons. They include most invertebrates along with non-mammalian vertebrates, and after explaining why the basic structure of the invertebrate nervous system limits their subsequent evolution, this chapter describes the structure of the vertebrate brain in detail and traces the actual evolution of vertebrates on earth. But in order to deduce this stage of evolution, it must first be shown to be inevitable.

Inevitability of telesensory animals.According to this ontological explanation of evolution as a global regularity, the evolution of multicellular animals with nervous systems at the telesensory level of part-whole complexity is inevitable, if it is both possible and functional.

Possibility. To be possible, the telesensory level of neurological organization must fall within the range of random variations being tried out in the evolution of somatosensory animals. And it is clearly possible, because somatosensory animals already have already evolved the mechanism of embryological development to serve as their biological behavior guidance system, and they have already evolved neurons for transmitting and regulating the signals from sensory input that caused behavioral output. Thus, all that was required for telesensory animals to evolve was a higher level of part-whole complexity in the organization of the nervous system, that is, a centralized nervous system in which neurons are organized into systems that can serve the basic subfunctions of an animal behavior guidance system with an animal system of representation.

Neurons generating motor output must be parts of a single system, in order for animal behavior to include locomotion in relation to objects at a distance. But since local reflexes in somatosensory animals could already recruit one another to generate whole body behavior, control of locomotor behavior could be supplied by neurons that controlled all the local reflexes.

However, in order to guide locomotion relative to distant objects, sensory organism must be able to detect objects located at a distance from the body, and since that means using proximal input to extract information about distant objects, neurons must be organized on a higher level of part-whole complexity in space. There are only certain kinds of effects on the animal’s body that can be used: electromagnetic radiation, vibrations in the medium or substratum, and kinds of molecules encountered. But since somatosensory animals have already evolved neurons that respond to such effects, it is just a matter of organizing them into systems of neurons whose joint output depends on the distant objects causing the proximal input.

In the case of vision, for example, photo-sensitive neurons must be arranged in a two dimensional array (2 .D array). Not many such neurons are required for the compound eyes of insects, but in camera-like eyes. extremely large 2 .D arrays of neurons are required to register images focused on them by a lens. Hearing requires only neurons that are sensitive to mechanical disturbances, but to discriminate the direction and tone of the sound, they must compare the disturbances of many neurons at once. (Hearing evolve in vertebrates from the lateral line in fishes, which is basically a series of sensors of mechanical disturbances along the side of the body.) Though somatosensory animals already have cells sensitive to kinds of molecules (taste receptors) by which they choose which objects to ingest, olfaction requires a large variety of neurons testing many different aspects of the shapes of molecules at the same time. In each case, multiple neurons are organized as a whole system, and the effects of its geometrical structure are as important to the function of the telesensory organ as the kind of neuron of which it is composed.

These systems of neurons had to be organized as parts of centralized nervous system in order to use telesensory input to guide locomotion (and to select the appropriate kind of behavior as an animal behavior guidance system). And as we have seen, in order to construct an animal representation for guiding behavior in relations to distant objects, brain mechanisms must connect input from telesensory organs with input from their bodily condition, such as the orientation of the body and head and its locomotion. But since the mechanism of embryological development had evolved to construct structures of eukaryotic cells, there is no reason to doubt that the telesensory nervous system is possible.

Functionality. To be functional and begin another stage of evolution, however, such a higher level of neurological organization had to enable telesensory animals to control an entire range of relevant conditions that were out of reach for animals at previous stages.

Though it is clear that the ability to use telesensory input would make them more powerful than somatosensory animals, it may not be clear that this power was out of reach for all previous animals, because animals at lower biological levels move about and have mechanisms to guide their locomotion.

Magnetosomes in bacteria, for example, tell which direction to move in order avoid the toxic effects of oxygen-rich water near the surface. And animal-like protists, such Paramecia, have eye spots by which they can orient their motion relative to light.

However, even if this is the capacity to guide locomotion relative to distant objects, it would make telesensory animals inherently more powerful, because they would be guiding the locomotion of a multicellular animal, which is already inherently more powerful than single-celled animals.

In any case, these structures in animal-like protists are not telesensory organs, much less an animal systems of representation, because they do not detect objects at a distance in space. They merely orient locomotion in some ambient field. In these animals, locomotion is just a response to light built into the organism’s structure by the biological behavior guidance system, like reflexes in somatosensory animals.

Since telesensory animals are both possible and functional, this ontological explanation of revolutionary evolution implies that their evolution is inevitable. Telesensory animals would evolve on any planet in a spatiomaterial world like ours where stages of evolution could unfold at all. But since they begin another stage of evolution, reproductive causation also implies that their basic power to guide locomotion in relation to distant objects would evolve in ways that enable them to control additional conditions affecting reproduction. This prediction is confirmed by the main accomplishment of this animal stage of evolution, namely, the evolution of nervous systems with the capacity to map the relations of salient objects in their territory.

Maps. Telesensory animals would be even more powerful, if besides guiding locomotion in relation to objects currently being detected objects at a distance, their animal representations enabled them to guide locomotion in relation to currently undetected objects. Since telesensory nervous systems must already be able to generate more or less complex instinctive behavioral routines in relation to objects in space in order to generate the various kinds of behavior needed to control relevant conditions, only relatively modest modifications of their neurological mechanisms are needed to represent the locations of unperceived objects.

For example, the capacity to keep track of how far the animal moves in each direction relative to the sun or magnetic north would enable it to return to a nest by "dead reckoning" (so that once it is in the vicinity of its nest it could guide its locomotion relative to objects recognized from current telesensory input). Gallistel (1990) has marshaled abundant evidence of such mechanisms in telesensory animals. Desert ants, for example, find their way back to their hive by keeping track of how far they go in any direction relative to the sun or wind. Only when they get in what should be the vicinity of their hive do they orient their locomotion by telesensory input from objects in space. (Gallistel 1990, pp. 59-65.)

The use of large-scale maps by social insects like honey bees is undeniable. Returning foragers direct other members to energy sources by performing a figure-eight dance in relation to the azimuth of the sun that successfully communicates both the direction and distance to other bees. Gallistel shows how these feats could be explained rather simply, assuming that neural mechanisms can represent distances and directions of locomotion and perform quantitative computations on them.

Such telesensory level animal systems of representation are capable of rather sophisticated navigational feats. When honey bees, for example, are released in a region with a known bearing and distance from their hive, not only can they return to their hive, but they can also fly directly to another, unseen energy source with a different bearing and distance from their hive when they have recently been feeding on it and that is the only way to obtain energy (Gallistel 1990, pp. 131-140).

Such territorial maps suggest how much power can evolve in telesensory animals because their animal behavior guidance system contains a system of representation. But to call a mechanism a system of “representation” is to say that there is a correspondence between its representations and what they represent, and it is relevant to consider how such a correspondence is constituted by the animal system of representation, because it is the beginning of an explanation of the nature of truth that will hold of rational beings like us as well.

In the case of the simplest animal systems of representation, the correspondence is basically geometrical. Spatial aspects of behavior are adapted to spatial aspects of the world so that the behavior imposes a geometrical structure on the thermodynamic flow in the region, and what makes that possible is an implicit correspondence between the representation of the object in the animal system of representation and spatial aspects of the world. The representation of the object in the sensory input system has a geometrical structure that corresponds to the relations of objects in space because of how sensory input is recorded together with input from the current bodily condition.

Telesensory organs, like the eye, provide information about the locations and kinds of objects, not only because of the interaction between the eye’s geometrical structure and other objects in space (by way of photons), but also because that telesensory input is contingent on the direction in which the eye is pointing and the head is oriented. Telesensory input is registered in a way that reflects the bodily condition at the time, and since the animal representation can trigger behavioral dispositions that will approach or avoid objects at a distance, it can be used to guide locomotion in relation to them.

The basically geometrical nature of the correspondence between the animal representation and the locations of objects relative to the body solves a problem that functionalist explanations encounter when they try to explain correspondence with nothing but causal connections between input and output within the organism. The correspondence is not just a constant conjunction between telesensory input and the object in space that is involved in reference, as Fodor seems to mean by calling it a “casual connection,” but an isomorphism between a structure in the brain and the geometrical structures about the locations of objects in the space around the telesensory animal. (See Epistemological philosophy of causation: Rational causation: Psychology: Naturalism.)

In the case of maps of the spatial relations of unperceived objects in the territory, the correspondence depends on a more complex geometrical structure than is required to represent the locations of currently detected objects in space, because it involves two phases.

First, since the animal representation of the object functions as a map, telesensory input must be registered in a way that reflects how far the animal must go in certain directions relative to the sun or magnetic north to get from one recognizable location to another. (This is a form of inquisitive behavior.)

Once the map has been constructed, the animal can, during the second stage, use the isomorphism between those brain states and salient objects in the territory to guide its behavior in relation to undetected objects in space.

The construction and use of maps are two different structural global regularities generated by the structure of the nervous system. During the map-making phase, the nervous system acquires an additional geometrical structure from the world, and during the second phase, it uses that unchanging geometrical structure to guide its behavior. The world itself is, therefore, partly the source of the structural cause by which animal behavior imposes a geometrical structure on the thermodynamics flow of matter in the region toward evenly distributed heat. The use of its map enables the animal to anticipate what will happen as it moves in various directions so that it can choose among them according to the kind of behavior that would control relevant conditions. This geometrical fit of its behavior with the environment would be quite mysterious, except for the structural causes involved, including the first phase of map-making behavior that sets up the correspondence involved in representing the locations of salient objects in its territory.

The Inferiority of Invertebrates.The evolution of telesensory animals in the direction of natural perfection for organisms of their kind is necessary for the evolution of subjective animals, but it is not sufficient. The telesensory stage must make it possible for the mechanism of embryological development (the biological behavior guidance system for multicellular animals) to try out, as a random variation, the higher level of neurological organization required for locomotor imagination. Its possibility is clearly not a foregone conclusion. Indeed, it happened in only one kind of telesensory animal, the vertebrates. It did not happen in invertebrate animals.

It is because vertebrates seem so basically different from other animals that all the other animals are usually classified together as "invertebrates". It has long seemed that vertebrates have a greater capacity for evolution. They generally have larger and more powerful bodies, not only those that live in water, but also those on land and in the air. The closest invertebrates come to approximating the vertebrate animal system of representation are the octopus and squid, which have evolved the same kind of camera-type eyes (focusing images on a retina) that vertebrates of all kinds have.

However, many kinds of invertebrates, including insects, many mollusks, and even worms, are in the same category of natural kinds as sharks, fishes, amphibians, reptiles, birds and even dinosaurs. All are telesensory animals, with centralized nervous systems and the capacity to guide behavior in relation to objects at a distance. And map-making powers evolve in both classes of animals. Though the examples mentioned above are invertebrates, similar map-making capacities have been demonstrated in telesensory chordates, such as fish, reptiles and birds (Gallistel 1990, Chapters 4 and 5).

There is a similar difference between two classes of somatosensory animals, even those whose radial bodies indicate their adaptation at this level. There are simple somatosensory animals, which include the hydra, jellyfish, sea anemones and corals (coelenterates) and their somewhat more complex cousins, the comb jellies (ctenophora). But there is another kind of radially symmetrical animal that is far more complex, the echinoderms, including sea stars ("starfish") and sea urchins. The difference in their complexity does not come from their stage of evolution, since they are both kinds of somatosensory animals. (But it is explained, as we shall see, in the same way as the difference among telesensory animals.)

The difference in the fates of these two classes of animals poses a challenge to this ontological explanation of revolutionary evolution. If evolution is really a dialectic of gradual and revolutionary change in which stages of evolution follow one another in time, then why did the next stage not happen to any invertebrates species? Thus, let us consider what makes vertebrates so different from invertebrates before we show how the vertebrate nervous systems evolves a higher level of neurological organization.

The answer to this puzzle is found in their patterns of embryological development. There are basically two different ways that multicellular animals develop, and it has long been recognized as a basic difference among them. Once class has so-called “proterostome” development, whereas the other has “deuterostome” development. Deuterostome embryological development in vertebrates and how it differs from proterostome development will explain what makes it possible them to try out higher levels of neurological organization. The origin of this difference was explained, along with a more detailed description of the difference between proterostome and deuterostome nervous systems, in Stage 4: Origin of the mechanism of embryological development.

Since every cell in a (sexually reproducing) multicellular animal derives from the same fertilized egg cell and has the same genetic structure, the basic challenge in constructing a complex body or nervous system is to make the cells become different in their behavior and yet coordinate them so that they work together as a whole. This challenge has been met by a process called embryological development, which began with the original multicellular animals of this kind and became increasingly elaborate through evolution.

Sexual reproduction requires, as we have seen, that the whole body of the multicellular animal be constructed from a single fertilized egg cell, and this mechanism coordinates the lower level organisms of which multicellular animals are composed. This is a function of what is classified here as the "multicellular biological behavior guidance system."

The advent of that important mechanism is responsible for the Cambrian revolution, which marks the very beginning of the fossil record some 600 million years ago. That is when the fossils of many different species of multicellular animals suddenly showed up, and since fossils form only when multicellular animals evolved hard parts, like shells, it indicates roughly when the mechanism of embryological development first evolved. That is the mechanism that constructs the nervous system.

Cells are first determined to become different kinds by the part of the cytoplasm (or cortex) of the fertilized egg that they inherit from the initial divisions of the egg cell. But animals need complex bodies in order to act on other objects in space, and that requires a developmental process in which some cells (and groups of cells) move past other groups of cells that remain attached to one another. What made it possible for animals to have a form of embryological development that is so different from plants is the animal-like behavior of the protists from which animals evolved (presumably, amoebas), including locomotion. Except in the simplest animals, development involves a process of gastrulation, and early in that process, a major difference shows up among multicellular animals, indicating an early branching in the evolution of their kinds. It separates vertebrates from most kinds of invertebrates, and it explains why vertebrates are able to evolve higher levels of neurological development, beyond telesensory animals, whereas invertebrates cannot.

The major division among animals is the difference between proterostomes and deuterostomes. Most invertebrates are proterostomes, but vertebrates are deuterostomes. A brief sketch of the difference about the basic frameworks in which their nervous systems are laid out will make it clear why higher levels of neurological organization occur only in vertebrates.

In proterostomes, the basic structure produced by gastrulation is a single tube formed of two layers of cells (ectoderm and endoderm) stretching between the mouth and anus. There are apparently gradients of messenger proteins established in the tube as a whole, uniquely identifying every location in it. Although the mechanism has not yet been fully explained, the multicellular behavior guidance system can apparently address cells by their locations in this gradient, make them open up different segments of their chromosomes so they behave differently, and thereby enable them to move past other cells to other locations in the body which are also identified by this gradient. In proterostomes, this is the source of the structure of both the nervous system and most of the structure of the body. Neurons always develop only from the outer layer of cells in the tube (ectoderm). Cells located in certain parts of the two-layered tube are determined to become ganglia, which are clusters of neurons that set up their own gradients of messenger molecules among themselves. And the multicellular behavior guidance system can also use these new gradients, within the ganglia that form, to address cells individually and make them send axons to connect with certain other neurons in the same ganglion or to certain neurons in other ganglia located elsewhere in the body.

In deuterostomes, gastrulation is able to produce a basically different structure of gradients for the multicellular behavior guidance system to use in determining cells, although not all deuterostomes exploit this capacity. There is at least a 2-D gradient in the tube extending from mouth to anus identifying the locations of cells (with cells also orienting themselves orthagonally to the surface of the tube), and there is an additional body-length tube, the neural tube, with a similar 2 .D gradient of its own, which becomes the spinal chord and brain in vertebrates.

The neural tube is formed from a body-long strip of the outer layer of cells (or ectoderm) of the body-tube (or gastrula) which folds over and sinks beneath the outer layer of cells. Although neurons still develop only from the ectoderm, the ectoderm used in deuterostomes is the neural tube, and its separation from the rest of the body enables the multicellular behavior guidance system to use the 2-D gradients in the neural tube to address neurons separately from the cells that become other parts of the body.

Furthermore, during the process of gastrulation in which the neural tube is formed, both the body and the neural tube are segmented, so that there is actually a series of 2 .D gradients (including a difference between right and left sides of the body) running along the length of both the body and the neural tube. Thus, not only are all the cells of the behavior guidance system already separated from the rest of the body in a tube with their own 2 .D gradient, but that all .inclusive 2 .D gradient is also subdivided regularly into smaller 2 .D gradients. The animals that take advantage of deuterostome development to construct a nervous system in this way are all called "chordates".

Since the challenge to the mechanism of embryological development is to coordinate the behavior of lower level organisms, it is clearly an advantage to have a segmented neural tube in which to construct and operate the animal behavior guidance system separate from the rest of the body. Indeed, there is a useful analogy to the biological behavior guidance system. Chordates seem to have a higher level of organization than proterostomes in a way that resembles how eukaryotes differ from prokaryotes, although chordate and proterostome nervous systems are actually on the same level of part-whole complexity.

The prokaryote and eukaryote biological behavior guidance systems both coordinates the behavior of segments of DNA (or genes) in much the same way as the multicellular animal behavior guidance system coordinates the behavior of neurons in both proterostomes and chordates. The lower level organisms are coordinated by being parts of the structure of the organism as a whole. But prokaryotes are to eukaryotes as proterostomes are to chordates.

In prokaryotes, a loop of DNA, containing all the genes, is located alongside all the other molecules in the cell, whereas in eukaryotes, multiple chromosomes are kept separately in a nucleus, where the expression of all their genes can be coordinated without interference from the mechanisms generating the behavior of the cell as a whole.

Likewise, in the case of nervous systems. In proterostomes, neurons are determined to become ganglia from the body's 2 .D gradient alongside all the other organs of the body, whereas in chordates, the only cells that become neurons come from the 2 .D gradients of a segmented neural tube, so that the coordination of cells in setting up the nervous system is not disrupted by the coordination of cells in setting up in the body.

In both eukaryotic cells and chordates, there is a spatially distinct organ for controlling the simplest units involved in guiding behavior. It is important to recognize, however, that deuterostome development does not put chordates on a higher level of part-whole complexity than proterostomes. It does not make much sense to talk about levels of part-whole complexity when there are only two levels.

There is, moreover, a further advantage in separating the animal behavior guidance system in the neural tube from the rest of the body. In proterostomes, where there is no such separation, another set of gradients has to be set up in each ganglion to coordinate its neurons after the ganglion has been determined from the ectoderm. In chordates, by contrast, this step has already been accomplished before neurons are determined, because cells in the neural tube already contain labels indicating their relative locations in the local 2 .D gradient of each segment of neural tube as well as their segment relative to other segments in the neural tube as a whole. The chordate multicellular behavior guidance system can, therefore, address whole 2 .D arrays of cells in a segment at once and tell (some of) them (from each local area) to migrate to, or to send axons to, another 2 .D array in the neural tube, while keeping their relative positions in their own 2 .D structure and finding their counterparts in the target array. That is, chordates have 2 .D arrays located in a more inclusive 2 .D array. Thus, it is as if the units supplied by gastrulation for use in neural development were not just single neurons, but also whole 2 .D arrays of neurons.

This difference would explain why only vertebrates are able to try out yet higher levels of neurological organization, and we shall see why such connections among whole 2 .D arrays of neurons are essential to the mechanisms of the subjective animal system of representation that gives mammals a locomotor imagination. It will not be known precisely how the segmented neural tube gives vertebrates such an advantage until the mechanisms of the multicellular biological behavior guidance system are explained, but that is not essential to this argument, for it depends only on recognizing a basic difference between the biological behavior guidance systems of proterostomes and deuterostomes in how they coordinate the behavior of cells in setting up the structure of the nervous system.

The difference between a nervous system enclosed in a separate unit and one spread throughout the body is intuitively clear, and there are many reasons for believing that this accounts for the failure of invertebrates to evolve higher levels of neurological organization are not hard to find. Here are three (which are explained in more detail in Stage 4: Multicellular organisms: Evolution of embryological development).

First, it is clear that the gradients in the body of invertebrates could interfere with the structure of the nervous system, because, despite the obvious advantage to telesensory animals of having a nervous system centralized in the head for guiding locomotion, not a single proterostome has managed to disentangle its nervous system from the mouth itself. At the head of every telesensory proterostome, there are always two pairs of ganglia whose connections encircle the mouth. This reflects the gradients set up in the body by proterostome development, in which the mouth is the opening in the sphere created by gastrulation. Proterostome development is simpler than deuterostome, but it compromises the unity of the centralized nervous system.

Second, although proterostomes do develop segmentation in their bodily structures (in segmented worms and insects), it does not give the nervous system a larger 2 .D gradient in which smaller 2 .D gradients are embedded for use in connecting 2-D arrays at different locations with one another, because it is the body as a whole that is segmented. The body is, in effect, a series of simpler, proterostome bodies. Ganglia can be set up in each segment, but they still have to set up their own internal 2 .D gradients. Hence, they are independent of one another and not coordinated with one another by being embedded in a larger 2 .D gradient.

Unlike the deuterostome development of chordates, where the process of gastrulation segments both the body and the neural plate (which becomes neural tube), the segments in proterostomes are set up by the duplication of special mesodermal cells, which give rise to coeloms that divide the basic tube-like structure of their bodies.

Third, the evolution of a camera-type eyes in the squid and the octopus shows that the difference between invertebrates and vertebrates cannot be explained by any lack of ability to evolve the right kinds of cells. But the difference in their wiring does show the advantage of having 2 .D arrays built into the gradients of the neural tube. In vertebrates, the retina of the eye develops from a section of the neural tube that migrates as a whole to the ectoderm (where they determine cells located there to become a lens and an eyeball surrounding it). So their axons, with millions of them in a bundle, are able to keep their spatial relations to one another as they project back to the neural tube and superimpose themselves in an orderly way on the 2 .D arrays of their targets. But in order for the octopus, as an invertebrate, to operate a camera-type eye, the complex 2 .D array of cells must be constructed from the neurons in ganglia, and whatever is going on, a glance at the basket-weave structure of its optic nerve makes clear that it takes a good part of the multicellular biological behavior guidance system's capacity for determining cells simply to keep them straight as they project to their targets. Not surprisingly, it is not easy to combine many such neural mechanisms as parts of a larger neural mechanism. (See Diagram.)

By explaining why invertebrates are unable to try out higher levels of neurological organization, we also explain why vertebrates do. Deuterostome development coordinates lower level organisms in a way that can set up a segmented neural tube separate from the rest of the body so that it can then use all its powers of coordination to set up the nervous system and only later connect it with the body (using its parallel set of segmented 2-D gradients).

Vertebrates also differ from invertebrates, of course, in having generally larger and more powerful bodies. That has not been explained. Nor will we try to explain it, except to suggest that, since their size and power are mainly a matter of having an internal skeleton, rather than an external skeleton (as in insects) or no skeleton at all (as in the octopus), and since the vertebras are also determined as a separate unit running the whole length of the body (the notochord) in the same process of gastrulation and segmentation that determines the body and the neural tube (and the coelom, from which the internal organs come), it would not be surprising if the same cause were responsible for this other difference from invertebrates as well.

The structure of the non-mammalian vertebrate brain.In the non-mammalian vertebrate brain, the three systems serving the main subfunctions of the animal behavior guidance system are located in three anatomically distinct parts of vertebrate brains. It is relevant to take account of this structure, because shifting the sensory input and behavioral output systems to the part of the brain that served only the goal selection subfunction in non-mammalian vertebrates is the random variation that will try out the higher level of neurological organization found in the mammalian brain.

Basic structure. In the non-mammalian brain, the major systems and their functions are obvious, given the function of the animal behavior guidance system (and its three subfunctions). The brain itself is one of two main components of the nervous system set up in the neural tube.

The other component is the spinal chord. It is the entire nervous system of somatosensory chordates (represented by Amphioxus) from which vertebrates evolved. For vertebrates, the spinal chord serves mainly to connect the brain with the rest of the body.

In the brain's segment of the neural tube, embryological development results in three, anatomically distinct parts: just above (rostral to) the spinal chord is the hindbrain, followed by the midbrain, and finally (at the rostral-most end) the forebrain. These three units can be explained by the three subfunctions that any system that would choose among different kinds of behavior must have. Any behavior guidance system, as we have seen, must register input from the world, select from among incompatible kinds of behavior, and generate the kind of behavior chosen. That holds for the vertebrate brain. These three subfunctions account for the kinds of neural connections found in the hindbrain, midbrain and forebrain, as a brief sketch of their connections will confirm. (See the diagram of the main parts of the non-mammalian brain.)

Furthermore, the neural connections among these sub-systems are just what would be expected of an animal behavior guidance system with an animal system of representation, that is, with input from the bodily condition being combined with telesensory input to construct an animal representation of the object that can guide locomotion in relation to distant objects.

Hindbrain’s behavioral output system. The hindbrain is responsible for motor output to the body. In order to guide locomotion by telesensory input, the hindbrain takes over control of local reflexes in all segments of the original neural tube (as in Amphioxus), and thus, the somatosensory input that triggered those local reflexes is also passed toward the head (rostrally) and registered in the hindbrain. (See diagram of the behavioral output system.)

But the hindbrain does not represent the body somatotopically, that is, as a picture or isomorphic representation of the body. (Its diffuse organization is called a "reticular formation".)

There is, however, an appendage to the hindbrain, the cerebellum, whose neurons correspond roughly to the geometrical structure of the body because of how it assists in generating behavior. The somatotopic organization is required by the cerebellum's function. It modifies the hindbrain's motor output in order to even out the spatial distributions (and temporal sequences) of its ultimate commands to local muscle groups (using its own somatosensory input).

That is, when different regions of the hindbrain generating different kinds of behavior call on the same local muscle groups in the spine, the cerebellum distributes their orders spatially and temporally so that all the tasks requested are accomplished without overtaxing any local group (while keeping the body oriented in gravity, with the help of the vestibular nucleus). It has its own channel of sensory input from the body, from the inner ear about acceleration and orientation in gravity, and from nuclei (olivary nuclei in the caudal hindbrain) that appear to compare motor commands with somatosensory input. It modifies motor commands by way of its output to the hindbrain behavior generator.

Midbrain’s visual input system. The midbrain registers telesensory input from the object. The main form of telesensory input was originally vision, whose 2 .D arrays, as mentioned before, are easily set up in the neural tube. The retina is a segment of the forebrain that migrates to the ectoderm of the body and determines cells already located there to become a lens and an optic cup behind it. The retinal neurons send an ordered, 2 .D array of axons to a region of the midbrain called the "optic tectum" (and to a part of the forebrain called the "thalamus" from which the retina migrated). (See diagram of the visual input system.)

The optic tectum picks objects out from the background, a relatively easy task when either the object or the animal is moving. Its control of the direction of the eye serves the function of inquisitive behavior in the animal system of representation, though the optic tectum also receives some somatosensory input. But somatosensory input includes the "lateral line" in fishes, which can detect the pressure caused by fish swimming nearby, and there is also taste input to the optic tectum (from cranial nerves that serve the feeding apparatus), and hearing (after it evolves).

The optic tectum has a large projection to the hindbrain behavioral output system, by which the optic tectum can adjust locomotion according to the direction, motion and distance to the object in space it is tracking visually and direct routine responses to objects, as in feeding. In non-mammalian vertebrates, in short, the optic tectum serves as the animal representation, or the input subfunction in the animal system of representation, for it guides the locomotion of the body in relation to the currently perceived object.

Forebrain’s olfactory selection system. The basic need responsible for the evolution of the behavior guidance system is choosing the goal, and telesensory animals must choose which goal to pursue with respect to the object at a distance (feeding, self-protection, mating, and the like). This subfunction is served in non-mammalian vertebrates by the forebrain.

In the primitive vertebrate brain, these decisions depend mainly on the forebrain's own form of telesensory input, olfaction. The olfactory bulb, located at the extreme rostral end of the telencephalon, contains neurons that identify molecules by interacting with them directly. About organisms, olfaction is usually a reliable indicator of the kind being encountered. The olfactory bulb has multiple pathways by which it reaches the midbrain and can control the kind of behavior that the hindbrain generates in response to the visual input from the object. (See diagram of the olfactory selection system.)

One pathway by which the olfactory bulb affects the midbrain is through the hypothalamus, a (ventral) part of the diencephalon, which has multiple connections to the midbrain. A second pathway is through the amygdala, another nucleus in the telencephalon, which, as the seat of fear, can override other routines and generate fighting or fleeing instead. And there is a third pathway involving the septum, a ventral part of the telencephalon.

In primitive vertebrates, the main route for affecting the midbrain is via the habenulae, a prominent, asymmetric pair of nuclei located just above the diencephalon (or atop the dorsal thalamus) which has a heavily myelinated bundle of fibers (the fasciculus retroflexus) that passes through the thalamus to a spiral shaped nucleus at the ventral midline of the midbrain (the interpeduncular nucleus). The olfactory bulb projects to the hypothalamus and the septum (which are interconnected), and they have connections to the habenulae via the stria medularis. The amygdala (which is also connected to the hypothalamus) has a connection of its own to the habenulae via the stria terminalis. (See diagram of the olfactory selection system.)

The forebrain also has, as we shall see, two other ways of affecting motor output, which depend on other kinds of sensory input. The forebrain receives (via its thalamus) visual input (both indirectly, by way of the optic tectum, and directly, from the retina), auditory input (after hearing evolves), and even some somatosensory input, all of which become increasingly pronounced in the evolution of vertebrates. (See diagrams of the forebrain output.) But these sensory inputs are used only to modify behavior in relation to distant objects currently being detected by the optic tectum and to generate complex instinctive routines, including telesensory map-making routines. Thus, there are, including olfaction, three ways that the forebrain can influence what happens in the midbrain and hindbrain, and all have to do with the subfunction of selecting the right kind of behavior.

Foundation for a higher level of neurological organization. Looking ahead, the transformation of the non-mammalian into the mammalian brain is often described as the centralization of functions in the nervous system. That is, as mentioned above, the three subfunctions of the animal behavior guidance system, which are parceled out to the three anatomically distinct sections of the non-mammalian brain, are all served by one of those sections in mammalian brains, namely, by the forebrain. The midbrain and hindbrain structures are still there, but they are slaves to the forebrain. The simplest and most convincing way to show how the four subsystems of the subjective animal system of representation are the functions served by structures in the mammalian forebrain will be to describe how those structures evolve from simpler mechanisms in the non-mammalian forebrain, and thus, it will be helpful to describe the relevant structures of the vertebrate brain here.

There are two important kinds of changes in the mammalian brain, not only the evolution of a neocortex, but also the redirection of erstwhile forebrain output back to the forebrain (by way of the thalamus) to form the complete circuits of its higher level of neurological organization. To see what is involved in these changes, let us look at the structure of the non-mammalian forebrain more closely and its three outputs to the midbrain.

Embryological development of the forebrain. The vertebrate forebrain develops from the extreme rostral section of the neural tube. It has two parts, the diencephalon and telencephalon. (See earlier diagram of the main parts of the non-mammalian brain.)

The diencephalon is the neural tube itself at that most rostral section. It is divided into two parts: the dorsal half, the thalamus, receives and passes on to the telencephalon all the forebrain's sensory input, and the ventral half, the hypothalamus, is the master control of the endocrine system (managing the messenger proteins, or hormones, in the blood) and the parasympathetic nervous system (sending nerves to internal organs). (The hypothalamus is, therefore, the main way in which the outputs of the animal behavior guidance system and the biological behavior guidance system are coordinated.)

The telencephalon develops from the same segment of the neural tube as the diencephalon. That segment of the neural plate does not close fully into a tube like the rest of the nervous system; instead, both sides are extended and thickened and become two, symmetrical flaps, which ultimately almost surround the diencephalon, as the telencephalon.

Forebrain output to the midbrain. The non-mammalian forebrain projects all its output to the midbrain, because that is where the optic tectum uses telesensory input to guide the locomotion in relation to the distant object (that is, where the animal representation of the object guides locomotion). The default behavior is normal locomotion and feeding. (Taste receptors have direct connections that affect feeding behavior.) Output from the forebrain modifies these behaviors and is responsible for selecting most other goals. The forebrain's outputs are all received by a region of the midbrain where the optic tectum influences the hindbrain motor commands and determines how the body moves in relation to the distant objects, approaching or avoiding them.

The most primitive output of the non-mammalian forebrain to the midbrain for choosing the goals of the behavior has already been mentioned. It originates from input to the olfactory bulb and reaches the midbrain by various ancient pathways, including some through the hypothalamus. This, together with another olfactory pathway (through the amygdala, a ventral part of the telencephalon), becomes the affective system in mammals.

It is the two other ways that non-mammalian forebrains can influence behavior that are relevant to the evolution of the subjective system of representation itself. Both of these other two outputs depend on visual, auditory or somatosensory input received by the thalamus and relayed to the telencephalon. But each involves a different target in the forebrain. One target is the (non-mammalian) dorsal cortex, the extended flap that develops from the neural tube at the diencephalon into the telencephalon, and the other is the striatum, a structure at the base of that extended flap. The dorsal cortex sends output to the midbrain by way of its connections to the extreme (medial) edge of the flap, which is (or becomes) the hippocampus. And the hippocampus projects, in turn, (by way of the fornix) to the hypothalamus, which sends output to the midbrain and to the mammillary body located in the hypothalamus. (The mammillary body has its own projection to the midbrain.) (See diagram of the hippocampal and striatal two pathway for forebrain output.)

The striatum, the other forebrain target, sends output to the midbrain by way of connections in and through the hypothalamus. (See diagram of the hippocampal and striatal two pathway for forebrain output.)

The size of the forebrain increases in vertebrate evolution, and the size and definition of the striatal and hippocampal pathways to the midbrain increase more than that of the primitive olfactory pathways. But the function of striatal and hippocampal output to the midbrain is basically to select the right kind of behavior for the distant object, including the construction of instinctive telesensory maps. They generate instinctive responses, including complex fixed action patterns, by modifying behavior that is already being adjusted to the currently detected distant object by the optic tectum in the midbrain.

For example, in an amphibian like the frog, visual input from the retina and optic tectum that is relayed (by the thalamus) to the striatum is used to select flight from large objects that are moving toward them (which are usually predators), suppressing their normal behavior of snapping at food. And visual input from the retina relayed (by the thalamus and dorsal cortex) to the hippocampus is used to keep frogs from jumping into walls. (See Macphail 1982 on amphibians and reptiles.)

In birds, at least, this hippocampal pathway evolved into a complete circuit for a one-dimensional, vision-based memory for retracing a pathway of salient landmarks, which approximates the mammalian memory circuit.

In the avian brain, the dorsal cortex contains a detailed visual image called the "visual Wulst" which controls locomotion by its own, direct motor output. It is part of a memory map that uses visual input relayed by the thalamus directly from the retina to the dorsal cortex. And as part of the dorsal cortex, the Wulst connects through the medial cortex/hippocampus and fornix back to the mammillary body in the hypothalamus. But instead of merely influencing the midbrain and motor output, as in other non-mammals, the mammillary body relays a signal, by way of the thalamus, back to the Wulst in the telencephalon. This is a complete circuit, resembling the mammalian memory mechanism, is apparently used to construct a memory map for guiding locomotion. Assuming it works the same way as in mammals, the Wulst can use a one-dimensional chain of stimulus-response connections as a map to guide locomotion without involving the rest of the circuit (hippocampus, fornix and mammillary body). But vision is the only sensory modality involved, and judging by the neurological mechanisms, it cannot use its memory map as a locomotor imagination.

Reptilian innovations. There is little change in the basic structure of the non-mammalian vertebrate brain (after the evolution of the jaw in fishes), except for three important changes, each involving one main parts of the brain, that came with the evolution of reptiles and the their use of legs to support the body.

Legs that could support the body made vertebrates better able to move across land, and new mechanisms were required to operate them. A new section of the cerebellum (the paleocerebellum) was required to balance the body on its legs and smooth out motor commands to them. And to serve this function, it has a somatotopic organization, that is, like a picture of the body.

The paleocerebellum projects to a new nucleus in the midbrain, the red nucleus, which uses a somatotopic array of neurons to send motor commands to the limbs.

Finally, the source of the more complex motor commands required to operate legs is a prominent, new structure in the telencephalon, the DVR (dorsal ventricular ridge). It is a major modification of the striatal pathway of forebrain output, because the DVR receives most of the thalamic relay of sensory input via this pathway to the telencephalon (including both the direct and the indirect visual channels), and the DVR projects to the striatum, by way of which its output reaches the midbrain and hindbrain areas for generating motor output. The DVR controls the motor commands from the red nucleus by way of a projection from the hindbrain to the paleocerebellum. (The main part of the DVR also projects to a more basal part of the DVR, which also receives olfactory input and projects to the hypothalamus, according to Ulinski, 1983.) (See diagram of the reptilian brain with paleocerebellum, red nucleus and DVR.)

To sum up, there are only three ways that the non-mammalian forebrain can affect the behavior being generated in relation to the distant object by the midbrain and hindbrain: the ancient olfactory pathway, the hippocampal pathway, and the striatal pathway. And the only input to the non-mammalian forebrain is the sensory input (indirectly from the midbrain and directly from the retina) registered in the thalamus of its diencephalon and relayed to various structures in the telencephalon — that is, except for the forebrain's own telesensory input, olfaction, and what the hypothalamus gathers from its control of the endocrine and parasympathetic nervous system. Although there is, as we have seen, a further development of the reptilian brain in birds, this is the basic structure of the reptilian forebrain from which the subjective animal system of representation evolves.

The gradual evolution of vertebrates.In the first section of this chapter, we found that the evolution of telesensory from somatosensory animals is inevitable because it is both possible and functional. In the second section, we saw how deuterostome development of chordates makes it easier to construct a nervous system with a telesensory level of part-whole complexity, and the third section described in detail the structures in the vertebrate brain that are the foundation for using the deuterostome capacity to determine entire 2-D arrays of neurons to construct a brain with yet higher level of part-whole complexity. We are following the inevitable stages of evolution that lead up to beings like us, and thus, it remains only to trace the gradual evolution of telesensory animals on earth. We may set aside animals with proterostome embryological development, because we have sufficient reason to believe that they are not capable of evolving beyond the telesensory stage. Let us consider briefly, therefore, the origin and evolutionary career of vertebrates, beginning with the somatosensory animals from which they evolved.

Somatosensory chordates. We are counting somatosensory animals as a necessary part of the multicellular biological stage of evolution, because we want to count how many distinct levels of part-whole complexity and, thus, how many distinct evolutionary stages, there are in the ladder that begins with the original proto-organisms and ascend to beings like us. The multicellular animals from which vertebrates evolved are somatosensory chordates, and they are represented by the brainless chordate, Amphioxus.

Without a brain, its nervous system is equivalent to the vertebrate's spinal chord. Relatively sophisticated swimming behavior is generated in its bilateral body by local connections between segments of its neural tube, each with sensory, motor and interneurons serving the three basic subfunctions of somatosensory animal behavior guidance systems. The function of selecting the right kind of behavior is served by a cough reflex at the mouth that rejects unwanted particles. And motor reflexes triggered by somatosensory input lead Amphioxus to burrow into sand at the edges oceans around the world in order to feed on microorganisms and protect itself.

Before vertebrates evolved, brainless chordates must have acquired free energy in more active ways than Amphioxus, feeding on microorganisms while swimming or seeking out multicellular plants to browse on. It is not known how vertebrates evolved from animals like Amphioxus, except that it was part of the evolution of telesensory organs. But it is no surprise that Amphioxus is the only extant representative of the first stage, because when chordates did evolve telesensory organs and a centralized nervous system to use them in guiding locomotion, somatosensory chordates were left with only the most low-energy, sedentary ecological niches.

Telesensory chordates (Vertebrates). According to the detailed fossil record, which begins with the Cambrian Period about 570 million years ago, vertebrates showed up about 500 million years ago, after almost every kind of marine invertebrate had already evolved.

Multicellular plants had evolved long before the Cambrian period, and what accounts for the fossils of animal skeleton that mark the beginning of that period is the evolution of the mechanism of embryological development (that is, the biological behavior guidance system for multicellular animals). The relatively late arrival of chordates suggests that deuterostome development evolved after proterostome development.

Vertebrates are named after the series of vertebra that enclose their neural tube, except at the head, where the brain is located. From the beginning, as we have seen, the vertebrate brain had three, anatomically distinct parts (midbrain, forebrain and hindbrain), serving, respectively, the three subfunctions of the animal behavior guidance system (input, choice and output), and we have seen how the function of the telesensory animal system of representation is served by its structure. There is remarkably little change in the structure of the non-mammalian brain, but the bodies of non-mammalian vertebrates underwent radical changes.

The most primitive vertebrates, jawless fishes (Agnathia), were still filter feeders. They actively scooped up detritus from the bottom, although their contemporary descendants, lampreys, have adapted the jawless mouth for preying on other fish.

From them evolved the now extinct, heavily armored placodermi, with a major reorganization of the hindbrain to operate its hinged jaw. The jaw not only made them ferocious predators, but also revolutionized the means of ingesting other organisms for all subsequent vertebrates.

Two kinds of fishes evolved from placodermi, cartilaginous (such as, sharks and rays) and bony. The cartilaginous skeleton was a departure from the bony frames of placodermi and jawless fishes. But bony fishes were so successful that there may now be as many as 40,000 species of them. The earliest of them were fresh water fishes, which had lungs as well as gills to supplement their supply of oxygen when the water was stagnant. In most extant species, the lungs have evolved into a swim bladder, which is also used for water-borne hearing. But one early lung fishes, the lobe-fin fishes (Crossopterygii), had fleshy bases for their two pairs of fins.

From lung fishes evolved amphibians. Their ability to pull themselves across the land opened up a new range of living objects to ingest, for by this time, plants and some insects had already invaded the land. (They were our first example of gradual evolution by reproductive causation, in Change: As aspect of substance: Global regularites: Reproductive: Gradual evolution).

There was room for improvement among vertebrates that completed cycles of reproduction on land. Although fertilization is still an external, water-based process in amphibians, it was done internally by reptiles. Reptiles not only had eggs with a shell that protected them from drying out as the embryos developed on land, but the reptilian body also acquired a dry, scaly, relatively impermeable skin. There were also advances in the heart and lungs. And whereas amphibians had short, weak limbs attached high on the sides of their bodies, reptiles evolved longer and stronger limbs that push directly downward, enabling their bodies to clear the land as they moved along. In order to operate these limbs, new structures evolved within the basic three-part structure of the vertebrate brain to send different motor commands to different legs (the paleocerebellum in the hindbrain, the red nucleus in the midbrain, and the DVR in the forebrain) . Reptiles also have air-born hearing, which among amphibians, occurs only in frogs.

Dinosaurs and birds evolved from reptiles. Dinosaurs were apparently able to move around very quickly on two legs, freeing their front legs to grasp other living objects; only as larger dinosaur species evolved did some return to four-footed locomotion. Dinosaurs may have evolved some control over bodily temperature, but we have little evidence apart from birds, which descend from an early dinosaur species. Hollow bones and feathers adapted birds to flight, and besides improvements in heart and lungs, they acquired the metabolism to maintain a high body temperature. Since hatchlings cannot acquire energy for themselves until their bodies have developed far enough to fly, birds also care for their young, a rather rare trait before the evolution of mammals. Birds also have, as we have mentioned, a one-dimensional, stimulus-response, vision-based memory for retracing a pathway, as in returning to a nest, patrolling a territory, or migrating with the seasons, and dinosaurs probably did too.

Although these changes in vertebrates required enormous periods of time, they are all at the same stage of animal evolution. Jawless fishes first appeared about 500 million years ago, about 70 million years after the start of the Cambrian period. The jaw evolved somewhat more than 400 million years ago, about the time that plants invaded the land. Amphibians evolved from the lobe-fined lung fish a little more than 350 million years ago, during the age of fishes. Reptiles evolved about 300 million years ago, late in the age of amphibians, and the dinosaurs evolved about 225 million years ago, after the decline of amphibians, followed shortly by birds (over 200 million years ago). The evolution from fishes to amphibians to reptiles to dinosaurs to birds is not a result of the dialectic of gradual and revolutionary change, because their nervous systems (and bodies) are on the same level of part-whole complexity. They are just a series of adaptations of an animal behavior guidance system with a telesensory animal system of representation (and the body it operates) to new habitats on land and in the air (though some used their improved design to return to water). These changes did not alter radically the structures of their brains.

6 Subjective stage. Subjective animals are multicellular animals with a higher level of neurological organization than telesensory animals. They are all mammals. We will see why mammals are inevitable and trace their gradual evolution. But as a result of explaining the mechanisms built into their higher level brains, we will also understand why there is a unity to the consciousness of mammals like us, finally repaying in full one of the four mortgages we took out to use spatiomaterialism as the ontological foundation for this argument.

The inevitability of an evolutionary stage following the evolution of telesensory animals depends, according to this ontological explanation of revolutionary change in evolution, on a higher level of neurological organization being both possible and functional. We have found good reason to doubt that such a higher level of neurological organization is possible in invertebrates. Their kind of embryological development is not able to try out the radical random variation required to organize neurons on a higher level of part-whole complexity. Or to put it positively, the main reason that such a radical random variation is possible in vertebrates is that their kind of embryological development is able to determine the fates of entire 2-D arrays of neurons as ordered units. That makes it relatively easy to organize such systems of neurons as parts of larger, complete circuits in the process of embryological development.

The mechanism of embryological development is, however, only part of the explanation of the possibility of mammals. Its possibility also depends on the way in which the more detailed structure of brains with the subjective level of neurological organization can be acquired from the structure of the world, that is, by learning from experience. Such learning is, as we shall see, a later phase in the process of neurological development in subjective animals, a stage during which detailed nervous structures evolve within the individual brain through natural selection by reinforcement (that is, as a form of evolution by reproductive causation that occurs within the mammalian brain).

If a further reason is needed for believing that the subjective level of neurological organization is possible, it will be found in following the actual evolution of nervous structures in the mammalian brain from the structures that were identified in the vertebrate brain in our discussion of the previous stage, stage 5. That is another way of proving that the structures to be identified in the mammalian brain actually have the functions that I will ascribe to them.

Both of these further reasons for believing in the possibility of the subjective level of neurological organization depend, however, on its function, that is, on how it opens up an entire, new range of powers that can evolve for controlling relevant conditions. Though I have already said that its function is to give animals spatial imagination, the time has come to explain what is meant by such a faculty of imagination and to describe functionally the systems and subsystems of the animal behavior guidance system that would give animals such a cognitive power. That is where we begin.

Function of the subjective level of neurological organization.Since animal behavior acts on other objects in space, its power can be increased, as we have seen, by adapting the behavior to spatial aspects of the situation in which the animal must act. That makes animals better able to control the conditions affecting their reproduction. One of those aspects is the way that the structure of the space, by helping to constitute what happens in the region, imposes regularities on how such objects can change location and interact with one another, or what I have called spatial causation (including how it helps cause local regularities ontologically as well as global). That aspect is, perhaps, better described as a spatio-temporal aspect of the situation, since it includes regularities about change. In any case, taking advantage of it in guiding their behavior to act on other objects in space is the basic function of spatial imagination. The function of the subjective neurological level is, in short, to understand spatial causation.

Spatial imagination. In order to show that such a faculty of spatial imagination would make animals inherently more powerful than telesensory animals, let us recall the cognitive powers of telesensory animals. Not only do telesensory animals have the capacity to guide behavior in relation to objects that can currently be perceived, but they also have the capacity to construct a map of the territory by which they can guide behavior in relation to objects that are not currently perceived.

The territorial map used by telesensory animals, such as bees and birds, is basically, however, just an elaboration of the complex instincts that have evolved in relation to the telesensory representations for detecting of kinds of objects in order to choose which of incompatible kinds of behavior to generate toward them.

The nervous mechanisms set up during embryological development is a structural cause not only for using input from the bodily condition to register telesensory input in a way that reveals the locations of perceivable objects in space, but also for the instinctive routines that use telesensory input to construct and use a map of its territory. The telesensory map is little more than a set of computational tricks that take advantage of the geometrical structure among salient objects on the surface of the earth to revisit energy sources and return to a nest or home base. Though computations on quantities like distance and azimuth and one-dimensional, stimulus-response chains for retracing pathways are effective, the isomorphism between states of the brain and the basic three dimensional structure of space is only implicit in them. Nor does it represent the effects of locomotion on the relations of objects in the territory, but merely guides actual locomotion.

These fixed action patterns built into the structure of the brain are called "programs of behavior" by J. Z. Young (1978, and 1981, p. 362), though Young assumes that they explain the behavior of mammals as well as that of other vertebrates and invertebrates.

The structure of space is, however, so important in determining the outcome of interacting with other objects in space that animals would be even more powerful, if the animal system of representation took greater advantage of it. Since material objects are substances that coincide with substantival space, they can change location, as we have seen, only by moving across space as time passes. And since space has a three dimensional structure, the effects of motion on the relations of objects in space is determined by the object’s speed and direction relative to them in space. This is a spatio-temporal aspect of the world, and adapting animal behavior to it would make animals more powerful.

Telesensory animals already adapt the spatial aspect of animal behavior to spatial aspects of the world. That is, they use their animal behavior over time to impose a kind of geometrical structure on the thermodynamic flow in a region that would otherwise require a giant machine. But instead of the unchanging geometrical structure of a huge material object, the structural cause is just an animal with a nervous system to guide its behavior so that it is in the right place at the right time to make things happen in the region that otherwise would not happen. Thus, it is an active, energy consuming way of imposing a geometrical structure that causes irreversible changes in the region that would not otherwise occur. This telesensory adaptation of the spatial aspect of animal behavior to spatial aspects of the situation is already to use a spatio-temporal aspect of behavior to control what happens to material objects located in the region.

Though animal behavior as such has a temporal aspect as well as a spatial aspect, telesensory animals do not adapt the spatio-temporal aspect of their behavior to the spatio-temporal aspect of the world. They adapt it only to the spatial aspect of the world. When they act on the perception of the object, it is the perception of the object in its current location. And if the other object is moving, that means guiding locomotion in relation to its current, albeit changing, position. However, when they act on their map of the territory, they assume that the locations of objects in their territory do not change. Their map gives them power over other objects by guiding locomotion in relation to unperceived objects whose locations do not change.

Animals would be more powerful, however, if they could adapt the spatio-temporal aspect of their behavior to the spatio-temporal aspects of the world.

If they could anticipate the consequences of the motion of objects on their relations to other objects in space, they could guide locomotion in relation not only to distant, unseen objects, but also in relation the future locations of objects that can move around in space. In chasing another animal, for example, they could move in the direction of its future location, rather than where it is currently perceived.

The capacity to anticipate the consequences of its own locomotion on the relations of their bodies to other objects in space would enable them, for example, to figure out an alternate route to its destination when the usual path is blocked, whereas the telesensory animal would be left with rigid routines that simply no longer work.

These examples emphasize the way in which anticipating the consequences of motion gives the animal foresight. But anticipating the consequences of motion is more generally useful, because, as we shall see, it is an understanding of the structure of space which makes the animal better able to take advantage of purely spatial aspects of the relations among objects in its territory than telesensory animals. In chasing another animal, for example, it could not only project its future location from its current motion, but also figure out where the animal might have gone in the territory when it can no longer be seen.

"Subjective" is an appropriate name for animals like this, because spatial imagination depends on internalizing the spatial structure of the world in a way that gives them an understanding of the structure of space. It depends, as we shall see, on a faculty of imagination in which sequences of memory images represent the consequences of locomotion relative to certain starting points. That makes it possible to think about spatial relations in terms of the consequences of locomotion (and motion generally), that is, as a spatio-temporal aspect of the world. That is to understand intuitively the role of space as an ontological cause of regularities about change, or “spatial causation.” (The use of sequences of image over time to represent what is possible means that this faculty might better be called “spatio-temporal imagination.” But it means that spatial imagination also includes the ability to record in memory and call up in imagination other spatio-temporal aspects of the world, such as regularities about change that do not have to do with motion, including how other animals behave).

Mammals have, therefore, a conception of space. They understand intuitively that space has three dimensions and what that means about the possible spatial relations among objects in space. They see other objects as being located in space. They even see their own bodies as having a location elsewhere in the same space as the other objects they perceive in space.

The subjective animal system of representation gives animals, therefore, the conception of the object as being located in space. But since location in space means having particular spatial relations to every other object in the world, spatial imagination is not merely a representation of the object as in space, but also a representation of the whole world, at least, in principle. And it is a world in which it can see its own body as just another object located in relation to every other object in the world.

This faculty of imagination enables animals to see the actual against the background of the possible, in this case, the actual locations of objects in space against the background of what is possible by motion. What space makes possible is presented as sequences of images along with perception (or the images derived from current sensory input), and thus, the possible has an appearance to the animal. The mammal’s animal representation of space is explicit.

None of this is even conceivable by the telesensory animal, because the location of the object is only implicit in its animal representation. When the telesensory animal focuses on the object, its location in space is not represented in the images caused by telesensory input. Its location is contained as a mere code for generating locomotion in relation to the object, should it choose to approach or avoid it, that is, as a disposition to move in certain ways. Thus, the telesensory animal is unaware that its own body is another object with a different location in space from the object being perceived. Indeed, it is not even aware that it has a body, except implicitly in special kinds of behavior, such as preening in birds, that has been selected for taking care of its own body. Otherwise its body is simply how it moves in relation to other objects and acts on them. It is as if the telesensory animal is its body, whereas the subjective animal is a subject to whom its body has an appearance, if only the appearance of being located in space relative to other objects.

Subjective animals require a higher level of part-whole complexity in the nervous system, because imagination depends on the capacity to generate behavior covertly and, by that covert behavior, to recall from memory the telesensory images that would result from those bodily movements. How the mammalian brain differs from the non-mammalian vertebrate brain is described below in detail, but first, the basic difference between the brain mechanisms of telesensory and subjective animals will be explained in functional terms.

Indeed, as an introduction to that functional description, the difference can be suggested by contrasting two kinds of computers.

Telesensory animals are comparable to the computer-guided robots found in factories and that have been used for exploring other planets. They can be programmed to generate routines in specific situations, but they rely on certain cues or landmarks to get around in space and, thus, can easily be confounded by changes in the locations of objects.

Subjective animals, by contrast, are comparable to computers that generate for beings like us what is called "virtual reality". In the computer memory are stored images of what would be seen if the human head were pointed in certain directions at each location for a whole set of locations to which a body can move, so that when sensors attached to a human body detect such bodily motion, they call up the appropriate image from the computer memory and project it onto a screen in front of the eyes, giving a human subject the appearance of moving around among the objects in some region of space. It generates an uncanny sense of being in an imaginary world, because the human being is playing the role of generator of "covert behavior" exploring a memory that is supplied by the computer, just as real covert behavior explores the memory of the subjective animal system of representation.

Functional diagram of subjective animal behavior guidance system. The various functions and subfunctions of the subjective animal system of representation are depicted in the accompanying diagram of the subjective animal behavior guidance system. Though neural mechanisms serving the function of selecting the kind of behavior are also essential to the animal behavior guidance system, only the mechanisms serving the sensory input and behavioral output subfunctions are involved in the animal system of representation (all the parts with the gray background). The higher level of neurological organization is suggested by the contrast with the diagrams of the somatosensory and telesensory animal behavior guidance systems (which are also provided for comparison.)

In the subjective system, the sensory input and behavioral output systems both depend on an interaction of at least three brain mechanisms, each at the same level of neurological organization as the whole sensory input or behavioral output system of telesensory animals. Indeed, as the diagram suggests, each is a complete circuit of such mechanisms.

The brown squares and lines are basically the systems and causal connections serving the functions that are also served by the telesensory animal system of representation (including telesensory input, input about the current bodily condition, their combination as the perception of the object, and how that is responsible for overt behavior when some kind of behavior is selected). The higher level of part-whole complexity in the subjective sensory input and behavioral output systems makes it possible for them interact in the more complex way that constitutes imagination.

The red circles and lines (in each brown square) represent the systems and causal connections serving new functions required by spatial imagination (including the body image, covert locomotion, memory, the local image, the sequences of images, or spatio-temporal images, called up from memory by convert locomotion, and the behavior generator). Here is how it works as a faculty of spatial imagination.

(The three systems in each complete circuit include a thalamic nucleus, at least one region of neocortex, and a third structure of some kind, which is suggested by the two circles and a little ball. The neural mechanisms serving these functionally described systems are identified in the next section, on the structure of the mammalian brain.)

Local image.The telesensory input registered by the sensory input system includes all the telesensory modalities. Vision and hearing are most central, though olfaction is still used. Input about the current bodily condition has the same function with respect to telesensory input as it does in telesensory animals, except that by handling all the telesensory modalities together, it can construct a more complete representation of the current scene, or what is labeled as the “local image.”

Though the local image represents only objects that can be perceived from the animal’s current location, it also represents some objects that are not currently causing telesensory input. Telesensory input from objects located behind the animal at the moment, for example, is registered in short-term memory according to the bodily condition at the time it was perceived, while the objects on which the eyes focus or that are making noise are currently causing telesensory input. But since these telesensory images are all part of the local image, objects are perceived as being located relative to one another in the current scene, and behavioral output can be adjusted to them all (when some kind of behavior is selected).

Though the local image is a complex of many telesensory images which can guide behavior in relation to many different objects, it is the unit that becomes connected in sequences as the subjective animal’s territorial map in spatial imagination.

Body image.Overt behavior is caused by motor output to muscles throughout the body. The behavioral output system is labeled the “body image” because commands for overt behavior are sent from a representation of the body. The body image is a spatial structure in various 2-D arrays of neurons that represents somatotopically all the parts of the body whose behavior it controls, and it receives somatosensory input from all the same parts of the body, indicating the positions and motion of limbs, the stress of muscles, tactile sensations from the skin, and pain from injuries.

Tactile sensations reveal information about objects that contact the body, and since the stance of the body is represented, it reveals information about the location of the other object causing the somatosensory input. (Such information is registered as part of the local image by way of its input about the current bodily condition, though there are reflexes that can trigger behavior locally without involving the selection system, for example, in response to intense heat or pain.)

Behavior generator.Most motor commands in the body image are generated, however, by another part of the behavioral output system, labeled the “behavior generator.” The behavior generator contains schemata for all the various kinds of behavior that may be selected, and depending on its input from the goal selection system, the behavior generator uses one of them together with the perception of the object as located in space (that is, the local image, its input from the sensory input system) to generate precise motor commands that are adapted to the locations of relevant objects in the current scene. Thus, behavior may be guided in relation to perceivable objects even though they are not currently causing any telesensory input.

Moreover, the behavioral schemata used by the behavior generator may involve many steps, because the behavior generator has feedback from the motor commands issued by the body image by which each motor command triggers the next in a sequence, generating temporally complex patterns of behavior. There is a wide range of variations on behavior that may be included in such behavioral schemata, since motor output sends commands separately to each part of the body.

Thus far, the subjective animal system of representation serves basically the same functions as the telesensory animal with respect to currently perceivable objects, though in a more complete way, since its higher level of neurological organization integrates all the kinds of telesensory (and somatosensory) input as a local image on the input side and can generate a great variety of long sequences of complex motor commands on the output side. What is new is spatial imagination. Though spatial imagination serves the same function as the telesensory map of the territory animal, it is so much more complete that it represents an aspect of the world that inevitably escapes telesensory animals: regularities about how motion and locomotion affect the relations of objects in space. That is the source of the subjective animal’s conception of space.

Memory. The new subsystem in the subjective animal’s sensory input system is a special kind of “memory” which is able to record images in sequences so that they can be called up in the same sequence. The images may be just telesensory images of an object, for example, recording what happens as another animal behaves. But they can be entire local images. That is, various telesensory images representing a local scene (with each registered according to the bodily condition relevant to receiving it) can be recorded together as a memory unit, and local images can then be recorded in sequence according to the direction of its locomotion. The effects of locomotion in different directions from any given scene are recorded in different sequences.

Overt locomotor behavior is registered, not only in the local image by way of input about the current bodily condition, but also directly in the memory system by way of the “covert locomotion” connection. The direct connection to memory is what is used to label local images in constructing the map.

Covert locomotion.What calls up the local images recorded in this way is a new capacity of the subjective behavioral output system, the capacity to generate behavior covertly as well as overtly. In covert locomotion, the same motor commands that would otherwise cause locomotion in a certain direction relative to a local image are generated, but in a way that does not affect the body. It affects only the memory based in the sensory input system. Since local images have been recorded as units labeled by the appropriate bodily condition (mainly the stance of the body, head, eyes, ears and the like), and since local images have been connected in sequences according to the bodily condition at the time (mainly the direction of locomotion relative to the local scene), covert locomotion calls up the sequence of local images that would be encountered if the animal actually moved in that direction. The local images called up from memory are projected in a sequence over time to the behavior generator in the same way as images of perception, though they are just memory images (labeled “spatio-temporal images” in the diagram) and can occur faster. Thus, the behavior generator can use the local images from memory to generate covert locomotion in relation to unperceived objects in the same way as perceived objects, drawing on its schemata for various kinds of locomotion and generating motor commands in relation to objects in the imagined local scene (represented by the local image).

Together, such sequences of local images serve as a map of the animal’s territory. For example, if a local image that turns up in exploring one sequence by covert locomotion is registered as (or simply recognized as) part of another sequence of local images representing locomotion in another direction, the subjective animal can change the direction of its covert locomotion relative to that local image and anticipate what would happen from turning at that location in the other direction. In familiar territory, such sequences of local images are richly interconnected, but in any case, they give the subjective animal a map of the relations of objects in its territory. The subjective map is different from the telesensory map, because it can guide covert as well as overt locomotion in relation to goals picked out by the selection system. Thus, far from being merely a conditioned stimulus-response chain that leads the telesensory animal from one location to another as parts of a instinctive routine for controlling a specific relevant condition, memory is a potentially complete, general purpose map of all the objects in its territory which can be explored in imagination by covert behavior.

Evolution of behavioral schemata within the brain. Locomotion, covert or overt, is generated by behavioral schemata, and not only do subjective animals have many different ways of moving and turning in relation to other objects in space, but they also have other kinds of behavior. Though schemata for basic forms of behavior may be built into the structure of the brain (indeed, must be in the case of mammals that have to be capable of locomotion from birth), they can also be learned. And in any case, the consequences of acting on them is learned, and thus, how to adapt them to the situation is learned. Learning transforms the subjective animal’s map of its territory into an understanding of the structure of space, and we can see why, by recognizing that learning is a from of evolution by reproductive causation. Subjective animals learn as behavioral schemata evolve in the brain as the result of a form of natural selection that I will call “reinforcement selection.” Learning is a later phase of neurological development that occurs when the animal is interacting with the world, and its effect is to internalize certain aspects of the world in the skills and imagination of the subjective animal. Let me describe how learning can be seen as a contained form of evolution by reproductive causation, setting aside until later discussion of the neural mechanisms that serve these functions.

The “reproducing organisms” in this case are the behavioral schemata used by the behavior generator to generate motor commands in the body image. They go through reproductive cycles in the sense that, once they have generated behavior, they can do so again.

Variations on behavioral schemata are possible, because behavior is generated by motor commands to all parts of the body from the body image. Not only can highly varied (and finely tuned) kinds of behavior be generated, but such complex motor commands can also be generated in different sequences over time as parts of a single action. By rearranging the motor commands, variations on behavioral schemata can be generated more or less randomly.

The natural selection of behavioral schemata is made by their being recorded in memory. Such recordings increase the likelihood that the same kind of behavior will be generated again. (Basically, the synapses among the neurons used to generate the behavior are strengthened.) The behavioral schema reproduces when it is used again to generate behavior.

Since behavioral schemata are used to generate behavior in conjunction with the perception of the object acted on, they are recorded together with telesensory images of those objects in the local image. Two kinds of connections are established between telesensory images and behavioral schemata. Telesensory images of objects (or their local images) that precede the behavior may help trigger the behavioral schemata, when they recur in perception. And when behavioral schemata are used to generate covert behavior, they call up telesensory images (or local images) of what results. These connections are the way local images are recorded in sequences, so that they can be called up as spatial imagination, by locomotion and turning.

The criterion for natural selection (that is, recording it in memory) is basically whether the behavior generated by the schemata satisfies a relevant desire. The recording is made by the memory circuit, and its criterion comes from its relationship to the goal selection system. Random variations that do not succeed in satisfying desire are not recorded.

In learning basic kinds of behavior, the relevant desire is mainly just that its expectations about telesensory images be confirmed by what shows up in perception. The ecological niches are basic behaviors required to perceive objects in different directions and to move from one local scene to another, and the behavioral schemata that are adapted to those ecological niches internalize some basic aspect of the world.

This contained form of reproductive causation is the mechanism, in mammals, that behaviorists, like B. F. Skinner, called “operant conditioning.” What they called “operant behavior” is behavior generated by behavioral schemata. What they called “reinforcement” is natural selection by recording the behavioral schemata in memory. What they called “discriminative stimuli” are the telesensory images (or entire local images) that help trigger the behavior again.

Explaining operant conditioning in terms of the subsystems of the subjective animal behavior guidance system enables us to see this important kind of learning as a form of gradual evolution. Behavioral schemata start off simple, uniform and weak, and as a result of “reinforcement selection,” they become complex, diverse and powerful in generating behavior that can satisfy desire. The gradual evolution of behavioral schemata is the increasing power of the animal to control relevant conditions.

Though it is contained within the individual brain, it is a form of reproductive causation. Not only is natural selection made by success in reproduction, but reproduction is also what forces a selection to be made. The ecological niches in which behavior schemata can complete their reproductive cycles are situations in which the animal must behave in some way, and the reproduction of one behavioral schema (by its reinforcement) in such an ecological niche tends to cause a “scarcity” of opportunities for other behavioral schemata to be generated, because the animal can behave in only one way at a time as situations of that kind arise. To be reinforced, a behavior schema must generate its behavior at some time before its memory group fades away from disuse, and thus, the scarcity is caused by how reproductive cycles add up in time (rather than by how reproductive cycles add up in space as time passes, as in biological evolution). But as random variations on behavioral schemata are tried out in such an ecological niche, those that satisfy the desire most efficiently are reinforced, and thus, “reinforcement selection” causes a stage of gradual evolution in which each behavioral schema becomes maximally efficient at satisfying some desire in certain situations (its ecological niche), and the combination of behavioral schemata at the ecological level, or the animal’s repertoire of behavior, comes to satisfy all its desires in all the situations it encounters as fully as possible with the least effort required. At both the individual and ecological levels, therefore, behavioral schemata change in the direction of natural perfection, that is, doing the most with the least.

What the doctrine of operant conditioning leaves out, however, is the faculty imagination. Though operant conditioning may be adequate to explain learning in telesensory animals, it leaves out important aspects of learning in subjective animals that depend on spatial imagination.

The relevant consequences of behavior are not limited to whether the behavior is reinforced or not. When a behavioral schema is reinforced, what happens, that is, the telesensory images (or local images) of what happens, are also recorded in conjunction with the behavioral schemata. Thus, when a behavioral schema is generated covertly, those images are called up in memory. Thus, when the subjective animal moves or turns covertly in the local scene, it can anticipate the objects and other local scenes it will encounter. This is a map of the animal’s territory, because when covert locomotion or turning is made relative to a local image, it calls up other local images relative to it. Thus, the subjective animal can explore its territory in imagination.

But the capacity to record and recall local images according to locomotion is not just a map of a particular territory. Learning to construct and use memory maps gives the subjective animal a general conception of space by which it can understand any relations in space by imagining the kinds of motion that would be involved in traversing or changing them. This general understanding comes from how the memory system reinforces behavioral schemata. The same kinds of locomotion have the same kinds of effects in similar local scenes. For example, when confronted with a large object, moving around it to the right and then turning left will give one a different view of the object. Or when one encounters a hill, climbing it will give one a view of what is on the other side. Two right turns in succession sends one in the opposite direction. Thus, by recording local images with similar structures together as the same generalized local image, covert locomotion becomes a general understanding of the structure of space, because the subjective animal has a “map” of the consequences of locomotion that would work for all local scenes of that kind. And by generating a sequence of locomotor schemata in sequence, it could anticipate the general consequences of combining them in certain ways.

In other words, the spatial structure of the world is internalized in spatial imagination because of how the memory system records behavioral schemata. It is the spatial structure of the world that accounts for the regular connection between kinds of locomotion or turning and the kinds of changes that occur in local images, and a behavioral schemata evolves by reinforcement selection, the connections in the memory system internalize those general relations. Their internalization is the subjective animal’s conception of space.

Understanding the structure of space.Though spatial imagination is based on a map of the territory in which the consequences of locomotion are represented by sequences of local images, the way that behavioral schemata evolve within the brain by reinforcement selection means that it is also a more general understanding of the structure of space. That is, it internalizes not only the particular relations among material objects in the animal’s territory, but it also internalizes the structure of space itself. In both cases, it is spatial imagination, because the understanding comes from the sequences of local images that can be called up covert locomotion (and turning).

What would happen because of locomotion (or the motion of any object) relative to objects in a local scene can be anticipated, because spatial imagination, that is, the capacity to generate behavior covertly, calls up from memory sequences of local images that represent the consequences of such behavior. The local images can be particular or general. Covert behavior acts on memory in similar ways in both cases. The difference is whether covert behavior engages with the detailed, particular local images that are the map of its territory or it operates on more generalized local images, which contain only certain relevant features. (They are actually groups of more specific memory images. We shall see how such general memories are possible when we take up the nervous mechanisms that serve these functions.)

Since spatial imagination gives the subjective animal an understanding of the effects of locomotion and turning in any space, it can see the objects in any local scene as being located in space. That is, the way that general local images are called up in sequences up by covert locomotion represents general regularities that are caused ontologically by the structure of space, and since those regularities hold not only among local scenes, but also among the objects within any local scene, the subjective animal has an intuitive understanding of the constraint that space imposes on change. That is the sense in which it perceives the object as being located in space. It is a conception of the structure of space.

Since spatial imagination gives the subjective animal a conception of space, the subjective animal sees not only other objects, but also its own body, as located in space. The local image is organized relative to the body, since telesensory images are combined as parts of it according to input about the current condition of the body. But since the subjective animal eventually acquires an understanding of the structure of space, that understanding applies to objects within the local image, and that includes the ability to think about the body as another object in space. The subjective animal can imagine not only its own body moving relative to other objects in the local scene, but also the effects of other objects moving in relation to its own body — as well as relative other objects in the local scene. Thus, even the body itself is represented as an object in the local image.

To sum up, we might even say that the subjective animal is able to see the world as a whole. To be sure, its map of the relations of objects in space is limited to objects in its territory. But it has a way of understanding spatial relations that can be extended, in principle, to include every object in the world. Thus, given how the world has a wholeness that comes from the structure of space, the mammal sees the world as a whole. Since such subjective animals have an intuitive (nonlinguistic) understanding of how a world of objects in space is inherently whole, they can perceive objects as part of a single whole.

Behavioral evidence of spatial imagination. As suggested at the outset, spatial imagination makes subjective animals more powerful than telesensory animals in various ways.

Spatial imagination give the subjective animal a map that not only guides instinctive behavior in relation to objects in its territory, but also enables the animal to see particular objects as having particular locations relative to others. It is a set of beliefs about the whole world that is based on being able to understand the consequences of motion relative to them. And since it is a general purpose map of the animal’s territory, rather than just an elaboration of instinctive routines for acquiring energy, mating, avoiding predators or the like, it can be used in pursuit of goals that were not relevant to its being acquired.

It enables subjective animals to plan new routes to goals when their paths are blocked, to figure out how to escape predators, to predict which direction prey might run, to choose the best way to catch them, and the like. It is the "inner world" to which Dennett (1975) was pointing in his famous essay, "Why the Law of Effect Will Not Go Away", when he said (paraphrasing Popper) that animals have an inner world that allows "hypotheses to die in their stead".

It gives subjective animals a primitive way of reasoning, for they can draw inferences about a world of objects in space. The animal system of representation is based on the assumption that objects do not come into existence or go out of existence, and with spatial imagination, that assumption can, for example, be used to infer where an object that it is seeking is located by knowing where it is not located and has not been. As a form of understanding, therefore, spatial imagination is a way of using current beliefs to form new beliefs, that is, a way of making inferences.

There is empirical evidence that spatial imagination makes mammals more powerful than non-mammalian vertebrates.

But it should be noted that not everyone agrees that mammals are more intelligent than non-mammals. In a study by Macphail (1982), the behavioral criteria used to argue that mammals are not measurably more intelligent than non-mammalian vertebrates do not take into account the capacity to get around in space. And although Gallistel (1990) recognizes that memory files are labeled spatially, he does not recognize the difference between the instinctive computational routines used by telesensory animals and a subjective memory based on the three dimensional structure of space. In general, there is no recognition in the literature of mammalian superiority.

Experiments demonstrating that rats use a representation of the spatial relations of objects in the local scene to orient their locomotion are reviewed by Gallistel (1990, Ch. 6). And rats that were not merely conditioned to the unusual environments that Gallistel discusses, but raised in them, should make even better use of the cues about spatial relations of objects in the region, because they would have internalized a map using input about the kinds of bodily conditions required. In any case, it is easy for mammals to learn mazes, because the mechanisms of spatial imagination acquired from experience with a world of objects in space would enable them to construct a new map for the maze.

There is evidence of inferences based on spatial imagination in how mammals in familiar mazes take advantage of apparent new shortcuts to the goal in otherwise familiar mazes. For example, if, at some point in a maze that a rat has learned, the normal route is blocked and barriers are removed both in the direction of the goal and in the opposite direction, the rat will take the new route to the goal, not the other one. (See Charles Taylor, 1964, pp. 161.196. These experiments pose a problem for traditional learning theory, which explains maze behavior as chains of discriminative responses. See also Gallistel 1990, Ch. 5.)

Even birds do not take advantage of shortcuts (when walking) through mazes, despite being able to learn mazes almost as quickly as mammals. In fact, once birds have learned a maze, it is surprisingly difficult for them to learn changes in it at all. Although birds have a mammal-like memory circuit, this suggests that, at least, when it comes to walking, it is not a spatial imagination that gives them an understanding of the structure of three dimensional space.

Subjective animal behavior guidance system.The faculty of spatial imagination serves as the animal system of representation in subjective animals, and in order to be of use in guiding behavior, the right kind of behavior for each situation must also be selected. Indeed, selecting between incompatible kinds of behavior is the original function of the animal behavior guidance system. And imagination also makes subjective animals better able to tell which goal to pursue in the situation.

The goal selection system.The kind of behavior generated must be made to depend on the situation, either the kinds of objects that are present in the local scene or the current needs of the body (or both). In subjective animals, goal selection is not just a matter of instinctive routines, but depends on desires, which are dispositions to behave in certain ways. Thus, its goal selection system might also be called the “affective system.”

The seat of desire is the goal selection system, for it registers of the various needs of the body and keeps track of the success of behavior in satisfying each of its desires.

Special input from the body is supplied to the goal selection system by the biological behavior guidance system (not represented in the functional diagram).That keeps the goal selection system informed of the body's need for food, water, sleep, mating and the like.

Objects represented in the sensory input system also have affective labels, which can arouse desires in the goal selection system or determine which object to pursue when a desire is already aroused. Some affective labels are instinctive, that is, built into the structure of the animal behavior guidance system, such those for avoiding certain predators and mating. Other affective labels are attached to objects by the goal selection system according to past experience. That is, the goal selection system can use the results of behavior to label objects by their capacity to satisfy desire, so that objects can be recognized for their capacity to satisfy desire when they are encountered again.

In either case, when the object turns up in the sensory input system, the desire may be triggered. But if the desire is aroused by bodily needs, telesensory images of the relevant objects may be called up from memory by their labels.

Whether the desire is aroused by sensory input or bodily needs, the goal direction system selects the appropriate kind of behavior by strengthening a certain behavioral schema in the behavior generator. (This is represented in the functional diagram by the projection from the goal selection system to the behavioral output system.) In other words, in terms of behavior, desires are dispositions to behave in some way, such as eating, mating, fighting, fleeing, and sleeping. But since animal behavior acts on objects in space, the desires that have this effect on the behavior generator must also be attached to an object.

When the object represented by sensory input is what arouses the desire, the object for the behavior schema to act on is already determined. If there is an obstacle in its way, it poses a problem that the subjective animal may be able to solve by spatial imagination. For example, it may use covert locomotion in its map of the territory to figure out a route that would put its body in the right location to act on the object as it is disposed to.

If the desire is aroused by bodily needs, the behavioral schemata it calls up may include searching for objects that will satisfy it, as in foraging for food and finding shelter. Or it may call up images of objects that will satisfy it, and if such images happen to be part of some local image in the map of its territory, the mammal can explore its map covertly to set up the locomotion that will lead to it.

In either case, instead of the telesensory animal’s rigid instinctive routines, desires set practical problems to be solved by using spatial imagination to imagine alternatives, and so subjective animals would be able to behave in a more flexible and adaptive way when necessary.

The goal selection system is the third essential subsystem of the animal behavior guidance system (along with the sensory input and behavioral output systems), and though it is not depicted in the functional diagram, it is also on the subjective level of neurological organization, like the other systems. There is a seat of desire, and it interacts through a complete circuit of connections with the other two subsystems. That is how it is able to attach the desires, or dispositions, to the right objects.

Sleep and dreaming.Dreaming, or REM (rapid eye movement) sleep, evolves with mammals (although there is some evidence of it in birds), but it has long been puzzling what its function could be. Given the evolution of spatial imagination in subjective animals, however, its function could be to try out random variations on behavioral schemata so that reinforcement selection can be more selective in attaching the right desires to the right objects in the right situations.

The attachment of desires to objects is a crucial function in behavior guidance, because it sets the goals for animal behavior. The animal will not be as powerful as possible, for example, if it fails to attach the desire to eat to objects from which it can acquire food, and it can be disastrous to attach the desire to eat to a predator. Furthermore, the task becomes increasingly complicated as the behavioral schemata for satisfying certain goals become increasingly complex. In the behavior schemata for attaining certain goals, behavior towards several objects of various kinds may be involved. Special routes through the territory may be needed to acquire food in certain ways. Some locations or objects may be dangerous. And social relations require different attitudes toward different members of the group not only in the family but also when there is a dominance hierarchy.

Reinforcement from satisfying desire is responsible both for attaching desires to objects and for strengthening behavioral schemata for satisfying them. Indeed, they are the same thing, because behavioral schemata that are naturally selected by success in satisfying certain desires include images of the objects and situations in relation to which the behavior generator sets up the motor commands. But natural selection by reinforcement is not very selective when success comes from subtle variations on complex behavioral schemata or accidents. Established behavioral schemata may be more powerful with their parts rearranged. Thus, reinforcement selection would be more effective in making behavior maximally powerful, if it had a wider range of random variations from which to choose, as long as it did not risking making disastrous mistakes.

Spatial imagination makes it possible for subjective animals to try out random variations on behavioral schemata in a safe way. Indeed, the regular use of spatial imagination in that way may be the function of dreaming.

Behavioral schemata are connected with both the desires and situations in which they are acted on, but they are often complex behavioral schemata, and thus, if the subjective animal could shuffle the elemental schemata making up its habitual repertoire and try out new combinations, testing them by the consequences associated with each in past experience, it could discover new complex behavioral schemata that are likely to work better.

If the trials were informed by memory of past successes and dangers, the random variation would come with certain emotions attached, including warning of possible dangers in acting on them as well as the attraction of potential benefits.

Dreaming requires long periods when the animal was not otherwise occupied, and that would be provided by regular periods of sleep. Indeed, if dreaming is functional in this way, it may be the function that explains sleep in mammals.

For further evidence of this function of dreaming, see Jonathan Winson's Brain and Psyche: The Biology of the Unconscious.

Acting. The selection of the kind of behavior toward an object is, however, a multi-step process. First, the goal selection system attaches a desire to the object. The animal system of representation must then figure out how to adapt a relevant behavior schema to the world. Finally, something must trigger the command to convert covert motor commands into overt motor commands. That is, it must act on its plan. The systems responsible for the first two steps have been explained, but the decision to act on its plan requires an additional mechanism. When we take up the structure of the mammalian brain, therefore, we will also be looking for a mechanism that makes acting overtly depend on a state of the animal behavior guidance system as a whole.

The possibility of a subjective level of neurological organization.The functional representation of the subjective animal system of representation makes it clear that any animals that happened to try out such a behavior guidance system would be able to acquire an entire range of new powers for controlling relevant conditions in a long period of gradual evolution. They would, in other words, begin a new stage of animal evolution, refining the inherent powers of spatial imagination and adapting it to all available ecological niches. But in order to conclude that such an evolutionary stage is inevitable, it must be possible for a radical random variation to try it out. There are good reasons to believe that it is possible, but in the end, the most compelling case depends on seeing how these functions are served by nervous mechanisms.

It may seem that any neural mechanism complex enough to realize this functional description of the subjective animal system of representation would be too complex to be tried out as a radical random variation on the telesensory system by the multicellular biological behavior guidance system. The functional diagram indicates that it requires a higher level of neurological organization than telesensory animals. But since the mechanism of embryological development must get all its instructions from the structure of the nucleus and the chromosomes it contains, such a higher level may seem beyond the range of random variations being tried out, especially considering that more complex neural connections are needed for higher level systems to interact as an animal behavior guidance system.

This is the same kind of problem that we faced in explaining the eukaryotic and multicellular levels of biological organization. But there it required a new kind of biological behavior guidance system, and here a different kind of solution is required, for the same biological behavior guidance system is responsible for all the levels of neurological organization. The appropriate random variation must somehow occur in the multicellular biological behavior guidance system (the process of embryological development).

There are at least three reasons for believing that such a random variation is possible.

First, one reason was found in how deuterostome embryological development is different from proterostome development. With the neural tube divided into segments, the mechanism of embryological development can address entire 2-D arrays of neurons and determine them, as a whole, to migrate or send processes to other areas of the neural tube (or the body), and to make topologically ordered connections with 2-D arrays of neurons there. That means, as suggested earlier, that the units from which deuterostome development constructs the nervous system are already on a higher level of organization than in proterostome development — not to mention that the connections among such units can be made without interference with the development of other organs in the body, since the neural tube itself is separate from the rest of the body.

Second, it is not necessary for the mechanism of embryological development to prescribe all the neural connections involved in the subjective animal system of representation, because the three basic systems are laid out in such a way that most of the detailed connections they require can be acquired from the world by learning. Since the power of animal behavior comes from adapting it to spatial and spatio-temporal aspects of the world, it is possible to internalize the detailed structural causes of the brain mechanisms that serve that function from experience with the world. The world already has a spatial structure, and if the animal is protected and cared for during the first part of its life, its interactions with the world can internalize the structures needed to construct local images and maps of local images that can be explored by covert locomotion. Thus, much detailed structure can be supplied by the contained form of reproductive causation mentioned above, in which behavioral schemata evolve by reinforcement selection. This is the role of nurture as well as nature in neurological development.

Third, given how detailed neural connections can be internalized from the structure of the world by experience, that is, learning, all that is necessary is a random variation that would set up the basic structure on a higher level of neurological organization within which those detailed structures can be acquired. As it happens, there are two, connected kinds of changes in the embryological development of the non-mammalian vertebrate that do set up a higher level of neurological organization in the mammalian forebrain.

In order to give this final argument for the possibility of the subjective level of neurological organization, therefore, we must consider the structure of the mammalian brain.

Starting with the functional diagram of the subjective animal behavior guidance system, I will, first, simply identify the neural mechanisms in the mammalian brain that are responsible for each of the subsystems. This is to view the structure of the mammalian brain from a rather high altitude. It affords a general impression of how the mammalian brain works, and for those who are familiar with its structure, it will be possible to see how it explains the functioning of the mammalian brain.

Second, I will explain how this functional explanation of the structure of the mammalian brain would also explain the contained form of reproductive causation by which behavioral schemata evolve in the individual brain by reinforcement selection.

Finally, in order to show how the subjective level of neurological organization is possible, I will show how it could arise from two basic, yet simple changes in the non-mammalian vertebrate brain. That will involve a much more detailed description of how the functionally identified systems are realized in the mammalian brain.

Neural structure of the subsystems of the subjective animal behavior guidance system. In the diagram of the subjective animal behavior guidance system, the systems that were previously defined functionally are labeled by parts of the nervous mechanism that serve their functions in the mammalian brain. (The functional diagram is included for comparison.) The brain mechanisms involving the neocortex are depicted as beveled buttons, while the thalamic nuclei projecting to them are depicted as purple spheres. Notice that when we look more closely at the detailed structure, the behavior generator itself is a complete circuit of telesensory-level nervous mechanisms. That is because there are two, distinct circuits within the behavioral output system, one that supplies the behavioral schemata and generates covert behavior and the other that also generates overt behavior. (Covert behavior needs only the ventral anterior thalamic nucleus, whereas both it and the ventral lateral thalamic nucleus are involved in generating overt behavior.) The part of the frontal neocortex that contains the behavior schemata and where covert behavior is generate is labeled “Sch.”)

This key to the neurological interpretation of the functional diagram of the subjective animal behavior guidance system may be enough for those who are familiar with the structure of the mammalian brain to see the functional diagram as an explanation of how the mammalian brain works. But for those who are not familiar with the structure of the mammalian brain and want a briefer, more intuitive way of seeing how it realizes these functionally defined systems, the following diagrams and brief explanations may suffice.

In the mammal, the entire animal behavior guidance system is located in the forebrain, and its basic structure is composed of two main units, the thalamus and the neocortex. The thalamus is at the end of a brain stem, just rostral to the midbrain, hindbrain and spinal chord, and it sends a massive projection to all parts the neocortex, which encloses the rest of the forebrain. (A projection is a set the axons from a 2-D array of neurons in one region to a 2-D array of neurons in another region, taking full advantage of the chordate’s way of constructing the nervous system in the neural tube.) The nuclei in the thalamus send their projections mostly to different parts of the brain (though the anterior temporal cortex receives none). There are also projections back from the neocortex to thalamic nuclei by which they interact in some way, but the main direction of influence is from the thalamus to the neocortex. These thalamic projections are 2-D arrays of neurons in which the information conveyed by the firing of any single neuron depends on the neuron's position in the 2-D array as a whole, and the thalamus apparently has the function of synchronizing the processing in all the parts of the neocortex.

There are three grand, distinct circuits of connections, each involving many such 2-D arrays, that pass though the thalamus and the neocortex back. That is, each circuit uses some part of the projection of many 2-D arrays from the thalamus to the neocortex, but each has a special way by which the neocortex completes the circuit of multiple 2-D projections by acting on those same thalamic nuclei (that is, distinct from the connections by which the neocortex reacts to the thalamus directly). Each such circuit is one of the three main subsystems of the animal behavior guidance system, with the circuits themselves on the subjective level of neurological organization. (See diagram of the basic structure of the mammalian brain.)

In the framework of this basic diagram, we can see how each of the functionally defined subsystems is realized by the mammalian brain. Consider first the sensory input system. Visual input from the eyes is relayed by the lateral geniculate nucleus (labeled "LGN") to the occipital (or striate) cortex where there are numerous copies of the entire image from the retina of the eye. Auditory input is not represented in the diagram, though it is handled in the same way, with auditory images in the superior temporal lobe. The inferior parietal neocortex is where the telesensory images are assembled as the local image (using association fibers from the motor areas, or body image, to supply information about the current bodily condition, also not depicted). The activity of the inferior parietal area in constructing the local image also depends on its interactions with a thalamic nucleus called the "pulvinar" or (labeled "Pul.," which receives input from the superior colliculus in the midbrain, the main visual image in the non-mammalian vertebrate brain).

The memory is what gives the sensory input system a complete circuit from the thalamus through the neocortex back to the thalamus for another projection to the neocortex. The memory circuit receives information about the telesensory images and how they have been combined as the local image in the anterior temporal neocortex where the hippocampus is located. In fact, almost every region of neocortex sends association fibers (or chains of association fibers) toward the anterior temporal neocortex, where they are assembled for the hippocampus (in an adjacent region, called the “entorhinal cortex”). The hippocampus projects by way of the fornix to the anterior nucleus of the thalamus, though many of its fibers pass first to the mammillary body (located in the hypothalamus) which relays them to the anterior nucleus. The anterior nucleus projects to the entire cingulate gyrus, which is the extreme medial edge of neocortex adjacent to both anterior and posterior regions of neocortex. The cingulate neocortex has two way connections with neurons in adjacent areas of neocortex. That completes the memory circuit for the local image and its bundle of telesensory images, since those images are affected by their own projection through the memory circuit. And the function of this circuit is to form memory groups of neurons throughout the neocortex that are involved at some moment in the (synchronized) processing the image of some local scene. That is, by strengthening the synapses among the neurons involved throughout the neocortex, the whole group tends to fire when some crucial group of them fires for some reason, recalling the local image.

The behavior generator for covert behavior receives the local image (and its telesensory images) by way of the projection from the entire posterior neocortex to the caudate nucleus of the corpus striatum. That is the perception of the object in space that is used to guide behavior. The corpus striatum also receives a projection from the entire anterior neocortex, which includes both its perception of its own body and the behavioral schemata contained in the frontal neocortex. The corpus striatum can project to both the ventral lateral and ventral anterior nuclei of the thalamus, but when behavior is covert, the projection to the ventral lateral nucleus is suppressed and only the ventral anterior nucleus is affected. The ventral anterior nucleus projects to the entire frontal neocortex (except for the motor neocortex itself and supplementary neocortex). Thus, when behavior is covert, the premotor neocortex and behavioral schemata located in the frontal area are both also projected to the anterior cingulate gyrus, and since the anterior cingulate neocortex projects to the posterior neocortex and, indirectly, to the local image, covert locomotion can call up images from memory in sequences, as required for spatial imagination.

The body image for overt behavior includes the motor neocortex, supplementary motor neocortex and somatosensory neocortex, all of which are organized somatotopically, like an image of the body. The overt bodily image is the source of motor commands to all parts of the body, but it is mediated by a projection (not depicted) from the overt body image to the cerebellum and its projection back to the motor neocortex by way of a part of the ventral lateral nucleus of the thalamus. (The cerebellum evens out the gross motor commands of the premotor and supplementary motor areas both spatially and temporally so that the precise motor commands work together smoothly in generating the prescribed behavior in the body as a whole.) This overt body image located in the neocortex is also the source of the input about bodily condition that is used to construct the local image. Its projection (via association fibers) to the inferior parietal neocortex is used to combine telesensory images as the local image representing the spatial relations among object in the current local scene relative to the body. Finally, the overt body image also sends a projection to the anterior cingulate neocortex, and since it projects to the posterior cingulate, the overt body image provides the labels for recording memory images according to the locomotion and turning that are responsible for them.

When behavior is being generated overtly, both parts of the circuits through the corpus striatum are active. A behavioral schema in the frontal neocortex is used to set up behavior in the premotor area, and when the signal (from the centromedian nucleus of the thalamus) to the putamen calls for the behavior to be generated overtly, the schema is used to send motor commands to the body. (The centromedian nucleus is in a position to tell when to generate behavior overtly, because it is at the center of the thalamic nucleus receiving processes from all its nuclei as the thalamus synchronizes processing in all parts of the neocortex.) When behavior is overt, the anterior cingulate gyrus receives input from both the overt and covert body images, and thus, the labels attached to memory groups that are formed when behavior is overt can be used to recall those images in sequence as spatial imagination when behavior is covert.

All the circuits combined are the subjective animal system of representation. The auditory system (in the superior temporal neocortex) and the tactile system (in the superior parietal neocortex) are not depicted.

All that is needed to complete the subjective animal behavior guidance system is the goal selection system. It is also a complete circuit through both the thalamus and the neocortex. The route from the neocortex back to the thalamus so that a circuit can be completed is provided in this case by the amygdala. Located in the anterior temporal lobe, the amygdala receives the same information from throughout the neocortex that the memory circuit receives by way of the hippocampus, except that it passes through an ancient form of cortex surrounding it (the piriform cortex). Thus, the amygdala is in a position to attach desires to the objects (or read affective labels already attached to objects) that are used by behavior schemata to generate behavior in relation to them. The amygdala projects to the dorsomedian nucleus of the thalamus, which projects in turn to the whole frontal neocortex. A diffuse projection to most of the frontal area is all that is needed to activate appropriate behavioral schemata. A denser projection from the dorsomedian nucleus is received by the orbitofrontal region, and it sends association fibers (by way of the uncinate fasciculus) back to the piriform cortex surrounding the amygdala. Thus, the goal selection circuit is able to make sure that desires are attached to the right objects.

Internalizing the spatial structure of the world. Even telesensory animals internalize a map of their territory. But their map plays very specific roles in generating complex, “hardwired” instinctive routines in telesensory animals. However, much of what is hardwired instinct in telesensory animals is learned by subjective animals from the environment. That is partly what makes the subjective level of neurological organization possible. As we have seen, what makes learning so much more important in subjective animals is a form of reproductive causation contained in individual brains with spatial imagination by which behavioral schemata evolve by reinforcement selection. (A similar mechanism has been described by Edelman, 1987, 1989, under the name of "neural Darwinism".)

The basic structure of the forebrain systems is set up in mammals by the biological behavior guidance system during embryological development, including the circuits of 2-D arrays that constitute the basic subsystems of the subjective animal behavior guidance system. But more neurons are created than are needed, and many neurons can make synapses more or less randomly with certain other neurons. The basic circuits line up 2-D arrays so that sensory input is registered in a way that can be used in generating behavior, and correspondingly, the mechanisms of the behavior generator are set up to make use of such sensory input in guiding behavior. But the specific neural connections needed to analyze and store sensory input in the most useful ways are lacking, and genetically prescribe behavior in response to sensory input is little more than reflexes built into in the behavioral output system and more or less random combinations of them.

Behavioral schemata in the behavioral output system evolve by a contained form of reproductive causation. As random variations on behavioral schemata are tried out, there is a natural selection of those that are successful in some way by a reinforcement that works through the memory circuit.

Though the memory circuit is depicted in the functional diagram as the basic structure of the sensory input system, it is realized in the brain in such a way that it is able to work the same way on neurons throughout the neocortex, including the behavioral schemata and body image in the anterior as well as the local image in the posterior neocortex. When some set of neurons is successful in some way, the memory circuit ties those neurons together in a memory group. That is, it instructs them to form synapses with one another so that if any crucial group of those neurons fire, the whole group will fire together. And with their synapses with one another strengthened, the whole group is more likely to be included as parts of other random variations on behavioral schemata.

Let us call such groups of neurons, which may be in the same 2-D array or in many different 2-D arrays, “memory groups.” Though the formation of memory groups depends on the memory circuit, once they are formed, they can be called up without any help from the memory circuit. The newly formed synapses among the neurons will make them act as a group when aroused by other neurons in the neocortex.

This increase in their likelihood of firing together again as a group is a form of natural selection of the group. It call it “reinforcement selection,” because the criterion for forming memory groups is, in mammals, the kind of desire satisfaction behaviorists were actually referring to in talking about reinforcement. The memory circuit is an ancient structure that includes the seat of desire, sometimes called the “limbic system,” and thus, success in satisfying desire in some way or other can easily be what triggers the formation of memory groups. In the case of learning behavioral schemata, success can easily be detected, for as we shall see, it is just success in internalizing some aspect of the world.

Mechanisms for identifying objects from the analysis of sensory input evolve in a similar way in the sensory input system. At the beginning of this phase of neurological development, groups of neurons respond to sensory input more randomly, and the memory circuit internalizes detailed structures that enable the sensory input system to recognize objects in sensory input and discriminate among them.

Telesensory input in any modality, such as vision or hearing, is registered in many different 2-D arrays. Those arrays may be determined to respond to them in different ways by the biological behavior guidance system, but the memory circuit, using built in criteria for success, can tie neurons together that are regularly active in processing sensory input in one way in one 2-D array with other neurons that are regularly involved in processing the same input in another way in another 2-D array. Thereafter, when sensory input is recognized in one 2-D array, such association fibers make it more likely that the input will also be recognized in the other 2-D arrays. Thus, processing in the various telesensory images work together to disambiguate sensory input.

At a later stage of neurological development, when mechanisms for recognizing objects of certain kinds have been established, this mechanism can also be used to identify particular objects. Different objects of similar kinds can be distinguished by tying a general memory group together with additional neurons in various 2-D arrays that are distinctive of it in a new memory group.

When new sensory input causes patterns of neuronal firings in many different 2-D arrays of the sensory input system that conform to such a memory group, the memory group is activated, and the sensory input system settles into equilibrium. (Since these areas of neocortex are all coordinated by the thalamus, such a settling into equilibrium may be what causes the distinctive “gamma oscillations” that are detected by EKGs when objects are recognized.)

For our purposes, what is most relevant about this contained form of reproductive causation is how the evolution of behavioral schemata internalizes the spatial structure of the world as the structural cause of spatial imagination. Though the behavioral schemata are certain groups of neurons in the frontal neocortex that the behavior generator uses to issue motor commands from the body image, what evolves are neural connections throughout the neocortex, because motor commands must be generated in relation to sensory input. These groups of neurons are the “organisms” (or primary structures) that evolve, because they are what go through reproductive cycles and have both essential structural effects. Random variations on them are naturally selected by success in reproduction, though in this case reproduction occurs when they generate overt behavior and it is reinforced through the memory circuit.

The basic schema has the part-whole complexity required of an organism that can evolve, since it is made up of motor commands to different parts of the body as well as different sequences of such sets of motor commands in time. Thus, many varieties of the basic schema are possible.

These schemata also do both kind of work that are required for organisms to evolve. Their non-reproductive work is the behavior they generate in relation to sensory input when they are firing. And they reproduce when the groups of neurons involved are signaled to strengthen and extend their synapses, that is, are reinforced for working together in the various circuits of 2-D arrays in a way that satisfies desire.

Thus, behavioral schemata evolve gradually, starting off simple, uniform and weak, and becoming complex, diverse and powerful. The ecological niches to which they adapt are all the various situations in which some special kind of behavior in response to sensory input is needed to satisfy a desire, that is, are reinforced.

Memory groups for identifying the telesensory images for situations in which behavior is reinforced are part of the selected behavioral schemata, that is, like discriminative stimuli. But since it is a faculty of spatial imagination, connections are also established between telesensory images and behavior that work the other way, so that when the behavior is generated covertly, telesensory images representing its effects are called up from memory.

In order to construct even a local image, the telesensory input must be registered in a way that indicates the bodily condition at the time, such as the direction the head and eyes are pointing when visual input is registered. That is a regular relationship in any given local scene viewed from a certain location, and thus, the memory circuit can establish their neural connections as a memory group. But in order for them to serve as a local image that can be recalled from memory, it must be possible for the behavior generator to use the combination of telesensory images recorded in memory as a local image to anticipate what telesensory images will occur when it behaves in various way, and that is a result of the evolution of behavioral schemata in the behavior generator.

Starting with whatever behavioral schemata are built into the behavior generator genetically, such as standing up, walking, focusing eyes together on an object, behavioral schemata for more complex or more precisely controlled behavior can be acquired by reinforcement selection of random variations on them. But since telesensory images are recorded in the local image according to the bodily condition at the time, schemata for generating those bodily conditions become labels for calling up those telesensory images in imagination. Thus, as behavioral schemata evolve, the subjective animal learns the motor commands to use in moving its head and body in order to make an object that appears to the right visual field move to the center of the visual field.

Though local images vary with the local scenes they represent, the same behavioral schemata for calling up particular telesensory images from them will work for them all, because bodily movements have similar effects in all situations. The behavioral schema that evolves for that function becomes, in effect, the structure for recording all local images, and the covert behavior for generating bodily conditions become labels for calling up the telesensory images in different directions. Thus, the evolution of behavioral schemata internalizes an aspect of the spatial structure of the world.

Once the ability to construct and recall local images has been acquired, much the same kind of process will internalize the structural causes needed to link them in sequences as a map of its territory (assuming that the cingulate gyrus contains a mechanism that can link memory groups in sequences). Given that behavioral schemata for locomotion and turning in relations to perception have been acquired, the key to spatial imagination is recording and recalling entire local images in a way that corresponds to such behavior.

Starting from a certain local scene in the territory, the effects of locomotion and turning on the local images encountered are determined by the spatial structure of the actual world. Thus, assuming that the memory for sequences of local images (in the cingulate gyrus) receives input about its overt locomotion and turning, its neural connections to the resulting changes in local images become labels for recording and recalling local images as a map of the territory. Using those behavioral schemata to generate covert locomotion and turning in relation to a given local image would, therefore, enable the subjective animal to explore the map of its territory.

Once again, however, the same kinds of behavior, turning and locomotion, work much the same way in any local image of the territory. Thus, as these behavioral schemata evolve, the memory for sequencing local images (and for shifting from one sequence to another when the body turns in a different direction) acquires labels that are used for every local image. That is a general understanding of the structure of space in terms of the effects of motion, and it informs even the local image, that is, enables the subjective animal to see its telesensory input from objects in the local scene as spatial relations that can change by motion. For example, as it learns to register local images according to turning, it learns that turning far enough brings it back to the same direction, and it can come to see how it would have that effect even in the local image.

The capacity to acquire structural causes from the environment eases the burden on the biological behavior guidance system to provide structural causes, but once the basic structure of the mammal’s higher level of neurological organization had been selected, evolution by reproductive causation would provide the additional structures needed to make this learning mechanism more efficient and complete.

The representation of the local scene is, in effect, a representation with polar coordinates, whereas the memory map of all the salient objects in the territory uses, in effect, Cartesian coordinates. This translation between polar and Cartesian coordinates is mathematically too complex to be provided genetically, but it can be acquired from experience. As the mammal experiences the consequences of moving in different directions from the local scene and finds the same objects showing up as a result of different combinations of bodily movements, behavior schemata for turning and moving in each direction evolve, so that later they can be used by the behavior generator as labels (in the anterior cingulate) to switch from one sequence of local images to another in exploring its subjective map. The mammal discovers, for example, the direction in which the body winds up moving as a result of various combinations of bodily movements, such as turning, backing up, rolling over, and the like, and so those combinations become packaged as behavioral schemata, or possible intentions, to move in certain ways in local scenes. They provide the translation from the "polar coordinates" of the local image to the Cartesian labels of the memory map. Only when a young mammal has learned the effects of turning and locomotion in the local scene is it able to start using the memory circuit to construct its own 3 .D memory map of the territory.

The origin and detailed structure of the mammalian brain. Assuming that much of the detailed connections among neurons can be acquired from the structure of the world by experience, or learning, all that is needed for telesensory vertebrates to try out the higher level of neurological organization required for a subjective animal system of representation is a random variation that sets up the basic circuits depicted in the functional description of the behavior guidance system. By considering the structures of the non-mammalian and mammalian vertebrate brains, we will see how it can be accomplished by a relatively simple, albeit radical, the random variation. That description of the basic structure of the mammalian brain also reveals the detailed neural mechanisms that serve the various functions in the subjective animal behavior guidance system.

In the non-mammalian vertebrate brain, as we have seen, the three subsystems serving the three subfunctions of the animal behavior guidance system are distributed to three anatomically distinct regions of the brain, the segment of nervous system rostral to the spinal chord, which connects the brain to the body. Those regions are the forebrain, midbrain and hindbrain.

Any behavior guidance system, as we have seen, must register sensory input from the world, select from among incompatible kinds of behavior, and generate the kind of behavior chosen. In the vertebrate brain, sensory input is registered in the midbrain, selection among incompatible kind of behavior is mainly the responsibility of the forebrain, and behavior is generated by the hindbrain. Connections between the midbrain and hindbrain enable them to serve as the telesensory animal system of representation.

The transformation of the non-mammalian into the mammalian brain is often described as the centralization of functions in the nervous system. That is, the three subfunctions of the animal behavior guidance system, which are parceled out to the three anatomically distinct sections of the non-mammalian brain, are all served by one of those sections in mammalian brains, namely, by the forebrain.

It is obvious that the mammalian forebrain serves the output subfunction, since motor output is generated directly from the neocortex, a distinctively mammalian structure in the forebrain. (Motor output from the hindbrain, which generates motor output in non-mammalians, is fully under its control.) Muscles throughout the body are controlled by a somatotopically organized 2 .D array of neurons in the motor neocortex.

Although visual input is already received by the forebrain in non-mammalians (along with the optic tectum in the midbrain), it is joined in mammals by well defined relays to the neocortex for auditory and somatosensory input (all three via nuclei in the thalamus).

Since the subfunction of selecting goals for behavior is already contained in the forebrain, it is apparent that the mammalian forebrain is using its sensory input to generate motor output, thereby serving all three subfunctions. Hence, it is the mammal's entire animal behavior guidance system.

The shift of all three subfunctions from the three distinct parts of the non-mammalian brain to the forebrain resembles the evolution of the vertebrate brain from brainless chordates: just as the rostral end of the chordate neural tube became a brain that took over the control of behavior from reflexes located throughout the neural tube, so the mammalian forebrain takes over the control of behavior from the midbrain and hindbrain. The midbrain and hindbrain structures are still there, but they are slaves to the forebrain (and are omitted from the mammalian diagrams unless they play an essential role).

Furthermore, the neural connections among the subsystems in the mammalian brain are just what would be expected of an animal system of representation with spatial imagination. We have seen functionally how the subjective animal system of representation requires four subsystems (the local image, body image, behavior generator, and memory), and the simplest and most convincing way to show how their functions are served by structures in the mammalian forebrain will be to describe how those mammalian structures evolve from simpler mechanisms in the non-mammalian forebrain. The relevant structures of the vertebrate brain have already been described (see Stage 5. Telesensory animals: Structure of the non-mammalian vertebrate brain).

There are, as already mentioned, two kinds of changes in the non-mammalian forebrain that result in mechanisms for the subjective animal system of representation — the evolution of the neocortex, and a restructuring of the thalamus that redirects the non-mammalian forebrain output back to the (telencephalon of the) forebrain (by way of the thalamus) to form the complete circuits of its higher level of neurological organization. The first change occurs in the telencephalon of the forebrain and the second in the diencephalon.

The neocortex evolves from the integration of the DVR and dorsal cortex, the two main telencephalic targets of thalamic nuclei in reptiles. During embryological development in mammals, cells in the telencephalon that would become the DVR in reptiles migrate to the dorsal cortex (the extended flap of neural tube at the diencephalon) and lay themselves out in the dorsal cortex against the outer surface of the mammalian telencephalon. The result is the six layers of cells distinctive of mammalian neocortex. (Compare the diagram of the reptilian brain with that of the mammalian brain.lxvii) The evolution of the neocortex adds to the telencephalon a somatotopic representation of the body (the body image) and all the telesensory images that make up the local image.

The thalamus is restructured so that it redirects the non-mammalian forebrain's three kinds of output back to the telencephalon, and this results in the creation of three circuits in the mammalian forebrain. Each circuit is a pathway of neural projections that includes both the thalamus and the neocortex along with special structures that make them different from one another. And each circuit serves one of the basic subfunctions of the animal behavior guidance system. The sensory input circuit serves as local image with the memory in the functional diagram. The behavioral output circuit combines the systems labeled body image and behavior generator in the functional diagram. The third circuit is the affective system, for selecting goals of mammalian behavior, which attaches desires to objects in the local image by activating dispositions in the behavior generator.

Since the neocortex and thalamus are what are linked by the three circuits, these two main changes are connected. Each of the areas of neocortex and nucleus of the thalamus is on roughly the same level of neurological organization as each of the basic systems making up the telesensory animal behavior guidance system, and thus, when they are linked in a three different circuits, each serving one of those subfunctions, there is obviously a higher level of neurological organization. But the best way to see how this basic structure is tried out is to start with the change in the thalamus that gave the neocortex a somatotopic representation of the body to serve as the behavioral output system of the subjective behavioral output system.

The body image.Motor output is generated from the body image, a region of the neocortex that is somatotopically organized. It receives somatosensory input from all parts of the body and it generates the motor output controlling all parts of the body. Like the local image in the posterior cerebrum, the body image is a region of neocortex located in the anterior cerebrum. But somatosensory and motor neocortex represent the body like a picture (or, rather, several pictures), and a somatotopic organization is such a highly improbable mechanical order that the behavioral output system is a good example of a complex structure that seems unlikely to be tried out as a random variation by the mechanism of embryological development. But it most come from somewhere.

The image of the body in the neocortex cannot come from either of the geometrical structures from which the neocortex evolved, because neither the DVR nor the dorsal cortex have a somatotopic organization. But telesensory animals needed such a somatotopic representation of the body in order to even out motor commands to muscle groups in each region of the body so that whole body behavior would be coordinated. That requires the command neurons to be related spatially to one another corresponding to spatial relations among the parts of the body they control, and that was the function of the cerebellum.

Even before reptiles, there was a rough somatotopic organization in the cerebellum (the archicerebellum), but the evolution of legs required a more distinct somatotopic organization. As mentioned above, it is found in a new region of the cerebellum (the paleocerebellum) and in the red nucleus to which it projects in the midbrain in order to affect motor commands to the limbs.

There is a further development of a similar kind in the mammalian cerebellum. Yet another region is added to the cerebellum (the neocerebellum). The mammalian cerebellum projects to the red nucleus and (joined by a projection from the red nucleus) to the motor neocortex (relayed in both cases by a new nucleus of the thalamus, the ventral lateral nucleus). In other words, the red nucleus now sends motor commands to the limbs by way of a somatotopic representation in the neocortex. (See diagram of the behavioral output system.) This relay of its output to the motor neocortex required a new nucleus in the thalamus, and that may have been the original random variation that is responsible for both the reorganization of the thalamus and the neocortex.

Not only does it locate a somatotopic behavioral output system in the neocortex, but it is also the source of the somatotopic organization of somatosensory input to the neocortex (which is also relayed to the neocortex by a new thalamic nucleus, the ventral posterolateral nucleus).lxviii In primitive mammals, such as the hedgehog, somatosensory input and motor output share the same body image in the neocortex, and only later do their images come to occupy adjacent areas of neocortex across the central sulcus.

The local image.The telesensory images making up the local image are on the same level of part-whole complexity as the body image. Both are regions of neocortex receiving highly organized 2-D projections from specific nuclei of the thalamus. As in earlier vertebrates, telesensory input is relayed to the telencephalon by nuclei in the thalamus. Visual input is relayed by the lateral geniculate body to the occipital neocortex, and auditory input is relayed by the medial geniculate body to a region of the temporal neocortex. But the evolution of the neocortex provides a more powerful mechanism for its analysis than in telesensory animals. (See the diagram of the local image.)

Regions of neocortex all have a similar structure. Thalamic neurons send axons in ordered, 2 .D arrays to certain 2-D areas of neocortex where they synapse with certain kinds of neurons (that is, with neurons in one or another of its six layers). And neurons in target areas of the neocortex send 2 .D arrays of axons to three kinds of targets in the forebrain: directly back to thalamic nuclei, to other neocortical areas, and to the corpus striatum and its special projection to certain thalamic nuclei (behavior generator). These connections are determined genetically, by instructions from the multicellular biological behavior guidance system. It is a good example of the more complex structures that can develop from the neural tube in deuterostomes: neurons in the thalamic nuclei and their neocortical targets are born with molecular labels by which they can somehow recognize their own locations in their own 2 .D array and seek out corresponding locations in other 2 .D arrays.lxix

In the case of telesensory images, all the 2 .D arrays in the thalamus and neocortex are usually processing sensory input from the same objects in the local scene at any given moment, but following genetic instructions to analyze it in different ways. With evolution by reinforcement selection, therefore, they can use the results of one another's analysis to confirm their own conclusions, thereby improving the efficiency of them all.lxx Jointly, they are a subsystem with a 2 .D representation of the object at a distance.

The local image is, however, a more encompassing 2-D representation of the current scene, which includes all the currently perceivable objects relative to the body. The local image is constructed by an interaction between the body image and specific telesensory representations. The local image is constructed in a region of neocortex (the inferior parietal lobe) adjacent to the visual and auditory analysis areas, on one side, and the body image, on the other, and it receives association fibers from both sides. (See diagram of the local image.) The image of the body in the motor and somatosensory neocortex projects association fibers providing information about the current bodily condition (its stance and motion), and the parietal area uses it to locate objects of telesensory images in the scene relative to the body by taking account of the direction in which the head and ears are pointed when they are received.

The eyes are, however, a special case. Their fixations are controlled by the frontal eye fields (an area of frontal neocortex, anterior to the motor cortex, which we are counting as part of the behavioral output system). The frontal eye fields also report their oculomotor commands to the inferior parietal lobe (via association fibers), where an interaction with the visual neocortex (in the occipital area) constructs a larger representation of the scene (the local image) from the visual images that show up in each fixation.lxxi (See diagram of the local image.) The already constructed local image guides the fixations of the eyes to objects in the scene; that is apparently the function of a highly unusual, ordered 2-D projection of fibers to the frontal eye fields from the thalamic nucleus (pulvinar) that serves the inferior parietal area.lxxii The local image is not, therefore, just a collection of telesensory images, but an ordering of them that indicates the direction and distance of each from the body, or what serves as representation of the current local scene.

Touch is a new sensory modality, which depends on a certain kind of somatosensory input to the body image. As we have noticed, somatosensory input is relayed (by the posterolateral nucleus of the thalamus) to the somatosensory neocortex (across the central sulcus from the motor neocortex), where reports from joint and muscle receptors supplies feedback about the effects of motor commands from the body image. But it is also, in effect, a new sensory modality, because input from skin receptors (of various kinds) is combined with the representations of the scene and the body (in the superior parietal area served by the lateral posterior thalamic nucleus) to yield information about other objects in the current scene (though this does not yield much information about them except location until the evolution of manipulative animals). (See diagram of local image.) Since the objects are distinct from the body, but located not at a distance for it, touch might be called an "extrosensory modality."lxxiii

The evolution of the neocortex, in sum, accounts for one part of each of the two basic subsystems of the subjective animal system of representation, the sensory input and behavioral output systems. Almost every area of neocortex receives a projection from one or more thalamic nuclei (and sends fibers back), but the body image is located in the anterior neocortex, and the 2 .D telesensory images of the objects in the scene and their combination as a local image is located in the posterior neocortex. But these regions of neocortex act on the thalamus in two different ways, each of which makes the neocortex a link in a complete circuit. The rest of each circuit is the other part of the sensory input and behavior output systems represented in the functional diagram of the subjective animal system of representation, and that is the part of each circuit that is provided by the other major change in the mammalian forebrain, the redirection of the output of the non-mammalian forebrain back to the telencephalon by relays in the thalamus. (The same also holds for the goal selection system, the third part of an animal behavior guidance system, as we shall see.)

We have seen that there are three pathways of output from the non-mammalian forebrain: the ancient olfactory pathway, the striatal pathway, and the hippocampal pathway. And each is responsible for a new, complete circuit in the mammalian forebrain. Indeed, the functions are parceled out to these circuits according to the three subfunctions of any behavior guidance system.

The striatal pathway becomes part of the behavior generator which works together with the body image to serve as the behavioral output system.

The hippocampal pathway becomes the memory which works together with the local image to serve the sensory input subfunction of mapping the territory.

And the olfactory pathway becomes the goal selection system which works together with both frontal and posterior areas of neocortex to serve the subfunction of selecting goals,. We will put the olfactory pathway aside for now and take it up only after detailing the subjective animal system of representation, because the subjective animal behavior guidance system is what results when olfactory pathway is added to the subjective animal system of representation. Let us begin with the hippocampal pathway and how memories are recorded.

The memory.The mammalian memory is a forebrain circuit that results from redirecting the hippocampal output of the non-mammalian forebrain back to the telencephalon by way of another new thalamic relay (the anterior nucleus) in the diencephalon. Its target is, however, a new region of neocortex, the cingulate area, which runs parallel to all the other areas of the neocortex at the medial extreme of the neocortex (including the local image, body image, and other regions of frontal neocortex where behavioral schemata are located. See diagram of the memory.) This provides a new, complete circuit, because association fibers connect the cingulate area with all the areas of neocortex running parallel to it, and those areas all have association fibers to (a staging area in the temporal lobe that projects to) the hippocampus. Since the hippocampus receives information about the "images" in 2-D arrays throughout the neocortex, it is what enables the mammalian brain to learn from experience with the three dimensional structure of the world how to use the input about the body condition (association fibers from the behavioral output system to the parietal cortex) to construct the representation of the local scene and how to label such representations by their locations relative to one another in three dimensional space as it forms new memory.

The basic mechanism involved in the formation of memories is the strengthening of synapses of association fibers connecting sets of neurons in various regions of the neocortex that are firing at the time, so that later, when enough of them fire together again, it makes the others in the group fire as well. Although synapses are strengthened anyway among 2-D arrays in nearby areas of neocortex that are closely interconnected,lxxiv the hippocampus-cingulate circuit connects, as memory groups, neurons from all areas of neocortex that are active at the moment.lxxv This connects images of the same object from different sensory modalities as the same object and images of various objects in the current scene as a local image so that they can be called up together as units. But it is necessary to have input about the current bodily condition to label telesensory images by the behavior involved in perceiving them in the scene. That is provided by association fibers from the behavioral output system to the inferior parietal neocortex, and if input from the bodily condition is not what is combined in the memory groups for the local image, it must be the relevant groups of neurons of the behavioral output system itself.

Given how the memory system (the hippocampus-cingulate circuit) works, it is required to form such cortex-wide memories. But it is not involved in recalling memories. Recalling memories is simply a matter of making the whole group fire together by enough of its members firing for some reason.lxxvi

Indeed, at an earlier stage of embryological development, as mentioned above, the memory circuit is responsible for acquiring the behavioral schemata by which overt inquisitive behavior can construct local images and similar covert behavior can extract information about the locations of objects in the local science from local images called up from memory. The memory circuit provides the “natural selection” for a contained form of reproductive causation in which the “reproducing organisms” are connections among neurons serving as behavioral schemata, neurons representing the bodily condition, and neurons serving as telesensory images, and these connections evolve as parts of schemata that the behavior generator can use, as inquisitive behavior, to construct local image, or as covert behavior, extract information about them. The correlations between telesensory input and bodily condition that hold for objects of every kind in any local scene depend on the structure of space (and the structure of the body driven by the brain), and the memory circuit enables the brain to acquire the general connections between cells in the local image and body image so that behavior schemata for constructing and using local images can evolve by the natural selection of a reinforcement that strengthens the connections when they are successful, for example, when the animal can find objects it desires in the scene. Thus, the structural cause of the capacity to record and use local images is internalized from the structure of the spatiomaterial world by a form of reproductive causation that occurs as a later phase of the process of the embryological development of the brain.

There is evidence, by the way, that the schemata for this kind of behavior is derived from experience. When human subjects are fitted with glasses that reverse right and left or up and down in the visual field, there is, after a long period of awkward attempts to compensate, a dramatic change in which subjects report that everything "suddenly" seems oriented in the "right" direction again. As the memory circuit lays in new connections for behavioral schemata to construct and use local images with the reversing glasses and they take over, one's sense of direction changes.

The memory circuit also has a built-in structure that makes it possible to connect local images in sequences corresponding to the direction of locomotion and turning relative to them, though linking them in such sequences depends on the cingulate neocortex functioning in an additional way. When the cingulate neurons in a memory group fire, so do the associated images in the adjoining regions of neocortex, and vice versa. The means that the cingulate neocortex is in a position to determine the local images called up in sensory input system. Thus, in order to serve as the memory for spatial imagination, all the cingulate gyrus needs is the capacity to link local images together in long sequences and to be able to switch from one such sequence to another when their local images overlap.

The posterior cingulate gyrus is in a position to serve as the memory for spatial imagination, because the posterior cingulate receives input about the bodily condition, overt and covert, from the anterior cingulate gyrus. The anterior cingulate gyrus is connected to the body image and the behavioral schemata in the behavior generator in a way that is similar to the connection between the posterior cingulate gyrus and the local image, except that the influence runs the opposite direction. The body image and behavioral schemata project to the anterior cingulate gyrus, and the anterior cingulate gyrus is an (agranular) motor neocortex like the body image and behavioral schemata, except that it has not effect on overt motor output and projects to the posterior cingulate gyrus.

Since the body image contains information about how the body moves and turns overtly in the scene, the connections it makes with the posterior cingulate gyrus would become labels that are recorded with the sequences of local images. And since the behavioral schemata contain the same kind of information about covert behavior, and it is projected to the posterior cingulate gyrus in the same way, those connections can be used as labels to call up the local images according to how it move and turns covertly in relation to the images called up in memory.

As sequences of local images become richly interconnected, the mammal acquires a map of its territory by which it can travel almost any route. It is the structure of space that ensures that such interconnections of sequences can accumulate without contradictions. This internalization of the structure of space is an example of the a contained form of reproductive causation that takes place in neurological development as a result of reinforcement selection. The memory labels required for constructing and exploring memory maps are part of the behavior schemata that evolve gradually toward greater efficiency in satisfying desires, in the first instance, getting the animal where it wants to go.lxxvii

The behavior generator.In reptiles, the DVR is the main source of input to the striatum (which is one pathway of non-mammalian forebrain output to the midbrain), and thus, since those DVR cells migrate in mammals to the dorsal cortex and combine as the neocortex, the neocortex becomes the main source of input to the striatum (called the corpus striatum or basal ganglia). In fact, all areas of the neocortex project to the corpus striatum, including the local image, the body image, behavioral schemata in the frontal neocortex, and the cingulate neocortex. But the output of the corpus striatum, which in reptiles was projected to the midbrain as motor commands, is mostly redirected in mammals back to the neocortex by way of a relay in the thalamus (the ventral lateral and ventral anterior nuclei). The targets of the corpus striatum are all in the frontal neocortex (in the anterior forebrain), including both the body image and the behavioral schemata. This new circuit is the behavior generator. But there are two channels through this circuit, which were not distinguished in the functional diagram except for the ability to generate behavior either overtly or covertly.

Part of the corpus striatum's output is relayed by the (ventral anterior) thalamus to regions throughout the frontal neocortex where the behavioral schemata are located. This part also projects to a region called the “premotor cortex” (an anterior part of Brodmann area 6), which is the behavioral output system for covert behavior. It also projects to the frontal eye fields, which controls the fixation of the eyes on objects in the local image.

The other part of the striatum’s output is relayed by the (ventral lateral) thalamus more specifically to the motor neocortex itself, the part of the body image that is responsible for overt behavior. This includes both the motor neocortex (Brodmann area 4) the supplementary motor neocortex (an area of neocortex adjacent to the motor neocortex which modifies motor commands directly, which is part of Brodmann area 6.)

The motor neocortex (the body image from which overt behavior in generated) also receives a projection from the ventral lateral thalamus that relays the output of the cerebellum (where motor commands are evened out spatially and temporally in a detailed way). The motor commands actually sent to the body depend, therefore, on the cerebellum as much as the circuit through the corpus striatum and ventral lateral thalamus. But the cerebellum is controlled by these circuits through the striatum and thalamus, because the cerebellum follows motor commands from the body image, including both parts, Brodmann areas 4 and 6. (The premotor commands, a part of the body image that generates covert behavior, enables the cerebellum to anticipate the next overt motor commands.)

The corpus striatum has just the connections required of a subsystem whose function is to generate behavior in relation to the object at a distance. It receives 2 .D arrays of fibers from all areas of the neocortex, including the local image in the posterior neocortex, on the one hand, and the behavioral schemata and body image (both premotor and motor areas) in the anterior neocortex. But it projects only to the behavioral schemata and the body image in the anterior neocortex. (See diagram of the behavior generator: overt behavior.)

The local image sends fibers almost exclusively to a distinct part of the corpus striatum called the caudate nucleus. The caudate nucleus apparently compiles an image of the object situated in the current scene from all parts of the posterior neocortex, because 2 .D arrays of posterior neocortex that are connected by association fibers tend to converge on the same areas of the caudate nucleus.lxxviii

Similarly, the body image send fibers almost exclusively to a distinct part of the corpus striatum, called the putamen. The putamen compiles an image of the body from all areas of the anterior neocortex, including the frontal areas containing behavioral schemata and the body image, for it merges 2-D arrays from parts of neocortex that are closely connected by association fibers. With behavioral schemata contained in the frontal neocortex, the putamen has instructions by which to generate a specific kind of behavior (depending on which desire predominates at the moment).

A third distinct part of the corpus striatum, called the globus pallidus, combines the compiled image of the body with the compiled image of the object according to the selected schema to produce detailed motor commands for each part of the body as needed to adjust its behavior to the object in space.lxxix The globus pallidus can generate behavior, because it projects by way of nuclei in the thalamus to areas of premotor and motor neocortex that are responsible for motor commands to all parts of the body.

For the animal system of representation to have a spatial imagination, however, the behavior generator must be able to generate motor commands in relation to objects in the scene without the body actually acting on them. And the corpus striatum does, indeed, have connections that make it possible to generate behavior covertly rather than overtly. There are two distinct channels by which the corpus striatum projects to the thalamus (and from there back to the neocortex, which completes a circuit because of the cortex’s projection to the corpus striatum). (Both originate in the internal segment of the globus pallidus, the third part of the corpus striatum, where both the local image and body image are represented).

One channel (by way of the ansa lenticularis) projects to the ventral anterior nucleus of the thalamus which relays it to the premotor and other frontal areas of neocortex where behavioral schemata are contained. These areas of neocortex project in turn to the anterior cingulate gyrus, whose connections with the posterior cingulate gyrus enable covert behavior to affect the sequences of images in memory.

The other channel (by way of the lenticular fasciculus) is relayed by the ventral lateral thalamic nucleus to the supplementary motor neocortex, which lies alongside the motor neocortex and generates overt behavior. (The ventral lateral nucleus also relays the detailed motor instructions from the cerebellum and red nucleus, but that is a later effect of this circuit for overt behavior through the striatum and thalamus, because its motor commands are what the cerebellum uses to work out the detailed motor commands.) These areas of the body image also project to the anterior cingulate gyrus, where they can establish labels for the sequences of local images in spatial imagination.

Both channels of the are active when behavior is overt. The covert route is never suppressed, because it is the circuit that contains the behavioral schemata and uses them to set up complex, multi-step motor commands in advance of acting. But when the channel to the motor neocortex is suppressed, behavior is generated covertly, as imagination, because the anterior cingulate gyrus still receives the projection from the behavioral schemata and premotor cortex. That is enough information about locomotion and turning to call up memories of local images by the labels that were established when both overt and covert parts of the body image were being projected to it.

The subjective animal’s behavioral output system has, therefore, two body images. Both are used for generating overt behavior, but one can be used for generating covert behavior. Covert behavior is the motor output in the cingulate gyrus, which acts, not on the actual world by way of the body, but on the world as represented in memory by way of covert behavior. Since the anterior cingulate gyrus projects to the posterior cingulate gyrus in much the same way that the motor neocortex (and associated areas) project to the parietal and sensory neocortex containing the local image, it is not surprising that the memory circuit can register images according to the behavior that causes them, that is, by labels. Nor is it surprising that covert behavior can use those labels to call up the images from memory as imagination.

The difference is that telesensory images are registered according to input from the overt bodily condition so that they become a local image, which can be recorded as a unit in memory, whereas local images are registered according to input from the overt locomotion so that they become linked in a sequence as a map of the territory. One occurs in the non-cingulate region of the neocortex, the other occurs requires the cingulate area. Likewise, when a local image is remembered, its individual telesensory images can be called up by input from covert behavior in the non-cingulate neocortex, whereas other local images connected to it can be called up by input from covert locomotion in the cingulate gyrus.

This parallel suggests that labels can be established in both cases by the memory circuit working as a form of reinforcement selection for the evolution of behavior schemata. The labels are simply connections of the behavioral schemata with the rest of the brain that are reinforced as parts of those schemata when behavior is overt, and thus, since the behavioral schemata can be used to generate the same behavior covertly, they automatically have labels by which to call up the relevant images from memory.

What is crucial to internalizing the structure of space as spatial imagination about the consequences of locomotion and turning is the capacity of the cingulate gyrus to link complex memory groups in sequences. That is what the non-cingulate neocortex lacks. Sequences of images are not needed to construct local images, because they can be accessed in any order by the appropriate bodily condition, turning the head, eyes, etc. But it is the use of sequences, and their being projected to the behavior generator (via the caudate nucleus of the corpus striatum) as time passes, that makes it possible to imagine locomotion and motion. And that is the key to their being an understanding of the structure of space. This is a capacity to see the actual locations of objects against the background of what is possible by motion, which is to understand the structure of space.

The subjective animal’s map of the world becomes an understanding of space simply because the same kinds of locomotion and turning have the same kinds of effects relative to any set of local images. That is because the world from which those sequences were recorded is a world of objects that are actually related by being contained by space. Thus, experience with the world gives the subjective animal is understanding of the general effects of the motion and direction of motion of an object on its spatial relations to other objects. It is, of course, an intuitive understanding, not a linguistic understanding. But it is nonetheless an understanding by which it can foresee what will happen and understand what has happened.

More generally, however, the power of the memory circuit as a form of natural selection on behavioral schemata working by the reinforcement of synapses to form memory groups is broader. Assuming that during the process of development, the whole range of behavioral schemata that are possible because of the genetically provided basic schema are tried out, gradual evolution will occur, and the schemata will becomes increasingly powerful. Each behavioral schema will come to be as effective as possible in controlling some relevant condition, that is, generating behavior is some kind of situation to satisfy desire. That is actually the result of the gradual evolution of that schema, since it is made up of different motor commands as parts, and it is by alterations in them that variations are tried out. But different behavioral schemata will also be fit together as harmoniously as possible as parts of behavioral routines that satisfy desire. And new schemata will be added as long as they control additional conditions that affect their reproduction. Thus, learning from experience that provides subjective animals with behavioral schemata for many kind of behavior. The schemata that serve as structural causes for spatial imagination is just the most important kind of behavior, given the nature of the world in which animal find themselves and their need to act on objects in space.

This theory of imagination as covert behavior offers a plausible explanation of schizophrenia. Hallucinations that are not recognized as hallucinations (usually auditory hallucinations) are the main symptom of schizophrenia. They make it difficult for schizophrenics to tell the difference between fantasy and reality. It is known that schizophrenics often show a lack of activity in the frontal neocortex when hallucinating (apparently due to an unusual level of the neurotransmitter, GABA, in the region). Those areas of neocortex contain the behavioral schemata that control the anterior cingulate gyrus, whose effect on the posterior cingulate is to call up images from memory, and thus, it is possible that schizophrenia is a condition in which covert behavior is generated without control by behavioral schemata in the frontal neocortex. Since the images are not called up by activating some behavioral schema, as in normal behavior and imagination, they are not part the process of carrying out an intention, and thus, they seem to originate from the world, that is, to be real.

The goal selection system.Not only does reproductive causation in neurological development require reinforcement, but once animals have acquired a map of the territory and an understanding of the structure of space, they still need a mechanism to choose which goal to pursue in relation to which objects. These functions are served by the redirection of the third output of the non-mammalian forebrain back to the telencephalon. The redirection of the olfactory pathway back to the telencephalon makes it the goal selection system of the mammalian behavior guidance system.

The olfactory pathways involve, as described in the non-mammalian vertebrate brain,lxxx the amygdala and its many connections with the hypothalamus (and septum). This is still the seat of desire in mammals. The amygdala is mainly responsible for arousal, fear and anger, whereas the hypothalamus is responsible for hunger and sexual desire.

In mammals, the output of the amygdala (and indirectly the hypothalamus) is redirected by a thalamic nucleus (the dorsomedian nucleus) back to the behavioral schemata in the frontal neocortex (especially, the orbitofrontal area). This system selects which of the schemata for kinds of behavior that are built into the frontal neocortex (genetically or by learning) will guide the corpus striatum in generating behavior relative to the object in the local image.

The goal selection system is a complete circuit, for there are projections from the orbitofrontal area back to the amygdala (via the ancient piriform cortex surrounding the amygdala) which make sure that there is no confusion about which object is the object of desire.

Furthermore, the goal selection circuit is in a position to record and read desire labels with memory images. The amygdala has a projection to the hippocampus by which it can attach desire-labels to objects (for example, when the hypothalamus reports to the amygdala that an object satisfies hunger or sexual needs), and it can read the desire-labels already attached to objects, because it receives a projection from the staging area by which all areas of neocortex reach the hippocampus. (See diagram of the goal selection system.lxxxi)

A desire about an object sets a problem for the subjective animal system of representation to solve. Covert locomotion can, for example, explore its map and figure out a new route to an unperceived goal when its path is blocked or use its representation of the current scene to figure out how to approach or avoid some object. But a spatial imagination is only part of what is possible for a system that uses a somatotopic representation of the body to generate behavior by its parts, like the body image. Instead of having to evolve new instincts, it can learn new kinds of behavior involving different combinations of motor commands to parts of the body. And mammals can, in principle, figure out how to use such complex routines in the current scene by imagining variations on them and using memory images that are called up to anticipate whether the consequences will satisfy its desire. At least, this is the direction of subsequent evolution, as we shall see.

Acting. Once the problem is solved and a plan of behavior has been selected, the imagined behavior must be generated overtly. Covert behavior depends on one of the pathways through the behavior generator (the one from the corpus striatum via the ansa lenticularis to the ventral anterior nucleus of the thalamus and back to the frontal neocortex and premotor area). The behavioral schema that has been set up in imagination can be generated overtly by sending the same motor commands in relation to the perceived object along the other pathway as well (via the lenticular fasciculus to the ventral lateral nucleus back to the motor cortex).

What controls whether covert behavior is generated overtly or not is the centromedian nucleus of the thalamus. It projects to the putamen, the part of the corpus striatum that receives the schema from the frontal neocortex for the kind of behavior to be generated. The centromedian nucleus is located within the medullary lamina of the thalamus (separating its medial and lateral subdivisions), and since the thalamus is what synchronizes activity throughout the neocortex, that is a position from which it can to tell when an equilibrium is reached in systems throughout the brain. The intralaminar nuclei of the thalamus receive fibers from all parts of the neocortex, the brainstem, cerebellum and spinal chord.lxxxii (See diagram of the mechanism of acting.)

In the transformation of the non-mammalian into the mammalian brain, therefore, we find all three subsystems required for the subjective animal behavior guidance system (sensory input, behavioral output, and goal selection systems). Each involves a distinct circuit through the thalamus and neocortex, which allows neurons in multiple 2-D arrays throughout the circuit to be coordinated and aligned with one another. That puts each subsystem on a higher level of neurological organization than the non-mammalian vertebrate brain. Moreover, in the sensory input and behavioral output circuits we find both subsystems required according to our functional diagram for the subjective animal system of representation with spatial imagination (that is, local images and memory in the sensory input system and behavior generator and body image in the behavioral output system).

As we have seen, such a complex system is possible, at least in chordates (with the nervous system set up in a separate neural tube), because the higher level of neurological organization can be generated by a couple of relatively simple, albeit radical, modifications in the non-mammalian vertebrate brain, and neurological development involves a contained form of reproductive causation that internalizes the spatial structure of the world as the detailed structural causes of spatial imagination. Since the subjective animal behavior guidance system is also functional, we infer by the nature of reproductive causation that this stage of animal evolution in inevitable.

In the next section, we will consider the empirical evidence of the subjective animal stage of evolution. Though empirical confirmation of necessary truths is not necessary, it is relevant, because empirical evidence can falsify the foundation of ontological philosophy.

That will leave one final conclusion to be drawn, about the unity of consciousness in mammals.

It is appropriate to think of the mammal as a subject, since its spatial imagination gives it an understanding the structure of space and the regularities about motion and interaction for which it is responsible as an ontological cause. By seeing the actual locations of objects against the background of what is possible by motion, the subject sees the world as a world of objects in space. Even its own body is seen as located in space alongside other objects. But the mammal is not just a subject. It is a conscious subject.

When combined with the explanation of the basic nature of consciousness (that is, phenomenal properties as intrinsic essential natures of bits of matter), the structure of the mammalian brain also explains the unity of subjective consciousness, that is, why all the sensory qualia appear to a single subject at one time. There is a phenomenal appearance to the world of object in space and the body by which the subject acts in that world. Nor do the objects that subjective animals experience as located in space appear merely as object in space, because they also feel desires of various kinds about them. We will return to the unity of consciousness after considering the empirical evidence about the gradual evolution of mammals.

The gradual evolution of mammals.Though mammals are named after their distinctive mammary glands, their neocortex is an equally distinctive trait, and as suggested in discussing the structure of the non-mammalian vertebrate brain, it comes from a reorganization of the thalamus that transfers responsibility for all three subfunctions of the animal behavior guidance system to the forebrain. Since the neocortex derives from the reptilian DVR, mammals could not evolve until reptiles had evolved.

This reorganization had be tried out soon after reptiles, however, rather than later, for it is such a radical random variation that only the most primitive reptiles could continue to function. By the time reptiles had acquired as much power as possible for animals of their kind, their DVR would have become so essential to so many different kinds of behavior that such a radical random variation would probably have been fatal.

This obstacle is most obvious in the avian brain, where the DVR/striatum is divided by well-defined laminas into many separate regions serving special functions, such as controlling pecking and generating bird songs. Each part of the telencephalon generates behavior separately, by its influence on the midbrain and hindbrain. It is not that the advantages of complete circuits through the forebrain are entirely overlooked in birds. It does occur, but in a more limited way. As we have seen, birds evolved a mammal-like memory; the "visual Wulst" is part of a mechanism that resembles the mammalian memory circuit.lxxxiii But the avian brain lacks spatial imagination, because without a behavior generator that operates on a somatotopic representation of the body, it cannot acquire behavioral schemata from experience with the structure of space, but must rely on mechanisms supplied by the primary structure. Nor does avian memory include any sensory modalities beyond vision. It appears that the DVR-striatal circuit had become too complex by the time birds evolved for the DVR to migrate to the dorsal cortex and become a neocortex. Thus, birds have only a memory which is, at most, an advanced telesensory memory, that is, using a one-dimensional series of stimulus-response connections to get around in space as part of an instinctive routine for controlling specific conditions. But the visual Wulst is all birds need to record locomotor commands in relation to visual images and calculate directions and distances to unseen objects, for that enables them to find their way back to their nest, patrol at territory, and migrate with the seasons using visible landmarks.

Fossil evidence shows that mammals did evolve from primitive reptiles as our theory predicts. The last common ancestor of mammals and extant reptiles was 300 million years ago, about the time that reptiles first evolved. But there is still a problem with our explanation of mammalian evolution, which accidentalists often use to argue that mammals are not inherently superior, but merely different from, non-mammalian vertebrates: if mammals are more powerful, why were they dominated by dinosaurs for nearly 150 million years before the radiation of mammals? It seems that there would never have been a radiation of mammals, if it had not been for the impact of an asteroid. To answer this objection, we must consider the course of mammalian evolution.

Earth was dominated by mammal-like reptiles before dinosaurs evolved (about 225 million years ago). Mammal-like reptiles (therapsids) had tucked-in elbows and legs positioned more directly under their bodies, so they were better able to scamper over land than reptiles and probably fed on them. They used the energy, not only to stand upright, but also to supply a warm-blooded metabolism. Although some therapsids were as large as wolves, they were largely eclipsed by two-legged predatory dinosaurs about 225 million years ago.

But mammals continued to evolve during the age of dinosaurs. About 190 million years ago, mammal-like reptiles gave rise to a branch of primitive mammals (prototheria) which seem to have living descendants, the monotremes: the duckbilled platypus and the spiny anteater.

To judge by them, primitive mammals were warm-blooded and hairy. Although the platypus is still an egg-laying animals, it nurses its hatchlings and cares for its young, which is a radical innovation, considering that most reptiles have so little concern for their offspring that they sometimes eat their hatchlings when they come across them hungry. And monotremes have the mammalian neocortex (although it is not differentiated into as many areas and lacks the corpus callosum, the massive bundle of fibers that links the two hemispheres of neocortex in true mammals).

Later during the age of dinosaurs (about 135 million years ago), marsupials (metatheria) branched off from true mammals (eutheria), indicating that mammals had evolved all the basic traits that distinguish them from non-mammals during the reign of the dinosaurs, including live birth. But that did not enable mammals to replace dinosaurs in their energy-rich ecological niches, even though prototheria had about 55 million years and metatheria and eutheria had 70 million years to do so.

It seems, therefore, that what finally brought the age of dinosaurs to an end was not the inherently greater power of animals from a later stage of evolution, but an accident — the impact of a giant meteor or asteroid about 65 million years ago. The age of mammals might never have begun, if it depended only on the greater power of a higher level of part-whole complexity in the brain.

This accidentalist argument against the inherent superiority of mammals can, however, be answered when evolution is explained by reproductive causation. Incumbency in an ecological niche has an obvious advantage, and to deny that evolution is merely a matter of tracking changes in the environment is not to deny that catastrophic environmental change shakes out the natural kinds best suited for the more energy-rich ecological niches by forcing incumbent species from earlier stages to compete on a more equal footing with inherently more powerful kinds of living objects. This is the role of environmental change in the case of mammalian evolution. Indeed, it suggests that the question should be turned around. If mammals were not inherently superior, then how did they manage to displace dinosaurs when a catastrophic change did finally occur?

The mammalian nervous system evolved during the age of dinosaurs, and the more profound question is how mammals could evolve at all in competition with the incumbent dinosaurs. The answer seems to be that mammals occupied a more demanding ecological niche, where dinosaurs could not compete. And what made that possible was an animal system of representation with spatial imagination.

The first mammals were small, rodent-like animals that apparently foraged (for insects) at night, when dinosaurs could not see them or, perhaps, were immobilized by the cold. Sight was not their major telesensory modality, if we judge by the relative smallness of their eyes. Instead, they had long snouts and external ears, which suggests they had highly developed olfaction and hearing, both of which can be used just as well in the dark. Since all the telesensory modalities contribute in the same way to spatial memory in the subjective animal system of representation,lxxxiv mammals could get around in the dark at least as well as reptiles do with light using only touch, hearing, and olfaction. Touch (including whiskers) would enable them to detect nearby objects, and using their map of the territory, they could get about well enough by keeping track of how far they move in each direction. Their spatial imagination would give them an experience of moving among salient objects in their territory much like the "virtual reality" generated by computers. Hearing (and olfaction) would tell them about objects at a distance, both their location and kind. And olfaction would enable them to recognize particular objects, confirming locations in their map. Thus, mammals could get around in their territory just as well when they could not see.

The subjective animal system of representation also explains parental behavior, including nursing, by which mammals are named. We have seen how the structural cause for various kinds of behavior, that is, the behavior schemata for setting up and using both local images and maps of the territory, are acquired from experience with the structure of space in moving around among objects in 3-D space, rather than from the biological behavior guidance system. Thus, mammalian young are simply not able to acquire energy in the ecological niches they inherit from their parents until they have matured enough to construct local images and link them together in their own maps of the relations of objects in space, that is, as a World Image. Just as birds must care for their offspring before they can fly and acquire energy for themselves, so mammals must care for their offspring until experience in locomotion enables them to develop a spatial imagination. Thus, mammillary glands (in monotremes) and live birth (in marsupials) are probably just an elaboration of the nurturing behavior required by the subjective animal system of representation (as indicated by the early evolution of the neocortex).

One hundred fifty million years is surely long enough to make the subjective animal system as effective as possible in representing the world as a world of objects in space, and so, when the impact of an asteroid caused clouds that changed the climate, destroying rain forests and rich vegetation over much of Earth, mammals were better able to adapt to the new conditions than dinosaurs.

As telesensory animals, dinosaurs had to rely on more or less complex fixed action patterns that enabled them to construct maps, acquire energy, and attain other goals in the previous, lush environment, and reproductive causation was the only way to adapt those complex instincts to radically new conditions.

Mammals, however, had the advantage of spatial imagination; when a desire was strong, they had the capacity to predict what would happen if they moved their bodies in space before they acted, so that "hypotheses die[d] in their stead." And with a behavior generator that operates on a body image to send separate motor commands to all parts of the body, mammals were able to generate new kinds of behavior by putting local motor commands together in new ways and, thus, could learn new kinds of behavior by trial and error within a single lifetime.

Hence, mammals had a distinct advantage when the environmental catastrophe put them on a more equal footing with dinosaurs. Dinosaurs were, of course, already much larger animals, and so it is not surprising that it took many generations before the mammalian population increase and the adaptation of their bodies to the new ecological niches deprived dinosaurs of their sources of energy.

Dinosaurs may have continued to exist for thousands of years after the impact of the asteroid, but that would not be long enough for them to evolve the new instincts needed to exclude mammals from their high energy ecological niches. Or to put it the other way, if there had been no mammals, dinosaurs would not have had to compete for energy, and they would probably have adapted to the new environment in the end.

Therefore, although the “radiation” of mammals was occasioned by the extinction of dinosaurs some 65 million years ago, the basic cause was not that dinosaurs were selectively wiped out by an asteroid, leaving mammals to inherit the earth. The asteroid merely changed all the sources of usable energy tapped by animals of both kinds so radically that mammals were able to replace dinosaurs in the new ecological niches because of the inherent superiority of the mammalian brain, with a neocortex, in which a spatial imagination made them better able to acquire usable energy.

It may still seem that the evolution of mammals is not inevitable, because evolution would not proceed through the whole series of possible stages if it were not for such catastrophic events shaking things up enough to make subsequent stages of inherently more powerful primary structures inevitable.

However, it is not an accident that radical changes occur in all the ecological niches at once. It is inevitable on planets like ours. For example, if asteroid bombardment is a result of perturbations in an Oort cloud of debris farther out from the star than where planets can form, as has been suggested, it would probably happen on any planet where life evolves at all. And there are other sources of asteroids. Thus, catastrophic events are normal on planets that orbit stars, and the dependence of evolution on them would not make the stages any less inevitable.

Furthermore, to assume that the overall course of evolution depends on occasional catastrophes is not to suppose that natural selection is caused, after all, by externally originating changes in the environment. What makes it seem that evolution is merely tracking externally caused changes in the environment is thinking of evolution as if only a single species were involved. But when evolution is explained by its ontological causes, we see that many species evolve during each stage of evolution, and from that broader perspective, we can see that the main effect of catastrophic changes in the overall course of evolution is to shake things up so that inherently more powerful organisms are not stymied by the accumulation of accidents. It makes evolutionary stages inevitable. Catastrophes cause mass extinction of species, and the “adaptations” that do take place are the increasing power by which the gradual evolution of inherently superior organisms taps usable energy in all parts of the environment, such as the radiation of mammals after the extinction of the dinosaurs.

The mammals’ higher level of neurological organization does, therefore, account for their gradual evolution, both before and after the catastrophe with which the Age of Mammals began some 65 million years ago. They could occupy more demanding ecological niches alongside dinosaurs before the catastrophic change, and then, once they could compete on a more equal footing, there was a bush-like radiations of mammals. After overcoming the dinosaur's advantage as incumbents in ecological niches, reproductive causation would adapt mammals to acquire free energy from all possible sources in all possible habitats, from jungles and forests to meadows and deserts, and from oceans and rivers to caves and polar ice caps. In short, from our ontological foundation, we can predict not only the revolutionary change with which the age of mammals began, but also the radiation of mammals. It eventually occurs on any planet where life evolves at all.

There is, however, a puzzle. If mammals are inherently more powerful, why didn’t they also displace the birds? Mammals can evolve the capacity to fly. Bats are proof of that. But bird continue to occupy almost all the other high-energy ecological niches open to flying animals.

Are birds incumbents in ecological niches that require a more severe environmental catastrophe before they can be displaced?

Or do ecological niches that depend on flying require only a one-dimensional visual memory for chains of stimulus-response connections that are imbedded in instinctive routines? Since bats fly at night and in caves, where birds usually cannot fly, are they merely taking advantage of their subjective animal system of representation to occupy an ecological niche that is not open to birds? That is, does a vision-based memory without spatial imagination make telesensory animals so powerful in ecological niches that require locomotion by flying that animals with a multi-modal memory and spatial imagination have no advantage — at least, none great enough to compensate for the greater costs of developing a nervous system with a higher level of part-whole complexity?

The unity of consciousness.In Properties, the nature of consciousness, that is, the existence of phenomenal properties, was explained by showing that material substances must have an intrinsic aspect to their essential natures. Spatiomaterialism implies that elementary bits of matter have intrinsic natures. That is enough to explain simple sensory qualia. But that is not a full explanation of the nature of consciousness, because it does not show that intrinsic natures can explain the kinds of phenomenal properties we have (as we noted when explaining the nature of the necessary connection that solves the contemporary naturalists problem of mind in Properties: Ontological explanation of the necessary connection between physical and phenomenal properties).

What reflection (or introspection) reveals are complex phenomenal properties with qualia of many different kinds all appearing to the subject at once. But spatiomaterialism entails a kind of panpsychism, in which only the most elementary bits of matter must have intrinsic natures. Since the intrinsic natures of elemental bits of matter are presumably only proto-phenomenal properties, it remains to explain what Nagel calls the “unity of consciousness.”

But how can the intrinsic natures of the most elementary physical objects account for complex phenomenal properties? It cannot come from how simpler physical objects are related spatially as parts of more complex physical objects, for there is no reason to believe that a composite physical object, like the brain, will have an intrinsic nature as a whole. The parts of the brain are outside one another in space, and the unity of the whole brain depends on the extrinsic natures of the parts, since what holds the parts together and enables them to interact are the forces that they exert on one another. Thus, it may seem that spatiomaterialism cannot explain why the subject as a whole has phenomenal properties in which qualia are combined in such rich appearances as those that occur in perception.

The nature of complex phenomenal properties. There is one way that spatiomaterialism can explain phenomenal properties (and only one way, as far as I can see). In order to see how it works, we must take into account both the basic nature of matter and the structure of the mammalian brain.

The nature of matter. Spatiomaterialism takes “matter” to refer to all the forms of mass and energy whose quantities are counted in the principle of the conservation of mass and energy, including all the kinds of particular entities to which the basic laws of physics refer. Quantum field theory distinguishes two different kinds of basic particles, fermions and bosons. They have opposite natures in a relevant way.

Fermions and bosons have opposite relationships to other particles of the same kind.

Particles such as electrons, quarks, and nucleons are fermions. With “½ spin” (or a multiple of it), they exclude other objects of the same kind from occupying the same location or quantum state (except for one other particle with the opposite orientation of spin).

Photons, with a spin of 1, are the prime example of bosons (though bosons can also have spins of 0 or 2). Bosons do not exclude one another from occupying the same quantum states, and so there is no limit to the number of bosons of any kind that can have the same location.

Fermions and bosons have opposite relationships to space.

Fermions (with mass) are most like ordinary physical objects, for they are point-like particles (or spatial complexes of them) which are able to be at rest is space.

Photons are interacting electric and magnetic forces, and by contrast to fermions, they seem to be spread out in space, for even though they exist only as whole (quantum) units, they move through space at the velocity of light. (A boson-like nature is also found in the electric forces by which fermions interact with one another, but as we have seen this form of matter is spread out as a field and the way it coincides with space means that its quantity is included in the total rest masses of the objects exerting the forces.)

According to spatiomaterialism, all the simplest bits of matter mentioned by physics must have intrinsic natures. But since bits of matter can occupy more than just a single point in space, there is no reason to deny that their intrinsic natures can have spatial structures. That suggests that, since photons seem to be units spread out in space, they could have intrinsic natures with complex spatial structures, even if fermions do not.

The basic nature of photons opens up, therefore, the possibility of an explanation of complex phenomenal properties by intrinsic natures. But we are still far from seeing how it works.

To be sure, the photon-like nature of the electromagnetic forces binding electrons to nuclei in atoms and atoms to one another in molecules may also give each of them an intrinsic nature as a composite whole. But their intrinsic natures extend only as far as the objects they bind, and since that is not far enough to include whole brains, their intrinsic natures can hardly account for phenomenal properties. To see how it is possible, we must consider the structure of the brain.

The structure of the mammalian brain. The basic structure of the mammalian forebrain involves a massive projection of neurons from the thalamus to all parts of the neocortex (and back), and as we have seen, the brain’s main functions are all served by its massively parallel information processing. Different nuclei in the thalamus project to distinct regions of neocortex, and there are three complete circuits from the neocortex through other structures back to the thalamus and neocortex. Information is being processed within those circuits in two-dimensional arrays of neurons (as shown by association fibers that connect them topographically). Many such 2-D arrays in the posterior neocortex are clearly processing sensory information about the same objects in space at the same time, and many other 2-D arrays in the anterior neocortex are processing both sensory input from and motor output to the body at the same time. Finally, a 40-75 hertz pattern of firing set up by the thalamus apparently synchronizes activity in all areas of the neocortex, integrating the three complete circuits.

Crick and Koch (1990) defend the hypothesis that the 40-75 hertz synchronization of the firing of thalamic neurons to the neocortex is the foundation of consciousness. But they do not explain how it gives rise to phenomenal properties. Given the spatiomaterialist explanation of intrinsic natures, however, phenomenal properties could be explained as the intrinsic natures of the electromagnetic waves set up by the synchronized firing of neurons throughout the thalamic projection to the neocortex.

Electromagnetic waves are, of course, photons, one of the basic forms of matter contained by space, and since they are generated by the acceleration of charged particles, they are clearly being generated by brain activity. A neuron carries signals from one place to another by an “action potential” which propagates along its axon as ions of one kind at each successive point rush into the neuron and then ions of another kind flow back out. The acceleration of such ions makes the synchronized firing of thalamic neurons act like an antenna, generating a complex electromagnetic wave.

Since electromagnetic waves, being composed of elemental photons, are a form of matter whose spread-out nature could give their intrinsic nature a spatial structure, there is an elemental bit of matter generated by active brains whose intrinsic nature could have enough spatial structure to account for complex phenomenal properties. It is the electromagnetic energy being given off as a series of complex photons by a human brain that is not asleep.

This is all the more plausible when we consider that the brain, despite making up only a few percent of body weight, accounts for nearly 20% of the body’s total energy consumption.

In order to be sure that the intrinsic nature of the energy being given off by the brain accounts for phenomenal properties, more would have to be known about the complex geometrical structure of the photons generated by the synchronized firing of neurons in the thalamic projection to the neocortex. Indeed, it is likely that much more remains to be discovered about the basic nature of light than physicists suppose. But that is beyond the scope of this argument. But for our purposes, it is enough to see how this ontological explanation of the nature of properties, this ontological explanation of the truth of physics, and this ontological explanation of the structure of the subjective animal system of representation combine to provide an explanation of the kinds of phenomenal properties that beings like us have.

Complex phenomenal properties. To make it plausible that what is relevant is the energy being given off by the thalamic projection to the neocortex, let me suggest how it would explain what Nagel called the “unity of consciousness.”

The unity of consciousness can be seen in perception, for at any moment, many particular qualia from several sensory modalities all appear to be located in and around one’s body in what can only be called phenomenal space. Objects with colored surfaces appear to have locations around the body, and they often make noises that seem to come from their locations. Color and tactile qualia also seem to be located in the body, and as it moves, one can feel objects at certain locations in space outside the body. The spatial coherence of the perceptual appearance is so complete that many philosophers who are otherwise critical realists still assume that the space in which sensory qualia appear to be located is the same space in which the objects (and body) they represent actually exist, that is, the the qualia are somehow projected outside the brain. But since spatial aspects of perception are just as much part of phenomenal properties as the sensory qualia themselves, we must distinguish phenomenal from real space.

There are at least three reasons to believe that complex phenomenal properties like these can be explained by the intrinsic natures of the photons generated by the thalamic projection to the cortex.

First, as the anatomy of the brain suggests, all the information processing of sensory input leading to motor output that is going on in the brain is registered in the firing of neurons in the thalamic projection to the neocortex and, thus, in the electromagnetic waves it generates.

There are three way in which the projection from the thalamus to the neocortex projects back to the thalamus, completing a circuit. All areas of neocortex have association fibers that project to the temporal lobe near the hippocampus and thereby connect (via the fornix) with the anterior nucleus, which projects back to the cingulate gyrus of the neocortex. All areas of the neocortex also project to the corpus striatum and thereby connect through the ventral anterior and ventral lateral thalamic nuclei back to the frontal neocortex. Also located in the temporal lobe is the amygdala which connects by way of the dorsomedian nucleus of the thalamus back to the frontal regions of the neocortex. The first circuit clearly mediates the formation of long term memory; the second generates behavior in relation to objects in space; and the third attaches desires to objects by arousing disposition to behave toward them in certain ways. Thus, the thalamo-cortical projection seems to mediate all the main brain functions.

But since the neocortex is one of the mechanisms involved in all three complete circuits which realize the subsystems of the subjective animal behavior guidance system in mammals, its neurons (including association fibers between 2-D regions of neocortex) may also contribute to the photons whose intrinsic nature constitutes phenomenal properties.

Second, it seems possible to explain the spatial coherence of complex phenomenal properties, at least, in principle. It is likely that simple sensory qualia are parts of the electromagnetic wave generated by thalamic neurons projecting sensory input to primary sensory areas of neocortex, for when they fire, they fire at an unusually high rate. The appearance of green at a certain location in the visual field, for example, is presumably due to the rapid firing of certain neurons in the 2-D array projecting from the lateral geniculate body of the thalamus to the visual (striate) cortex.

Given how colors vary with different combinations of the intensity of opponent colors (red-green, blue-yellow, and black-white), the relevant wave patterns presumably depend on the combination of neurons projecting to each region of the visual cortex that originate at different lamina of the lateral geniculate body and fire at different synchronized rates.

Since all the 2-D arrays processing visual input in the neocortex are connected to one another topographically by association fibers, the neurons in each that represent the same parts of an object’s visual appearance are presumably synchronized throughout the neocortex. That ties higher-level processing to the corresponding neurons responsible for sensory qualia and integrates all their effects on the electromagnetic wave, so that its spatial structure could contain all the information the brain uses for guiding behavior.

The same is true of the various 2-D arrays representing the body, and given how those body representations are connected with visual and other sensory 2-D arrays, it is not implausible to suppose that the result is a series of photons generated by the entire thalamo-cortical projection whose intrinsic natures are spatially coherent. That could be why sensory qualia seem to have locations in phenomenal space.

The fainter qualia of all sensory modalities that occur in memory and imagination could likewise be explained as due to centrally-generated firings of neurons that otherwise occur only in later stages of the process of sensory analysis.

Finally, locating the phenomenal property in nature as the intrinsic nature of the electromagnetic wave generated by the thalamic projection to the neocortex would explain the phenomenon of blindsight. When the projection from the thalamus to the visual cortex is damaged and subjects claim not to have any visual experience, they are still able to answer questions about the locations and shapes of objects and to take them into account in their behavior. The lack of visual qualia is what would be expected on this theory, since what is missing is the relevant thalamo-cortical projection. And the residual visual discrimination could be explained by the visual processing still going on outside the forebrain in the superior colliculus (the midbrain nucleus that was responsible for using visual input to guide behavior in reptiles) and its limited projection to a region of the thalamus (the pulvinar) that projects to secondary areas of the visual neocortex.

Ontological philosophy offers, therefore, a plausible explanation of the unity of consciousness. The physical properties of the photons generated by the brain suggest that they are a form of matter whose intrinsic natures could be the complex phenomenal properties we have. What makes it possible to solve the explanatory problem that Nagel finds in panpsychism is the recognition that space is a substance. Coinciding with space explains not only why bits of matter have spatial relations to one another, but also how they can coincide with whole regions of space. Thus, it shows how their intrinsic natures could have complex spatial structures, and that makes it possible to see how photons can have a spatial structure that depends on activity throughout the brain, accounting for the complex structure of the phenomenal properties that we are calling "consciousness."

An attractive feature of this explanation is that it suggests a research project. Complex phenomenal properties might be explained in detail by working out precisely the geometry of the electromagnetic waves generated by ions being accelerated in and out of cylindrical axons of certain neurons in each of many 2-D arrays of the massive, basically parallel projection from the thalamus to the neocortex as they fire simultaneously 40-75 time each second.

Furthermore, if the synchronization of firing cycles throughout the thalamus is required for the coherence of the complex phenomenal property, it can settle a question about the unity of consciousness in split-brain patients. In split-brain patients, the massive corpus callosum which connects the two hemispheres of the brain is cut (usually in order to prevent epileptic seizures). Whether they have one or two minds, that is, one or two unified appearances made of sensory qualia in phenomena space, would depend on whether their thalamic nuclei are still synchronizing the firings of neurons in both hemispheres. That is something that could be determined empirically.

Implications. Even without carrying out those research projects, however, this explanation of phenomenal properties, if true, has consequences that are relevant to the positions mentioned in the discussion of consciousness in Properties.

Epiphenomenalism. Thomas Huxley likened epiphenomenal properties to the whistle or steam giving off by a steam locomotive, because they have no causal role in propelling the train. If we take “epiphenomenal” to mean being an effect of physical properties without having any effects in turn on physical properties, the spatiomaterialist explanation implies that phenomenal properties are epiphenomenal in two different ways.

First, as we have seen, phenomenal properties are epiphenomenal relative to physical properties as such, because they are kinds of intrinsic natures that are caused to exist as a result of extrinsic natures of the bits of matter involved. That is, the spatial structures of the photons that account for the complexity of the relevant phenomenal properties are also aspects of the extrinsic natures of those bits of matter, because those spatial structures can in principle, be explained by physics.

Second, since the relevant bits of matter are the electromagnetic waves, they are just a form of energy being dissipated by the brain as a by-product of its activity, and so those bits of matter themselves are epiphenomenal relative to the physical properties of the brain itself. Those photons are effects of the brain’s activity that do not, in turn, affect its states. (What happens in the brain is caused by the synapses made by the neurons that fire, not by the photons generated by their action potentials.)

Thus, phenomenal properties depend on two “causal” connections, the efficient cause by which the brain activity causes electromagnetic waves, and the ontological cause linking the extrinsic natures of the electromagnetic waves to their intrinsic natures.

Robot consciousness.Given that phenomenal properties are the intrinsic natures of the brains’ electromagnetic waves, it is not very likely that robots whose behavior is guided by computers made of silicon chips will be conscious in the way we are. Though they will also generate electromagnetic waves and will, therefore, have some intrinsic nature or other, it is unlikely that their phenomenal properties will be anything like our own.

Their information processing is basically serial, rather than parallel, and since silicon chips have, in any case, a completely different geometry from brains, the rising and falling electric and magnetic forces in the “wires” of silicon chips will generate photons with a completely different geometry in space and time.

Nor can such robots experience sensory qualia as located in space, if what is responsible for the unity of consciousness is, as suggested above, the synchronized processing of representations of the same objects in different, interconnected 2-D arrays of neurons projecting to the neocortex.

Ontological philosophy also implies, therefore, that Chalmers (1996, Chapter 7) was mistaken to believe that phenomenal properties are caused by functional, rather than by physical properties. His argument was the implausibility of qualia slowly “fading” out as parts of the brain were replaced by functionally equivalent silicon circuits, and the implausibility of color qualia “dancing” from one kind to another (or to none at all) as the processing of part of the visual array was switched between brain mechanisms and silicon chips. Implausible though it may seem to Chalmers, that is what must happen, if phenomenal properties are the intrinsic natures of electromagnetic waves generated by the processing. But at this point, his fading qualia and dancing qualia arguments show, not the implausibility of phenomenal properties being caused by physical properties, but rather the perils of giving up the empirical method (as in empirical ontology) in favor of philosophical arguments from plausibility (where functions and other properties seem more basic than substances).

Knowledge of phenomenal properties.Ontological philosophy makes consciousness a part of natural science without abandoning the empirical method in favor of the traditional epistemological approach to philosophy. But since it implies that phenomenal properties are epiphenomenal, they have no effects on what happens in the natural world, and thus it may seem that phenomenal properties cannot be known even privately. How can subjects know about their phenomenal properties, if those properties are never causes of what they say about them?

That phenomenological properties do cause beliefs about them is apparently what Descartes assumed in arguing, "I think, therefore I am." In order for thinking to show the subject that he exists, the subject must know that he is thinking when he is thinking, and Descartes seems to take it for granted that the subject knows that he is thinking because the appearance of the ideas in the mind makes the subject aware of what is happening in his mind. (That is the "illusion involved in reflection" that Descartes still does not see through after he sees through the "illusion involved in perception" and becomes a critical realist.)

Nor would this problem arise if phenomenal properties played the kind of causal role mediating between sensory input and behavioral output that Searle (1992, 1995, and 1997) ascribes to pain, that is, being an effect of, say, a pinch, which in turn causes one to say “Ouch!” In that case, phenomenal properties would be effects of sensory input, and they would be the causes of reports about them. But causal emergentism of that sort is incompatible with spatiomaterialism.

Given this explanation of the mammalian brain and consciousness, however, it is not necessary for phenomenal properties to be efficient causes of behavior in order for them to be private objects of knowledge.

First, to see how we can know that we have phenomenal properties, we need only recognize that such knowledge comes from (and arose historically in modern philosophy from) accepting critical realism, that is, distinguishing phenomenal properties from physical properties. It is like something to be a human being, as we have seen, because the functioning brain involves a bit of matter whose intrinsic nature registers the activity of the entire brain. We assume, as naive realists, that the world as it appears to us in perception is the real world, with qualia located in objects that are assumed to exist independently of us in space. But when we recognize that perception is a physical process in which the objects stimulate our sensory organs, thereby giving rise to brain states representing them, we can come to see that our sensory qualia are parts of us, as the subject who is perceiving, not parts of the independently existing objects. And if we follow this argument to its conclusion, we also come to recognize that the space in which sensory qualia seem to be located is merely phenomenal and, thus, distinct from the space in which the physical objects actually exist. Critical realism about perception makes it clear that objects with physical properties in real space exist somehow “beyond” the complex phenomenal properties we have, so that we discover that we have phenomenal properties by recognizing that physical properties do not appear to us at all, except indirectly through phenomenal properties.

These spatial configurations of sensory qualia are not the only complex phenomenal properties we have, but they are an important variety, and the failure to give up naive realism about space in favor of critical realism about space is the source of much confusion about the nature of consciousness.

Thus, second, there is no problem explaining how it is possible for subjects to pick out particular qualia included in the structures of their phenomenal properties. The phenomenal properties involved in perception are configurations of sensory qualia in phenomenal space, and particular qualia can be picked out in the same way as the objects in real space that they represent, for once we recognize the difference between physical and phenomenal properties, it is one and the same brain capacity being understood in two different ways. We can take our reference to the green apple on the table to be a reference either to the physical object in real space or to a part of the appearance that the world has to us as we perceive the world.

Finally, there is no problem explaining how we know about the kinds of particular sensory qualia that are picked out that way, for once again, it is just to make the same discrimination that we make in describing the properties of physical objects in real space together with the recognition that there is a difference between physical and phenomenal properties. When I call the cup green, I am ordinarily understood as referring to a physical property of the cup (its disposition to cause a certain kind of experience in us). But when I distinguish the phenomenal property from the physical property, I can also identify the kind of qualia representing the physical property. And there is a kind of incorrigibility to the belief about the kind of particular sensory qualia that does not hold for the physical property, for what is meant by the kind of sensory qualia is how it appears to the subject and that is something that is known ostensively in the phenomenal property.

Ontological philosophy, therefore, makes a natural science of consciousness possible. Though we know about our own phenomenal properties in a unique and private way, we can know that others have them. If other brains generate the same kinds of electromagnetic waves as ours, we can know from what experience is like for us, what it is like for them.

But traditional epistemological philosophy will not survive this change, for it makes even the starting point of modern philosophers, like Descartes, part of the essential nature of a world that is explained ontologically. That is, what will make a natural science of consciousness possible is that there will no longer be any difference between empirical science and philosophy when philosophy takes empirical ontology as its foundation (and science recognizes ontology as a more basic branch than physics). But this is to get ahead of ourselves, for that is how ontological philosophy completes the tenth stage of evolution.

7 Manipulative stage.Having traced the evolution of the animal system of representation from somatosensory through subjective animals with spatial imagination, the manipulative animal system of representation can be predicted, in principle, by the function of structural imagination. Just as spatial imagination gave the mammal an intuitive understanding of spatial causation, structural imagination gives primates an intuitive understanding of structural causation. That is, subjective animals were more powerful than telesensory animals because they could understand how the structure of space imposes regularities on the object’s change of location, and in a similar way, manipulative animals are more powerful than subjective animals because they can understand how the geometrical structures of material objects in space imposes regularities on their interactions. Though there must be some new kind of behavior for it to guide, structural imagination makes it possible to guide such behavior in using structural causes to control relevant conditions. It would be such a basic addition to the power of animal behavior to act on other objects in space that it could begin a stage

In order to predict a stage of evolution during which manipulative animals change in the direction of maximum power in using structural causes, however, it must be possible for subjective animals to try out a random variation that gives animals structural imagination. The functional description of the structures required for structural imagination shows why such a “manipulative animal system of representation” would require a higher level of neurological organization than subjective animals. Thus, only its possibility remains to be shown, in order to infer its inevitability as a necessary truth of ontological philosophy. But the higher level of neurological complexity required for structural imagination does not require such a radical change in brain structure that it is problematic. Moreover, what it does require explains all the ways that actual primate brains are different from mammalian brains.

After giving a functional description of the manipulative animal system of representation, I will describe the structures in the primate brain that realize it and, finally, confirm that it causes a stage of evolution by considering the empirical evidence for a radiation of higher primates.

The function of the manipulative level of neurological organization.The reason that a less radical random variation is needed to try out the manipulative level of neurological organization is that it happens in animals that already have imagination. It is just a higher level of part-whole complexity in the faculty of imagination.

Subjective animals have a faculty of spatial imagination that enables them to understand the structure of space. As we have seen, it comes from a memory that can link local images in sequences as a map of the territory and a behavior generator that generates covert locomotion that can call them up. This gives them subjective animals capacity to anticipate the consequences of locomotion, and motion generally, on the relations of objects in space. It is a conception of space, for it gives the subjective animal an understanding of spatial causation. They can perceive objects as having locations in space. It even enables them to see their own bodies as objects alongside other objects in space, and so the world in which subjective animals act is seen as singular and whole.

Besides the effects of motion on spatial relations, however, there is another spatial (and spatio-temporal) aspect of the world that is nearly as basic, which subjective animals cannot understand. That is structural causation, or the effects of geometrical structures on the interactions of objects that have them. Though mammals can guide locomotion in relation to large geometrical structures in their territory, they merely inhabit such structures and do not see them as the structures of material objects. Mammals have no need to understand structural causation, for they lack the ability to generate animal behavior of a kind that would use structural causes to control relevant conditions, that is, the capacity to manipulate material objects.

Structural imagination. What would make mammals more powerful, therefore, is an ability to manipulate material objects that is guided by an understanding of the consequences of manipulating them on how their geometrical structures appear, how the objects interact, and how their structures change. Understanding requires a faculty of imagination, but since mammals already have one form of imagination, the addition of another kind of behavior and another way recording images in memory is all that is required for what I will call “structural imagination.” It would enable manipulative mammals, for example, to see that round pegs won’t fit in square holes and that cups have to be oriented in a certain direction in order to contain water. More generally, it would enable them to see, in the geometrical structures of material objects, the structural global regularities they would cause, and with the capacity to manipulate objects, they would be able to use their geometrical structures as machines, or tools, in attaining their goals.

A faculty of imagination enables the animal subject to see the actual against the background of what is possible (where “the possible” is basically various sets of sequences of images over time representing the kinds of events that can occur). In the case of manipulative animals, that is to see the actual geometrical structures of objects in the local scene against the background of what is possible by manipulating them.

If its mechanisms paralleled spatial imagination in subjective animals, what is possible by manipulation could be presented to the animal subject (via the projection of the local image to the caudate nucleus) as sequences of images along with perception (or the images derived from current sensory input).

Using the same basic memory system for recording memory groups in sequences (the cingulate gyrus), the detailed structure of the brain mechanisms for generating such sequences of images could be learned by experience. We have seen how the faculty of imagination can contain a form of reproductive causation in which behavior schemata evolve by reinforcement selection. The detailed brain mechanisms for structural imagination can be internalized from the world itself, because that is where structural causes actually generate global regularities, and those regularities are evident in now sensory input depends on manipulative behavior.

Since covert behavior would call up images from memory, thought about geometrical structures would involve appearances to the animal. Given our ontological explanation of the nature of consciousness, those appearances would be the kinds of ideas of imagination and memory to which the modern philosophers were referring. In manipulative animals, therefore, the representation of geometrical structures would be explicit.

None of these consequences of behavior is even conceivable by subjective animals, because the geometrical structures of objects are merely implicit in their local images (the combined telesensory images of objects located in the current scene). When the subjective animal focuses on an object, its location in space is represented explicitly, because its telesensory effects are registered along with other telesensory images as parts of a local image (according to input from the bodily condition), and that image contains information that can guide locomotion in relation to objects located in the local scene. The local image is the perceptual appearance of the local scene to the subjective animal, and it is conscious perception, because it has a phenomenal appearance.

But even though the object’s geometrical structure may correspond to a structure in the local image, or telesensory image in the complex idea representing the local scene, its geometrical structure is not represented as a geometrical structure, because the object’s geometrical structure is not used to guide manipulation in relation to it, but, at most, to identify the object or to recognize its kind. The geometrical structure may enable the mammal to see that it is an object of some kind that is located in space. But the mammal does not see it as having a kind of shape that can be changed or used in some way. It is as if subjective animals moved around in a world of shapeless (yet identifiable) objects with locations in space, and with the evolution of structural imagination, those objects acquired shapes that could be used as means in attaining animal goals.

The goals pursued by manipulative animals would be somewhat different from goals of subjective animals. Goals would be selected in the same way, by attaching desires to objects, where desires are basically dispositions to behave in a certain way toward an object. But manipulative animals would have new ways of behaving. For example, apes can pick gnats from one another’s fur and build beds, while cats can only lick themselves (or their kittens) curl up somewhere comfortable. New desires would evolve, because with structural imagination, manipulative animals would be controlling relevant conditions that were out of reach for subjective animals.

In short, whereas subjective animals have a conception of space, manipulative animals would have a conception of geometrical structures in space. And whereas subjective animals perceive objects as being located in space, manipulative animals would perceive objects in space as having geometrical structures.

The various functions and sub-functions of the manipulative animal system of representation are depicted in the accompanying diagram of the manipulative animal behavior guidance system. Though neural mechanisms serving the function of selecting the kind of behavior are essential to the animal behavior guidance system, only the mechanisms serving the sensory input and behavioral output sub-functions are involved in the animal system of representation (the parts with the gray background). The diagram of the subjective animal behavior guidance system is also included here, because the contrast brings out what kind of higher level of neurological organization is required by the manipulative animal system of representation.

The functions of the systems making up the subjective animal behavior guidance system will be assumed, and only the additional systems required to supplement spatial imagination with the capacity to understand structural causation will be described. (The new neural mechanisms required to serve these new functions are identified below in the section, which uses the structure of the primate brain to show the possibility of the manipulative level of neurological organization.)

The brown squares represent the sensory input and behavioral output systems, and the black lines represent their basic connections to one another and the body (including telesensory input, somatosensory input, input about the current bodily condition, their combination as the perception of the object, and how that is responsible for overt behavior when some kind of behavior is selected). They are the basic structure of the telesensory animal system of representation. They are all depicted in the subjective animal behavior guidance system, but for simplicity in the manipulative animal behavior guidance system, the internal connections between the sensory input and behavioral output system (perception and input about the current bodily condition) are suppressed.

The red lines and red circles in the sensory input system and behavioral output system are what is added to the brain to give the subjective animal spatial imagination. Their complete circuits indicate the higher level of neurological organization in subjective animals (though as we have seen, the behavior generator is actually another complete circuit in itself, which is not represented in these diagrams).

The lavender lines and circles in the local image and body image of the subjective animal system of representation only suggest the kind of higher level of neurological organization required to give manipulative animals structural imagination, because there are actually four sets of new sub-systems, one for each hand and one for the object each hand can manipulate (which are not all represented for the sake of simplicity). The lavender lines represent the causal connections between the new sub-systems by which they function as the manipulative animal’s structural imagination.

Behavioral output system. Overt behavior for the whole body is caused by motor commands from the body image, as in other subjective animals. Those commands are issued by the behavior generator for the whole body using one of its behavior schemata. The behavior of hands in manipulative animals is caused in the same way, but within the context of the body. Hence, the behavioral output system for the hands is depicted as being located within the body image (though it is just a distinct part of the complete circuit through the frontal neocortex, corpus striatum and ventral thalamus for the whole body).

Overt manipulation is caused by motor output to muscles in each of the hands (and limbs) from each of the hand images, and the motor commands are generated by behavior generators for the hands using their behavioral schemata for manipulation. But the entire behavioral output system for the hands is depicted as being part of the body image, because, functionally, manipulation is a kind of behavior that is generated in just certain parts of the body.

Both are behavioral output systems, each with its own behavioral schemata, and thus, they are basically independent structural causes of behavior. In other words, there is a part-whole relationship between the behavioral output systems for the hands and for the body that corresponds to the part-whole relationship between the hands and body themselves. The behavior of the body as a whole is the larger context in which manipulative behavior is generated, as if manipulative behavior were simply appended to the behavior of the whole body. But they are distinct circuits, which can operate independently (and as we shall see in the linguistic brain, body and hands can both be operated by higher level linguistic schemata as if they were on a par).

The behavioral output system for the hand is labeled “hand image” because motor output to the hands is organized somatotopically as representations of the hands. The hand images are just parts of the body image, for the body image is organized somatotopically and includes the hands. And just as the body image receives somatosensory input from all parts of the body, the hand images receive somatosensory input from all parts of the hands.

But since tactile input, which is a kind of somatosensory input to the hands, is used to perceive the geometrical structures (and locations) of objects in the local scene, the diagram also represents tactile images as sensory input to the object image. (Thus, it might be called “exteroception,” to distinguish it from proprioception and interoception.)

The behavior generator for each hand contains schemata for all the various ways that that hand can manipulate objects, and depending on input from the goal selection system, the behavior generator uses one of its manipulative schemata together with the perception of the object in the local scene (that is, the object image, or the input from the sensory input system) to generate precise motor commands that are adapted to the geometrical structure of the object. Thus, hand-eye coordination is possible.

The behavior generator itself for both the body and the hands is also actually a complete circuit (through the ventral anterior nucleus of the thalamus, the frontal neocortex, and the corpus striatum, though it is not represented in the functional diagram). The behavioral schemata are structures recorded in the frontal neocortex, but it is a different region of the neocortex from the body image and hand images from which motor commands are issued (that is, the motor area).

The behavior generator can, with the appropriate behavioral schemata, generate a wide variety of manipulations. Since motor output sends commands separately to each part of each hand, they can be combined in many different ways. And manipulative schemata may involve many steps, because the behavior generator for each hand has feedback from the motor output to its hands by which the completion of one motor command can trigger the next in a sequence, generating temporally complex patterns of manipulation.

Sensory input system. As in subjective animals, the manipulative animal’s local image is constructed from the telesensory input of objects in the local scene, using input from the bodily condition to register telesensory images according to the stance of the body, head, eyes and ears that controls them in the local scene. But there is a new level of part-whole complexity in the local image, because telesensory (and tactile) images from objects are also registered as parts of an “object image” according to input about the bodily condition indicating the current motor commands and sensory input to the hands.

What makes an object image possible is that the local image also contains a new memory system by which telesensory and tactile images of objects can be recorded in sequences according to overtly generated manipulation and by which those images can be recalled in sequences according to covertly generated manipulation. The entire sensory input system for objects, both the object image and its memory, are contained within the local image, because, functionally, the object image is framed by the local image. It must be in order to represent effects of the geometrical structures of objects, because they occur within the local scene.

The object image functions more like the subjective animal’s entire map of local images than like their local image, because structural imagination gives the object image a meaning that resembles the meaning that spatial imagination gives to the local image.

As we have seen, the subjective animal’s capacity to see the telesensory images combined in the local image as spatial relations between objects that can change as they move comes from spatial imagination and its capacity to call up sequences of local images by covert locomotion. It gives the local image an “outside” relationship to other local images, and that makes the spatial relations among objects represented within the local image meaningful in a new way, because their locations can be seen as places where the animal might go and turn, calling up a new local image.

With the evolution of structural imagination, the local image has a comparable relationship to object images, except that object images are “inside” the local image, rather than “outside.” The object image is made up of sequences of telesensory and tactile images, representing the consequences of manipulation. But as they change, the local image remains the same (except for those changes). When a rock is rotated, for example, one side after another comes into view, but the background remains the same. However, the changes in the rock do not just happen, but are caused to happen by turning it in a certain way, and thus, the telesensory and tactile images that are part of an object image are meaningful. The geometrical structures that appear to the manipulative animal in those images have a meaning that comes from understanding geometrical structures in terms of the consequences of manipulating them, in much the same way as the meaning of the spatial relations among objects in the local scene comes from understanding them in terms of the consequences of locomotion and turning in relation to the objects. The manipulative animal can see the geometrical structure of the object as something that would change in a certain way, if it were rotated or twisted appropriately, just as the subjective animal can see the spatial relations among objects in the local scene as some that would change in a certain way, if some object were to move appropriately.

In other words, the object image and the territorial map have opposite relations to the local image and the telesensory and tactile images of which it is composed. The object image involves sequences of telesensory and tactile images within the local image, whereas the territorial map involves sequences of local images themselves, that is, outside the given local image.

In both cases, sequences of images are recorded in memory in conjunction with the kind of behavior being generated overtly at the time, and so they can be called up in the same order when behavior of the same kind is generated covertly. The difference is that the behavior that is relevant to changes in object images is manipulation, whereas the behavior that is relevant to changes in the local images is locomotion (and turning).

This parallel between spatio-temporal and structural imagination means that memory can function in basically the same way in both cases. In both cases, there must be a system that can record images in sequences. It must be able to record them according to the kind of overt behavior being generated at the time the images are received. And it must be able to recall images from memory according to covert forms of such behavior as labels, so that they appear as imagination to the subject. The same system that serves these functions in spatial imagination can be used for structural imagination, if (1) manipulative animals have a new form of behavior and (2) the images called up from memory can be handled somehow independently of the local image in which they occur.

(1) The foregoing description of the behavior generator for the hands explains how manipulative animals can have a new form of behavior. It comes from having hands as four new parts of the animal body. Thus, in addition to locomotion, turning, and the orientation of the body, head, eyes, etc., the manipulative animal has ways of behaving that depends on the hands and how the arms put the hands in certain locations in the local scene.

There are many different ways of manipulating objects. Objects can be turned, for example, in three independent ways in three dimensional space. The fingers can trace their outlines in different ways. And there are various ways of acting on objects to change their shape, as in folding paper.

Assuming that overt and covert behavior have the same kinds of connections to the memory system (projections to the anterior cingulate gyrus and its projection in turn to the posterior cingulate gyrus), each kind of manipulation could call up a different sequence of sensory images.

(2) However, since the memory system is already being used for spatial imagination, the new memory system must be able to have a different kind effect on the local image than locomotion and turning. In order to serve its function, instead of calling up new local images, it must be able to call up new telesensory (and tactile) images within a given local image. That is what is labeled as the “object image” within the local image of the functional diagram.

Though at any moment, the object may be just one of the telesensory images that are combined as the local image representing the current local scene, the object image is different, because it can be changed by covert manipulation independently of the rest local image, at least in imagination. That is the object image’s connection to the memory system within the local image in the functional diagram.

The world appears differently to animals with structural imagination. Not only do they see themselves as a body located in a local scene along with other object with spatial relations to one another that can be changed by locomotion, but they also see the objects in the local scene as having structures.

As the manipulative animal plays with an object, say turning it, it receives a series of telesensory and tactile images, and sensory images are registered according to what its hands are doing to it. This can record an object image for that particular object in memory. Thereafter, even though only one aspect of the object may be causing sensory input at the moment, the object image can represent other aspects of the object as well, for images of the other sides can be called up from memory. Thus, manipulation involving the backside, for example, can be rehearsed in imagination before it is generated overtly. The manipulative animal perceives the object as having a certain back side. Or objects with moving parts, such as a box with a lid, can be imagined to have configurations that are not seen.

But the capacity to record and recall sensory images according to manipulation is not just a memory for particular objects, any more than the capacity to record and recall local images according to locomotion is just a map of a particular territory. As we have seen, learning to construct and use memory maps gives the subjective animal a general conception of space, by which they can understand any relations in space by imagining the kinds of motion that would be involved in traversing or changing them. Similarly, the manipulative animal acquires the concept of geometrical structure.

The subjective animal’s general understanding comes from the structure of the memory system on which imagination is based, because the same kinds of behavior generated in similar situations have the same kinds of effects. That is what the spatial structure of the world contributes, and thus, as behavioral schemata evolve by reinforcement selection, the connections in the memory system internalize those general relations. Their internalization is the subjective animal’s conception of space.

The memory system in manipulative animals internalizes a further spatial aspect of the world in the same way. The same kinds of manipulation have the same kinds of effect on objects with the same kinds of geometrical structures. Rotating them in any of the three independent planes possible leads to similar sequences of telesensory images, for example, and likewise for bringing the object closer or moving it to the side. The appearance of hollow objects from the outside can be used to infer how they would appear from the inside. Similar shapes also cause similar tactile images when the fingers move relative to the object in certain ways.

Thus, by recording objects with similar geometrical structures together as the same generalized object images, there would be a “map” of the consequences of manipulation that would work for all objects of that kind involving that kind of manipulation. And the different sequences of images involved in manipulating them in different ways could be interconnected like the sequences of local images representing different directions of locomotion from the same scene, because changing the direction of rotation would have effects that parallel changing direction at some point in the territorial map.

The contained form of reproductive causation in which behavioral schemata evolve by reinforcement selection, which has been described in subjective animals, would enable manipulative animals to acquire the ability to manipulate objects in all ways that are physically possible for the kinds of hands they have, as long as they enabled the animal to control some relevant condition and were reinforced by the memory circuit (in alliance with the goal selection system). Thus, they would internalize structural global regularities about change in the world as part of the structure of their structural imagination. And manipulative schemata would tend to evolve in the direction of more abstract representations of the geometrical structures of objects, though there may be a limit to how useful such abstract understanding is in ecological niches where they do not help satisfy desires.

Structural imagination would also enable manipulative animals to learn complicated tasks involving hand-eye coordination, if that were useful in satisfying desires. The motor output is sent to the hands from an image of the hands that is part of the body image, and by sending separate motor commands from different parts of those images of the hands to different parts of the hands, it is possible for the behavior generator to generate very complex bodily movements in relation to objects in the object image. A set of motor commands is sent each moment and it can generate long sequences of such sets of such motor commands.

To be sure, the behavior generator for the hands needs a “schema” for each kind of behavior, but such manipulative schemata can also be learned from experience with the world, that is, by operant conditioning and the evolution of behavior schemata in the behavior generator, just as subjective animals learn complex routes through their territories.

Manipulative animals may even learn a behavioral schemata that enables them to recognize how other manipulative animals are manipulating objects. That is, when they learn to manipulate objects in certain ways, they also learn to recognize when other manipulative animals are manipulating objects in the same way. Manipulative animals with that skill could not only recognize kinds of manipulation in other animals, but could also understand the manipulation in the sense of knowing how to act the same way. Since manipulation can be generated covertly, manipulative animals would be able to call up telesensory images from memory of another body behaving in a certain way, so that the behavior it is rehearsing could be seen from the outside, where it may be easier to imagine how it would fit into the current scene.

However, far from being a mere recording devise for learning complex manipulative tasks or for viewing aspects of objects in imagination, the most general new power is the capacity to think about objects as having geometrical structures. With abstract concepts of geometrical structure, particular objects can be represented in structural imagination by adding whatever details about the particular object may be relevant to a general concept. Cups hold water in the same way, and that general conception of cups becomes a formula for memories of particular cups. And their intuitive understanding of geometrical structure would enable manipulative animals to think about objects in terms of how they would interact with other objects in the local scene because of their geometrical structures, that is, as an understanding of structural causation. Thus, an ape can see branches from trees as something to be assembled as a bed to sleep comfortably, or, as in the case of Kohler’s ape, see how a box and a stick would enable it to knock down a banana which was otherwise out of reach. It is, in other words, the capacity to see objects as tools or machines. That is the sense which objects in space are seen as having geometrical structures.

The goal selection system serves the function in the manipulative animal behavior guidance system as the subjective. It attaches desires to objects. Such desires are actually dispositions to use certain behavioral schemata in relation to the object identified, and thus, not only can manipulative animals have new or refined kinds of desires to attach to objects, but new kinds of problems can be solved in satisfying them. Though it may not be possible to remove an obstacle that is frustrating the satisfaction of a desire by locomotion, it may be possible by manipulation. For example, primates can figure out how to unlatch gates, though dogs cannot.

The possibility of the manipulative level of neurological organization. The functional description of the manipulative animal system of representation shows how a higher level of neurological organization would make animals more powerful in a basic way, by giving them the use of structural causation. Since the manipulative level is functional in a profound way, all that is required to infer its inevitability is sufficient reason to believe that such a neurological structure can be tried out as a random variation on the brains of subjective animals.

The possibility of the higher level of part-whole complexity is not very problematic in this case. Since subjective animals already have the kind of memory that can record and recall images in sequence according to the kind of behavior that causes them, it requires only two kinds of changes, one each in the behavioral output and sensory input systems. One change is the addition of four new subjective level behavioral output systems, one for each hand, installed as parts of the behavior generator for the body as a whole. The other change is some way of handling as many as four object images within the local image of the sensory input system.

These changes are less radical than what was needed to cause earlier stages of chordate evolution, because they do not involve a further centralization of the whole nervous system.

In order to use telesensory input to guide locomotion, the functions of all the local reflexes of the somatosensory chordate's nervous system had to be centralized in the non-mammalian vertebrate brain where the interaction between sensory input and behavioral output could be separated from the goal selection system.

And in the evolution of subjective animals, the three systems of the animal behavior guidance system (behavioral output, sensory input, and goal selection), which were located in the hindbrain, midbrain and forebrain in non-mammals, had to be centralized in the mammalian forebrain, where the behavioral output and sensory input systems could each be composed of several telesensory level brain mechanisms and interconnected so that behavior could be generated both covertly and overtly.

Centralization is not, however, the only way a higher level of part-whole complexity can be introduced in neurological mechanisms. Instead of housing multiple lower-level systems alongside one another as part a whole new structure, it is possible to introduce a higher level of part-whole complexity by multiplying parts within the main systems of an existing animal system of representation. Though this is a less radical way of organizing nervous mechanism on a higher level of part-whole complexity, it is just as much the cause of a new stage in animal evolution, because it is the fountain of a whole new range of powers that can evolve gradually over a long period of time.

Since a relatively minor change of this kind is surely within the range of random variations that can be tried out by the biological behavior guidance system, we could take the possibility of mammals with structural imagination for granted and conclude that manipulative animals are inevitable. But there is further confirmation, because the kind of manipulative mammal we are looking for does exist on earth, and its brain does have just the kinds of structures we expect.

The mammals that most obviously have structural imagination are primates. But they may not be the only manipulative animals. It is possible that elephants also have a kind of structural imagination for guiding the behavior of their trunks.

In the primate brain, at least, the is good evidence of both kinds of changes in the mammalian brain.

In the behavioral output system of primates, there is clear evidence of multiple behavioral output systems within the behavior generator for the body as a whole.

And there are just the kinds of changes in the sensory input system we should expect for accommodating object images within the frame of the local image.

Behavioral output system. Since the evolution of hands for manipulating objects is the clearest evidence of a higher level of neurological organization, let us begin with the behavioral output system.

The body image for issuing overt motor commands to all parts of the body includes the primary and supplementary motor cortex as well as the somatosensory cortex, and as we might expect, the areas devoted to the hands in the primate brain are much larger than in non-primates. They are the hand images for overt behavior in the functional diagram.

There are presumably also larger areas for the hands in the covert body image (that is, in the premotor neocortex and in the anterior geniculate neocortex) for generating covert manipulation in parts of the body as a whole.

The new hand images of the behavioral output system are connected to the behavior generator in the same way as the rest of the body, for the hand images are just part of the body image. That is, manipulation in each hand is generated as a separate part of the circuit from the anterior neocortex through the corpus striatum, the ventral lateral and ventral anterior nuclei of the thalamus, back to the anterior neocortex. Yet these hand behavior generators are just part of the body behavior generator. That is how we expect the higher level of neurological organization to be accomplished from the functional diagram.

In mammals, behavioral schemata are contained in the frontal neocortex, and in primates, there is such a great overall increase in the size of the frontal neocortex that primates are often said to have a new "prefrontal" lobe. (The prefrontal neocortex is just anterior to the frontal eye field, including areas 9 and 10 as well as 45 and 46, and all these areas granular, having all six layers of cortex.) These new areas of neocortex, like the frontal neocortex of non-primates, are available to the behavior generator, because they are parts of its circuit for generating behavior.

They all project to the putamen of the corpus striatum, and because the corpus striatum projects to the ventral anterior nucleus of the thalamus, the circuit is completed by the projection from the ventral anterior nucleus back to the frontal neocortex. This circuit lines up 2-D arrays of neurons in each structure it passes through, and thus, as one cycle of interactions through the circuit follows another, the spatial complexity of the behavioral schema in the frontal neocortex can be translated into a temporal sequence of motor commands. But since the projections to the putamen tend to consolidate different areas of the neocortex that are involved in generating each part of the body, there are distinct circuits within the circuit for the body as a whole for generating the behavior of each hand separately.

The corpus striatum is the central organ of the behavior generator, and there are indications of special provisions for generating manipulative behavior. The corpus striatum, as we have seen, uses the active behavioral schema to combine the local image containing (as we shall see) the object image with a similar projection from the hand images and body image to issue precise motor commands to relevant parts of the body.

Since the object images are contained in the local image as their frame, they are supplied to the corpus striatum via their projection to the caudate nucleus, that is, as what the manipulative animal perceives.

However, in order to issue motor commands to the hands that coordinate their movements with visual input from objects in the scene, the behavior generator must be able to identify the parts of the visual input that are coming from the hands so that it can guide the hands in relation to the objects.

No such identification of telesensory input is required for locomotion, since the animal does not need to be able to see its body to move around in space relative to there objects.

But manipulation generally involves hand-eye coordination, and thus, in order to facilitate it, we should expect that the projection from the local image to the behavior generator circuit (via the caudate nucleus) would enable the animal to identify which part of the local image is coming from the hands.

This would account for the primate's new and highly unusual projection from area 9 of the prefrontal cortex, just anterior to the frontal eye fields, to the caudate nucleus. This is the only projection from the frontal neocortex to the caudate nucleus (where the corpus striatum receives the representation of the object).lxxxv It could provide markers in the local image indicating where the hands should be located. (There is, of course, no comparable problem using tactile sensations to control manipulation, because they have a fixed location relative to the hand and body images.)

Structural imagination requires the capacity to generate manipulation both overtly and covertly, and their effects on the brain must be parallel (despite being so different in their effects on the body), because in order for memory groups to have labels by which covert manipulation can recall them, those memories must have been recorded according to the overt manipulation that was causing them when they were received. That is how spatial imagination works, and now we are assuming that the same brain structure can also be used for as the memory system for structural imagination, that is, with manipulation and not just locomotion.

The crucial brain structure for imagination is the cingulate gyrus, which is part of the memory circuit (starting from the anterior temporal neocortex, proceeding though the hippocampus, fornix, and anterior nucleus, and then back to the cingulate gyrus, which has rich interconnections with adjacent areas of neocortex). Since the behavioral output system contains four hand images within its body image, the hand images have the same connections to the cingulate gyrus as the body image used in spatial imagination, and they have similar effects.

Both hand and body images for overt behavior project from the frontal neocortex to the anterior cingulate gyrus (by way of association fibers from the motor and supplementary areas), and both the hand and body images for covert behavior also project from frontal neocortex to the anterior cingulate gyrus (by way of the association fibers from the premotor neocortex and frontal neocortex where behavioral schemata are stored and activated).

The anterior cingulate gyrus is (agranular) motor-type neocortex, like the rest of the anterior neocortex, and it projects to the posterior cingulate gyrus, which has rich interconnections with the sensory and parietal areas of neocortex in the posterior cerebrum. Since both anterior and posterior regions of the cingulate gyrus are part of the memory circuit, it is likely that the cingulate is where images are recorded in sequences with behavioral labels for both spatio-temporal and structural imagination.

In the case of structural imagination, the only difference (apart from effects on images in the sensory input system) is that the behavior is manipulative, rather than locomotor. That is, when object images are recorded in memory, behavior is overt and object images are recorded with labels indicating the kind of manipulative behavior, and then, when behavior is covert (and the projection to the anterior cingulate gyrus from the hand and body images for overt behavior is not active), there is still input to the anterior cingulate indicating the kind of behavior (via the projection from the premotor and frontal neocortex). Thus, covert behavior gives the anterior cingulate gyrus sufficient information of the right kind to call up memory groups by their behavioral labels.

It should be emphasized, again, that most of the detailed neural connections required for the memory labels can be acquired from experience with the world, since the late phase of neurological development, called “learning,” is a contained form of reproductive causation in which behavioral schemata evolve gradually in the direction of greater power to satisfy desires by a form of natural selection through reinforcement.

That is, when a behavioral schema is successful in generating behavior that satisfies some desire, the memory circuit (using criteria built into it with its close and ancient connections with the seat of desire) ties the active neurons in every area of the neocortex together in a memory group (by the growth of synapses among them), so that when some significant portion of them is activated again, the whole group of neurons tends to fire. This occurs not only in the anterior and posterior neocortex, but also in the cingulate area and its connections to them.

Thus, when behavioral schemata that are responsible for successful actions on objects are naturally selected, connections are established through the cingulate gyrus between the kinds of behavior involved and the images of the sensory input system that are involved so that those images are labeled by the relevant kind of behavior. The labels are simply part of the behavioral schema that is naturally selected by reinforcement.

Such labels can, as we have seen, become generalized as abstract, intuitive concepts about the structure of space and the geometrical structures of object in space whose meaning is spelled out by how sequences of images represent the effects of locomotion and manipulation.

What makes structural imagination different from spatial imagination is that, instead of covert locomotion and turning calling up local images in sequences to represent their effect, covert manipulation (such as rotating or bending the object) is calling up telesensory and tactile images of object in sequences to represent their effects. But that difference means that they must have different effects on images in the sensory input system, and thus, it remains only to see how the object image is installed.

The sensory input system. In the sensory input system, the higher level of neurological organization should show up as a new capacity for representing objects within the local image that keeps track of how the geometrical structure of each is affected by rotation, translation, and other forms of manipulation. There is evidence for such object images in the memory circuit, but in order to see what is different, let us begin by recalling how the local image is constructed in the subjective animal system of representation and consider what is added in the manipulative animal.

The telesensory images registered in the sensory neocortex (the striate neocortex for vision and the superior temporal neocortex for hearing) are assembled as parts of a local image, as we have seen, in the inferior parietal neocortex, using projections from the body image as input about the current bodily condition.

In primates, however, there is additional input about the current bodily condition, because the body image now contain four hand images, each with its own somatosensory input. This information is used in a new way to construct the local image, because it reveals the shapes (and certain other properties) of objects in the local scene as well as their precise locations. Touch is a new (extroceptive) sensory modality, along with the other modalities, and its tactile images must be assembled as part of the local image as well. Somatosensory input from the hands is transformed into tactile images in the superior parietal neocortex, posterior to the somatosensory neocortex, and its connections to the inferior parietal neocortex make it possible to include them as another part of the local image, along with visual and auditory images.

The inferior parietal area also receives information from the frontal eye fields about the direction of fixations of the eyes, so that visual images from the different fixations of the eyes can be assembled into a visual appearance of the whole scene. There is evidence from primates that fixations of the eyes mark targets for manipulation in the representation of the current scene before it is projected to the behavior generator (that is, to the corpus striatum by way of the caudate nucleus).lxxxvi

Furthermore, there is abundant evidence that local image is required in order to guide the behavior of the hands in relation to objects. The object image is contained by the local image, just as the object itself is located in the local scene, and the local image is assembled in the inferior parietal neocortex. Lesions in the inferior parietal lobe of one hemisphere may cause subjects to neglect entirely the limbs on the side of the body it controls. Even when the hands are not paralyzed by the lesion, patients may be unable to locate objects on that side of their bodies or to identify them by touch (or visually). Lesions may show up, however, only in the inability to put one dimensional units together as a two dimensional configuration, for example, when drawing.lxxxvii

The local image is, however, just the frame for the object image. Structural imagination calls up sequences of telesensory and tactile images of objects within the local image according to the kind of covert manipulation. (Imagine turning a cup of water upside down.) Thus, the object images themselves must be handled in a different way from local images by the sensory input system. They must be contained in the local images like objects contained in the kind of space that mammals can understand. There are four pieces of evidence that the posterior cerebrum contains the new way of handling images that we expect.

(1) There are two changes within the memory circuit itself that suggests that images are being recorded as groups in a new way. The object image needs a new pathway, because its telesensory and tactile images must be recorded as groups separately from the local image if the later is to serve as its frame. The hippocampus, which is the staging area for forming neurons into memory groups, projects by way of the fornix to the anterior nucleus of the thalamus, which is basically a relay back to the cingulate neocortex. But this projection divides into two pathways, one that passes through the mammillary body and thence to the anterior nucleus, and the other that proceeds directly to the anterior nucleus. In primates, the later, direct pathway is relatively larger than in other mammals. The former, indirect pathway must be responsible for the local image, because the mammillary bodies are known to be essential to spatial orientation. If the images being processed through it were all oriented as part of the local image, then the images passing through the direct pathway could be processed independently of the local image, as if the local image were its frame.

(2) There is further evidence that the expanded, direct projection of the fornix to the thalamus is for processing the object image, because it sends fibers not only the anterior nucleus of the thalamus, but also to a new (or expanded) nucleus of the primate thalamus, the lateral dorsal nucleus. The lateral dorsal nucleus is only indistinctly separated from the anterior nucleus and appears to be a posterior extension of it. The lateral dorsal nucleus has two-way connections with the cingulate gyrus, parietal lobe and, perhaps, even the occipital cortex. Such direct connections with the parietal and occipital cortex are not found in other mammals, but they would make it possible to connect the separate object image to the local image as its frame. The result would be that the object represented by the object image would appear to be located somewhere in the local scene represented by the local image, that is, as located in the space of which subjective animals have a conception.

(3) Just posterior to the lateral dorsal nucleus of the thalamus is another thalamic nucleus newly prominent in primates, the lateral posterior nucleus. It projects to the superior parietal neocortex, where tactile images are analyzed, and that suggests that its function is to help integrate tactile images as parts of the object image, rather than the local image. The lateral posterior nucleus has connections within the thalamus to the pulvinar, which projects to the inferior parietal (and occipital) neocortex, on one side, and with the ventral posterior nucleus, where somatosensory input is relayed to the hand images, on the other side. Thus, its function seems to be connected with manipulation, just as the object image would require.

(4) Finally, there is a new, direct projection found in primates from the anterior temporal neocortex to the pulvinar.lxxxviii The anterior neocortex is the staging area for all input to the hippocampus and the only area of neocortex that does not receive a projection from the thalamus, and thus, it contains information about both the local image and the object image. The pulvinar, to which it projects, is the nucleus of the thalamus (just beneath the lateral dorsal nucleus) which projects to the parietal and occipital cortex, where the local image and the object image are processed. It is, therefore, a new circuit through the neocortex and thalamus (from the parietal/occipital neocortex to the anterior temporal neocortex to the pulvinar and back to the parietal/occipital area), and its function could well be to integrate the object image into the local image.

There are various ways in which these circuits might work in detail, but taken together, these four prominent changes in the posterior primate cerebrum are just what the sensory input system would need, if it were able to processes telesensory and tactile images as parts of an object image independently of the local image. They can be taken as evidence, therefore, of the new circuit between the object image and memory depicted as contained by the local image in the functional diagram of the manipulative animal behavior guidance system.

Nor is there any reason to doubt that the object image can handle as many objects as there are handles, which would put it on a higher level of neurological organization in the same way as the behavioral output system.

These differences between (higher) primate and non-primate brains suggest just the kind of higher level of part-whole complexity we would expect of animals with a structural imagination that have evolved from subjective animals. It seems that there are multiple channels through the behavioral output systems of the subjective animal system of representation which could be handling each of the hands separately as parts of the body as a whole. And there is a new way of representing the objects they manipulate as part of the local image. Thus, the cingulate neocortex has connections to both systems of just the right kinds needed to record and recall sequence of telesensory and tactile images as object images according to covert manipulation. Since this way for random variations to try out a higher level of neurological organization is not problematic, given that chordates sets up nervous system using 2-D arrays of neurons as units, we may take this as evidence that such a level of neurological organization is possible. Since it is possible, we infer that the evolution of animals like higher primates is inevitable.

The gradual evolution of primates.That primates are more powerful than other mammals in the way that is implied by having structural imagination is, perhaps, patent in the vast superiority of their hand-eye coordination, but there is not much data about their cognitive capacities.

The most famous evidence of structural imagination is Kohler's ape, which put one box on top of another in order to be able to use a stick to reach a banana. Moreover, when monkeys or apes are provided with paints and a canvas on which to paint, they enthusiastically construct geometrical structures of bright colors, whereas other mammals do not. It has been obvious for so long that they like to play with unchanging geometrical structures of matter that such behavior is often called "monkeying around" with them.

But more systematic evidence is conceivable. Primates should be able to count (or keep track of) more objects in the current scene than other mammals. And a properly trained primate should be able, for example, to tell how an object is oriented after a series of rotations. That is, if a primate were conditioned to pick out a distinctive face of a die and the die were rolled, then it should be able to learn to point to the side of die that the distinctive face is on, even when it cannot be seen. But other mammals should not be able to do so. Or primates should be able to pick out from a group of similar objects the one that is the folded up version of a pattern laid out flat, as in standard tests of spatial imagination, while other mammals cannot. Experiments like these would show that primates can make the inferences implied by the mechanism described in the last two chapters as structural imagination.

Evidence that primate evolution is due to the greater power afforded by structural imagination can also be found in the history of evolution, although it may not be obvious at first, because it seems possible to explain primates a mere adaptation to a special habitat. That is, it might be argued that the evolution of primates from mammals can be explained on the model of the evolution of amphibians from fish, of reptiles from amphibians, or of birds from early dinosaurs. In these cases, as we have seen, there is no change in the part-whole complexity of the nervous system, but merely an adaptation of the same kind of animal behavior guidance system to new habitats — to life on land and in the air. In other words, the significant changes occurred in the body, not the brain.

Living in trees is certainly a special habitat, and there is no doubt that primates have bodily characteristics that are well adapted to it. All primates have hands that are capable of grasping structures on trees. They all have acute binocular vision, with both large eyes directed forward. More generally, they are active and restless animals which react quickly to stimuli.

Living in trees is not, however, just a specialized environment. It is also a more demanding environment in which the power that comes from structural imagination would be richly rewarded. Arboreal life is surely possible without having a structural imagination. Indeed, the earliest ancestors of primates probably did not have structural imagination. They stem from which all the species of mammals radiated were insectivores, and primates are more closely related to those insectivores than any of the other classes of mammalian species (except possibly bats). The species from which primates are thought to have evolved has a living remnant, the small, primitive tree shrew (Tupia), and it is highly unlikely that tree shrews have a structural imagination. But given the demands of their arboreal habitat, this lineage of mammals must have had a "need" for structural imagination, if the required random variation was within the range of those being tried out, for it would have made them more powerful animals. And the need would account for the evolution of structural imagination, given that evolutionary change is how reproductive cycles add up in space over time. That means, however, that there must be some juncture in the evolution of primates at which it was added.

There is, indeed, fossil evidence of such a development, for there have been two radiations of primates in forests. The first radiation was that of the prosimians, represented by lemurs and tarsiers, about 65 million years ago during the radiation of mammals. Then there was a second radiation, the anthropoids — represented by the New World monkeys, the Old World monkeys, the great apes and humans — roughly 40 million years ago. As a result of the first great primate radiation, there were lemurs as large as chimpanzees, and anthropoids are thought to have evolved from lemurs of some kind.

Although prosimians typically have elongated flexible limbs with grasping hands and adhesive pads for grasping branches firmly as well as binocular vision, there are marked changes in anthropoid primates. Anthropoid eyes are directed forward more completely. Most anthropoids are able to sit in an upright position, which frees their hands for manipulating objects. The thumb is set apart from the other digits more extremely. Arm joint, elbow and wrist are capable of more rotation, so that the hand can be rotated in all directions possible in space. These are indications of a new capacity for manipulation, beyond a mere grasping reflex, which is probably all that prosimians have.

Moreover, only a general increase in power can explain why the radiation of anthropoid primates replaced prosimians in all but the lowest-energy ecological niches. It cannot have been tapping a new source of energy, because primates of all kinds eat almost anything edible in their habitat.

The actual history of the evolution of higher primates confirms, therefore, that they are a later stage in the evolution of multicellular animals, with a higher level of neurological organization. They are not merely better adapted to their environment, but inherently more powerful as animals. Thus, we would expect a primate radiation out of the forest. Much as mammals took over the high-energy ecological niches once occupied by dinosaurs, anthropoid primates should invade ecological niches outside the forest, displacing less powerful animals from those sources of free energy.

The almost complete absence of anthropoid apes from ecologies other than dense rain forests does not show, however, that there has not been a radiation of primates. Human beings are a kind of anthropoid primate that are adapted to tapping energy in this new environment. Although they have occupied all the other ecologies on the planet, they are not a mere radiation of primates, because they are so powerful that their radiation is now even displacing the great apes from their original environment. The primate radiation into the grasslands occurred long ago and has already led to another stage of evolution, which has already displaced anthropoid apes from this new environment. Indeed, as we shall see, the evolution of human beings involves such a revolutionary change that it starts yet another ladder of evolutionary stages in a different direction — as different from the stages of neurological evolution as those stages are from the stages of biological evolution.

8 Linguistic stage (primitive spiritual animals).We have followed the series of levels of neurological organization, tracing how multicellular animals evolve, stage by stage, from somatosensory animals, through telesensory and subjective animals, to manipulative animals. In each case, the increase in animal power came from increases in the capacity of the animal system of representation to internalize spatial aspects of the world. We now take up the final three stages of evolution leading up to beings like us. Though they continue the series of stages caused by levels of neurological organization, they also involve something quite novel. Each of these last three stages is also caused by a higher level of neurological organization, but they are levels of organization in a linguistic system of representation, and the function of language is not just how it increases the power of individual animals, but also how it increases the power of groups of individuals. What is novel about these stages is that they are also the evolution of spiritual animals.

The linguistic system of representation is built on the animal system of representation, but it does not increase the power of individual animals, at least, not originally. Just as higher levels of neurological organization introduced, first, spatial imagination and, then, structural imagination, to the animal system of representation, so each of these three yet higher levels of neurological organization introduces new forms of imagination in the linguistic system of representation (naturalistic, rational and philosophical imagination, as we shall see). And just as the new forms of imagination in the animal system of representation made individual animals more powerful by enabling them to adapt their behavior to spatial aspects of the world, so these new forms of imagination in the linguistic system of representation do eventually make individual animals more powerful by enabling them to adapt their behavior to further aspects of the world. However, such contributions to the power of individual animals are, at most, only half of the story. (The new forms of imagination in the linguistic system of representation are the blue panels in the accompanying diagram.)

The linguistic system of representation is not just a new kind of imagination in the individual, but also a new form of interaction among individuals. Linguistic interactions among individuals make groups of animals more powerful as a whole, and that is the original function of language, from which the increase in individual power derives. Indeed, it is a source such great power that groups of language using animals constitute animals on the social level of biological organization. It is, as we shall see, a new form of life, and such groups will be called “spiritual animals.”

What makes these final three stages different from all earlier stages is that organisms are evolving on two levels of biological organization at once. Not only do individual members, by their reproduction, impose natural selection on themselves at the individual level, but the social level animals they constitute impose natural selection on themselves at the social level by their reproduction at the social level. Thus, gradual evolution during these final three stages is change in the direction of the natural perfection of organisms at both levels of biological organization at once. And since they evolve together, there is also a natural perfection about their combination.

To mark this difference, these final three stages will be called “spiritual stages of evolution,” distinguishing them from the multicellular animal stages of evolution just discussed, and the animals evolving on the social level will be called “spiritual animals.” The appropriateness of calling the “spiritual” will be explained after we explain the function of language.

Since these final three levels of neurological organization are also stages in the evolution of a new kind of organism on the social level, the first stage has two ontological causes at once, according to this ontological explanation of evolutionary stages as a revolutionary global regularity, both a higher level of neurological organization and a higher level of biological organization. Once spiritual animals have evolved, subsequent evolutionary stages are caused ontologically by higher levels of neurological evolution in the individual multicellular animals, though their higher levels of organization are also evident in the linguistic representation they exchange.

Primitive spiritual animals.Primitive spiritual animals are groups of primates with the capacity to use a language of natural sentences (that is, sentences with a simple subject-predicate grammar). The use of language is functional, as we shall see, because it enables their behavior to be coordinated so that they can act as a whole. It is a new animal behavior guidance system that is possible only at the social level of biological organization. But language requires a higher level of part-whole complexity, the linguistic level of neurological organization, and such a higher level is possible, as we shall see, because it evolves within the faculty of imagination. The new form of imagination, called “naturalistic imagination,” gives subjective animals the conception of a state of affairs in the natural world, and that enables them to understand efficient causation.

Rational spiritual animals. Rational spiritual animals are also animals at the social level of biological organization, but they have the capacity to use psychological sentences (that is, sentences with predicates formed of verbs of propositional attitude, such as “believes” and “desires,” together with complete sentences). We shall see what its original function was, and how it too was possible because of a higher level of neurological organization in the faculty of imagination. It is aptly called the reflective level of neurological organization, because this higher level brain gives subjective animals the conception of a psychological state and enables them to think about such states as causes of behavior (and belief). The new form of imagination it gives them will be called “rational imagination,” because as they use psychological sentences to think about the causes of their own behavior, the causes of their behavior become reasons. (Reasons are causes of behavior that are represented as causing behavior as part of the very process of causing behavior.) Rational imagination gives them an understanding of rational causation, but since that enables them to understand arguments, it is also the foundation for a new form of evolution by reproductive causation, namely, cultural evolution, which is contained within spiritual animals. Thus, reason makes language a very powerful animal behavior guidance system, which takes over responsibility for behavior at both the individual and social level.

Philosophical spiritual animals. Philosophical spiritual animals are social level animals in which the arguments accumulated as culture have evolved a higher level of organization. That is, in philosophical arguments, all the arguments of the rational spiritual level are organized as parts of a single argument. That promises a new way of proving that propositions are true, and thus, it is a new way of discovering the true and the good, one that yields necessarily truths in one way or another. Though this is a stage of cultural evolution, it gives the members of the spiritual animals in which it exists a higher level of rational imagination, and thus, it is also the philosophical level of neurological organization. But there are, as we have seen, two ways of constructing such philosophical arguments, epistemological and ontological, and only one of them is able to succeed in the end.

Primitive spiritual animals evolve at the first spiritual stage of evolution. In order to show that a stage of evolution is inevitable, according to reproductive causation, it is necessary to show that the higher level of part-whole complexity in the structure of evolving organisms is both functional and possible.

The higher level must be functional in the sense of opening up an entire new range of powers for controlling relevant conditions, which can evolve gradually over the stage, and it must be possible in the sense that the higher level of organization can be tried out as a random variation in the evolving organisms.

In the case of primitive spiritual animals, however, there are two kinds of higher levels of part-whole complexity, a higher neurological level and a higher biological level, and the simplest way to explain their function is to assume, for now, that the linguistic level of neurological organization is possible, and to explain its origin by its functions, that is, by how it was naturally selected.

That will put us in a position to consider the nature of spiritual animals in the second section.

Only in the third section will I take up the issue about the possibility of the linguistic level of neurological organization, and that will include an explanation of the structure of the linguistic brain and how naturalistic imagination affords an understanding of efficient causation.

Finally, in the fourth section, I will consider the empirical evidence about the gradual evolution of primitive spiritual animals on earth.

Function of the linguistic level of neurological organization.The original function of a level of neurological organization higher than manipulative animals is a power it gave to entire groups of such animals, and thus, the easiest way to explain its function is to consider how spiritual animals evolved from animal societies. Thus, we begin with the radiation of primates. Such a radiation was inevitable, once higher primates had evolved, and it would lead some higher primates out of the forest, if it was possible, because that would open up new sources of free energy.

With the addition of structural imagination, higher primates were more powerful than other mammals, and though they started off simple, uniform and weak, manipulative animals gradually became more complex, diverse, and powerful. Such gradual evolution is change in the direction of maximum holistic power at both the level of the organisms and the ecology, which is natural perfection for organisms of their kind. Thus, as each primate species became as powerful as possible at controlling relevant conditions in its ecological niche, new primate species were added, dividing up the sources of usable energy and invading new habitats, and species generally adapted to one another, maximizing the use of the available free energy to fuel reproductive cycles generally. It was inevitable, because, as we have seen, reproductive causation always makes every possible increase in power actual.

Hominids. The radiation of primates beyond their original arboreal habitat was just a special case of species tapping new sources of free energy. As primates diversified to fill all possible ecological niches, some invaded the grasslands beyond the forest to tap the energy available there (such as grass seeds, berries and small animals). These primates evolved into hominids as their bodies and behavior became as powerful as possible in controlling the conditions that affected their reproduction in this new ecological niche. The traits that primates would evolve, once they invaded the grasslands, are predicable, in principle, because only a certain range of random variations can be tried out by their biological behavior guidance system and the conditions affecting their reproduction were fixed by their new ecological niche.

Carrying clubs. The main obstacle to occupying the grasslands were carnivores, such as lions and packs of wolves. The ungulates already inhabiting the grasslands protected themselves by traveling in herds and running away from these predators. But primates are relatively slow-moving, which made them easy prey. However, grasslands were not closed to them, because, as manipulative animals, they had another means of protection, not available to other mammals. They could carry clubs into the grassland with them and beat off carnivores that tried to prey on them.

Social life. This means of protection would be effective, however, only if several adults traveled together carrying clubs. Predators might still overcome one or two primates with clubs, especially if they were parents with children to protect. However, several adult primates carrying clubs could attack simultaneously from different directions, and that would thwart carnivores that were adapted to preying on ungulates, including not only the most ferocious, but also packs of smaller predators.

The need to stay together in a group would not be a great obstacle to their evolution, because group life in the forest had already given higher primates desires that enabled multiple families to live together in groups. They had instinctive desires that would establish a dominance hierarchy among them, and conflicts would be resolved by some members having power over others. Thus, grassland energy sources were open to any small group of primates that carried clubs and had learned how to wield them. This variation was well within the range of those being tried out randomly by existing primates, especially considering that, at first, nomadic primates could return to the forest at night for protection.

Since neither club-carrying nor social life was optional for nomadic primates, the evolution of two kinds of traits were inevitable, one a change in the biological behavior guidance system and the other a change mainly in the animal behavior guidance system set up by it.

Bipedal stance. The need to carry clubs entails the evolution of a bipedal stance in the primates that invaded the grassland. On the ground, primates were naturally disposed, like most mammals, to travel on all fours. And the further they could travel in gathering food, the wider the range of grasslands that they could invade. But nomadic primates could not travel on all fours, if they had to carry clubs along with them. As manipulative animals, however, they had another alternative. The precise control of muscles in their hands enabled primates to balance their bodies on two of their hands, leaving the other two hands free to carry clubs. Thus, the primates that invaded the grasslands would eventually acquire bodies suited to bipedal locomotion: random variations in embryological development that made them better able to balance their bodies on two legs controlled a condition that affected their reproduction and, thus, was selected as part of their biological behavior guidance systems. The primate predecessors of humans who walked upright, on two feet, are now generally known as “hominids”.

Although the traditional evolutionary explanation of bipedalism is also that it evolved for carrying things, this explanation is different. A century ago, Darwinians explained bipedalism by the need to carry tools. But that did not really explain bipedalism, because they attributed tool use to an increase in brain size or intelligence without being able to explain why an increase in brain size was necessary.

Sociobiologists have now dropped the assumption that brain size naturally increases, but their explanation does not make increasing brain size any more necessary. They claim that bipedalism evolved in order to carry the food required for the practice of food sharing. But that is no explanation, for they do not explain why hominids must share food. Apparently, increasing sociality has replaced increasing intelligence as the motor behind hominid evolution. (See, for example, Wilson and Lumsden 1983, pp. 10-12.)

To insist that the cause of bipedalism was the need to carry clubs for protection is not to deny that hominids also carried other tools. Nor to deny that they shared food. It is only to insist that bipedalism be explained by the function that made the trait inevitable, that is, by the one that predicts its evolution, rather than other functions which were made possible by its evolution. There is no reason to believe that bipedalism would have evolved to carry other tools or to share food, if nomadic primates did not have to carry clubs. And it would have evolved to carry clubs, even if it did not have those other functions.

Altruism. Another set of traits can be predicted by another function that needed to be served in their ecological niche. Protection from predators required not only traveling in groups, but also a disposition to use their clubs to assist other members of the group when they were endangered. Since this exposes the protectors to greater danger than sitting out the attack or running away, at least, in the short run, it is an example of altruism.

Altruism poses a challenge to explaining the evolution of nomadic bands of primates, therefore, because it seems that altruism cannot evolve by the natural selection of reproducing organisms. If individual animals are naturally selected by their success in reproducing, traits that benefit others at the expense of the animals conferring the benefits, then natural selection will eliminate individuals with those traits in favor of those who receive the benefits.

The altruism required of nomadic hominids resembles the bees’ use of stingers to protect the hive, but bees cannot be the model for explaining primate altruism. Defender bees die as they use their stingers to protect the hive, and that can be explained in social insects, because individual bees are parts of a multisomatic organism set up by way of a single fertilized egg cell. By including some members with stingers, the insect colony is able to do the non-reproductive work of protecting the hive as a whole. But hominid groups are not multisomatic organisms, because their member continue to reproduce sexually as individuals. Thus, another explanation is needed for the trait of protecting other members of their nomadic group.

The received solution to this puzzle about altruism is called “kin selection,” but it depends on a theory of evolution, called the “selfish gene,” which is incompatible with reproductive causation. The received view is, however, pointing to a relevant cause, which is explained in another way by reproductive causation. Though it does not quite explain the phenomenon of altruism in hominids, it will serve to introduce a cause that does make altruism inevitable.

What makes it appear that the gene is the unit of selection is, as we have seen, the sexual mixing of lower level structural causes in the process of reproduction, for it means that as organisms are evolving greater power, natural selection is focused on only certain of their genes (or chromosomes), which distinguish individuals from one another. Sexual reproduction is a way of internalizing reproductive causation so that lower level structural causes within the organism continue to evolve as the organism goes through reproductive cycles. And thus gradual evolution can be seen as genes competing with one another to appear in the next generation by the traits that are their non-reproductive structural effects, that is, as “selfish genes.”

The selfish gene theory explains altruistic behavior by the fact that siblings are likely to share the same genes. Thus, if altruistic behavior increases the likelihood of their siblings succeeding in reproducing more than it costs in terms of the animals own likelihood of reproducing, then the gene will be selected to appear in the next generation.

What the theory of kin selection of selfish genes is pointing to is another aspect of the evolution of the sexual mixing of genetic structures in reproduction. The obstacle to explaining the evolution of altruism is only an appearance that comes from failing to recognize that what is actually going through reproductive cycles, the primary structure, is not the individual multicellular animal, but the mating pair — or even the whole family.

The basic ontological cause of gradual evolution is, as we have seen, the reproductive cycle, because reproduction is what combines with space to make free energy scarce and that is how material structures that generate the whole cycles, including both reproductive and non-reproductive work, impose natural selection on themselves. But in the case of sexually reproducing animals, as we saw when the origin of sex was explained in eukaryotes (Stage 3), the individual animal is not that whole primary structure, because it cannot reproduce by itself. The individual organism must mate in order to reproduce, and that means, in effect, finding its other half. The mating pair is, therefore, the primary structure which is shaped by reproductive causation.

The primary structure is the “unit of selection,” and so the unit of selection is larger than the individual (rather than smaller, as the selfish gene hypothesis would have it), for it includes both members of the mating pair (though the pair that makes up a particular reproducing organism is not determined until they mate). Traits evolve in individual animals, because they help control conditions that affect the reproduction of the mating pair. Mating itself is the most obvious example of behavior that serves this function, but it includes, indirectly, at least, all the “sexually selected” traits required to mate, from suitable organs for the mating process to brilliant plumage in some male birds and fights over mates among male herd animals. Such genes can evolve, like any gene, because of their contribution to the maximum holistic power of the reproducing organisms of which they are part. It is just that the reproducing organisms of which they are part are the peculiar, disjointed primary structures of the kind entailed by sexual reproduction.

After the evolution of sex, therefore, what is evolving might be called a “composite organism,” or "composite primary structure," for the unit of selection is composed of more than one individual organism. And after the evolution of multicellular animals, the individual organisms may be in different generations. Reproduction is carried out by specialized cells, and thus, the mating pair does not necessarily die in reproducing sexually. Multicellular animals may, therefore, live side by side with their offspring, and when reproduction comes to depend on offspring being nurtured and protected by parents, the composite reproducing organism includes the whole family. The family is the primary structure that goes through the reproductive cycle (which is the ontological cause of gradual evolution), and traits evolve in its members because they control conditions that affect the reproduction of the primary structure as a whole.

Altruistic genes can evolve, like other genes, because they are structural causes of behavior in one, disjointed part of the primary structure, and they control a condition that affects the reproduction of the whole primary structure by promoting the reproduction of another individual organism of which the whole is composed. The disposition of children (and even grandchildren) to sacrifice for one another is just another way, along with caring for offspring, in which the same disjoint primary structure does the non-reproductive work that controls all the conditions affecting its reproduction as a whole. Like any gene, altruistic genes are working together with all the other genes of an organism to control all the conditions that affect its own reproduction as a whole. It is just that the primary structure, or reproducing organism in this case, is a collection of distinct multicellular animals.

Reproductive causation offers, therefore a ready explanation of altruism in the family (as an ontological explanation, if you will, of so-called “kin selection” on the “selfish gene” theory). But that is not quite an adequate explanation of the kind of altruism required for the existence of nomadic bands of hominids, because their protective altruism must extend beyond members of the family to primates that are not kin. Several families must band together in order to have enough adults for the protection of everyone, and in the long run, inbreeding among them is ruled out by its deleterious effects. As sociobiologists have noted, primates had already evolved mechanisms to prevent inbreeding, such as the disposition of young males to leave their home group at sexual maturity and seek mates in other groups, and hominids without some mechanism for spreading their genes beyond the nomadic band would not have been successful for long.

If strangers, rather than kin, are benefited by animals who sacrifice themselves altruistically, altruistic genes will make strangers who lack the altruistic gene more likely to reproduce, and that will make the primary structure (or “reproducing organism”) of which the altruistic individuals are part less likely to reproduce, given the scarcity of resources caused by population growth. A family of altruistic animals is likely to be invaded by “free riders,” who benefit from altruism without reciprocating, and altruism will be extinguished.

It is possible, of course, to conceive of mechanisms that would extend altruism beyond the family. For example, if altruism happened to be accompanied by a “tit-for-tat” policy of aiding only others who reciprocate, but not aiding those who do not, a group of altruistic animals would be able to resist invasion by “free riders.” Computer simulations suggest that such conditional altruistic behavior would enable altruism to evolve beyond the family. But to explain the evolution of an altruistic trait in a whole species in this way would require a series of different selection pressures whose origins remain unexplained. The altruistic gene must first evolve by kin selection in groups made up only of family members so that the “tit-for-tat” condition can be added later when for some reason family groups are joined by strangers. This is just the sketch of a possible explanation which depends on unexplained changes in the environment. In order to explain altruism among hominids, it would be necessary to fill in the concrete details of human evolution. And in the end, it would be merely a “just-so” story, which makes the evolution of hominids an accident.

There is, however, another explanation, which entails that the evolution of hominid altruism is inevitable. It is not an accident that the radiation of manipulative animals includes some that invade the grassland, because manipulation is only likely to evolve in animals living in trees. And their new ecological niche imposes a form of group selection on the nomadic primates. In other words, there is a primary structure, or "composite organism," that is even more inclusive than the family and is evolving by reproductive causation (though in this case, there are actually two units of selection (or primary structures), because the individuals or families continue to evolve by reproductive causation within them).

Under the conditions in which nomadic primates found themselves, there would be at least a weak form of group selection, and it would inevitably become stronger. What is needed is a disposition to protect other members of one’s nomadic band from predators even when the others are not members of one’s own family. Groups having some members who happened to be disposed to fight off predators, regardless who in the group was attacked, would be the groups that were most likely to succeed in acquiring energy-rich objects from the grasslands. Thus, altruistic protection of others from predators would evolve in individual primates.

The selection pressure at the group level was probably not very strong at first, because nomadic groups would tend to disband and regroup rather fluidly when they met or returned to forested regions where they were safe from predators. Groups that happened to have families with courageous altruists would be more likely to return whole, and that would tend to favor the altruists. The desire to carry clubs and protect others in one’s group would tend to evolve.

Group level natural selection would, however, become more powerful, because they would be less likely to disband. Groups with altruistic protectors would be more powerful in controlling relevant conditions as they formed bonds that made them stay together, because they would have established habits and routines that worked together more effectively in protecting against predators and controlling other conditions. And as groups became more powerful and more permanent, group level selection would become stronger, for they would eventually impose natural selection on themselves at the group level. Not only would the populations of those bands increase faster than those of other primates venturing into the grasslands, but the groups themselves would reproduce. Groups must divide up as their populations grow, because there is a limit to how many members can be sustained by the energy acquired from the amount of land that can be covered by wandering around. Hence, there would be organisms (or primary structures) going through reproductive cycles at two levels of organization at once: at the individual (or family) level and at the level of nomadic bands. And the reproducing organisms (or primary structures) on both levels would impose natural selection on themselves by their population growth and the scarcity it causes. Thus, while individuals continued to evolve functional traits that made them increasingly powerful as members of such groups, the groups themselves would evolve traits that made them increasingly powerful in controlling conditions which affect the reproduction of the group as a whole. That would include many traits in addition to the desire to protect other members of one’s group.

Limits of Social Coordination. Although motivating social, or even altruistic, behavior is not, therefore, an obstacle to the evolution of nomadic bands of hominids, there is nevertheless a severe limit on their power, because they are still just animal societies. This can be seen by analogy to multicellular animals.

On the individual level, animal power comes from two sources. One source is the size, shape, and strength of the body, and the other is the structure of its animal behavior guidance system. Both depend on its biological behavior guidance system, although the power of animal behavior comes from the geometrical structure it imposes on the motion and interaction of material objects in the region. We have seen how the animal behavior guidance system enables the animal to act on objects in space so that it structures the thermodynamic flow of matter from potential energy to evenly distributed heat.

On the social level, the power of a group has comparable sources. The size of its population corresponds to the strength of the body, and the mechanism for coordinating behavior corresponds to its behavior guidance system. Although in some ways, it is easy for the group to act as a whole on an object in space, say, by chasing it, there is a certain kind of structure that animal societies are not able to impose on the thermodynamic flow of free energy toward increasing entropy, even though it would make them more powerful. It is the coordination of members' behavior that would generate social level behavior like the behavior generated by manipulative animals. That is the function that explains the evolution of language.

What makes behavior animal behavior is that it acts on other objects in space, either to ingest energy rich object or for other purposes, and the function of the animal behavior guidance system is to adapt the spatial aspects of behavior to spatial aspects of the situation so that it controls the relevant conditions. Since the animal itself uses free energy to do work, the generation of bodily behavior is already one way of imposing a geometrical structure on the thermodynamic flow of matter in the region, and so when the body moves around in space and interacts with objects throughout the region, it imposes a further geometrical structure on the thermodynamic flow in the region. Manipulative animals are able to structure the thermodynamic flow even further by coordinating the behavior of its hands, and that points to the potential power of animal behavior at the social level: manipulative animal behavior is possible at the social level if the animal behavior of the members of the group can be coordinated.

Animal societies. By “animal societies,” I mean societies of animals, from schools of fish and flocks of birds to herds of ungulates and packs of wolves. Animal societies are so weak at the social level that they are not really animals at all. Groups of animals do have some power to control conditions in the world. It comes from the power of its members, and it can be increased up to a point by adding new members to the animal society. But animal power depends, because of the nature of animals, on adapting the spatial aspects of social level behavior to the spatial aspects of the situation, and that does not happen naturally in groups of animals. It requires a structural cause of some kind, that is, a social level animal behavior guidance system. Thus, the question is, Where is the material structure that would enable an animal society to behave like an animal on the social level? Or like a social-level manipulative animal.

The tendency toward randomness applies to animals like other objects that move and interact in the region. Solitary animals stay out of one another’s way, for the most part, and forage on their own, or, at most, in family units, so that the way their behavior adds up in space over time tends to even out their distribution in space.

To say that they are solitary is not to say that they are not social at all. Solitary animals often stake out territories from which to gather the energy they will need, and they defend it against conspecific intruders by a more or less ritualized fighting behavior.

Animal societies do exist, however, because some animals have instincts or desires that act like a force attracting animals of the same species to one another. Gregarious instincts are like gravitation, making the motion and interaction of such material objects adds up in space over time to the formation of social level objects in space.

But gregariousness results only in the minimal geometrical structure required to be a composite object in space, resembling gravitational objects, such as stars or drops of water, more than the kinds of material objects that can serve as structural causes. The disposition of fish to swim in schools and ungulates to run in herds are examples of such “gravitational” organizations at the social level. Though the members do not get very far apart, the spatial relations among the animals are continually changing at random.

In order to be a social level animal, the members of an animal society would have to act on objects at the social level like animals do at the multicellular level, and more power would come from acting like manipulative animals at the social level. Gregariousness itself is, perhaps, a way of acting as a whole. But its social level behavior is hardly up to the standard set by multicellular animals

In herd animals, the members’ desires to stay relatively close to one another includes the desire to start running when other members do. Thus, if the members also have the desire to run away from any predators they may spy, the whole herd will have protection from predators. Herd animals can usually run long and fast, and so as long as they run together, some members of the herd will avoid predation by outrunning any predators they may encounter. This is presumably the function of the herd instinct.

Leadership can make merely “gravitational” social level behavior more functional. Herd animals do not need a leader, because that role can be played by any member that happens to spy the predator first. But leadership can be useful to carnivores in acquiring energy. Wolves, for example, can all reliably attack the same animal, if they have a leader. Leaders are provided by dominance hierarchies. With the right kinds of conditional, instinctive desires, a competition or face-down among members can determine a “pecking order” among the members. The selection of goals for social level animal behavior is then centralized in a leader, and they can prey on animals that would be out of reach for individual animals, not to mention making it possible to settle conflicts among members over food or mates.lxxxix

Locomotion is about the limit of social level behavior in animal societies, because the other aspects of animal behavior, such as attacking prey and eating, are left up to the individuals acting in parallel. Societies of subjective animals are inherently more powerful than societies of telesensory animals, since they are less dependent on the inheritance of rigid instinctive routines for individual animal behavior. And group level locomotion can be more powerful with a higher level of neurological organization to guide it. Packs of wolves make better use of group level locomotion than flocks of birds, and groups of dolphins can use locomotion for purposes that are beyond schools of fish. But even societies of manipulative animals can only act in parallel with one another. Elephants, for example, may join forces in tearing down a tree, but even if they are manipulative animals, they cannot intentionally fold a tree into some shape like two hands working in different ways to produce a single result.

Need for social coordination. To put it positively, in order for animal societies to have animal behavior at the social level that is analogous to the behavior of even multicellular animals, it must be possible for the members to divide up tasks that work together as whole like different parts of an animal body, such as jaws working against one another to catch prey. This would be especially valuable for groups of hominids in acquiring food, since they cannot run fast enough to prey on herd animals like predatory carnivores. For example, if the group could make some members chase herd animals down a ravine where others were waiting to club them or roll rocks onto them, the group could kill animals that would be out of reach simply by chasing them. It would enable hominids to tap sources of energy that previously were available only by scavenging leftovers from carnivores.

The key to generating animal behavior at the social level is, therefore, coordinating the behavior of the members in a sense that involves a “division of labor” among the members. That would make the animal society more like the body of a subjective animals, for the animal society as a whole could adapt the spatial aspects of its social level behavior to the spatial aspects of the situation, much as different parts of a multicellular body are coordinated by motor commands to act as a whole on other objects in space.

Furthermore, such coordination of the members’ behavior in group action would be even more powerful, if the “motor commands” to different parts of the body were not merely instinctive, nor even discovered by trial and error, but designed in structural imagination to adapt the spatial aspects of social level behavior to the spatial aspects of the current situation, like primates coordinating the movements in different hands to attain a single goal.

Social coordination by the biological behavior guidance system. It is possible for the division of labor among the members on which coordination depends to come from the biological behavior guidance system, because the goals that animals pursue depend on the desires that it builds into them. But the biological behavior guidance system is not much help, because it cannot divide up labor very much, except by crippling social level animal behavior in another way.

In animal societies. It is possible for the biological behavior guidance system to give different members of the same species different desires, because in sexually reproducing multicellular animals, as we have seen, the unit of selection can be the entire family. When the organism going through cycles of reproduction is not just the individual, but the mating pair and its offspring, their behavior can be naturally selected for controlling conditions that affect the reproduction of the whole organism. Males and females can be given different desires.

In some African wolves, for example, the females have the desire to stay in the den and care for their young while the males have desires that lead them to hunt together in a pack, eat their prey, and return to the den and regurgitate food for their families.

More common are mating rituals and elaborate, ritualized fights by which males determine which of them will have access to females.

Likewise, the biological behavior guidance system can give parents and children different desires. We have seen how the peculiar disjointed nature of these “composite organisms” (or composite primary structures) can account for altruism among children and grandchildren.

Age and sex differences do not, however, afford enough division of labor to enable animal societies to act as social level animals. And even if it did, it would not divide up labor differently in different situations, because instincts are shaped only by natural selection of whole biological behavior guidance systems.

The maximum coordination in animal societies provided by the biological behavior guidance system is illustrated, perhaps, by the wild dogs of Africa. It is said that they can herd other animals in certain directions, using barking to coordinate their behavior, so that other dogs waiting for them can ambush the prey as they run by. This improbable geometrical structure in their social level behavior can trap their prey, like the limbs of a single animal body reaching out to pull energy-rich objects into its jaws, even though it is just how the motion and interaction of independent bodies add up in space over time because of the desires that motivate them. This is to add group level ingesting of energy rich object to locomotion in the repertoire of animal societies.

But like all instinctive behavior, it depends on the biological behavior guidance system, and thus, it still cannot be adapted to new situations except by the relatively slow process of biological evolution.

In multisomatic animals. There is one way that the biological behavior guidance system can impose a more complex division of labor. It occurs, as we have seen, in multisomatic organisms, such as insect colonies, where in addition to age and sex differences, members are determined to have different kinds of behavior by the pheromones, or messenger molecules, they encounter.xc But this mechanism of coordination requires animals to have specific locations in the geometrical structure of the whole organism in order for them to encounter the right pheromones at the right times. The unchanging geometrical structure is provided by a hive or labyrinth of tunnels. The pheromones are distributed to specific locations in the process of setting up the multisomatic organism, and in at least one mammal society as well as many insect colonies, it centers on a queen whose offspring populate the colony.

This possibility is exemplified by the blind mole rat of East Africa. Their reproduction is organized around queen, which is located at the center of a network of tunnels in the ground, and pheromones are distributed among them, determining different members to pursue different goals, by how they eat one another’s feces.

There is, in other words, a structural cause of animal behavior on the social level in multisomatic animals. But it is of no use to animal societies, because they have no unchanging spatial relations among the members. They are merely “gravitational objects” on the social level, sustained by gregarious desires, with the spatial relations among the members continually changing. To acquire a geometrical structure as a whole would constrain the motion and interaction of its members severely, for they would be sedentary and able to act only like moving parts in an otherwise rigid machine.xci

As mere animal societies, therefore, bands of hominids had only a limited capacity to generate social level behavior. The radiation of these primates into the grasslands made them bipedal. They carried clubs and may even have wielded axes to fend off predators that attacked them, including members other families. These traits were inevitable, and adaptation to membership in nomadic bands may account for other hominid traits. Though dominance hierarchies resolved conflicts and provided leadership, the need to remain in proximity to one another strengthened and refined social desires. And being manipulative animals, they could accumulate and pass on useful skills and habits (especially if they had the capacity to imitate one another’s behavior). As skill at wielding clubs increased, other tools were probably added, making it possible to hunt and kill larger game. They may have evolved group level hunting behavior as complex as wild dogs, and their structural imagination may have given them more complex signals for coordinating their behavior. They may even have learned to control fire. And the group level natural selection that nomadic bands imposed on themselves by the scarcity caused by their own population growth may have favored neurological refinements that account for the expansion of the brain. But since those nomadic bands were still just animal societies, hominids encountered the same limit on their power to generate social level behavior as other animal societies.

The original function of natural sentences. Though the evolution of wild dogs and societies made up of other merely subjective animals had to stop, once reproductive causation had made them as powerful as possible, the evolution of hominid society would begin a new stage of evolution, because primate imagination, with its capacity to understand structural causation, made a revolutionary change possible. That change was a new kind of animal behavior guidance system at the social level. But it was unlike the structural causes that had evolved to guide behavior at lower levels of biological organization. It was a primitive language.

Though in animal societies, social level behavior is never anything more than how the animal behavior of members with different desires (and, thus, different intentions or goals) add up in space over time, language is a mechanism that reaches inside each individual’s behavior guiding system and controls its animal system of representation. By connecting all these innermost mechanisms, language can give all the members of the group a single, common intention, and thus, even though they may all be performing different tasks, the group acts on other objects in space as a whole.

The reason that hominid society could evolve into spiritual animals, while other animal societies, such as packs of wolves and herd of ungulates could not, was structural imagination. Language requires a higher level of neurological organization, and it could be tried out as a radical random variation only on hominid brains.

How natural sentences coordinate behavior. Only a primitive language is needed to guide social level behavior. By a “primitive language,” I mean a language with “natural sentences,” that is, sentences with a simple subject-predicate grammar (or subject-verb-objects grammar). Natural sentences can refer to individual members and represent them as behaving in certain ways (or in certain ways in relation to certain other objects in space), and thus, a set of natural sentences, one for each member, can represent a plan for social level behavior by assigning different roles to different members. Here is how it would work.

In the beginning, the leader of the group would imagine a way of coordinating behavior in the situation that seemed to satisfy their desires, and he would assign roles to individuals by using natural sentences, in everyone’ presence, to describe how each member was supposed to behave. That public linguistic interaction would give the members a shared understanding of what every member was supposed to do in advance of acting. That is, each member would know not only what he was supposed to do, but what everyone else was supposed to do. Since members could play complementary roles in a common plan, the society could act as a whole on other objects in space and thereby control relevant conditions that were previously out of reach.

Coordinating behavior was not necessarily as simple as a leader telling each member what to do, because the use of natural sentences depends on imagination, which is a form of understanding by which animals can see what is possible. The manipulative animal system of representation uses images and how they change over time to represent regularities about change that are caused by the motion of objects relative to others and by the manipulation of objects, and since public utterances can control everyone’s imagination, every individual would be able to “see” the difference that each member’s behavior would make. By fitting those individual contributions together in “mammalian space,” each member could see what consequences they would have jointly in the situation thereby understanding how their behavior would attain some goal. The coherence of the plan would be tested in the process of adopting it, because each individual would understand what his own behavior was supposed to contribute to the plan and they would not be as inclined to follow the leader, if the whole plan or their role in it did not make sense to them.

Analogy to the multicellular biological behavior guidance system. There is a useful analogy to the multicellular biological behavior guidance system. The use of natural sentences to coordinate the behavior of individual animals resembles how the multicellular biological behavior guidance system coordinates the behavior of cells in constructing the bodies of multicellular (and multisomatic) animals. In both cases, a copy of the entire plan for the higher level structure is distributed to each lower level organism. Each cell receives a copy of the entire genome by the asexual reproduction of the fertilized egg cell in the process of embryological development, and each member of the spiritual animal receives the same plan of coordinated behavior by public, linguistic interactions in which the leader tells each member what to do. And in neither case will this means of coordination work, unless each member receiving a copy of the plan identifies itself with a different role in the plan, for otherwise it will not be able to generate the special kind of behavior required of it.

In the multicellular biological behavior guidance system, each cell can identify with a certain part of the genetic blueprint for the multicellular body because each cell has a fixed location relative to all the others in the process of embryological development. Different cells are determined to open up different segments of their chromosomes and generate different kinds of behavior by their locations in the geometrical structure of the body as a whole and the messenger molecules received there. (In insect societies, the process of development typically uses a “queen” to produce most of the multicellular members and construct a hive, and different members are determined to behave in different ways by the pheromones located where they find themselves in that structure.)

With the use of natural sentences, an unchanging geometrical structure is not necessary, because the plan is distributed by public linguistic interactions. The members all have animal systems of representation by which they are aware of the locations of one another’s bodies and other objects in the region, and thus, when the leader assigns different roles to different members, not only do the members construct the same plan of behavior relative to the same objects in space in their own faculties of imagination, but the members also identify each member with a certain agent in the plan, including themselves. Thus, different members intend to behave differently when the time comes, but their actions all fit together as a whole.

Contrast to animal signals. Even a primitive language is fundamentally different from the communication used in animal societies. Cries and screams of various sorts are used by other social animals, but such signs do not control imagination in the same way as natural sentences. Signals do enable them to communicate with one another and affect one another’s behavior, but they are inherently incapable of assigning tasks to members of a group.

Wild dogs of Africa use a system of different kinds of barks to coordinate their behavior in herding other animals toward the kill, and honey bees perform a dance by which those returning from a source of energy can indicate its direction and distance to other bees that are just departing. Such animal signals can be versatile, communicating different messages in different situations. As many as sixty different cries have been identified in societies of monkeys, and the hominid mouth and larynx were probably shaped by reproductive causation to generate many more kinds of signals.

But signaling cannot be used to assign tasks to individuals in advance of generating social level behavior, because signals and signs depend for their meaning on the locations of the animals sending and receiving them. Honey bees can communicate the distance and direction to the source of energy, but only because the other bees emerging from the hive already have the goal of traveling to a source of energy and they know to take the directions for locomotion as relative to the hive, the stationary body of the multisomatic organism where the signals are given. Monkey cries are also relative to the location of the signaler, for example, indicating where a certain kind or predator has been detected or where help is needed. Likewise, barking may coordinate the behavior of wild dogs relative to one another so that together they herd other animals in a certain direction, but the goals are fixed and the messages are part of an instinctive pattern that has been shaped to have this effect by reproductive causation.

This dependence of animal signals on the context of their utterance for the communication of their references and meanings makes them useless in assigning different roles to individual members in a plan of social level behavior. In order for animals to use verbal behavior to share a plan that divides up tasks among them, it must be possible, in advance of acting and regardless of its context, to refer to particular members and describe how each is to behave at a later time so that every member can understand who is to behave how and in what situations. That is what the simple grammar of natural sentences makes possible, and since animal communication lacks a grammatical structure, other animals do not have even a primitive language.

Contrast to animal societies. Language makes spiritual animals fundamentally different from animal societies, because the use of natural sentences is a structural cause for social level behavior. Animal societies have no structural cause for their social level behavior. Their social level behavior is simply how the behavior of members with possibly different desires (and, thus, different intentions or goals) add up randomly in space over time. The members act alongside one another, each pursuing its own goal.

The use of natural sentences is, however, a structural cause of social level behavior. Though there are no unchanging spatial relations among the members, they are in more or less continual linguistic interaction, and their linguistic interactions distribute to every member a plan for social level behavior toward some object in space in which each member is assigned a specific task that is designed to fit together with other members so that the group as a whole attain some goal. The result is a form of animal behavior, because it acts on other objects in space. That is, the group as a whole channels the thermodynamic flow of matter toward evenly heat to do work by imposing a geometrical structure on the region in ways that control conditions that affect their reproduction. Their social level behavior is a structural global regularity, and it has a structural cause, even though it is not a simple material structure.

The structural cause is the use of natural sentences, because that is what distributes the same plan of joint action to all the members, including the special instruction that informs each member about his special task. Since the behavior of all the members is represented in the imagination of each member prior to acting, the members of spiritual animals can be said to have the same intention. Instead of pursuing private goals alongside one another, they are all pursuing a single, shared goal. That is the sense in which the spiritual animal itself may be said to intend to behave in the way described by the plan.

That is, the spiritual animal works like a machine. With each member of the group playing a different role in their common plan, each member is like a moving part of an invisible machine whose motion and interaction is constrained by its location in that invisible geometrical structure of the whole machine. But what makes the machine invisible is that its structure as a whole is just the shared plan. The plan requires only that each member be able to imagine how all the participants will move and interact in the situation as a result of exchanging linguistic representations and act accordingly, and thus, the machine's structure is not only invisible, but infinitely flexible.

But since groups of language using primates have no body apart from all the independently moving bodies of its members, the social level animal can be said to have spiritual body. That is the reason for calling it a spiritual animal.

Contrast to multisomatic animals. Multisomatic animals, such as insect colonies, also have social level behavior generated by a structural cause, but it depends on having a physical body at the social level and that makes them less powerful than spiritual animals.

Since the unchanging geometrical structure of the multisomatic body comes from a hive or network of tunnels, their physical body makes them sedentary. However, the spiritual animal is not sedentary. It can move around as a whole and act on other objects in space like a manipulative multicellular animal on the social level of biological organization. It can, in effect, send different motor commands to different parts of its body, except that, with a spiritual body, there is no constraint on how each part can move and interact in relation to one another. It is as if its hands could manipulate objects without arms connecting them to the body.

Furthermore, in multisomatic animals, the coordination of members’ behavior is like an inherited instinctive routine, because it is determined by their biological behavior guidance system. The spiritual animal, on the other hand, has the use of the most highly evolved animal system of representation at the multicellular level to coordinate its behavior. It does not have to wait for instincts to evolve in order to adapt spatial aspects of its behavior to spatial aspects of the situation, as telesensory animals do. As long as the members have a desire to do what the leader instructs them to do, it does not even have to rely on trial and error to shape its social level behavior to fit situations, as subjective animals do, because structural imagination can be used in advance of acting overtly to design social level behavior so that it will control relevant conditions by how it fits together spatially with the other objects in the current situation. Different “motor commands” are sent to different parts of its spiritual body in the linguistic interaction by which the leader explains the plan. Thus, spiritual animals can generate novel, but appropriate kinds of animal behavior in the situation — much as Kohler’s ape did in using a stool and stick to knock down the banana, except on the social level.

Spiritual animals.The evolution of a primitive language marks, therefore, the evolution of a new kind of animal. But it is unique, because, according to this ontological explanation of revolutionary evolution, this stage of evolution has two ontological causes. Like previous stages in the evolution of multicellular animals, one ontological cause is a higher level of neurological organization, because what makes it possible to guide social level animal behavior is the use natural sentences. But since it is also the evolution of an animal at the social level of biological organization, another ontological cause of this revolutionary change is a higher level of biological organization. Being caused by higher levels of part-whole complexity in evolving organisms in two different ways at once is unprecedented in the course of evolution. And it makes what evolves at the first spiritual stage unique is other ways.

Unique kind of essential nature. The use of natural sentences to coordinate behavior in groups of hominids is a new animal behavior guidance system. Indeed, it is the new kind of animal behavior guidance system made possible by the social level of biological organization, just as the nervous system was the new kind of animal behavior guidance system made possible by the multicellular level. And as we shall see, it is only the first stage in the evolution of that animal behavior guidance system.

What makes animal societies so much less powerful than spiritual animals is that they not no behavior guidance system to guide social level animal behavior. They have only the animal behavior guidance systems built into their multicellular bodies, and their social nature, such as it is, comes from desires built into their brains that make them gregarious and, perhaps, set up a dominance hierarchy among them.

Insect colonies and other multisomatic animals do have behavior at the social level that is generated by a behavior guidance system, but it is a biological behavior guidance system, not an animal behavior guidance system. That is, insect colonies are what we called “anomalous animals,” because the only animal behavior guidance systems involved in generating their behavior exist in the lower level parts, the individual insects. Insect colonies are like sponges, except that being on the social level, they are made up of insects, rather than collar flagellates. Thus, they do not have animal behavior at the social level at all. They do not move around in space as a whole, nor do they act on other objects as a whole. Only the parts have animal behavior. Their social level behavior is like that of a plant, acting on the world as a whole or, at most, orienting behavior in an ambient field. In short, multisomatic animals have only a biological behavior guidance system at the social level of biological organization., and even that is only an extension of the multicellular biological behavior guidance system (or the mechanism of embryological development) to construct a multisomatic body on the social level in addition to the bodies it already constructs on the multicellular level.

Social level biological behavior guidance system. Spiritual animals do have animal behavior on the social level guided by an animal behavior guidance system, as we have seen. But the first indication of their unique kind of essential nature is that their animal behavior guidance system is not constructed by a social level biological behavior guidance system. At all previous stages in which animals evolved at a higher level of biological organization, their new kind of animal behavior guidance system required a structural cause that was constructed by their biological behavior guidance system, and thus, the biological behavior guidance system had to evolve first.

Multicellular animals had to evolve a mechanism of embryological development before there were animals with nervous systems on the multicellular level, because that is what constructs their nervous systems.

And in both prokaryotes and eukaryotes, the first behavior guidance system to evolve was a mechanism that could lead them through their reproductive cycles independently of the cycle of night and day. Only later did they evolve the capacity to acquire energy by ingesting other objects in space and the special mechanisms required to choose between incompatible kinds of behavior toward other objects in space, such as whether to ingest them or not. And those animal behavior guidance systems were both constructed and maintained by the capacity of their biological behavior guidance systems to coordinate the behavior of the lower level organisms of which they were composed.

Spiritual animals are, therefore, radically different, because they evolved a behavior guidance system for animal behavior at the social level without first evolving a social level biological behavior guidance system.

The lack of a social level biological behavior guidance system is not so puzzling when we think about them concretely, because we can understand how the use of a primitive language of natural sentences makes it possible to coordinate the members’ behavior in generating social level behavior. That is why I introduced spiritual animals by explaining the function of language in groups of primates. We can see that its evolution is inevitable, if language is possible. However, an ontological explanation of the stages of evolution cannot afford to overlook the curious nature of spiritual animals. The use of language is clearly a social level behavior guidance system, because it guides animal behavior on the social level in groups of primates. But it would be wrong to conclude that spiritual animals have no social level biological behavior guidance system at all.

The truth is that the use of natural sentences is also a biological behavior guidance system at the social level. Spiritual animals also go through cycles of reproduction in which they use free energy to do both kinds of work, the non-reproductive work of controlling relevant conditions as well as reproduction itself, and since they choose for themselves when to grow and when reproduce, they have their own biological behavior guidance system.

Their non-reproductive work is the social level animal behavior that explains why language evolved. The use of language is an animal behavior guidance system, or the structural cause for social level behavior, and animal behavior is a form of non-reproductive work.

The spiritual animal also reproduces as a whole. Indeed, reproduction is easy for spiritual animals, because it is just a matter of the group dividing into smaller groups which go their separate ways. And reproduction becomes necessary from time to time, because the members continue to reproduce on the individual level and spiritual animals eventually become too large to gather enough food for everyone by hunting and gathering by wandering around.

The division of the group can be generated by the instructions of a leader in the same way as other kinds of behavior, and when they divide, the smaller groups have all the same kinds of powers as they parent group. That is, each takes their primitive language with them, and the instinctive desires that lead to a dominance hierarchy gives each daughter group a leader so that it can do the non-reproductive work of acquiring energy and growing.

A new form of life.Since spiritual animals have all the characteristics that led us to believe that prokaryotes were the first living organisms, it seems that they must be considered a new form of life.

What marked the beginning of life, we decided, was the evolution of the first biological behavior guidance system, for that enabled the cells to go through reproductive cycles on their own, independently of the cycle of night and day. Since each cycle included non-reproductive work as well as reproduction, those cells had the kind of autonomous activity that is ordinarily meant by “living.” And we took this ordinary meaning of life to be ontologically significant, because it indicated a change in the ontological cause of evolution. It meant that natural selection was no longer imposed on them from outside, by the circadian cycle. Reproductive causation takes the cause of natural selection to be reproduction, because population growth leads to a scarcity of free energy that requires some reproductive cycles to come to an end. After the evolution of the first biological behavior guidance system, therefore, organisms imposed natural selection on themselves by their own reproduction.

Spiritual animals clearly have autonomous activity in the ordinary sense, for they generate both growth and reproduction on their own. And it has the same ontological significance as it did in prokaryotes, because their social level reproduction does mean that growth in the population of spiritual animals will eventually make resources scarce. They will eventually impose natural selection on themselves, and thus, like other forms of life, they will make themselves evolve. Their social level reproductive cycles will add up in space over time to a gradual change in the direction of maximum holistic power for organisms of their kind, which is natural perfection for organisms of their kind.

Spiritual animals might even be called the “third origin of life.”

Life first evolved when cell enclosed loops of DNA with a regulatory mechanism evolved into a biological behavior guidance system that led prokaryotes through cycles of reproduction independently of the circadian cycle.

But much the same thing happened again when colonies of prokaryotes that constructed aquatic balloons evolved a nucleus and were also able to go through reproductive cycles independently of the cycle of night and day. In both of these cases, life began with the evolution of a structural cause that could take over responsibility for their entire reproductive cycle.

That is also what happened to nomadic groups of primates when they evolved the capacity to use language to guide their social level animal behavior, for that was the evolution of a structural cause that would generate the reproductive cycles by which they would impose natural selection on themselves. Though in this case, the mold for their reproductive cycles was no the cycle of night and day, it was just as inevitable, because they were imposed by the reproduction (and, hence, population growth) of its members. With the evolution of natural sentences, choices about social level growth and reproduction were made by a behavior guidance system.

There is one aspect of spiritual animals that may make us reluctant to think of them as living organisms, though it does not disqualify them in the end. It comes from how spiritual animals are different from multicellular animals. Individual multicellular animals can have minds, but spiritual animals cannot.

By “mind,” I mean not merely a process of guiding animal behavior, but one with the unity of consciousness as well. We have seen how the behavior guiding process that occurs in brains gives rise to a form of matter whose intrinsic essential nature accounts for phenomenal properties, that is, the appearances that subjective animals have in perceiving the world, thinking about it, and feeling desires. (See Stage 6: Subjective animals: Unity of consciousness.)

Spiritual animals cannot be conscious in that sense, apart from the consciousness of its members. Disjointed, composite organisms cannot have neurons working together as in the thalamic projection to the neocortex like a massive complex antenna generating photons that register activity throughout the brain. Spiritual animals do not have conscious minds. But the assumption that such a subjective aspect to experience is essential to life may explain the reluctance to think of spiritual animals as living organisms.

It is not, however, sufficient reasons to deny that spiritual animals are a new form of life, for if it were, we would have to deny that prokaryotes and eukaryotes, plants and telesensory animals are forms of life. They do not have the unity of consciousness. But they are surely alive. Thus, I see no reason to deny that spiritual animal are a new form of life. The fact that they are made up of parts that are themselves living organisms, indeed organisms with the unity of consciousness, does not mean that they are not alive. It only points up how spiritual animals are unique in the course of evolution.

Lack of a social level material structure. What makes spiritual animals different from the evolution of life in prokaryotes and eukaryotes is that spiritual animals do not have any unchanging structure on their level of biological organization, except the more or less continual linguistic interaction among its members.

The members must continually interact linguistically, for that is what coordinates their behavior as parts of a higher level organism. But since the continual exchange of linguistic representations is the only unchanging geometrical structure that is required at the social level for the use of language to guide the behavior of the spiritual animal, it is provided by their gregariousness, which is due to the biological behavior guidance system of each individual member.

This is the reason for calling the new kind of animal at the social level of biological organization “spiritual” animals. The spiritual animal has no body of its own, except the bodies of all its members, and since a form of life that does not have a physical body is the traditional meaning of “spiritual,” it is appropriate to call these groups of language using primates “spiritual animals.”

Having a spiritual nature gives spiritual animals a great advantage when it comes to the efficiency of reproductive causation, because it means that natural selection is at work simultaneously on two different levels of biological organization. At the same time that the reproduction of spiritual animal at the social level is causing a population growth that imposes natural selection at the social level, the sexual reproduction of its members is causing a population growth within spiritual animals that imposes natural selection at the individual level. Simultaneously on two levels of biological organization, therefore, there is a gradual change in animals in the direction of natural perfection for organisms of their kind. As spiritual animals become as powerful as possible for animals made up of language using multicellular animals as parts, their members become as powerful as possible for animals that exist as parts of spiritual animals.

What makes this two-level gradual evolution possible is having a spiritual nature, because that makes social level reproduction easy. The members of a spiritual animal move around in space separately from one another, and so reproduction at the social level is merely a matter of subgroups separating from one another and going off in different directions, terminating their linguistic interactions with one another. That is what makes it so easy for language to serve as a biological behavior guidance system, given that it has the capacity to guide social level animal behavior.

The evolution of eukaryotic cells is analogous to the evolution of spiritual animals, except that eukaryotes have a material structure, or physical nature, rather than spiritual nature. The behavior of the lower level organisms is coordinated by enclosing them all within a cell, and thus, reproduction depends on dividing the cell and all reproducing all the lower level organisms of which it is composed. And since there are two lower levels of structural causes contained within the eukaryotic cell (the prokaryote-level chromosomes and the RNA-level genes of which chromosomes are composed), eukaryotes have a very complex structure, which taxes the capacity of reproductive causation to change in the direction of natural perfection. As evolving structures become complex, more random variations are possible, and eventually there is not enough time to try them all out. Their star will die first. Eukaryotes overcome this obstacle, as we have seen, by sexual reproduction. Sexually mixing their lower level structural causes as part of the process of reproduction focuses natural selection on those parts whose contribution to the whole makes the biggest difference to their power to control relevant at that point in their gradual evolution. Thus, instead of evolving by simple branching, like prokaryotes, eukaryotes can evolve as a species with a gene pool. And favorable random variations that occur in different members of previous generations can accumulate in individuals of later generations.

The advantage of having a spiritual nature is that no such special mechanism is required to focus natural selection on the lower level structural causes of which they are composed. Or rather, the way in which members mate outside their own group and migrate from one group to another means that a kind of “sexual mixing” is constantly going on in spiritual animals. Nor does the evolution of the parts depend on group level natural selection. Natural selection works to some extent on individuals within spiritual animal, because there are still conditions to be controlled within spiritual animals that affect their reproduction, and those who are better able to control them tend to leave more offspring.

The way that spiritual animals differ from organisms with a material structure makes them seem like what we called “composite organisms,” but they are something more.

We recognized the existence of composite organisms in discussing what is the “unit of selection” according to reproductive causation. We have seen how mating pairs and families are organisms that impose natural selection on themselves by their own reproduction and make themselves evolve. Even nomadic bands of hominids were composite organisms of a kind, since they were subject to group level selection. We called them composite organisms, because what goes through those reproductive cycles is not a material structure (with an unchanging geometrical structure), but a collection of material organisms.

Individual organisms are different from composite organisms because each originates from a single fertilized egg cell and they cannot be divided up without dying. Composite organisms are “dividual,” rather than individual, organisms. Though they can die, they do not necessarily die when they are divided up.

Spiritual animals are composite organisms by this test. They evolve by going through reproductive cycles and imposing natural selection on themselves at the social level. And they are “dividual,” because they do not necessarily die when they are broken up. Indeed, that is how they reproduce. But they are not merely composite organisms. Even though they do not have a material structure as a whole, they do have a structural cause of their social level animal behavior. It is a spiritual structural cause, and that is what is unique about spiritual animals.

Social and cultural aspects of the spiritual structural cause. Spiritual animals have a unique kind of essential nature, therefore, because the ontological cause of their social level behavior is a spiritual structural cause, rather than a material structural cause (or material structure). The spiritual animal is the new kind of animal that is made possible at the social level of biological organization stands, but it stands in stark contrast to all previous animal. Though it has biological and animal behavior at the social level, it does not have any unchanging geometrical structure at the social level to serve as its structural cause — except for the continual linguistic interaction of its members. That is, the use of language to coordinate the members’ behavior is its structural cause.

The spiritual animal has no body of its own, because with the use of language, it does not need a body to have a structural cause to serve as its behavior guidance system. Its only body is all the bodies of its members, which are in more or less continual linguistic interaction with one another. That is what earns the spiritual animals its name.

Since a form of life without a body is what has traditionally been meant by “spiritual,” “spiritual animal” is the appropriate name for the kind of organism that evolves from manipulative animals, that is, at the eight stage of evolution.

The use of language as a structural cause to guide social level behavior gives spiritual animals an essential nature that includes two kinds of structures, and it should be noticed at the outset, because it will play an important role in explaining the evolution of spiritual animals.

The use of language, as we have seen, is both a biological and an animal behavior guidance system for spiritual animals. It is able to serve both functions, because it generates social level behavior by coordinating the behavior of its individual members. That is, it does not need any material structure at the social level to serve as a structural cause for its social level animal behavior. But it does need the continual linguistic interaction among the members, and in that mechanism, there are two, fundamentally different kinds of structures, involving two fundamentally different kinds of part-whole complexity, which are essential to their spiritual nature.

The evolution of spiritual animals involves, as we have seen, higher levels of part-whole complexity in both ways that have been traced in this ontological derivation of the overall course of evolution in a spatiomaterial world: a higher level of neurological organization as well as a higher level of biological organization. Language has a nature that makes it essential to both.

The capacity to use language is the function of the higher level of neurological organization in the individual members, for, as we shall see, it a new way of manipulating “object images” in the “local image” and constructing “maps” of such “local images.”

But linguistic representations are not just constructs in imagination. They can be generated publicly by speaking, and their public manifestation is what makes it possible for them to coordinate the behavior of many different multicellular animals as parts of a higher level organism. Thus, this other aspect of language, its being public, is also essential to the nature of the spiritual animal.

Language is, therefore, what ties these two higher levels of part-whole complexity together as a single object in space with a new kind of essential nature, and that means that spiritual animals have two fundamentally different kinds of structures as a whole. In other words, the essential nature of the spiritual animal is uniquely twofold.

All the organisms and structures whose evolution we have traced thus far, including not only biological organisms and neurological structures, but also behavioral schemata, have essential natures that are defined by a single, material structure. I have called them “organisms,” or “reproducing organisms,” but they all involve a single way in which material parts are bundled together so that they go through reproductive cycles as a whole and impose natural selection on themselves.

But in the case of case of spiritual animals, two structures define their essential nature: how multicellular animals are combined as parts of a social level organism and how words are combined as parts of the sentences that they can all generate as public behavior. Both are aspects of the “organisms” that go through reproductive cycles and impose natural selection on themselves by their own population growth.

The structure that spiritual animals have because of their higher level of biological organization will be called the “social aspect” of spiritual animals, and the structure that spiritual animals have because of their higher level of neurological organization and the linguistic representations that they exchange will be called the “cultural aspect” of spiritual animals.

Social aspect.The social aspect is a structure of the spiritual animal as a whole in the same way as each higher level of biological organization involves a new structure. Lower level organisms are bundled together as parts of a higher level organism by coordinating their behavior. In the case of spiritual animals, they are bundled together in a way that does not require a specific set of spatial relations among them. But being in continual linguistic interaction is nevertheless a kind of structure, for it makes them all parts of a higher level organism. And as we shall see, that kind of structure is the source of its greater power as an animal and, later, makes it possible to for additional social structures to evolve because they generate social level behavior that controls some condition that affects the reproduction of spiritual animals.

Cultural aspect. The cultural aspect is also a structure of the spiritual animal as a whole, because what makes it possible for linguistic interactions to guide the behavior of the spiritual animal as a whole is that all the members speak the same language. The structure of language is a structure of the whole because it is a structure that is contained in each member of the spiritual animal. Its being located in each member is what makes it possible for one and the same structure to serve as both the biological animal behavior guidance system for the spiritual animal. The spiritual animal does not need a biological behavior guidance system that can set up a complex structure to function as an animal behavior guidance system, because that mechanism is contained in each of the parts and all that is necessary for it to generate group level behavior is that the members continually interact with one another linguistically. The cultural structure is potentially complete in each individual brain, and calling the linguistic structure “culture” anticipates somewhat the significance of this aspect. Not only are the two subsequent stages of evolution caused by higher level of part-whole complexity in linguistic representations exchanged as culture (that is, higher levels of neurological organization), but culture is itself capable of evolving by reproductive causation. That is the main source of increases in the power of spiritual animal to control relevant conditions.

The possibility of linguistic level of neurological organization.In order to show the inevitability of spiritual animals in the course of evolution, however, it is necessary to show not only that language is functional and can control relevant conditions that were out of reach for animal societies, but also that language is possible. From its function, we can tell that language must involve some form of overt individual behavior that others can observe and that it must be able to reach deep into their brains and control their imagination. The overt linguistic behavior must be able, therefore, to convey what the speaker is imagining so that the perception of that behavior by others causes the same content to occur in their imaginations. The overt behavior must, in other words, be a representation of the content of imagination.

As we have seen, however, such representations would have to be more complex than the signs used by other animals. Animals use cries and screams as signals to communicate with one another, and though they can be quite varied, they are inherently incapable of assigning tasks to members of a group. Their meanings and references depend on the context of their utterance, and that makes them useless in assigning different roles to individual members in a plan of social level behavior. In order for animals to use verbal behavior to share a plan that divides up tasks among them, it must be possible, in advance of acting and regardless of its context, to refer to particular members and describe how each is to behave at a later time so that every member can understand who is to behave how and in what situations.

In order for cries and screams to distribute the same plan of social level behavior to all the members, they must become organized with a subject-predicate grammar. At least two elements must be combined in each linguistic act, for it must connect an individual member with a specific way of behaving without relying on the context to identify either element. Hominids could associate particular cries with different members or other objects and different ways of behaving or other properties, but such signs must be combined in a certain way to serve as representations of a plan for their behavior in some situation. This is the function of predication, that is, taking certain signs to represent the objects and other signs to modify them in some way. But little more than predication would be needed, since the listeners can retain one instruction after another in memory and combine them all as parts of a single representation of the plan, and a series of such instructions would give every member an understanding of the whole plan. But if they had the capacity to communicate verbally how they were combining signs as subjects and predicates at all, it would be possible to complicate such utterances so that they also indicate the other objects and individuals to which the behavior is supposed to be directed, where it is supposed to occur, when, under what conditions, and the like.

The complexity of the behavioral schemata required for a primitive language can be estimated from the grammar of natural sentences in our own language. Even in sentences with a simple subject-predicate grammar, predicates are often themselves rather complex, with a verb and its objects to indicate how the action is directed at other objects in the world. (For example, if behavior is to be directed toward an object in space, the predicate will be a verb that takes a noun as its grammatical object, for example, “picking up a certain ax” or “going to a certain location”.) And complexity increases as these basic elements are modified by adjectives, adverbs, phrases and clauses, as would be needed to make clear what the individual is supposed to do. For example, “Pick up the sharp ax carefully and put in where the tools are kept.”

Repeated and varied uses of the basic mechanism of predication within single utterances may explain how all these elements can be included in natural sentences, but only if there is some way for listeners to tell how the speaker is combining them, for listeners must be able to construct the same representation in their imagination as the speaker’s. There is an asymmetry about the grammatical subject and predicate, and not only must it be clear from what the speaker says which sounds are to be treated as subjects and which as predicates, but it must be clear in each of the other phrases, clauses and modifiers based on predication. In other words, the cries and screams must be made with grammatical markers indicating how their meanings are to be combined in the listener’s imagination.

The linguistic system of representation. Considering the enormous range of possible natural sentences in our language, even a primitive language, based on a simple subject-predicate grammar, may seem too complex to be tried out as a random variations during the evolution of hominid societies. Unless there is some simple way in which the capacity for grammar could be acquired, it will not be clear that the evolution of language is inevitable, and it will not be plausible to hold that the our capacity for language is the result of a long series of accidental selection pressures that would probably not occur on other planets.

There is, however, a basically simple mechanism that could be tired out as a random variation on the primate brain, and it would account for such a primitive language. It is possible, because primates had evolved a faculty of imagination that included both spatial and structural imagination. The ability to use of language comes from the evolution of a linguistic system of representation.

The linguistic system of representation is different from the animal system of representation, because its representations can exist as public objects, that is, as sentences that are generated by overt verbal behavior.

But such a linguistic system of representation is possible only because it is constructed out of parts supplied by the animal system of representation. The manipulative animal system of representation already has a faculty of imagination (both spatial and structural imagination), and the ability to speak and understand linguistic representations comes from a higher level of neurological organization within the faculty of imagination of the animal system of representation. (That is, linguistic behavioral schemata are on a higher level of organization than locomotor and manipulative behavioral schemata, and the images on which covert behavior operates in the sensory input system are naturalistic images, which are compounds of local images and object images)

This new mechanism in the faculty of imagination would account for the “deep grammar” of “universal grammar” that Chomsky identified beneath the surface grammar of all natural languages. Chomsky argued that the remarkable capacity of humans to learn a language, including the ability to generate an indefinitely large range of sentences permitted in it, is best explained by a genetically inherited capacity, could not be explained as a result of operant conditioning (as B. F. Skinner had insisted). The surface grammar of a natural language is, as we shall see, simply the conventions by which the speaker indicates the kinds of covert behavior he is using to construct some representation in his faculty of imagination so that the listener can construct the same representation in theirs. What is universal, in other words, is a faculty of naturalistic imagination.

This explanation might also confirm a more controversial aspect of Chomsky’s position. Chomsky has puzzled many of his followers by expressing doubts about whether this genetically inherited capacity can be explained by Darwinian natural selection. What is bothering Chomsky may be the assumption of contemporary Darwinists that the details of this brain mechanism must be explained as an accumulation of traits a series of caused by a series of externally imposed special selection pressures. But it is not necessary to accept accidentalism to explain the evolution of language. The capacity for language could be another of the more revolutionary episodes in the course of evolution that are not recognized by contemporary Darwinists. If it is provided by a higher level of neurological organization, the advent of language would mark the beginning of a new evolutionary stage. Like all such radical random variations, it would start off simple, uniform and weak, and as a result of reproductive causation, the capacity for language would gradually become more complex, diverse and powerful. And as we shall see, one stage leads to another such revolutionary episode in which a yet higher level of neurological organization makes it possible to use psychological sentences and leads to reason.

What makes it possible for something as simple as a higher level of neurological organization in the faculty of imagination to account for language is the way that imagination is a foundation for the kind of learning that has been explained as a contained form of reproductive causation that takes place during a late phase of embryological development.

The trait that needs to be explained, as Chomsky insisted, is the remarkable capacity of individuals to learn natural languages of vastly different kinds, and that is explained as the evolution of behavioral schemata for generating covert linguistic behavior within the faculty of imagination in each individual brain by a form of natural selection that depends on reinforcement. (Skinner was not entirely wrong to think that operant conditioning was involved.)

The higher level of part-whole complexity in covert behavior marks them a linguistic schemata. But just as neurological development internalized spatial causation as spatial imagination and structural causation as structural imagination, so this contained form of reproductive causation internalizes the natural language used by the spiritual animal in the developing brains of its new members.

And as a byproduct, it gives language users a faculty of naturalistic imagination by which they can think about state of affairs in the natural world and understand efficient cause explanations. That is, they can see states of objects in space against the background of what is possible by efficient causation, either their possible causes or possible effects.

Verbal and nonverbal sides of linguistic representations.The basic social function of language is to represent in public behavior a certain kind of image that is constructed privately in each faculty of imagination. The (potentially) public part of linguistic behavior will be called “verbal behavior,” the words and sentences that can be spoken. But since the images in imagination are a form of representation based on the animal system of representation, the verbal behavior involved is actually just a re-representation of some kind of higher level animal representation.

The linguistic representation has, therefore, both a verbal and a nonverbal side. To show how it is possible for the verbal side, that is, overt verbal behavior, to represent the nonverbal side (or nonverbal covert linguistic behavior and the naturalistic images on which it operates as a higher level animal representation), I will consider how naturalistic images can be constructed in the faculty of imagination and then show how the nonverbal covert linguistic behavior involved in doing so can be represented publicly in overt verbal behavior. I will begin by focusing on how language is handled in the brain of the speaker and then expand on how it works in the brains of listeners who can understand overt verbal behavior.

Let us assume that the mouth and larynx are able to form the broad range of sounds needed for language, though that capacity is undoubtedly among the traits that evolved gradually during the primitive spiritual stage. We can also assume that hominids had the capacity to associate specific (complex) sounds with particular local scenes, particular objects in space, kinds of objects, and ways of behaving as their meanings, since this is a capacity that chimps have. Though that is not enough to explain how words and meanings are connected in the linguistic brain, it does allow us to see how language could evolve in the primate brain. It means that hominids could call up appropriate images in imagination when they heard certain sounds, or make those sounds when the images occurred to them.

The basic mechanism that needs to be explained is the subject-predicate grammar of verbal behavior, and its function can be explained by the meaning that is supposed to be conveyed by it. That meaning is the nonverbal side of the linguistic representation, and since it is a higher level naturalistic image that can be constructed in the erstwhile primate faculty of imagination, let us begin by recalling what is involved in spatial and structural imagination.

Local images are the telesensory images combined (according to input about the bodily condition) as a representation of the local scene relative to the animal’s body. Spatial imagination is the capacity to understand the effects of motion on the relations of objects in the territory by calling up sequences of local images by covert locomotion as well as the effects of motion in the local scene by calling up changes in the telesensory images of which it is composed. Thus, if words (as distinctive sounds) can be associated with such images at all, they can refer to (and re-identify) particular locations by way of local images and to particular objects in space by way of telesensory images in the local images. They can also refer to kinds of objects, or properties, insofar as those kinds can be recognized by telesensory images, including ways in which bodies behave. And they can refer to spatial relations among objects by way of the understanding of the structure of space through spatial imagination.

Because of structural imagination, however, objects in a local scene can also be represented by object images, which are sequences of telesensory images that can be called up from memory by covert manipulation that represent what happens to the object when it is manipulated in various ways. Object images can also be the meanings represented by words, enabling the words to refer not only to particular objects, but also to kinds of objects.

Suppose the leader devising a plan of social level behavior wanted some members to chase deer into a ravine and other members to roll rocks down on them as the deer ran by. He would think about members of the first group by calling up object images of them in his imagination by covert behavior, connecting those images with the (perceived or imagined) local image to represent them as being located in the field outside the ravine where deer are grazing. He would then call up another object image, this time of bodies running and yelling, and his covert linguistic manipulation would combine this second object image with object images of the members in the field, orienting their running and yelling in certain directions relative to the deer. Such combinations of local images and object images would create naturalistic images, or representations of objects in space as being related, moving or interacting with one another in such ways. The structure of imagination together with memory would supply sequences of images representing the changes that can occur, given the naturalistic states being picked out, and thus, the leader would, for example, have images of deer locomotion in response to the images of disturbances being caused. He could anticipate where the deer would run, and so on, allowing him to see what would happen as a means to his goal.

It is, however, one thing to think a plan and another to communicate it, and the latter requires the leader’s verbal behavior to enable others to construct the same plan in their imaginations. Even if the leader had words associated with the local images and with the object images of the members, the deer, and the behavior of chasing, that would not suffice to represent the animal representation he has constructed by his nonverbal (covert) behavior, for the listener must combine the meanings called up from memory by each word in the same way and there would be no way to tell how to do that.

References to the field in the local scene and the particular deer could, perhaps, be conveyed by pointing to them and using such words as “deer” and “field”, because pointing is public behavior and that would enable listeners to could construct representations of those objects in the local scene as objects of such kinds. But the leader could not communicate his plan for social level behavior unless his verbal behavior could control their imaginations so that they combined object images of the members being assigned the task with object images of the task being assigned to them. That is the function of grammar.

If there were a mechanism that would make the leader utter the words in a way that indicated which meanings were to be treated as grammatical subjects and which were to be treated as predicates, the listeners would be able to combine their own object and local images in the correct way. They would call up local images for the words referring to locations and an object image for each member named, and they would combine those object images with images for the kinds of behavior named, so that the listeners would also have a naturalistic image representing each member as behaving in a certain way.

In this case, however, at least three object images would be involved each naturalistic image, because members are supposed to chase the deer. Two of the object images would be treated grammatically as subjects of predication (the member and the deer) and one object image treated as a predicate (the relation of chasing), and all three would be combined in a certain order (together with local images for any references to locations) as a single naturalistic image.

Speaking: nonverbal behavior determining verbal behavior. The nonverbal (always covert) part of linguistic behavior — combining image with another as a naturalistic image of some state of objects in space (or event involving them) — may require some special mechanisms to handle the grammatical subject differently from the predicate, but it surely requires only a minor modification of primate imagination. Chimps that learn to associate words with certain kinds of objects spontaneously combine different words for the same object as a single new word, and thus, it is just a matter of evolving a behavioral schema that keeps the covert locomotion and manipulations straight. The key to the use of language is, therefore, the mechanism that makes the verbal side of linguistic behavior indicate how the images associated with the words are to be combined as a naturalistic image representing some naturalistic state of affairs.

Such naturalistic images are already a higher level of neurological organization on the nonverbal side of linguistic behavior, because it is a new way of “manipulating” object images. Instead of covert manipulations that call up sequences of telesensory images representing the effects of rotating the object, bending it, or putting objects with different geometrical structures together, covert linguistic manipulation combines different images as representations of the same object in the local image at the same time.

The nonverbal side of linguistic behavior may start with one object image for the object in the scene (the grammatical subject) and superimpose another object image (for a kind of object or way of behaving) on the same object in the scene. The result would depend on the object images, but since both meanings are various sequences of telesensory images, it would involve a sequence of telesensory images that depends on some sequence of images from both meanings. That sequence of images would be a naturalistic image, the potential meaning of a sentence or what is called a “naturalistic proposition.”

The naturalistic image could then be used as the grammatical subject to which further object images are added in a similar way (compounding predication within a sentence), or it could be joined in the local image by object images representing other objects in the local scene (conjoining different sentences as a description of the scene).

Such nonverbal covert behavior would require linguistic behavioral schemata with a higher level of part-whole complexity, but that is not all that is required by this higher level of neurological organization, because verbal behavior must also represent how the object images are to be combined. That is, verbal behavior must indicate two things at once, both the images involved and how they are to be combined as naturalistic images. Words for all the images involved must be uttered as part of a single speech act, called a sentence, and the kind of covert manipulation involved must modify the words in some distinctive way, by their order, inflection, prefixes, suffixes, or the like in the sentence.

The capacity to generate verbal behavior of this kind requires a new brain mechanism that does two things: it must connect each image (or “meaning”) involved in the nonverbal linguistic act with its name, and it must register which images are subjects and which are predicates in its construction of the naturalistic image(s) (or “meaning of sentence’). The output of such a center would be able to determine motor commands for verbal behavior that would indicate both aspects of the nonverbal side of the linguistic act.

Understanding: verbal behavior determining (effects of) nonverbal behavior. Linguistic interaction requires listeners who can understand the verbal behavior in the sense of constructing the same naturalistic images in their own faculties of imagination. This would require the new neural mechanism for verbal behavior to work in reverse. That is, instead of using input about the images and covert manipulation of them to generate verbal behavior for words with grammatical markers, it would have to use telesensory input of words and grammatical markers uttered by other to call up the images and combine them in imagination in the indicated way. That would be to construct the speaker’s naturalistic image, or proposition, in the listener’s faculty of imagination.

The structure of the linguistic brain. The evolution of the use of language involves changes that are located in only one of the two hemispheres of the forebrain. It is usually the right hemisphere that continues to serve spatial and structural imagination, which means that bodily behavior, including locomotion and manipulation, can continue to be generated with at least as much skill as primates. The left hemisphere evolves a higher level of neurological organization which is dedicated to linguistic behavior, both the verbal and nonverbal sides. Nonverbal linguistic behavior is a form of covert behavior that manipulates multiple local and object images to construct naturalistic images. They are the meanings of natural sentences, and there are special mechanisms in the left hemisphere for representing this nonverbal behavior verbally (labeled “Wernicke’s area” and “Broca’s area” in the functional diagram of the linguistic animal behavior guidance system). How this higher level is related to spatial and structural imagination is suggested by the functional diagram of subsystems in the linguistic animal behavior guidance system.

This diagram suppresses the arrows between the sensory input and behavioral output systems representing the basic connections that stem from the telesensory animal behavior guidance system (perception and the input to the local image about the current bodily condition). They are crucial to the mechanism for speaking sentences and hearing them as sounds, but they are not crucial to generating linguistic acts or understanding their meanings.

The higher level of neurological organization that constitutes naturalistic imagination occurs in both the behavioral output system and the sensory input system, repeating the kinds of changes that occurred in the evolution of structural from spatial imagination. But in this case, the new structure does not occur within the local image. Nor does it occur within the object image. It is, rather, a structure that includes both of them as parts, namely, the naturalistic image, which is the meaning of the natural sentence. (See the functional diagram of the linguistic animal behavior guidance system.)

In the behavioral output system, the higher level of organization is a kind of behavioral schemata used by the behavior generator that can linguistically manipulate images of all kind, including both local images and object images, in order to construct a compound representation in the sensory input system, the naturalistic image.

The naturalistic image is located in the sensory input system (mainly in a region of the inferior parietal lobe). The covert nonverbal linguistic behavior acts on this region in the same way as spatial and structural imagination (by way of the projection from the anterior to the posterior cingulate gyrus and the latter’s connections with the adjoining areas of non-cingulate neocortex).

Once again, the linguistic behavioral schemata used by the behavior guidance system are actually structure contained in the frontal neocortex, and it has access to them by way of a complete circuit (through the neocortex, corpus striatum and ventral anterior thalamus) which is not depicted in this diagram. This is at least one place where the structures internalized by the evolution of behavior schemata by reinforcement selection are contained.

From the function of language and the nature of the primate faculty of imagination, we have inferred the brain systems that are required for the kind of linguistic act that would enable a leader to distribute a plan of social level behavior to the members of a nomadic band. In addition to the higher level of neurological organization in the faculty of imagination, which make it possible for linguistic behavioral schemata to manipulate images of various kinds as the meanings of words used in constructing the meanings of natural sentences, the use of language requires changes in the nervous system set up by embryological development in order to generate the verbal side of linguistic acts and to recognize their meanings from telesensory images of another’s verbal behavior. They are the regions of the neocortex called Wernicke’s area and Broca’s area in the linguistic hemisphere of the brain.

Wernicke’s area has two different functions, translating the verbal behavior of other speakers that is registered as telesensory input into the naturalistic images that are their meanings, and translating the naturalistic images constructed by the speaker’s nonverbal linguistic behavior into words and grammatical markers so that they can be generated as the verbal side of linguistic behavior.

There is a major connection between Wernicke’s and Broca’s areas not represented in this functional diagram by which Wernicke’s area identifies the words and grammatical markers to be generated so that Broca’s area can, as part of the complete linguistic act, generate the motor commands for speaking the natural sentence.

The connections between Wernicke’s and Broca’s areas, as well as between them and the faculty of naturalistic imagination, can be seen better in the diagram of the linguistic brain. This diagram is looking down on the two hemispheres of the brain, with the linguistic mechanisms located in the left brain. The blue lines depict the causal connections involved in speaking, whereas the red lines in the left hemisphere depict the causal connections involved in listening and understanding sentences spoken by others.

Wernicke’s and Broca’s areas in the left hemisphere are known to play a central role in language, and the roles they have, as indicated by the effects of damage to each, suggest that they work together to serve the function required by this explanation of how language is possible. The verbal aspects of linguistic behavior are handled by Wernicke’s and Broca’s areas of the left (linguistic) hemisphere.

Wernicke’s area is located in a posterior region of the superior temporal neocortex, and damage to this area is known to make patients unable to connect words and their meanings. Given the meanings (or object images), such patients cannot call up their names, and given the words, they cannot identify their meanings.

Broca’s area is located in the frontal neocortex just anterior to the motor neocortex sending motor commands to the mouth, larynx, tongue, and lips, and damage to Broca’s area is known to make patients unable to arrange words with their grammatical markers as well formed sentences, though they continue to be able to understand sentences and suffer only limited loss of ability to produce the words for object images (meanings).

These two areas are connected by the arcuate fasciculus, a large bundle of association fibers that also connections the inferior parietal neocortex to the frontal cortex. It apparently transfers information from Wernicke’s area to Broca’s area, because the effect of cutting it is basically the same as damage to Broca’s area.

Speaking. Wernicke’s area has the function of connecting the verbal and nonverbal sides of linguistic acts. The speech act is generated by a linguistic behavioral schema in the frontal neocortex (as part of the behavior generator). It generates covert nonverbal manipulation in the anterior cingulate gyrus, and (by way of its projection to the posterior cingulate gyrus and the latter’s connections with the inferior parietal area), it constructs a naturalistic image in the sensory input system. The inferior parietal area, where the naturalistic image is constructed, has two way connections with Wernicke’s area, and so it can informs Wernicke’s area about how the naturalistic image is being constructed in naturalistic imagination. Wernicke’s area not only connects the various images with their names, but also registers how the words are being related to one another as grammatical subjects and predicates in each naturalistic image. Wernicke’s projection to Broca’s area provides all the information needed to generate the motor commands for verbal behavior, using the words with proper grammatical markers. The projection from Broca’s area to the part of the overt body image sending motor commands to the mouth, etc., would enable it to generate overt verbal behavior directly. Verbal behavior is, therefore, a result of an act of nonverbal imagination, though the behavior generator (with its linguistic schemata) in the frontal cortex could help Broca’s determine the actual surface grammar used in verbal behavior, when there are alternative ways of marking the words grammatically.

Understanding. Wernicke’s area also connects the verbal and nonverbal sides of the linguistic act in the listener’s brain. The location of Wernicke’s area next to the auditory analysis region of neocortex in the superior temporal lobe makes it easy to receive input about which words and which grammatical markers are identified in the auditory telesensory images caused by another speaker’s verbal behavior, and thus, with its two way connections to the inferior parietal neocortex, Wernicke’s area plays the role of the posterior cingulate gyrus in constructing the naturalistic image. That is, it acts as covert nonverbal behavior, except that it is reaching into the brain to control imagination by way of the public linguistic interaction. The meaning of the sentence is the naturalistic image, which is projected to the behavioral output system (by way of the caudate nucleus, globus pallidus, and the ventral anterior nucleus of the thalamus), so that it becomes part of the local scene in which the subject responds.

Since Broca’s area is not involved in understanding the meaning of a sentence (the proposition), that would explain why damage to Broca’s area does not affect language comprehension. The ability of such patients to name objects (that is, to generate the right word in for each object) is affected, but not completely impaired by damage to Broca’s area. On this account, naming could be explained as repeating sounds heard in auditory imagination. Wernicke’s area would still connect the image and with the word, and so a reverse connection back to the auditory area would provide a telesensory image of the spoken word, enabling the patient to repeat the word without any help from Broca’s area..

Understanding a sentence heard would not require any covert nonverbal manipulation. (But it would be possible for the listener to reconstruct the naturalistic image in his imagination by repeating the sentence to himself, since the behavioral schema for the nonverbal manipulation to generate the sentence would probably be connected in memory with the verbal behavior in speaking it.)

Though understanding linguistic representations does not necessarily involve any covert nonverbal manipulation, language learning still depends on acquiring linguistic behavior schemata for speaking, including covert nonverbal manipulation, because the connections in Wernicke’s area between object images and words and between linguistic manipulations of them and grammatical markers are acquired as part of those linguistic behavior schemata (along with the capacity to generate the right motor commands for the verbal side of the speech act). Without learning to speak, memory might not even contain the images that are to be combined in the naturalistic image.

Understanding sentences would require additional learning, because Wernicke’s area must be able to use telesensory images of the words and grammatical markers used by others to call up the images and control how they are combined in the naturalistic image. However, such learning would be all but automatic, because in learning to generate the verbal behavior, one also hears it, and two way connections between Wernicke’s area and the local and object images would be established by the memory circuit.

The higher level of neurological organization required for language does not come, therefore, from the bilateral specialization of the two hemispheres of the brain. The higher level occurs in only one hemisphere of the brain. The higher level is the higher level of behavior schemata required for linguistic manipulations of object images and the higher level of organization in the naturalistic image itself, though perhaps the addition of Wernicke’s and Broca’s area for representing such covert nonverbal linguistic behavior as verbal behavior might also be considered evidence of a higher level of organization.

The specialization of one hemisphere for language has other functions. It leaves one hemisphere of the brain unencumbered with the mechanisms required for speaking. That also makes it easier for animals to talk and do other things at the same time, even though both activities require the involvement of imagination.

Furthermore, special desires must be attached to linguistic representations in order for the desire to submit to a leader to cause member to do what is described by the leader’s verbal behavior. Thus, if those desires affected the goal selection of the linguistic hemisphere, behavioral schemata for such social behavior could evolve in that hemisphere, while behavioral schemata for satisfying other desires could continue to evolve in the other hemisphere. This requires, of course, that the linguistic hemisphere be the dominant hemisphere, for otherwise the use of language could not reliable control behavior.

There are, of course, many details about how neural connections are made in order to serve these general functions, but this evidence about the structure of the human brain is sufficient for our purposes. I have described a kind of higher level of organization in brain mechanisms that would give primates the use of a primitive language of natural sentences, and since it is within the range of random variations tried out by hominid brains, I conclude that the evolution of language using primates is inevitable. As we expect from this ontological argument, there are such mechanisms in human brains. Learning a natural language can be explained as a contained form of reproductive causation, that is, a neurological development in which linguistic behavioral schemata evolve by reinforcement selection toward maximum holist power, controlling relevant conditions in all the situations where linguistic interaction are useful at all.

Naturalistic imagination. With the evolution of the capacity to use natural sentences, subjective animal evolve a faculty of naturalistic imagination, and like each earlier stage in the evolution of imagination, it gives the animal the conception of something in the world that it could not previously think about explicitly. It is the conception of a state of affairs in the natural world, that is, the state of object in space and how they change over time. With naturalistic imagination, subjects always think about actual states of affairs against the background of what other states of affairs are possible. The possible in this case is the kind of events that can cause or be caused by the state of affairs, and so it gives them an understanding of efficient causation.

Naturalistic imagination does not replace earlier forms of imagination, but is, rather, based on them and incorporates what they understand as part of it own understanding.

Animal behavior necessarily acts on objects in space, and with the evolution of telesensory animals, there is already a conception of the object, because there is an explicit representation of the object in the sensory input system of its animal behavior guidance system. Though telesensory animals are hardwired to adapt their animal behavior to the locations of objects, those objects are not explicitly represented as being located in space.

In subjective animals, objects are represented as being located in space. Spatial imagination gives them a conception of the structure of space, and so they can think about the spatial relations of objects in terms of the effects of motion on them. This is an intuitive understanding of spatial causation. Subjective animals always see the actual spatial relations among objects against the background of the other spatial relations that are possible as a result of motion. Though geometrical structures are included in their telesensory images of objects in space, the objects in space are not explicitly represented as having geometrical structures.

In manipulative animals, objects in space are represented as having geometrical structures. Structural imagination gives them a conception of geometrical structures, and thus, they can think about the geometrical structures of objects in terms of the effects of manipulation on them. This is an intuitive understanding of structural causation. Manipulative animals always see the actual geometrical structures of objects in space against the background of the other geometrical structures that are possible as a result of manipulation. Though states of affairs are included in their representations of the world, those states of affairs are not explicitly represented as states of affairs.

In linguistic animals, the natural world is represented as having states of affairs. Naturalistic imagination gives them a conception of states of objects in space, either as events taking place or conditions that simply hold at some time, and thus, they can think about states of affairs in terms of their effects and their causes. This is an intuitive understanding of efficient causation. Though the regularities behind the most basic causal connections are built into naturalistic imagination by how it is based on spatial and structural imagination, other regularities can be internalized from experience and used in a similar way, for example, how objects are changed by fire, plants grow or can be killed, how animals behave in certain situations, and even how their own children become adults. Linguistic animals can always see the actual states of affairs against the background of the other states of affairs that are possible because of how other states of affairs might affect them or work together with them to produce effects. This is the kind of understanding that is involved in sharing a plan of social level behavior, but it can be used to explain how other states of affairs are caused or to predict the effects they will have.

Truth and logic. Natural sentences can exist as public objects, namely, as overt verbal behavior. (It is just speaking at the primitive spiritual stage of evolution, though after the advent of writing at the next spiritual stage of evolution, sentences can also exist as permanent results of overt verbal behavior.) Such public objects correspond to states of affairs in the natural world. When the states to which they correspond actually exist, the natural sentences are true, and when the states to not exist, the natural sentences are false. But this relationship of correspondence between natural sentences and states of affairs in the world is not direct. It is mediated by the faculty of naturalistic imagination.

This theory about the nature of truth for natural sentences is one of the necessary truths of ontological philosophy. It follows from the inevitability of the evolution of the linguistic level of neurological organization, because the correspondence between sentences and world is mediated by the faculty of naturalistic imagination. The verbal side of linguistic representations is connected to the nonverbal side, as we have seen, by Wernicke’s area. But that means that words acquire their references to objects or kinds of objects by way of their meanings, that is, by way of the images that they name in naturalistic imagination (of all kinds, local, object, telesensory and tactile). Naturalistic images represent states of objects in space as states of objects in space because they are constructed in naturalistic imagination by superimposing one image on another as a representation of something about objects in the local scene. That act of imagination explains how the grammatical structure of a sentence is relevant to its truth.

Logical entailments among sentences are explained by their meanings. One sentence is entailed by another just in case its naturalistic image is already constructed in the process of constructing the naturalistic image of the other. Logical connectives, such as “and,” “or,” and “not” would be introduced to make clear in verbal behavior how naturalistic images are to be combined as parts of a plan or description of the natural world. And the gradual evolution of the capacity to use a language of natural sentences would make it possible to include many predications in a single sentence (by the evolution of more versatile grammatical markers that make it possible for members to learn how to use phrases, clauses, modifiers, and the like).

“If . . .then . . “ might also evolve at this stage. But it would probably not be used to represent logical entailments between sentences, since they would be too obvious. Rather, “if . . . then . . .” would be used to represent the causal relations between states of affairs that could be understood with a faculty of naturalistic imagination. Their understanding of efficient cause relations would include not only all the basic regularities about change of location by motion and constraints on change imposed by the geometrical structures of objects in space, but also all the regularities that they have observed in the natural world, and it would be useful at time to share a mutual recognition of them. Such shared understanding of causal connections is crucial to sharing a plan of social level behavior.

Meaning and reference.This explanation of the evolution of language clarifies something about the ontological assumptions on which this philosophical argument is based. In postulating substances as causes in explaining the world ontologically, we assumed that certain aspects are constituted by the existence of substances, such as their existence and essence. This was to explain properties ontologically, without having to postulate properties as existing in addition to substances. But I did not explain how specific aspects of substances could be picked out or distinguished from one another. I simply used language to refer to those aspects and talked about them as properties of substances. The missing explanation of that ability, or at least, the foundation for it, is provided by this explanation of the evolution of language. It shows how the semantic relation is mediated by images in the faculty of naturalistic imagination.

Each word has a meaning as well as a referent, and its meaning is responsible for its reference to an object or a kind of objects in the world. Its meaning is the image that is connected to it by Wernicke’s area, and it is because that image corresponds by way of the primate faculty of imagination to an object, location, kind of object, or relation in the world that the word refers to objects, properties and relations. Likewise the meaning of a whole sentence is the naturalistic image that is connected to the natural sentence by Wernicke’s area, and it is because the naturalistic image corresponds (by way of the meanings of its constituent words and their grammatical relations in the faculty of imagination to a state of affairs in the natural world) that the natural sentence refers to such a state of affairs in the natural world.

What has been explained by ontological philosophy are the substances and aspects of substances to which words and sentences refer. Particular objects are all constituted by space and matter in some way, and particular substances fall into kinds because they have aspects of the same kinds. Those aspects of particular substances have all been explained as aspects entailed by the existence of two opposite kinds of basic substances, space and matter, and how they exist together as the objects in question. But that ontological explanation depends on being able to see that the basic substances have aspects, including their relations as parts of the same world, and how they constitute objects with the properties in question.

The reason it is possible for us to understand such an ontologically deep explanation of the world is that language acquires its relationship to the world by way of the a faculty of imagination based on the primate animal system of representation, which represents the most basic aspects of the world, its spatial and spatio-temporal structure. Spatial imagination represents the world in a way that makes it possible, in principle, to keep track of objects by their locations in space over time. The location of an object in the local image is a location in the entire world, and thus, with the evolution of language, that makes it possible to refer to any particular object unambiguously by its location in space at some time. Local images also make it possible to refer to spatial relations among objects, and how sequences of images over time represent change over time makes it possible to refer to temporal relations. The object images added by structural imagination represent the geometrical structures of objects in space, and thus, words can refer to some of the most basic properties of substances in a spatiomaterial world, along with whatever properties are represented in telesensory (and tactile, including taste) images of them. Naturalistic images constructed out of such images in naturalistic imagination can correspond to states of affairs, which are aspects of the world (that is, substances having properties). Naturalistic images with a kind of object as grammatical subject correspond to complex properties (that is, properties having properties, or aspects of aspects). But it is the meanings provided by a faculty of imagination whose very structure represents the basic, spatial nature of the world that explains what words and sentences refer to.

The gradual evolution of primitive spiritual animals.Having seen how the evolution of a primitive language of natural sentences in nomadic bands of hominids was both functional and possible, we conclude that its evolution was inevitable. It remains only to be seen what evidence there is for such a stage of evolution on earth. It is not obvious from fossils or artifacts when language first evolved, and so it will help, if we are clear about the traits we are looking for.

What makes primitive spiritual animals different from nomadic bands of hominids is the use of language to coordinate the members’ behavior in controlling conditions that affect the reproduction of the spiritual animal as a whole. Since the main relevant condition that could have be brought under control by a primitive language was acquiring free energy, coordinating behavior in hunting large animals was probably its original function. But the capacity to coordinate their behavior would have caused many other changes.

The leader’s plan for hunting behavior is only the simplest and most obvious use of language to coordinate behavior, but the capacity to share a common intention would also have changed the relations of members within spiritual animals. Nomadic bands of primates would acquire customs, but in spiritual animals, such habits and expectations would come to be mediated by the exchange of linguistic representations. Ways of behaving in certain situations would be named, and the capacity to refer to such roles would tie different practices together. Given the crucial role of the leader in guiding social level behavior, for example, there would be a special name for the member playing that role, and they might insist on customary behavior in other situations by referring to them as his instructions. Special words would evolve to describe kinship relations (though it the leader were the father of most of the children in the group, only the mother child relationship would need to be mentioned).

This is probably also the stage at which food-sharing evolved. The use of language to coordinate behavior made it possible to arrange for one group to wander around gathering vegetables while another group hunted animals, and then all meet again later at a specific location to share food. In the evolution of human beings, this division of labor was made along lines of gender. Thus, language use may have been responsible for the evolution of the unusually extreme sexual dimorphism between females and males, including perhaps the year-round sexual activity, frontal sexual intercourse, and the emotionally revealing facial expressions that transformed mating into a tighter social bond.

What is required to have the power of spiritual animals was not that a plan be distributed by the leader, but that everyone somehow share the same plan for social level behavior. That is the essence of the spiritual animal, for it includes both the social and the cultural aspect. And though it could also be accomplished without formal instructions from a leader, it is language that ties those two aspects together.

The combination of a verbal and nonverbal side in linguistic representations it what ties them together, for the verbal side is responsible for the social aspect and the nonverbal side is responsible for the cultural aspect. Since the nonverbal side consists of naturalistic images in the faculty of imagination, it is private. But the verbal side can be generated overtly, and its status as a public, observable object makes it possible for linguistic representations to serve as a structural cause for coordinating the members’ behavior. Without public linguistic interactions, it would not be possible to distribute a plan of social level behavior. The social aspect of the spiritual animal is the continual linguistic interactions among its members.

What enables linguistic interactions to provide a structural cause for social level behavior is that they are representations which can correspond to the world. The verbal side of linguistic representations is just a re-representation of representations in naturalistic imagination, for their function is to control the construction of naturalistic images in the listeners’ faculties of imagination. This public control of the images formed in imagination can induce in each brain a representation of the same state of affairs in the world. Each brain has object images for the same members and other objects in the local scene, and each brain combines them in the same way so that each corresponds to the same social level behavior of the whole. And this shared plan can coordinate their behavior, as we have seen, because each member recognizes a different one of the object images representing members as his own body and understands that the behavior predicated of it is how he must behave. This unique part-whole relationship is crucial, for it is essential to its function as a structural cause that each member of the spiritual animal see itself as a different part of the whole plan. But otherwise, the exchange of linguistic representations causes each brain to contain the same kind of nonverbal representation of their social level behavior as taking place in the same natural world. That is the cultural aspect of the spiritual animal. And since all such linguistic representations are (potentially) complete in each brain, the cultural aspect is as much a structure of the spiritual animal as a whole as the social aspect.

Evidence of such primitive spiritual animals (stage 8) depends on being able to distinguish them from nomadic bands of hominids, which are part of the radiation of primates (stage 7). There is good evidence that primates radiated into the grasslands around their arboreal homes in Africa 5 or even 10 million years ago, when large regions of forests were replaced by grasslands as the climate changed.

Bipedalism, the defining trait of hominids, is evident in the earliest fossil, know as “Lucy”, which dates back about 3.5 million years. With a brain the size of a gorilla, but a smaller body, she represents a species called Australopithecus afarensis. Apparently, there were also several other forms of Australopithecus at the time, such as africanus, robustus, and boisei, all of which were extinct by about 1.3 million years ago. (See Fisher, 1988.)

The greater facility at tool use that we expect to evolve in primates carrying clubs is evident in Homo habilis, which showed up about two million years ago. Habilis was still quite small, about three feet, the size of Australopithecus afarensis (judging by a fossil from 1.8 million years ago that was discovered in 1986). But Habilis is distinguished by evidence of greater use of stone tools. Whereas Australopithecus cracked pebbles, presumably to use as cutters and scrapers, Homo habilis made bi-facial stone tools (Acheulian culture), which could have been used for hunting animals. Some refinement of the primate structural imagination may have enabled them to use stones more effectively. Or perhaps it was the evolution of an opposable thumb.

There are two candidates for primitive spiritual animals in the archeological record, Homo erectus and archaic humans (such as Neanderthal Man, or Homo sapiens). Homo erectus evolved some 1.6 million years ago, about the time that Homo habilis became extinct (dated by fossils at 1.8 million years ago). But Homo erectus had become extinct by 250,000 years ago, about the time archaic humans evolved. It was Neanderthal Man, a species of archaic humans, that Cro Magnon Man replaced in Europe 35,000 years ago, not Homo erectus. It is agreed on all sides that Cro Magnon Man is our own species, and since that is, as we shall see, a later stage in the evolution of spiritual animals, the question is, Which species, Homo erectus or archaic humans, were the first spiritual animals (stage 8)?

Homo erectus had larger bodies than Homo habilis, within the modern body-height range, and their skulls indicate a relatively greater increase in brain size (1000cc on average, compared to about 500cc for Habilis).

There are two reasons for thinking that their larger brains gave Homo erectus the use of a primitive language.

First, Homo habilis became extinct about the time Homo erectus evolved, and the inherently greater power of spiritual animals would explain why nomadic bands of hominids became extinct.

Second, Homo erectus were the first species of this lineage to leave Africa and invade territories ranging from Europe to the Far East. This could be explained by the evolution of the use of natural sentences, because the increased capacity to coordinate behavior in hunting would have enabled them to acquire energy from larger animals, and that could have been what opened up those new habitats to them.

On the other hand, these facts can also be explained on the assumption that Homo erectus was just a late phase in the evolution of animal societies of hominids. We have seen that societies of non-primate animals can evolve instincts for more complex forms of social coordination using animal cries as signals, such as the wild dogs of Africa that are supposed to prey on ungulates by herding them into ambushes. Such an increase in their power to acquire free energy would explain both the extinction of Homo habilis in Africa and the ability of Homo erectus to migrate out of Africa. More sophisticated signs also explains two other facts that would be surprising, if Homo erectus could speak.

First, it would explain why there is no great change in their technology. The use of natural sentences should greatly improve their technology, because it would enable individuals to share their understanding of causal connections and accumulate culture based on tools. However, Homo erectus still used bi-facial stone tools, like Homo habilis. Even if they needed to control fire with them in order to invade colder climates, that is something that could be accomplished by simply carrying small fires with them.

Their lack of language would also explain why there is no evidence in Homo erectus of the changes in the larynx that seem to be required to generate the highly modulated types of sounds required for speech.

In archaic humans, such as Neanderthal Man, by contrast, the fossils and tools that remain indicate both kinds of changes, technological and physiological, as well as the fate of Homo erectus.

First, flint tools and hafted stones indicate that archaic humans had a more advanced (Mousterian) culture, as we would expect of animals with a greater understanding of causal connections.

There is also fossil evidence of changes in the larynx that suggest a much increased reliance on highly modulated sounds.

Moreover, if archaic humans did have a primitive language of natural sentences, their capacity to coordinate behavior could explain why Homo erectus became extinct about the time that Neanderthal Man and other species of archaic humans showed up. That is, Homo erectus were the societies of hominids on which archaic humans preyed, before they took up war against one another.

It seems likely, therefore, that Neanderthal Man (that is, archaic humans, or Homo sapiens) represents the primitive spiritual stage of evolution in the history of evolution on Earth.

9 Reflective stage (Rational spiritual animals).The primitive spiritual animal, as we have seen, is the new kind of animal that is possible only at the social level of biological organization. The behavior guidance system for its social level behavior is language. But it is just a primitive language of natural sentences, and there is another inevitable stage in the evolution of spiritual animals. There is a higher level of neurological organization that is both functional and possible, whose nature is evident in the grammatical structure of psychological sentences, the new kind of linguistic representations used at the reflective stage. Its function is easily understood by us, for we can reflect on how we use psychological sentences. But there is room to doubt the inevitability of the reflective stage. It may not seem possible in the relevant sense, for it is not obvious why the use of psychological sentences would evolve in the first place.

The nature of the higher level of neurological organization is evident in the difference between the grammar of natural sentences and the grammar of the new psychological sentences. Natural sentences have a simple grammar of subject and predicate (though many predications can occur in a single natural sentence). The grammatical subject of psychological sentences is restricted to subjective animals, a certain kind of object in space, and its predicate includes a verb of propositional attitude together with the name of the proposition (such as a naturalistic image) to which the attitude is taken. Such verbs of propositional attitude include “perceive,” “believe,” “imagine,” desire,” and “intend,” and what follows the verb is a word or sentence indicating the proposition toward which is the attitude is taken (that is, what is perceived, believed, etc.).

What shows that psychological sentences are on a higher level of neurological organization is not simply that natural sentences can be parts of them. Natural sentences may already be parts of natural sentences, for example, as phrases, clauses, and even modifiers as well as compound natural sentence (formed by conjunction). Psychological sentences indicate a higher level of organization because the natural sentences included in them are parts of a new kind of grammatical structure, which represents the proposition (that is, the meaning of the embedded sentence) as playing a certain role in causing the subject’s behavior or beliefs.

Psychological states are what is represented by the predicates of psychological sentences, and so psychological sentences represent objects as having psychological states, that is, as subjects. This is something beyond what natural sentences can do, for they represent only naturalistic states, or states of objects in space (such as objects having relations in space, objects having geometrical or other properties, and the like). (Thus, although natural sentences can describe spoken words and sentences as public objects, that is, as verbal behavior, they cannot represent them as words and sentences.)

The function of psychological sentences is to represent the causal roles that linguistic representations play in the processes of guiding the behavior of an animal subject, as a way of explaining the subject’s behavior (or beliefs). Beings like us can understand how the use of psychological sentences facilitates such explanations, because we can reflect on how we use them, for example, to “see into the minds” of other subjects.

By reflecting on how we know about other subjects, we know that we can often explain the causes of their behavior by putting ourselves in the other’s position and imagining what we would do. We take the beliefs and desires that would lead us to behave the same way as explaining the other’s behavior. Thus, when we know something about how others behave, we can generally figure out what desire is moving them and what their intentions are, for we can assume that they have beliefs about the world are generally held and believe whatever perception tells them about their particular situation. We see into their minds by inferring to the sets of beliefs and desires that best explains their behavior.

Psychological sentence also makes the users reflective, for they can be used to explain their own behavior (or beliefs). Though psychological states are just causes of the behavior (and beliefs) at work in the animal behavior guidance system, the capacity of the subject to reflect on those causes evolves into an important part of the very process by which they case behavior (or beliefs), and that earns them the special name, “reasons.” Reasons are causes that are represented as causes as part of their process of causing.

More generally, to be able to use psychological sentences is to have a faculty of “rational imagination.” It is a form of imagination, like those that have preceded it, except that it gives the user the ability to understand “rational causation.” They can see reasons as causes in other subjects, in themselves, or in general, that is, as arguments about what to do or what to believe. Thus, reflection makes the linguistic subject rational.

The most spectacular accomplishments of the reflective stage come from how the exchange arguments constitutes another form of reproductive causation, which is responsible for cultural evolution. Cultural evolution is another example of the reproductive global regularity we have called “gradual evolution.”

Though cultural evolution is contained within the spiritual animal, it works in basically the same way as biological evolution, that is, by how reproductive cycles of arguments add up in the space provided by a spiritual animal as time passes.

Since the use of psychological sentences includes the capacity to construct linguistic representations in which a conclusion comes together with reasons for it attached, it is possible to engage in a new kind of linguistic interaction: arguing. The exchange of arguments, as we shall see, gives rise to a new form of evolution by reproductive causation: cultural evolution. With the same kind of ontological cause as gradual biological evolution, the same kind of ontological effect follows, namely, the gradual evolution of culture toward natural perfection for reproducing organisms of its kind, that is, the natural perfection of arguments, which is to know the good, the true and the beautiful.

Cultural evolution is such an important part of the gradual change that takes place at the reflective stage that this section is divided into to main subsections: biological evolution and cultural evolution.

Biological evolution will show that the evolution of the reflective level of neurological organization is inevitable, by showing not only that it opens up a new range of powers to control relevant conditions, but also that it will eventually be tried out as a random variation in circumstances in which it is functional, so that is naturally selected.

Cultural evolution will show that cultural evolution is a form of reproductive causation that is contained in rational spiritual animals (by showing how arguments are “organisms” that impose natural selection on themselves by going through reproductive cycles). It will also show that, even under the most favorable conditions, gradual evolution of culture at the rational spiritual stage leads to a natural perfection for arguments of its kind that includes certain dichotomies that limit the power of reason to control relevant conditions.

Biological evolution of the reflective level.Primitive spiritual animals are a form of life, by our definition, because they are products of reproductive causation with the autonomous activity of going through reproductive cycles on their own. And as a form of life, they make themselves evolve by imposing natural selection on themselves. But the linguistic stage is merely the first stage in the gradual evolution of spiritual animals. It merely prepares the way for the reflective stage.

The reflective stage of evolution is the ninth stage, by our reckoning, in the series of stages leading up to beings like us. The organism that evolves at the ninth stage is the rational spiritual animal. The use of a primitive language, the behavior guidance system that accounts for the origin of spiritual animals at the previous stage, is transformed into a more powerful behavior guidance system, called “reason.” Indeed, reason is so good at controlling relevant conditions that it takes over the function of guiding all behavior, at the individual as well as the social level.

What makes reason the source of such great power powerful is that rational spiritual animals constitute a new form of reproductive causation, in which the arguments accumulated as culture evolve gradually in the direction of natural perfection for “organisms” of their kind. Since that includes knowing what is good, cultural evolution makes reason increasingly powerful.

It is cultural evolution during the reflective stage that leads to another stage of evolution, (stage 10, the philosophical stage), not biological evolution. The philosophical level of neurological organization does not require any genetic changes (that is, changes supplied by the mechanism of embryological development, the multicellular biological behavior guidance system).

Revolutionary changes in evolution are, however, a reproductive global regularity. Like all previous evolutionary stages, the reflective stage is caused by a higher level of part-whole complexity about the reproducing organisms. It is a higher level of neurological organization in the series we are following.

The direction of evolution at every stage is natural perfection, or maximum holistic power, and the gradual evolution of primitive spiritual animals prepares the way for rational spiritual animals. When gradual evolution makes the nervous structures involved in using natural sentences reliable enough, it is possible for them to serve as parts of a larger structure in the nervous system, for using psychological sentences.

But the next stage is inevitable, according to reproductive causation, only if it is both functional and possible. Its functionality depends on the higher level of organization opening up a whole new range of powers that can evolve gradually over a long period as a result of the natural selection that they impose on themselves. And its possibility depends on whether the higher level of neurological organization can be tried out as a radical random variation on the structures of the organisms that are evolving at the previous stage.

The function of the reflective level of neurological organization is not very problematic, because it is exhibited so clearly in the grammatical structure of psychological sentences and the way in which they are used. But its possibility is less obvious.

Given the capacity of the mechanism of embryological development to try out random variations, the higher level of neurological organization itself is hardly an obstacle to the evolution of reason. But if the power of the reflective level comes mainly from the cultural evolution of arguments it constitutes, it may be hard to see how reason could evolve by the natural selection of a radical random variation on linguistic brains.

There is, however, something that that makes the evolution the reflective level is inevitable. As we shall see after considering more carefully the nature and function of the reflective level of neurological organization, an urgent need arises late in the linguistic stage of evolution that makes even a very simple and weak form of reflection crucial to controlling conditions that affect reproduction.

Function of the reflective level of neurological organization. The nature of the reflective level of neurological organization that causes the reflective stage of evolution is indicated by the grammar of the new kind of sentences that are used at this stage. But behind that linguistic structure, making the use of psychological sentences possible, is a new form of imagination: rational imagination. And like each of the previous evolutionary stages, the new kind of understanding that rational imagination affords is the source of the new powers that are acquired in the long period of gradual evolution at the reflective stage.

Psychological sentences. Psychological sentences, like natural sentences, have a simple subject-predicate grammar. But their grammatical subject refers only to subjective animals (or objects assumed to be like them), and the predicate is not of the kind found in natural sentences. Its meaning cannot be explained by simple predication.

The psychological predicate is made up of a verb of propositional attitude and the name of a proposition (a natural or psychological sentence) to which the attitude is taken.

Verbs of propositional attitude represent the causal roles that propositions play in guiding animal behavior. The propositional attitudes include perceiving, believing, remembering, imagining, desiring, and intending. But the kinds of verbs of propositional attitude fall into two basic groups, beliefs and desires, depending on whether the attitudes have to do with input to the behavior guidance system or selecting and generating its output.

Psychological predicates represent what are called “psychological states.” Thus, psychological sentences predicate psychological states of certain kinds of objects in space. The kinds of objects that have psychological states are animals with at least a subjective animal behavior guidance system (or objects thought to be like them), and thus, psychological sentences represent objects in space as subjects.

The psychological states picked out by psychological sentence are states that play causal roles in determining behavior and beliefs. They are causally relevant states of the subjective animal behavior guidance system.

Beliefs and desires combine, as we have seen, to give animal subjects intentions, which generate their bodily behavior. Desires determine the goals, and beliefs determine the means.

But beliefs also have causes in the animal behavior guidance system, for they can be caused by perceptions. The causal roles that perceptions play in determining beliefs can be as complex as those involved in determining behavior. Besides giving the subject beliefs about currently perceived objects, current perceptions can combine with already formed beliefs to change beliefs about currently unperceived objects. And perceptual reports made by others can have a similar effect.

The meanings of psychological sentences derive, therefore, from their use in explaining and predicting behavior (or beliefs). But in order to be used in that way, the speaker and listener must both have a faculty of imagination by which to understand explanations of behavior and beliefs.

Just as understanding the structure of space depends on spatial imagination, understanding structural causes depends on structural imagination, and understanding natural sentences depends on naturalistic imagination, understanding psychological sentence depends on a form of imagination. It will be called “rational imagination” (though it might just as well be called “psychological imagination,” “subjectivistic imagination” or even “reflective imagination”).

As the function of psychological sentences suggests, that new faculty of imagination is basically the subject’s own animal behavior guidance system. That is, the ability to think about psychological states as causes of behavior (or beliefs) in another subject, for example, comes from using one’s own brain to simulate the behavior guiding process in the other’s brain. To use a psychological sentence to represent the psychological state of another subject is to temporarily impose that psychological state on one’s own brain as an act of imagination while thinking of it as belonging to the other. The further changes it causes in one’s own brain state are then seen as happening in the other subject.

The grammar of psychological sentences is, therefore, and indication of a higher level of neurological organization in the faculty of imagination. The meaning of a natural sentence embedded in a psychological predicate is not merely conjoined with other predications as part of a complex naturalistic image. (Nor is it a disguised form of predication, like a clause or phrase.) Instead, the verb of propositional attitude represents the naturalistic image (or proposition) as playing some role in a behavior guiding process. The ability to use psychological sentences requires, therefore, a brain mechanism that handles natural propositions in a new way, one that is based on its already being a representation and that represents it as having a further role in guiding behavior.

Since the psychological sentence represents a new way of handling the meanings of whole sentences in the faculty of imagination, it can handle the meanings of psychological sentences in the same way. Thus, subjects can have beliefs and desires about the psychological states of subjects, such as desiring that someone love them and believing that they do not.

Rational imagination. The capacity to represent the world in some way depends on having a system that can represent what is actual against the background of what is possible. What is possible are changes of some kind that can occur as an effect or as a cause of what is supposed to be actual. The capacity to see the possible is provided, as we have seen, by the faculty of imagination, which evolves by stages in the animal behavior guidance system.

Form of imagination. In telesensory animals, the object is represented as a object of a certain kind only because it can also recognize objects of other kinds. But since the other possible kind of objects are not represented by images that can be called up from memory by covert behavior, telesensory animals lack imagination altogether. And the advent of imagination makes it possible to represent objects as having other aspects than just their kinds.

The subjective animal’s spatial imagination makes it possible to represent objects as being located in space, because it gives the animal a conception of space. With spatial imagination to can call up sequences of images that represent the effects of motion, it can see actual objects against the background of how they might be different because of their motion relative to one another.

The manipulative animal’s structural imagination makes it possible to represent objects in space as having geometrical structures, because it gives the animal a conception of geometrical structure. With structural imagination to call up sequences of images representing the consequences of manipulation, it can see the actual geometrical structures of objects against the background of how they might be different by manipulation.

The linguistic animal’s naturalistic imagination makes it possible to represent objects in space as having certain states, because it gives the animal the conception of a state of affairs. With naturalistic imagination to call up sequences of images representing the regularities among states involved in causal connections, it can see naturalistic states against the background of how things might be different as a result of efficient causation.

The reflective animal’s rational imagination likewise makes it possible to represent certain kinds of objects in space, namely, subjects, as having psychological states, because it gives the reflective subject the conception of a psychological state. The capacity to represent psychological states is the capacity to see having those states against the background of what other psychological states are possible, including not only how they are different from other possible psychological state, but also now they might cause or be caused by other psychological states.

The structure of the faculty of imagination.Imagination first evolved with the subjective animal as a higher level of neurological organization than telesensory animals, and we have seen how the two succeeding animal stages of evolution were caused (at least in part) by a higher level neurological organization within the faculty of spatial imagination. A brief review will show how rational imagination is just another level of part-whole complexity in that series.

The subjective animal uses input about its current bodily condition to assemble telesensory images as a local image representing objects in the local scene from the point of view of it body, and spatial imagination is the capacity to think about spatial relations among objects by using covert locomotion to call up from memory sequences of local images that represent the effects of motion relative to objects in its territory. We have seen how systems recognizable in the anatomical structure of the mammalian brain serves all the subfunctions required for spatial imagination, and that is the framework in which all the subsequent forms of imagination evolve.

Structural imagination is the capacity to think about the geometrical structures of objects in space by using covert manipulation to call up from memory sequences of telesensory images within a (perceived or imagined) local image that represent the results of objects rotating and interacting with one another. Its higher level of neurological organization was possible because it used the same mechanism for recording images together in sequences in memory as spatial imagination, except that instead of storing multiple sequences of local images as a map of the effects of locomotion in various direction in the entire territory, multiple sequences of telesensory images of objects were stored as an object image that had to be located within a local image.

Naturalistic imagination is basically the capacity to combine images of various kinds (telesensory images as well as local and object images from spatial and structural imagination) as parts of naturalistic images, which represent states of affairs in the natural world (for example, an animal being of a certain kind or behaving in a certain way).

Images that derive from lower levels of neurological organization are the meanings of the (nonlogical and nongrammatical) words used in natural sentences. The local image gives the object a location in the world (real or imaginary) and represents spatial relations among them, whereas object images (as well as telesensory and tactile images) represent kinds of objects according to their perceptible properties, geometrical structures or dispositions. (Such meanings can be more or less complex depending on how many different sequences of images are united in them)

The effect of combining such images in naturalistic imagination is to generate a new sequence of images, or a naturalistic image, which depends on them. The combination is asymmetrical, because there is a difference between using an image as the grammatical subject of natural sentences and using it as a predicate. The naturalistic image is the meaning of the natural sentence, which represents an object as being an object of a certain kind, as being located in a certain place, or as having some other naturalistic state. Thus, by using covert linguistic manipulation to construct naturalistic images, the subject can think about states of affairs in the world, and the effects of imposing it temporarily on the memory of one’s own sensory input system (the beliefs that accumulate with one’s map of the territory) are its implications, including its role as a efficient cause or effect.

But natural sentences are representations in the linguistic system of representation, and in order to serve their social function of coordinating behavior, it must be possible to represent the covert nonverbal behavior of naturalistic imagination publicly, as overt verbal behavior, including both words indicating the images (or meanings) that pick out objects, properties or relations in the world and grammatical markers for those words indicating how those meanings had been combined in naturalistic imagination (that is, as grammatical subject, predicate, etc.). The words and grammatical markers combined in the sentence must enable another language user to construct the same naturalistic image in her own naturalistic imagination.

Rational imagination is basically the capacity to use psychological images to represent the psychological states of subjective animals. Psychological images are the meanings of psychological sentences, and just as the structure of naturalistic images is evident in natural sentences, so the structure of psychological images is evident in psychological sentences. Rational imagination requires a higher level of neurological organization than naturalistic imagination in much the same way that naturalistic imagination was higher than both spatial imagination and structural imagination (and in contrast to how structural imagination is higher than spatial imagination, as indicated in the functional diagram of the reflective animal behavior guidance system).

Psychological images are made by combining naturalistic images (or psychological images) as parts of a larger (psychological) image, which represents the causal roles that those images play in causing behavior (and beliefs) in subjective animals. Psychological images are constructed in the sensory input system by linguistic behavioral schemata in the behavioral output system, and in both systems, it requires a higher level of neurological organization. By using covert nonverbal behavior to construct the meanings of psychological sentences, one temporarily imposes the psychological states one would attribute to another subject on one’s own brain, and the effects of those temporary beliefs or desires on one’s own beliefs and desires are the conclusions that follow from them. But since this is all predicated of some subject, the psychological state and its implications are seen as occurring in some subject.

There are two basically different kinds of psychological images, beliefs and desires (or intentions), because naturalistic (and psychological) images play two basically different roles in the sensory input system and the behavioral output system. The sensory input system contains the memory map of the animals territory and all the general and particular beliefs about the world that accumulate about its objects, including, at the rational stage, beliefs about some of those objects as subjects (with psychological states). Desires are basically dispositions to behave in certain ways towards objects of certain kinds, and they are represented like intentions, by behavioral schemata (and as images in the sensory input system of other bodies behaving appropriately). Reflective linguistic acts must, therefore, be able to impose the meanings of sentences on the brain in two basically different ways.

That is the nonverbal side of the reflective linguistic act, but since psychological sentences are representations in the linguistic system of representation, they must also serve its social function of coordinating behavior. Thus, the covert nonverbal behavior in rational imagination must be represented publicly in the speaker’s overt verbal behavior so that listeners can reconstruct the psychological image in their own imaginations, calling up sequences of images of the same kinds. (See below, Structure of reflective brain.)

Understanding of rational causation. The faculty of rational imagination is a way of understanding how psychological states are causes of behavior and beliefs. The sequences of images that are called up in rational imagination as a result of constructing a psychological image represent regularities that hold of subjective animals generally, because animal behavior guidance systems all work in basically the same way, with beliefs and desires determining intentions (and perception together with background beliefs determining new beliefs). With inferences built into the structure of rational imagination, the changes that occur in one’s own beliefs or intentions as a result of constructing a psychological image in rational imagination correspond to what would happen in other brains (though the fit is more detailed the more the other subject resembles a reflective subject, with rational imagination). But since it is a psychological image, it is the representation of some object as a subject, that is, as having the psychological state (as indicated by the grammatical structure of the psychological sentence).

Rational imagination is, therefore, a way of understanding a kind of causal connections in the world. In this case, the causes have to do only with the behavior (or beliefs) of subjects, rather than the behavior of objects in space generally. Thus, just as spatial imagination affords an intuitive understanding of spatial causation, and structural imagination affords an intuitive understanding of structural causation, and naturalistic imagination affords an intuitive understanding of efficient causation, so rational imagination affords an intuitive understanding of rational causation.

Rational imagination can be used to predict the behavior of subjects in any situation. Several psychological states may have to be predicated of the subject to represent all the relevant beliefs about the situation he is in and the various desires (or longer range intentions) that are at work in him. They are all held together as parts of the psychological image. And they are all imposed at once as a temporary modification on one’s own worldview and goals, as if one were in the other’s situation. But they are parts of a psychological image, and so they are seen as states of the other subject. The changes that occur in one’s beliefs or intentions are the predictions one makes about the other subject, given those premises. The conclusions may be just inferences about what the subject would come to believe. But when it leads to new intentions, it is a prediction of the subject’s behavior.

But the understanding of rational causation can be used in other ways. When the other subject’s overt behavior is what is known, rational imagination can be used to infer the intention or motivating desire. Along with common background beliefs, the other subject is assumed to have whatever additional, relevant beliefs that come from where he is located. In order to discover his intentions, it is only necessary to compare possible sets of desires and beliefs and the intentions to which they would lead, for it is basically an inference to the best rational explanation of the behavior that is observed. Thus, one can “see into the other subject’s mind.”

Since psychological sentences can be used to understand one’s own beliefs and desires, as well as others, evolution at this stage leads to the ability to represent the causes of one’s own behavior, as causes of behavior, as part of the very process of causing the behavior. This means that subjective animals with the use of psychological sentences are reflective subjects.

It is not merely that reflective subjects monitor the desires and beliefs that are causing their behavior. More than that, as we shall see, the desire to submit to a leader’s instructions evolves into the desire to submit to reason, and thus, reflective subjects can do what they discover in rational imagination to be the best course of action, all things considered, even when it is opposed by strong, immediate desires to the contrary. That is the “autonomy of reason.”

This transformation of the causes of behavior in reflective subjects has given those causes a special name in ordinary language: “reasons.” Thus, reasons are causes. But they are causes of a special kind, because they depend on being represented as causes in order to be effective as causes of behavior (or beliefs) at all. That makes reflective subjects enormously powerful, for as we shall see, not only does it enable them to control the conditions that affect their reproduction, but to control other conditions that they see as good. It is an indication of the autonomy of reason.

From telesensory animals on, the animal behavior guidance system has had a conception of the object, and we have seen how it is enriched by stages with the conception of their locations in space, their geometrical structures, and their naturalistic states. That might be described as the evolution of the the “concept of the object.” But with the advent of rational imagination, the subject has the conception of the subject, that is, of objects as having psychological states. Since that is based on an way of understanding psychological states as causes or effects, that is, as reasons for the conclusions drawn by their animal behavior guidance systems, it means that a whole new world of facts opens up to reflective subjects. Reflective subjects can see into one another’s minds, and that begins an evolutionary stage in which they become increasingly powerful in controlling all the conditions that affect their reproduction, not only conditions in the natural world, but also conditions in a world of subjects who can all see into one another’s minds.

The possibility of the reflective level of neurological organization. Having seen how a higher level of neurological organization could open up an entire range of new powers to control relevant conditions, we can conclude that its evolution is inevitable, if it is possible, in the sense that it can be tried out as a random variation and naturally selected for such a function. There is not much reason to doubt its possibility when it comes to the capacity of the mechanism of embryological development to try setting up brains with reflective imagination, because the reflective level occurs in the faculty of imagination. But at first, the reflective level of neurological organization would be much simpler and weaker than the capacity for reason we have been considering, since the brain mechanisms on which beings like us can reflect on are informed by many centuries of cultural evolution. Thus, it may not be obvious how, even if a higher level of neurological organization were tried out as a random variation, it would be naturally selected. But before we take up that problem, let us make sure that the reflective level of neurological organization is as simple as it seems to be.

Structure of the reflective brain. The functional diagram of the reflecting animal behavior guidance system shows how nervous systems of the kind we have been considering could incorporate a mechanism for rational imagination. Since the higher level of neurological organization occurs within the faculty of naturalistic imagination, it occurs in each of the systems involved in generating verbal behavior in mere linguistic animals. The psychological linguistic act and psychological image are represented as more encompassing forms of behavior than naturalistic acts and images, because the latter are contained as special parts of the former.

Speaking. In the speaker, the psychological linguistic schema must not only construct all the images of psychological states (beliefs and desires, including both the proposition and the propositional attitude toward it in each case), but also predicate the psychological states of an animal subject. In order to express this nonverbal activity in the rational imagination verbally, a more complex grammatical structure is required. The sentence must identify the naturalistic image (or psychological image) whose causal role is being described, it must identify the kind of causal role predicated of it, and it must identify the subject in whom such a psychological state occurs. Since there is already one predication in any naturalistic image toward which the propositional attitude is taken, a basically new kind of grammatical marker is required to indicate the kind of predication that occurs in constructing psychological images. Those grammatical markers are the verbs of propositional attitude.

Verbs of propositional attitude indicate a kind of predication in which a naturalistic (or psychological) image is represented as playing certain kinds of causal roles in causing behavior (or beliefs). That is, psychological linguistic schemata must be able to construct naturalistic (or other psychological) images in the sensory input system and then temporarily impose them on the speakers brain so that their effects on the brain can represent their implications about intentions (or beliefs). The verbs of propositional attitude represent how they are imposed on the brain, and given the nature of animal behavior guidance systems, there are three basically different causal roles they might have.

Verbs of propositional attitude such as “believe,” “perceive,” and “remember” indicate various ways of imposing naturalistic (or psychological) images on the sensory input system. They constrain the speaker’s behavior guiding processes so that the sequences of images that are called up from memory in rational imagination represent what a subject would infer in certain situations.

Verbs of propositional attitude such as “desires,” “needs,” and “wants” indicate the imposition of naturalistic (psychological) images on the goal direction system of the speaker’s brain. They constrain the speaker’s brain so that the sequences of images that are called up from memory represent what a subject would try to do when certain kinds of behavioral schemata were activated (relative to certain objects).

Verbs of propositional attitude representing intentions indicate the imposition of naturalistic (or psychological) images on the speaker’s behavioral output system. They constrain the speaker’s brain so that the sequences of images that are called up in rational imagination represent the beliefs or desires that might lead a subject to behave with such an intention.

Though there are three basically different kinds of causal roles that such first level propositions might play in behavior guidance processes, the reflective linguistic schemata need only two basically different ways of imposing propositions on the brain, because desires and intentions are both represented in the behavioral output system.

The goal selection system does not represent goals on its own, but only by activating certain kinds of behavioral schemata in the behavioral output system (perhaps, relative to certain objects in the sensory input system). Thus, desires can be represented in rational imagination by imposing propositions on the behavioral output system, for if the kinds of behavior represented are general enough in the situation, the sequences of images called up from memory will be inferences about how to behave in that way (perhaps relative to so object picked out in the sensory input system)

Since there are only two basically different verbs of propositional attitude, no great changes are required of biological evolution in order for linguistic brains to acquire the ability to use psychological sentences. It would be enough for some random variation to try out a mechanism for imposing propositions (naturalistic or psychological images) on the speakers brain in two different ways, one affecting mainly the sensory input system and the other affecting mainly the behavioral output system. The distinctions among kinds of psychological states is each class could then be acquired by learning.

For example, the difference between imposing a naturalistic image as a perception or imposing it as a belief could be acquired as part of the process of learning to impose propositions on the sensory input system, for the difference would show up mainly in the strength of the belief and how easily it could be discounted.

Likewise, the difference between imposing a proposition as a desire and imposing it as an intention could be acquired as a refinement of the capacity to impose propositions on the behavioral output system, for it would merely indicate which of the sequences of images that were called up from memory in rational imagination is relevant, those representing inferences about how to behave (that is, its consequences) and those representing inferences about the beliefs and desires that motivate it (or its causes).

In order for verbal behavior to indicate the activity in the speaker’s rational imagination, the nonverbal covert side of the linguistic act must be expressed verbally, and the job of representing the activity in rational imagination in verbal behavior is performed by Wernicke’s and Broca’s areas as indicated in the functional diagram of the reflective brain. (The projection from the former to the latter is not represented in this functional diagram, but it can be seen in (See the diagram of the linguistic brain in the Linguistic stage, Stage 8.)

The motor output for speaking comes from Broca’s area. But Broca’s area depends on input from Wernicke’s area, because Wernicke’s area is what receives information from rational imagination about how the psychological image is being constructed.

Wernicke’s area must not only give the names of the images (meanings of words) involved, but also have grammatical markers that distinguish one kind of predication from another (that is, the naturalistic predication that may occur in the embedded naturalistic sentence from the predication of the psychological state to some subject). That is the role of verbs of propositional attitude: they are the grammatical markers for the new kind of predication, the one that is involved in imagining subjects as having psychological states.

Since grammatical markers for the predication involved in the construction of naturalistic images has already evolved, they can be embedded in the psychological sentence after the verb of propositional attitude. That is, the naturalistic sentence is contained in the psychological sentence after the verb of propositional attitude, like a name for the naturalistic image toward which the attitude is taken.

With the capacity to distinguish psychological from naturalistic predication, it is possible to treat psychological images in the same way as naturalistic images in rational imagination. Thus, subjects can be seen as having beliefs or desires about beliefs or desires.

Assuming that Wernicke’s area supplies the required words and grammatical markers, Broca’s area can generate the motor commands for the words and the grammatical markers through the motor neocortex. Once again, verbal behavior would be generated by the linguistic schema only indirectly, as a result of thinking the content of the sentence and the effect of the images constructed in imagination on Broca’s area. (See Linguistic stage: Possibility: Structure for details.

Though only the verbal side of linguistic behavior is overt, it can also be generated covertly. That is, one can speak to oneself silently by generating the motor commands for speaking covertly. But it is also possible to carry out the nonverbal side of a linguistic act without generating even covert verbal behavior. That is how the reflective subject normally thinks.

Listening. The listener’s understanding of psychological sentences parallels that of natural sentences. Wernicke’s area constructs the psychological image in the listener’s rational imagination using telesensory input about the speaker’s overt verbal behavior.

Wernicke’s area acquires the nervous mechanisms for decoding verbal behavior in the development of the capacity to speak psychological sentences. The connections between words and the images that are their meanings and between grammatical markers and the ways of combining images that are their meanings are two-way connections (as indicated in the functional diagram). That is, Wernicke’s area uses the words identified in telesensory input to call up the images and the grammatical markers identified in telesensory input to combine them on the inferior parietal role in the same way that the posterior cingulate neocortex would have, if the brain had been speaking the sentence meaningfully. Thus, the listener can grasp the meaning of the sentence heard. Broca’s area is not required for comprehension.

Unlike the previous levels of neurological organization, I cannot point to any additional brain structures that realize the higher level of neurological organization. Its existence is basically an inference from the structure of psychological sentences and their function as a faculty of rational imagination. But given the basic structure of the faculty of imagination, it is plausible, at least, to suppose that there is some new brain structures that enables the reflective brain to impose propositions on the brain in the two basically different ways described above.

Wernicke’s and Broca’s areas of the neocortex are properly evidence of reflective level neurological mechanisms. I cited them as evidence for the evolution of the mechanisms required for the use of natural sentence, but that is just an inference. There are no brains left from the primitive spiritual stage of evolution to show that these brain mechanisms evolved first in linguistic brains. Even if there were, there might be no dramatic evidence of the difference between these two levels of neurological organization, because the reflective level of part-whole complexity does not require any basically new systems. It requires only higher levels of part-whole complexity in the same systems that constitute naturalistic imagination with its capacity to generate and be controlled by over verbal behavior.

There may, however, be some evidence for this theory about the difference between beliefs and desires in the way different kinds of words are processed in Wernicke’s area. Different regions of neocortex in Wernicke’s area are the locus for words referring to objects in space, such as kinds of animals, and words referring to kinds of behavior, including tools. It suggest that there is a connection between telesensory images of each kind of behavior and behavioral schemata for generating that kind of behavior. This is evidence of a mechanism by which the brain distinguishes between beliefs and desires, that is, between psychological states most relevant to input and those most relevant to output.

There is little danger in proceeding at this point on the assumption that there is a reflective level of neurological organization that can be tried out as a random variation. Given the structure of the faculty of imagination, only rather modest changes are required for the behavior generator to speak psychological sentences and, once again, the details of the nervous mechanism can be acquired by learning.

The origin of the reflective level of neurological organization. The only reason to doubt that the reflective state of evolution is inevitable have to do with its origin, that is, how a simple and weak form of rational imagination tried out as a random variation on linguistic brains could make reflective brains powerful enough to control some new condition for which they would be natural selected.

There was, however, an original function for the reflective level of neurological organization. It comes from a uniquely demanding form of natural selection that primitive spiritual animals eventually imposed on themselves. They waged war on one another. The advent of war meant spiritual animals had to make a new kind of choice between incompatible kinds of behavior. That choice could not be made very reliably with naturalistic imagination. But it could be made much more reliably with rational imagination, even if it were not very reliable and occurred only in the leader of the group. Thus, since the capacity to use psychological sentences was a possible random variation on linguistic brains, it was tried out, and it was quickly selected for controlling an urgent new condition affecting their reproduction. That began a stage of evolution that made the members reflective subjects and eventually gave them the enormous power of reason.

The advent of war. Since the use of natural sentences originally evolved to coordinate individual behavior mainly in hunting animals, it is not surprising that primitive spiritual animals would eventually use it to control the outcome of their interactions with other groups of non-linguistic hominids. The new sources of free energy opened up by the use of natural sentences would eventually be exhausted, because there is only a finite amount of free energy they can use in any region and their reproduction would multiply the number of spiritual animals consuming it. Like all reproducing organisms, spiritual animals would eventually impose natural selection on themselves. But spiritual animals had a new way of overcoming scarcity. They could turn their hunting skills on nomadic bands of hominids, either simply killing them so that they could take over the supply of usable energy in the territory or, perhaps, even preying on them, that is, consuming them for the energy such living organisms contain.

The use of language was the origin of war, because such behavior could not evolve before the use of natural sentences.

War could not be tried out as a random variation by their biological behavior guidance systems. Membership in hominid societies was, like other animal societies, rather fluid. Some exchange of members was normal, if only as an adaptation of the instinct of young primates to mate outside the group in which they are born. When necessary, nomadic hominid bands could accept new members, combine with one other to form new groups, or redistribute members, and fights between single hominids (or between leaders of coalitions) would determine a dominance hierarchy within any animal society. Thus, when resources were scarce and nomadic bands of hominids encountered one another, there might have been fights among individuals, or even among coalitions, but no group would systematically kill off all the members of the other group. Dominance battles do not usually end in death, and since social level behavior was still instinctive, the evolution of violent behavior toward all the members of another group would require the same random variation to occur simultaneously in nearly all the members of some group. Only if they all happened to have the new desire to kill all the members of another group (or to follow their leader in doing so), this social level trait would never be tried out and, thus, never selected. Such a combination of random variations is so unlikely as to be impossible, especially if hominids had the normal inhibition about using other members of their own (or kindred) species as a source of free energy.

No such improbable random variation is required, however, to explain how spiritual animals could behave in such a violent way toward groups of non-linguistic hominids. No changes in their desires would be necessary, because the desire to submit to their leader inclined every member to do his part in the group plan pronounced by the leader. Since the use of a primitive language would enable them all to see how their joint behavior would work together in bringing about a goal they all desired, they could act with the same intention. They had practice in the use of language to coordinate violent behavior from hunting other kinds of animals. They may have felt some reluctance to take such actions against a kindred species, but it could be overcome, at least in times of scarcity, by their disposition to submit to a leader and cooperate in social level behavior, especially if they were starving and the desire for food was intense. Even if they could not bring themselves to eat hominid bodies, they would be motivated by seeing how a plan of attack that killed all the members of the other group would give them access to what food there was in the region.

The use of natural sentences, therefore, made war against groups of hominids inevitable. Though war derived from hunting, it was basically different, because members of hominid bands were disposed to protect one another. They would fight back as best they could, when they had no other option (because as we have seen, individuals on their own were still usually doomed by predatory beasts, such as lions and packs of wolves). But even with the use of tools to fight back, hominids were no match for spiritual animals. They had no defense against attack by a spiritual animal that could adapt the spatial aspects of its social level animal behavior to spatial aspects of the situation in imagination prior to acting. Hominids could be surprised and trapped by the spiritual animal’s capacity to impose a geometrical structure on the motion and interaction of objects in space. (After all, warfare is just a special case of controlling the thermodynamic flow of free energy toward evenly distributed heat in the region). Nomadic hominids may sometimes have chosen to run away from their attackers, but even if they survived predation by other animals, that still deprived them of access to the food available by hunting in the region.

The new behavior of spiritual animals was not merely ritualized fighting of the kind that evolves within a species to divide up limited sources of energy in a region. They killed all the members of other hominid groups in order to take over their territory. It was inevitable, when their own reproduction made resources scarce, because war was a new way of controlling this most basic condition affecting their reproduction and it was possible for them. In the end, therefore, their new means of acquiring energy meant the extinction of non-linguistic hominids.

This kind of behavior was not long reserved, however, for use against mere hominid societies. Adapting to warfare gave linguistic animals aggressive desires, like anger and hatred, that made it easy for them to kill animals like themselves. Thus, once all the non-linguistic hominid societies in their region had been wiped out, spiritual animals had enough experience with violence against other groups that, when their own continuing population growth once again made resources scarce enough, some spiritual animals, at least, would try the same means against other spiritual animals. It may eventually have involved yet further changes in the desires they felt towards other members of their own species. But it would not require all the members to try out simultaneously the same random variation, because a leader with a suitable random variation could motivate his followers. Since war again other spiritual animals was a possible means of controlling a relevant condition, reproductive causation inevitably made it actual. That is simply how reproductive cycles of spiritual animals add up in space over time.

War against other spiritual animals was not just predation, for it would usually result in death for all the members of the other group (except possibly some women who were kept alive for other purposes). That was the only safe way for spiritual animals to protect themselves from members of other spiritual animals who were accustomed to cooperating in violent behavior. But there is no reason to rule out cannibalism (if that term applies in this case), because eating the victims of their killing was a possible source of food. Predation was not, however, the original function of war even against non-linguistic hominids. War supplied much more food all at once than could be consumed, and the risks of battle made it more costly than hunting other animals. Furthermore, spiritual animals would have engaged in war, even if they did not eat their victims, since it had the effect of removing competitors for the energy available in the region.

The need for a better behavior guidance system. Though war was inevitable, it was a fateful juncture in evolution. It changed radically the world in which spiritual animals lived. The environment posed a new kind of danger for spiritual animals, and they had to make a new kind of choice between fundamentally different kinds of behavior. Every time they encountered a society of language-using animals like themselves, spiritual animals were forced to choose between war and peace. It was a crucial decision, for if they chose to be friendly toward a group that was planning to kill them, they could all die. But if they chose to war against a society that was willing to be peaceful, they would suffer the losses that such activities involve. Even if they won, the costs would be unnecessary, if resources were not scarce. They could, of course, choose to move out of the way, but that alternative would often mean going without food as others took over the territory from which they had expected to acquire energy.

It was as important for spiritual animals to be able to make this choice correctly as it was for the first animals to choose correctly between ingesting other objects or not — or for the first living organisms to choose between periods of growth and reproduction. In all three cases, choosing between the incompatible alternatives was required for the very existence of organisms of their kind. A wrong choice could mean the end of their reproductive cycles. In short, spiritual animals needed a behavior guidance system in the same sense that living organisms needed a biological behavior guidance system and heterotrophs needed an animal behavior guidance system. Spiritual animals already had a behavior guidance system for their social level animal (and biological) behavior. It was the use of a primitive language, and we have seen how it is a unique spiritual structural cause of their social level behavior. Since the animal behavior guidance system primitive spiritual animals already had was inevitably the locus of further evolution changes, it would take on the new behavior guiding function of making choices about war and peace.

What makes this possible, as we shall see, is a higher level of part-whole complexity in the linguistic representations (due to a higher level of neurological organization) that were used to coordinate the members behavior to act on other objects as a whole. That gave them the capacity for reflection, and since that is the mechanism of reason, reason might be called a new kind of behavior guidance system, with the function of making choices about war and peace.

But reason takes over the function of guiding the animal and biological behavior of spiritual animals, and thus, it is basically the same behavior guidance system that make spiritual animals possible in the first place. And since the higher level of neurological organization occurs within the spiritual animal’s behavior guidance system, the evolution of reason is more like the evolution of higher levels of neurological organization in the subjective and manipulative animal behavior guidance systems. In both cases, is a substantial increase in the power of the animal behavior guidance system. Thus, choices about war and peace will be treated as just a new kind of choice that is made by the spiritual animal’s behavior guidance system, much as it also found itself making biological choices, about growth and reproduction, for the beginning.

To be sure, it would not always have been difficult to make the right choice. There was no need to think twice about any remaining nonlinguistic hominids they may have encountered when resources became scarce. And as long as there were plenty of resources, spiritual animals could live at peace with one another — perhaps, under favorable conditions, for many generations of population growth.

Moreover, some other societies, at least, could be assumed to be friendly, for they were closely related biologically. Nomadic bands had to divide when their populations became too large to gather enough energy by wandering around, and individuals from such groups would recognize one another. Sometimes they would have strong attachments, which would lead them to treat members of other groups like members of their own group. And mating would give them a motive to maintain friendly relations with at least some other groups. They had inherited the primate instinct of mating outside the group, and it would continue to be naturally selected because of the advantages of avoiding inbreeding. However, since animal predators made it dangerous for solitary animals to travel alone, mating would take the form of exchanges of members between friendly groups that encountered one another.

There were, however, other spiritual animals around that would wage war on them. Thus, when they came upon other members of their own species, spiritual animals would inevitably make a distinction between Us and Them. It marked a fundamentally different attitude toward members of other groups, for those who were one of Us would be of the same “tribe” and would be treated in a friendly way, like other members of their own group. But members of nomadic bands from other tribes would be treated like groups that were (or might be) at war with them.

Furthermore, war was an extremely strong form of group level natural selection, which would adapt individuals more basically to membership in spiritual animals. War was dramatically different from the group level natural selection imposed on nomadic bands of hominids, for that was imposed by the habitat that primates invaded. Hominids had to travel in groups in order to protect themselves from the great predatory animals of the grasslands. Though hominid bands eventually imposed natural selection on themselves by the scarcity caused by their own population growth, group selection was not very strong, because not all their members died when times were hard. Survivors could join other groups or form new groups, as many other social animals do. With the advent of war, however, it was more common that all the members of a society would die at once. And even if some members were not killed, it would not be easy for language using subjects to move from group to group, at least, not when they used different languages.

The advent of war would, therefore, cause changes in the desires of the language using primates who adapted to it. They would evolve a pair of strong, but opposite desires, mirroring the choice forced on them by their spiritual nature. One would make them protective of members of their own group and members of others whom they recognized as one of Us, whereas the other desire would make them capable of aggression toward members of groups who were one of Them. One desire would draw them together, and the other would put them at odds with one another, making them suspicious and capable of brutality. Both desires would be strengthened by group level selection, since groups that lacked either desire would tend to be wiped out by losing in war. Thus, linguistic animals evolved desires that made them capable of both kinds of behavior involved in the choice of their spiritual nature forced to make.xcii

With strong desires to behave in opposite ways toward other groups, a choice between them had to be made every time one spiritual animal encountered another. Most of the time, there were at least some other groups around they recognized as members of their own tribe. And in peaceful regions, for example, where sources of energy had been divided up into territories, there was probably some warning of the arrival of bands of language-using primates who would wage war against them, so that they could be on the look out and prepared to fight. Between these extremes, however, the input for the choice they had to make was limited and unreliable.

Some distantly related spiritual animals might be given the benefit of the doubt because of their language. Language would be the main criterion for tribal membership among primitive spiritual animals, since the sounds, vocabulary, and surface grammars used by a language are conventional. And spiritual animals from the same tribe would normally be treated as one of Us.

However, spiritual animals from other tribes would be fair game — and, by the same token, quite dangerous. The more remote the relationship, the greater the danger, for it would be difficult to tell whether another group was of the same tribe. Even nomadic bands from the same tribe could be dangerous in special circumstances, such as times of extreme scarcity or when a string of easy victories made a group feel invincible.

And there would be spiritual animals about which they could not be sure. Some spiritual animals might happen on the trick of speaking the language of nomadic bands in the territory so that they would be treated as members of the same tribe and recognized it as a means to victory at war.

The behavior guidance system of spiritual animals had, therefore, to take on a new behavior guiding function. Spiritual animals had to choose between war and peace. That choice was forced on them by their own means of acquiring energy. It was a fateful decision, because choosing either war or peace in the wrong situation was a costly mistake. But in primitive spiritual animals, the choice was made in an animal-like way, by the relative strength of opposite desires, on the basis of whatever cues had evolved or been learned as triggers for those desires. Even when there was time for a leader to hear what everyone had to say, this behavior guidance system was liable to disastrous errors. They needed a more reliable way of making the basic choice entailed by their spiritual nature.

The nature of reflection. As linguistic animals, however, the need for a better way of choosing about war and peace could be met by a mechanism that enabled spiritual animals to “see into the minds” of other spiritual animals. Which kind of behavior would control the condition affecting their reproduction in the situation depended on the plans of the other spiritual animal. If the other spiritual animal was intending to wage war to control the territory and its resources, it would be necessary to fight or get out of its way. The worst mistake would be to take the other spiritual animal to be friendly when it is planning war. On the other hand, if the other spiritual animal had peaceful intentions, it would be better, considering the costs, to avoid war, although fighting might still be chosen in order to protect or gain territory from which to gather energy. In any case, to make the correct choice more reliably, it would have to be able to peer into the mind of the other spiritual animal and see the plans behind their behavior.

All any spiritual animal had to go on, however, was the observable behavior of the other spiritual animal. The animal system of representation had been shaped over eons to be maximally powerful in detecting physical aspects of objects. That would make them aware of the bodies making up the other spiritual animal, of their behavior and motion in space, but it would not always reveal what they needed to know about the other spiritual animal’s plans. To be sure, observation would sometimes make the choice obvious, for example, when they saw victims of a newly arrived group whom they recognized as belonging to their own tribe. Or when they were already under attack by the other group. But what members of the other group said, especially if said to them, would not necessarily be a trustworthy guide to the intentions causing their behavior. It might be disastrous, since the advantages of deception could be discovered by trial and error. But often they would not even be able to understand the others’ language.

It was nevertheless possible, in principle, to discover the other spiritual animal’s intentions from their behavior, for there is a regularity about social level behavior generated according to a plan of group action. What members of the other group do at one moment is part of a geometrical structure in time and space, and part of it is how they will behave in the future and how they would behave in certain situations. That is, after all, how social level animal behavior structures the thermodynamic flow of free energy toward increasing entropy to make things happen that would not otherwise happen.

If it were up to their naturalistic imagination by itself, the spatio-temporal geometrical structure about their behavior might be too complex or too subtle to be recognized. But this challenge could be answered. There was a way for them to recognize the pattern, because such behavior is guided by the same kind of structural cause as their own. By identifying the causes behind the other spiritual animal’s behavior, they could anticipate the parts of the spatio-temporal structure yet to come.

The mechanism responsible for this remarkable insight is basically the ability to use a language with psychological sentences, as well as natural sentences. We have seen how this higher level of neurological organization gives the linguistic brain a new form of imagination, rational imagination, by which they can think about psychological states and understand how they cause behavior (and beliefs). “Reflection” is an appropriate name for a mechanism that enables animals to use their own behavior guiding processes to simulate the behavior guiding processes going on in others.

Rational imagination can be used to explain or predict the behavior of subjects in any situation. Several psychological images may have to be predicated of the subject to represent all his relevant beliefs about the situation he is in and the various desires (or longer range intentions) that are at work in him, but they can all be held together as parts of the psychological image that is being predicated of a subject in the (perceived or imagined) local scene. They are all imposed at once as a temporary modification on one’s own worldview and goals, as if one were in the other’s situation. The changes that occur in one’s beliefs or intentions are the predictions one makes about the other subject, given those premises. The conclusions may be just inferences about what the subject would come to believe. But when it leads to new intentions, it is a prediction of the subject’s behavior.

To serve the function required by spiritual animals, however, rational imagination would have to take a somewhat different form. As suggested at the beginning, what is known is the overt behavior of the members of the other spiritual animal. Along with common background beliefs, they are assumed to have whatever additional, relevant beliefs that come from where they are located in the territory. In order to predict their future behavior, it is necessary to work backwards to their common intention by comparing possible sets of desires and beliefs and the intentions to which they would lead, for it is basically an inference to the best explanation of what is known. Thus, rational imagination would enable reflective subject to tell more reliably what they should do about war and peace.

Since being able to see into the minds of other spiritual animals would serve the urgent function of making correct decisions about war and peace more reliably, it would help control the condition that affects their reproduction so dramatically. Thus, the revolutionary change that begins the reflective stage of evolution is inevitable.

The evolution of rational spiritual animals on earth.Three evolutionary stages have been mentioned in this explanation of the origin of spiritual animals. The first was the evolution of animal societies of hominids; the second was the evolution of primitive spiritual animals; and the third was the evolution of rational spiritual animals.

Here is a brief review. (See the diagram of stages of evolution.) Although the first stage (stage 7) is just part of the radiation of primates, both subsequent stages require higher levels of part-whole complexity in the behavior guidance system than the previous stage. Each stage is predicted by the further relevant condition that a higher level of part-whole complexity enables the primary structure to control, though the evolution of primitive spiritual animals (stage 8) also involves a higher level of biological organization as well. The use of natural sentences evolves in hominid societies, because that makes it possible to generate social level behavior as the result of a shared intention in which different members make different contributions to a common plan. But since as population grows and resources become scarce, they use war to obtain energy, spiritual animals live in a dangerous world where another behavior guidance system is needed to make the momentous choice between war and peace. The use of psychological sentences evolves (stage9), because it makes explicit the reference to psychological states that is implicit in the input to the rational behavior guidance system. The choice between war and peace depends on the intentions of the other spiritual animals, and rational imagination enables them to represent psychological states as causes of behavior (and beliefs). The ability to infer the intentions of other spiritual animals from observations of the behavior of their members — that is, to see into their minds — makes it possible to choose between war and peace earlier and more reliably than primitive spiritual animals. Thus, these stages of evolution are inevitable, if evolution is the global regularity about change over time caused by how reproductive cycles add up in space over time, as we have found holds necessarily in a world of matter and space in time.

All three evolutionary stages are inevitable, but it is not clear from the data accumulated by paleontology and archeology which species are at which stages. Between hominids (stage 7) and reflective subjects (stage 9), there are linguistic subjects, or primitive spiritual animals (stage 8). The first and last of these stages are relatively clear. But it is not entirely clear when spiritual animals first evolved, and thus, neither is it clear when they first became rational.

If reason explains human nature, the third of these three stages, rational spiritual animals (stage 9), is represented by Cro Magnon Man (modern humans or Homo sapiens sapiens), because apparently nothing basic distinguishes us from them. Cro Magnon Man is the species that replaced Neanderthal Man (archaic humans or Homo sapiens) in Europe about 35,000 years ago. Not only are they anatomically indistinguishable from modern humans as far as fossils reveal, but judging by the wealth of artifacts that remain, ranging from finely chipped stone tools and weapons to jewelry and works of art, they also had a rich culture, like modern humans.

We have considered the possibility that Homo erectus had the use of a primitive language of natural sentences, but as we have seen, it is by no means required to explain what is known about them. And there is much to suggest that they were merely exploiting the limited capacity of animal cries and screams to serve as signs in coordinating behavior, comparable to wild dogs of Africa, except that they had new kinds of behavior make possible by structural imagination.

In archaic humans, such as Neanderthal Man, by contrast, there is evidence of a dramatic change in both the tools used and the capacity for verbal behavior. Flint tools and hafted stones indicate that archaic humans had a more advanced (Mousterian) culture, as we would expect of animals with the greater understanding of causal connections that comes with having a conception of states of affairs. There is also fossil evidence of changes in the larynx that suggest a much increased reliance on highly modulated sounds. Moreover, if archaic humans did have a primitive language of natural sentences, their capacity to coordinate behavior would explain why Homo erectus became extinct about the time that Neanderthal Man and other species of archaic humans showed up. That is, Homo erectus were the societies of hominids on which archaic humans preyed, before they took up war against one another.

Thus, it seems likely that that archaic humans were the first spiritual animals (stage 8). Given the ontological cause of revolutionary evolution, the replacement of Neanderthal Man by modern humans was inevitable, because Neanderthal Man would have to make choices about war and peace like animals, acting on the strongest immediate desire caused in the leader by instinctive or learned cues. Without the capacity for reflection, they could not see into the minds of other spiritual animals.

Neanderthal Man had occupied Europe since at least 200,000 years ago, but even though they had robust, muscular bodies, they were wiped out by slighter-bodied Cro Magnon Man within a few thousand years about 35,000 years ago. Warfare is an extremely strong form of group-level natural selection, and it would have given Neanderthal Man a great facility at the use of natural sentences. But if they were only primitive spiritual animals, they would be no match for the invaders, because without the use of psychological sentences, they could not figure out the intentions of Cro Magnon Man. On the other hand, Cro Magnon Man, as rational spiritual animals, could see into the Neanderthal mind. Thus, not only could they defend themselves against Neanderthal attack, but they could also intentionally deceive or trick Neanderthals, for they could understand the linguistic and other instinctive signs Neanderthals used to tell friend from foe and turn them to their own advantage.

It might be argued that Neanderthal Man and Cro Magnon Man cannot represent successive stages in the evolution of spiritual animals, because Cro Magnon Man could not have evolved from Neanderthal Man. There is some evidence (from their mitochondrial DNA) that modern humans had a common ancestor in Africa about 200,000 years ago or more, about the time archaic humans, such as Neanderthal Man, evolved. Furthermore, there is evidence of modern humans existing side by side with Neanderthal Man (archaic humans) in the Middle East some 90,000 years ago, long before their invasion of Europe, and the remnants of their technology at the time indicate roughly the same level of culture as Neanderthal Man.

These objections are not, however, decisive, because it is not necessary for Cro Magnon Man to have evolved from Neanderthal Man for them to represent a later stage of evolution. There were probably several species of archaic humans in existence 200,000 years ago, not only Neanderthal Man, but also other species of spiritual animals, and one of those others could have been the ancestors of modern humans. Since they must all have had the use of natural sentences, what made the ancestors of modern humans different may have been something about their neurological mechanism for using natural sentences that made it easier for them to try out the higher level of part-whole complexity required for the use of psychological sentences. Thus, the somewhat greater brain size of Neanderthal Man (about 1500cc on average, as opposed to 1350cc for modern humans) may indicate, not greater intelligence, but just a more cumbersome mechanism for using natural sentences.

Furthermore, it is possible that reason had already evolved 90,000 years ago, when both modern humans and archaic humans existed side by side in the Middle East, because this was during the last great ice age. The robust bodies of Neanderthal Man were well adapted to the harsh climate in Europe, whereas modern humans, with slighter bodies, were confined to the more temperate region of the Middle East. Thus, the greater capacity of rational spiritual animals to make choices about war and peace may have been used almost exclusively to kill Neanderthal Man only when Neanderthal Man ventured into their more energy-rich territory.

Indeed, the presence of Neanderthal Man may have enabled modern humans to live at peace with one another, because at those times when resources became scarce and war was a means of expanding the supply, modern humans could increase the territory from which they gathered energy by waging war against archaic humans, rather than against other modern humans. Modern humans may even have hunted archaic humans for food. In any case, the balance between archaic and modern humans could have been maintained for many thousands of years, because as long as the ice age continued, modern humans were unable to invade very deeply the territory occupied by Neanderthal Man. Thus, their radiation would have been stymied, like mammals who could not dislodge dinosaurs from the rich ecological niches to which they had become well adapted.

This would explain why Cro Magnon Man replaced Neanderthal Man suddenly 35,000 years ago, for there was a brief respite from the last great ice age at that time, which lasted for a few thousand years. The change in climate enabled modern humans, for the first time, to overcome the scarcity caused by their population growth by invading Neanderthal territory, and their greater skill at making war meant the extinction of Neanderthal Man.

That is, it would be analogous to the extinction of the dinosaurs. Although dinosaurs were so well adapted to their energy-rich ecological niches that they were invulnerable to invasion by mammals, the impact of an asteroid changed the environment so radically that dinosaurs and mammals had to complete in a new environment, and the inherent superiority of subjective to telesensory animals made it inevitable that mammals would replace the dinosaurs. In a similar way, Neanderthal Man was invulnerable to replacement by modern humans until a break in ice age occurred and modern humans could take advantage of their inherent superiority to invade Neanderthal territory and replace them. Then, when the ice age returned a few thousand years later, Neanderthal Man was already gone, and modern humans could learn how to survive in the colder climate without competition from archaic humans. On this account, therefore, the sudden appearance of Cro Magnon Man in Europe about 35,000 years ago would be just another instance of catastrophic changes “shaking out” the natural kinds of organisms according to their inherent superiority.

Cro Magnon culture differed from Neanderthal culture in just the ways that we would expect reflective spiritual animals to differ from primitive spiritual animals. As rational animals, they could not only see into other minds, but also reflect on the causes of their own conclusions about how to behave and what to believe in the process of drawing them. Thus, instead of a language of just natural sentences for coordinating behavior and passing technology on by imitation, the culture passed down from generation to generation by Cro Magnon Man was an accumulation of arguments about what to do in certain situations and what to believe (as will be explained more fully in the next section). And their culture would reflect the danger of living in a world where war was always possible.

Once Neanderthal Man was no longer around to prey on, it was inevitable that modern humans would resort to war against one another, since the growth of their population caused scarcity and they knew the value of war from battles with Neanderthal Man. But when reflective spiritual animals turned the weapon of war against one another, they had to determine, as primitive spiritual animals did, whether other groups they encountered were of the same tribe, for there were normally at least some other groups with which they had friendly, in-group relations. Tribal membership was the main way of telling whether other groups they encountered were one of Us or one of Them in choosing between war and peace, but tribes of reflective spiritual animals were based on sharing a culture of accumulated arguments, including legends and myths, rather than simply use of the same language. But when they decided to treat the other group as part of their tribe, they made themselves vulnerable, and thus, there was always the danger that other groups were gaining an advantage over them in war by pretending to share their culture. This was a trick that had probably worked well against Neanderthal Man. By pretending to speak their language of natural sentences, primitive spiritual animals would have been deceived into treating their enemies as friends. More subtle forms of deception might be used against other rational spiritual animals.

The danger of war would explain, therefore, the sudden appearance of highly refined artifacts, such as the ivory figures of animals which were apparently worn as jewelry, after Cro Magnon Man invaded Europe. It would provide credible evidence of their tribal membership. Groups in a tribe might identify with different kinds of animals, and thus, tribal membership could be represented by groupings of animals and, within tribes, nomadic bands could keep track of their relationships to one another by passing down stories about the animals with which they identified from generation to generation. Groups could give credible evidence of which group they were and which tribe they belonged to by the kinds of animals depicted in their jewelry. The ornaments were credible, because the art involved in creating them made it too difficult to fake them. Thus, highly refined works of art were good evidence about one another’s tribal membership, and that made it easier for groups from the same tribe to establish trust. Considering their value in making reliable choices about war and peace, there was a strong selection pressure at the group level, favoring skill at art as well as facility in the use of psychological sentences to reflect on the reasons for their behavior.

In other words, the lack of highly refined ornaments and ivory figures among the remnants of modern humans in the Middle East around 90,000 year ago does not necessarily mean that reason had not yet evolved. Their level of culture is what might be expected of rational beings, if warfare was reserved for use against the easily recognized archaic humans that were always on the frontier of the territory from which they were excluded by their slender bodies. Under the circumstances, all modern humans may have been able to treat one another as part of the same tribe.

What ontological philosophy implies about the evolution of reason is, therefore, consistent with what is known about the ancestry of human beings on Earth. Indeed, it accounts for those facts better than the theories currently being discussed by archaeologists. But it should be emphasized that ontological philosophy would not be refuted by evidence that contradicted the interpretation of the archaeological evidence that has been sketched here. It is also compatible with the hypothesis that modern humans in the Middle East some 90,000 years ago simply had not yet evolved the use of psychological sentences. It is, however, an empirical question which species on Earth are the ones that represent those stages. All that we know on ontological grounds is that there must have been a stage of evolution between societies of bipedal hominids and rational animals, because reason can evolve only in primitive spiritual animals, which already have the use of natural sentences. No one denies that societies of hominids are a late phase in the radiation of higher primates (stage 7). Nor does anyone doubt that Cro Magnon Man was a form of modern humans, and if the nature of reason as explained here accounts for human nature, Cro Magnon Man must represent the rational spiritual stage of evolution (stage 9). Thus, it remains only to decide which species represents primitive spiritual animals (stage 8). On the basis of what is currently known about our past, I have suggested the reasons for believing it is represented by Neanderthal Man and other archaic humans. But new evidence might justify assigning this role to another species.

Cultural evolution at the rational spiritual stage. Gradual evolution during the rational spiritual stage gives individual humans greater facility in using psychological sentences, but the change that inevitably occurs during this stage is not limited to traits that depend on the biological behavior guidance system.

The use of a language with psychological sentences transforms linguistic interactions into an exchange of arguments. As variations on arguments are tried out more or less randomly, the many individual judgments about which of competing arguments to accept is a rational selection from among them, and so the arguments accumulated in a spiritual animal and passed on from generation to generation evolve. Culture undergoes a gradual change in which arguments start off simple, uniform and weak and become increasingly complex, diverse and powerful.

In other words, cultural evolution is a form of reproductive causation contained within spiritual animals. But since it involves the rational selection of random variations on arguments, culture tends to discover the true, the good and, as we shall see, the beautiful.

In order to show that cultural evolution is part of the rational spiritual stage of evolution, I will explain how cultural evolution is a form of reproductive causation contained by rational spiritual animals. But instead of trying to trace the entire course of cultural evolution, I will show how the natural perfection toward which rational level culture evolves inevitably includes three dichotomies that divide arguments into four groups, without only religion to paper over the differences among them.

Reproductive causation contained by rational spiritual animals. Cultural evolution is a reproductive global regularity that occurs in spiritual animals. The reproductive cycles and the space in which they add up over time are constituted by rational spiritual animals. Thus, the essential nature of rational spiritual animals contains the ontological cause of this gradual evolutionary change. It depends on the relationship between their social and cultural aspects.

To recapitulate, reason evolved in spiritual animals that already had the use of a primitive language. Language is what gives a group of multicellular animals the structural cause needed to coordinate the members’ behavior as social level behavior, and made spiritual animals a new form of life on the social level of biological organization. But language worked so well, as we have seen, that it eventually forced spiritual animals to choose continually between war and peace. That choice was to made more reliably with the use of psychological sentence evolved, but that made the individual members reflective, so that their behavior was caused by reasons. Reason became the system for guiding not only the behavior of the spiritual animal, but also individual behavior.

The unique way that the individual and social levels of biological organization are combined in rational spiritual animals makes it possible for reason to evolve more and more power to control conditions in the world. The structural cause of social level behavior in spiritual animals is a special kind of material structure which I am calling a “spiritual structure.” A spiritual structure is actually two different kinds of structures bound together by the use of language, one under the social aspect and the other under the cultural aspect, and both are structures of the spiritual animal as a whole.

The structure under the social aspect is the fact that language-using animals stick together and are in continual interaction (including linguistic interaction) as parts of an organism at the social level.

The structure under the cultural aspect includes all the linguistic structures generally shared by members and which individual brains born into the spiritual animal normally acquire, including the language itself and the set of beliefs and intentions that come to be shared by its members because of the various linguistically mediated ways they normally interact.

Since the structures under these two aspects of the spiritual animal are different, they can interact with one another.

Thus far, we have focused on how the linguistic structures under the cultural aspect affect the social aspect. In primitive spiritual animals, the use of language distributes plans of social level behavior to the members in a way that enables each individual to know what he is supposed to do, and that makes it possible for the social level behavior of spiritual animals to act on other objects in space (or organize interactions of its own members as social structure). More generally, language enables the members to share beliefs and intentions as a worldview, and culture generates customs, institutions and other regular aspects of social level behavior.

There is, however, an equally important effect that the structure under the social aspect has on the cultural aspect, because the linguistic interactions can affects the content of the linguistic representations being exchanged among the members and, thus, their beliefs and intentions. Though this effect already occurs inefficiently in primitive spiritual animals, it becomes, with the evolution of psychological sentences, a normal part of almost linguistic interactions. In rational spiritual animals, as we shall see, the linguistic representation exchanged include arguments (that is, conclusions about how to behave or what to believe that come together with reasons for them), and such an exchange constitutes another contained form of reproductive causation, this time, one in which the arguments accumulated as culture evolve in the direction of natural perfection for arguments of its kind, which is to discover the true, the good and the beautiful, albeit within certain inherent limits.

In primitive spiritual animals, the social aspect already has important effects on the cultural aspect. The linguistically mediated interactions among the members is what distributes the plan among the members in a way that assigns them different roles to play in social level behavior. But linguistic interactions were not necessarily as one sided as that model suggests.

Guiding social level behavior was not necessarily just a matter of following the leader’s instructions. Members could also pool their knowledge of the current situation, since everyone could speak natural sentences as well as understand them. The context and manner of the utterance would make it clear whether the sentences were meant to assert a description of what is, to ask about a state of affairs, or merely to present a possibility to be taken into consideration.

Members could also pool their understanding of efficient causation in the natural world, since naturalistic imagination gave them all the capacity to see states of affairs as causes and effects. Thus, spiritual animals could accumulate increasingly complicated techniques for controlling natural processes. For example, instead of carrying fire with them, they could acquire the skill to start fires when needed.

Finally, since each member could understand how the leader’s plan was supposed to attain goals set by their own desires, their willingness to follow his instructions would tend to depend on whether it made sense to them. The adoption of a plan for the immediate situation would the result of a linguistic interaction between the leader and the members.

In rational spiritual animals, however, this effect of the structure under the spiritual animal’s social aspect on its cultural aspect becomes much stronger, because context is no longer needed to indicate the roles that spoken sentences are meant to play in determining beliefs and behavior. The use of psychological sentences enables them to represent psychological states as causes in the process of guiding behavior (or determining beliefs), and that makes it possible for speakers, in their attempt to agree about what the spiritual animal should do, to make explicit what roles they mean their sentences to play. A leader is less important to the spiritual animal’s behavior guidance system , because every member can make arguments at any time that everyone can understand.

The exchange of arguments in spiritual animals is the ontological cause of cultural evolution. Arguments are like “organisms” that reproduce as one member of a spiritual animal makes the argument and another member accepts it as a cause of what she believes or does. Such reproductive cycles add up in the “space” of spiritual animals over time to a form of natural selection. They cannot go on reproducing for ever, because there are only so many members of a spiritual animal. But since what determines which one’s go on is, as we shall see, rational selection, the arguments accumulated as culture in a spiritual animal gradually evolve in the direction of natural perfection for “organisms” of their kind, that is, arguments that discover the good and the true.

In order to show the inevitability of this global regularity within rational spiritual animals, let us consider the nature of arguments and the nature of rational selection. That will enable us to see why gradual cultural evolution is inevitable.

The nature of arguments. Though the original function of reflection was to control a condition affecting the reproduction of whole spiritual animals, it is the members who had the faculty of rational imagination, and so it was inevitable that individual subjects would also use reflection to see into one another’s minds and to understand the causes of their own behavior.

Self-reflection. Reflection is self-reflective when psychological sentences are used to predicate psychological states of oneself, instead of another subject. It may be, in the first instance, just a way of monitoring one’s beliefs and desires, which enables one to report how things seem, that is, that one has a certain belief, rather than just making an assertion about the world. Or to recognize that one has a desire, rather than just asserting that something is good. The faculty of rational imagination is required for self-reflection, because that is what enables one to see psychological states as psychological states, rather than simply to have them.

The developmental stage at which children acquire the use of a faculty of rational imagination has been identified in children.xciii It is manifested as the capacity to think about subjects as subjects. Until about the age of three, children cannot distinguish how something appears from what they believe it is. When they mistakenly believe that a molded piece of wax is an apple and they are shown their error, they correct their belief, but they insist that they always thought it was a piece of wax and assume that everyone else will also see it as a piece of wax. By the age of four or five, however, children can understand that it appears to be a piece of fruit, even though they realize it is not, and they expect that seeing it will cause others to form mistaken beliefs about it. The difference is that the older child has the capacity to think about people as forming beliefs because of how things appear in perception, and thus as having beliefs that may differ from what really exists. To be sure, three-year-olds are already able to use such words as “see” and “believe.” But they assume that what is seen or believed is always the same as what really exists, as if there were no distinction between appearance and reality.

The cognitive development of children recapitulates the change that occurred in the evolution of primitive spiritual animals into rational spiritual animals. A whole new range of facts about the world comes into view with the capacity to think about subjects as having psychological states. They include facts about desires as well as beliefs. Instead of simply having desires or seeing objects as desirable, the reflective subject can think of individuals as having desires, whether or not the objects are desirable or attainable, and see their behavior as being caused by them. That is, after all, what was crucial in the original function of reflection, making choices about war and peace.

Self- reflection is not, however, just the capacity to monitor one’s psychological states. In representing one’s psychological states to oneself as psychological state, self-reflection represents them as causes, and that changes the nature of the causes of one’s behavior and beliefs.

Rational imagination enables subjects to see the difference that having any perception, belief, desire or intention would make in the choices they make (or on the beliefs they form). By seeing actual psychological states against the background of what is possible, subjects are able to represent the causes of their own behavior (and beliefs) as causes of their behavior in the very process by which they are causing behavior.

But as rational spiritual animals evolve, that self-reflective power becomes a integral part of the animal behavior guidance system, so that reflection on the causes of one’s behavior (or beliefs) makes a difference in what one does (or believes). That is, the causes of behavior become causes that are represented as causes of behavior as a causally relevant part of the process of causing behavior. That is how they earn the special name. “reasons.” Though reasons are still efficient causes of behavior, their power to cause behavior comes to depend on them being represented as causing behavior.

Reasons. The transformation of animal causes of behavior into reasons makes animals more powerful, because when the causes of behavior must be represented as causes in order to cause behavior, the mechanism that represents them (the linguistic system of representation) can control behavior. That is, it brings the animal causes of behavior under the control of a higher level behavior guiding process. That higher order process is located in the linguistic hemisphere of the forebrain, and we have already seen how the linguistic system of representation acquired control over the causes of behavior.

Even hominids had a desire to submit to the leader, which derives from the dominance hierarchy of animals. But with the evolution of language, the desire to submit to a leader became the desire to do what the leader said, that is, to conform one’s behavior to a linguistic representation of it. Thus, when the use of psychological sentences transformed the members into reflective subjects, the desire to submit to a leader became a desire to submit to reason (that is, to act only when the causes of behavior are represented linguistically in a certain way in the process of causing behavior).

This evolutionary transition is recapitulated in human beings at adolescence. Though the child submits to the plan imposed by her parents, a radical change takes place at puberty. The adolescent starts to take control of his own behavior, often rebelling against parental limitations, because what is causing his behavior are now causes represented linguistically in a different way, namely, as the conclusions of practical reasoning. The burden of being responsible for his own choices takes the form of worries about his identity. This is the process by which the language-based power of reason, which is located in each individual, takes over control of individual behavior.

As will be explained more completely later, this rational control of behavior gives the individual increased power to control relevant conditions. It is a kind of “autonomy” that subjects have because they are rational, or the “autonomy of reason.”

Once the reflective subject has the ability to act on the results of such a reasoning process, psychological states are not merely causes of behavior on which the subject can reflect, but rather a new kind of cause of behavior. For example, though desires are seen as causes of one’s behavior, the capacity to represent the causes of one’s behavior as causes in rational imagination makes it possible to reflect on all one’s desires, including those that will be felt only in the future or under other circumstances. Thus, it is possible to figure out the best way to behave in, say, a series of situations to satisfy them all. This is a form of practical reasoning, and in rational subjects, reason wrests control of behavior away from the animal causes of behavior (mainly, desires), because the desire to submit to reason enables the intention formed by practical reasoning to generate behavior even when it is opposed by currently strong animal desires. Rational subjects can, for example, delay gratification. Nor is this the only way reason guides behavior independently of strongest (other) desire at the moment, for as we shall see, reason even enables the subject to pursue goals that do not control conditions that affect his own reproduction and to do what is good for the spiritual animal.

Reasons can also change the way that beliefs are formed. Beliefs are most commonly caused by perceptions. But beliefs are all connected (because the objects they are about are all related in space and it is possible to call up the states of affairs in which they are involved from the map of one’s territory built up by spatial imagination). Furthermore, episodic memory for particular past events (another form of the capacity to record memory groups in sequences) sometimes makes it possible to reflect on the perceptions that caused particular beliefs. Thus, by reviewing the reasons for one’s beliefs, comparing the relevance of current perceptions with past perceptions in causing beliefs, and the like, it is possible to correct errors and make more reliable judgments about what is true. For example, by knowing which beliefs were caused by perceptions in the past, it is possible to dismiss current perceptional illusions or to resolve ambiguous perceptual input.

Reasons and conclusions.When behavior and beliefs are caused by reasons, the social aspect of the spiritual animal has a much more powerful effect on the cultural aspect, because the linguistic representations being exchanged can contain conclusions together with reasons for them, that is, arguments.

This is the change in the behavior guidance system of the spiritual animal that was suggested above by contrasting the primitive spiritual animal’s use of a leader to distribute a plan publicly to all the members and a processes in which members come to agree about which plan is best by arguing with one another about it. The increased power of linguistic interactions to coordinate the members’ behavior comes from how the use of psychological sentences frees reasoning about what to do (or believe) from dependence on the context provided by a leader.

This change resembles the earlier transition from nomadic bands of hominids to primitive spiritual animals, where the increased power of linguistic interactions to coordinate the members’ behavior came from how the use of natural sentences freed the primate cries and screams from dependence on context for their meaning. In both cases, context was no longer needed to align imagination in different animals, because verbal behavior included grammatical markers that represented how the listener was to operate his imagination. Not only was a leader not needed, but members could be drawn into agreement anywhere about how to behave (or believe) in any situation. That increased the power of spiritual animals in a more far reaching way, because eliminating the need for context in arguing made it possible for arguments themselves to accumulate as part of the culture and, thus, for culture to evolve by rational selection.

Arguments are simply conclusions about what to do (or what to believe) that come together with reasons that recommend them, that is, with other propositions asserted as causes for accepting the conclusions.

The mechanism by which reflective subjects can consider arguments is implicit in their ability to use psychological sentences. The behavioral schema for a psychological sentence generates covert nonverbal behavior that operates on images in the sensory input system. It not only constructs a naturalistic (or psychological image), but also represents it as having a causal role, such as a belief or desire, and predicates that psychological state of a subject. The psychological state is seen against the background of what is possible by rational causation, such as the roles it might play in causing behavior (or belief), and thus, the psychological linguistic act can be used to predict or explain what the subject will do (or believe). This rational explanation can then be expressed in over verbal behavior. For example, “Joe went to the ridge, because he believed that the deer were in the valley beyond and he wanted to check on them.”

Arguments are a modification of this ability to understand rational-cause explanations. When considering the reasons for a conclusion, it makes no difference which rational subject the psychological states are attributed to. Behavior guidance systems all work basically the same way. Everyone shares much the same background beliefs as their worldview. And they are all moved by the same kinds of desires. Hence, the reference to a particular subject as the grammatical subject is generally suppressed in formulating arguments. Thus, arguments are like anonymous rational cause explanations (or predictions).

It is still necessary, however, to include verbs of propositional attitude (or grammatical markers for them) in order to refer to the proposition, rather than what the proposition represents, and to indicate its (causal) role in the argument. For example, “In order to check on the deer, go to the top of the ridge, because they can be seen from there.” The argument must enable the listener to reconstruct the inference in her own rational imagination, and in more complicated arguments, the conclusion may depend on imposing several psychological states on rational imagination simultaneously, or there may be a series of conclusions. Thus, some propositions may be referred to explicitly as reasons for other proposition, or the inference may be indicated by, “and thus” or “because.”

Rational selection. On any given issue, however, there may be arguments for different conclusions. A judgment must be made about which is correct, and it is made by each individual. That is the rational selection of arguments, and as we shall see, that is why the general exchange of arguments among members of a spiritual animal gives rise to the gradual evolution of culture by rational selection.

Judgment. According to this explanation of the nature of the reflective level of neurological organization, each individual is able to judge the correctness of any argument about what to do or believe in any situation, because each has a worldview in which to test its coherence with other beliefs and intentions.

Each individual has a more or less complete set of beliefs about the natural world, because beliefs are all ultimately about objects located in space, and since space is whole, they must all be related to one another in the subject’s mammalian map of his territory. But that is not only to have beliefs about the locations, geometrical structures, and properties that they have been perceived as having, but also beliefs about how they can change locations and how they would interact (since they are objects represented in spatial and structural imagination). And in naturalistic imagination, the worldview also includes the states of objects in space and how they are involved as causes and effects in the natural world. And corresponding to the endurance of the natural world through time, their view of the natural world is a history that includes whatever they remember about the histories of objects in their territories.

Each individual also has a more or less complete set of beliefs about the subjects in their world. Subjects are also objects in space, and though their behavior is explained by their psychological states (as reasons), all the beliefs and intentions by which the behavior of members of their spiritual animal is explained would have to fit together as a whole both in space and over time. Though there is more to be said about it, their worldview would include a social world as well as a natural world, each explained in its own way.

Finally, each individual would has more or less complete set of intentions about what to do in any situation, both at the individual level and regarding the behavior of the spiritual animal as a whole. In addition to any particular plans they may have, it would include intentions about how to choose among goals when conflicts arose. In short, they have certain values.

Though such a worldview is worked out in detail only as far as it was useful or questions about it had to be handled, there is a coherence about the beliefs and intentions it contains, because everything is seen in rational imagination as part of a single world, a natural world of objects in space, including subjects as a special kind of object, where certain basic regularities hold. The worldview is the background against which arguments are tested.

Merely fitting together comfortably with the worldview is all that was required to accept new beliefs about the world, if there is some reason to believe them, such as perception or reports of perception. To report, for example, “I saw deer in the valley,” is to argue, in effect, that it is true for a certain reason, and unless there is some reason to distrust the reporter, it is a good argument. .

Arguments whose conclusions contradict one’s worldview in some way require reasons that can dislodge already established beliefs. For example, in addition to some positive reason for holding the new belief, there may be reasons for doubting the grounds of the old belief. By reflecting on her worldview, it is often possible to surface the grounds for any particular belief by imposing the alternative on imagination and seeing what else would have to change. If those grounds are not themselves well grounded, she may be convinced by the argument.

In some cases, it is possible to dislodge current beliefs by showing that the new belief is entailed by other beliefs that the subject already holds because of regularities to which the subject is committed by the very structure of rational imagination or which are firmly established for other reasons. Or in more complex examples, whole sets of beliefs about some aspect of the world is challenged by an alternative set, and the judgment about which is correct depends on which set was simpler and fit into the background more completely.

The interests of reason.Though each individual judges which arguments to accept, it is not just a whim. Rational subjects judge arguments in the same way, and making rational selection selection in the interest of reason.

Since arguments are tested by their coherence with one’s worldview, their acceptability depends on whether they make one’s worldview more coherent as a whole. It is possible to tell which argument results in the most coherent worldview, because arguments are considered in rational imagination, where the actual (or proposed) is seen against he background of what is possible. Imagination connects all one’s beliefs and intentions together, and so the judgment about whether to accept an argument is ultimately an aesthetic judgment. To use imagination to tell whether one set of beliefs or intentions is better than another is to judge arguments by the beauty of accepting their conclusions, that is, by whether it would be unique among the alternatives in basically the same way as natural perfection itself, that is, making the most out of the least.

Truth.Though the means of judging is coherence, that does not mean that beauty is the goal of reason. Since the foregoing examples are theoretical arguments, that is, arguments about what to believe, the goal of reasoning is truth. The conclusions are accepted because it seems that the propositions correspond to the world. That is how the goal appears to rational subjects, because arguments for believing certain propositions are judged by whether the states of affairs they represent are part of the world as represented in perception and, more broadly, in one’s worldview.

Goodness.There are also arguments about what to do, and in the case of practical arguments, reasons’ goal is to know what is good. But the judgment about whether to adopt the proposed intention urged by the reasons offered depends on how the intention fits together with established intentions about how to deal with the relevant situations. Coherence in this case depends on the intention fitting together with the whole set of intentions, including policies and plans, for dealing with all the situations that arise over time in leading the life of a reflective subject as part of a spiritual animal, and thus, it also requires a judgment based on overall coherence. At this stage of evolution, the intentions are mainly caused by their desires, though as we shall see, that may not be recognized. And since plans for satisfying all their desires depend on an aesthetic judgment, about how they fit together, rational subjects often pursue goals that are good for reasons other than affecting their own reproduction. But established intentions, or values, by which the conclusions of practical arguments are judged are usually seen at the rational spiritual stage as fixed by ancestors, gods, or nature.

Beauty.Truth and goodness are, therefore, interests of reason. But since the truth and the good are judged by rational coherence, reason necessarily has an inherent interest in beauty as well. That is the means that reason uses to judge them, though it may not be recognized as an aesthetic judgment. But the rational interest in the beautiful does guide reason explicitly in other ways, for example in productive reason, that is, in making products that are beautiful, including the fine arts. Since beauty is the same kind of unique optimum as natural perfection, which marks the direction of evolution, there is a sense in which the ancient Greeks were correct in holding that art is the imitation of nature. Art is artificial perfection.

These interests are the interests that rational subjects recognize they are pursuing by reasoning about what to believe and what to do. But given the essential nature that reason has as the behavior guidance system that evolves at the rational spiritual stage, we can see that these interests are actually aiming at maximum holistic power for rational beings, that is, that they contribute to natural perfection.

Though rational subjects may see truth as a correspondence between their linguistic representations and appropriate aspects of the world, they do not understand the nature of the correspondence completely. They take the world to be what appears to them in perception, and thus, they are thinking about a relationship between representations in rational imagination and representations caused by sensory input. In fact, the correspondence that makes the true holds between both of those kinds of representation and aspect of the natural world. But judging the truth of beliefs by the correspondence that seems to hold at the rational spiritual stage usually still has the effect of discovering the actual correspondence, which contributes to the power of the behavior guidance system to guide behavior.

Likewise, rational subjects at this stage see the good as something about what is judged to be good, and thus, once again, reason’s interest seems to be correspondence too. But since the only explanations of the nature of goodness at this stage are religious, it is not clear what practical conclusions must correspond to. From the perspective of ontological philosophy, however, we can see that what correct conclusions about how to behave correspond to is what contributes to the natural perfection of the whole of which they are part. This is not as straightforward as it may seem, for as we shall see, the pursuit of goals may contribute to the natural perfection of rational beings even though they do not control conditions that affect their own reproduction. Because of the autonomy of reason, as we shall see, pursuing goals that are good for other reason, or “optional goals.” is part of the natural perfection of rational beings.

Because rational selection is made by maximizing the coherence of one’s worldview (including intentions), the true and the good are recognized by their beauty in the faculty of imagination. But from our ontological perspective, we can see that even judgments about the beautiful are correct in virtue of corresponding to an aspect of the world. In this case, it is correspondence to natural perfection itself, that is, the state that makes the most of the least. Such optimal states stand out in rational imagination, because that is the ability to see them against the background of what is possible.

Arguments as reproducing organisms. The capacity to argue about anything anywhere, with individuals judging for themselves what is true, means that the linguistic interactions in a spiritual animal constitute a new, contained form of reproductive causation. In this case, what evolves is culture, and it evolves in the direction of knowing the true, the good and the beautiful.

Evolutionary change, in general, is a global regularity whose ontological cause is reproductive cycles and how they add up in space over time. What evolves are material structures that go through cycles in which they not only reproduce themselves, but also do some kind of non-reproductive work. But since evolution depends on a natural selection from those material structures, there must also be variations on them that do different kinds of non-reproductive work, though they all reproduce in the same way, and such variations must continually be tried out randomly. A selection is made by success in reproducing. A selection must be made, because eventually it is not possible for all of the material structures to reproduce. But since which material structures succeed depends on the kind of non-reproductive work they do, evolution is inevitably change in the direction of reproducing structures whose non-reproductive work controls conditions that affect their reproduction.

In the case of biological evolution, the reproducing structures are organisms (or proto-organisms). They impose natural selection on themselves by their own reproduction, because their population increase causes a scarcity of the resources (free energy, if nothing else) in the region needed to go through reproductive cycles. And they evolve in the direction of greater power, because those random variations whose non-reproductive work is best able to promote their reproduction under those conditions are more likely to succeed in reproducing.

We have already encountered one contained form of reproductive causation in tracing the course of evolution. Neurological development is the evolution of behavioral schemata in individual brains by reinforcement selection, and as we have seen, it is change of the brain’s memory groups of neurons in the direction of behavioral schemata that internalize the regularities involved in spatial causation, structural causation, and efficient causation, as well as the words and grammatical structures of natural languages themselves.

Neurological development is, however, only the first the three such contained forms of reproductive causation. The second is cultural evolution by rational selection, and as we shall see, the third is economic evolution by capitalist selection. In each case, evolution is a global regularity caused by how cycles of reproduction add up over time in space, or in the “space” provided by some evolved structure (respectively, the brain, a spiritual animal under its cultural aspect, and under its social aspect).

In the case of cultural evolution, the “reproducing structures” are arguments. Arguments can reproduce, because they can be expressed in overt verbal behavior, making it possible for listener who understands them to be convinced by them. That is, they reproduce themselves in the brain of other members of the spiritual animal. But reproduction is not complete, unless the listener not only understands the argument constructed in rational imagination, but is also convinced by it, because the non-reproductive work of an argument is its effect on how the individual behaves in certain situations or what she believes on certain topics.xciv

Random variations on arguments are introduced in various ways. Sometimes reproduction is not perfect, and the argument tried out in the new brain’s imagination is different from that of its proponent. Since they are constructed in rational imagination, variations may be tried out by accident or when trying to think about something else. Dreaming may play a role in generating random variations on arguments, since arguments are constructed by linguistic behavioral schemata and, as we have seen, the function of dreaming in mammals may be to sort out and reassemble parts of behavioral schemata involved in satisfying desires. New arguments can also be introduced when one spiritual animal encounters another, by a process of cultural diffusion. And some variations are likely to be tired out as all the arguments accumulated as the culture of a spiritual animal are passed to the next generation in the process of enculturation.

What corresponds to species of organisms are kinds of arguments. Arguments are differentiated by the situations to which they apply, though there are two classes of situations, one class involving the choice of what to do in the situation, and the other the decision of what to believe on some topic. Thus, arguments of each kind are like a species adapting to its ecological niche, and random variations on each kind of argument compete with one another in each ecological niche, like members of a species with different traits.

As arguments go through reproductive cycles, some reproductive cycles must come to an end. Each brain contains a full set of ecological niches for arguments, at least, in principle, because each individual faces all the situations in which a choice must be made about what to believe and what to do, if only in imagination. But there are only so many brains in the spiritual animal into which they can reproduce themselves. Thus, arguments impose a natural selection on themselves by their own reproduction, in much the same way that population growth makes resources scarce in biological reproduction, because as an argument reproduces into one brain after another, it fills the ecological niche for arguments of its kind. When no member of the spiritual animal lacks a belief or intention for the relevant situation, its reproductive cycles come to an end.

Given the scarcity of brains into which arguments of any kind can reproduce means that variations on arguments of each kind are competing to control the behavior of individuals in each situation. Variations on arguments can be tried out, even when every member already has a more or less complete worldview, because new arguments can be considered in rational imagination, for example, when one member makes the argument to another. To be selected, however, the argument must change the subject’s intentions (or beliefs). That is possible, because arguments include reasons that may dislodge the intentions or beliefs that already fill the relevant ecological niche. Success in reproducing depends on the rational subject’s judgment about which conclusion fits together more coherently in his worldview. That is, natural selection is by rational selection.

Gradual evolution of rational level culture. This is a form of reproductive causation, though it is contained within and sustained by rational spiritual animals, and thus, the arguments accumulated as culture should evolve gradually in the direction if maximum holistic power. As arguments are exchanged in spiritual animals, random variations on them are tried out, and there is a rational selection from among them imposed by the judgment of its members. It is a global regularity because it is a change in the arguments that are accumulated as the spiritual animal’s culture, and what is regular is that they tend to change in the direction of greater power to control the conditions that affect their reproduction. Since the reproduction of arguments depends on their making the subject’s worldview more rationally coherent, culture changes in the direction of discovering the true, the good and the beautiful, which is the source of the power of reason in guiding behavior.

Cultural evolution is not, however, biological evolution. The material structures going through reproductive cycles are just arguments that are expressed verbally by public linguistic representations and can be constructed in rational imagination, where they cause the brain to make an inference, from premises to conclusion. Their rational selection depends on whether accepting them as sound results in a more coherent worldview. Thus, cultural evolution has some unique features and some special limitations.

Like any stage of gradual evolution, arguments start off simple, uniform and weak, and as they evolve by reproductive causation, they become increasingly complex, diverse and powerful. In general, power is likely to increase, because the argument accepted for any given situation is likely to be closer to the truth than the others completing with it. And as situations calling for a choice about what to believe or intend are distinguished from one another, the arguments accumulated as culture become more diverse. Before long, therefore, a worldview evolves with beliefs and intentions for all the relevant situations.

Arguments do not, however, become complex in the same way as reproducing organisms in biological evolution, because arguments are not independent of one another at the ecological level. The ecological niches for arguments are the situations calling for choices about what to believe or intend, and there are similarities as well as differences among such situations. The reasons that hold in one situation are likely to hold in the others that resemble it, and since arguments must often dislodge established beliefs and intentions in order to be rationally selected, arguments that take account of such similarities are more likely to be accepted.

Discovering the true and the good is not, therefore, just a matter of accumulating beliefs about particular facts and making choices about how to behave in particular situations. It also includes the discovery of principles covering entire ranges of situations, uniting the arguments for them. Principles tend to become more general as rational level culture evolves. At a relatively early phase during the rational spiritual stage, for example, principles would evolve to decide which direction is south, where the deer have gone, what caused someone’s illness, who committed the crime, how to avoid hazards of weather, etc. And such principles become subsumed under more general principles as culture evolves.

In more advanced cultures, therefore, whole armies of arguments, with several echelons of command, may confront one another in the battlefield of linguistic interaction within a spiritual animal. There would then be profound theoretical disputes, because both armies, each with many individual arguments serving under a different set of principles, would deal with the same range of situations. Individuals would have to judge which theory would make their world views more rationally coherent, and the disputes may be so deep and global that there is no obvious grounds for choosing between them.

In less disputatious culture, however, principles may evolve without any recognition that alternative principles are even possible. The arguments accumulated in such cultures could become integrated in an aesthetically satisfying way, and yet all of them make the same basic mistakes.

Principles become explicit at the rational spiritual stage for the same reason that subjective animals acquire a general conception of the structure of space and manipulative animals acquire a general conception of geometrical structures. It is a consequence of the neural mechanism that gives subjects a faculty of imagination and how behavioral schemata evolve within it by reinforcement selection.

Arguments are constructed by linguistic behavioral schemata contained in the frontal neocortex, and they use covert behavior to act on the subject’s worldview in much the same way as locomotor schemata use covert behavior to act on the map of the mammalian territory and that manipulative schemata use covert behavior to act on object images within its local images. Covert behavior calls up sequences of images, but the evolution of kinds of covert locomotor or manipulative behavior establishes labels for calling up kinds of sequences of images. With the development of generalized behavioral schemata, particular events would be seen as instances of some kind.

In the same way, the evolution of kinds of covert linguistic behavior for arguments establishes labels for invoking certain kinds of reasons for drawing conclusions in certain kinds of situations. The difference is that in the linguistic case, the behavioral schemata can be generated, not only covertly, but also overtly as verbal behavior, and thus, the general conceptions can also be represented publicly as principles.

An implicit conception of efficient-cause connections would already have evolved with a primitive language of natural sentences. The covert nonverbal behavior of linguistic behavioral schemata also act on a worldview of states of affairs (using a mammalian map to refer to objects in space) to call up images of their effects and causes, and situations that could be handled in the same way would have led to the evolution behavioral schemata for constructing naturalistic images that established labels for the kinds of causes and effects involved in them. But without the use of psychological sentences, mere linguistic subjects were unable to represent states of affairs as causes, and the nature of the connection between causes and effects could be expressed only implicitly by their verbal behavior in certain social contexts.

Likewise, the evolution of linguistic schemata for using psychological sentences would give them a general understanding of rational causation, for neurological development would lead to labels for kinds of psychological images that have similar causes or effects.

With the evolution of psychological sentences, however, reflective subjects would also have an explicit concept of cause, for the ability to think about how they are using naturalistic or psychological images to represent the casual connections among states would enable them to represent causes as causes. Given their general understanding of causal connections, therefore, they could also represent principles about causation as principles about causation, either naturalistic or reflective. And since they could understand the causal roles of the psychological images being constructed by such talk, they could identify some propositions as premises or reasons for other propositions as conclusions, making the inferences they intend listeners to construct in their rational imaginations clear. Thus, rational subject could formulate general arguments about how to handle whole ranges of situations all at once and recognize that they are appealing to general principles.

The evolution of principles would make the arguments accumulated as culture more complex, because as we have seen, the arguments would come in groups and stand or fall together. That is, they could have a general theory about each fields of situations, and a single argument could affect a whole range of conclusions at once. Biological evolution has no parallel to the integration of arguments at the ecological level in cultural evolution.

The change of culture in the direction of maximum holistic power for arguments is, however, only a tendency in spiritual animals. It occurs only when arguments go through reproductive cycles, and spiritual animals differ in how completely and regularly linguistic interactions among the members embody that ontological cause.

The extent to which members look for differences in their world views and argue about them would probably be rather limited until spiritual animals evolved into civilizations. When whole classes of members were freed from urgent demands of controlling immediate conditions affecting their reproduction, there would be leisure to argue about issues that are not pressing, and when writing evolved, complex arguments could be preserved an passed on from one generation to the next. But even civilizations would not undergo much cultural evolution, unless their culture happened to value argument and independent judgment. Because of how behavioral schemata evolve by reinforcement selection in each brain, the natural tendency of reflective subjects born into spiritual animals is to believe what everyone else takes for granted and to pursue the goals that are generally valued. Considering the importance of mutual agreement in being able to coordinate the members and act as a spiritual animal, such disagreements might even be repressed, unless they could not be avoided for some reason. Indeed, such inhibitions may be so limiting that rational selection is little more than passing the language and social practices on to the next generation. And overcoming the herd instinct may require special genetic conditions as well as special cultural conditions. But when the right conditions did hold, and regular and sustained argument about the whole range of situations did take place, there would be an inevitable tendency of culture to evolve in the direction of natural perfection for arguments of their kind.

Far reaching cultural evolution is not as accidental as its dependency on such conditions makes it seem, because the spiritual animals in which this limited form of reproductive causation is contained are themselves evolving biologically at the social level. Spiritual animals are a form of life whose reproductive cycles add up in real space over time, and thus, they impose natural selection on themselves at the social level of biological organization. Since one of the conditions they must control is making correct decisions about war and peace, they are subject to a strong, group-level selection pressure, which would favor spiritual animals in which cultural evolved more quickly.

Considering the additional power that cultural evolution would afford them, it is clear that biological evolution would eventually favor spiritual animals that fostered the conditions for cultural evolution to occur. Or negatively, natural selection by warfare would work against spiritual animals whose cultures did not give their members as much opportunity to judge arguments by their coherence — or at least it would, if they were also unable to assimilate the discoveries that occurred in the cultures of other spiritual animals.

In the overall course of evolution, therefore, biological natural selection at the social level would eventually shapes the social, cultural and biological mechanisms sustaining the rational selection of arguments, so that the cultures of spiritual animals generally would tend to change in the direction of maximum holistic power for arguments of their kind, that is, would tend to discover the true, the good and the beautiful.

Natural perfection of rational level culture and its dichotomies.S

ince cultural evolution at the rational spiritual stage is inevitably part of the overall course of evolution, there is a point in its overall course at which evolution speeds up enormously, for the power of spiritual animals increases more rapidly by cultural evolution than is possible by biological evolution alone. There are, however, additional necessary truths about the evolution of rational level culture. Our ontological derivation of the course of evolution includes implications about the content of culture, implying that limits are inevitably imposed on cultural evolution at the rational spiritual stage by dichotomies that cannot be overcome, except by religion.

Even when cultural evolution is not limited by lack of resources, leisure or cultural inhibitions, there is a limit to how far the culture of reflective spiritual animals can evolve. Though rational culture gradually evolves in the direction of natural perfection for arguments of its kind, their maximum holistic power is not as great as it would become at the next stage of spiritual evolution (the philosophical stage, with arguments organized on a higher level of part-whole complexity).

It might seem that all the arguments accumulated as culture would ultimately be combined as a single argument, since cultural evolution is change in the direction of arguments that are integrated and harmonized with one another according to general principles. But it is not possible to show how all the various conclusions for specific situations derive from the same basic principles as long as arguments are limited to the kind made possible by reflection on the causes of beliefs and behavior, that is, the kinds of reasons that subjects consider at the rational spiritual stage.

Three dichotomies are built so deeply into the nature of reason that rational selection cannot find a principle, or usually even a well integrated set of principles, that can bridge the gaps between these clusters of arguments and explain how they are related to one another.

One dichotomy is the difference between arguments about what to believe and what to do, that is, between theoretical and practical reason.

Another dichotomy arises within theoretical reason, between arguments concerning what to believe about objects in space and arguments concerning what to believe about subjects, that is, between naturalistic and reflective understanding.

The final dichotomy arises within practical reason, between arguments about what the individual ought to do and what the spiritual animal ought to do, that is, between individual (self) interest and spiritual (self) interest.

These dichotomies are an inevitable incoherence about rational culture. This limitation may not be felt until rational level culture approaches natural perfection for arguments of its kind, because until then, it may be obscured by other forms of incoherence. And when these dichotomies are seen as problems, they may be papered over by religion. Indeed, it may not be possible to recognize them for what they are until the next spiritual stage of evolution, when the validity of rational level arguments is what arguments are about.

What is lacking in rational level culture is, as we shall see, the concept of reason. Reflective subjects have reasons for their conclusions, but they do not have a theory about the nature of reason by which to fit all those arguments together as a single argument, and thus, the only way they can integrate different arguments is by the discovery of principles that apply to them. At the next stage, theories about the nature of reason will give epistemological philosophers a foundation from which to construct arguments about the validity of the arguments of rational level culture.

Before taking up the philosophical spiritual stage, however, I will use these three dichotomies as a way of surveying the content of culture at the rational spiritual stage as it approaches natural perfection. The three dichotomies are necessary truths of ontological philosophy, because we can see, from ontological foundation, that even at the end of cultural evolution at the rational spiritual stage, arguments will be divided into four irreducibly different clusters by these three inevitable differences among the kinds of arguments that evolve in rational level culture.

Theoretical and practical reason. As

we have seen, culture includes two different kinds of arguments, arguments about what to believe, which are based on beliefs and perception, and arguments about what to do, which are based on desires and beliefs. The former arguments make up theoretical reason, whereas the latter make up practical reason. The interest of reason in the former case is discovering the true, whereas the interest of reason in the latter case is discovering the good (though as we have seen, it ultimately depends, in both cases, on discovering the beautiful).

The difference between theoretical and practical reason is inevitable, as we can see from the vantage of ontological philosophy, because reason is a kind of animal behavior guidance system. Since animal behavior, unlike mere biological behavior, acts on objects in space, it must be adapted to the immediate situation, and so input is used in two different ways to guide output. It is used to gather information about the world so that it can generate behavior that is adapted to the situation, and it is used to choose what kind of behavior to generate in each situation. This difference has been explicit from the telesensory stage of evolution, as the following diagram indicates.

Practical arguments have to do with the kind of output, but the input about the world that is used to choose the kind of behavior in each situation and to generate whatever kind of behavior is selected is supplied by theoretical arguments. That is, beliefs are supplied by the animal system of representation, and desires are supplied by the goal selection system. But as we have seen, the animal system of representation evolves through a series of stages of increasing power, adding one new form of imagination after another, until it is able to understand not only spatial, structural and efficient causation, but also rational causation. Reflection makes it possible to understand not only the role of perception in the formation of beliefs, but also the role of desire along with belief in causing behavior, and as we have seen, when such causes are represented as causes as part of the very process of causing behavior, they become reasons. Thus, there are two kinds of reasoning, theoretical and practical.

In addition to entailing a difference between them, ontological philosophy also implies, as mentioned earlier, that holistic power is maximum for theoretical reason when its conclusions are true and that holistic power is maximum for practical reason when its intentions are good.

Truth is correspondence to what is, and since such a correspondence is built into the very structure of imagination, culture must evolve in the direction of discovering the true as arguments are selected for making world views maximally coherent. That is, the relations of objects in space and how they change by motion are adequately understood by spatial imagination, the geometrical structures of objects in space and their effects on interactions are adequately understood by structural imagination, and the states of objects in space and their efficient-cause connections are adequately understood by naturalistic imagination. Furthermore, the psychological states of subjects in space and their rational-cause connections are adequately understood with the evolution of rational imagination, with reflective understanding. All these forms of imagination are built into rational imagination, and the correspondence between rational imagination and these aspects of the world means that worldviews that are more coherent in rational imagination are more likely to correspond to what actually exists, and thus, the cultural evolution of theoretical arguments tends to discover the true about the world.

Though rational subject are naïve realists, who do not recognize that perception is mediated by sensory images, they understand the correspondence involved in truth well enough to pursue it. They think of it as the correspondence between the naturalistic images constructed as the meanings of natural sentences with perceptions as the natural world (or the correspondence between the psychological images constructed as the meanings of psychological sentences with ill-understood states of subjects who are perceived as objects in space).

Animal behavior in general is guided to attain goals that control conditions that affect reproduction, and since evolution is in the direction of maximum holistic power for organisms of its kind, that is, their natural perfection, the primary goal of practical reason is to do what contributes most to the natural perfection of organisms of its kind. The goals to be pursued are determined by desires, both those that are built into the animal behavior guidance system by the biological behavior guidance system and those that are learned from experience, and with the evolution of reflection, it is possible to plan behavior in many different situations over long periods of time that will maximize the satisfaction of those desires.

Since intentions are good when they make a necessary contribution to natural perfection, we can see how the cultural evolution of practical arguments tends to discover what is good. As part of their worldview, subjects would have (and usually share) intentions about what to choose in the whole range of situations they face, or what might be called “values.” Insofar as an argument for doing something fits the intention comfortably together with those intentions, its acceptance would depend on the goals it would attain or the desires it would satisfy. But in order to change a fixed intention about how to deal with certain situations, such as a custom or general value, practical arguments would have to displace the reasons for accepted practices. But since such practical arguments would be judged by their coherence with all the intentions included in their worldview, it would tend to discover the good (or at least avoid certain mistakes), because it would be part of a plan for attaining all their goals.

Practical arguments would not be limited to arguments about what to do in particular situations, any more than theoretical arguments are. Culture would tend to evolve principles of practical reasoning as well as principles of theoretical reasons, and for the same reason — because of the way imagination works and how behavioral schemata evolve in them by reinforcement selection. Some situations requiring decisions about what to do would be similar, involving similar choices among means to some goal or similar choices among alternative goals, and since the arguments about what to do would also be similar, behavioral schemata for arguments would evolve that handle them all in the same way. And those behavioral schemata could be expressed in overt verbal behavior, as practical principles.

Such reasoning implicitly involves aesthetic judgments, since it is looking for the best complete set of intentions by comparing such sets in rational imagination, and thus, the good implicitly appears as what would contribute to their own natural perfection. But since rational intuition enables such subjects to recognize natural perfection about other aspects of the world, they can also see what would be good in other ways, for example, what would be good for other kinds of animals, for plants, or for the ecology, and thus, they can also conclude that it is also good to pursue those goals. The pursuit of such optional goals is just an aspect of the autonomy of reason, and we will consider later how it contributes to natural perfection.

None of this is obvious, however, from the point of view of reflective subjects, at least, not at the rational spiritual stage of evolution. Though it is obvious there is a difference between theoretical and practical reasoning, it is not clear how the true and the good are related to one another. Indeed, the difference is not commonly described as a dichotomy between facts and values in rational level culture. And it is not clear how goodness is even part of the world.

Rational subjects find themselves having an interest in both the true and the good, and they naturally understand truth as correspondence to the world. But it is not clear what kind of correspondence is involved in goodness, if any. Attempts to explain what is good as deriving from ancestors, gods or other religious myths do not stand up to criticism, because they are merely arguments for submitting to the judgment of other such reflective subjects without explaining why their judgment is correct.

Desires are seen as goals from the point of view of the reflective subject. But even when goals are recognized as being caused by desires, that does not explain why they are good, because there is still no explanation of why they have those desires. It may be obvious that having certain desires contributes to survival, as hunger does by moving one to acquire energy and fear does by motivating self protection, but it remains a mystery why surviving is good. It seems that since they have goals, there must be some overarching goal to which all the others are means, but there are different ways of identifying that goal. And no way to explain why we should have an ultimate goal.

In rational level culture, these limits to their understanding of the nature of goodness are generally recognized, because there is usually a set of religious beliefs that can be used to justify their conclusions, and the frailty of religious explanations does not become apparent until different cultures come into contact. The effect of that will be considered in discussing the next spiritual stage.

Naturalistic and reflective understanding. Theoretical reason is based on a faculty of imagination that is able to understand two fundamentally different kinds of causes, efficient causes in the natural world and rational causes of the behavior of subjects, and as a result, rational subjects are amphibians, living in two worlds at once. They live as animal bodies in a world of objects in space whose states of affairs are causally related, and they live in a world of subjects in space whose psychological states play various roles in causing behavior (and beliefs). The natural and social worlds are both worlds of facts about particulars, but since principles evolve as parts of the evolution of culture by rational selection, one leads to a science of nature (or natural science) and the other leads to a science of subjects, including both individuals (or psychology) and how subjects live together as parts of spiritual animals (or social science).

Understanding of the natural world is based on spatial and structural imagination and how the regularities represented are used (along with others that are simply discovered by experience) to represent causal connections in the world of objects in space. The causes are efficient causes, and the relevant regularities enables them to make inferences about what to believe (and what to do).

Similarly, understanding of the social world is based on rational imagination, which is made possible by the use of psychological sentences. Reflection uses the regularities about the behavior guiding process in one’s own brain to simulate the processes going on in the brains of others, and since those causes are represented as causes in the very process of causing behavior, they explain and predict behavior in terms of reasons.

“Reflective understanding” is a way of referring to the use of rational imagination to understand the causes of subjective behavior, that is, rational causation, and it is meant contrast to “naturalistic understanding,” as the use of rational imagination to understand efficient causes in the (rest of the) natural world.

The objects that are explained in these basically different ways are all located in space, but since the relevant facts are so different from one another, the social world appears from the point of view of the reflective subject to be superimposed on the natural world. And though our ontological perspective explains the relationship between them and shows why both are inevitable, none of this can be understood by reflective subjects at the rational stage.

It is obvious that individuals have bodies that move around in a world of objects in space and that those bodies are moved by choices made on the basis of beliefs and desires, like their own. Subjects are as much a part of their world as other objects in space, but they seem basically different, because subjects cannot be explained by efficient causes in the same way.

Nor would the nature of subjects be explained, if it were recognized that what makes rational explanation possible is simulating the other’s inferences in one’s own rational imagination, because rational imagination is not itself explained in terms of natural processes, but must be accepted as basic. Thus, even though it may be obvious that rational subjects can see into one another minds and even that the social world is constituted by their mutually accepting certain practices and arguments, the gap between the natural and social world cannot be bridged at the rational stage. They seem as different as body and mind. The cultural evolution of arguments about each leads fundamentally different sciences.

Naturalistic understanding. There is not much more to be said about the evolution of natural science at the rational stage, because without the use of mathematics, its principles cannot probe much deeper than the basic regularities represented in imagination and regularities discovered by the perception of the natural world.

Theoretical arguments become more powerful as more alternatives are considered, because when only the most coherent are selected, the conclusions tend to correspond to the world. Beliefs are caused by perceptions, and they must continue to stand up to perceptions. But they represent states of affairs that are also causally related, and since the most basic of those causal relations are represented by the structure of rational imagination, beliefs are also tested by how they fit together as parts of a worldview. That is, when a new conclusion about what to believe is considered, it is judged by its correspondence to the world as represented in that worldview. The reasons for it must show that it is more likely to correspond to the world than whatever belief on the topic is currently held. As long as that judgment is not clear, argument will tend to persist. But when each individual judges what is true by which argument leads to the most rationally coherent worldview, the arguments generally accepted in a spiritual animal tend to discover the true.

Arguments about what is perceived in nature leads to the recognition of regularities, or causal connections, which are used in controlling relevant conditions. In the complex natural perfection of the biological world produced by reproductive causation, the discovery of regularities can be a source of great power, for example, in tracking animals, identifying plants as foods, discovering medicines for various ailments, and later in the technology used in agriculture, constructing cities, building ships, commerce, and the like.

The ability to probe beneath the level of observation and discover the natures of smaller parts of objects and the structural causes they make up is limited by the nature of perception. We have seen what they are in a spatiomaterial world like ours, but we have had the advantage of the discoveries of modern natural science. They come from using mathematics to keep careful track of the quantities involved in such micro level processes. But the evolution of mathematical arguments depends, as we shall see, on a more radical random variation in arguments which is made possible only at the next stage of evolution. Rational level culture includes, at most, the basic principles of arithmetic and geometry, and they are not recognized to be different from other regularities.

At the rational stage, therefore, natural science tends to fade into magic and mysticism. What cannot be explained by the sorts of efficient causes discovered by natural science can seem to be explained by supposing that events are caused by “spirits” or “souls” in nature that act intentionally for certain reasons. Thus, technology based on natural science gives way, at the limits of its power, to magic based on animism or the belief in gods. But this is merely to fill the gaps in understanding nature with explanations based on their understanding of subjects, though the incoherence of such explanations may not even be suspected, since there is no available alternative.

Reflective understanding. Reflective understanding includes everything known by rational subjects through their capacity to explain behavior rationally, and since this cognitive capacity evolves in spiritual animals, it covers both individuals and the spiritual animal itself. But just as natural science at the rational stage is limited by the nature of perception, so social science at the rational level is limited by the nature of reflection. On the one hand, psychology cannot see any deeper into the nature of individual reflective subjects than the reasons that are used to explain their beliefs and behavior, and on the other hand, social science cannot see any deeper into the nature of their public social world than what is obvious to each member in generating institutions as social level behavior.

Reflective understanding of individuals (psychology). Since individual beliefs and behavior are explained by reasons, the science of subjects is little more than the power of reason, whose essential nature is entailed as part of the course of evolution by reproductive causation.

Reason is now commonly called “folk psychology,” on the assumption that the connection between reasons and the behavior they cause is recognized by learning the laws of nature discovered by psychology as a primitive branch of natural science which happens to be built into culture. But the laws of folk psychology are not regularities about behavior discovered by perception, like natural laws. They are, rather, built into the structure of rational imagination.

Nor is this capacity to explain subjective behavior a so-called “Theory of Mind” that is built into the brain genetically as a special “module” on the now fashionable modular theory of how the brain works (The modular theory hold that the brain is made up of various independent modules that have evolved separately by natural selection for causing beliefs and behavior in various relevant situations, such as beliefs about colors, numbers, kinds of animals, and generating athletic behavior, social behavior, musical behavior, verbal behavior, artistic behavior and the like). Instead, in explaining beliefs and behavior rationally, the brain uses its own behavior guiding processes to simulate the behavior guiding processes in other subject. The foundation of reason is, as we have seen, a higher level of neurological organization in the faculty of imagination, and thus, it incorporates all the more elementary forms of imagination and verbal behavior.

Since reason uses the brain’s own behavior guiding processes to simulate the behavior guiding process in another subject, it may seem that the principles of rational explanation are all fixed by the nature of the behavior guiding mechanisms built into the brain. That is, as arguments of their science of subjects evolve by rational selection, spiritual animals all discover the same principles for explaining behavior rationally. However, some principles for explaining the behavior of rational subjects are discovered empirically in a way that parallels the discovery of laws of natural science, because mechanisms built into the brain do not already represent directly one of the most basic causes of behavior. And this makes it possible for cultures to differ in their science of individual subjects.

Perceptions and beliefs about nature can easily be made objects of reflection, because their contents are already represented by naturalistic images in the rational imagination of the animal system of representation. But the content of desire, that is, its object, is not already represented, because desires are merely dispositions to behave in certain ways toward certain objects. They are fixed, in a sense, because they are ultimately imposed by the biological behavior guidance system. But they need to be discovered empirically, and the cultures of different spiritual animals may vary in how far their theories about basic desires have evolved.

The kinds of desires can be identified only by the kinds of behavior they tend to cause, that is, in terms of the goals at which they are directed and by which they are satisfied. Some desires, such as the animal desires for food, water, sleep, sex, safety from predators, and the like, are fairly obvious, but others are not, such as social desires, which are attached to other subjects in the group or to one’s relationship to them. Fantasies about behaving in certain ways and the states brought about by them are not reliable indicators of their goals, for there may be different ways of describing those states. (Even the history of past reinforcement for the behavior make not clarify the goal, because it is not always obvious which desire is responsible for the reinforcement.)

Thus, some desires are identified only by principles of the culture’s science of subjects. Though their identity may be revealed by the evolution of principles for explaining behavior, this part of social science is not always a purely theoretical science, because individuals see their desires as the goals at which behavior is directed and arguments about which goals to pursue are part of culture. Thus, psychology merges with practical reason, and cultures differ in the desires they use to explain behavior because they have different intentions for handling the situations that arise.

The disagreements between cultures about such principles of reasoning does not necessarily imply that some are true and others false, because the science of individual subjects is reflective. It is used by subjects to understand themselves, and the principles they use to explain themselves helps constitute the kind of subjects they are. They come to think of themselves as being moved by desire of the kinds recognized in their culture and, as a result, become reflective subjects of that kind. It is part of the “self.”

The nature of the Self. The evolution of arguments about why individuals behave (and believe) as they do is not just a science of subjects, or psychological science, because it helps constitute the very objects it describes. Individuals enter a spiritual animal as particular, infants with no role except as objects being handled by their parents (or other adults), but as they mature, they acquire the language being used, learn the practices and accumulated arguments of their culture, and eventually become reflective subjects who are members of society and make choices about how to live their lives. As he uses the arguments accumulated as reflective understanding of individuals, the individual subject comes to have a Self.

Self-reflection is possible, as we have seen, because psychological images can be used to think about one’s own psychological states. Rational imagination enables the subject to see her own psychological states as causes of her own conclusions about what to do or what to believe, and using it reflexively, that is, to reflect on herself, is what transforms causes of behavior into reasons. It means that representing the causes of her behavior as causes of behavior is normally part of the very process of causing it. Thus, not only can reflective subjects describe their own behavior in terms of the desires and beliefs that cause it, but they can also explain their past behavior by such reasons and choose what they will do by considering the reasons for different alternatives. The coherence of this reasoning about individual reflective subjects is based on the assumption that the subject is identical over time, and thus, as the reflective subject learns the culture’s science of subjects, she recognizes that she is identical over time. That is what gives her a Self.

A non-reflective animal may also be said to recognize its identity over time, but that does not give it a Self. The brutish animal understands itself as a body in a world of objects in space, and the coherence of that understanding is built on the assumption that the present body is the same body that has acted in the past and will act in the future. Even in thinking about the structure of space, the animal subject takes its covert locomotion to be the behavior of the same body that explored the territory in the first place. But not only is this identity merely implicit, it is also merely the identity of a body. The non-reflective subject lack the concept of a subject, and thus, it cannot recognize its identity over time as a subject, not even implicitly.

Self-reflection is exhibited in the subject’s capacity to tell a story about himself that explains why he acted as he did in the past, explains how its effects on the world produced new situations in which one had to act, and so on, until it is clear how the present situation arose and he is telling his story. That story about his past is the context in which one chooses what to do in the present situation, and he sees his present choice as the continuation of the same story, recognizing that he is the same subject who will tell such a story in the future about making this choice. That is an explicit representation of his identity over time. He refers to the subject who acted in his past and who will act in the future as himself. That ability is what gives the subject a Self.

Stories about reflective subjects are one of the kinds of arguments that have evolved in the culture, a kind that depends on rational imagination in its role as reflective understanding and its concept of a subject. One acquires the capacity to tell stories about people as a part of neurological development, that is, the evolution of behavioral schemata by reinforcement selection that internalizes the language and culture of the spiritual animal. The individual learns to tell a story about himself by hearing others tell stories about them, or stories about themselves, or about third persons. It requires a memory for past events, including his past thoughts and statements, and though that may require an increase in the size of memory, it needs only the same basic mechanism for linking images in sequences that underlies all forms of imagination. But it also requires a culture in which the arguments by which individuals can tell stories about themselves have evolved, and no one can learn how to tie the events of his life together as a story about himself without learning to see other subjects as having stories to tell about their lives. The subject has a Self only when he also recognizes other reflective subjects as also having Selves.

To speak of subjects as “having a Self” leaves unexplained what the Self is. Indeed, there is an ambiguity about the term “self” as it is ordinarily used, because it can be understood as referring either to the immediate subject who leads the life or to the life that is led. The first might be called the self that one is, and the second is the self one has. But I will refer to the former as the reflective subject (or rational subject), and continue to refer to the latter as the “Self”. The current philosophical puzzles about the nature of personal identity mentioned above arise from trying to understand the nature of the Self from the point of view of the reflective subject, and they can be solved by ontological philosophy.

Being constituted by a kind of reasoning that is based on the assumption that the subject is identical over time, the Self differs from the subject as the whole life differs from the present moment in that life. That is, the Self includes the whole life, from beginning to end, for it includes the whole cycle of reproduction, the same four dimensional “substance” that is the derivative ontological cause of reproductive global regularities. But the Self is something that comes into existence in the world for the first time at the rational spiritual stage. The Self is constituted by the explicit representation of oneself as being identical over the whole span of one’s life, because that gives one’s life a kind of wholeness that it would lack without it. Non-reflective animals, including subjects with only the use of natural sentences, live only in the present moment. Though they can see the current situation against the background of memories of what has happened to their bodies in the past and experience is enriched by imagination about what might happen in the future, they still act on the strongest desire at the moment. Their attention never strays beyond the problem of satisfying whichever desire is moving it. But self-reflection changes that, because the reflective subject acts from an awareness of his identity over time. Having a Self, as we shall see, increases his power enormously.

Though subjects are seen as having Selves, the ontology of the Self is not generally obvious from the point of view of the subject at the rational stage, because one sees one’s own Self on the model of the Selves of other reflective subjects in the society. Self-reflection involves basically the same kinds of argument that are used to understand other members of the society, and comparisons are inevitable. What stands out, therefore, are the differences in the kinds of Selves individuals have, which are described in terms of their character or personality. They are thought to be temperate, courageous, generous, cautions, creative or the like, as if the life one leads were an expression of some inner disposition, rather than as something that each individual creates in leading his life.

The arguments of a culture’s science of subjects portray individual as having Selves of certain kinds in explaining their behavior. And the kinds of Selves individuals are thought to have are generally limited to those that are possible, given the theory about the basic desires (or goals) that individual have that is included in its science of subjects. But since reflective subjects born into the spiritual animal internalize its culture, its arguments about how to explain beliefs and behavior become the foundation for their understanding of who they are, and thus, they come to think of themselves as having Selves that are moved by desires of those kinds. Thus, the science of subjects that evolves at the rational spiritual stages helps constitute the very object that it explains, and it is a self-fulfilling truth in certain ways.

Though the Self is constituted by the recognition of the identity of the subject over time, there is more to the Self than simply that continuity, because the Self is also necessarily part of a spiritual animal. To have a self is, therefore, to have a spiritual nature, and that is important, as we shall see when we take up practical reason. But as far as theoretical reason is concerned, that aspect of the Self is explained by arguments about the social world.

Reflective understanding of the social world (Social science). The social world is how the spiritual animal appears to the reflective subject who is a part of it. Thus, it depends on the nature of spiritual animal, which is entailed as part of the inevitable course of evolution as explained from the foundation of spatiomaterialism. That is not, of course, how it appears at the rational spiritual stage, because social science evolves from arguments exchanged by members of spiritual animals. Social science is the view of the spiritual animal from inside.

There are necessary truths about social science, because this ontological explanation of spiritual animals has implications about the arguments about the social world that evolve within spiritual animals.

To call those arguments “social science” is to use that term in a broad sense, because it includes knowledge of particular facts about the social world, not just the principles that evolve to unify the arguments about them.

But that is the relevant sense, because both kinds of truths are radically different from the truths discovered by natural science. Unlike the world known by natural science, which exists independently of the reflective subjects who argue about it, the world known by social science depends for its existence on reflective subjects generally accepting the arguments about it. There is a sense, therefore, in which theories in social science are self-fulfilling truths.

The content of social science has to do mainly with institutions, for they are what give the social world its structure (beyond what is essential to spiritual animals) and provide the context for the particular events that make up the history of a spiritual animal. I will begin, therefore, by describing the basic nature of institutions, for that explains the nature of the correspondence by which social science is true. Then, after inventorying the basic kinds of institutions, I will consider how institutions fit together under both the social and the cultural aspect of spiritual animals.

The nature of institutions. Institutions have a nature that can be explained as an elaboration of the plan distributed by a leader at the primitive spiritual stage of evolution, because institutions are basically a form of social level behavior, that is, an action of the spiritual animal as a whole. Since animal behavior acts on objects in space, its power ultimately comes from how it structures the thermodynamic flow of matter from free energy to evenly distributed heat like a geometrical structure in the region to bring about conditions that enable it to reproduce. But in the case of spiritual animals, that behavior is generated by using language to coordinate the behavior of its members. At the primitive spiritual stage, such coordination is a result of the leader distributing a plan of social level behavior to the members and their following it. What is different about rational spiritual animals is that the role of the “plan” in coordinating behavior is played mainly by rules that are mutually recognized by members and generally accepted as reasons for their behavior in the situations covered, that is, by rule-following.

An institution of a spiritual animal is described in its culture as a set of social roles. Such social roles are governed by rules that determine which members occupy them and that give their occupants certain rights and duties in relation to the occupants of other social roles. Taken together, therefore, such rules are a system. But the existence of institutions depends on the members generally following the rules, not merely knowing them. That is, particular individuals must occupy the roles (or most of them), and they must interact with one another according to the rules governing their social roles.

Institutions are, therefore, generated by a decentralized, ongoing way of coordinating the behavior of members. The evolution of a language with psychological sentence is what makes it possible, because such rules are basically the general acceptance of a set of arguments about how certain members should behave in certain situations. Mutual acknowledgement of the rules is a reason for doing what they prescribe, and when they are being followed, members occupy social roles defined by the rules. For example, one must provide food for the child because he is its parent, or one must do what another member says because he is the leader and has the authority to rule on such matters.

The rules governing social roles are not arbitrary, but are understood as guiding their behavior for certain purposes, much as the leader’s plan at the primitive spiritual stage. We shall consider the functions of institutions shortly. But since behavior in social roles is directed at certain goals, it is possible to argue about the rules governing them, and thus, these arguments tend to evolve by rational selection in the direction of intentions that are good in the sense of contributing to the natural perfection of the spiritual animal by controlling conditions that affect its reproduction. There are, therefore, principles by which social roles in institutions are justified and explained, and the set of rules becomes increasingly coherent as a whole.

For each institution of a spiritual animal, therefore, its culture contains a “theory” describing the social roles that make it up and the rights and duties incumbent on its occupants. It is a theory about the social world, albeit a low level theory, and, thus, a part of social science in the broad sense. It may be inaccurate, if members are not actually following the rules. But insofar as the relevant linguistic representations correspond to what members occupying the social roles do, they are true.

The truth of such theories about the social world is basically different from theories is natural science, because a correspondence of its theories to what exists in the world is part of the behavior guiding mechanism that generates the institution as social level behavior. Thus, theories of social science are self-fulfilling in a way that theories of natural science never are. The truth of theories in natural science depends on how the world is independently of what reflective subjects believe, and its workings may not be open to them. But the dependence of the social world on what reflective subjects believe about it is not problematic in that way. Institutions are the spiritual animal’s social level behavior, and such theories about them are as much arguments of practical reason as they arguments of theoretical reason.

The correspondence between the beliefs about the social world and the social world itself also involves a part-whole relation that is different from theories in natural science. The object represented by such social theories is the behavior of the spiritual animal of which the members are parts. The rules defining social roles are the “plan” in the minds of the members by which their behavior is coordinated, and just as each member must identify with a different task in the common plan in order for the plan to coordinate their behavior, so each member who participates in an institution must occupy some social role in relation to the social roles that make up the institutions. Thus, the way that such social theories must be true in order for the social world they describe to exist involves a correspondence in which each individual identifies himself with a certain social role in that institution.

Though it is possible to construct linguistic representations describing the social world that do not depend on the point of view of any particular individual, that is not necessary for the institution to exist, because detailed knowledge about certain social roles may be limited to those members who occupy them or whose social roles are closely related to them. In other words, it is possible for culture to be complete in the brain of each member, but that is not always necessary for the culture to generate institutions as social level behavior.

Though the existence of the social world depends on the cultural aspect of the spiritual animal containing a theory about it, that does not make the social world less objective than natural science. Institutions exist independently of any particular member, because they are the behavior of the spiritual animal as a whole. The institution exists as long as the behavior of enough members is coordinated by mutually accepting the arguments about social roles. Thus, the social world can constrain the individual in much the same way as the natural world.

This is what Giddens (1976) calls the “duality of structure.” Even though institutions, being constituted by the mutual acceptance of beliefs about social roles, do not exist in the way that nature does, they do constrain individual behavior just as surely as nature does.

There is nothing paradoxical about the effect of institutions on individual members when the they are seen as social level behavior, because they are simply something that the spiritual animal does to its members in much the same way as it acts as a whole on other objects in space. They are forms of social level behavior. Thus, individuals may be coerced into performing their social roles by the threat of punishment, either by other members whose social roles authorize them to act for the spiritual animal in that way or, informally, by earning a bad reputation among the members of a spiritual animal.

The constraints imposed by the enforcement of institutions should be distinguished from another way that spiritual animals affect their members. The members internalized the arguments of their culture as they grow up, and their acceptance of those arguments helps constitute the social world in which they find themselves, for they go around thinking of other subjects as occupying social roles and obeying the rule of their own social roles in relation to them. But enculturation is basically liberating. Once members develop rational imagination by internalizing the language of their spiritual animal, they can participate in the exchange of arguments, and that provides the only effective way to change the social world. The rules about social roles whose mutual acceptance generates institutions are basically practical arguments, and since they can evolve by rational selection, the social world can, in principle, be changed by arguments that convince others to follow new rules. That is the other side of the “duality” of social structure.

Kinds of institutions. Institutions are not arbitrary. As we have seen, even the individuals who fill the roles that constitute them would explain their behavior by citing rules and explain those rules by principles that appeal ultimately to functions that are thought to institutions to serve. Thus, not only their nature, but also the kinds of institutions can be understood by reflection. Though the arguments that accumulate as social science tend to discover what is true about institutions, this knowledge is limited by being founded on reflective understanding, and we have a deeper explanation of their essential nature from our ontological explanation of spiritual animals as what evolves at a certain stage of evolution by reproductive causation.

Spiritual animals are the new kind of animal at the social level made possible by the use of language. The evolution of psychological sentences at the rational stage makes reason its behavior guidance system, and as we have seen, the evolution of arguments by rational selection makes reason increasingly powerful at guiding behavior. But since spiritual animals are a kind of animal, it is possible to infer the basic goals of its behavior. And since institutions are its social level behavior, that makes it possible to infer the basic kinds of institutions.

As we have seen, however, spiritual animals are different from multicellular animals in at least two ways. Reason is unique in serving as both the animal and the biological behavior guidance system of the spiritual animal, and the evolution of war means that its animal behavior at the social level must pursue a new kind of goal. These unique features should show up in the kinds of institutions that exist.

Stages of evolution are caused by level of part-whole complexity in the material structures going through reproductive cycles, and at each stage of evolution after the life begins, a biological behavior guidance system leads the material structures through reproductive cycles by coordinating the behavior of reproducing organisms that evolved at the previous stage. Until the social level of biological organization, that coordination was responsible for constructing the structural cause that would serve as the new kind of animal behavior guidance system at its level. But in the case of spiritual animals, the biological and animal behavior guidance systems are the same. Not only does language coordinate the behavior of multicellular animals so that they can go through reproductive cycles as a whole at the social level, but it also coordinates them in acting as a whole on other objects in space, like a social level animal.

Like any living organism going through cycles of reproduction, spiritual animal impose natural selection on themselves by the scarcity caused by their own population increase. (That is the grounds for thinking of them as a new form of life.) But the range of animal behavior that is possible for spiritual animals includes a means of controlling the main condition affecting their reproduction that was not available to animals at lower levels of biological organization. When resources become scarce, spiritual animals are able to acquire the free energy they need as animals by waging war against other spiritual animal. Hence, the spiritual animal behavior guidance system has to make a new kind of choice about how to behave. Making reliable choices about war and peace is the function that made the evolution of reason inevitable, and rational spiritual animals never escape the responsibility for making choices about war and peace.

Since social institutions are simply regular, ongoing forms of its social level behavior, the kinds of institutions can be explained by analogy to animals at the multicellular level, including the function of their biological as well as their animal behavior guidance system and except for the adaptation to war.

Kinship system. Spiritual animals do not need a mechanism of embryological development to construct each new generation from a fertilized egg cells, as multicellular animals do, because they reproduce by division. But their reproduction, as well as their continued existence, does depend on the sexual reproduction of its members, and that requires an institution to serve the functions of a mechanism of embryological development. This function is served by the kinship system.

Just as the cells introduced by asexual reproduction must have a location in the multicellular body and be determined to behave in a certain ways, so individuals born into a spiritual animal must have a location in its spiritual body and be determine to behave in certain ways. The social roles of the kinship system gives new members a location in the institutional structure of the spiritual animal.

But since the members reproduce sexually, they are more powerful when they avoid inbreeding, and thus, the kinships system must regulate marriages, including arrangements for marrying outside the spiritual animal, when they are sill nomadic bands.

Educational and religious institutions. Members normally accept the arguments of their culture and submit to reason as a result of development. But new members born into the spiritual animal must acquire the culture, including its language, social roles, technology, religion and other shared beliefs about the world, and that is the function of educational and religious institutions in spiritual animals. When these institutions serve their function well, members conform to the social roles they occupy, obey the laws and cooperate in generating the social level behavior of the spiritual animal.

The closest analogue to institutions of enculturation at the multicellular level are the endocrine system and the parasympathetic nervous system. The endocrine system is the ongoing activity of the multicellular biological behavior guidance system, and the parasympathetic nervous system coordinates the multicellular biological and animal behavior guidance systems. The coordination of the behavior of cells by these systems is what makes it possible for motor commands issued by the brain to control the muscles in appropriate parts of the body, in much the same way that enculturation by educational and religious makes it possible for the spiritual animal to act as a whole by coordinating the behavior of members through acts of government or other institutions.

Judicial institutions. Though members normally accept the arguments of their culture, conform to the social roles they occupy and obey its laws, the power of the spiritual animal to act is curtailed, when individuals fail to do what their social roles require of them. Thus, one of the goals of its social level behavior is to punish members for wrongdoing. That requires some sort of judicial institution, because cases of wrongdoing involves conflicts among the members which must be resolved.

The analogue of the judicial institution at the multicellular level is the animal’s immune system. Just as the judicial system tracks down and punishes outlaws, so the immune system tracks down an destroys pathogens and its own cells that misbehave in certain ways.

Given the autonomy of rational subjects, killing members is not the only way of serving this function in spiritual animals. Since wrongdoing is a failure to conform to the practical arguments accumulated in the culture, compliance can often be punishment. Submitting to reason comes from a desire that derives, as we have seen, from the desire to submit to the leader at the primitive spiritual stage and, earlier, from the desire to submit to higher animal in the dominance hierarchy. Thus, since the desire to submit in the dominance hierarchy is established and strengthened by a confrontation in which the individual is forced to submit, the desire to submit to reason can be strengthened in many cases by a ceremony that forces the individual to submit to the spiritual animal. That ceremony is punishment.

Political institutions. Animal behavior requires a behavior guidance system to select and generate behavior in relation to other objects in space. This function is served by the brain in multicellular animals, and though it is ultimately served by reason in spiritual animal, special institutions evolve to make urgent choices in immediate situations. The role of a leader in primitive spiritual animals evolves into a governmental institution at the rational spiritual stage, with the authority to make decisions for the spiritual animal.

In order to make decisions about war, spiritual animals may cooperate with other spiritual animals that are friendly, and thus, government may include diplomatic institutions.

There may also be decisions that have to be made about the economic behavior of the spiritual animal as a whole, including not only provisions for its army, but also decisions about how to deal with natural disasters. And in more populous spiritual animals, more extensive coordination may be needed for large scale projects, such as building roads and irrigation systems.

In addition to guiding the behavior of the spiritual animal in relation to other objects in space, political institutions would normally also have responsibility for the reproduction of the spiritual animal, such as dividing nomadic bands, setting up colonies, and waging wars to establish colonies in new territories.

Economic institutions. The basic goal of animal behavior is acquiring free energy from other objects in space by ingesting them, that is, feeding. In spiritual animals, this kind of behavior originally took the form of hunting and gathering, but at later stages, as we shall see, it comes to involve agriculture and extracting all kinds of useful objects from nature. The need to acquire free energy from nature is never overcome, but at later stages of spiritual evolution, more and more free energy is acquired in forms that is used directly to control relevant conditions, such as the control of fire, the use of beasts of burden, and as fuel for machines.

And just as multicellular animals require a biological behavior guidance system to set up organs for digestion as well as ingesting other objects, so cultural evolution leads spiritual animals to acquire economic institutions that use what is taken from nature to produce objects that are useful in attaining goals.

Moreover, just as the usefulness of free energy acquired to multicellular animals depends on a circulatory system to distribute it to all its cells, so the usefulness of the resources acquired from nature and used to produce commodities depends on an economic system that distributes the commodities to all its members. In nomadic bands, energy circulation can be simply sharing the food acquired, as in the gastrovascular cavity of the hydra, but with larger populations, it needs a market or class structure like feudalism to serve the role of heart and blood vessels.

Military institutions. War requires a special kind of social level behavior toward other spiritual animal, and thus, military institutions evolve in spiritual animals to generate such behavior. Since multicellular animals do not normally kill other members of their species to acquire free energy for themselves, they have neither behavior nor organs that are comparable to an army.

What comes closest to war in multicellular animals is animal behavior directed at protecting themselves from predators and competing species, such as threatening or aggressive behavior. That function must also be served in spiritual animals, though controlling that condition was, as we have seen, the original function of the mutually protective “altruism” of hominids. They roamed around in group carrying clubs to beat off predators.

There cannot be any exact parallel between multicellular and spiritual animals because of the essential differences between them. But as these comparisons suggest, this ontological explanation of the essential nature of spiritual animal leads us to expect spiritual animals to have more or less the kinds of social institutions that are found in actual human societies. There are probably further ontological necessary truths about them, and something more will be said about their evolution in discussing the philosophical spiritual stage (stage 10). But in order to derive all the kinds of institutions that inevitably evolve, we would have to trace the rational spiritual sate of evolution in more detail than I am here.

Religion as social science theory. A final comparison between multicellular and spiritual animals will bring out the essential nature of the object of social science, and suggest the limitations of social science at the rational spiritual stage. Though it does not appear so at this stage of history, the object of social science is the spiritual animal. Though it is merely a composite (or “dividual”) organism, it qualifies as a form of life, because it has the unity of any reproducing organism. The way that language coordinates the members behavior in social level behavior means that a spiritual structure, with both a social and a cultural aspect, goes through reproductive cycles as a whole.

The original and essential social aspect of spiritual animals is how their members are in continual linguistic interaction with one another. That works together with the cultural aspect, as we have seen, to guide its behavior as a whole. But with the evolution of social institutions, some of its social level behavior is regular, and that gives the social aspect a kind of structure. The institutions must all fit together, because they are ways in which a single spiritual animal acts as a whole over time. Indeed, they fit together like the organs that make up multicellular animals, except that they do not necessarily involve unchanging geometrical structures in space. They are patterns about the motion and interaction of the members, and so they give the spiritual animal an unchanging geometrical structure in space and time.

I will call it “social structure” because it is a structure of the social aspect of the spiritual animal as a whole. But it is important to keep in mind that social structure is not the kind of unchanging geometrical structure that could be a structural cause of social level behavior, because institutions are themselves just various kinds of social level behavior that are generated by its spiritual structural cause.

This limitation is overcome, as we shall see, when the institution of property arises, because that enables social level behavior to impose the kind of unchanging geometrical structure on the spiritual animal that can serve as a structural cause. Property ties individuals to particular pieces of land, and that is, as we shall see, the foundation for class structure. (See Philosophical stage: Possibility: Stages of social evolution.)

In the meantime, social structure does have an effect on the members, because as we have seen, the spiritual animal acts as a whole on its own members by promulgating laws, educating them and punishing them.

Social institutions are the social level behavior generated by rule following, that is, by the mutual acceptance of arguments about social roles, including the principles by which those rules are justified and the function of the institution is understood by its members. Since there are various kinds of institutions, there are various kinds of arguments about social roles, and they are all accumulated as part of the culture. But just as the rules governing the social roles of any given institution are arguments that become integrated by general principles as culture evolves by rational selection, so “social theories” about all the various institutions in a spiritual animal become integrated by even more general principles. The highest level principles governing individual behavior are basically religious.

Religion is a way of explaining everything in the world that is based on reflective understanding. Religions take many forms, including animistic views of nature, ancestor worship, polytheism, and theism, but it always affirms the existence of special beings whose behavior can be explained by their reasons, like subjects. That makes explanation too easy to be very compelling rationally, because it is just a matter of postulating some subjective being who does what needs explaining.

Religion has an important function, however, because it is ultimately a way of representing the spiritual animal of which they are part and what is good for that whole. It is used to justify the arguments and principles accumulated as the cultural causes of institutions. But religion cannot stop by affirming the good of the whole, because that in turn needs an explanation. Thus, religions typically expand to become the “principle” supporting all the arguments of society, explaining the natural world as well as the social world, and serving to justify principles of individual behavior as well as institutions and social level behavior.

Therefore, just as social theories are not just descriptions of institutions, but also practical arguments that generate the institutions that they describe, so the religion that integrates them all into a grand theory at the rational spiritual stage is not just a description of the spiritual animal as whole, but a practical argument that, in effect, generates all the behavior of the spiritual animal as a living organism over time.

The cultural aspect is, as we have seen, a structure of the spiritual animal as a whole, It is complete, at least, in principle, in the brain of every member. But in order to function as the “plan” for social level behavior, the correspondence it entails between the worldview of each individual and the social world itself involves the same part-whole relation required in primitive spiritual animals (and in the mechanism of embryological development). Not only does each part contain the entire plan for the higher level organism, but it also identifies with a certain part of that plan.

That means that the correspondence between images in the brain and the spiritual animal as a whole that is required to generate the social world in the rational spiritual animal is one in which each rational subject sees the social world (and the natural world) from the vantage of a particular member of the spiritual animal occupying certain social roles. Thus, religion not only integrates all the arguments about the social (and natural) world, but also justifies the behavior that the social world requires of each member to that member. The unity of the spiritual animal as a whole is not only mirrored in the culture generally, but mirrored in a slightly different way in the brain of each member.

Individual and spiritual self interest. The difference between natural science and social science (including both the science of individual subjects and the science of their social world) is a dichotomy in rational culture that occurs within theoretical reason. But there a also dichotomy between theoretical and practical reason, and within the arguments of practical reason, there is another dichotomy. It arises, because reason must guide the behavior of both the spiritual animal as a whole and its individual members. This dichotomy mirrors the difference between the two parts of social science described above (the science of subjects and the science of the social world), but it is not reducible to them, because it is concerned with what is good for them, not merely explaining their behavior.

The good is what contributes to natural perfection, which is the direction of evolutionary change, and thus, at each stage of evolution, there is a new way in which things can be good or bad. But at the rational spiritual stage, there are three different ways in which things can be good or bad, because there are three different forms of natural perfection to which things can contribute. I will call these ways in which things can be good or bad “interests,” because they can all be goals of behavior guided by reason.

Rational interest. We have already seen that reason itself has an interest, because the evolution of arguments by rational selection is change in the direction of the natural perfection of culture. Culture is naturally perfect when its arguments discover the true, the good and the beautiful (or come as close as possible for arguments at its stage). That is how reason contributes to the power of rational beings. Thus, things are good or bad for culture or reason. For example, what contributes to cultural evolution, such as institutions or individual behavior that foster the exchange of arguments and promotes their rational selection, is good because it contributes to the natural perfection of culture. What is good in this way is in the interest of reason itself.

Spiritual interest. Culture evolves, however, within rational spiritual animals, and spiritual animals themselves evolve by reproductive causation in the direction of natural perfection for organisms of their kind. As we have seen, spiritual animals impose natural selection on themselves by their own reproduction in the harsh form of warfare, and as a result, they gradually change in the direction of natural perfection for them. Cultural evolution is a trait that evolves within them because it enhances their power as rational beings to control the conditions that affect their reproduction at the social level. Since there is a natural perfection for rational spiritual animals, things can be good or bad depending on whether they contribute to it or they detract from it. Thus, spiritual animals have an interest, which I will call the spiritual interest.

Individual interest. There is, however, a distinct natural perfection about the individual members of spiritual animals, because the evolution of spiritual animals by reproductive causation involves the simultaneous evolution of its members by reproductive causation. This has no precedent, as we have seen, in the history of biological evolution. Though evolution on two levels at once played a role in the evolution of prokaryotic life and eukaryotic life, it stopped with the evolution of the biological behavior guidance system that made them a form of life (though eukaryotes compensated for this by the evolution of sexual reproduction). Multicellular animals are not parts of spiritual animals in the same way as cells in multicellular animals, because the members of spiritual animals continue to impose natural selection on themselves by their own sexual reproduction within spiritual animals, even as their spiritual animal evolves in a parallel way on the social level. Whereas in spiritual animals, reproductive causation is at work on both levels, in multicellular animals, reproductive causation is at work on only one level of biological organization, the multicellular level. (Multicellular animals reproduce by constructing an entire new multicellular animal from a single fertilized egg cell, and since individual cells reproduce only as part of that process of embryological development, they do not impose natural selection on themselves at the cellular level — though as eukaryotes, sexual reproduction serves a similar function.) The simultaneous evolution of organisms by reproductive causation on two levels of biological organization implies that evolutionary change is in the direction natural perfection at two levels of biological organization at once.

Since reflective subjects impose natural selection on themselves within spiritual animals by their own reproduction, they evolve in the direction of natural perfection for the multicellular animals who are parts of spiritual animals. It is as if membership in spiritual animals were their ecological niche and they were adapting to it. But since that means individuals change is in the direction of a kind of natural perfection, there is a way in which things are good or bad for the individuals. What contributes to the natural perfection of rational subjects is good for them, and the bad is what detracts for their natural perfection. Thus, individuals have an interest as individuals, and that is what I mean by individual interest.

A difference between the interest of the individual and the interest of the spiritual animal is entailed, therefore, by our ontological derivation of reproductive global regularities, because spiritual animals are an inevitable stage of evolution. In addition to pursuing the interests of reason itself, reflective subjects use reason to pursue both the interest of their spiritual animal and their individual interest. This is evident on reflection from the point of view of the subject, but the nature of reason at the rational spiritual stage does not provide any adequate way of explaining the relationship between the individual and spiritual interest. Though cultures normally assume that spiritual interest has priority over individual interest, the only explanations that can be given of it at the rational spiritual stage are religious, thereby sewing their worldview together by appeal to magic and mystery.

In order to see what is good and bad for reflective subjects, let us consider what ontological philosophy implies about how the reflective subject is related to each of these interests that evolve at the rational spiritual stage. That is, in what sense are they aspects of self interest?

Rational self interest. Reflective subjects have an interest in reason insofar as they are producers of culture, participating in the process of discovering the true, the good and the beautiful. Those goals are inherent in reason itself, because the natural perfection of culture is the direction of the evolution of arguments by rational selection. And what is exchanged in the process of pursuing those goals includes not only theoretical and practical arguments, but also what Aristotle would call arguments of “productive reason” (a kind of practical reason having to do with the goodness of products rather than the goodness of the actions themselves).

Though reflective subjects have a rational interest because they participate in cultural evolution, that is merely an interest in knowing, and it does not guide their behavior except as participants in cultural evolution. What is in the interest of reason is good for them only insofar as they are the producers of cultural evolution, that is, as individuals considering alternative arguments and rationally selecting the most coherent argument. That is a merely cognitive interest.

However, reflective subjects can also have an interest in reason that affects their behavior in other ways, because they are also consumers of culture. Reflective subjects draw on the arguments accumulated as culture to judge what is good in the particular situations they face and, thus, attain their goals through rational action.

The capacity to use reason to guide behavior is not, however, merely a means to goals that individual’s already have. It changes their nature, as we shall see. It gives reflective subjects new goals in addition to those that come from being participants in cultural evolution, because it increases their power to pursue goals generally. Thus, the maximum holistic power of rational subjects is greater than that of subjects who use reason merely to pursue the goals of their animal behavior. The power of reason transforms the reflective subject into a rational being, that is, a reflective subject whose behavior is guided by reason not merely in the selection of means, but also in the selection of goals. And individuals can pursue goals beyond what controls the conditions that affect their reproduction. Thus, what is good or bad for the individual depends on what contributes to their natural perfection as rational beings, and that includes both an individual interest and a spiritual interest (and, in both cases, both necessary and optional goals). That is, as we shall see, their self interest as rational beings.

What transforms reflective subjects into rational beings is submitting to reason. Reflection enables the linguistic animal to represent the causes of his own behavior as causes of his behavior in the process of guiding behavior. But as I suggested earlier, reason is not merely the capacity to monitor the causes of one’s behavior during the behavior guiding process, because reflection on the causes of behavior eventually changes how behavior is caused. Rational imagination enables subjects to see the actual causes of behavior against the background of what is possible, and reasoning about what to do discovers new and better goals of behavior. Assuming that the subject can do what reason discovers to be good, this is a new way of causing behavior. Reasons are causes of behavior that are represented as causes of behavior as an essential part of the process by which they cause the kind of behavior they do, and this change in the causes of behavior can change the kind of behavior caused.

Reason becomes a behavior guidance system by taking over the control of behavior from animal desires. Since animals act on their strongest desire at the moment, what enables reason to take control is a desire to be rational. It is no mystery where this desire comes from, for we have been tracing its evolution from its origin in the dominance hierarchy established among social animals by their biological behavior guidance system.

In social animals, as we have seen, conflicts are resolved by a dominance hierarchy in which a confrontation of some kind among members determines a ranking, or “pecking order.” Desires provided by the biological behavior guidance system motivate losers in that confrontation to submit to more dominant members, even though it may mean not acting on other strong animal desires, such as the desire to eat or to mate.

This desire to submit became the source of the leader’s power to generate social level behavior in primitive spiritual animals, but since the leader coordinates their behavior by using language to assign members special tasks in his plan, it becomes the desire to conform one’s behavior to a linguistic representation of it. The linguistic system of representation is located in the left hemisphere, and the dominance of the left hemisphere made it possible for linguistic representations of behavior to determine motor output to the body. But which linguistic representations would control behavior was determined by the leader, because the members were motivated to do what the leader told them to do, even when they had strong animal desires to the contrary, such as fear, fatigue, lust and anger. The desires to submit to the leader was inevitably connected to linguistic representations, because those spiritual animals in which the use of language was not a reliable was of generating social level behavior would be vanquished by spiritual animals in which it was.

With the evolution of psychological sentences at the rational spiritual stage, naturalistic imagination evolved into rational imagination, and the linguistic interaction that guided behavior was no longer merely the distribution of a plan by the leader, but rather arguing about what they should do in the situation. The exchange of arguments enabled them to see which intention made their world views most coherent, and thus, it led them to agree about which alternative to choose. Thus, the desire to submit to the instructions of a leader evolved into the desire to submit to reason. This transformation in the nature of reflective subjects was assumed in the foregoing explanation of institutions as regular social level behavior generated by the mutual acceptance of arguments about how to behave in various situations.

The two stages by which rational spiritual animals evolve from nomadic bands of hominids is a case of ontogeny recapitulating phylogeny, for there is a similar two-step process by which individual subjects come to submit to the authority of reason.

Individuals enter spiritual animals as babies, mere bodies that must be handled by other members until locomotor and manipulative schema can develop into a spatial imagination. They can see themselves as bodies in a world of objects in space with the capacity to manipulate other objects, and they have a desire to submit to their parents in ways that do not depend on the use of language.

As their sensory-motor skills are developing, their brains are also internalizing a natural language, and that makes it possible for them to submit to the parent’s linguistic instructions. At first, the child can use only natural sentences, but some time between the ages of 3 and 5 they acquire the use of psychological sentences, thereby learning to distinguish how the world appears to a subject from what it really is. But even after the child acquires a faculty of rational imagination and the capacity to reflect on her own psychological states, her status in the family is like that of a member of a primitive spiritual animal, because the desire to submit to a leader is a desire that is normally attached to her parents or guardian. Parents are responsible for devising the plan, and the child looks to the parent for guidance. Children are not quite like members of primitive spiritual animals, for they are also acquiring additional brain structures by which they can use rational imagination to understand the arguments and judge arguments by their coherence.

Adolescence recapitulates the change in the desire to submit to a leader that occurred when reason evolved. Just as the authority of the leader passed to the arguments they mutually acknowledged, so the authority of the parent passes during adolescence to the arguments acquired from the culture. Thus, the child becomes a rational being. It is a transformation that in which the child matures physiologically and acquires an interest in sex, and not surprisingly, it is marked by a rebellion against the authority of parents, a concern with her peer group, and a sudden interest in her own identity.

Autonomy of reason. As the desire to submit to reason develops, the child become autonomous or has free will, because its behavior comes under the control of reason. Reason discovers the good by a process of arguing about what to do, and the desire to submit to reason enables the subject to do what is good because it is good, that is, simply because she believes that it is good. Thus, reason takes control of behavior. “Will” is the traditional name for the intentions formed by practical reason.

This change in the animal behavior guidance system is aptly called “free will” or “autonomy,” because it enables the subject to act contrary to strong animal desires. When the subject has reason to believe that some course of action is good, she can act accordingly even when she has strong immediate desires to do what she considers bad, because the desire to submit to reason is normally the strongest desire. Thus, the rational subject has self control and can be responsible for doing what is good.

It may not seem that what puts reason in the driver’s seat is a desire, because it is normally felt only when it is not satisfied, much like the desire to breathe. When a subject fails to do what she has chosen to do because she believes it is what is good, she typically feels shame (or guilt as well, if it is a failure to do what is morally good). That is what it feels like to fail to satisfy the desire to submit to reason, and reflecting on the cause of that feeling tends to strengthen the desire to be rational. The fact that one has only a feeling of power and well being when it is being satisfied does not mean that it is not a desire at all. In animals whose behavior is guided by desire, such a modification of the affective system is the most efficient way of bringing behavior under the control of reason. But the desire to be rational is not just another desire, for it is the foundation of reason as the behavior guidance system of the subject.

One is not always able to do what she believes to be good, for example, when she is tempted to eat too much by the availability of delicious food. Incontinence, or weakness of will, as it is called, can be caused by a weakness in the desire to submit to reason, for example, when one is tired, depressed or demoralized. One is responsible for such incontinent behavior, because the desire to submit to reason is normally strong enough to resist animal desires, at least, it is when one understands the means that are necessary to attain the goal one is pursuing.

Individual self interest. There are basically two ways that the autonomy makes the rational subject more powerful as an individual than other multicellular animals. One is the ability to act in the interest of his individual Self, or what is traditionally called “self interest.” The other is the capacity to pursue goals beyond those that control conditions affecting her own reproduction., or necessary goals and optional goals, respectively.

Necessary goals of individual self interest. The reflective subject has a Self, as we have seen, because her faculty of rational imagination (specifically reflective understanding) enables her to tell a story about her self by which she recognizes her identity over time. This is the result of accepting the arguments of the science of subjects that have accumulated as culture. But with the desire to submit to reason, it gives the subject far more power to attain her goals.

By recognizing that the subject will have desires in the future that are not currently strong, reason puts her in a position to devise a plan for what to choose in a whole series of situations that enables her to satisfy them more completely than simply acting on the strongest desire at each moment. The ability to act at each moment in a way that will maximize the satisfaction of her desire over her whole life makes her far more powerful than other animals, because non-rational animals are locked in the immediate present and have only their affective system to choose which goal to pursue in each situation. In selecting how to behave in any situation, animals must rely on the priorities among goals set by the biological behavior guidance system as a result of biological evolution. Though that maximizes the holistic power for animals of their kind, there is a way to increase the power to control relevant conditions. With the faculty of reason and a desire to submit to its conclusions about how to behave, she can act with foresight and pursue long term goals, or goals that can be attained only by how actions work together over a long period of time.

This power is often what is meant by “self interest,” and that is appropriate, because it is the capacity to act in the present moment for the interest of one’s Self. The Self includes the whole reproductive cycle, and thus, by taking responsibility for doing what is in its interest, the rational subject is constructing a spatio-temporal structure, or a four dimensional object.

If we think of the natural perfection of the individual life as the beauty of the Self, the rational subject may be likened to an artist painting a portrait of herself. Her paints are behavior directed by desire at certain goals, and her canvas is space and time, including all the particular situations she encounters and what others contribute. She paints her portrait in a world of objects in space, except that it is also laid out in time. Her painting is skewed in the direction of the future, since, at any point in the process, the past is done and cannot be undone. And the future can be seen only incompletely and vaguely through the telescope of causal connections believed to hold in the world, since some features are painted in by unexpected events in the natural and social world. It is as if the canvas of space and time required one to complete the painting from left to right. The rational subject is unable to go back and change the paints already applied on the left, but must always apply paints on the right side of what has already been painted, and do it so that, when one has worked one’s way to the right edge of the canvas, everything will fit together as the portrait of one’s Self. The main tool in constructing such a work of art is a life plan. That is, the way to make the brush strokes one applies add up to the portrait of a beautiful Self in the end is to use one’s understanding of the world and how it works to figure out how to behave now in order to fulfill as many of the goals set by desires is as harmonious a ways as a single body can in a world of objects in space over time.

This is the effect of having a Self as seen from our ontological perspective, but it may not be how self interest is ordinarily understood. The temporal structure of the Self is obvious enough in the subject’s recognition of the inevitability of death, but the condition of actually existing only at the present gives one a different perspective. Indeed, one has already lived part of that temporal whole by the time one becomes fully reflective, and although the story one can tell about oneself extends back even beyond what can be remembered to the stories that parents tell about the earliest years, the future is largely open, like a clean canvas. It is not easy to predict all the situations one will face in the distant future, and that makes it difficult to develop a plan that will cover a whole life, even though that is what self interest involves at its most coherent. Thus, the way to take responsibility for that future seems to be to follow certain principles of prudence and to think of one’s interest as having a certain kind of Self, where the Self is something that one has and carries along. That makes it seem that the pursuit of self interest, or the good life, is a matter of observing certain principles and priorities in situations as they arise and filling in the details as the time comes to act on them.xcv Instead of acting for the sake of one’s life as a whole, one tries to live up to a self-image, that is, have an identity of a certain kind. Thus, it is not always clear that serving one’s self interest is the job of constructing a Self as a whole life. But toward the end, it becomes clearer that the Self one has is the life that one has led, and then one sees the portrait one has painted and knows who one really is.

Optional goals of individual self interest. The capacity to act in the interest of her Self in the sense of maximizing the satisfaction of desires over a whole lifetime is, however, only one aspect of the autonomy that comes from being a rational subject. We have been assuming that the goals of individual behavior are determined by desires, because if we set aside the goals that are justified by religion, that is how it appears from the point of view of the reflective subject. But from our ontological vantage, we have a deeper explanation of what makes the goals of animal behavior good, and taking it into consideration, we can see another way in which rational subjects are more powerful than other animals.

Desires set goals for subjective animals that guide their behavior to control the conditions that affect their reproduction, and as they approach natural perfection for animals of their kind, the relative strengths of their desires in the various situations determines a priority among them that makes them as powerful as possible for them over their whole reproductive cycle. What makes the goals good is that they control relevant conditions, because that is how their animal behavior contributes to their natural perfection.

Rational subjects are more powerful than other animals, because, as we have seen, instead of relying on the priorities among goals set by the strength of desires, they can choose goals in the present situation that will work together with behavior in other situations to satisfy the entire range of their desires over a period of time more reliably and completely. But that is to assume that the desires of rational subjects also direct them to goals that control conditions that affect their individual reproduction, and that is not necessarily true. One reason it is not true is that rational subjects are parts of spiritual animals, and they have desires that adapt them to that ecological niche and control conditions that affect the reproduction of the spiritual animal as a whole. But our concern here is another reason it is not true. Reason itself gives the subject the capacity to make goals part of their individual self interest, that is, good for them, even though they do not contribute their reproduction on either level of biological organization.

Arguments evolve within spiritual animals by rational selection, that is, when they result in a more coherent worldview. This is basically an aesthetic judgment, for it depends on rational imagination and the capacity to compare the beliefs or intentions proposed by arguments against the background of established beliefs and intentions. It seeks an optimum that can be recognized only by comparison with other possibilities, and thus, it is ultimately a judgment about how to do the most with the least, the basic criterion of natural perfection. Rational imagination includes, however, an understanding of causes in both the natural and the social world, and thus, it is possible to recognize the natural perfection of other organisms, ecologies, cultures, or spiritual animals that have evolved by reproductive causation. Thus, it is also possible to see what is good for them, because they can see what contributes to their natural perfection. In short, rational beings can discover things that are good even when they do not contribute to their own natural perfection.

The autonomy that comes from reason enables the reflective subject to do what is good because it is good, that is, simply because she believes that it is good, whether or not she already desires it. Thus, when rational subjects recognize that something they can control would be good by seeing how it would contribute to natural perfection in some way, they can choose to pursue it as a goal. To choose it as a goal of one’s own behavior is to make it good for one self, that is, as part of one’s individual self interest. Thus, the individual can pursue goals that are good for them, even though they do not control conditions that affect their own individual reproduction.

This explanation of the nature of reason entails internalism. “Internalism” is the view that the motive for pursing the good does not require a desire for the goal, but rather comes from simply recognizing that the goal is good. When reason is in the driver’s seat, that is how behavior is caused. It is the belief that the goal is good that motivates the subject to pursue it. Though he would not have this motive without having a desire to submit to reason, that does not make this an externalist theory about value judgments, for the desire to submit to reason does not come from a desire for the goal being pursued. On the contrary, a desire for the goal comes from the desire to submit to reason. The desire to submit to reason is neutral among goals, for it gives the subject a motive to pursue whatever goal reason judges to be good, regardless what she may feel about the goal otherwise.

This does not mean that a rational subject can make any goal good for himself by choosing it as a goal. The goal must already be good in some way for something, or else it would not be rational to choose it. Choosing to pursue the goal merely makes it good for the rational subject, that is, a part of his individual self interest. However, what is good objectively must be understood to include not just what contributes to the natural perfection that comes to exist by reproductive causation, but also to artificial forms of natural perfection, such as craftsmanship and works of fine art.

As one commits oneself to the goal, one comes to have a desire to pursue it, but in this case, the desire may come only from the desire to submit to reason and its inherent interest in the beautiful. Thus, these goals are already included in one’s individual self interest as explained above, that is, as maximizing the satisfaction of desire. But from our ontological perspective, it is important to distinguish them from the goals that are good because they control conditions that affect one’s individual reproduction, including most of the goals set by animal desires.

Let us call the goals that are good for the rational subject because they control conditions affecting his own reproduction “necessary goals”, or goals of “narrow individual self interest,” and the goals that are good for him because he chooses to pursue them “optional goals,” or goals of “broad self interest.” What contributes to the natural perfection of a rational subject includes, therefore, both necessary and optional goals (both what is in his broad self interest as well as what is in his narrow self interest), though in cases of conflict, necessary goals take priority over optional goals.

Reason makes the individual more powerful than other animals, therefore, in two way—in the first instance, by making them better able to control conditions that affect their individual reproduction, but beyond that, by enabling them to pursue other goals that are good because of contributing to other forms of natural perfection or to artificial perfection, such as works of art (and to pursue those goals as efficiently as possible).

Spiritual self interest. The other half of the dichotomy about arguments of practical reason has to do with the interest of the spiritual animal, as opposed to the individual subjects who make it up. Things are good or bad for the spiritual animal in a way that parallels how things are good or bad for individuals, because with evolution by reproductive causation working on both levels of biological organization at once, organisms on both levels change gradually in the direction of natural perfection for organisms of their kind. And since both are rational beings, both have both necessary and optional goals.

The relationship between these two biological levels, as we have seen, has no precedent in biological evolution. Though spiritual animals are made up, like multicellular organisms, of simpler organisms, the parallel between these two part-whole relations is not complete.

In multicellular animals, natural selection works only at the higher biological level, because all the member cells of a multicellular organism derive from a single, fertilized egg cell. Though sexual reproduction makes it possible, as we have seen, to focus natural selection so that lower level structures are what evolves, traits are selected in cells only when they are good for the multicellular organism.

In the evolution of spiritual animals, however, natural selection works on two levels of biological organization at once. At the same time spiritual animals are imposing group-level natural selection on themselves by their reproduction (division into smaller groups), individual members are imposing natural selection on themselves by their sexual reproduction within spiritual animals, selecting some traits, perhaps, that are not good for the spiritual animal.

With reproductive causation shaping both the spiritual animal and its multicellular members to be powerful as possible over their reproductive cycles, individuals evolve toward a natural perfection of organisms that is subject to the constraint of being parts of spiritual animals, and spiritual animals evolve toward a natural perfection of organisms that is subject to the constraint of being made up of autonomous individuals.

Spiritual interest. There are, therefore, two kinds of interests. In addition to the interest of each individual (or what I am calling “individual self interest”), there is the interest of the spiritual animal as a whole. I will call it the “spiritual interest.”

Spiritual animals evolve toward natural perfection for organisms of their kind because their multicellular members (and their behavior) are bundled together as parts of a spiritual structure that goes through reproductive cycles as a whole and, thus, they impose natural selection on themselves at the group level by their reproduction. War makes group level selection very efficient, and as we have seen, reason evolves as a way of controlling relevant conditions having to do with choosing how to behave toward other spiritual animals. Since they have, or come to have, the optimal part-whole relation by which natural perfection is defined, things are good for spiritual animals because they contribute to that kind of natural perfection. There is, therefore, a spiritual interest, the interest of the spiritual animal.

Since human society is a spiritual animal, it has, like all animals, behavior as a whole directed at goals which control conditions affecting its reproduction. Plans for group behavior arise by rational selection from arguments being exchanged about what the group should do, though the choice of what to do is normally structured by a government, because spiritual animals act mainly through social institutions. The good pursued by spiritual animals includes, as we have seen, the usual animal goals. Some group-level behavior acts on nature to acquire usable energy from nature and to protect itself from danger, such as predators and natural disasters. But some behavior directed at other objects in space has no parallel with multicellular animals, such as crucial decisions about war and peace in relation to other spiritual animals. Other behavior acts on parts of its own body in order to provide for the reproduction of its members (kinship system), to educate them so that they can take advantage of the culture, and to protect its health by punishing wrongdoing.

These are necessary goals, because they are conditions that social level behavior must normally control in order for the spiritual animal to reproduce as a whole, if the occasion ever arises. They are how the non-reproductive work get done. But since spiritual animals are guided by reason, the autonomy of reason also makes it possible for them to pursue goals simply because they are good, even if they are not good for the spiritual animal. The can, for example, act in the interest of other spiritual animals, other animals, or the ecology. By choosing to pursue such goals, they become good for the spiritual animal. But there are optional goals, because they do not control conditions that affect their social level reproduction.

Spiritual interest as self interest. The interest of the spiritual animal is not, however, just an interest of the spiritual animal as a whole. It is an interest of each rational subject who is a member of it. That is what I mean by calling it “spiritual self interest.” Since the interest of the spiritual animal is as much an interest of the rational subject as his individual interest, he would have both a spiritual self interest and an individual self interest. The parity of these two interests for the rational subject follows from the nature of reason itself. Reason is a unique kind of behavior guidance system, because it is responsible for animal behavior on two levels of biological organization at once. And yet the ultimate agent for both functions is the individual.

The original function of reason was, as we have seen, to guide the spiritual animal’s behavior in making choices about war and peace; reason was naturally selected at the group level by success in war. But since reason works by individuals using psychological sentences to operate their own imaginations, they can simulate the reasoning of other subjective animals, and individuals inevitably came to use reason to see into one another’s minds, as well as to reflect on their own. Thus, reason took over the function of guiding behavior at the individual level, as well as the group level. Moreover, in order to serve its behavior guiding function on both levels, reason must not only discover what is good, but also do it.

In both cases, the power of reason to discover what is good is a result of cultural evolution, or the effect of a new, contained form of reproductive causation that necessarily involves both levels. Cultural evolution depends on the spiritual animal as a whole, because the exchange of arguments is how arguments reproduce, forcing a natural selection to be made. And it depends on the individual, since reproductive success for arguments is determined by rational selection, that is, by the individual’s judgment of what is most coherent.

When it comes to doing what it good, each individual subject can, on his own, use the arguments that have evolved to discover what is in his own self-interest (because the crucial power of reason is seated in the parts of the spiritual animal), and he can act in his self-interest independently of others (for he has control over his individual, physical body). But in order for reason to guide behavior in pursuit of the good of the spiritual animal, agreement among the members is required, in principle, for both the judgment about what is good and doing what is good, since only through their cooperation with one another is the spiritual animal able to act at all.

In other words, not only does the spiritual animal not have a body of its own, apart from the bodies of its members, neither does it have a mind of its own, apart from the minds of its members.

The rational subject is, therefore, the ultimate agent behind behavior on both levels of biological organization. He is responsible not only for pursing his own good as an individual, but also for pursuing the good of his spiritual animal. The rational subject thinks of himself as his Self, and thus, we can describe this twofold responsibility by saying that he has a spiritual self interest as well as an individual self interest. It comes from his nature as a rational subject, because membership in a spiritual animal is part of the essential nature of the rational subject. As such, he shares responsibility, in principle, for choosing which social-level goals the spiritual animal will pursue, and he has certain tasks to perform in acting on those decisions.

The balance between individual and spiritual self interests. Though the rational subject has both interests and must pursue goals on both levels of biological organization as part of the Self he constructs during his lifetime, individual and spiritual self interests are different ways in which things are good or bad, because they contribute to two different kinds of natural perfection. Thus, they may be in conflict with one another. And that raises the question of which takes priority, that is, which goal it is good for the rational subject to choose.

Even in multicellular organisms, the interest of part is not identical to that of the whole. Things can be good for the cell, because cells have the natural perfection of organisms. And what is good for the cell is good for the multicellular organism as a whole, because cells are the lower level organisms whose behavior is coordinated in constituting the multicellular organism. Thus, what contributes to the natural perfection of the cell necessarily contributes, by way of the cell, to the natural perfection of the multicellular organism. But the relationship is not reciprocal. What is good for the whole is not necessarily good for the part. Normally, what is good for the multicellular organism is good for its cells, since the whole provides the environment in which the cells can exist and their traits can control conditions affecting their own reproduction. But the good of the whole takes priority over the good of the cell. There are situations in which multicellular animals sacrifice their own parts, for example, in sloughing off skin cells and cells dying in the process of embryological development. Thus, the part has an interest that can conflict with the interest of the whole even in multicellular animals.

The interests of part and whole diverge even further, however, in spiritual animals, and that may make it seem impossible to reconcile these two interests of the rational subject. In the spiritual animal, as in multicellular organisms, what is good for the whole is not necessarily good for the part. Though the spiritual animal does provide energy and protection for the individual, its interest is not always good for the individual. The spiritual animal may also sacrifice its parts for social-level goals, for example, requiring members to fight in wars where many will die and more will be injured. Or in natural disasters, it may have to sacrifice some for the spiritual animal itself to survive. But in spiritual animals, not only is the interest of the whole sometimes not good for the part, the interest of the part is also sometimes not good for the whole. That is possible in spiritual animals, even though it is not possible in multicellular organisms, because reproductive causation is at work on both individual and social levels at the same time. Traits of individuals are naturally selected by the individual’s success in sexual reproduction, and what controls conditions affecting individual reproduction may not control any condition affecting the whole’s reproduction. Though rational subjects evolve toward the natural perfection for organisms of their kind subject to the condition of being members of spiritual animals, what is in the individual’s self interest may conflict with the interest of the spiritual animal.

For example, it may be in one’s individual self interest to commit treason to receive a bribe, but it is clearly not in his spiritual self interest. More generally, the pursuit of individual self interest can impair the capacity of the spiritual animal to pursue its social level goals by leading to conflicts among its members that make them unable to cooperate.

Morality. That is why morality evolves in spiritual animals. The spiritual animal needs cooperative relations among its members to pursue its own goals, and thus, its natural perfection requires that limits be placed on the pursuit of individual self interest. The function of morality is to limit the pursuit of individual self interest so that the spiritual animal is able to pursue its goals, that is, for the sake of spiritual self interest.

The arguments that evolve in spiritual animals about what individuals should do in relation to one another and in relation to the institutions and laws promulgated by the government restrict that what they can do in pursuit of goals of individual self interest. More will be said about the content of these rules in discussing necessary truths about what ought to be, but for now, let mention a few basic aspects of these rules.

Some moral rules have the function of avoiding conflicts among members that would make them unable to cooperate. The pursuit of goals of individual self interest could lead rational subjects to act in ways that harm other members, such as lying about them, deceiving them, stealing from them, and even killing them. Such harm to other members would quickly escalate into warfare, because rational subjects are quite able to harm others in return, since they have desires that have evolved to enable them to fight wars. Thus, in arguing about what individuals should do, the members of spiritual animals will come to mutually recognize certain limits on the pursuit of self interest.

These moral limits will tend to treat members equally, because they are parts of the evolution of culture by rational selection. Moral rules must be acceptable to everyone, because those that favor some members over others will not be rationally selected by the latter. Equality of treatment mirrors the symmetry among rational subjects in the spiritual animal. (There may be institutions and social structures in which moral rules do not treat members equally, but since the functions responsible for them are not recognized, the inequalities may be justified inadequately by appeal to religion.)

Furthermore, these moral limits will tend to leave members with the maximum freedom to pursue goals of individual self interest compatible with the same freedom for others, because as culture evolves, individual will not accept arguments that limit their behavior more than necessary. (But limits on the maximum possible freedom may be imposed by the religion of the spiritual animal in order to ensure the general acceptance of the culture by public expressions of submission.)

There are also moral rules requiring members to play their roles in generating social level behavior, that is, requiring them to obey the laws promulgated by the government and to participate fairly in its institutions. But since the rules governing duties to the spiritual animal are products of cultural evolution, they will also tend to treat members equally and impose the minimum burdens on them.

Justice. Morality is only part of the balance between the individual and spiritual interests, the part that affects the behavior of members generally. But the spiritual animal can also act as a whole on its own members, and since the rules governing the behavior of the spiritual animal as a whole are also products of cultural evolution, there are comparable limits on its pursuit of goals of spiritual interest.

The spiritual animal acts on nature as a whole through economic institutions, but since each member needs part of the product of that activity to control the conditions that affect his own reproduction as an individual, the arguments that evolve by rational selection will tend to require that every member that puts forth a reasonable effort to cooperate in generating social level behavior receive a sufficient portion to pursue the goals of his narrow individual self interest. That is the requirement that the spiritual animal provide for distributive justice: the spiritual animal must make it possible for each member, with a reasonable effort, to be able to attain the necessary goals of individual self interest.

Punishment is the most directly harmful way that the spiritual animal acts on its members, but rules providing for the punishment of wrongdoers will inevitably evolve, because it protects members against the harm caused by violations of moral limits. But since the members are potential objects of such behavior, judicial institutions will tend to follow procedures that ensure that only the guilty are punished. That is the requirement that the spiritual animal provide for retributive justice.

The generation of social level behavior can also harm individuals, for example, by requiring them to risk their lives in war or in responding to natural disasters. Rules permitting such harm to individuals will be accepted as culture evolves, because those conditions must be controlled or the spiritual animal will not survive and be in a position to reproduce. Since such harm is the necessary means to the attainment of necessary goals of spiritual interest, they are in one’s spiritual self interest, and even though it may mean that the individual dies, it does not conflict with the attainment of necessary goals of individual self interest, because that risk is inherent in the ecological niche in which the individual pursues goals that control conditions affecting individual reproduction.

But rules will not evolve that allow the government to inflict such harm on individuals for optional goals of spiritual interest, for example, because of the greater good the harm does for other individuals, because such arguments will not be accepted by those who recognize that their individual self interest might be sacrificed for the good of others. That is the requirement that the spiritual animal recognize inviolable rights of individuals.

Thus, just as rules of morality that rational subjects must observe limit the pursuit of their individual self interest because of their spiritual self interest, so rules of justice that the spiritual animal must observe limit the pursuit of spiritual self interest because of the individual self interest.

Content of rules of morality and justice. There is a necessary content to the rules of morality and justice, because they are basic to the part-whole relation whose optimum is the natural perfection of the spiritual animal. Mutual acknowledgment of rules of morality and justice is as necessary to way in which individual behavior is coordinated in social level action as the right messenger molecules are to the relationship by which cells are bundled together in multicellular animals. That is, just as the physical body’s behavior depends on its cells having normal relationships, so the use of language to generate social level behavior in a spiritual animal depends on its members having normal relationships in which they mutually acknowledge rules that require cooperation, limit the pursuit of self-interest to protect other individuals, and respect the rights of individual members.

The publicly recognized symmetry among members does not mean that social rules permit no differences in benefits and burdens. It means only that differences in treatment must be justified by differences among the members. It would be obvious that there are relevant differences between males and females, between adults and children, and between young and old, and so the kinship systems would tend to reflect these differences in assigning rights and duties. Likewise, political institution give the leader and other officials powers that others lack. Such differences are how institutions coordinate social level behavior. But since they are generated ultimately by the exchange of arguments, they are reformed when abuses are recognized, and institutions continue to be modified until they prescribe differences in treatment only when they are justified in terms of recognized functions of the institutions.

Still, such rules of morality and justice are tendencies of cultural evolution. Culture evolves by a rational selection that depends on all the members of the spiritual animal, and rational subjects prefer arguments that maximize the coherence of their world views. As noted above, there are countervailing factors that may divert moral rules from this natural perfection of culture, and there may be spiritual animals in which cultural evolution itself is so inhibited that it fails to discover the good. But discovery of these rules of morality and justice is the tendencies of cultural evolution, because they make the arguments of maximally powerful as a whole, and that is the natural perfection of spiritual animals at the rational stage.

Why be moral? Even before culture and the spiritual animal are naturally perfect, however, morality must take priority over the pursuit of individual self interest, for if it didn’t, spiritual animals could not pursue their good, the good of the group as whole. And there would be no rational subjects.

There is, however, a problem about why the individual should be moral, because he can often serve his individual self interest better by violating the limits of morality, and since his individual violation will not destroy the spiritual animal and may not even deprive him of the benefits of being a normal member (if he is not caught), he can individually enjoy the benefits of wrong doing. Why is it not rational to be immoral under such conditions?

From the point of view of individual self interest, the spiritual animal is only a means to attaining individual goals. It is like having a spiritual body, in addition to his physical body, because he can enlist the cooperation of other in goals that are good for him individually. And if he can avoid punishment, the wrong doing will not impair the spiritual animal’s ability to act sufficiently to affect the individual.

It may not seem adequate to answer that morality is in the spiritual self interest of the rational being, because this is a case where his individual self interest and his spiritual self interest conflict. To insist on being moral would seem to be simply to prefer spiritual self interest over individual self interest. But these two interests should be equal, because both are interests of the rational subject in the same way. As a rational subject, he is just as responsible for guiding behavior toward goals that are good on both levels. And in the case of conflict, he should be just as justified in preferring individual self interest over spiritual self interest.

The answer given by this ontological explanation of the nature of morality is that rational subjects do not face a serious choice between their individual self interest and their spiritual self interest. There is no ultimate conflict between these interests, at least, not in spiritual animals with distributive justice.

There are, as we have seen, two kinds of goals of narrow self interest, necessary and optional, and there are two kinds of goals of spiritual self interest, necessary and optional. Necessary goals of individual self interest includes all the goals that must be attained in order to control conditions that affect individual reproduction. These include not only the physical needs to lead a normal, healthy life, but also sufficient resources for normal social relations. (But it does not include reproducing itself, since that is not a condition that affects reproduction.) Optional goals of individual self interest includes all the goals that are good for the rational subject because he chooses to pursue them. This is possible, as we have seen, because reason enables the subject to recognize how things are good in virtue of contributing to natural perfection of various kinds, not merely his own, and it enables rational subjects to do what they believe is good.

Likewise for the goals pursued by the spiritual animal. But the observance of moral rules among its members is a necessary goal of spiritual animals, not an optional goal, because that is a condition that must be controlled in order to act as a whole.

In a spiritual animal with minimal distributive justice, moreover, morality does not conflict with the pursuit of necessary goals of individual self interest, because with a reasonable effort, any member may attain those goals. All that morality limits, therefore, is the pursuit of optional goals of individual self interest, that is, optional goals, which are good for the subject only because he chooses to pursue them. Thus, the choice would be clear to rational subjects who understood the real nature of the choice. Though spiritual and individual interests are equal, it is a choice between a necessary goal of one’s spiritual self interest and an optional goal of one’s individual self interest, and thus, the choice is clear.

Likewise, rational subjects acting as agents of the spiritual animal cannot justify sacrificing the lives of members unless it is a necessary means in pursuit of a necessary goal, such as winning at war, because it would be to prefer an optional goal of spiritual self interest over a necessary goal of individual self interest.

This is not, of course, how reflective subjects see morality at the rational spiritual stage. If their goals of individual self interest have a non-religious explanation at all, they are explained as satisfying desires, and thus, the fundamental difference between necessary and optional goals of individual self interest is not recognized. And since they do not see their society as a spiritual animal, they do not understand how they have a spiritual interest.

However, arguments do accumulate at the rational spiritual stage that convince rational subjects to be moral. Nor is it hard to see why arguments for being moral evolve in every culture, since that is the only conclusion that draws individuals into cooperation and enables the spiritual animal to act on the social level. But without an understanding of the nature of goodness or the nature of the spiritual animal, the reasons for being moral are seen through a glass darkly. It is, as we have seen, the function of religion, to provide the ultimate justification for the practical arguments accumulated as culture. Religion is a way of thinking about the good of spiritual animal and their own spiritual nature. This is what Durkheim argued a century ago. He saw God (or the sacred, as opposed to the profane) as a symbol for the group itself, and since religion represents the group as superior to the individual, he sees it as giving rational beings a motive for being moral. By acknowledging and publicly celebrating the good of the whole as something higher than individual self interest, religious institutions point to their spiritual nature, and that answers doubts about why they should be moral and generates institutions that enjoin them to be moral.

When the standard of rational coherence by which arguments are judged is no more demanding than at the rational spiritual stage, morality can be justified by confused and misleading talk about gods, supernatural powers, or nonphysical beings. Since reflective subjects have evolved as parts of spiritual animals, the desires to submit to reason is a presumption in favor of the arguments accumulated as their culture, and that attitude is simply reinforced by religious institutions. Priests of some kind have the roles of speaking for their spiritual nature, and since it is not enough simply to say that the good of the whole is good for the individual, they invoke the authority of ancestors, threaten punishment by spirits, or warn of the consequences for immortal souls in an afterlife. This is the justification of the principles on which all their practical arguments are based.

When religion fails to convince members of its practical arguments, their conformity can usually be ensured by an evolutionary elaboration on the basic mechanism by which individuals submit to reason in the first place. Punishment is functional in two ways. First, as already suggested, it helps keep civil war from breaking out. Victims of violations of moral rules are roused to anger and inclined to respond to wrongdoers with war-like behavior, but these desires can be satisfied peacefully by the spiritual animal as a whole stepping in to restore the moral balance. Second, punishment is not just revenge. Nor is it just a penalty, as if it were a price that must be paid for misbehavior. Punishment tends to restore the moral balance in another way, because it is a formalized reenactment of the violent confrontation by which a dominance hierarchy is established even among non-linguistic social animals. Punishment tends to restore the motivation in the individual to be submit to the arguments accumulated as culture, because by being forced to submit to representatives of the spiritual animal, it arouses the same social desires to ward them that made individuals submit to the leader. This remedy works most effectively in the case of young offenders, who have not had a proper moral training, for in their case the offense is usually impulsive and punishment tends to strengthen the desire that inhibits acting on impulse.xcvi

Whatever of the source of the belief that it is good to be moral, the belief itself gives rational subjects a desire to be moral, because they have the desire to submit to reason. Even when being moral is contrary to individual self interest, the rational subject is able to be moral, because he are able to do what is good because he believes that it is good. What is added by ontological philosophy is an explanation of how those faulty and not wholly convincing practical arguments of traditional culture are pointing at the truth about what is good, namely, that each rational subject has a spiritual interest in being moral.

The capacity to be moral is a third way in which reason makes the subject autonomous. We have seen how the autonomy of reason enables the reflective subject to act contrary to the strongest desire at the moment. And we have seen how it enables rational subjects to pursue goals that do not control conditions that affect individual reproduction. But by recognizing that individuals have a spiritual interest, even if it is through a glass darkly, reason also makes the individual autonomous in the sense that he can act contrary to their individual self interests. When they recognize that it is good to accept the limits of morality, rational subjects can do what is morally good, because they recognize that it is good.

The desire to submit to reason is, however, felt mainly when it is not satisfied, and it feels different when one fails to live up to moral rules than when one fails to live up to one’s individual self interest. As we have seen, failure to follow the plan one has recognized to be in the interest of one’s Self arouses a special self-correcting desire, namely, shame. Shame appears as a fear of being deprived of approval or being abandoned as worthless, and thinking about its source motivates one to try harder in the future to live up to one’s life plan, though it can be intensified by public recognition of the failure, that is, as humiliation. Shame may also be aroused by the failure to live up to moral rules, but in the case of immoral actions, the failure to satisfy the desire to submit to reason also arouses guilt. Guilt appears as the fear of being forced by violence to submit, and reflecting on its cause motivates one to do what is required to be readmitted to membership in the spiritual animal.

The inevitable incoherence of rational culture. Culture is the accumulation of arguments in rational spiritual animals, and though they evolve by rational selection in the direction of natural perfection for arguments of culture, even at the end of the rational spiritual stage, the content of culture is divided by three insurmountable dichotomies. In addition to the basic difference between theoretical and practical arguments, there is the difference within theoretical reason between arguments of natural science and arguments of social science (both the science of subjects and the science of the social world) and the difference within practical reason between arguments about what is in one’s individual self interest and what is in one’s spiritual self interest.

These dichotomies are obviously surmountable, for they have been derived from spatiomaterialism as an inevitable part of culture at the rational spiritual stage. They mirror aspects of the nature of reason itself. The difference between practical and theoretical reason mirrors the two functions of input to animal behavior guidance system, representing the world so that the right kind of behavior is chosen and representing the world so that that kind of behavior can be adapted to the current situation, that is, between causing behavior and causing beliefs. The difference between natural science and the reflective sciences (psychology and social science) mirrors the difference between the understanding of efficient causes in the world of objects in space and the understanding of rational causes in the world of subjects in social roles. And the difference between individual and spiritual self interest mirrors a difference in the role of reason in guiding individual behavior and its role in guiding the behavior of the spiritual animal.

The ontological explanation of these dichotomies by the nature of reason is so obvious at this point that what is likely to be obscure is how the difference can fail to be understood. But the incoherence caused by these dichotomies runs deep, for bridging them would require an explanation of how the good depends on the true, how mind and body are related, and why individuals should be moral. These are all issues that remain unresolved even today, nearly two and one half millennia after the beginning of philosophical culture.

Without an adequate answer to these questions, culture is not fully coherent, because there is no way of integrating adequately everything that reason can know about the world as a single worldview. The incoherence of culture may not be obvious, because without a more coherent way of explaining the world, the coherence of the prevailing arguments is basically the standard by which the coherence of arguments judged. And at the rational spiritual stage, the evolution of arguments by rational selection cannot be any more coherent, because the level of organization of the arguments that are possible at in rational level culture leaves arguments, at best, clustered into the four groups entailed by the three dichotomies (that is, natural and social science and individual and spiritual interest). Appeal to a more basic principle is the only way of integrating and unifying arguments at the rational stage, and there is no principle that can adequately bridge the gaps between these clusters of arguments. Indeed, in most cultures, even arguments in each of these four clusters are far from being integrated under a single principle, for even that level of natural perfection is probably beyond the limits of cultural evolution at the rational spiritual stage.

What rational culture can do is paper over the differences among them by religion. Religion is the attempt to explain both the natural and the social world and, with the latter, the relationship between the individual and the society by appeal to gods or other entities beyond the natural world. These entities are ultimately subjects, that is, beings whose behavior is explained by reasons, and thus, it is an attempt to reduce all the arguments accumulated by culture to an argument about the behavior of a special kind of subject. Such arguments are obvious appealing. They resonate with the ancient desire to submit to a leader in the dominance hierarchy (and the child’s desire to submit to a parent or guardian). But without an adequate argument, traditional religion persists only because of the failure of culture to discover adequate answers to these basic questions.

10 Philosophical stage (Philosophical spiritual animals). For an evolutionary stage after rational spiritual animals to be inevitable, three conditions must be satisfied: (1) there must be a higher level of neurological organization than at the rational spiritual stage, (2) such a higher level must be functional in the sense of opening up an entire range of new powers to control relevant conditions that can evolve gradually over a long period of time, and (3) it must be possible for it to be tried out as a radical random variation on evolving structures under conditions in which it will be naturally selected for its power.

It is relatively easy, as it was at the previous stage, to see that the first two conditions are satisfied, for it can be known by reflecting on this ontological argument. The higher level of neurological organization is evident in the linguistic representation used to state it, and the function of philosophy can be seen in how all the arguments of rational level culture are incorporated in its explanation of the wholeness of the world, even if the plight of epistemological philosophy makes it doubtful that philosophy has a function.

This does not, however, resolve doubts about the inevitability of the philosophical stage, because ontological philosophy is hardly within the range of random variations tried out in arguments of rational spiritual animals. Such an ontological argument is possible only after epistemological philosophy has evolved, and thus, in order to show the inevitability of the philosophical stage, I will first show how epistemological philosophy is functional and, then, how it is possible, that is, how epistemological philosophy comes within the range of random variations in rational level culture as a result of a series of stages of social evolution. That will put us in a position to trace the career of epistemological philosophy and show how it makes the evolution of ontological philosophy inevitable.

The function of the philosophical level of neurological organization. “Philosophy,” or, literally, the love of wisdom, is the name usually given to arguments that depend on a higher level of neurological organization than those ordinarily exchanged in rational spiritual animals, for it is recognized that philosophy aspires to make reason fundamentally more powerful in discovering the good and the true. But philosophy is not usually explained as a higher level of organization in the arguments being exchanged as culture.

Ontological philosophy. In order to make this explanation of philosophy clear, I will use ontological philosophy to illustrate the nature and function of the philosophical level of neurological organization and then show how epistemological philosophy has a similar nature and function. That will leave us with the task of showing how epistemological philosophy and ontological philosophy are possible in the relevant sense.

Nature of the philosophical level of neurological organization.Though the ontological cause of the philosophical stage must be, according to reproductive causation, a yet higher level of neurological organization, the higher level is more readily seen in the structure of the linguistic representations it generates.

Just as the linguistic level of neurological organization was evident in the grammatical structure of natural sentences, and the reflective level was evident in the grammatical structure of psychological sentences, so the philosophical level of neurological organization can be seen in the structure of the arguments that are exchanged by members of philosophical spiritual animals. By contrast to the arguments exchanged at the rational spiritual stage, philosophical arguments have a two-step structure: they establish a foundation, and then they use that foundation to show that certain truths hold necessarily, that is, prior to ordinary arguments (of the rational spiritual stage).

In the case of ontological philosophy, the first step is an inference to spatiomaterialism as the best ontological explanation of the world, and the second step uses that ontology as a foundation for showing what holds necessarily of the world. That is, it entails ontologically necessary truths. Necessary truths require a higher level of part-whole complexity in the structure of arguments, because they hold prior to arguments at the reflective level, that is, the arguments of empirical science and ordinary moral reasoning.

Since spatiomaterialism entails necessary truths, ontological philosophy can show the validity of arguments that are characteristic of the rational stage and even the truth of some of their conclusions. It shows, for example, the validity of efficient-cause explanations in natural science and the truth of mathematics.

Furthermore, given that space and matter have natures that explain ontologically the truth of the basic laws of physics, the necessary truths of ontological philosophy include an explanation of biological and cultural evolution, and thus, ontological philosophy also shows the truth of conclusions about what is good and explains the validity of other kinds of arguments, such as rational explanations of the behavior (and beliefs) of subjective animals and the empirical method (that is, inferences to the best efficient-cause or rational-cause explanation).

The two-step argument illustrated by ontological philosophy may be said to have a higher level of forensic organization than arguments of rational level culture, because the higher level of part-whole complexity in the linguistic representations comes from the structure of the argument being made.

It indicates, in any case, a higher level of neurological organization in the brains of the rational beings exchanging such arguments, for as we have seen, linguistic representations also have a nonverbal side. Verbal behavior represents the structure of activity in the imagination of the speaker, that is, in his thinking, and since the verbal behavior of an ontological philosopher requires a higher level of part-whole complexity in linguistic schemata than at the rational spiritual stage, philosophers have what might be called “philosophical imagination.”

Ontological philosophy is, however, only one example of this higher level of forensic organization and philosophical imagination. There is another way of doing philosophy. that is epistemological philosophy, and as we shall see, epistemological philosophy plays an essential role in making ontological philosophy possible.

Functionality of the philosophical level of neurological organization. Ontological philosophy can also be used to show how such a higher level of forensic organization makes reason more powerful.

If we assume that knowing the true is a source of power for rational beings, we can see in an indirect way how the philosophical level of neurological organization can be functional, because ontological philosophy involves new form of imagination. At each level of neurological evolution after telesensory animals, the faculty of imagination has made it possible to represent a new aspect of the world, by giving subjects the capacity to see something actual (or imagined) against the background what is possible, and that is true of the philosophical level as well.

Spatial imagination enabled subjects to see the actual spatial relations of objects against the background of what is possible by motion.

Structural imagination enabled subjects to see the actual geometrical structures of objects in space against the background what is possible by manipulation.

Naturalistic imagination enabled subjects to see the actual states of objects in space against the background of what is possible by efficient causation.

Rational imagination enabled subjects to see the actual psychological states of subjects against the background what is possible by rational causation (that is, ordinary reasoning).

Likewise, philosophical imagination, as illustrated by ontological philosophy, enables subjects to see what is actual against the background of what is possible by ontological causation (that is, what is compatible with the ontologically necessary truths that follow from spatiomaterialism).

The functionality of the philosophical level of neurological organization can also be seen by comparison with the rational spiritual stage that precedes it. As we have seen, three dichotomies put a cap on cultural evolution at the rational spiritual stage, but these arguments are all united by this ontological explanation of evolutionary change and how its overall course leads to rational beings like us.

Ontological philosophy overcomes the dichotomy between theoretical and practical reason, because by explaining the good as what makes a contribution to the natural perfection that ontological philosophy implies is the direction of evolutionary change, it shows how the good is related to the true.

It overcomes the dichotomy between reflective and naturalistic understanding by explaining reason as the new kind of behavior guidance system that evolves at the reflective stage. Linguistic brains already have naturalistic understanding, or the capacity to understand efficient causes in nature, and the efficient causes of behavior (and beliefs) in subjective animals are understood as reason when the use of psychological sentences evolve, for that enables one subject to use his behavior guiding processes to simulate the reasoning of others. In both kinds of understanding, truth is explained as a correspondence between representations in the brain and aspects of the world. It is just that the representations and aspects are different in each case.

And it overcomes the dichotomy between individual and spiritual self interest, because its explanation of the evolution of spiritual animals shows how the natural perfection of both the individuals and the spiritual animal as a whole are related. Moral rules limiting the pursuit of self interest and rules of justice limiting the pursuit of spiritual interest are the balance between the good of contributing to each.

The most direct way of seeing that the philosophical level of neurological organization is functional, however, is by its implications for practical reason. The basic way that reason makes animals powerful is by guiding their behavior to control relevant conditions, and since, in rational animals, such guidance comes from discovering the good, the success of ontological philosophy in explaining the nature of goodness illustrates how philosophy can be functional. Knowing the nature of goodness, not only do we understand why things are good, but we can also tell which things are good.

We will, however, put off using this ontological explanation of the nature of goodness to determine what it is good for rational beings to purse until we have seen that all the stages leading up to ontological philosophy inevitable. See What ought to be.

Possibility of the philosophical level of neurological organization. Though the possibility of the philosophical level of neurological organization is entailed by its actual existence, that does not show that it is possible in the relevant way. What must be shown is that it is possible for a higher level of forensic organization to be tried out as a random variation on the arguments of the kind that evolve at the rational spiritual stage and tried out under conditions in which it will eventually be naturally selected for its greater power. The latter is not shown by the actual existence of ontological philosophy (which we know because we understand this argument), because it might be just a gigantic accident, or a message from some extraterrestrial intelligent beings.

There is, however, no reason to doubt that a higher level of neurological organization is possible because of limitations in the mechanism of embryological development (the multicellular biological behavior guidance system which constructs the nervous system). No genetic changes are necessary, because it is just a higher level of forensic organization in the arguments being exchanged within a spiritual animal and that can be tried out by cultural evolution alone.

Arguments with a higher level of neurological organization than rational level culture can be constructed and understood by brains with a faculty of rational imagination, because they are just arguments made from a higher foundation showing that certain truths hold necessarily (and explaining the validity of ordinary arguments). That does not require a higher level of grammatical structure, because the difference between a philosophy’s foundation and its necessary truths is described using linguistic representations on the level of natural and psychological sentences. Or if you will, talk about “philosophical foundations,” “necessary truths” and the like are a new kind of grammatical marker, one that is used explicitly to organize other sentences in a two-step argument of the kind suggested above. All it requires is a more complex linguistic behavioral schemata in the prefrontal neocortex, where behavioral schemata are stored for use by the behavior generator.

The philosophical level of forensic organization involves, therefore, a kind of level of neurological organization that can be tried out by a random variation on the arguments that are evolving in culture at the rational spiritual stage. It is just a way of uniting all the arguments of rational level culture that is basically different from religion (the way used in rational level culture). When such a philosophical linguistic act is tried out in one brain, it is possible for other brains to acquire the schema, so that they can generate the philosophical argument for themselves (because the behavioral schema can evolve in their brains by reinforcement selection, that is, by internalizing the linguistic structures being exchanged). And if it increases the coherence of their worldview, it will be rationally selected and, thereby, evolve in the culture of a spiritual animal.

Thus, philosophical imagination can evolve by rational selection within a spiritual animal (though cultural evolution is always backed up by the natural selection of the spiritual animals involved). Since only rational imagination is needed to learn philosophical arguments, the brain can acquire the higher level of neurological organization from the culture, without further biological evolution (except possibly increased efficiency in exercising powers that have already evolved, or what is called “intelligence”).

All that is required for the philosophical level of neurological organization to evolve, therefore, is that a linguistic representation with a higher level of forensic organization be tried out as a random variation on the arguments that are being exchanged at the rational spiritual stage and that it be functional in the sense that it makes the worldviews of rational subjects more coherent. (Furthermore, the philosophical spiritual animal must be at least as powerful as it was before, if not more powerful.) Given what we know about rational spiritual animals, however, that may see quite doubtful. There are two kinds of reasons.

First, in order for a higher level of forensic organization to evolve, the first level arguments of rational culture must approach, at least, natural perfection for arguments of their kind. In discussing the dichotomies of rational culture, we simply assumed that cultural evolution had reached natural perfection for such arguments, because what was relevant were the limitations that would be encountered even at that point. But any such cultural evolution would take a long period of time spanning many generation. Cultural evolution is sustained by spiritual animals, but it requires a spiritual animal that fosters the exchange of arguments, provides enough member with the leisure to argue at length about matter far removed from immediate practical needs, and in which writing has evolved to preserve a record of the exchange of arguments from one generation to the next. None of those conditions are likely to hold in nomadic bands.

Second, even if such conditions were to obtain, it would not make ontological philosophy possible, at least, not completely enough for it to be convincing. Ontological philosophy also depends on modern science, if only because there would be no way of tracing the course of evolution without physics, molecular biology and neurophysiology. And without the capacity to explain evolution and to trace it overall course, there would be no explanation of the nature of goodness, no explanation of the difference between naturalistic and reflective understanding, and no explanation of the validity of rational-cause explanations.

Physics depends on the use of mathematics, because it infers to the best efficient cause explanation by making quantitatively precise predictions about the world. And mathematics is not enough by itself, because molecular mechanisms cannot be understood without the technology to experiment on the micro level processes. Judging from history, therefore, natural science also seems to depend on an economic system, like capitalism, which sponsors it by exploiting the technology that science makes possible and thereby evolving the technology that science itself needs to test its theories empirically.

Since neither mathematics nor capitalism can evolve at the rational spiritual stage, its naturalistic explanations inevitably lag far behind modern science. Thus, it may seem that at the rational spiritual stage, the only way of knitting all the arguments of culture together is religion, or the explanation of the world by appealing to the reasons that motivate gods or immaterial spirits. But that is just a myth, not a higher level of forensic organization.

Another stage of evolution is nevertheless inevitable, because there is something that makes it inevitable that cultural evolution at the rational spiritual stage will approach nature perfection and there is an easier way of constructing an argument with a higher level of forensic organization than ontological philosophy.

Rational level culture does eventually evolve far enough to approach natural perfection for arguments of its kind, because there are, in addition to stages of cultural evolution, stages of social evolution. There are higher levels of part-whole complexity in social structure, and since each makes spiritual animals more powerful in winning wars, there is a series of stages of social evolution that leads from nomadic bands of rational subjects to civilizations. Since civilization is able to foster and sustain the exchange of arguments over sufficiently long periods of time, there are inevitably rational spiritual animals rational in which culture eventually approaches natural perfection for arguments of its kind.

In such civilized societies, it is possible for a higher level of forensic organization to be tried out as a random variation on arguments evolving in rational level culture and be rationally selected for its coherence, because there is an easier way to construct such an argument. That is epistemological philosophy.

Though this second level of forensic organization is unable to defend itself against skeptics in the end, it brings enough coherence to the worldviews of rational beings for epistemological philosophy to be rationally selected and philosophical level culture to evolve. Thus, it is possible for mathematical arguments to evolve and for capitalism to evolve, providing the conditions under which modern science can discover the truth about the micro structure of the natural world. That makes it possible for a form of ontological philosophy that can explain the validity of all the kinds of arguments of rational level culture to be tried out as a random variation on the arguments of philosophical level culture.

Epistemological philosophy. From the beginning of this ontological philosophical argument, I have occasionally digressed to take epistemological philosophy into account by suggesting its critique of epistemological philosophy. But at this point, epistemological philosophy turns up as part of the argument itself, as the first convincing attempt to construct an argument with a higher level of forensic organization, and so I must explain how it is also a philosophical level of neurological organization that is functional, even though it is basically different from ontological philosophy.

Epistemological philosophy, like ontological philosophy, involves an argument with a higher level of part-whole complexity from those of the rational spiritual stage. It also makes a two-step argument, by first establishing a foundation from which to support arguments about what is necessarily true. But instead of taking as its higher level foundation an ontological explanation of the world, it uses a theory about the nature of reason.

Already at the rational stage, there is a way of organizing arguments as parts of larger arguments, for as we have seen, principles evolve which state a reason for some kind of conclusion about what to do or what to believe covering an entire range of similar situations. But epistemological philosophy is not merely the discovery of a more general principle to be used as premise in a first level argument. Rather, it introduces a new kind of reason, which supports the arguments of rational level culture. The first step of epistemological philosophy is, therefore, to defend a theory about the nature of reason based on reflection, and the second step is to use it to explain the validity the ordinary, first-level arguments of rational culture.

By “reflective understanding,” I mean the use of the faculty of rational imagination to explain how rational subjects draw conclusions about what to do or what to believe by the reasons that cause them, that is, the understanding of rational causation. That is how epistemological philosophers use rational imagination to reflect on how we know.

But it should be distinguished from the implicit role of rational imagination in talk about reasons and conclusions in general, in which the subject who has the psychological state is anonymous. The latter is part of naturalistic understanding, at least, at the rational spiritual stage, because natural scientists talk about the reasons for their conclusions, for example, when inferring to the best efficient-cause explanation of some observed phenomenon. It is also part of reflective understanding, because psychologists and social scientists also talk about the reasons for their conclusions, for example, in inferring to the best rational-cause explanation of someone’s behavior. But in reflective understanding, the conclusions themselves are also about reasons as psychological states that occur in subjects, for they are explanations of the beliefs or behavior of subjective animals.

Reflective understanding is the foundation for the theories about the nature of reason that are used as the foundation for epistemological philosophy. Indeed, it is usually reflective understanding of one’s own cognitive processes, or self-reflection, that provides the foundation for epistemological philosophy. To make this distinction explicit, I will continue to use “reflective understanding” (or “subjectivistic understanding”) to refer to the way of explaining the beliefs and behavior of subjective animals, and reserve the term, “reason,” for the more general, implicit use of rational imagination in talking about the reasons for conclusions (as in stating arguments explicitly) regardless of the subject matter of those conclusions.

Reflective understanding makes various theories about the nature of reason possible, as we shall see when we trace the career of epistemological philosophy, but in each case, the theory about the nature of reason entails the validity of (most) arguments of rational level culture. That is, it either justifies the truth of their conclusions, by showing how such arguments lead to the discovery of the true, the good and the beautiful, or entails conclusions directly, as the necessary truths of epistemological philosophy. Both implications are parts of the second step of its two step-argument.

As we have seen, dichotomies inherent in the arguments accumulated as rational level culture inevitably show up as gradual cultural evolution approaches natural perfection for arguments of their kind. Rational subjects feel the need for an argument to overcome them and unify their understanding of the world, though they may not realize that what they are looking for is a higher level argument.

The three inevitable dichotomies divide arguments into at least four clusters, and no principle of the kind that evolves at the rational stage enables reason to integrate and unify all the arguments by which it knows about the world into a single argument, at least, not into one that can stand up under rational scrutiny.

From our ontological vantage, the inevitable limitations in the power of reason at the rational spiritual stage are obvious, because we have seen why there are unbridgeable dichotomies among the arguments accumulated as rational level culture. Those dichotomies are inherent in the nature of reason as the behavior guidance system that evolves at the rational spiritual stage, and as long as the only way of integrating and unifying the arguments accumulated as culture is by the evolution of more general principles of the same kind, there is no obvious solution — except traditional religion.

Religion is a way of papering over these dichotomies at the rational spiritual stage. But the underlying limitation can still be felt by those versed in the arguments accumulated as rational culture. To them, it will be obvious that, given how religion attempts to explain everything in the world as part of a single system (and, thus, to unite all the arguments of rational level culture and), different religions would work just as well. Religions all attempt to explain everything by appeal to gods or spirits in some way, that is, by using a rational explanation of the behavior of some nonhuman being to explain the natural world (including why there are human beings and the nature of the good they are pursuing). But when a religion is seen against the background of other possible religions, there is no reason to prefer one religion over the others, because none stands out as inherently more coherent (though, of course, less cosmopolitan thinkers will prefer their own religion simply because of its familiarity). With no way to choose among religions, those who sense the lack of unity about rational culture have a motive to look elsewhere.

The three dichotomies are, however, only the most obvious limitation on the evolution of arguments at the rational stage. Rational culture is also limited in other ways, most obviously to us, in natural science, that is, in the explanation of efficient causes in nature. Though the naturalistic understanding afforded by their culture may include a highly evolved technology for extracting resources from nature, protecting themselves from hazards, and fighting wars, reflective subjects are still very much at the mercy of natural forces they do not fully understand. Religious explanations of natural phenomena do not give them the power they seek, and that is another motive for looking for a new kind of argument.

Under the right conditions, as we shall see, it is possible for a random variation on the arguments of rational culture to try epistemology as a way of organizing the arguments of rational culture at a higher forensic level.

Epistemological philosophy starts its higher level argument by reflecting on how the subject knows the true, the good and the beautiful. That is the first step of its two step argument. It offers a theory about the nature of reason and how it is situated in the world in order that can explain why the arguments of rational level culture are valid. That second step would overcome the dichotomies that limit rational level culture (as well as the inadequacies of natural science) by showing how all the various arguments accumulated as rational culture are various parts of a single argument about the nature of reason.

The difference between epistemological and ontological philosophy comes, therefore, from the difference between reflective understanding and naturalistic understanding (or the dichotomy among arguments of rational culture that comes from the two, basically different kinds of causes that are represented explicitly as causes in the faculty of rational imagination). Instead of starting with reason’s naturalistic understanding of the natural world and using a theory about the nature of substance to offer a deeper explanation of its efficient causes, as ontological philosophy does, epistemological philosophy starts with reason’s reflective understanding of individual subjects (and the social world) and uses a theory about the nature of reason to offer a deeper explanation of rational causes.

That is, by describing a “cause” that explains the nature of all kinds of reasons at work in the arguments of rational culture, epistemological philosophy proposes to show how reason is able to know everything that can be known, including the natural world. This second order argument justifies first level arguments about the true, the good, and the beautiful, and what follows directly from it are necessary truths, because they are truths that can be known prior to making first level arguments of any kind.

Epistemological and ontological philosophy overcome the dichotomy between naturalistic and reflective understanding from opposite directions, because they use opposite kinds of understanding in the first step of their two step argument to formulate a theory about a deeper cause of everything knowable by rational beings.

To be sure, ontological philosophy also has a theory about the nature of reason that explains the validity of all the (valid) first level arguments of rational culture. But it defends that theory by first explaining the validity of the efficient-cause explanations of natural science, as a form of rational level culture, on the basis of a theory about the nature of the substances that constitute the natural world. (Indeed, prior to explaining the nature of reason, ontological philosophy has already explained two of the dichotomies, the difference between the true and the good and the difference between the individual and spiritual interest.)

Thus, ontological philosophy explains why natural science is true in a way that can also explain why there is such a thing as science in the world, whereas epistemological philosophy explains why there is such a thing as science in a way that also explains why natural science is true.

Epistemological philosophy is credible enough to sustain a long period of cultural evolution, and as we shall see, it does increase the power of reason to discover the true, the good and the beautiful. For example, it fosters the evolution of mathematics and, thus, makes modern science possible. It also provides a culture in which capitalism can evolve, and capitalism sponsors the evolution of modern science.

Epistemological philosophy does not ultimately succeed, however, in explaining the validity of all the arguments of rational level culture, because it encounters problems it cannot solve. Its theory about the nature of reason ultimately involves a dualism of some kind that undermines its justification of rational level culture and leads to skepticism about the philosophical theory itself.

The problems of epistemological philosophy are especially intractable, as we shall see, because of how subjectivistic understanding fits together with the nature of consciousness. Since epistemological philosophy constructs its theory about the nature of reason on the basis of what is known about reason by reflection (that is, on reflective understanding), its theories of reason all ultimately depend on taking certain representations that occur in rational imagination as basic and, thus, beyond doubt. Those representations have a phenomenal appearance for the subject, because the rational subjects who understand epistemological arguments have brains that generate photons whose intrinsic natures mirror activity throughout the cerebrum. Since the content of the representations in their brains on which they are reflective is mirrored in those phenomenal properties (the intrinsic natures of the photons continually generated by the active brain), it is easy to assume that those phenomenal properties are a form of intuition in which objects are known simply because of how they are present to the subject. Thus, epistemological philosophy takes reason to depend on intuitions of some kind, and the problems to which intuition-based theories of reason lead give rise to new theories about the kinds of objects of which consciousness is the intuition.

Consciousness plays a role in making epistemological philosophy plausible, but that does not mean that phenomenal properties are the cause of anything that happens. It is rather that consciousness either makes it easy to overlook the difference between consciousness and what really exists (that is, naïve realism), so that what makes it easy for epistemological philosophy to seem to unite all the arguments of rational level culture is leaving a basic aspect of the actual world out, or else it recognizes the difference and faces the intractable problem of mind-body dualism. (See Change: Global regularities: Reproductive causation: Revolutionary change: Subjective stage (6): Unity of mind.)

Even though epistemological philosophy does not ultimately succeed in doing what it tried to do, it also shows how the philosophical level of neurological organization is functional, in the sense of opening up an entire new range of powers to control relevant conditions. Thus, if it can be shown that epistemological philosophy will eventually be tried out as a random variation at the rational spiritual stage, we can already see how ontological philosophy can turn out to be inevitable.

The possibility of ontological philosophy. Epistemological philosophy plays, however, an essential role in the evolution of ontological philosophy, because it provides the conditions under which a random variation trying it out will be rationally selected for its greater power to serve the interests of reason.

Though epistemological philosophy can serve as a model for the higher level of forensic organization of philosophical arguments, that is not its only contribution to the evolution of ontological philosophy, if it helps at all.

Such a model of philosophical argument is not necessary, because when the need for a nonreligious way of fitting together all the arguments of rational culture is first felt, the simplest and most obvious way of trying to unify them is to formulate an ontological argument. Naturalistic understanding seems more complete and coherent than reflective understanding, and the religious explanations they are trying to avoid are the most obvious way of using reflective understanding.

Indeed, that is how philosophy evolved in Western culture. The validity of ontological-cause explanation was first recognized by the Pre-Socratic philosophers in ancient Greece, and as we shall see, their attempts to infer to the best ontological-cause explanation even led to the discovery of spatiomaterialism. The ancient atomists discovered that the best explanation of basic aspects of the natural world, including change, requires two opposite kinds of substances, atoms and the void. Thus, they discovered necessary truths about change and could explain some of the most basic efficient-cause explanations are true.

But without natural science, atomism could not explain the nature of reason ontologically. Thus, it could not explain everything about the world well enough to overcome the dichotomies of culture at the rational spiritual stage and show the validity of its arguments. That requires a deeper understanding of the nature of matter, molecular biology and neurophysiology, because it depends on deriving the reproductive global regularities and tracing the inevitable stages that define the overall course of evolution.

On the contrary, ontological philosophy was the model for epistemological philosophy. Pre-Socratic philosophy inspired ancient Greek confidence the in the power of reason to explain everything in the world, and as we shall see, that led to Plato’s attempt to use an epistemological foundation to show the validity of ordinary arguments about what to believe and what to do.

It might even be argued that, far from being a model for ontological philosophy, epistemological philosophy has discouraged ontological philosophy. Philosophy has come to be so closely identified with epistemological philosophy that any argument about the validity of arguments whose foundation is not a theory about the nature of reason (which relies on intuition in some way) does not seem to be a philosophical argument at all. Since there seems to be other way of doing philosophy at all, the failure of epistemological philosophy seems to be the failure of philosophy as such, which leads to the relativism discussed in the introduction. (See the Inside-Out Encyclopedia.)

The necessary contribution that epistemological philosophy makes to the evolution of ontological philosophy is, as I have suggested, natural science. Besides establishing a culture in which there is enough respect for reason to give a hearing to the arguments of individuals who are dissenting from what people generally think they know, it provides at least to essential ingredients for the evolution of natural science: mathematics and a capitalist economic system.

Epistemological philosophy fostered the evolution of mathematical arguments, because mathematics was the prime example of its deeper understanding. Without mathematics, physics would not have been able to discover the quantitatively precise laws by which it sees beneath the surface of perceptual appearances to the nature of matter. And without physics, the rest of modern natural science would not be possible.

Epistemological philosophy also provided the resources that natural science needs to evolve, by making the evolution of capitalism possible. It convinced rational subjects that morality has a rational foundation and that they are responsible for doing what is good, and that fostered the evolution of institutions that can be rationally justified and that treat individuals as autonomous agents.

Ontological philosophy is a different way of doing philosophy from epistemological philosophy. As the Pre-Socratics saw, it is possible to start with naturalistic understanding and formulate a theory about the kinds of substances constituting the world and to use that as a foundation for proving necessary truths, such as mathematics and the principles of local motion and local action, and for explaining the validity of ordinary arguments, such as the efficient cause explanations of natural science. However, given what is known by contemporary natural science about the nature of matter, evolution, molecular biology and neurophysiology, it is also possible to explain evolutionary change ontologically and to trace the stages of the overall course of evolution that lead to the existence of beings like us.

Ontological philosophy also unites all the arguments of rational-level culture as parts of a single argument. Though that includes overcoming the three dichotomies of rational level culture, ontological philosophy does it in a basically different way. The dichotomies are not overcome by its theory about the nature of reason, but rather by explaining how the stages of evolution lead up to reason. Indeed, its explanation of the nature of reason is what shows that the three dichotomies are inevitable in rational level culture.

The dichotomy between theoretical and practical reason derives from the nature of the multicellular animal behavior guidance system. The animal system of representation (and forms of intuition based on it) are the foundation of the correspondence involved in truth, and it also discovers the good, because the goal selection system use those animal representations to guides behavior to goals that contribute to the natural perfection of animals of its kind.

The dichotomy between individual and spiritual self interest derives from the nature of spiritual animals, for it is an evolutionary stage at which living organisms are imposing natural selection on themselves at two different levels of biological organization at once, the individual level and the social level. The natural perfection toward which gradual change proceeds in spiritual animals involves a balance between the good of the individual and the spiritual animal, and that is what rational level culture discovers as moral arguments evolve (involving, as we have seen, limits on both individual self interest and spiritual self interest).

The dichotomy between naturalistic and reflective understanding derives from the nature of the new behavior guidance system that evolves at the rational spiritual stage. The power of reason to guide behavior comes from the evolution of arguments by rational selection, and that mechanism depends on the capacity for reflection that evolves in linguistic brains (with naturalistic understanding) as they acquire the use of psychological sentences. Thus, reflective understanding of subjective behavior is implicit in the nature of reason. This is the only dichotomy that depends simply on the nature of reason, rather than on how the essential nature of reason is determined by the nature of the stages leading up to it.

Thus, instead of trying to overcome the dichotomies by explaining how reason is whole, it is possible to bridge the gaps between clusters of arguments in rational culture by first explaining how the world itself is whole. The wholeness of the world is explained ontologically, that is, by showing how everything that exists in the world is constituted by substances. That is what the Pre-Socratics tried to do, and the reason that such an obvious kind of argument can prove necessary truths that are not already recognized is, as we have seen, that natural science does not recognize space as a substance. The wholeness of space is itself an ontological cause of the wholeness of the world, and by taking it into account and showing how the world is constituted by two opposite kinds of basic substances, everything in the world can be explained in a more complete way. As we have seen, that has many profound implications.

Natural science entails an ontology, as we have seen, but since it infers only to the best efficient-cause explanations, not to the best ontological-cause explanation as well, physics gets along without recognizing that space is a substance. It is a consequence of the empirical method of science (though the oversight may be reinforced by the skepticism to which epistemological philosophy had led). In any case, since spatiomaterialism can explain ontologically why the basic laws of physics are true, ontological philosophy can assimilate the conclusions of natural science, and thus, it is in a position to show how the course of evolution is inevitable in a spatiomaterial world like ours. By tracing the inevitable stages of evolution, it not only overcomes, but shows the inevitability of the dichotomies of rational level culture. Since the stage at which reason evolves determines its essential nature, ontological philosophy has an explanation of the nature of reason that is able to explain the validity of all the kinds of arguments used at the rational spiritual stage, including not only natural science but also psychology and social science, albeit in a different and deeper way than epistemological philosophy.

It is important to keep in mind, however, that the truths about the course of evolution are ontologically necessary only if this is a spatiomaterial world in which matter and space have a nature that can explain the truth of the basic laws of physics and give the universe the kind of large scale structure it has. Since some aspects of those laws are contingent, relative to spatiomaterialism itself, what ontological philosophy has proved about the inevitability of the course of evolution are only conditional ontologically necessary truths. But assuming that space and matter have such a nature, the stages of evolution are inevitable, because as we have seen, the reproductive global regularity about revolutionary change is among those truths. New evolutionary stages are inevitable when higher levels of part-whole complexity in evolving structures are both functional and possible. Thus, the same deeper cause that explains why the efficient cause explanations of naturalistic understanding (and natural science) are true also explain the existence and nature of the rational beings who know the true, the good and the beautiful.

In order to be a complete explanation of the world, however, ontological philosophy must also explain epistemological philosophy. We shall see in the next section what makes the evolution of epistemological philosophy inevitable, and we shall trace how the gradual evolution of epistemological philosophy leads to ontological philosophy. But beings like us would not understand fully what makes epistemological philosophy so plausible and its problems so intractable, unless ontological philosophy also explained the nature of consciousness. Consciousness is what makes it so easy to take for granted that reason is based on some sort of intuition.

All that ontological philosophy needs to explain the nature of phenomenal properties is its assumption about the basic nature of substance, for they are explained as the intrinsic natures of bits of matter (whether or not space is a substance). But since bits of matter do coincide with substantival space, there is a form of matter that can explain the complex phenomenal properties of conscious rational beings like us. Active brains are continually generating photons whose extrinsic natures suggest that activity throughout the cerebrum must somehow be registered in the intrinsic natures, and thus, it can explain the peculiar unity of mind that gives the representations in rational imagination an appearance to the rational subject.

Thus, even though ontological philosophy entails is a form of epiphenomenalism about phenomenal properties, which denies that phenomenal properties are efficient causes of what happens, it can identify the role that consciousness plays in the mistake about the nature of reason that lies at the foundation of epistemological philosophy. Phenomenal appearances are not intuitions of objects, at least, not of the kind that epistemological philosophy needs for its theories about the nature of reason, but just the intrinsic natures of certain bits of matter generated by the brain. It is the faculty of imagination built into the brain that makes knowledge of the world possible.

In sum, epistemological philosophy plays an essential role in making ontological philosophy possible. It is a phase in the gradual evolution of arguments at the philosophical spiritual stage that leads ultimately to ontological philosophy and eventually to the natural perfection of philosophical level culture. It is part of a change that would occur on any planet where life evolves at all in a spatiomaterial world like ours.

The philosophical stage is the final stage in this series of stages in the evolution of spiritual animals, because when it is complete, there is no way for a yet higher level of forensic organization (a higher level of part-whole complexity about linguistic structures) to increase the power of reason in any basic way. Reason is a behavior guidance system, and since it will know, at the end of the philosophical spiritual stage, how the world is whole and it will have followed out its implications, including the entire course of evolution, it will already know everything about the world that can be known by reason (except for contingent truths), including everything about the nature of goodness and beauty. Philosophical reason will already do everything that a behavior guidance system can do to control relevant conditions in a spatiomaterial world like ours.

Thus, we might even that the very function of philosophy is to explain the wholeness of the world in the complete way as ontological philosophy does. Knowledge of that wholeness is the wisdom that philosophy loves, though it has not been able to describe it in this way. When rational beings know how the world is whole, they have a new way of knowing what is true, good and beautiful, because there are necessary truths about them, including a justification of the validity of (most) first level arguments, based on perception and desire, by which contingent truths are known.

That is not to say that there are no further stages of evolution. There are many series of stages of evolution, and what we have been following out is merely the series that leads up to rational being like us. We have not considered the stages in the evolution of plants or other minor series of stages that may occur within the stages identified here. And philosophical spiritual animal may go through evolutionary stages of other kinds, such as those involving economic production, the use of technology, and inhabiting the rest of the solar system. What comes after ontological philosophy is discussed in the final three chapters on What ought to exist.

The possibility of philosophical spiritual animals. Though the nature and function of the philosophical level of neurological organization is clear, the inevitability the philosophical spiritual stage of evolution is still in doubt, because it is not yet clear how epistemological philosophy can be tried out as a random variation on the arguments of the rational spiritual stage and tired out in a way that allows it to be selected for the power it affords.

Culture must evolve long enough at the rational spiritual stage for a second level of forensic organization to be tried out as a random variation, and that means that some rational subjects must be free enough from the immediate demands of survival to exchange arguments over many generations. It also requires writing and a love of argument — writing in order to bridge the gap between generations, and love of argument to spend the time and effort required to sort out which arguments yield the most coherent world views. These conditions can be provided in what is called civilized society. Thus, in order to show the inevitability of the philosophical spiritual stage, I need only show the inevitability of civilization, for we can assume that among the variety of civilized spiritual animals that would come to exist on the surface of a planet if they were inevitable, there would eventually be some in which epistemological philosophy would be tried out as a random variation in cultural evolution.

There is, as it turns out, an aspect of spiritual animals that would make civilized society inevitable, because the social aspect of spiritual animals can also have a structure that is capable of several levels of part-whole complexity. That is, levels of social organization would cause a series of stages of social evolution, and assuming that civilization is one of these levels, civilization would have an essential nature just like what evolves at any stage of evolution. And the overall course of evolution would be determined by how the series of stages of social evolution combines with the series of stages of cultural evolution that we have been discussing (that is, the spiritual stages of evolution that we are following, primitive, rational and philosophical, respectively).

Even in civilized society, however, epistemological philosophy is unlikely to be tried out, unless the more obvious ontological approach to philosophy has been tried out and found wanting. The inadequacy of religious attempts to unite the arguments of rational level culture in a compelling way is the only plausible reason to try constructing linguistic structures with a higher level of forensic organization, and since the world seems to be a natural world, the initially most plausible way of explaining everything in the world will be to identify the substances constituting it. Thus, the evolution of epistemological philosophy requires the culture of a civilized society in which dissatisfaction with religious explanations has spurred the development of a primitive form of ontological philosophy.

There was, as it happens, a spiritual animal at the civilized social stage of evolution in which ontological philosophy was tried out, namely, ancient Greece, and that is where we will find the origins of epistemological philosophy.

Stages of social evolution. Spiritual animals have a social aspect, as well as a cultural aspect, as part of their essential nature, and both are structures of the spiritual animal as a whole, though these structures are fundamentally different from one another. These aspects arise from how language is used to guide their behavior. The original social aspect is the fact that the members of spiritual animal are in continual linguistic interaction with one another, and the cultural aspect is all the linguistic structures that are, in principle, complete in the brain of each members. The use of language to distribute a plan is what coordinates the behavior of the members of spiritual animals in social level behavior, and higher levels of organization in the cultural structure distributed by language is what causes the stages in the evolution of spiritual animals that we have been describing. At the rational stage, as we have seen, the shared plan takes the form of mutually accepted rules (or arguments) governing social roles, and the social level behavior is just the existence of institutions.

Though institutions that persist over long periods of time may be considered a kind of “social structure” of the spiritual animal, they are not the kind of structure that can serve as a structural cause of the spiritual animals behavior. Institutions do not give the spiritual animal a geometrical structure that does not change over time. They give the social aspect of spiritual animal a spatio-temporal structure, for institutions are just a form of social level behavior that is generated by the cultural aspect. (This is, perhaps, most obvious in the case of economic institutions. Although they involve patterns in the interactions of members, they also include the social level behavior by which spiritual animals extract free energy and other resources from nature, just like any animal acting on other objects in space.)

Spiritual animals are, as we have seen, different from multicellular animals (with nervous systems), because their animal behavior guidance system is not constructed by coordinating the behavior of the lower level organisms. Since its behavior is guided by the exchange of linguistic representations, no social structure is needed, except continual linguistic interaction, and its animal behavior guidance system also serves as its biological behavior guidance system for this social level animal.

The reason for calling this kind of social level animal a “spiritual animal” was that, unlike all other animals, it does not need any unchanging geometrical structure as a whole. The spiritual animal has no body except the bodies of its members. That gives the spiritual animal enormous power. Since the parts of its body can have any geometrical structure that is possible for objects in space that move as time passes, there is no limit on the spatial aspects that its animal behavior can have in acing on other objects in space. For example, when members coordinate their behavior to herd deer into a trap, they are like a giant animal in relation to their prey.

However, the lack of any essential geometrical structure to the spatial aspect does not mean that spiritual animals cannot acquire a geometrical structure of a kind that can serve as a structural cause of social level behavior.

There is a way in which institutions can sustain a geometrical structure under the social aspect that would serve as a structural cause for helping to generate the behavior of the spiritual animal. That is the institution of property, for when it includes the ownership of parcels of land, it can impose an unchanging geometrical structure on the spiritual animal as a whole. As members observe the rights and duties defining the social roles of property ownership, the spiritual animal has, as least, an unchanging geographical structure.

Let us use the term ,“social structure,” to refer to what is unchanging about the geometrical structure of spiritual animal, reserving the term, “institution,” for patterns in the behavior of the members of spiritual animals that do not necessarily have an geometrical structure that does not change over time. Thus, social structures would include the geographical structures of spiritual animals with the private ownership of land. But there are also other kinds of social structures, as we shall see, which depend on a geographical structure, and they can, in a sense, be considered social structures with a higher level of part-whole complexity.

To be sure, nomadic spiritual animals also have a structure under their social aspect. But apart from its institutions, it is merely how the members are merely in continual linguistic interaction with one another, and so, let us speak of nomadic spiritual animals as having only a “spiritual social structure,” the minimal structure required by the essential nature of spiritual animals.

Levels of social structure. The possibility of spiritual animals having social structures of a kind that can serve as structural causes of social level behavior means that stages of social evolution are possible. If there is a series of levels of part-whole complexity involved in social structures, they can evolve in only one order, from one level to the next. And their evolution will be inevitable, if in each case, the higher level social structure is both functional and possible — that is, “functional” in the sense of generating social level behavior that helps control conditions that affect the spiritual animal’s reproduction, and “possible” in the sense of being a possible random variation with such effects, given the institutions that are evolving in the spiritual animal. Thus, if they lead up to civilization, they will show the inevitability of philosophical culture. Thinking of social structure in this way, there are at least three stages of social evolution during the rational spiritual stage — and another stage of social evolution that is eventually made possible by philosophical culture.

Nomadic bands. This is the stage of social evolution at which we left the history of the evolution of rational spiritual animals, the stage whose limited resources and leisure posed a problem about the possibility of philosophical culture. Though members of spiritual animal are in continual linguistic interaction and they generate institutions as social level behavior, they do not have a geometrical structure as a whole, because they are always picking up and moving from one place to another in order to hunt and gather food. Their size is limited (from twenty five to maybe as many as a hundred) by the amount of food that can be acquired in this way. This is the stage during which the cultural evolution of moral rules would lead most easily to equality among members.

Agricultural villages. When environmental conditions became favorable (it happened about 11,000 BC in the Middle East at the end of the last ice age), some nomadic bands would give up hunting and gathering in favor of agriculture. The cultural evolution of natural science in nomadic bands would afford them enough knowledge of the efficient causes involved in plant growth and animal behavior to try out such an economic institution. In addition to being possible, it would be functional. The use of agriculture would provide so much more food that it would be possible for a spiritual animal’s population to grow without it having to divide into smaller groups (though that would continue to happen by setting up colonies), and so it would be naturally selected because of the advantages of increased population in fighting wars. Though such rich, sedentary spiritual animals would be easy targets for marauding bands, they could muster armies and construct defenses to protect themselves.

As population is grew, however, an increasing division of labor would be required to grow plants and take care of animals, and the institution that would inevitably evolve to coordinate their behavior in this activity is property, that is, ownership by different members (families) of different parts of land in their territory. Though there would be public areas and roads connecting different parcels of land, private ownership of land would be an unchanging geometrical structure of the spiritual animal. It would usually be stable over long periods of time, since the simplest way to assign new members to parts of land is by inheritance from parents (though the kinship would have to be adapted to provide for inheritance as members married outside their family). And it would be the foundation for the evolution of a higher level of social organization: class structure.

Civilization. The advent of agriculture would make it possible to accumulate great wealth, not only food, but other objects, both natural and manufactured, that are useful in some way. In some cases, so much food would be provided so reliably that the population increase would make it possible to sustain markets, cities, great differences in wealth, and large standing armies. With population growth, it would become necessary to protect property from theft, to extract property from individual to sustain public institutions, including a government, judicial institution, army, and religious institution, and more generally, to coordinate the behavior of the members of a spiritual animal that was spread out widely over the land. Those spiritual animals that happened on a variation on the institution of property that could sustain a class structure would tend to be larger, more stable, and better able to win at war, yielding so-called civilization.

One form of class structure is slavery, that is, the ownership of other rational subjects. This variation would probably be tried out only when spiritual animals could sustain standing armies. One of the spoils of victory in war would be slaves, and a standing army would provide a sufficient level of coercion throughout the society to ensure the dominance of masters over slaves.

Another form of class structure is feudalism, with many varieties. In Western history, it involved a difference between two classes of society in their property rights to the same parcels of land. Both classes had the right to live on the land and consume what was produced there, but one class supplied the labor for agriculture and productive activities, while the other class coordinated their behavior and protected the direct producers from foreign armies. Feudalism was not mere coercion, because the lord and the serf shared the same culture, and the mutual acceptance of its arguments required them to acknowledge one another’s rights and duties. But members of different classes did not intermarry. Class membership was inherited.

There are other forms of class structure, some involving several castes on the model of feudal class systems, and slavery can be combined with them. But there is no need to insist on any order in their evolution. In all such spiritual animals, class structure is sustained by different forms of ownership of the land on which the members live and interact with one another. That is how their social level behavior is generated. Class structure involves a relationship of domination and submission between members of different classes, and that makes it possible to coordinate the behavior of an enormous population over the whole territory occupied by the spiritual animal. Such a class structure is a higher level of part-whole complexity in social structure, because the institution of property sustains a difference between two classes of member everywhere throughout the territory.

The class structure of civilized society would make their evolution inevitable. They would be naturally selected at the social level by success in war because of the advantage of having a large population. Thus, there are three stages of social evolution leading to civilization, making it inevitable. And since class structure makes it possible to sustain a large population over a wide territory, such spiritual animals can provide the condition required to try out a higher level of forensic organization as a variation on the arguments being exchanged at the rational stage. Civilizations will tend to provide the writing needed to retain arguments over many generations and communicate them over wide areas, because writing evolves, if only to keep track of the taxes required to support the government and its allied institutions. Since there will be some members with the leisure to argue, all that is required for philosophical culture to evolve is a culture that fosters the love of argument and has respect for the kinds of judgments about rational coherence on which cultural evolution depends — except, of course, for a random variation that tires out a higher level of forensic organization involved in philosophy. We will trace the career of that stage of cultural evolution. But first, let us consider a variation on the class structure of civilized spiritual animals that will be relevant in that career.

Capitalist class structure. There is another stage in social evolution that helps make the evolution of ontological philosophy possible. Though it is just a form of the class structure that is characteristic of civilized societies, it not only sustains an even larger population than slave or feudal societies, but also contains a form of evolution by reproductive causation that leads to the evolution of increasingly powerful ways of producing food and other useful objects. I am referring to capitalism. It can be tried out as a random variation, as we shall see, only in spiritual animals with a philosophical level culture, that is, where epistemological philosophy has evolved, and since capitalism plays an essential role in making ontological philosophy inevitable, it is relevant here to describe the nature of this social structure. Then we will go back and take up the issue about the evolution of philosophical culture.

Capitalism is an economic system in which processes of production are set up when capitalists put forth the capital to purchase labor power and other commodities required to produce commodities of some kind and they then sell them on the market for a profit.

Capitalism is a class system, because members of the spiritual animal engage in such processes of production in two, fundamentally different ways: as capitalists, who put forth their money to earn a profit, and as workers, who sell their labor power to the capitalist to earn a wage. But the class difference is not necessarily heredity, since individuals can change classes. Moreover, it is a relatively abstract class structure, because it does not necessarily divide the members of a spiritual animal into different classes. Particular individuals can occupy both roles as long as capitalists can hire workers and the necessary relationship of domination and submission exists.

Capitalism is a contained form of reproductive causation in which the “reproducing organisms” that evolve are processes of production, because they have both kinds of structural effects, reproduction and non-reproductive work.

Production processes are capable of reproducing themselves, because when the sale of the commodities returns more money than was invested in them, capitalists will invest not only in another round of production, but also in expanded production processes. That is, they reproduce in space as well as in time.

Processes of production also do non-reproductive work, like reproducing organisms, namely, producing commodities. Such structural effects can control the conditions that affect the reproduction of the process, because they can be sold on the market for a profit.

What makes capitalism a form of evolution by reproductive causation is the competition among capitalists for a profit on their investments. The reproduction of production processes by the reinvestment of profits expands their population, and since the market for any commodity is finite, some production processes will eventually be unable to make a profit and their reproductive cycles will come to an end. Thus, a natural selection is imposed by their own reproduction, just as in biological evolution, except that it occurs among production processes within a spiritual animal. That is how reproductive cycles of production processes add up over time in the “space” of a spiritual animal.

It is not just chance, however, which processes of production succeed in reproducing, because those capitalists who can produce the same commodities more efficiently (or more useful commodities just as efficiently) will be able to make a profit from selling their commodities and thereby reproduce their process of reproduction, while other, less efficient production processes will not. This form of natural selection will be called “capitalist selection.” Capitalist selection is made by success in reproducing, as in biological evolution, but it is made for returning a profit and, thus, for producing commodities more efficiently. Since capitalism constitutes the ontological cause for gradual evolution, the simpler reproductive global regularities, it is ontologically necessary that there will be change of production processes in the direction of natural perfection for both the processes of production and at the ecological level.

Capitalist selection means that there will be a gradual change in the direction of maximum holistic power for production processes of their kind. Their greater power is holistic, because when all possible efficiencies are made, all the conditions affecting their reproduction that can be controlled come to be controlled.

At the ecological level, the ecological niches to which production processes adapt are the various kinds of commodities that people are willing to buy (because they are useful in some way), and the “free energy” being tapped is the money people are willing to spend. At the ecological level, therefore, there are many different industries, and since in each of them, capitalists compete for profits, overall production in the spiritual animal changes in the direction of a maximum holistic power at the ecological level that parallels biological evolution. Production extracts as much money from consumers as possible while at the same time using the fewest and simplest factors to produce the commodities they buy.

There is, however, a new wrinkle in the case capitalist economic evolution, because natural science supplies new means for producing useful objects, and these technological changes not only make production of the same commodities more efficient, but also make it possible to produce other commodities (that is, other kinds of useful objects that people will buy). But it is a two-way street, because the evolution of capitalist production also develops the technology that natural science needs to progress in the discovery of the efficient causes at work in nature. Thus, there is an interaction between capitalism and natural science that propels the evolution of both, one by capitalist selection and the other by rational selection.

Like any stage of evolution, therefore, kinds of production processes start off simple, uniform and barely able to make a profit (controlling the conditions that affect their reproduction), but as a result of reproductive causation by capitalist selection, they become increasingly complex, diverse and powerful at making a profit. But considering how the evolution of technology combines with cultural evolution to propel the evolution of natural science, the gradual change of production processes in the direction of maximum holistic power is chasing a goal that is continually receding because technological advances are not merely increasing the efficiency in the production of the same commodities, but changing the commodities that must be produced to make a profit. It is as if the ecological niches were changing as the organisms adapt to them, though it can also be seen as capitalist production evolving maximum holistic power to satisfy the wants of the members of the spiritual animal.

Civilization must evolve before capitalism can begin, because competition among capitalists in the production of commodities requires a large market. And a class structure must already exist to put individuals in a social situations in which it is possible to try out the capitalist class structure as a random variation. That does not mean, however, that capitalism inevitably evolves from civilization. The institutions required for capitalism include not only a market for exchanging goods, but also a market for purchasing and selling labor power, and since such exchanges must be made with a great efficiency and reliability, the culture of the spiritual animal must include rather demanding rules about contracts. Moreover, the institution of property must not be so committed to feudal forms of land ownership for individuals to accumulate large quantities of capital. Such conditions are provided as we shall see, in philosophical spiritual animals. That is very likely the only situation in which capitalism can evolve for the first time. It is, in any case, the only kind of spiritual animal in which capitalism will have the evolution of natural science to interact with.

It seems likely, therefore, that history, the penultimate phase of overall evolution, is the result of an interaction between stages of social evolution and stages of cultural evolution.

Culture generates the institutions (mainly property) on which a civilized social structure depends, and civilization (class structure) provides the conditions necessary for epistemological philosophical culture to evolve.

Epistemological philosophical culture apparently provides the conditions necessary for capitalism to evolve in civilized society.

And capitalism is required, as we shall see, to provide the conditions for ontological philosophical culture to evolve from epistemological philosophical culture, because without the interaction between the capitalist evolution of production and the cultural evolution of natural science, natural science would not advance far enough for ontological philosophy to be convincing.

Pre-Socratic philosophy. Let us, therefore, set the stage for the first step in this sequence and explain how epistemological philosophy evolved in rational level culture. Its way is prepared, as I have suggested, by a primitive form of ontological philosophy, because the most obvious way to construct an arguments with a higher level of forensic organization than those rational level culture is on the basis of naturalistic understanding. From the historical record, we know that it occurred in ancient Greece. The Pre-Socratic philosophers tried out a kind of philosophical argument that was promising enough, despite being doomed by the lack of natural science, to become the model for epistemological philosophy.

Conditions were especially favorable in ancient Greece. Not only did the ancient Greeks have writing, a class structure to support a leisure class, and a love of argument, but there was a number of more or less independent spiritual animals with the same culture, located in different city-states. Since they traded by sailing across the Aegean Sea, they could exchange arguments, but their physical separation from one another made it hard for any one city state to completely dominate all the others, as happened in other early civilizations, such as Egypt and Babylonia. Since there was no centralized government that could increase its power by suppressing the exchange of arguments, it was possible for culture to evolve freely. And as it happened, the ancient Greeks had great respect for argument and sound rational judgment.

The autonomy of city-states in ancient Greece indicates that they were independent spiritual animals. But there were periods in which these spiritual animals were united more like a single spiritual animal, for example, in the Persian wars early in the fifth century. On the other hand, there were also periods in which they were so independent that they were at war with one another, as in the Peloponnesian war in the late fifth century. This raises a general issue about the boundaries of spiritual animals.

The boundaries of spiritual animals. The nomadic band of language using animals is the original model for spiritual animals, but even before agriculture, the extent to a single spiritual animal was unclear, because nomadic bands were related in tribes and tribes could act as a whole, for example, in wars with other tribes. The capacity of spiritual animals to merge and divide makes their boundaries inherently less permanent than other organisms. But in general, the reality of the social level animal is manifest in the capacity of the members to act as a whole to control all the conditions affecting social level reproduction, and the extent of its population depends on how broadly the behavior of rational subjects are coordinated in generating social level behavior. Though this unity is most obvious in its original form, the nomadic band, it can still be seen in the nation state, where the institution of government makes territorial boundaries clear, for they are units that are responsible for everything done as a whole. Even there, however, boundaries shift, and in the contemporary period, nation states may be in the process of being obliterated entirely as spiritual animals slowly merge into a single, planet-wide spiritual animal.

The capacity of spiritual animals to merge and separate does not, however, show that they are not social level animals. What the shifting boundaries of spiritual animals show is that they have a spiritual nature, for their spiritual nature makes it as easy for them to merge with one another as to divide and reproduce. Thus, it may make sense to think of groups within contemporary complex societies as spiritual animals, when they normally act as a whole independently of other groups over long periods of time. Indeed, we might even think of spiritual animals as being quite local and transient, for that is what is suggested by the notion of individuals having a spiritual body, as well as a physical body, to pursue their goals. (That is, members of spiritual animals can be said to have spiritual bodies, because they can enlist friends and occupants of social roles to cooperate in the attainment of their individual goals, as a local and limited way of generating social level behavior.)

But the essential nature of spiritual animals can be seen most clearly from their place in the stages of evolution, and that suggests the capacity of spiritual animals to control all the conditions that affect their reproduction is as important as their capacity to act as a whole. The power that is maximized by reproductive causation is holistic, and so the natural perfection that determines what is good for them has to do with the unit that has the final authority to act in every way for the members, that is, the government. It is in the state, therefore, that the spiritual animal exists most completely.

Pre-Socratic philosophy began about 600BC when Thales argued that everything is water. As we should expect, it began with a dissatisfaction about religious explanations. The Pre-Socratic philosophers did not want an explanation by the motives or actions of gods, spirits, or any other unseen beings with a nature like their own. Instead, they were looking for another kind of cause, the simplest assumption needed to explain nature. They called it the archê, which is variously translated as “first principle”, “beginning”, “origin of things”, or simply “first”.

At the beginning, the ontological way of providing an archê was at least as obvious as the epistemological. It is clear that what most of the Pre-Socratics were seeking as an archê was the substance that would explain everything in the world, and everything about the natural world, including change and diversity. They tried out various conceptions of material substance and various ways in which such an archê could explain nature.

Thales’ theory that the basic substance is water gave rises to other views during the first phase involving the Ionian pre-Socratics. Anaximander held that the basic substance was the apeiron, or the “unlimited, suggesting that substance is substratum in which opposite properties compete to occupy, as if it were a disputed territory. Anaximines argued that it is air, because then condensation and rarification could explain the change in properties and the diversity of kinds of substances.

Their attempts to explain the natural world by material substance makes it clear that the Ionians were giving an ontological explanation of the world, but another strain of Pre-Socratic philosophy explored the epistemological alternative, at least, in a primitive way. The Pythagorean philosophers responded to Ionian philosophy by trying to explain the natural world as constituted, not by material substances, but by numbers. Numbers are the concepts established in imagination with the evolution of the behavioral schemata for counting (because the same covert behavior of assigning one word in the unchanging sequence of words for each object would work regardless of the kinds of objects being counted). Numbers as abstract entities are known through reflective understanding, not naturalistic understanding, because they are units in the linguistic structure of the spiritual animal under its cultural aspect, and the peculiar nature of the knowledge we can have about numbers was part of the mystical ceremonies on which Pythagoreans based a religion. In any case, they took an object known by reflective understanding to be the first cause underlying the world, though numbers were associated with geometrical structures as a way of showing how they could explain natural phenomena.

In a second phase of pre-Socratic philosophy, problems about the nature of ontological explanation emerged in the form of a dilemma acted out in the choice between Parmenides and Heraclitus.

Parmenides argued that, if the world is to be explained by a single substance, change must be an illusion. As he put it, “What is, must be, and what is not, must not be.” This is a way of describing the temporal nature of substance, that is, as a self-subsistent entity that can neither come into existence nor go out of existence, but is permanent. That Ionians assumed that the archê is a single substance, and Parmenides was pointing out that, if so, there can be no change, because there is nothing in the world to come into existence or to go out of existence over time. Thus, he insisted that what exists is the One, or Being, and he conceived of its as an unchanging sphere of matter, for he realized that for any parts of it to be separated from any other parts, there would have to be something else that exists between them.

What seems to come into existence and go out of existence over time are properties, and Heraclitus explored the other horn of this dilemma. He also accepted the Ionian assumption that what explains the world is a single, first principle, but instead of taking it to be substance, Heraclitus took it to be change itself, that is, the coming and going of properties from existence. He called it “fire,” but his paradoxical pronouncements about the archê make it clear that fire was just a symbol for the changing properties that we perceive in nature. He said, for example, that one could, and could not, step in the same river twice. One can step in the same river twice, because things do seem to be permanent. Change is regular, being governed by Logos (or natural laws of some kind). At the same time, one cannot step in the same river twice, because the water constantly changes as it flows. The river is probably a metaphor for objects of any kind. Permanence is an illusion, because objects that seem to be unchanging are actually just a flow of properties, each existing only at the moment. That is, Heraclitus would insist that you cannot even stand on the same river bank twice.

An inherent defect in the very nature of the Ionian explanation was surfaced by the dilemma that Parmenides and Heraclitus posed. The Ionians explicitly wanted to explain the change and diversity in the natural world by an archê, a single, first principle. But if that archê is substance, then nothing exists to explain the change and diversity. And if change itself is the archê, then there is no substance. (There is nothing but transient, changing properties.)

A third phase of pre-Socratic philosophy discovered what was required for ontology to be explanatory. The solution to the dilemma was to postulate more than one kind of basic substance and explain change and diversity by different combinations of those substances, though there was a disagreement about how many basic substances there are.

Empedocles postulated four kinds of substances, earth, air, fire and water, and since these “element” were assumed to have different kinds of properties, it seemed that the change observed in objects could be explained by their mixture and separation. And different kinds of object could be explained by different proportions of the basic elements constituting them. Though Empedocles just assumed that his elements were able to move in the ways required to mix and separate, he explained why they mix and separate in the regular ways they do by postulating two forces, love and strife. Love drew different kinds of elements to one another, mixing them, and strife repelled them from one another, separating them.

Anaxagoras insisted that there are infinitely many different kinds of basic substances, or what he called “seeds,” and infinitely many seeds combined in each observable object. He explained change and diversity in the same way as Empedocles, and the difficulty of explaining the enormous range of the diversity and different kinds of change without only four substances that led Anaxagoras to increase the number of basic substances so profligately. In any case, he recognized that this mode of explanation required him to postulate a force to explain why change takes place the way it does, but instead of love and strife, he postulated mind (nous).

The need to postulate infinitely many different basic substances to explain what is perceived in nature all but renounced the Ionian attempt to find an archê, a first principle, but other problems with this kind of explanation were also pointed out by Zeno, a student of Parmenides. One reason for holding that the parts of ordinary observable objects are infinite is that they are always divisible. But Zeno pointed out that an object of finite size cannot be made up of parts that are infinitely small parts (like Anaxagoras’ seeds), no matter how many such parts there are. And if the parts have finite sizes, there cannot be infinitely many of them. Furthermore, there were problems with the basic mechanism of change presupposed by both Empedocles and Anaxagoras, because they must assume that the basic substances can move in order to explain how they mix and separate. The basic problem is that motion must be made up of momentary parts, but if there is no motion at each moment, there is a similar problem about how all the moments can constitute motion.

In the final phase of pre-Socratic philosophy, the attempt to solve these problems led to the discovery of the best ontological explanation of the natural world. All the change and diversity in the world could be explained much more simply by postulating just two kinds of opposite elements, or substances.

Leucippus and, his student, Democritus argued that the natural world is made up of atoms and the void. The atoms were bits of matter with infinitely many different sizes and shapes, and though scholarship is divided on this point, they could have believed that the void is an opposite kind of substance that contained them. They insisted that both elements must be postulated in order to explain motion, because without the void, there would be no room for atoms to move. And if atoms can move, then everything that happens can be explained as simply the result of how their geometrical structures interact with one another, for example, like a hook and an eye to bind with one another (that is, structural causation).

(Many scholars hold that the ancient atomists did not believe that the void was supposed to be a substance that exists everywhere and coincides with the atoms where they are located. Instead, they insist, the void was assumed to exist only at those locations where atoms do not exist. That is, however, to treat the void as a very subtle kind of material substance that can flow around atoms as they move. That makes atomism more like what is later called “plenum theories,” which deny that there is any void. Furthermore, that interpretation makes it hard to see how the ancient atomists could think that the void explains how motion (and, therefore, change) is possible.

Atomism gave rise to another problem, however, which made it incredible. It replaced material substances whose essential natures were defined by qualitative properties, such as hot and cold, dry and wet, and various colors, with material substances whose essential natures were defined by their geometrical structures. That was attractive, because it was possible to explain change as determined necessarily by the motion and interaction of atoms, avoiding the need to postulate other forces, such as love and strife. But it required some explanation to be given of the qualitative properties that objects appear to have, and there was no plausible alternative to recognizing that they depend on the subject, or as Democritus put it, they are “by convention.” Thus, atomists gave up naïve (or direct) realism about perception in favor of critical realism. But that merely underlined the need for an explanation of the nature of the subjects who know about the world. Though Democritus insisted that the motion and interaction of atoms in the void explains the capacity for reason, by which subjects can recognize the necessity about what happens in a world, but his way of explaining reason was to hold that there are special, spherical atoms in the brain. Spherical atoms are as incapable of explaining these appearances as they are unable to explain the capacity to understand necessity in the natural world.

Even though Pre-Socratic philosophy discovered the nature of substance, recognized how substance could explain the world, and even discovered that spatiomaterialism is the best ontological-cause explanation of the world, it did not establish ontology as a way of doing philosophy. It did provide a model for the attempt to construct arguments with a higher level of forensic organization than rational level culture, for it not only rejected religious explanations, but also found a kind of explanation that could promise, at least, to explain everything in the world in the same way. But such a complete explanation must also explain the existence and nature of beings who are able to understand the first level arguments of rational culture. Though Democritus’ theory about spherical atoms can be seen as pointing to neurological mechanism, it is a far cry from explaining how nothing but the motion and interaction of atoms in the void is able to understand the motion and interaction of atoms in the void. And though Democritus gave a plausible explanation of goodness on the assumption that pleasure is the ultimate aim of all behavior, that did not explain goodness in the way Socrates wanted, and in any case, talk about pleasure merely focused attention of his lack of an adequate explanation of the qualitative aspect of experience (that is, consciousness). But ontological philosophy could not do better than Democritus until the evolution of natural science, when the discovery of the details about how “atoms” move and interact at the micro level made it possible to trace out the course of evolution and discover how the brain works.

The career of epistemological philosophy. Pre-Socratic philosophy was a radical random variation on the arguments of rational level culture, and it may also have been tried out in other civilizations. But only in Western civilization did it give rise to epistemological philosophy and put the linguistic structures generating social institutions on the philosophical level of neurological organization.

Ancient and medieval epistemological philosophy. Epistemological philosophy began when Plato discovered a convincing way of constructing an argument that would explain the validity of all first level arguments based on perception and desire. It was also an explanation of everything, but it was not based on a theory about change and diversity, that is, about efficient causes. Instead, it was a theory about the nature of reason based only reflective understanding, or the capacity of subjects to use rational imagination to explain rational causation. It did entail an explanation of the nature of the substances constituting the world, but that was an afterthought, for its approach to philosophy was epistemological. The theories about the nature of reason and the nature of consciousness that we have derived from our ontological foundation fit together as a way of understanding the basic structure of epistemological arguments. We need only consider what rational subjects had to work with, when they turned to reflective understanding for a theory about how we know about the world, because there are only certain ways that those elements can be used to explain the validity of the reasons used in the ordinary arguments of rational level culture.

What represents the current scene to the subject are the telesensory images that are currently being used (in conjunction with input from the current bodily condition) to construct a local image, and together with the representation of the body itself, that is the subject’s perception of the world. But the local image (and the body image to which it is related) generated from current sensory input are embedded within a faculty of rational imagination, and thus, rational subjects are able to see actual states against the background of what is possible by efficient causation by using covert behavior to call up all sort of images in relation to them. Consider the aspects of the world that are represented in rational imagination.

Spatial imagination makes it possible to call up sequences of images representing the effects of the locomotion (or motion) in relation to other objects within the local scene and to call up sequences of local images (that have been recorded in memory as a map of one’s territory) representing locomotion beyond the local scene. Or spatial imagination can be used more generally to think about the effects locomotion and turning (or motion and change of direction) within the local scene, in relation to a purely imaginary local scene, or in the abstract (because the same behavioral schemata are used relative to different local images).

Structural imagination makes it possible to call up sequences of telesensory images, or object images, representing the effects of manipulating objects in the local scene, such as rotating and twisting them, and it too can be used abstractly to think about the geometrical structures of objects in space.

Naturalistic imagination, which comes with the ability to use natural sentences, makes it possible to call up sequences of images, or naturalistic images, representing the states of affairs that make natural sentences true, so that together with (particular and general) beliefs about regularities (which are either built into the structure of imagination or acquired from experience), rational imagination can represent their effects in the natural world.

Rational imagination, which comes with the ability to use psychological sentences, makes it possible to call up sequences of images as psychological predicates (or psychological images) and to predicate them of objects in space that are subjects, and this ability to think about psychological states is the ability to understand how they are causes or effects of other psychological states, including their role as reasons (or causes that are represented as causes as part of the process of causing beliefs or behavior).

Perception and rational imagination both have an appearance to the subject. These images are certain configurations of neurons firing in various 2-D arrays of neurons that are connected by projections between the thalamus and neocortex (or between regions of neocortex), and their firings are all synchronized by the thalamus insofar as they have to do with the same objects. That is, the brain processes the information contained as patterns of firing in 2-D arrays of neurons, and thus, what happens in the brain is a highly structured in both space and time. But what is more, the joint firings of those neurons is like a complex antenna that generates a steam of photons, and the intrinsic natures of the photons being given off by the active brain are phenomenal properties which make the rational subject conscious.

Perception and rational imagination have different appearances, because the images they involve are caused in basically different ways. Perceptual images come from sensory input (and involve projections from the sensory organs through the thalamus to the neocortex), whereas images of rational imagination come from covert behavior operating on memory (and involve only regions of neocortex beyond those registering sensory input). This makes these two kinds of images appear quite different from the point of view of the subject reflecting on them. But in both cases, objects seem to be present to the subject, in one case, as objects of perception, and in the other case, as objects of reflection.

The only plausible way to construct an epistemological argument is to assume that the appearances of these objects in consciousness involve an intuition of objects that exist independently of the subject, for there is nothing else to reflect on, except the feelings or emotions associated with desires (that is, the goal selection system).

The images of perception naturally appear to be objects in space, because the local image represents the objects as having locations in space relative to one’s body. Though the telesensory images are certain groups of neurons firing in 2-D arrays that are located in certain regions of the thalamus and neocortex, they seem to be located in space, because as we have seen, they are combined with other telesensory and somatosensory images as part of a local image, and with spatial imagination, the subject is able to think about the effects of motion relative to them by calling up sequences of images in imagination. The sensory images of objects are seen, therefore, against the background of what is possible by motion, and since that is how the subject understands the structure of space, the objects appear to be located in space. And it is a qualitatively rich appearance, because in conscious subjects, what is happening throughout the brain is registered in the structures of the photons being generated by it.

Naïve (or direct) realism about perception, as this way of interpreting perceptual images is called, is the natural attitude, because there is ordinarily no reason to recognize the difference between perceptual representations in the brain and the objects in space they represent outside the brain. The overt behavior of one’s body actually changes the perceptual images in just the ways one expects. Thus, it is natural to think of perception as an immediate intuition of objects in space, including one’s own body, as if the objects themselves were immediately present to the subject.

Objects of reflection, such as the object images representing objects of various kinds that evolve as the meanings of some general terms, also have an appearance, albeit one that is less vivid, detailed, and persistent, because they are images in rational imagination. They might also ordinarily be taken as objects present to mind by way of intuition, but they do not act like objects in space. They may be imagined as located in space relative to objects that are perceived, but unlike the latter, what changes them is not the overt behavior of one’s body, but the covert behavior by which one calls up images from memory. Imagined object are easier to handle. Not only are they not constrained like objects in space, but neither do they appear to be in time. Though object images involve sequences of images in imagination, such sequences are simply the meanings of the general terms. The meaning of “cube” or “tree,” for example, may include a sequence of images representing the effects of rotating it or moving around to see it from the other side, but that is understood to be just a way of thinking about the nature of the cube or the nature of the tree. The object itself is unchanging and, thus, not in time. The natural attitude is, therefore, to assume that the objects of reflection are in the mind, that is, merely subjective.

However, since objects of reflection are appearances quite on a par with objects of perception, it is possible to think of both as intuitions of objects that somehow exist independently of the subject. Thus, just as the tree that is perceived is seen a located outside the subject in space, so the image of reflection that is the meaning of “tree” can be seen as located outside the body in some other way. The connection between these independently existing objects affords an explanation of the objects of perception, for it is possible that the objects of reflection are also somehow what causes the objects of perception to have the natures they seem to have. That is what Plato did by positing the existence of Forms in the realm of Being beyond the visible objects in the realm of Becoming.

This theory about the nature of reason overcomes, therefore, the dichotomy between the objects of naturalistic and reflective understanding. It uses it as an explanation of what exists in the world. But that was not, of course, the only cause of Plato’s metaphysics. Plato was looking for a metaphysics that would also explain the nature of goodness, that is, a way of overcoming the dichotomy between the true and the good and the dichotomy between the good of satisfying animal desire and a higher good (self interest and spiritual interest).

The dichotomies that philosophy must overcome include not only the difference between the science of nature and the science of subjects, but also the difference between the true and the good. In addition to cognizing the true, reason has the power to guide behavior, and thus, it also seeks to know what is good. Practical arguments became the focus of attention after the Persian wars, when Athens was the dominant city-state and the exchange of arguments was supported by the hiring of teachers, called sophists, to train the sons of the wealthy to be leaders in the promising, new age of independence.

The sophists were itinerants, traveling from one city state to another, gathering knowledge as well as teaching, and this cosmopolitan experience led them to conclude that the standards of justice and other virtues are conventional, that is, true merely because they are believed to be true in a society. In this context, Socrates was on the side of traditional religion, holding that the good is objective, or something about the world that could be known like natural science. But instead of the dogmatism of traditional religion, Socrates insisted that knowledge of the good must be a kind of knowledge that makes the knower virtuous, so that a rational being does the good because it is good and he understands why it is good. That is the meaning of the Socratic principle, that knowledge is virtue. There must be an understanding of the nature of goodness that is so deep that it explains to rational beings why they ought to pursue it. The Socratic principle posed very sharply the problem that philosophy must solve in explaining the relationship of the good and the true. For how can any mere fact about the world show that something is good in a way that gives rational beings a sufficient motive to do it?

Socrates was implicitly asking for a philosophical argument, because he wanted to know what makes all good thing good, which would explain why ordinary arguments about what is good are valid (when they are). And it was his attempt to answer Socrates’ challenge that led Plato to discover the epistemological approach to explaining all the arguments of rational culture. Recognizing that it is possible to think of certain objects of reflection as objects existing independently of the subject in much the same way as objects of perception, as explained above, Plato argued that what makes visible things good is that they are participating or imitating Forms in the realm of Being. This meant that he had to hold that the Forms in the realm of Being are themselves good, and so he argued that all the other Forms follow from the Form of the Good. This was not very satisfying explanation of the nature of goodness, but the transcendence of the realm of Being, or its existence outside space and time, made it possible to think that Being could somehow be the source of goodness. Thus, his metaphysics of Being and Becoming could be used to justify arguments about what is good in a fundamentally different way from ordinary arguments of rational culture, and it was the same way in which he could justify arguments about what is true in the natural world. In both cases, it had to do with visible objects imitating the Forms.

That Plato’s goal was to construct a new kind of argument that would explain the validity of the arguments of rational culture is also evident in his use of this metaphysics to overcome the third dichotomy, between individual and spiritual interest. He argued in The Republic that the state is the individual “writ large.” He showed that the soul of the individual rational subject has three parts: reason, appetites, and a “spirited element” which enabled reason to take control of the body away from the appetites (or what we have found to be the desire to submit to reason). He showed that the functions of these three elements also had to be served in the state by three classes of citizens: rulers, ordinary producers, and an army/police force to enforce the rule of the leaders. He suggested that both are good for the same reason, because of the harmony among the three parts required by their Forms. In both cases, it meant that reason, with the aid of an animal-like power (the spirited element), would prevail over mere animal desire. Thus, Plato defended a view which subordinates the individual to the good of the spiritual animal as a whole in a way that seems almost totalitarian from the contemporary perspective.

The subsequent developments of epistemological philosophy during the ancient and medieval period are a story about attempts to solve problems it caused and how its marriage with Christianity eventually made philosophy the foundation of subsequent Western culture. Only the highlights need be mentioned here, for our goal is merely to sketch the career of epistemological philosophy in order to show how its various forms are variations on the same theme.

As even Plato recognized, the gulf between Being and Becoming is a major problem with his metaphysics. How is it possible for such opposite kinds of entities as unchanging objects of rational intuition and changing objects of perception to be related as parts of the same world? Plato found himself holding (even in the Timaeus, where Becoming is explained as being constituted by the “receptacle,” or space, and “moving images” of the Forms) that they are different substances, and in order to defend his epistemological argument for the independent existence of the Forms, it was necessary to explain how these two substances are related to one another. It was Aristotle who attempted to solve that problem.

Aristotle accepted Plato’s epistemological approach to philosophy and posited objects of rational intuition as fundamentally different from the objects of perception. However, he insisted that they were not different substances, but merely irreducibly different aspects of the same substances: essential forms and matter. This afforded Aristotle a more convincing explanation of the natural world, because he could insist that just as the material aspect of particular substances makes them able to act on one another and, thereby, account for efficient causes, so the formal aspect of particular substances makes them subject to final causation, that is, the tendency of essential forms that are merely potential to become actual, and thereby account for functional explanations. This teleological view of nature enabled Aristotle to account for the regular changes observed in biological organisms, and he extended the same kind of explanation to physics and astronomy.

Teleology gave Aristotle a theory about how the good is related to the true that resembled Plato’s, because he could hold that what is good for any substance is the full actualization of its essential form. The difference is that, having denied the existence of a realm of Being, Aristotle could not hold that the essential forms are explained by the nature of goodness (The Good Itself, as Plato called it). He had to argue that the good is different for different substances (and, thus, that the only reason it is good is that its essential form happens to exist in the world). Aristotle attempted to explain the relationship between individual interest and spiritual interest by holding that rational animals are essentially social (though he did not explain how substances with one essential form could jointly constitute a higher level organism with its own essential form without giving up their essential form as individuals).

The difference between essential forms and matter confronted Aristotle, however, with the same kind of problem that faced Plato, for as he recognized, there had to be an explanation of the relationship between them. This led Aristotle to argue in the Metaphysics that individual substances are basically essential forms and that the material cause is merely their particular existence, or as it came to be called, a mere “principle of individuation.” (In terms of the nature of substance as explained here, Aristotle tried to avoid holding that form and matter are basically different substances by reducing the difference between form and matter to the difference between the essential and the existential aspect of each particular substance.)

Though Aristotle tried to naturalize Plato’s metaphysics by denying the existence of a separate realm of Being, Plato and Aristotle were both realists about forms. Both believed that, in addition to perceptible objects, there are intelligible objects. But since what they were talking about were actually images in the faculty of perception and (certain) images in the faculty of rational imagination, which have a phenomenal appearance to the subject, it is not surprising that there is no adequate explanation of the relationship between them when they are taken to be objects existing independently of the subject, regardless whether it is conceived as a relationship between visible objects and Forms or between matter and essential forms. The inability of realists about forms to formulate a metaphysics that could explain adequately how they are parts of the same world as material objects in space led to doubts about their existence, and thus, realism gave rise to anti-realism. Anti-realism was acted out mainly during the Roman era.

Philosophy continued to be discussed by educated people in the Roman empire, but the two most popular philosophical systems abandoned realism about forms in favor of materialism. The Epicureans believed in atoms and the void, and the Stoics believed that the world is constituted by two kinds of matter, ultimately, active matter and passive matter. (Active matter replaced essential forms as the cause of the order found in nature, for it was supposed to give passive matter into all the proper structures and behavior.)

Neither was much concerned about overcoming the dichotomy between naturalistic and reflective understanding, for both simply took it for granted that rational subjects are part of nature. But they called themselves philosophers, because they were interested in overcoming the dichotomy between the true and the good. They prized Greek philosophy as the model for the higher form of reasoning that would give them wisdom, though the kind of wisdom they sought was practical. Epicureans followed Democritus in defending hedonism, the view that pleasure is the one and only ultimate good and pain the only ultimate evil. They used the determinism of atomism to argue that rational beings cannot help but pursue pleasure and avoid pain. Stoics held that the good life is to suppress all desire for anything different from what happens. The believed that everything happens for the best, because active matter pushed passive matter around in a way that makes the world as a whole a perfect being.

Even as an attempt to overcome the dichotomy between the true and the good, however, Epicureanism and Stoicism were less philosophical arguments than the attempt to have an alternative to traditional religions in thinking about how to live. Neither even attempted to explain how the true makes the good good except to insist that the highest wisdom of philosophy is to make peace with natural necessity. Epicureans never tried to explain why there ought to be rational beings in the world who must pursue pleasure, and the Stoics never explained what it is that makes the world shaped by active matter perfect.

Medieval epistemological philosophy. Toward the end of the Roman era, there was a revival of interest in Greek philosophy as a way of overcoming the dichotomy between naturalistic and reflective understanding. (Plotinus formulated a variation on Plato’s metaphysics that tried to overcome the dualism of Being and Becoming by taking the ultimate source of everything to be the One and explaining the rest of the world as levels of emanations from it.) But Plato’s dualism is what sealed the marriage of Greek philosophy with Christianity, giving Western civilization a uniquely philosophical religion. Later, with the inclusion of Aristotelian philosophy, its rationalism was complete, and the effect on subsequent civilization was profound.

The Judeo-Christian belief in a God who created the natural world combined easily with Plato’s metaphysical dualism of Being and Becoming. Being could be reinterpreted as a supreme rational being, that is, a person. (Plotinus had already portrayed the Forms as aspects of a self-thinking being in the first emanation from the One.) Since God created the natural world, it was possible to take God to be the objective source of goodness that Socrates and Plato were seeking. Thus, Plato’s way of overcoming the dichotomy between reason and nature was resurrected.

But Augustine was the matchmaker, and his belief that it was simply the will of God that made the good good undercut the rationalistic intent of Socrates and Plato by implying that it is arbitrary. However, with the rediscovery of Aristotle in the Middle Ages, that defect was corrected by Aquinas. He argued that what God knows, rather than his will, explains why the good is good. That is, God’s self-understanding includes an explanation of the nature of goodness that reveals why the good ought to exist. And since that knowledge of the nature of goodness is what guided God to create a world like ours, His will was free. God turns out to have the wisdom that Socrates was seeking.

The upshot is that the belief in wisdom as a higher form of argument that can give us a seamless and complete understanding of the true, the good, and the beautiful became, though its adoption by Christianity, a basic principle in the evolution of the arguments about social roles that generated the institutions of Western civilization as the Middle Ages gave way to the Renaissance and the modern era began. The belief that social roles had to be justified by basic principles about the nature of morality and justice that could be known by reason, and the belief that each rational subject has a free will which makes him ultimately responsible for his behavior (and the eternal fate of their souls) led to institutions that recognized the autonomy of individuals and the sanctity of contracts. That gave the edge to institutions of private property and market exchange that would make it possible for capitalism to evolve, helping to pave the way for ontological philosophy.

Modern epistemological philosophy. In the modern era, epistemological philosophy took a fundamentally different form, though its theories of reason were based on the same two elements: perceptual and rational intuition. The difference was caused by modern science, another offspring of ancient and medieval epistemological philosophy which forced the recognition that the ancient atomists had been right to reject naïve realism about perception.

By the renaissance, mathematical arguments had evolved far enough for it to be recognized that there are quantitatively precise regularities about what happens in the physical world and that they can be represented mathematically. Ever since Plato (or even Pythagoras), mathematical knowledge had been the model for the deeper kind of knowledge about the world that epistemological philosophy was supposed to make possible, and mathematical knowledge evolved as philosophers become mathematicians exchanged mathematical arguments.

On the other hand, the belief that the natural world had been created by God, a rational being, made it plausible to assume that nature had been designed using mathematical concepts. Mathematics was the “language of nature,” as Galileo put it, and thus, it was plausible to assume that the use of mathematics in physics would enable rational subjects to see into the mind of God.

The first advances in physics were all discoveries of quantitative laws of nature, including Kepler’s laws, Galileo’s laws, and before long, Newton’s laws. Even Copernicus had defended his revolutionary view of the universe as a mere mathematical possibility. Mathematics provided the tool that eventually pried open the lid that had long kept reason from understanding micro level processes, leading eventually to chemistry, biology and neurophysiology. Since it was a gift of the previous era of philosophical culture, it is ironic that its first main effect was to replace naïve (or direct) realism about perception with critical (or representative) realism.

The belief that the physical world is made up of substances whose ways of moving and interacting can be described by quantitatively precise laws of nature was recognized as materialism, but it was a form of materialism that had to deny that matter has any of the qualitative properties it seems to have. Those qualitative properties had to be explained as effects on the subject that are caused by the objects through chains of causation that could be explained by laws of nature, which is basically the conclusion to which ancient atomists, like Democritus, had been driven as the conclusion of Pre-Socratic philosophy two thousand years earlier, and for much the same reason. (The belief that shape and size were the only essential properties of atoms was also a quantitative view of matter.) Modern scientists understood that perception of objects in space, for example, by vision, had to be caused in some way by something that travels from the object across space over time to the subject. And since anatomy had made it clear by then that the brain was responsible for receiving sensory input and guiding behavior, there was, within the body, a second leg of the chain of causes and effects that were responsible for how it appears to the subject (implying thereby that the body also lacked the qualitative properties that seemed to be located in it, such as the feel of hot and cold).

This view had a profound significance for anyone who would attempt to take the epistemological approach to showing how the validity of all the arguments of rational culture can be shown by a theory about the nature of reason that was based on reflective understanding. Ever since Plato, epistemological philosophy had been founded on naïve realism, the assumption that the perceptual appearance of the world is an intuition of objects that exist independently of the subject (or else are properties of the same kind as those that exist independently, as Aristotle held). But in the modern period, it was recognized that the appearances of object in perception have a basically different nature from what actually exists independently of the subject. It is called “critical realism,” because it reject the naïve view, or “representative realism,” in contrast to the :direct realism” of ancient and medieval philosophy. Since the perceptual appearances must someone be part of the subject, the subject himself must be a basically different kind of entity from the objects in space. It was called the “mind,” and the appearances of objects in perception were called “ideas of perception.”

Since the implications of this line of reasoning are not well recognized, it is worth emphasizing something about them that confirms our explanation of how the brain works. It is not only the qualitative properties of the objects of perception that are in the mind, but also the appearance that they have locations in space. That is, ideas of perception include the perception of space itself, not just objects in it. Consider, for example, the distance between your face and what you are reading right now. That is a part of space that seems to be as immediately present as the material object on which these marks are inscribed. That is, of course, what we would expect, since the qualitative properties, or sensory qualia, are parts of the telesensory images that are combined along with input about the condition of the body in constructing a local image to represent the local scene. The perception of the distance between your face and the material object embodying the written words is part of the understanding one has of space because of how one can imagine it changing as a result of certain ways of behaving, such as moving your head, turning the object around or moving your body around in the local scene, which is itself seen as just part of an entire world of objects in space. The upshot of this is that what is contained “in mind” is not just sensory qualia, but also a phenomenal space in which all those qualia are located. What one naively takes to be the whole natural word, in other words, is contained in the mind, and what exists independently of it has an entirely different nature, even if it is also assumed to be made up of objects in space. The physical world is made up of material objects in real space.

The modern philosopher who took up the tradition of philosophy and applied it in the modern era was Descartes, and the form of his epistemological argument can also be derived from this ontological explanation of the nature of reason and consciousness. With only perception and rational intuition to use, Descartes used the latter to argue for the existence of the objects represented by the former.

Descartes recognized that the ideas of perception are located in the mind, distinct from objects existing independently as an external world. (That was the point of his doubts about perception based on its similarity to dreaming and the possibility of the ideas being supplied by an evil demon.) For him, therefore, the way to explain the validity of the first level arguments about the natural world by which science was discovering the laws of nature was to show that a world of the kind discovered by empirical science actually exists. That is how he would overcome the dichotomy between naturalistic and reflective understanding. But since his higher level of forensic organization was based on reflective understanding, the only other resources that Descartes could use as a deeper “cause” were other objects of reflection. The ideas of memory and imagination were of little use, since they obviously came from ideas of perception. But there were other ideas, which he called “clear and distinct ideas,” which are certain principles that derive from the structure of the faculty of rational imagination. They differed from perceptual ideas in the same way that Plato’s Forms differed from visible objects, and the prime examples of such ideas were, once again, those of mathematics. But since Descartes was a critical realist, he recognized that clear and distinct ideas are as much part of the mind and the ideas of perception. Plato’s rational intuition of independently existing Forms had become a rational intuition of necessary truths. Thus, in order for this theory of reason to provide a deeper cause explaining the validity of the first level arguments of natural science, he had to argue that clear and distinct ideas could prove that a world of extension exists outside the mind.

His famous argument started with the Cogito, “I think, therefore I am,” his first clear and distinct idea, and proceeded to use other clear and distinct ideas to argue for the existence of a God. God’s perfection precluded His deceiving the finite rational beings He had created, and thus, Descartes concluded that there is a world existing external to mind with the essential nature that rational beings can grasp clearly and distinctly through geometrical reasoning. Thus his theory about the nature of reason explained the validity of the arguments of both reflective and naturalistic understanding, and the proof of the existence of God allowed him to adopt a traditional theological explanation of the nature of goodness.

Descartes’ new way of doing epistemological philosophy was a form of realism, because it took the ideas that are immediately present to mind as its foundation and it tried to prove the existence and nature of a world beyond them. But Descartes’ argument for the existence of the external world was not convincing in the end, and no one has been able to formulate an argument that does what he wanted. Nevertheless, Descartes set the agenda for all of modern philosophy. It would be a battle between realists and anti-realists about the external world. The main obstacle to a proof of the existence of an external world was the fundamentally different natures of mind and body. As Descartes pointed out, body is extended and divisible, whereas mind has a unity that does not admit of such division. That was his argument for holding that God had created them as different substances.

The unity of mind, as we have recognized, is how all the sensory qualia that seem to be located in different places all have an appearance at once to the same subject to which other ideas are also appearing. Consciousness does have a unity that truly does not admit of division like a material object in space.

It may be worth noticing, by the way, that ontological philosophy provides the kind of argument for the existence of the external world that Descartes was seeking. He wanted a clear and distinct idea that would prove the existence and nature of the world external to mind from the point of view of the rational subject, and that is what is provided by this explanation of the wholeness of the world. On the assumption that nothing exists but space and matter (of kinds that explain the truth of the basic laws of physics), not only does it derive reproductive global regularities that explain the essential nature of rational subjects and their place in the world, but it also explains the nature of their consciousness as the intrinsic natures of bits of matter continually given off by active brains. Together, as we have seen, they explains the clear and distinct ideas that Descartes takes to be indubitable. But this explanation is itself a clear and distinct idea in Descartes’ sense. It is distinct in Descartes’ sense (that is, separate from and independent of any idea that is not before the mind), because it is an idea of the whole world, which is everything that exists. And it is clear in Descartes’ sense (that is, with nothing obscure or vague about any of the parts of the idea that is before the mind), because it is an explanation of the entire world and everything in it by the basic substances that constitute its existence. If the rational subject would just look in the right direction, therefore, he would have a clear and distinct idea that entails not only his own existence as a conscious mind, but also the existence and nature of a world that exists independently of mind.

Mind-body dualism was nevertheless an intractable problem in modern philosophy, because it is a form of epistemological philosophy which attempts to explain the validity of ordinary, first level arguments by a theory about the nature of reason that is based on what can be known about reason by reflective understanding. Reflective understanding makes reason seem to be a form of intuition, because all the ideas in the mind seem to be objects of intuition and clear and distinct ideas are just a special kind. But if the subject knows that he has ideas (and, thus, that he exists) because of how they appear, or he knows that clear and distinct ideas are true because of how they appears, the reasons that determine his beliefs can hardly be efficient causes like those that determine what happens in the natural world. Mind must be a fundamentally different kind of substance from body.

The subsequent history of modern philosophy can be predicted, for it is the attempt to vindicate Descartes’ new way of doing epistemological philosophy by overcoming the problems he encountered — or else arguing that it cannot be done, that is, defending anti-realism. In either case, it has to provide some explanation of the validity, if any, of the arguments of rational level cutlure, not only in the science of subjects, but also in the science of nature. At first, it seemed that there must be a way of defending realism about the external world, since mathematics provides an understanding of its essential nature. But the difference in nature between body and mind was even deeper than the difference between Becoming and Being, the two substances of Plato’s metaphysics. Modern philosophers recognized that both realms to which Plato was referring are in the mind (as the ideas of perception and the clear and distinct ideas of rational intuition), and thus, what they meant by the external world was something whose existence Plato did not even recognize.

Continental rationalists like Spinoza and Leibniz hoped to defend realism about the external world by explaining the relationship between mind and body in a different way from Descartes. Spinoza thought mind and body were two different essential natures (“attributes”) of a single substance that constitutes the existence of the entire world, and Leibniz thought that mind and body were both kinds of minds (“monads”) whose relationships, like the monads making up the rest of the world, were a pre-established harmony that God had built into the world from the beginning. But instead of showing how reason could know the existence of an external world, the implausibility of their metaphysical systems brought the whole approach of rationalism into disrepute.

British empiricists, like Locke, Berkeley and Hume, rejected the attempt to use reason to prove the existence of the external world. But they did not give up the Cartesian project. Locke attempted, instead, to explain the validity of the first level arguments of natural science by showing how they are based on ideas of perception alone. But this merely confirmed that the existence of the external world cannot be known in that way, and Berkeley embraced anti-realism about it. Hume agreed, though he focused his anti-realism on causation, showing that perception provides no reason for believing efficient-cause explanations except the regular conjunction of events of those kinds. Though scientists could not share the philosopher’s skepticism about the natural world, they had to agree with empiricists in rejecting rationalist metaphysics, and empiricist skepticism about causation put a real limit on the ambitions of natural science, encouraging natural science to think of its goal as merely discovering the basic laws of nature.

Kant sought to overcome the obstacle that mind-body dualism posed for epistemological philosophy by insisting that the first level arguments of natural science are really about the phenomenal world, that is, the world constituted in part by the mind, not about what exists independently of it. Though Kant did not deny that something does exist independently of mind, he did deny that such “things in themselves” are in space or time. Space and time were mere forms of intuition in the mind. This transformed Cartesian mind-body dualism, because it was no longer possible even to conceive the nature of what exists besides mind. But it did not eliminate metaphysical dualism, because Kant was still a realist about things in themselves outside the mind. And the acknowledgment of a reality that reason could not grasp meant that epistemological philosophy had to admit explicitly that its way of explaining the validity of all the first level arguments of rational culture did not explain the wholeness of the world, but only the wholeness of reason itself. This discovery was more than some defenders of traditional philosophy could accept.

Hegel sought to overcome the obstacle of recognizing the existence of something whose nature reason cannot grasp by constructing from the elements of Kant’s theory of mind a dialectical theory of reason. Instead of helping to constitute a merely phenomenal natural world, as Kant held, Hegel argued that reason constituted the actual natural world and everything about it. By taking individual rational subjects to be merely moments in its dialectic, Hegel could insist that he had shown how reason is able to know the existence and nature of a world existing independently of each particular mind, thereby defending realism, in a sense, and giving a philosophical explanation of why the first level arguments of rational culture (mere “understanding,” in Hegel’s view) are valid. But such absolute idealism merely exposes the real nature of epistemological philosophy as the attempt to discover the deeper cause of the world that is known to rational culture in the nature of reason, rather than in the nature of the world that exists independently of rational beings.

As far as goodness is concerned, the medieval theological explanation was taken more or less for granted during the modern era — until Hume tried to explain what is good in terms of natural desires and Hegel tried to explain the nature of goodness by the perfection of the outcome of his dialectic.

Contemporary epistemological philosophy. As modern philosophy was exploring its crippling tribulations during the seventeenth, eighteenth and nineteenth centuries, modern science (sponsored by capitalism, the other offspring besides modern philosophy of ancient and medieval epistemological philosophy) was advancing, probing ever deeper beneath the perceptual appearance of the natural world, discovering the smaller and stranger bits of matter that help (along with space) constitute what is found in nature. The manifest success of natural science made it difficult to take absolute idealism seriously in the end.

Even epistemologists turned away from Descartes’ starting point. Instead of taking the natural world to be something whose existence had to be inferred on the basis of ideas in the mind, they reverted to common sense and took the existence of a public world for granted. But that did not mean that epistemological philosophy had to be abandoned, because there was another way for philosophers to deploy the same elements that reflective understanding makes present to rational subjects as a theory about the nature of reason. And even if the deeper rational cause it would use to explain the validity of first level arguments did not add any new kinds of substances to be realists about, analogous to the Forms (or God) of the ancient/medieval era or the external world of the modern era, it could hope to avoid the embarrassing excesses of past metaphysics and yet root the arguments of rational culture in a firm, epistemological foundation.

Language is the object of reflection that had been overlooked by earlier forms of epistemological philosophy. Plato had simply assumed that words are simply a way of referring to the Forms that everyone could rationally intuit, making it possible to describe the visible objects by the Forms they imitate. Descartes had recognized that the Forms were just clear and distinct ideas of rational imagination in the mind, but since the same ideas were supposed to be in every rational mind, he could also assume that words are just ways of communicating which abstract ideas speakers were talking about. In both cases, language played a decidedly secondary role to the main objects of reflection by which reason was supposed to know about the world.

Words, and the sentences that they make up, are nonetheless objects that rational subjects are aware of, and they are different from the objects that were central to the ancient and modern theories of reason. Words are perceptible, like other objects in space, when they are spoken or written. But they are unlike other objects in space, because they have meanings and they can refer to objects or properties in the world. To be sure, their meanings had been explained in ancient and modern philosophy by Forms or ideas in the mind. But the words were nonetheless different from them, because they could exist as perceptible objects, and that somehow made it possible for rational subjects to communicate with one another through their animal bodies in a world of objects in space. Thus, to those how accepted natural science, it was plausible to suppose that the analysis of language would provide an explanation of the nature of reason that would explain the validity of all the (valid) arguments of rational level culture (including arguments about natural and social science, practical as well as theoretical arguments, and about what is moral as well as what is in one’s self interest). And it would avoid the pitfall of modern philosophy, for it would not depend on anything that can be known only privately, if the analysis of language rested on a kind of knowledge about language that is inherently intersubjective.

Developments in logic would make language analysis all but irresistible. Given how important mathematics is to the advance of natural science, problems encountered in the evolution of mathematical arguments was bound to focus attention on the nature of formal proofs and logic. As we have seen (in Relations), such developments took place in the nineteenth and early twentieth century, giving rise to symbolic logic and the logical analysis of language (notably, in the work of the early Russell and Frege). Thus, much as natural science was prospering by making use of developments in mathematics, it would inevitably occur to some philosophers that philosophy might prosper by making use of the new developments in logic.

When natural science makes modern epistemological philosophy incredible, therefore, there is another way of doing epistemological philosophy. Hence, our ontological explanation of the nature of reason and consciousness leads us to expect some philosophers to make use of it during a late phase of evolution during the philosophical spiritual stage. That would explain what became known as “analytic philosophy” in Anglo-American philosophy, as we shall see. Much the same explanation might also be given of contemporary Continental and its trajectory toward deconstuctionism, though it will not be pursued here. By the same token, however, ontological philosophy implies that analytic philosophy (and Continental philosophy) are doomed to fail for much the same reason as earlier forms of epistemological philosophy.

Like all forms of epistemological philosophy, analytic philosophy is the attempt to found a theory about the nature of reason on what is known about how we know by reflection (that is, reflective understanding). It may not seem that public language is an object of reflection. Words (and sentences) may seem to be objects of perception, because they occur as material objects in the natural world when they are spoken or written. Indeed, they can be objects of perception along with other objects in space. But that is not how they are seen from the point of view of the rational subject — unless she is a critical realist and recognizes the difference between the immediate, phenomenal appearance of the world in perception and the natural world to which it corresponds. But critical realism is an insight into the nature of perception (and, thus, reason) that had to be abandoned in order to avoid the problems of modern philosophy.

Abandoning the problems of modern philosophy meant giving up the notion that the natural world is something beyond the world in which rational beings find themselves. This did not necessarily mean explicitly embracing naïve realism about perception. But it did preclude making philosophical hay out of the difference between the perceptual appearance of the world and what exists independently of it. Thus, though analytic philosophy did not embrace naïve realism about perception explicitly, most analytic philosophers did take naïve realism for granted in practice, because that is the inevitable effect of abandoning the distinction between the appearance of the world in perception and the world being perceived. Naïve realism is our natural attitude.

Thus, contemporary epistemologists were (or eventually became) naturalists in the minimal sense of believing in the existence of the world disclosed by perception, a world that seemed, at least, to be made up of material objects in space that move and interact over time. Naturalism in this sense is not only the view of natural science, but also the common sense view of the world, the vantage from which the arguments of rational level culture were made.

It was also Plato’s view of the natural world. But unlike Plato, analytic philosophers recognized that concepts are subjective, that is, parts of psychological states on which rational subjects could reflect, using reflective understanding. But they had to avoid making use of such private objects in their theory about the nature of reason.

Naïve realism, however, takes what is actually an object of reflection to be the natural world, and thus, even the public language that is analyzed by contemporary epistemological philosophy is also an object of reflection. To be sure, analytic philosophy thinks of words and sentences as public objects, along with the natural world in which they occur. But since it takes the words to be meaningful, they are actually objects of reflection, and their meanings connect the words to certain objects (or kind of objects) in the world (as their referents). That is the simplest way that reflective understanding can use language as theory about the nature of reason. Once the meanings of words are projected onto the world and appear as public references, it is possible to explain intersubjectively how sentences correspond to the world and to consider the validity of arguments for them.

As a result of naïve realism about perception, images in the brain representing words that are generated by overt verbal behavior are not distinguished from the words that exist as material objects independently of the brain. The images are confused with the material objects themselves, just like the perception of other objects in space. But since the perceptual images of the words are connected with images in the faculty of imagination as their meanings, it is natural to take their meanings to be public as well. That is, the word seems to be related to an object or objects of some kind, as if the semantic relation were a direct, public relationship between the word and object.

This is a theory about the nature of reason based on intuition, for it assumes, in effect, that users of language can intuit their meanings and references.

From our ontological perspective, however, both the words and their meanings are parts of the linguistic structure that is the structure of the spiritual animal under the cultural aspect. As such, they are properties of a material object, albeit a complex material object with a spiritual nature (that is, a organism in which the use of language entails both a social and a cultural structure as a whole). The linguistic structure is a structure of the spiritual animal as a whole, because it is, in principle, contained completely in every member’s brain, as well as in the overt verb behavior by which the use of language coordinates behavior, like the leader’s plan of social level behavior at the primitive spiritual stage.

What are called “abstract objects” are, therefore, just parts of a property of the spiritual animal (or an aspect of an aspect of a spiritual material object), and that gives words (and their meanings) a physical relationship to objects (or kinds of objects), because culture is part of the behavior guidance system by which the spiritual animal acts on other objects in space.

This is not how it appears, however, to contemporary epistemological philosophers, for they do not recognize the existence of spiritual animals. They cannot, because as practicing naïve realists, they do not recognize the existence of a faculty or rational imagination by which words as public, overt verbal behavior (spoken or written) is related to objects (or kinds of objects) in the world. To them it appears that words have a direct, public relationship to objects (or kinds of object), at least, at first.

Analytic philosophy is not always as naïve, however, as it was at first. In thinking about words as public objects, naturalists were forced to recognize that they are just sounds or marks made by speakers, which have only physical properties. But they do have meanings and referents, and if they are not physical properties of words as material objects, they must be explained in some other way. And since there is another way that meaning and reference can be just as public as the words themselves, it was still possible to do epistemological philosophy in the contemporary style. There must be a public way of determining meaning and reference, for otherwise children would be unable to learn a natural language and it would not be possible to translate one natural language into another for the first time.

A less naïve way of analyzing the meanings and references of words recognizes that any images that may be associated with the words are private and that only the words as material objects are public. But it still conflates the perceptual images of the words with the physical tokens themselves, and since the relationship between word and object (and its meaning, whatever that is) must be one that can be established in terms of what is publicly perceived, it assumes that language is governed by public rules. The public rules explain how everyone learns it as they grow up and how it is possible to translate from one language to another.

This is also a theory about the nature of reason that is based on intuition, though it is indirect. The intuition that users of language have is that the meanings and references of words must be determined by public behavior in relation to public objects, if it is not the public rules themselves.

In either case, whether meaning and reference are taken to be inherent in the public words (and sentences) or they are explained by the learning of public rules, analytic philosophy is still basically reflection on language from the point of view of the users of language, and such a reflective explanation makes the analysis of language inadequate as a theory about the nature of reason. The relationship between word and object is not just a relationship of the kind that can appear to the user of language as she reflects an language and how it is used, but one that depends on the nature of the faculties of perception and imagination in the brain and how those brains are coordinated as parts of a spiritual animal.

In either case, meaning and reference are taken to be something intersubjective in the sense that it either is or can be explained in terms of what is public to users of language as practicing naïve realists. That way of analyzing language is the foundation for the theory about the nature of reason used in analytic philosophy. And what dooms it, like other forms of epistemological philosophy, is that it is trying to explain reason by objects that have an appearance to the subject who reflects on how she knows, in this case, the world as it appears in perception to naïve realists and the way that language appears to be public to its users.

What it overlooks is how the relationship between word and object is mediated by a faculty of perception and imagination located in the brain of each user of language. Words have meanings that are images in a faculty of imagination, and their references to objects in the world depend how its representations correspond to aspect of the world — where the latter is explained, as we have seen, by an isomorphism between sequences of images that are called up in the brain over time and the effects of locomotion, manipulation and the like. But the use of reflection (reflective understanding) to think about language as something public makes language appear to have a public relationship to what it represents in the world that does not depend on a faculty of imagination in the brain, but only on intersubjectively correctable rules. It makes the semantic relation appear to be public or determinable by pubic rules.

This is not to deny that there are public rules of language. The analytic philosopher’s talk of such public rules is, in effect, a reference to the spiritual animal. What gives such organisms a “spiritual” natural is the use of language to coordinate the behavior of its parts, and that social level behavior guidance system does depend on representations in the brain that have both a possibly overt verbal side and a necessarily covert nonverbal side. On the covert nonverbal side, images in the faculty of imagination are the meanings of words, and since those images have a geometrically structured relationship to objects in space by way of the animal system of representation, words are made to refer to objects by the connections established in Wernicke’s area between such images and words as verbal behavior. Grammatical markers indicating the kind of activity in the faculty of rational imagination are likewise established in Wernicke’s area, as we have seen. In other words, what is called learning the rules of language is actually just the neurological development of the reflective brain, during which linguistic behavior schemata evolve by reinforcement selection to give the subject the capacity to speak and understand a natural language. It is more basic than rule following. That is, it would be more accurate to say that learning to use language is to acquire the capacity to learn to follow public rules, because rule following, in the sense that is distinctive of human beings, for example, in playing games, is, as we have seen, something that requires the language-based ability to see into one another’s minds (that is, reflective understanding). On our ontological view, public rules are mutually accepted arguments about how one should behave in certain situations of the kind that generate institutions as social level behavior. But none of this is evident to analytic philosophers, because their approach to philosophy is epistemological, with a theory about the nature of reason that comes from reflective understanding.

Analytic philosophy was doomed, therefore, to suffer the same fate as earlier forms of epistemological philosophy, because the relationship between language and the world cannot be explained as a public relationship in that world. Language and the world is a dualism of much the same kind that Plato faced between Forms and visible objects and that Descartes faced between mind and body, because the relationships that appear to hold between these objects in reflection from the point of view of the subject makes it impossible to explain adequately how they are related at all when both sides are taken to be parts of the same, independently existing world. That is, as I have pointed out from time to time, the problem of dualism that epistemological philosophy inevitably causes. Words (and sentences) as linguistic representations, that is, with meanings and references, are not public objects, but representations in the brain of each language user who considers them, and when they are projected onto the natural world, there is no adequate way to explain how they are even parts of the same world.

Analytic philosophy would take various forms, for there are various ways of explaining the nature of language intersubjectively, and different ways of using it as a theory about the nature of reason to explain the validity of the first level arguments of rational culture. But they are all different from earlier forms of epistemological philosophy, because using the analysis of public language as a theory about the nature of reason does not lend itself to any form of realism. It is not obvious that there are any entities beyond those that are immediately present to the subject whose existence and nature could be demonstrated by what is known about language and its relationship to the world, as the external world was for Descartes and the Forms were for Plato. The contemporary form of epistemological philosophy turns out, therefore, to be mostly a foundation for anti-realism, for there are entities and properties that it is possible to be skeptical about. The history of analytic philosophy is, therefore, another story about the discovery of the failure of another kind of epistemological philosophy. And in this case, the inability to construct an argument with a higher level of forensic organization that would explain the validity of the arguments of rational culture. Let us consider some of the main forms that analytic philosophy would take.

Logical positivism. The most obvious way to use the new form of epistemological philosophy is to explain the validity of the arguments of natural science, for even though they may depend on mathematics, they are basically arguments of rational level culture, which use perception and already established beliefs to justify new beliefs. This higher level argument was undertaken by the logical positivists as one of the earliest forms analytic philosophy. They took the most naïve view of language as a public objects, thinking of words and sentences as having meanings that are public, and that seemed to afford a way of explaining the validity of scientific arguments, because both the theories of natural science and the evidence on which such arguments were based were formulated in language. Thus, the logical positivists distinguished between theoretical statements and observational statements. Observational statements were sentences whose truth could be known by perceiving the objects and their properties, while theoretical statements were sentences used to formulate the theories that explained what could be observed. It seemed natural to assume that theoretical statements had to be based on observational statements, given traditional empiricism and its attempt to defend natural science in modern philosophy.

It was hoped that analyzing the arguments of natural science in this way would not only unify the arguments of natural science (the “unity of science” movement), but also explain why they were true in a way that would make clear which beliefs are, and which are not, scientific truths. Moreover, this was a theory about the nature of reason that promised to settle issues in traditional philosophy, for any statements about the world (that is, synthetic, as opposed to analytic statement) that could not be shown to be based on observational statements would be rejected as metaphysics, that is, as meaningless propositions.

Thus, logical positivism used a theory about the nature of language to claim, in effect, that a basically empiricist analysis of the method of natural science explained the nature of reason itself. Less sympathetic critics would dismiss it as “scientism,” because it rejected all the other arguments of rational culture as invalid. That was how they explained the validity of practical arguments: value judgments were cognitively meaningless (though logical positivists did not deny that they were nonetheless useful to express emotions and affect behavior by arousing similar feelings in others). But what brought logical positivism into disfavor among philosophers of science were its implications about natural science.

Theories in natural science commonly refer to entities that are not directly observable, such as electrons, force fields, quarks, and the like in physics. But since they are not observable, the meanings of such theoretical terms could not be analyzed in the same naïve way as observational terms. Only the meanings of observational terms could be explained by the kind of direct, public relationship that seems to hold between word and object that was taken for granted. Thus, the project was to show how theoretical statements are based on observational statements. But since it turned out that theoretical statements are not entailed by observational statements, it led to skepticism about the existence of unobservable theoretical entities.

Since physicists take it for granted that such theoretical entities exist, philosophical defenders of natural science were also inclined to be realists about theoretical entities. Thus, recognizing that they could not derive theoretical from observational statements, they might, as “scientific realists,” still be able to articulate the criterion by which science based them on observational statements. But to make a long story short, any criterion that would include the theoretical entities of science would also include metaphysical entities, unless the criterion was so specific that it was obviously contrived and ad hoc.

Even if a criterion for inferring to unobservable entities could be formulated, however, it was eventually recognized that it would be question-begging. The mere formulation of criterion would not provide any reason believing that scientific arguments for the existence of unobservable entities are valid. What they needed was an explanation of theoretical arguments that would explain why they are valid. A criterion for accepting them as scientific would be merely a principle to be used as a premise in first level arguments of natural science, where the validity of appealing to such principles is what is at issue, at least, judging by traditional philosophy.

The validity of arguments that entail the existence of unobservable theoretical entities cannot be shown by the success of such arguments in the history of science, because that would be circular. It would be using the very principle whose validity is at issue to justify its validity. At best, the history of science can be used to show that science is moving in a certain direction, perhaps, toward a unique outcome (as Kitcher 1992 argues). But even that would not show that what is believed at that ideal end of inquiry is true.

Finally, in the course of such philosophical disputes, the very distinction between theoretical and observational statements began to seem suspect. Since they had abandoned the starting point of modern philosophy, they could not explain the difference between observational an theoretical statements as the difference between ideas of perception and what they represent from the point of view of the subject (that is, parts of the external world). They had to define observational statements as what a normal observer could report from her perception in a given situation. But then it became clear that what normal observers would report depends heavily on their beliefs, and well informed observers would report observing theoretical entities in experimental situations where they were detected. This led to a form of “holism” about meaning, for as Quine would argue, what confronts experience is not individual sentences, but entire theories, worldviews, and even including logic itself.

Logical positivists had also expected to explain the validity of arguments in the science of subjects by showing that they were simply another form of the same empirical methods. The conclusions of a science of subjects are typically formulated as psychological sentences, but the attempt to base them on observational statements led to behaviorism in psychology (thereby justifying Skinner’s operant conditioning). But for those who believe that psychological states are real, it was another form of anti-realism. For similar reasons, logical positivists sided with methodological individualists in their battle with social holists, leading to anti-realism about spiritual animals.

Ordinary language philosophy. There was, however, another way that analytic philosophy would lead to anti-realism about psychological states and spiritual animals, because there was another way of analyzing public language that would account for the use of psychological sentences. Instead of analyzing the logical structure of language and explaining how it corresponds to the world, as logical positivism did, it was possible to analyze the use of language as a practice governed by public rules that children learn as they grow up and by which the use of language can be corrected. This way of using contemporary epistemological philosophy was introduced by the “latter” Wittgenstein in a development that was called “ordinary language philosophy.” The various game-like interactions making up the public phenomenon of language use were “forms of life,” and as Wittgenstein intended, this theory about the nature of reason was mainly negative, a critique of how the first level arguments of the science of subjects are understood even in rational culture.

Wittgenstein’s analysis of ordinary language revealed that language is used for many reasons, not just describing the world. In particular, he saw the use of psychological sentences, not as descriptions of psychological states that are somehow private to each individual, but rather as sentences with behavioral criteria for attributing psychological states to others (or, in the case of first person uses, expressing feelings). They were moves in a game, or part of a form of life that we share. His goal was to show that the problems of modern philosophy had been based on illusion, and thus, that its many problems could be dismissed as mere pseudo-problems. He argued from the nature of language as governed by public rules that there could not be a private language, that is, a language whose terms referred to objects or states that are essentially private, such as ideas in the mind. In the end, therefore, his ordinary language philosophy led to a form of behaviorism, which is called “philosophical behaviorism,” in order to distinguish it from scientific behaviorism, such as Skinner’s theory of operant conditioning, which is supported by logical positivism. Thus, just as logical positivism led to anti-realism, rather than realism, about theoretical entities, so both ordinary language philosophy and logical positivism led to anti-realism, rather than realism, about psychological states.

Ordinary language philosophy lent itself to explaining the arguments of social science, as well as those of a science of individual subjects. After all, it explained language as an interaction among individuals governed by public rules, and if that was an explanation of the nature of reason, it showed the validity of our ordinary way of understanding of institutions and, thus, the reflective science of the social world, which is an inevitable part of the culture of rational spiritual animals. See Peter Winch, The Idea of a Social Science.

Skepticism about metaphysical realism. Logical positivism led to skepticism about the existence of theoretical entities, but as we have seen, logical positivism led to problems that made it possible for defenders of natural science to continue to accept scientific realism. But more recently, analytic philosophy’s theory about the nature of reason has been found to lead to another kind of skepticism, this time, about the nature of the entities described by its theories. Thus, analytic philosophers could concede that theoretical entities exist and still have grounds for more subtle skepticism about natural science, for they could doubt metaphysical realism, rather than scientific realism. (Putnam calls them “internal realists.”) And these doubts could not be dismissed so easily.

Their way of analyzing language also gave analytic philosophers reason to doubt that natural science, even if it was right about the existence of theoretical entities, is correct about their real nature. That is, while the theories of science may not be mistaken by failing to refer to entities of kinds (unobservable or observable) mentioned by them, those theories could still be mistaken in the properties predicated of such entities, including the dispositional properties (described by laws of nature) that are involved in the efficient-cause explanations given by natural science. That means that science might even be mistaken in the causal explanations it gives of what happens in the world. The kind of realism that would be denied in this second way is sometime called “metaphysical realism,” to distinguish it from realism about the existence of the entities mentioned by scientific theories, or mere “scientific realism.” Metaphysical realism holds that science discovers not only the existence, but also the real nature of what exists in the world.

Skepticism about metaphysical realism is justified by a certain looseness in the relationship between language and the world that appears when language is explained in the way that analytic philosophy does. As Quine has argued, analytic philosophers cannot admit that words have meanings that are private to each subject. The meanings of words must be determined by the references they make as public objects to public parts of the world. But when the role of the faculties of perception and imagination in the brain in the semantic relation is ignored, different relationships between word and object (or language and the world) seem possible. Two forms of looseness can be distinguished, an indeterminacy about what words refer to in the world, and an inability to determine which of different possible properties they actually have.

Quine showed the indeterminacy of reference, or ontological indeterminacy, in a famous series of arguments that showed that there are different ways of translating a foreign language using as evidence only the behavior of speakers of the language in certain situations. For example, he showed that “gavagai” in such a language might refer to rabbits, rabbit-parts, or time-slices of rabbits, depending on how other words in the language were translated. That there are always different possible translation manuals based on such observational evidence shows that we are unable, in principle, to tell what another subject is referring to.

Putnam suggests the universality of this kind of argument by appealing to the Lowenheim-Skolem theory. It holds, as we have seen (in Relations), that, for any formal system as complex as set theory or arithmetic, there is an interpretation of all its sentences that makes them true in the realm of natural numbers. Thus, Putnam argues that even if a formal system were constructed that conjoined all the theories of science, including all the observational statements on which they rest, it would still not make its own references to the world determinate.

The other kind of looseness in the relationship between language and the world is the underdetermination of scientific theories by the evidence for them. Putnam makes this argument concretely by pointing to the existence of equivalent theories, or actual theories with different principles that are equally able to predict all the same phenomena. He mentions different forms of geometry (one postulating points and the other spheres shrinking indefinitely), different forms of quantum mechanics (Heisenberg matrix mechanics and Schroedinger’s wavefunction), and different views of the dates and locations of events by observers on different inertial frames (though he recognizes that Einstein’s special theory of relativity provides a single description for them all). But the arguments are all typified by a dispute between Carnap and the Polish logician about how many objects there are in a universe that contains nothing but x1, x2, and x3. Carnap would hold that there are three objects, but the Polish logician would hold that there are seven (or eight, if he counted the empty set as an object). (See Putnam (1987, p. 18ff; 1988, p. 109ff.) Putnam argues that there is no principled way of choosing between such theories and, thus, that there is no truth of the matter about which is true. (Putnam defends a Kantian view that holds that the conclusions of natural science are inevitably determined as much by the nature of the scientists as by the nature of the world they would describe.)

Analytic philosophy supports, therefore, a kind of anti-realism with respect to metaphysical realism. As long as the relationship between language and the world is indeterminate or loose in this way, there is reason to doubt that science discovers the truth about the world, where that means the way that things really are in themselves. Thus, Putnam can taunt defenders of science as foolish believers in “The One True Theory” or a “God’s Eye View of the World.”

Though defenders of natural science may not like to think of themselves as metaphysical realists, neither do they want to accept the “internal realism” that Putnam would saddle them with, for that is to admit that natural science, even at the ideal end of inquiry, may not have described the real nature of what exists. They need a defense against the more recent skepticism founded in analytic philosophy. But the obvious way of defending science from its attacks does not work. A brief account of one more step in the dialectic of contemporary epistemological philosophy will put us in a position to see why philosophical culture inevitably evolves from epistemological philosophy to ontological philosophy.

Since the analytic philosophy’s skepticism about metaphysical realism depends on its way of analyzing language, that is, taking words and sentences to be public objects whose (meanings and) references are determined by the public process in which animals use them in a mutually understood way, defenders of natural science can insist that there is a deeper, naturalistic explanation of the semantic relation. Though they do not have such a so-called “causal theory of reference” worked out in detail, they argue that when it is used to explain the relationship between language and the world, there will no longer be any indeterminacy about reference or uncertainty about which of equivalent theories is true, because science will know what each word and sentence refers to. This is called the “naturalistic” approach to language, and disputes currently rage about how to formulate such a theory.

Such naturalistic theories about language are vulnerable, however, to a rebuttal. The vulnerability comes from the way that even scientists understand the empirical method of natural science (though it can, perhaps, be traced in part to the alliance between science and empiricism in modern philosophy). They assume that the goal of natural science is to discover laws of nature, or more broadly, that it is the attempt to discover the best efficient-cause explanation of what happens in the world. That is why the naturalistic explanation of language is called a “causal” theory of reference. Regardless how science may explain the semantic relation, it will presumably be a causal relation of some kind. It will involve a regularity of some kind that can be described by a law of nature. This leaves defenders of science vulnerable to Putnam’s refutation.

Putnam argues that no such causal theory of reference can possibly eliminate the looseness that analytic philosophy has found in the relationship between language and the world because it will itself by subject to that same looseness. The terms used by a causal theory of reference will admit of different interpretations, which connect them to different objects or different properties, and thus, the indeterminacy about reference will merely be promoted to the level of the causal theory about language. Thus, the dispute about metaphysical realism is a standoff.

The argument between analytic philosophy and defenders of natural science is unresolved, because defenders of natural science do not have an explanation of the nature of reference that would show that Putnam is wrong. Nor do they understand natural science in a way that can show how their theories would escape indeterminacy about their own references. And though scientific realism is generally taken for granted, there is still no justification of inferences to the existence of unobservable entities mentioned by scientific theories. Ontological philosophy, however, would supply all three.

Ontological philosophy recognizes that, because of the reflective foundation of its epistemological argument, analytic philosophy’s explanation of the nature of the relationship between language and the world overlooks the role of the faculties of perception and rational imagination that are part of the brain of each user of language.

If naturalists recognized that brain mechanisms like these mediated the relationship between word and object (or sentence and state of affairs), they would see that reference is not a mere causal relation, but a geometrical isomorphism in space and time between states and processes in the brain, on the one hand, and states in the world. The structure of that correspondence between brain states and the world makes if clear that there is nothing indeterminate about a semantic relation that is mediated by it. It would be clear, for example, that “gavagai” refers to whole rabbits, because the basic structure of the faculty of spatial imagination represents the spatial relations among such objects. (And they would see that language is public because it is a mechanism that coordinates the behavior of individuals in generating social level behavior by coordinating the activity in their faculties of rational imagination.)

Nor is it plausible for analytic philosophers to argue that this isomorphism is itself infected by the same indeterminacy, for it involves not only a spatial isomorphism at each moment, but also a correspondence between sequences of images over time and the structure of space and the geometrical structures of objects. It is sequences of images of the kind that can represent change in the world that represent the possible against which the actual is seen in a faculty of imagination. And though that is a correspondence between images in imagination and the world, it is one that must, by the nature of the mechanism, correspond to what actually happens when the covert behavior operating imagination is overt. There can be no indeterminacy about references mediated by it, once the neurological mechanisms of imagination are understood.

Even without its theory about the nature of language, however, ontological philosophy would enable naturalists to show that scientific theories in general are not subject to any indeterminacy about reference, because it gives an ontological explanation of the validity of the arguments used in natural science (that is, of why efficient-cause explanations are true) that does not admit any indeterminacy. Instead of postulating the substances mentioned by scientific theories (matter, or matter and spacetime), it postulates space and matter, and by recognizing space itself as an ontological cause of their validity, ontological philosophy can show the determinacy of reference, because they all come down to references to particular objects located in a single three dimensional space. Moreover, scientific terms referring to properties will be determinate, because those properties are all explained as aspects of the basic substances constituting the world and how they exist together.

We have already seen (n Relations) how this resolves the problem posed by the Lowenheim-Skolem theorem in mathematics. It also works for the formal theory that includes all the theories and observations of science which Putnam uses.

Nor are there any equivalent theories in science, once the truth of its laws and efficient-cause explanations are explained ontologically by spatiomaterialism. We have seen how both Heisenberg’s matrix mechanics and Schroedinger’s wavefunction can be incomplete representations of bits of matter that really move continuously across space as time passes and that interact in determinate ways.

We have also see how a spatiomaterialist explanation of the truth of Einstein’s special theory of relativity denies that the dates and times assigned to events by observers on different inertial are equally true. One of them is correct and the others false, though it is not possible to tell which one has the truth.

The different ways of formulating geometry all turn out to be true when the truth of geometry is explained as a correspondence to the structure among the parts of space and, thus, among the bits of matter that coincide with them.

Finally, even the dispute between Carnap and the Polish logician is resolved by ontological philosophy, because it turns out that both of them are mistaken. In a spatiomaterial world with three material objects, x1, x2 and x3, there would be four objects: space and the three material objects. (Space can be counted as a single object because its parts cannot exist without one another.) In holding that there are only three, Carnap would be overlooking space, and in holding that there are seven (or eight, if the null class is counted), the Polish logician would be overlooking how space explains all the sets that can possibly be formed of material objects in space.

Even without its explanation of the truth of mathematics and the basic laws of physics, ontological philosophy makes it possible to justify scientific realism. There is a real difference between observational and theoretical statements, because there is a difference between the objects represented in images of perception and those that are not. Some objects to which scientific theories refer are too small, too transient, move too fast, or just not the right kind to be represented in the animal system of representation (such a force fields and photons). But spatiomaterialism justifies inferences to the existence of such unobservable entities, because it explains the truth of the efficient-cause explanations that mention them. Efficient causation is just what happens as a result of the motion and interaction of bits of matter in space as time passes. The observable evidence is the occurrence of certain kinds of events in well understood experimental situations (such as the vapor trail in a Wilson cloud chamber), and given how those events are located in space at that time, there is no other way they could be caused than by the existence of the entities postulated. If some other entity were responsible for what happen, there would be a violation of either the principle of local motion or the principle of local action, because it would have to act from outside the experimental apparatus. Thus, scientific realism has an ontological justification.

This is not a justification of the empirical method as such. It cannot be, since spatiomaterialism is itself the conclusion of an empirical argument, an inference to the best ontological-cause explanation. But it is still a justification of inferences to the best efficient-cause explanations of what happens in the world as a way of discovering basic laws of physics, because such basic laws are descriptions of the behavior of the substances that constitute what is being observed in nature. There is no reason to doubt inductive inferences from particular cases to general laws, because what is being described in the particular case are substances of certain kinds that endure through time and, as substances, they have essential natures that do not change over time.

Naturalized epistemology. The response of most defenders of science to analytic philosophy’s skepticism about metaphysical realism has been simply to walk away from such disputes and simply side with science. This now includes most philosophers of science (according to Kitcher, 1992, and Rosenberg, 1996). They are naturalists who recognize that what they are doing is rejecting philosophy, which they see as the belief that there is a “foundation” or “first principle” that would make it possible for a second order argument to so explain the first level arguments of science in a way that shows their validity. They admit that there is no non-circular way to defend the method of science against alternative methods of knowing, such as religion, new age mysticism, dogmatism, poetry, or literary criticism. For them, it is enough simply to affirm the validity of the empirical method of science and accept the conclusions that it draws about the nature of the world.

This does not mean that they are not concerned with the method of science. They do believe that it ought to be clarified and improved. But they expect to use the conclusions of science itself (discoveries about instruments, about psychological and social processes, and the like) to improve the methods of science. What they deny is that there is any standpoint outside of science from which its method can be judged or justified.

Those who describe and defend this attitude toward analytic philosophy (Kitcher) call themselves “naturalized epistemologists” (following Quine), because they are giving up philosophy and trying to give a naturalistic explanation of all cognitive capacities, not just language.

The evolution of ontological philosophy. There is, however, an alternative. That is shown by the argument presented here. Thus, instead of giving up philosophy and keeping epistemology by doing naturalized epistemology, it is possible to give up epistemology and keep philosophy by doing ontological philosophy. That is, instead of abandoning philosophy, this alternative does philosophy in a new way. And since it is both possible and functional, the evolution of ontological philosophy is inevitable.

Philosophy is a second level argument, that is, an attempt to explain the validity of first level arguments, or rational culture, from the foundation of a deeper cause of their validity. But there are basically two ways of doing this.

The reason there are two ways of doing philosophy is that rational beings have two different ways of understanding causes in the world: naturalistic understanding and reflective understanding. Naturalistic understanding enables them to explain what happens in nature by efficient causes, and reflective understanding enables them to explain how subjects behave by rational causes.

Epistemological philosophy uses reflective understanding to introduce a theory about the nature of reason by which they would explain the validity of arguments of rational level culture. And ontological philosophy uses naturalistic understanding to introduce a theory about the nature of substance by which they would explain the validity of arguments of rational level culture — first, the validity of the efficient-cause explanations of natural science and, then, by way of its implications about the inevitable course of evolution, the validity of the rational-cause explanations of the science of subjects.

One way of putting the difference between then is to say that, whereas epistemological philosophy argues for necessary truths from the wholeness of reason, ontological philosophy argues for necessary truths from the wholeness of the world. That is, epistemological philosophy constructs an argument on a higher level of forensic organization by offering an explanation of the nature of reason that shows how all the kinds of first level arguments are valid. That is to assume that reason has a wholeness that underwrites the validity of all parts of rational level culture. But ontological philosophy constructs such a higher level argument by first explaining how two opposite kinds of basic substances make the world whole. Then, from that foundation, it explains the nature of reason, and its nature and place in the natural world explains the validity of all (valid) first level arguments. But far from explaining the wholeness of reason, ontological philosophy shows that reason, as it is understood by reflective understanding, is not whole, because the arguments of rational culture are divided by at least three basic dichotomies. Thus, instead of trying to explain the wholeness of reason, ontological philosophy makes reason whole.

Though there is another way of doing philosophy, no one is doing it, to judge from what is being published. One would expect naturalists to be trying it out, at least. And if they did, it would be selected, unless these is something seriously wrong with the foregoing, because that would begin the career of ontological philosophy. That ontological philosophy would be inevitable because it is both functional and possible.

Ontological philosophy is functional, because it would not only enable naturalists to defend natural science against the skepticism of analytic philosophy, but as we have seen, it would also do what philosophy as aspired to do all along — to overcome the dichotomies of rational culture and explain how all its (valid) first level arguments are valid.

Moreover, ontological philosophy is obviously possible, because, as can be seen from this argument, it is actual. But that does not quite show that it is possible in the relevant sense, because it does not explain how it can be tried out as a random variation on the arguments that are already evolving at the philosophical spiritual stage.

Unless the defenders of natural science are so committed to naturalized epistemology that they prefer abandoning philosophy to doing philosophy in a new way, the reason that ontological philosophy has not evolved must be that something is has been keeping it from being tried out. Natural science has now evolved far enough with mathematics as its tool and capitalism as its sponsor to overcome the limitations encountered by the Pre-Socratic philosophers of ancient Greece, but there are two causes that may be conspiring to keep it from being taken seriously, one having to do with contemporary naturalism, and the other having to do with contemporary natural science.

As defenders of natural science, naturalists assume that whatever can be known about the substances constituting the world must be discovered using the empirical method of natural science. They are scientific realists in the sense that they believe in the existence of the entities (observable and unobservable) mentioned by natural science. By the same token, however, they are skeptics about the existence of anything whose existence does not have to be posited in order to accept the conclusions of natural science as true. Thus, they let the conclusions of science determine their ontology.

Parsimony is a basic tenet of the empirical method of natural science. In making inferences to the best efficient-cause explanations of the natural world, science assumes that the best explanation is the simplest and most complete, and thus, if two theories have the same scope, it must prefer the one that that postulates the fewest and simplest causes.

Contemporary naturalists are skeptical to the point of being contemptuous of any claims about the existence of something not recognized by natural science. Natural scientists have long allied themselves with empiricism, because empiricism seemed to be the vaccine that would protect science from the embarrassingly implausible metaphysical systems of traditional philosophy.

That does not mean that naturalists reject ontology. They recognize that it is necessary to postulate substances as self-subsistent entities in order to explain the natural world as something whose existence does not depend on the individual rational subjects who know about it. But as defenders of natural science, they believe that the only substances they have to postulate are those that are entailed by the truth of the theories of natural science. Naturalists believe, therefore, that they are already doing everything that can be done with ontology as a way of explaining the truth of scientific theories.

Or to put it negatively, naturalists do not believe that ontology can explain the validity of the arguments of natural science, because ontology depends on those very arguments for its beliefs about which substances exist.

Natural science is, however, overlooking one of the two, opposite substances that constitute the world — or else it affirms the existence of a kind of substance along with matter that makes ontology a problem, rather than an explanation. It denies the existence of space as a substance enduring through time, because that would mean that space is absolute, and that is what contemporary physics rejected in accepting the Einsteinian revolution. Instead, contemporary physics affirms the existence of spacetime, if it affirms the existence of any substances at all in addition to matter (that is, in addition to particles and fields). Though Einstein admitted that his discovery of his special theory of relativity was inspired by empiricism (especially Mach), empiricist skepticism was not necessary for its acceptance. Spatiomaterialism would be excluded anyway by the empirical method of science, especially the form it takes in physics because of the importance of mathematics, and there are two steps to the banishment of substantival space from contemporary physics, one having to do with Einstein’s special theory of relativity, and the other having to do with his general theory of relativity.

When Einstein’s special theory of relativity was first accepted, there were, as we have seen, two theories that could explain all the phenomena covered by it: a theory of the kind proposed by Lorentz as well as Einstein’s theory. But the empirical method of science is to infer to the best efficient-cause explanation of what is observable in nature, and in the case of physics, where mathematics had long since become an indispensable tool, that meant making quantitatively precise predictions of measurements. Thus, when confronted with two highly mathematical theories covering the same phenomena, physicists had to prefer the simpler theory, and that was clearly Einstein’s theory. Einstein needed only two assumptions about the empirical equivalence of all inertial frames in order to derive mathematically descriptions of all the reluctant phenomena (namely, the principle of relativity and the constant value of the velocity of light in all inertial frames).

Minkowski recognized that all the measurements made by all inertial observers could be explained by postulating spacetime, instead of space as a substance enduing through time (that is, absolute space), and thus, when Einstein used the notion of spacetime to explain the nature of gravity, its status as a self-subsistent entity mentioned by the basic laws of physics could hardly be denied. Spacetime had to be a substance for its curvature to be the cause of gravitational acceleration.

This seems to leave naturalists who would consider ontological explanations of the world with a choice between a form of materialism that reduces space to the spatial relations of bits of matter (or to particles and fields, denying the vacuum like a contemporary plenum theory), and a form of spacetime substantivalism (or “spatiotemporalism,” as I called it in Spatiomaterialism) that reduces bits of matter to timelines in spacetime and implicitly denies that there is any unique moment in their careers that is present. In either case, ontology is not able to explain the validity of the efficient-cause explanations of natural science. The former, spatial relationism, affirms only the existence of what natural science already mentions, and thus, as scientific realism already postulates the substances needed to explain its theories. And the ontological explanations built into science would cease to be explanatory, if spatiotemporalism were taken seriously as the ontology of physics, because it denies that any substance endures through time.

Indeed, it is hard to see how spacetime would be used as an ontological cause to explain anything that exists in the natural world, since one of the deepest puzzles confronting contemporary physics is understanding how quantum mechanics, its theory of matter, is even related to Einstein’s general theory of relativity. Current attempts to find a single law of nature that would entail both theories lead to the belief that there are eleven or more dimensions to space!

Naturalists understandably make little use of spacetime in their attempts to understand why the arguments of natural science are valid. And it is easy for contemporary naturalists to settle for the believe in a materialism that affirms nothing but particles and fields, because the view that nature is constituted by a single kind of substance goes back to the beginning of modern science, before Newton. It was defended not only by Hobbes, the most famous materialist of the modern era, but also by Cartesians, for they believed in “extension,” or a plenum of substances whose only essential nature was geometrical structure. Though mind-body dualism was an untenable ontology, the belief that body itself consisted of two opposite kinds of substances would make it even more inelegant.

It is, therefore, possible to explain why naturalists do not take ontological philosophy seriously. Indeed, it is an inevitable result of the empirical method used in physics and the deference that philosophers of science pay to physicists. Though mathematics was an offspring of epistemological philosophy (along with its main sponsor, capitalism), the patent failure of traditional philosophy to provide the deeper justification of natural science (and other arguments of rational level culture) makes the decision of defenders of science to abandon philosophy understandable. But in choosing to naturalize epistemology, they are divorcing themselves from traditional philosophy. And they getting a worse settlement than is possible, because philosophy has a secret treasure stored in its early history, before it started down the road of epistemology.

The Pre-Socratic philosophers had another idea about how to do philosophy. They saw the possibility of an explanation of the wholeness of the world, before philosophy came to be seen as seeking just an explanation of the wholeness of reason. The Pre-Socratics saw how the basic nature of what exists in the world, including its categorical features, could be explained by identifying the basic substances that constitute it. Not only did they discover the concept of substance needed for ontology to be explanatory, but they discovered the best ontological explanation of the natural world as well. However, their ontological explanation of the world could not be convincing, as we have seen, without an adequate theory of the detailed nature of the “atoms” contained by the void, for that is needed to trace the course of evolution, distinguish the various levels of biological and neurological organization, and thereby explain the nature of reason. When philosophers turned to epistemology, the discoveries of pre-Socratic philosophy were forgotten. Though the tool and sponsor needed to discover that detailed explanation were provided by the easier road to philosophy taken by epistemologists, the desperate flight from its failure now threatens to deprive naturalists of what they need to defend natural science.

If, however, the decision of naturalists to take their stand with natural science and stop with scientific realism is caused by the factors mentioned above, then it is possible for ontological philosophy based on spatiomaterialism to be tried out at this point in the evolution of philosophical culture by a random variation on existing arguments. All that is needed is a rediscovery of pre-Socratic philosophy. That would be to take the opposite course from naturalized epistemology. Though it would abandon epistemology, it would be to do philosophy in a new way. But that would give naturalists an ontology that would explain the validity of the arguments of natural science in a way that makes it possible not only to justify the empirical method of science, but also to criticize it. That is, they would have reason to doubt that it is sufficient to infer to the best efficient-cause explanation of what is observed to happen in nature, for they would see that it is possible to infer to the best ontological-cause explanation of what exists in nature as well. This would lead them to consider in a fresh way the possibility of spatiomaterialism, for it is obviously the best ontological explanation of the categorical features of the natural world, including the fact that material objects have spatial relations, that they can change, and that they can change only by motion, not to mention mathematics and the principles of local motion and local action. And that could lead them to acknowledge that spatiomaterialism can explain the truth of both of Einstein’s theory.

Such philosophers of science would then recognize that physicists made a mistake when they rejected Lorentz’s Newtonian explanation in favor of Einstein’s relativistic explanation. They would see that, even though physicists were merely following their empirical method, what physicists gave up for mathematical simplicity was not just the intuitive intelligibility of theories in physics, as if that were a mere subjective bias. What they gave up was a better ontological explanation of the natural phenomena, that is, as we have seen, one that explains more of what is observed in nature with less in the way of substances.

Furthermore, they would recognize that it is possible for spatiomaterialism to explain the truth of Einstein’s general theory of relativity, even though it entails the existence of absolute space. And in the process, they would finally understand how the quantum theory of the other three basic forces of nature are related to gravitation.

If naturalists did that, they would quickly recognize the other consequences that follow from spatiomaterialism, all the necessary truths of ontological philosophy, including the global regularities, the course of evolution, and how it leads up to the discovery of what is represented in the diagram of the wholeness of the world.

Ontological philosophy is, therefore, inevitable. It is possible for such a random variation to be tried out at this point in the evolution of philosophical spiritual animals, and thus, since it is functional, it follows that ontological philosophy based on spatiomaterialism will evolve.

Ontological philosophy will be rationally selected, once it is understood, because as an explanation of the wholeness of the world, it has all possible objections completely surrounded. All the issues currently being disputed in intellectual culture can be located within the structure of its argument, that is, within the diagram of the whole, and ontological philosophy shows how they can all be resolved. When that is recognized, the only issue will be whether ontological philosophy is true, for all those objections to it will stand or fall together.

The evolution of ontological philosophy does not, of course, depend on tWoW.net. It would eventually evolve even if there were no such website, because it is a possible random variation on the arguments that have been accumulated as Western culture and, in spiritual animals that are as populous, healthy and powerful as those that exist today, there are enough rational subjects with the love of argument and the respect for rational judgment to try it out. That much is ontologically necessary — and it will happen in the near future, barring some unforeseen catastrophe that derails evolution at this point, like the impact of another giant asteroid like the one that doomed the dinosaurs.

On the other hand, tWoW.net will not fail to convince rational subjects, even if there are mistakes in the details of some of its arguments, because if it is on the right track, that will be obvious and mistakes can be corrected without upsetting the project as a whole. Thus, it is reasonable to expect tWoW.net to be the random variation whose rational selection will be responsible for the evolution of ontological philosophy — though such a contingent detail cannot be ontologically necessary.

The diagram of the wholeness of the world is, therefore, included in the diagram of the wholeness of the world. Ontological philosophy based on spatiomaterialism is itself something that inevitably evolves in the kind of world that it describes, because the sort of evolutionary change that it entails, given the specific nature of space and matter in our spatiomaterial world, includes the evolution of reason and reason evolves toward the natural perfection of understanding how the world is whole. Thus, reason comes to understand itself as an inevitable product of evolution by reproductive causation.

The rational selection of ontological philosophy is, however, just the beginning of its career. The discovery of an argument that explains the validity of all the arguments of rational level culture will make it possible to sort out which arguments are valid and which are not in every area of inquiry, and that will make it possible to discover what is true much more quickly and reliably than currently seems possible. Many of those discoveries are predictable, including those that have been mentioned in this argument to show the possibility of an ontological approach to philosophy.

The discovery of the true is, however, only part of the significance of ontological philosophy. Reason is not just a cognitive machine. It is an animal behavior guidance system, which uses its knowledge of the true to guide behavior. And reason is the most powerful cause in the world, because it guides the behavior of spiritual animals as well as individual rational subjects. What it does will determine the future course of evolution. Not only will reason take control of biological evolution, with rational selection constraining where natural selection works, but reason will create the other forms of natural perfection that comes to exist during the career of ontological philosophy.

The wholeness of the world is not, therefore, just the wholeness of space or how all the aspects of the world are constituted by two basic substances. Nor is its wholeness that those aspects entail an evolutionary change in which the wholeness of the world comes to be understood by rational subjects. Reason is a part of the world, and thus, it has a role to play in the world. As rational subjects recognize reason as the inevitable product of biological evolution, they will recognize that they are responsible for the future of evolution in their planetary system. What reason will do is not something that reason knows by predicting what it will do. It is something that is known by discovering what reason ought to do.

Some of what reason will do is, of course, predictable. Rational beings will continue to pursue most of the same goals they currently pursue, because those goals are good. And they will use their new understanding of what is true to figure out how to solve all the social, economic and political problems that now seem intractable. These goals are predictable, because they are goals that reason already has.

However, not all of the goals pursued by rational beings are predictable even in this way, because some goals of reason are optional. Some goals are good for reason to pursue because they are chosen by reason. And since not only individual rational subjects, but also spiritual animals can have optional goals, there are aspects of the future of evolution that cannot be predicted even in principle.

Finally, as we shall see, there is one kind of goal that reason can have only because practical reason recognizes, as ontological philosophy evolves in philosophical level culture, something that is so absolutely perfect that it is worthy of worship. Though that is necessarily true, if it is true at all, it is a necessary truth that can be discovered only by practical reasoning.

At this point, therefore, the argument of ontological philosophy must switch from theoretical reason to practical reasons, that is, from arguments about what is to arguments about what ought to be. Knowing the true is only half the way that reason makes the world whole. The other half is how it does what is good.

Ontological philosophy reveals, therefore, that reason is far more important to the world than it supposed, when it assumed that a theory about the nature of reason based on reflection would explain the validity of the arguments of rational level culture. Instead of assuming that reason is whole, ontological philosophy explained how the world itself is whole. That revealed that reason is not whole, but divided by inherent dichotomies. But understanding why rational culture is limited makes reason whole, and as reason recognizes its place in the world, it accepts responsibility for continuing evolutionary progress and making the world itself whole.

Epistemological philosophy of causation. This ontological explanation of change has implications about the nature of efficient causation that solves various problems that have arisen in epistemological philosophy of science, and following them out here may help clarify the significance of ontological philosophy.

More central issues in epistemological philosophy of science, about realism, which arise from its attempt to show the validity of natural science, have already been discussed in describing contemporary philosophy, the last era in the history of epistemological philosophy. We have seen in discussing the philosophical spiritual stage how ontological philosophy would join the issue about scientific realism and metaphysical realism and defend the truth of the conclusions of the empirical method of natural science.

The problems about causation in epistemological philosophy of science fall into two main categories. One arises in natural science about the nature of efficient causation, and the other arises in social science about the nature of rational causation (and, thus, about the basic nature of human society as such).

The difference between natural and social science arises, as we have seen (in Stage 9), from the difference between naturalistic and subjectivistic understanding. It illustrates one of the dichotomies of rational culture that epistemological philosophy has not adequately overcome, and though we already know how it is over come, it may be useful to see how it works out in the context of current discussions in philosophy of science.

Efficient causation. Efficient-cause explanations show that the events and conditions identified as causes produce the events and conditions identified as their consequences.

Efficient causes are different from ontological causes, because efficient causes precede their effects in time (though when both are static conditions, the temporal priority may not be obvious). Ontological causes are simultaneous with their effect, because they produce their effect by constituting them. That is, the existence of ontological effects is part of what already exists in the ontological causes.

Ontological cause explanations are, therefore, self contained and do not call for any deeper explanation. Ontological causes are substances, which are self-subsistent, and the connection between them and their effects is a kind of identity. Ontological effects are identical to parts or aspects of their ontological causes. Seeing the connection between ontological cause and effect is, therefore, just a matter of recognizing that the substances involved have a certain aspect, and as we have seen, the power of rational beings to single out aspects of the natural world is explained by the nature of rational imagination. (Rational imagination includes spatial and structural imagination as well as naturalistic and reflective imagination -- that is, imagination that depends on natural and psychological sentences, respectively).

Efficient-cause explanations, on the other hand, require further support, because the efficient causes and their effects are distinct events or states (or even less general regularities, in the case of reductive efficient-cause explanations). The connections cited in empirical science are laws of nature, which are descriptions of regularities about change that are observed in nature. Though epistemological philosophy of science does not recognize anything more basic than laws of nature, it has recognized, ever since Hume, that something more seems to be required. Efficient-cause explanations call for a deeper explanation.

By efficient-cause explanations, I mean explanations that conform to the "covering law model" of explanation. As represented in the so-called deductive-nomological model, each such explanation is a deductive argument in which the conclusion describes what is explained (a particular event or condition or else a regularity that holds under certain conditions). The premises are of two kinds, laws of nature and descriptions of relevant initial and/or boundary conditions. The explanation depends on deducing a description of what is being explained from the premises, that is, showing them to be instances of the relevant laws of nature.

Something about the nature of efficient causes can be inferred from the standard for judging the best explanation, which is part of the empirical method itself. As we saw in Method, that standard is explaining the most with the least. Applying it to the case of efficient-cause explanations, the best explanations of any given phenomenon is the one that uses the fewest and simplest laws of nature, for that means it uses the fewest and simplest causes. But science aspires to explain all natural phenomena, and thus, more generally, the best explanation is not merely the simplest, but also the one with the largest scope. (There can be tradeoffs between simplicity and scope that make it difficult to tell which explanation is best, though in practice, such conflicts tend to be resolved by further discoveries.) In general, therefore, the goal of science is to discover the fewest, simplest and most general laws of nature that are able to explain all the particular events and conditions (and less general laws) by their efficient causes.

The covering law model is not a very satisfactory explanation of the nature of efficient causes, because it comes down to the nature of laws of nature, and that is no less problematic than the nature of efficient causes. The problem is not solved by discovering the most basic laws of nature (the basic laws of ideal physics), because even at the bottom, there is no explanation of why there is a connection between efficient causes and their effect. There is only the description of a regularity.

In less general branches of natural science, there is nevertheless hope of explaining how efficient causes produce their effects, for it seems possible to reduce them to explanations in more basic branches of science and ultimately to the laws of physics. But this expectation is not satisfied for two reasons. First, the laws and explanations given in physics do not reveal the nature of the casual connection in the most basic efficient causes. And second, many of the laws and explanations of less general branches of science cannot be reduced to those of physics.

As we shall see, the second problem comes down to the first, because the irreducibility of the laws, properties and efficient causes cited in the less general branches of science to physics is a result of the lack of any deeper explanation of the truth of the basic laws of physics.

But first, let us consider the basic laws and explanations of empirical physics and how they are explained ontologically. That will enable us to see how the apparently irreducible laws, properties and efficient-cause explanations of less general branches of natural science can be reduced to ontology, albeit not to the laws of physics.

Basic laws. The most basic laws of nature are the basic laws of physics. They describe relationships between basic quantitative properties that require mathematics to be stated exactly and completely, and what they predict are usually precise measurements that are otherwise unpredictable. Considering their vulnerability to refutation by observation, the success of physics in discovering such laws make it undeniable that physics is on to something real about the world. And the search for the holy grail in physics has been for many decades now the attempt to find a single, most basic law that would include all four of the basic forces of nature (not only electromagnetism, the strong force, and the weak force, but also gravitation).

But as we have seen, its conception of the holy grail shows the limitation of the empirical method of physics. Physics infers to the best efficient-cause explanation of what is observed in nature and uses that to determine its ontology instead of inferring to the best ontological-cause (and best efficient-cause) explanation. It discovers basic laws and affirms the existence of what those laws must refer to, instead of trying at the same time to explain the basic features of the natural world (why bits of matter have spatial relations and how change is possible). But even if there were a single law from which all the other could be derived — and we have seen why that is not possible in our ontological explanation of the truth of Einstein’s general theory of relativity — it would not reveal the nature of the efficient causes.

Ever since Hume, it has been recognized that even though physical laws describe causal connections, there is a problem about what such laws correspond to. As Hume argued, the most that science can know about the causal connections described by its laws of nature is just that certain regularities hold in nature. That does not reveal the nature of the power or necessity by which causes produce their effects. Hume recognized that the problem about causation is not solved by explaining regularities about observable processes by appealing to physical laws describing how their more elementary parts behave, because that merely shifts the problem to the basic laws of physics. Hume was a skeptic who took this difficulty to its extreme, arguing that since all we really know is that certain regularities have so far been observed to hold in nature, we are not even rationally entitled to predict that the same will be true in the future.

Skepticism is not, however, what leads us to expect that, if science were to know the truth about efficient causes, it would be able to explain how efficient causes produce their effects. It is rather that, since laws are just descriptions of regularities, there must be something that makes the regularities true. That is what is offered by an ontological explanation of the basic laws of physics. Even the ontology of generic spatiomaterialism is able to explain some aspects of the regularities described by laws of physics and show them to be ontologically necessary. Consider how the ontologically necessary principle of local motion contradicts Hume’s view that we can never know the necessity of any regularity, but only the constant conjunction itself.xcvii

When one billiard ball hits another, it causes the second ball to start moving. Apart from such events being constantly conjoined in experience, he argued, we could not know anything about what would happen. To an extent, Hume is correct, for experience does tell us that the first ball will not just stop when it reaches the second ball, that it will not bounce back nor go around the second ball and proceed on its way. But Hume is wrong to hold that we can have no knowledge of what is necessary. For if we are spatiomaterialists, we know that the first billiard ball cannot simply disappear from the front side of the second billiard ball at one moment and then simply reappear on the other side at the next moment. The principle of motion does not tell us precisely what will happen, but it does limit the possibilities. But neither does it depend merely on the experience of that constant conjunction. Its necessity depends on our reasons for believing that spatiomaterialism is the best way of explaining the natural world by substances existing in time. Inferring to a deeper kind of explanation of nature than science gives us a foundation for showing the necessity of at least certain aspects of the constant conjunctions that science discovers by inferring to the best efficient-cause explanations.

The principle of local action is also ontologically necessary, and it can also tell us something about the billiard ball that is prior to the experiences of what happens to them that Hume is talking about. Experience of constant conjunctions of events in the past may be the only way of predicting precisely what will happen, but we do know prior to experience that the first ball will not change the motion of the second ball without either contacting it or exerting a force or modifying space in a way that reaches out across space as time passes to affect it. Thus, spatiomaterialism shows that another aspect of the regularities that science knows only from experience of constant conjunctions is ontologically necessary.

What these examples are pointing to, however, is a deeper, ontological explanation of all the aspects of the regularities described by the basic laws of physics. The ontological explanation of the connection between efficient cause and effect comes from showing how the causes and effects are constituted by substances enduring through time. Efficient causes and effects are just aspects of those substances (that is, states of affairs or events constituted by them), and since the natures of the substances and how they exist together as a world constrains what can happen to them, there are certain ontologically necessary truths about how change can and cannot take place. Thus, when space and matter are assumed to have more detailed essential natures, further aspects of the regularities about change are also explained ontologically. That is how the truth of the basic laws of physics were explained ontologically in discussing contingent laws (Local regularities).

Such an ontological explanation of the truth of the basic laws of physics does not, of course, show that they are among the necessary truths proved by ontological philosophy. They do not follow from spatiomaterialism by itself. Instead, the theories about the nature of space and matter that were proposed are, rather, inferences to the best ontological explanation of the basic laws of physics, given the truth of spatiomaterialism. Their role in this argument was to show that it is possible, despite appearances to the contrary from contemporary physics, that the natural world is constituted by space and matter enduring though time as substances.

But even though the basic laws of physics are not ontologically necessary truths, the ontological explanation of why they are true within the constraints of spatiomaterialism is an ontological explanation of the connection between the efficient causes and their effect mentioned in the explanations of physics. It explains the "necessity" of the connection between cause and effect, or the "power" by which the efficient cause produces its effect.

There is, therefore, a way of explaining ontologically the connections between efficient causes and their effects, and as we shall see, the reason that regularities discovered by the less general branches of science are not reducible to physics is its failure to take the role of space as an ontological cause into account.

Irreducible regularities. Even when it was assumed that there is no solution to the problem about the nature of efficient causation in physics, it seemed that efficient-cause connections in less general branches of natural science could be solved by reducing their efficient-cause explanations to efficient-cause explanations in physics. Though that would not solve the basic problem, it would locate all the problems in physics, and the other branches of science could hope to explain the regularities they discovered by those discovered by physics.

On the deductive-nomological model of explanation, such reductive explanations would involve deducing the laws of less general branches of natural science from the basic laws of physics together with relevant initial and boundary conditions. Regularities would be explained in the same way as events or states of affairs, because they would be shown to depend on certain deeper initial and boundary conditions as their efficient causes. This was a project proposed by logical positivists to show what they called “the unity of science.”

Attempts have been made to reduce the theories discovered by less general branches of science, from chemistry and biology to physiology and psychology, to physics. But this project encountered various obstacles. They all involve the discovery of what seem to be irreducible laws of nature.

To be sure, it is often assumed that properties, such as functional properties, can be irreducible in the sense of being supervenient without holding that there are any irreducible laws. But as we shall see, supervenient properties presuppose irreducible laws. It is just that those laws are not the kind that support efficient cause explanations. The regularities they describe have to do with constant conjunctions that are explicitly assumed not to be causal. But they are nonetheless irreducible in the sense of not being explainable by physics, except as accidents.

We will consider the obstacles to reductionism in natural science in three classes, those having to do with thermodynamics, those having to do with mechanical principles, and those having to do with evolution. These problems correspond to three kinds of global regularities, material, structural and reproductive, respectively. Thus, it should not be surprising that what makes it possible to overcome the irreducibility to physics is the recognition of the role that the wholeness of space plays as an ontological cause, for that is what made it possible to explain the global regularities ontologically.

This does not, of course, show that these less general laws of nature are reducible to physics. They still cannot be deduced from the laws of physics and initial and boundary conditions, at least, not in a way that anyone takes to explain the regularity. But it does show that they are ontologically reducible in a spatiomaterial world like ours. That is, they could be explained by an “ontological natural science,” or a natural science in which empirical ontology was recognized to be a more basic branch of natural science than physics, because physics would then formulate its efficient-cause explanations on the assumption that space is a substance enduring through time. In other words, the solution to the puzzles posed by the apparent irreducibility of less general laws of nature does not depend on any of the theories about the more specific natures of space and matter required to explain the truth of the basic laws of physics. What is crucial is only the recognition that space is a substance, because when it is seen as one of the substances constituting the regularity, its nature can be seen as constraining what happens in the world, that is, as an ontological cause. What seems to be irreducible regularities are, in fact, ontological effects, specifically, global regularities.

The advantage of this ontological reduction of physically irreducible regularities is that it takes the steam out of the engine that is currently pulling epistemological philosophy of science toward the acceptance of emergentism, or laws that deny that physics offer a complete efficient-cause explanation of what happens in the world. It shows that the irreducibility of laws to physics is not a reason to suppose that there are other kinds of efficient causes at work in nature. What I mean by this tendency are illustrated by the following examples.

Self-organizing systems. There are thermodynamicists, such as Prigogine (1980), who see the phenomena described by the second law of thermodynamics as evidence of "self-organizing" systems. The systems that are supposed to organize themselves are made of matter, but if matter is doing anything more than obeying the laws of motion and the laws about the attractive and repulsive forces that are recognized by physics, it is hard to avoid the suggestion that it is a holistic kind of matter exerting an emergent force of order in some way.xcviii

Stratification of nature. Emergentism is more explicit in the belief that nature itself is "stratified" according to branches of science, so that the laws discovered in chemistry, biology, physiology, psychology, and social science are each as basic as any discovered by physics.xcix This would mean that every branch of science discovers not only properties, but also laws of nature, that are emergent with respect physics, because to accept the stratification of nature is to assume that there is something sui generis about the laws of each higher branch of science that makes them irreducible to lower level laws (and relevant initial and boundary conditions), or at least not reducible to laws of physics and physical conditions.

Emergent evolutionism. The defense of emergentism has a long history.c A view called "emergent evolutionism" was defended, for example, by philosophers like C. Lloyd Morgan (1920) and Samuel Alexander (1920). They postulated a kind of matter whose essential nature included emergent powers that were supposed to account for the order that exists in nature, including the "new forms of relatedness" that show up in the course of evolution over time at several levels of complexity. Their emergentism is not all that different from "process philosophy," which began with Alfred North Whitehead (1927, 1929) and has been taken up by Charles Hartshorn (1970), Errol Harris (1965), and others. Although they deny that nature is stratified, they assume that what accounts for the apparent truth of the laws of physics as well as the order in nature is a subjective nature that is found in even the simplest particulars.

Chaos theory. Emergentism seems to be what is being suggested by defenders of the recently popular "chaos theory." They point to the way in which random motion and interaction sometimes seems to break out into order to suggest that there is some heretofore unrecognized emergent aspect of matter.ci But instead of defending emergentism explicitly, they are content to present these phenomena in the vein of a mystery yet to be solved.

Second law of thermodynamics. The second law of thermo-dynamics may not seem like an issue in the nature of efficient causation. Its main philosophical implications are usually portrayed as the discovery of the inevitability of the so-called “heat death” of the universe. But since it is a global regularity about change, it does describe states of affairs that are temporally related, like efficient cause and effect, and having seen how it is related to the other global regularities, we can see that it involved in every connection between efficient causes and their effects. Dispositions, such as the shattering of a fragile object, which are the paradigm case of efficient causation, are irreversible structural global regularities, and structural causes doing work are the stuff of which reproductive cycles and their ontological effects are made. To start with the second law of thermodynamic is, therefore, to go the heart of the problem with apparently irreducible laws.

The received explanation of thermodynamics, statistical mechanics, is often cited as a successful reduction of a theory to physics, but it is not completely successful in reducing these laws to the basic laws of physics. It is undoubtedly correct in taking heat energy to be the kinetic energy of the constituent molecules on the micro level, but statistical mechanics is not a reduction of the second law of thermodynamics to the basic laws of physics, because they do not entail that law.

The problem with the materialist reduction of the simplest case of entropy increase can be suggested by a very abstract puzzle about the direction of change in time. The second law of thermodynamics describes a regularity about change that is asymmetrical in time. But all the more basic laws of physics to which it would be reduced are temporally symmetrical. That is, the basic laws of physics can tell us, given the state of a system, how it will unfold over time. But those laws are just as valid for another system, just like the first, except that the objects (and photons) all have exactly opposite momentums. And they imply that the second system will unfold as if time were reversed in the first system. Thus, the basic laws of physics are symmetrical in time. But the second law of thermodynamics is not. It denies that time could be reversed. Entropy cannot decrease over time in an isolated system; it can only increase. The problem is how a time-asymmetrical law can be derived from time-symmetrical laws. This is sometimes called the puzzle about the “arrow of time.”cii It is, as we shall see, the source of Loschmidt’s paradox.

The time-asymmetry of the tendency to randomness has an obvious explanation, according to spatio-materialism, because it is a regular change about the geometrical structures that holds of whole regions of dynamic processes over time. It is plausibly explained by space as an ontological cause, because both tendencies responsible for it are global change in the direction of a geometrical structure that resembles that of space itself. Potential energy becomes kinetic energy which becomes evenly distributed heat. It is the second tendency, the way in which kinetic energy is randomized, that is at issue in the reduction of the second law. What makes the tendency to randomness seem mysterious is overlooking the role of space itself.

Science does not recognize the existence of any substances not entailed by its efficient-cause explanations, and as we have seen, than means that space itself is not taken as a cause in explaining any phenomenon. Instead, physics gets by affirming only the truth of highly mathematical laws of nature and using them to predict quantitatively precise measurements. Though in this case, the mathematics is statistics, it still abstracts from the nature of space. Statistical mechanics is the attempt at a materialist reduction, rather than a spatiomaterialist reduction, and its inadequacy is shown by a paradox described by Loschmidt. The advantage of explaining the tendency to randomness to spatio-materialism can, therefore, be seen in how it removes that paradox.

It was Boltzmann who first showed that random states of closed or isolated systems of material objects could be analyzed statistically. He defined randomness for a gas contained in a box as a statistical equilibrium about the positions and momentums of its constituent molecules. Although the microstate of a gas depends on the positions and momentums of all its molecules, many different microstates are indistinguishable from a macroscopic standpoint, and Boltzmann’s idea was to measure the probabilities of different kinds of macrostates by the number of different microstates that could realize them. This makes sense statistically, if the possible microstates of a gas are all equally probable. But that requires a way of measuring how many different kinds of microstates would realize each kind of macrostate, and so Boltzmann introduced the notion of a six dimensional phase space to represent the state of each molecule in the gas. Three dimensions of phase space were used to represent its spatial location, and another three dimensions were used to represent its momentum in each of the three spatial dimensions, giving each molecule of the gas a certain location in six dimensional phase space. Thus, if this phase space were divided up into very many, equally sized cells, each molecule would be located in one or another of the cells of phase space (the limits of phase space being determined by the total energy of the gas and the size of its container). But since exchanging any two molecules in different cells of phase space would leave the gas in the same kind of macrostate, Boltzmann argued that the most probable macrostate of the gas would be the one in which the number of ways that molecules could be exchanged (or permuted) among the cells is maximum, for it would correspond to the largest number of different possible microstates. That state can be shown mathematically to be the one in which the molecules are most evenly distributed among the cells of six dimensional phase space. In that kind of macrostate, the molecules are said to be in statistical equilibrium.

Boltzmann’s definition clearly refers to the same kind of macrostate that was described in explaining the tendency to randomness, because an even distribution of molecules among the cells of his six dimensional phase space is equivalent to an even spatial distribution in three dimensional space of the three causally relevant factors: (1) the locations of molecules of each rest mass, (2) their kinetic energies, and (3) their directions of momentum. But these are basically different ways of defining randomness. Boltzmann’s definition is statistical, whereas the definition of randomness we have been using is geometrical. And whereas Boltzmann’s explanation is based on the assumption that all the possible microstates of a gas are equiprobable, no such assumption is needed to define randomness as evenness in the distribution of each of the causally relevant factors in real space. That is, instead of using a six dimensional phase space to count possible microstates of certain kinds, we used a geometrical fact about the distribution of causally relevant factors in uniform, three dimensional space not only to define non-randomness, but also to explain why such systems evolve in the direction of randomness over time. The unevenness in the spatial distribution of any of those factors is what causes it to be evened out, because any such unevenness entails that certain (symmetrically interacting) molecules will be in asymmetrical situations, and that will make them interact in ways that tend to equalize their distribution in space. That tendency will continue until there is no longer any unevenness to drive it. It is a change in the geometrical structure of the whole region.

The authority of mathematics may lead some contemporary naturalists to argue that Boltzmann’s statistical definition of randomness is just a mathematically more rigorous way of stating the geometrical definition. But it is not, for his six dimensional phase space is a mathematical abstraction that precludes explaining the tendency to randomness geometrically. To be sure, Boltzmann’s definition of randomness as a statistical equilibrium implies that it is overwhelmingly probable that any system we happen to examine will be random. But that does not explain why the system has a tendency to become more random over time. Indeed, his statistical explanation denies that there is any real tendency toward randomness, if that means that change really has a direction in time, for it holds only that we will almost always find them in random states, if one samples many such systems at many different times. But that does not explain the tendency to randomness by showing that change really has that direction over time.

On the contrary, Boltzmann’s definition of randomness gives rise to Loschmidt’s reversibility paradox. The basic laws of physics are time-symmetrical, which means that, if the molecules all have the same locations, but exactly opposite momentums, change will take place as if time were reversed. That means, as Loschmidt pointed out, that for every non-random microstate that evolves toward randomness, there must be another microstate that evolves toward non-randomness. Indeed, since the statistics by which Boltzmann defines randomness assume that every possible microstate is equally probable, his definition implies that for every non-random microstate that evolves toward randomness, there must be another microstate—the one in which the momentums of all the molecules are exactly reversed—that proceeds towards the non-random state. Changes in either direction should occur equally often. But in fact, we never observe closed systems becoming non-random spontaneously.ciii

The basic source of Loschmidt’s reversibility paradox is overlooking space as an ontological cause. It was Boltzmann who first overlooked space when he argued that randomness is a “statistical equilibrium” about the molecules in the gas. And the reason our ontological explanation does not generate Loschmidt’s reversibility paradox is that it does not have to assume that all possible microstates of the system are equally probable. This is not to deny that, among the abstractly possible microstates that would appear to be random from the macroscopic standpoint, there are some that would evolve into non-random macrostates, if they occurred. That possibility is a consequence of the time symmetry of the basic laws of physics, which we accept as part of the essential nature of matter. But the geometrical explanation need not admit that such microstates ever actually occur as the result of the motion and interaction of molecules that are already random. Nor is that problematic, since no one has ever given a good reason to believe that all mathematically possible microstates are equally probable.civ

Loschmidt’s paradox is a rigorous way of showing that the statistical definition of randomness does not explain the time-asymmetry of this most basic instance of the second law of thermodynamics. We can now see that his reversibility paradox comes from using a statistical approach that abstracts from the geometrical structure of space. Our ontological reduction of the tendency to randomness avoids Loschmidt’s paradox and explains why the change has a direction in time, because instead of relying on mathematical abstractions, it takes the wholeness of space into account as an ontological cause. The material objects (with their kinetic energies and directions of motion) have certain locations in the whole region, and that gives the region the geometrical structure as a whole which is, as we have seen, the cause of the tendency to randomness. Our ontological causes enable us to see intuitively why non-random states tend to become random over time. In the uniform geometrical structure of space, any unevenness in the distribution of causally relevant factors is a geometrical structure about the whole region of molecules that causes them to be evened out. It puts molecules in local situations where their motion and symmetrical, elastic interactions will add up over time in the structure of space to randomness, that is, toward their being evenly distributed on the micro level.

This is not to deny that Boltzmann’s statistical definition may provide thermodynamics with a useful way of measuring randomness (and lack of randomness) or representing them mathematically. Indeed, the confirmation of quantitative predictions of statistical mechanics suggests that it is. But a measure of randomness is not the same as an explanation of why systems tend to become random over time. For that, we must reduce the mathematical representations to spatio-materialist ontology.

This is to resolve one of the anomalies that arises in the program of reductionistic materialism, where it is assumed that regularities are explained by deducing them from the basic laws of physics, initial and boundary conditions, and relevant mathematical theorems. Bus as we can now see, the attempt to give an efficient-cause explanations of the second law of thermodynamics is the mistake. It requires an ontological explanation, that is, an explanation of the same kind that explains why the basic laws of physics are true. Those time-symmetrical laws physical laws are relevant in explaining this time-asymmetrical regularity, but only because they characterize the essential nature of the matter contained in the region of space. It is the how such bits of matter work together with the wholeness of space that explains the tendency to randomness, for as we have seen, it is the geometrical structure about the distribution of any of the three causally relevant factors that puts material objects in situations where their behavior in accordance with physical laws will tend to even out their distribution, resulting in evenly distributed heat. Indeed, geometrical structures about the locations, motions and interactions of the material objects in which entropy can increase are what geometrical structures of material objects must coincide with in order for them to use the free energy to do work.

The explanation of the second law of thermodynamics requires thinking outside the box. In this case, the box is the assumption that to explain is to give an efficient-cause explanations. What does not come under discussion in disputes about the status of the law of entropy increase is the assumption that any adequate explanation must fit the deductive-nomological model. It must be shown to follow from the laws of physics together with relevant initial and boundary conditions. And since there is nothing temporally asymmetrical about those laws (or the initial and boundary conditions), the second law of thermodynamics seems to be irreducible.

The time-asymmetry can be explained ontologically, because it replaces the laws of physics with matter of the appropriate kind and recognizes that they coincide with a substance with an opposite kind of essential nature. Though the regularities in the motion and interaction of such matter in space can be described by laws of physics using the language of mathematics, that is to abstract the local regularities about what happens in a spatiomaterial world like ours and to leave the global regularities behind. By bringing the ontological causes of the laws of physics to the surface, we recognize that they depend as much on the structure of space as they do on the nature of matter. But the structure of space entails its wholeness. All possible spatial relations among bits of matter fit together as part of the geometrical structure of space, and by seeing the distribution of the causally relevant factors (their locations, kinetic energies and directions of motion) against the background of the wholeness of space, we see it as a geometrical structure in the region as a whole. That is to recognize the efficient cause that produces the greater randomness, for it is that geometrical structure that puts material objects in situations where they tend to wipe out the geometrical structure.

To be sure, this efficient cause is what is measured by the statistical improbability developed by Boltzmann. But by abstracting geometrical structure as an arithmetic measure of randomness, Boltzmann hides the connection between this efficient cause and its effect. We can see how the geometrical distribution of causally relevant factors in the region tends to wipe itself out, because we have a factual of rational imagination, which includes spatio-temporal and structuro-temporal imagination, and we understand how the motion and interactions of the material objects tends to change their spatial relations, kinetic energies and directions of motion. As time passes, it adds up in the region to randomness. The connection between the efficient cause and its effect is necessary, because it is caused ontologically by the endurance of these substances through time. But this causal connection cannot be represented in a deductive-nomological explanation, because the only way it can be represented by a mathematical formula, like a law of nature, it as a basic law, like the second law of thermodynamics, which is irreducible to the other basic laws of physics. Hence, there is no solution as long as the only kind of explanation that is recognized to be legitimate are efficient-cause explanations. That is to be locked in the box of the deductive-nomological model of explanation.

Mechanical principles. A less obvious doubt about the reducibility of the causal connections in scientific explanation to the basic laws of physics has to do with the principles of mechanics. The irreducibility of the structural aspects of mechanical principles has been used by Hilary Putnam and others to cast doubt on using physics as the foundation for a complete explanation of the world. Their arguments have contributed to general consensus about rejecting all forms of reductionism. But the problems to which they are pointing are solved by spatiomaterialism. Just as Loschmidt’s’ reversibility paradox arises from failing to recognize how material global regularities can be explained ontologically, these critic are pointing to three problems that arise from failing to recognize how structural global regularities can be explained ontologically. The significance of ontological philosophy is, in part, therefore, the restoration of the good name reductionism.

Putnam’s Board-and-Peg Argument. Many years ago, Hilary Putnam (1975, 296-7) cited a simple regularity that he argued was not reducible to the basic laws of physics as required by the materialists’ reductionistic program. It can, however, be reduced to spatiomaterialism by way of the ontological explanation of structural global regularities.

Putnam illustrated a basic problem about reductive explanations with a simple physical system – “a board with two holes, a circle one inch in diameter and a square one inch high, and a cubical peg one-sixteenth of an inch less than one inch high.” The peg passes through the square hole, but not the round hole. This regularity would not be explained, Putnam holds, even if it could be deduced from the laws of physics governing the behavior of matter in this system.

“One might say that the peg is, after all, a cloud or, better, a rigid lattice of atoms. One might even attempt to give a description of that lattice, compute its electrical potential, worry about why it does not collapse, produce some quantum mechanics to explain why it is stable, etc. The board is also a lattice of atoms, I will call the peg ‘system A’, and the holes ‘region 1’ and ‘region 2’. One could compute all possible trajectories of system A (there are, by the way very serious questions about these computations, their effectiveness, feasibility, and so on, but let us assume this), and perhaps one could deduce from just the laws of particle mechanics or quantum electrodynamics that system A never passes through region 1, but that there is at least one trajectory which enables it to pass through region 2.”cv

Putnam argued that a deduction of this regularity from physics, if it is possible at all, is not really an explanation. What explains why the square peg fits in the square hole, but not in the round hole, is not the basic laws of physics governing the ultimate constituents. It is the higher level structure. All that matters is that “the board is rigid, the peg is rigid, and as a matter of geometrical fact, the round hole is smaller than the peg, the square hole is bigger than the cross-section of the peg.” This explanation would hold regardless of what the peg and board are made of, as long as they are rigid, and so Putnam argues that such higher-level structural explanations are “autonomous” and not reducible to physics. It is our interests, Putnam claims, that make it look as if irreducible higher-order structures like these are causally relevant.

What Putnam is getting at in his example is obviously, however, structural ontological causation. It is just an instance of a reversible structural global regularity, like our example of the box of gas. What is regular in this case is that certain material objects moving and interacting in the region always have unchanging geometrical structures. That is a global regularity, even though all of the global changes are reversible, for it means that the region itself has a kind of geometrical structure that does not change over time. The bare existence of those material structures moving around randomly in the region includes the fact that the peg is sometimes in one hole, but not the other. By denying that the structure of this dynamic process can be deduced from the laws of physics, Putnam is, in effect, making the case for recognizing material structures and the global aspect of space (that is, its wholeness) as ontological causes.

Putnam is not, however, arguing for spatio-materialism. He accepts the materialist ontology, and he argues that these explanations refer to geometrical structures only because “we are much more interested in generalizing to other structures which are rigid and have various geometrical relations, than we are in generalizing to the next peg that has exactly this molecular structure.”cvi That role of special interests is what leads him to argue that “structural features” are a “higher level” that is “autonomous” from physics.

Let me emphasize, however, that space is an ontological cause of this simple global regularity in two ways.

First, the global aspect of space, which is entailed by its structure, is an ontological cause, along with these derivative ontological causes, of the simple global regularity being explained. It connects the geometrical structures of different material objects as parts of the same world and enables them to interact as geometrical structures.

Second, the global aspect of space is an essential ontological cause of the formation of the unchanging geometrical structures of these material objects, since material structures are derivative ontological causes. They are by-products of the tendency of potential energy to become kinetic. And since the spatial relations of the parts of the material object are constituted by the space that contains them, the geometrical structures of the board and peg are not universals, but no less concrete than the material objects that embody them. What enables the board and peg to move across space without changing their geometrical structures is that every region of space contains every possible geometrical structure. It is hard to avoid the conclusion that the anomaly in this case comes from materialists overlooking that space is a substance, because to account for this simple global regularity, all we need is to recognize that space has the same ontological status as matter.

The Supervenience of Dispositional Properties.Other philosophers trying to carry out the materialist reductionistic program have noticed certain anomalies that arise in the reduction of dispositional properties. For example, Bigelow and Pargetter (1987, p. 190) call fragility a “supervenient” property, because it cannot be reduced to the laws of physics.

Properties are said to be “supervenient” when they cannot be reduced to physical properties in the sense of being defined in terms of them. A definition would pick out exactly the same objects by identifying in terms of physical properties what is meant by the supervenient property, which would be another way identifying the same property. But such definitions cannot be given in some cases.

The most obvious are functional properties, such as “being a clock,” which may be realized by objects whose physical structures range from machines worn on the wrist to tree rings, sun dials, and the amount of radioactive decay. There is no way to pick out all clocks by their physical properties, because when one looks for physical properties, one is force to start listing all the different kinds of physical objects that could serve as clocks.

In particular causes, supervenient properties are thought to be identical to the physical properties of the object having the supervenient property. Thus, they hold that any object that is physically similar to one that has a supervenient property must also have the supervenient property. But supervenient properties are not reducible, because it is not possible to describe the physical properties that are both necessary and sufficient for supervenient properties. There are just too many different kinds of cases and no principle by which a list of them can be completed. The reduction involves, at most, therefore, only an identity between the tokens on the two levels, not an identity between types. That is what it means to say that the properties supervene on physical traits.

Reduction would require an identity between the functional and the physical types, or what is called “type-identity.” But since functional properties are supervenient, all the holds is that the functional property in this case is nothing but the physical properties. Since only the token of the functional property is identical to the token of the physical property, or what is called “token-identity.”

In the case of the disposition, fragility, what Bigelow and Pargetter (1987, p. 190) apparently mean by “supervenience” is that fragile objects of the same and different kinds can break up or shatter in different ways in different situations. Different physical properties are responsible for what happens in different cases, and there is no physical property that they all have in common by which all the kinds of cases can all be included.

Supervenience theorists are eager to reassure us, however, that they are not saying that non-physical causes are responsible for the exhibition of such supervenient properties. In each particular case, it is possible, in principle, to explain physically what happened, and any case that is physically like it in all relevant respects will also break up in the same way (or not break up at all). But the disposition is not reducible to those physical properties (and their effects according to basic laws of physics), because there is no natural physical kind or type that is identical to this type of disposition, that is, which includes all and only fragile objects, making fragility a supervenient property.

Physical dispositions can be explained, as we have seen, by spatiomaterialism as forms of structural global regularities. In addition to the wholeness of space, the structural ontological causes of the global regularities are the geometrical structures of the material objects involved and free energy that is supplied somehow by the conditions under which the disposition is exhibited.

What makes fragility irreducible to the laws of physics is the difficulty in identifying the structural cause of the irreversible change in the object before it occurs. A fragile object will break up in different ways, depending on the precise way free energy is supplied under the test conditions. That is because different structural causes are embedded in the same material object. The structural cause in each case is all the parts of the composite object that do not come apart (though breaking up may involve a series of such structural causes), for they are the unchanging structures that determine how objects break up. That is, fragile objects are just machines that use the free energy provided by the conditions of its expression to do the mechanical work of separating chucks of itself from one another. But they are complex machines that do it different ways in different cases, depending on how free energy is supplied.

Does the existence in the material object of many different structural causes generating many different global regularities mean that fragility is a supervenient property? That can’t be correct, for if it were, we wouldn’t be able to see how all the global regularities are alike. And we can. Given that the bonds among the parts of the object are inelastic and cannot absorb much of the free energy supplied by the impact, we can see how the forces are communicated by their bonds and spread out geometrically so that whole groups of bonds break together or not at all. For example, we can see why a wine glass dropped on concrete will shatter, but when dropped on a rug which absorbs some of the initial shock, it is more likely to break at the stem. What happens is just a result of how the motion and interaction of bits of matter add up in space over time, including how forces are communicated among the parts of the fragile object, and with our capacity for spatio-temporal imagination, we can “see” the similarity about what happens in each case. The similarities among cases of objects breaking up under impact (including different kinds of fragile objects) are basically geometrical, but nonetheless real. Thus, there is a type-type identity between the ontological causes and the disposition (or global regularity) they determine.

Supervenience is just an appearance that a spatiomaterialist world has because science seeks only efficient-cause explanations. What makes fragility seem to be irreducible is the assumption that the reductive explanation must be formulated as a deductive argument from laws of physics together with initial conditions and mathematics theorems.

The basic laws of physics are local regularities about change that are constituted jointly by space and matter. They depend on the structure of space as much as the essential natures of the forms of matter contained by space. Thus, when the laws of physics are taken as basic in an efficient-cause explanation, only some of the relevant aspects of the ontological causes are represented. The structure is space is included only insofar as it helps constitute the local regularities described by the laws, but that is to abstract from the wholeness that is also entailed by the geometrical structure of space. The wholeness of space is just as relevant to how change unfolds over time as the aspects of space that are represented by the laws of physics. It includes all the geometrical aspects of the motions and interactions of the bits of matter that add up over time to a certain structural effect. But the wholeness of space is excluded, according to the deductive-nomological model, from efficient-cause explanations.

It is not easy to translate the geometrical factors that are relevant such an ontological reduction of dispositions into mathematical formulas that can be used in conjunction with the laws of physics to derive a description of the breaking up or shattering. The motion and interaction of material structures do not add up to simple quantities, like those involved in the conservation of momentum and energy. They add up to geometrical structures. But limitations in the capacity of mathematical formulas to represent geometrical structures should not be taken as grounds for denying their role or the role of the geometrical structure of space itself in the ontological reduction of dispositions.

It is not necessary to construct deductions using mathematical formulas, because the cause that explains the kind of structural global regularity is a material structure and how its motion and interaction add up in the wholeness of space, and that can be understood by using spatio-temporal imagination. It is a matter of seeing how the forces imposed by the impact are communicated to other parts and how they build up in certain locations. Insofar as the structural effects depend on quantitative aspects, such as the strength of the forces and the distances over which they are exerted, they can be approximated by computer models that take into account both the forces and the geometrical structures of each molecule or atom and their spatial relations to one another in the composite whole. This is, of course, how materials science has been explaining the properties of bulk matter ever since computers became widely available. The capacity of computer simulations to do what formal mathematical deductions cannot do is evidence of the relevance of the geometrical structures of the material objects and the geometrical structure of space itself as ontological causes of these global regularities.

Fragility and other such dispositions are, therefore, supervenient properties only in the sense that they cannot be deduced mathematically from the basic laws of physics together with appropriate initial and boundary conditions. But they are not supervenient relative to our ontology, because when we recognize that the dispositions are constituted by bits of matter that coincide with space as a substance, we can see how the wholeness of space so constrains the motion and interaction of the material structures that they add up over time to global regularities of certain kinds.

The example of fragility is complicated by the fact that one of its ontological causes is derivative. Material structures are not basic ontological causes, but depend on the tendency of potential energy to become kinetic, and fragility is a disposition in which the very existence of the ontological cause is at stake. It involves, in other words, the generation and corruption of (derivative) substances in our ontology, and thus, is special in way that parallels the generation and corruption of primary substances in Aristotle’s ontology.

The complication about generation and corruption encountered in the case of fragility is, however, general, for it holds of chemical interactions generally. They are unlike the interactions in which molecules serve as catalysts (or enzymes), for in those cases, the molecules have geometrical structures that persist through the change, making them ontological causes. But in chemical interactions, molecules have geometrical structures that contain many different structural ontological causes, like fragile objects, because their global regularities also depend on how the free energy that drives the irreversible processes is supplied.

A typical chemical interaction involves an exchange of clusters of atoms between two original molecules that result in two new molecules. Their shapes determine how the original molecules fit together and, so, which parts of each molecule interact with which parts of the other, and the total force exerted at such moments determines whether or not the molecules will interact chemically and exchange subgroups of atoms, forming new kinds of molecules. The free energy comes from the potential energy of the forces that parts of molecules exert on one another, but it is structured by spatial relations among parts that are not changed.cvii The structural causes in these cases are the clusters of atoms (or smaller molecules) that do not change their geometrical structures during the interaction, since only unchanging geometrical structures of matter are ontological causes. Thus, molecules will contain different structural causes depending on which other kinds of molecules are combined with them. But that does not mean that chemical interactions are supervenient properties or otherwise ontologically irreducible, at least, not when we recognize that substantival space is an ontological cause.

Putnam’s Argument from Countervailing Conditions. Although Putnam does not say that they are supervenient, he also argues that dispositions are often irreducible. His reason is that they are tendencies that hold only “other things being equal.” Putnam (1987) illustrates the irreducibility of disposition by considering the solubility of a sugar cube in water.cviii

It might not dissolve when placed in water, he argues, because the water might already be saturated with sugar. Or because the water might freeze before the cube can dissolve. Finally, he appeals to Loschmidt’s reversibility paradox as a countervailing condition. The water might happen to be in a state that is the exact time-reversal of a state that occurs when a larger cube was dissolving, so that the motions and interactions in this special case make the cube un-dissolve out of the water and form a crystal.

It is materialist reduction that Putnam is talking about, for the irreducibility of these disposition comes from trying to deduce them from premises that are “formulas in the language of fundamental physics”cix which cannot take into account of all the various exceptional conditions that might prevent the expression of the disposition. On the deductive-nomological model of explanation, the only way to predict what will happen is to trace precisely the motion and interaction of all the objects in the region over a region of time and see where it leads, and Putnam denies that all the conditions that might be relevant to the exhibition of the disposition can be included in such a deductive argument.

The dissolving of the sugar cube in water is, according to the spatiomaterialist reduction, just a structured thermodynamic process. The free energy is the potential energy that comes from the forces that would form weak hydrogen bonds between the sugar and water molecules. The structural causes are the shapes of the water molecules, the shapes of the sugar molecules, and the material structure that results from packing sugar molecules together in the crystal.

In dissolving, weak bonds holding sugar molecules together in the crystal are replaced by weak bonds with water molecules as a result of their random motion and interaction with one another in the region. Opposite electric charges on opposite sides of the water molecules fit with similar charges on sugar molecules in such a way that the sugar molecules exchange their bonds with one another for stronger, less energy-rich bonds with water molecules, freeing kinetic energy in the process. Thus, when their random motion and interaction brings these molecules together, sugar molecules are released from their bonds in the crystal to form bonds with water, and a new kind of static order comes to exist. That is how matter, as energy, flows through geometrical structures from potential energy to evenly distributed heat in this case.

Putnam’s doubts about reducibility come from the impossibility of including countervailing conditions in the deduction. But if the disposition is recognized to be a global regularity, there can be no countervailing conditions that are not taken into account, because all the bits of matter in the region are involved in how their motion and interaction add up over time.

If what prevents the sugar cube from dissolving is that the water is already saturated with sugar molecules, it is simply the absence of the free energy in the region that the material structures use to do the work of freeing them from the crystal. The potential energy depends on certain spatial relations between the molecules exerting the forces, and since all the water molecules in the region are already bound to sugar molecules, the relevant spatial relations do not exist, and so there is no thermodynamic flow of matter from potential energy to evenly distributed heat to be structured. That condition is already taken into consideration, if it is explained ontologically as a global regularity by structural causes and the global aspect of space.

On the other hand, if what keeps the sugar cube from dissolving is a sudden freezing of the water, that is also something that is already taken into account by treating it as a global regularity. Global regularities are regularities about whole regions of space, and that means they must either be closed or else one must keep track of what is flowing in and what is flowing out of the region. Although a sudden freeze would certainly stop the irreversible special theory of relativity, there is no way it could happen unnoticed. Heat is a form of matter (that is, kinetic energy is explained ontologically as kinetic matter), and as a kind of substance, it cannot simply go out of existence. The tendency to randomness spreads heat throughout the region, and it can be removed from the region only if there is something colder in the region to which it can flow. That would be a thermodynamic flow of matter toward evenly distributed heat in the region that is clearly relevant in explaining the dissolving as a global regularity. Finally, nothing outside the region could make it freeze without violating the principle of local action. Thus, a sudden freezing is not an exception to an explanation of dissolving as a structural global regularity.

The final countervailing condition Putnam mentions is not explained by this reduction to spatiomaterialism, for it is just an illusion that comes from the attempt to carry out a materialist reduction of the tendency to randomness. Putnam is using Loschmidt’s paradox as a countervailing condition. But as we saw in the last chapter, when the tendency to randomness is explained geometrically, rather than mathematically, by statistics, there is no reason to believe the water and sugar molecules would ever be in a microstate that corresponds to one in which the sugar cube is dissolving except for all the molecules having exactly opposite momentums. Only the statistical definition of randomness requires us to believe that all possible microstates are equally probable.

None of the countervailing conditions to exhibiting solubility that Putnam mentions would be overlooked, therefore, by an explanation of this disposition as a global regularity, because when the global aspect of space is recognized as an ontological cause, the whole region where it occurs is causally relevant. Dispositions are not properties inherent in the nature of matter, but rather kinds of structural global regularities, which depend on structural causes, free energy supplied by a thermodynamic flow of matter toward evenly distributed heat, and a region of space where their geometrical structures coincide. What makes it seem that exceptional conditions preclude the ontological reduction of dispositions is the assumption that a reductive explanation must deduce a description of the regularity from “formulas in the language of fundamental physics,” as if the disposition had to follow from the basic laws of physics without taking account of how structural causes can channel the thermodynamic flow of forms of matter toward evenly distributed heat in the region. The role of space in imposing those regularities may make it hard to formulate these ontological explanations as deductions, but the reduction to the ontology of spatio-materialism leaves no room for surprises.

Finally, other apparently irreducible phenomena can be explained in similar ways.

Prigogine (1980), for example, points to the phenomenon of self-forming objects as irreducible.cx He recognizes that it does not occur when entropy is maximum, but depends on open systems, in which there is a flow of mass and energy (so-called “dissipative systems”). But far from being an anomaly, this kind of phenomenon is entailed in a spatiomaterial world like ours, because self-forming objects are just instances of the tendency of potential energy to become kinetic.cxi See the discussion of crystal formation and the conformation of protein molecules in Structural global regularities.

“Chaos” is likewise cited as evidence of emergent phenomena. These are situations in which structural global regularities suddenly appear from apparently chaotic, or random, dynamic processes, such as a turbulent flow suddenly becoming highly structured. What makes them seem inexplicable, however, is failing to take space into account in one way or another, either by not recognizing the structural causes at work in the region, by not taking the geometrical structure of the boundary conditions of the system into account, or by ignoring the structure of the space within those boundaries. When they are taken into account, it is not surprising that the quantitative aspects of the motion and interaction of bits of matter in the region would fit together geometrically with those spatial structures so that their motion and interaction add up over time to certain regular, repeated patterns.cxii They are just structural global regularities. The anomalies all come from overlooking structural ontological causes and how they work together with the global aspect of space.

Functions. The recognition of supervenient properties is the most common way of describing the failure of reductionism, cxiii and functional properties are the example that has forced philosophers of science to recognize that some properties are supervenient. The main problem is that they may be realized by indefinitely many different and seemingly unconnected sets of physical traits, as illustrated by such artifacts as clocks. As we have noted, clocks may be realized by objects whose physical structures range from machines worn on the wrist to tree rings, sun dials, and the amount of radioactive decay. Artifact are a special case, which is one sense are not so problematic, because we know that they depend on the intentions of subjective beings. In another sense, they are more problematic, because it requires the reduction of intentions. However, functional properties also play an enormous role in biological, where they pose a similar problem. For example, hearts are mechanisms for circulating energy in multicellular organisms, but they cannot easily be picked out by their physical properties, because they vary from simple gastrovascular cavities to elaborate circulatory systems with arteries and veins involving one or more hearts of various kinds.

There is no general agreement about the significance of the existence of supervenient properties. At one extreme, they are considered a way of defending physicalism against the claims that there are processes that cannot be explained in terms of the laws of physics. At the other extreme, they have attracted other philosophers of science toward emergentism, is the sense of the belief that there are laws in less general branches of science that cannot be reduced to physics.

Though supervenience theorists generally deny that upper level laws mentioning supervenient properties are irreducible, supervenient properties do entail a kind of law that is not reducible.

Supervenience theorists insist that the causal connections in which supervenient properties may be involved can always be explained by the physical causes that are responsible for the regularity in that case, though, of course, those physical causes vary with the kind of physical properties that realized the supervenient property in that case. They are right to deny that there is any need irreducible causal laws (that is, laws that can be used to explain events by efficient causes). No one believe that clocks or hearts require anything but physical laws for their operation.

Even so, however, the reduction of the less general regularity to the laws of physics is not complete, because the physical explanation of what happens in each instance of a supervenient property does not explain the indefinitely large variety of different sets of physical traits that may realize the supervenient property. In other words, the grouping of those cases in such a way that they all have the same supervenient property is itself a regularity that has not been explained. If supervenient properties are anything more than purely subjective projections onto the world, then the fact that such physically diverse objects can be grouped together in describing upper level regularities is something that needs to be explained in the end. That regularity may not be a law of nature in the sense of a law of nature that supports an efficient cause explanation (according to the deductive-nomological model). But it does imply the existence of an order of some kind about the world, and that order cannot be reduced to the laws of physics and conditions described in physical terms.

In the case of functional properties, furthermore, the prime example of supervenient properties, there is even more reason to suspect that there are irreducible laws of nature, because functional properties are typically used to give functional explanations. It is not just that certain organs in multicellular bodies are all have the function of circulating energy to all parts of the body, but that the existence of such organs seems to be explained by that function. But if functions are causes that can explain the traits that have them, it involves causal connections like those in efficient causes. The function is a different event or condition from the trait it would explain, just as the efficient cause is different from its effect.

It is certainly not like the connection between an ontological cause and its effect. The function is not constituted by the trait described physically. If it were, there would be nothing supervenient about the functional property. Instead, traits are said to “realize” the function, because there are many different ways that functional properties can be realized. But that makes it even more mysterious how the function can be said to explain the trait, since the same function can be served by physically different traits.

Furthermore, since a functional explanation explains the trait by the function, it would not help to discover that the trait constitutes (or realizes) the function, because the function must be prior to the trait to “cause” it. And that would require explaining where the function comes from or how it could make material objects have the physical properties that would constitute them.

The prior issue is, therefore, whether functional explanations in biology are valid and, if so, how. Though most philosophers are inclined to believe that they are valid in some sense, there has been no generally accepted defense of their validity. The received view is that they are really just disguised historical explanations of a contingent process of selection, which do not justify prediction of the traits that will evolve.cxiv But if evolution is a global regularity in a world of matter and space in time, there is a sense in which they are valid explanations.

There is, of course, no question of functional explanations being valid, if that means that the function is a substance that acts on matter to give it the trait, that is, to give it the physical properties that enable it to serve the function. That is the kind of causal connection entailed by Aristotelian teleology, or what is called “final causation.” Aristotle believed that having an essential form would make natural change take place in the particular substance for the sake of an end, final cause, or telos, which is said to be good for substances of its natural kind. Naturalists have long since recognized that there are no essential forms in the natural world that work in the way Aristotle supposed. That is entailed by materialism about the natural world, which has prevailed since the beginning of modern science, and essential forms acting as final causes are not among the substances assumed by spatiomaterialism.

The validity of functional explanations. The validity of functional explanations in biology is, however, entailed by ontological philosophy, and the way in which their validity is explained, confirms their validity in a far stronger sense than is currently recognized. Functions do cause the traits that serve them, and if evolution is due to reproductive causation, functions explain why organisms have the traits they do in a way that makes it possible, in principle, to predict that the traits will evolve.

That is not to say that every physical property of the traits is predictable. The traits usually involve some physical properties that could be otherwise. But enough of the physical properties of the traits are determined by their functions that they can be recognized by their physical properties in the organisms.

Evolution is due to reproductive causation. That is, evolution is a global regularity that is explained ontologically as the kind of change that is constituted by reproductive cycles and the wholeness of space. The reproductive cycles are material structures of a certain kind using the available free energy to go through cycles in which they both reproduce and do non-reproductive work that controls conditions that affect their reproduction. The regularity about change in the region over time includes , as we have seen, both a gradual change during each stage in the direction of maximum holistic power for organisms of their kind (or their natural perfection) and a series of evolutionary stages in the direction of the natural perfection of life itself.

Since reproducing organisms impose natural selection on themselves (by the scarcity caused by generations of reproduction in space), what is regular about change in the region over time is that every possible increase in the power of the reproducing organisms is necessarily made actual as it becomes possible. Each random variation of their structures that is acquired because it controls some condition affecting its reproduction is a trait. Its function is to control the relevant condition. And since the conditions that it is possible for random variations on evolving organisms to control are “in the cards,” so to speak, they can, in principle, be used to predict the traits that will evolve.

Likewise, for the revolutionary episodes. The higher levels of part-whole complexity in the structures of the reproducing organisms that can be tried out at each stage of evolution depend on the natures of the reproducing organisms that already exist, because they must originate as a radical random variations on existing structures. And whether they can control some relevant condition that was previously out of reach depends on the nature of the region where conditions affect their reproduction. That is also “in the cards,” so to speak, and since both the possibility and the functionality can be known, the stages of evolution are, in principle, predicable. Thus, once again, even higher levels of structure in reproducing organisms can be explained by the function that it is possible for such structures to serve.

Actual predictions of the new traits that occur in gradual evolution by their possible functions would require the capacity to imagine every possible random variation and to see what condition those secondary effects would control, and that is usually not possible. Thus, it is only after the change has occurred that we are usually in a position to see which possible function was responsible for the trait's evolution. But in the case of revolutionary evolution, it is easier to see the possible functions of new kinds of primary structures, and that is the kind of functional explanation that was used to trace the course of evolution in the previous section.

This ontological explanation of evolution as a global regularity entails, in other words, a necessity about the kind of change that takes place over time in the region of space. It is a kind of regularity that makes prediction possible, in principle.

This is formally similar to the explanation of dispositions and ordinary causal connections between events described in the last chapter, for those regularities were also global regularities explained by matter and space as ontological causes. In dispositions, the event ordinarily called the “cause” is typically the way free energy is supplied, and the irreversible change that takes place is the effect.

In this case, however, reproductive causation necessarily makes every possible increase in the power of primary structures actual, and given the meaning that "function" has ontologically, that means that it necessarily makes every functional trait that is possible actual. Possible functions are, therefore, the cause of the evolution of certain kinds of secondary effects in much the same sense that compressing and releasing an elastic object causes it to spring back or putting a sugar cube in water causes it to dissolve. The evolutionary changes that make it possible for the random variations on reproducing organisms being tried out to be functional in a new way are what causes that trait to evolve.

Though functional explanation are valid, the functions are not essential forms with causal powers, as Aristotle assumed. In Aristotelian teleology, functions are assumed as a basic principle (if not substance) of the ontology, and thus, their causal powers are not explained, but merely assumed. But in evolution by reproductive causation, the ontological causes are the kinds of space and matter that exist in a world like ours, for they are the ultimate ontological causes of reproductive global regularities.

The ontological reducibility of functional properties. The predictability of traits by their functions should remove any doubts about the reducibility of functions or functional properties to the ontology of naturalism. Doubts about their reducibility come from the understanding that contemporary Darwinists have of the causes of evolutionary change. They are, as pointed out in the explanation of reproductive global regularities, accidentalists. They think of natural selection as being imposed on living organisms from outside by unpredictable changes in their environment, and they worry about the availability of random variations to meet the new conditions in the best possible way. For them, in Kauffman's (1993) words, evolution merely "cobbles together jury-rigged contraptions.”

This view of evolution is another example of the effect of overlooking the wholeness of space as a cause of regularities about change over time, for instead of seeing evolution as the way that reproductive cycles add up in space over time, it sees evolution as driven by an externally imposed natural selection. Thus, it seems to contemporary Darwinists that different traits might have served the same functions. Since that means that there is no necessary connection between functions and the traits that serve them, functions are said to be "supervenient properties" relative to the physical nature of the traits that have them.

But if there is a necessary connection between the functions and the traits that serve them, as implied by their status as consequences of spatiomaterialism, then functional properties are, in principle, reducible to the ontology of naturalism. This is to reduce functional properties to our ontology in much the same way that we reduced dispositional properties, except that the relevant global regularity depends on reproductive causation, rather than structural causation.

It is the progressiveness of evolutionary change that entails the validity of functional explanations and the ontological reducibility of functional properties. From the beginning, I have described evolutionary change as change in the direction of natural perfection, and I have distinguished various kinds of natural perfection: the natural perfection of the organisms at each stage, the natural perfection of their combination in the ecology, and the natural perfection of life in the series of stages of evolution. Even evolutionary change itself has a kind of natural perfection about it because of the way that what happens at each moment contributes to the progress.

The direction of evolutionary change was called “natural perfection,” because it always involves a maximum holistic power and that is the kind of part-whole relation that is optimal in a spatiomaterial world. It is “natural” perfection, because it is the kind of perfection that is appropriate in a natural world.

Though it depends on the thermodynamic flow of matter from forms of free energy to energy bound as evenly distributed heat, nothing can structure thermodynamic order except material structures, and reproductive causation is making the most of structural causation by shaping reproducing organisms to be as powerful as possible in using the available free energy to control conditions in the world. To be sure, until the evolution of reason, organisms acquire only those powers that control conditions that affect their own reproduction. But that is simply what is required for structural causes that are maximally powerful to exist in a world of matter and space in time. No structural causes, regardless how powerful, would last very long, if they did not use their power to ensure their own existence. Organisms do that in a way that makes them as powerful as possible, and rational beings do that because it is good.

The natural perfection produced by reproductive causation made it possible to explain goodness as contributing to natural perfection. Each part of such optimal part-whole relations makes a necessary contribution to its maximum holistic power, and thus, each is good in the sense of contributing to the natural perfection of the whole of which it is part. And as we have seen, this explanation is a definition of “good” that vindicates all our deepest and firmly held convictions about what is good and bad (and about what is right and wrong).

By this definition, goodness and perfection are related to one another as the property of the part is to the property of the whole in the products of reproductive causation. When the whole is perfect, all the parts are as good as they can be, and when all the parts are as good as they can be, the whole is perfect.

Moreover, it follow that the function that each non-reproductive structural effect has is good for the organism of which it is part, that each kind of organism is good for the ecology of which it is part, and that each level of organization in the structures of organisms that comes to exist with new stages of evolution are good for what exists in the whole region in which evolutionary change is happening. Ultimately, therefore, there is one whole on the planet (or planetary system) to whose perfection all the good parts make a necessary contribution.

To be functional is, therefore, to be good. Since their functions explain the traits that evolve, what explains the traits that organisms have is their goodness. The goodness of the random variations is what explains why they are naturally selected. Likewise, since what explain each new stage of evolution is the functionality of its higher level of part-whole complexity, what explains each new stage of evolution is its goodness. The goodness of the higher level of organization is what explains why it is naturally selected. This connection to the nature of goodness is another way of saying that evolution is progressive.

Rational causation. The remaining problems about the nature of causation arise in the branches of science known as psychology and social science.

Psychology has to do with the explanation of individual behavior, and that is problematic mainly because we know too much. As rational beings, we have a special way of seeing into the minds of other rational beings (and subjective animals generally). We ordinarily explain individual behavior by the reasons that the individual has for it, that is, the beliefs, intentions, desires and the like that are responsible for it, or subjectivistic understanding, as we have been calling it. There are two problems,

One problem in this field is that rational explanations do not seem to be the kind of explanation that a branch of natural science ought to be seeking.

But another problem is that, even if they are, they do not seem to be reducible to the kinds of explanation given in physics.

The social science have to do with the explanation of social phenomena, or what has been explained here as the behavior of spiritual animals. We know that human societies are different from other groups of animals, because our capacity for subjectivistic understanding gives us an “inside view,” so to speak, of the phenomena. However, that view is not based on perception and, thus, is not from the vantage of natural science. Thus, there is a problem about the nature of the object that is being studied by the social sciences.

The problem about reductionism in this case is just opposite to the other cases considered here. Though there have been social scientists, like Comte and Durkheim, who thought that societies are not reducible to the individuals, that view is not common these days. Contemporary naturalists tend to assume that social phenomena must somehow be explained in terms of the individuals who make up human societies, because they do not see how there could be any relevant causes that arise from the nature of society as a whole.

The main philosophical problems about the nature of causation in social science has to do, therefore, with showing how social phenomena can be explained as a result of the nature of the individuals, the regularities in their behavior, and the situations in which they act. The project of explaining social phenomena in that way is called “methodological individualism,” and its most popular current form is sociobiology, which bypasses individual psychology and tries to explain social behavior by genes that have evolved in individuals.

The ontological explanation of the nature of change provides, however, a solution in all of these cases. Though the laws of nature (or regularities) discovered in psychology and social science may not be reducible to the laws of physics, they are reducible to the ontological causes recognized by spatiomaterialism in a world like ours. Once again, the reason is the failure to recognize that the global regularities are caused ontologically by the wholeness of space and other substances contained by it, both basic and derivative, like material structures and reproductive cycles. Indeed, all the basic phenomena investigated by both psychology and social science have already been explained in tracing the course of evolution by reproductive causation. What follows here is just a reminder of their relevance.

Psychology. In the first instance, psychology is based on our ordinary way of understanding human beings. That is to explain individual behavior and beliefs by the reason which are responsible for it, or what I have been calling “rational explanation.” For decades now, it has been is called “folk psychology” in epistemological philosophy of science, because it is generally assumed that such explanations depend on learning the relevant “laws of nature” as a normal part of the process of growing up in human society. But it has been explained here as subjectivistic understanding.

Subjectivistic understanding is part of the cognitive capacity I have been calling “reason,” for it is the use of rational imagination to think about the causes of beliefs and behavior in subjective animals like us. Reason has been explained here as a capacity that derives from the use of psychological sentences, for that is what enables the subject to represent and, thus, reflect on the psychological states that are involved causally in the process by which their animal behavior guidance system. That is the basis of the subject’s capacity to use the theoretical and practical reasoning that takes place in his own brain to simulate the reasoning going on in the brains of others, and thus, it is what enables the subject to see into the minds of other subjects.

Naturalistic understanding is another part of the capacity of reason. It is the use of rational imagination to think about the causes and effects of states of objects in space, or the kind of imagination that first evolved in primitive spiritual animals, which had only the use of natural sentences (with a subject-predicate grammar). The use of natural sentences gives the subject the concept of a state of affairs (or event) in nature, and since reason uses a faculty of imagination that is built on the spatio-temporal imagination of mammals and the structuro-temporal imagination of primates, it involves the ability to understand efficient causes and their effects (both those that depend on these basic aspects of the spatial structure of the world and those that are learned from experience of other regularities in the natural world).

Hermeneutics. By “hermeneutics,” I mean the belief that the best that science can do in the way of explaining individual beliefs and behavior is to give rational explanations.

This view is now most commonly defended in the philosophy of social science. There seems to be no hope explaining social phenomena unless the beliefs and behavior of individual can be explained. Even the gathering of statistics about individuals, as in economics and sociology, depends on being able to start with the ordinary explanations of their beliefs and behavior. Thus, those who are eager to have the social sciences recognized as a form of genuine knowledge about the world seem forced to accept a hermeneutical understanding of individual behavior.

Hermeneutics is also the foundation of most social psychology and clinical psychology for the same reason. But in psychology, there are attempts to give a deeper explanation of individual behavior, which would make it clear that psychology is a branch of natural science and, thus, no less entitled to claim that its conclusions are science. They will be considered next.

The main problem with simply accepting rational explanations as scientific explanations is that the empirical method does not lead to general agreement about what is true, at least not in a way that is comparable to using the empirical method with efficient-cause explanations.

This problem with the empirical method was discussed when the empirical method was introduced (in Method). The empirical method is the attempt to discover what is true by inferring to the best explanation of what is observable in the natural world, and as we noted, it is a method that can, in principle, be used in conjunction with various kinds of explanation: efficient-cause explanations, rational-cause explanations and ontological-cause explanations. The way that it leads to agreement in the case of efficient-cause explanations has made natural science a spectacular success in the attempt to discover the true. Its use in conjunction with ontological-cause explanations is the foundation of ontological philosophy, where it may also lead to general agreement, this time about the basic substance constituting the natural world. But in the case of rational-cause explanations, it fails to lead to agreement about what is true. Different rational subjects trying to explain the same behavior (or the same beliefs) of some individual often wind up with different conclusions, and no matter how much they consider one another’s rational explanations, there does not seem to be any way for them to reach agreement.

The problem about reaching agreement on rational-cause explanations is sometimes called the hermeneutical circle, because the attempt to resolve disputes about what an individual intends or believes in a particular case depends inferring to the best rational cause explanation. Since one standard of the best explanation is explaining the widest range of phenomena, the widest range in this case is the range of the individual’s behavior. But for other instances of the individual’s behavior to be relevant in judging which explanation is best, they must also be explained rationally, and thus, the same problem arises about explaining them. The rational explanation of one instance of behavior depends on the rational explanation of the other, and that instance on yet another, so that in the end, all the behavior has to be interpreted. The rational explanation of the part thus depends on the rational explanation of the whole, and as it happens, even when all relevant behavior is included, there are still differences among the subjective scientists.

The reason for these disputes can be explained, as we did earlier, by the nature of rational explanation. It comes down to disagreements among the subjective scientists themselves in basic their beliefs about the world, especially their most basic and general beliefs, such as moral and religious beliefs. An inference to the best rational explanation is an inference to the fewest and simplest psychological states that will explain the widest range of behavior, but it depends on a judgment about which alternative explanation is the most coherent, that is, rational selection. And since rational explanation involves using one’s own process of practical and theoretical reasoning to simulate the reasoning of others, the judgment about which alternative set of psychological states is simplest and fewest depends on using one’s own desires and beliefs (including beliefs about what is good) as the background in which they are compared. Since that background varies from one subjective scientist to the next, subjective scientists tend to disagree about which is the best rational explanation.

Inferences to the best efficient-cause explanations are not subject to this kind of dispute, because naturalistic understanding involves only beliefs about the natural world which are ultimately based on perception. No judgments about what is good and bad, or what is meaningful, or how one feels is relevant in natural science. But they are the stuff of the subjective sciences.

Insofar as such disagreements about the best rational-cause explanation are not resolvable, it is apparent that the conclusions of subjective science are not objective. The ontological explanation of the nature of reason shows that there is a good deal of validity in rational explanations, because the animal behavior guidance systems of rational subjects do work in basically the same way. Thus, to some extent, they can be used to discover the true, though the range in which they are trustworthy may be limited to more immediate intentions is rather well defined social situations. However, rational explanations will lead to much greater agreement about the reasons behind individual behavior when ontological philosophy evolves in philosophical spiritual animals, because there will be a great deal more agreement about background beliefs and values.

However, a genuine science of individual needs more than rational explanation, because psychology must be integrated as a branch of natural science. Thus, naturalists are on the right track in attempting to reduce rational cause explanations to the kind that is used in natural science.

Naturalism. There have been various attempts to reduce rational-cause explanations to efficient-cause explanations, and as a way of showing the relevance of the ontological explanation of the nature of change to issues about causation, let me mention the main varieties here.

Behaviorism. The original attempt to turn psychology into science is behaviorism, that is, the attempt to discover a law of nature describing the regularities about individual behavior so that it would be possible, in principle, to explain particular actions by efficient causes. These first attempts tried to reduce behavior to what is now called “respondent conditioning,” exemplified by Pavlov’s dog, in which behavior that is already triggered by some stimulus is conditioned so that it comes to be triggered by another stimulus. It was followed by the theory of operant conditioning, developed mainly by B. F. Skinner. Operant conditioning is based on the law of effect. When kinds of behavior that are generated spontaneously or randomly are reinforced, they are more likely to generated again, especially under similar stimulus conditions.

Functionalism. Behaviorism has been replaced in psychology by cognitive psychology. It departs from its predecessor by recognizing that behavior is mediated by internal states, and thus, it takes the project of psychology to be to discover the internal states that are responsible. But cognitive psychology does not attempt to discover the physical properties of internal states. Instead, it attempt to discover them in terms of their causal connections to input states and output states of the organism. That leads to what is called “functionalism.”

Neurophysiology. The other thriving trend in psychology is the attempt to reduce rational explanations to neurophysiology, that is, to the states of the brain. (Though brain states may still be defined functionally, the functions are physiological functions, and thus, involve descriptions that are more closely tied to physics.)

The significance of ontological philosophy for each of these projects is implicit in what has been said in tracing the course of evolution as a global regularity caused by reproductive cycles and the wholeness of space.

Neurophysiology. The problems of neurophysiology have been addressed by this ontological explanation of the course of evolution by tracing the stages of animal evolution from somatosensory through manipulative animals to rational subjects (stages 4-9). The nervous system was explained as an animal behavior guidance system, but the biggest departure from received neurophysiology comes from the recognition of levels of neurological organization and what each contributes to the animal system of representation. That functional explanation shows how structures in the nervous system serve as a faculty of imagination, that is, a mechanism in which covert behavior calls up sequences of images from memory in the sensory input system to represent the effects of motion on the relations of objects in space, of manipulation on the geometrical structures of objects in space, the causal relations among states of objects in space, and the causal relations among psychological states.

This is a different kind of neurophysiological explanation of behavior than is expected by the current defenders of neurophysiology, such as Paul and Patricia Churchland, for they are eliminative materialists, who expect rational explanations (or “folk psychology,” as they call it) to be replaced by neurophysiology. By contrast, this explanation of how the brain works explains the validity of rational explanation by showing not only how they are valid explanations, but also by explaining how it is possible for rational subject to give such explanations of beliefs and behavior.

As a functional explanation of those structures in the brain, however, it leaves a great deal yet to be explained. Indeed, all the detailed mechanisms that are required to serve these functions remain to be explained. But those nervous mechanisms are quickly yielding to the astonishing progress of empirical neurophysiology. Since they are coming at it from opposite directions, what ontological philosophy implies and what empirical neurophysiology is disclosing should converge on a single, complete explanation of how the brain works before long.

Behaviorism. What made it possible to explain the stages of neurological organization by reproductive causation was the recognition that the faculty of imagination does not require the mechanism of embryological development (that is, the multicellular biological behavior guidance system) to provide the detailed structure of the brain. It needs to provide only the basic systems of the faculty of imagination, because its structure makes possible a contained form of reproductive causation in which the behavioral schemata behind covert behavior can evolved by reinforcement selection. That is, given that there are random variations on behavioral schemata, the learning of new ways of behaving and thinking can be explained by a memory circuit that strengthens the synapses of neurons involved in generating behavior of that kind when they are successful by genetically determined criteria (such as success in getting around in space or success in social relations mediated by linguistic behavior). Thus, the brain has a built-in structure that internalizes structures of the world, from the spatial structure of the natural world to language and the capacity for reflection.

This is an explanation of the validity of operant conditioning, at least, in mammals and beyond. The law of effect is true, on this functional explanation of the faculty of imagination, because the regularity it describes is the evolution of behavioral schemata by reinforcement selection within the mammalian brain. (The memory circuit works in a similar, but far more limited way in non-mammalian vertebrates, and thus, the learning in pigeons was limited enough to stand out in the kinds of experiments that Skinner conducted.)

But this neurophysiological explanation of operant conditioning reveals that it is not as open ended and unstructured as Skinner believed, because it is the evolution of behavior schemata that operate as various faculties of imagination (spatio-temporal, structuro-temporal, naturalistic and subjectivist imagination). That is, behind the overt operant behavior, including verbal behavior) is a covert operant that calls up sequences of images of a certain kind, and thus, from the point of view of the subject, the behavior is generated in world from an understanding of the world that sees the actual against the background of the possible.

Functionalism. The neurophysiological structures in the nervous system have been explained by the functions of various systems at a series of level of neurological organization. That is a functional explanation in the strong sense that is entailed by reproductive causation and the recognition that evolution is progressive, increasingly sophisticated ways of serving as an animal system of representation are what causes each higher level of neurological organization. And these functional explanations of the levels of neurological organization include functional explanations of various nervous structures in the brain, such as the behavior generator, the local image, the object image, and the like.

These functionally described states are not quite what cognitive psychology is looking for. In the first place, they are tied certain neurophysiological structures in the brain, and thus, internal states are no explained exclusively in terms of their causal connections to (sensory) input and (behavioral) output. Secondly, the functions that are ascribed to internal states are not merely that of representing aspects of the world, but as representing objects, representing them as being located in space, as having geometrical structures, as being efficient causes, and even as having reasons. And the functions of such states depend on them being parts of a faculty of imagination.

This departure from received functionalism in psychology solves the problems that have been encountered, and by considering them more closely, those who are interested can see how.

Intentionality. The philosophical problems about the nature of mind arise from certain aspects that seem to be incapable of explanation by the basic laws of physics. One of those problems is consciousness, or the subjective aspect of experience, such as the phenomena appearance of the natural world in perception. The foundations for the ontological explanation of consciousness were discovered in Properties, and the way in which it explains the unity of mind, or the fact that many qualia appear to the subject at the same time, was explained as part of the discussion of the mammalian brain (Stage 6). The other main problem, which will be discussed here, has to do with intentionality.cxv

The problem about intentionality is how there can be psychological states that are about the world. We know there are psychological states about the world, because they are what we use to give rational explanations of behavior (and beliefs) of rational subjects (and other subjective animals). Though the mind obviously depends in some way on the nature of the brain, it does not seem that that the aboutness of psychological states can be explained by the basic laws of physics. Functionalists believe, however, that they can be explained as functional states. No one denies that it is plausible to suppose that the intentionality of psychological states involves a system of representation built into the brain. But how can states of the brain be representations? How can they be about the world?

Intentionality cannot be explained as something we read into the phenomena, as if it were just a useful way of describing or summing up what happens in nature.cxvi That would be to deny the reality of the phenomenon, at least as part of the natural world. And it is hard to see how even that is possible without contradicting oneself, because no one who holds that we are reading things into nature (or describing them in certain ways) can deny there are intentional states in the world. Those very interpretations are about objects in the natural world. The only way to avoid self-contradiction, therefore, is to hold that one’s own mental states are not part of the natural world, and that is, ontologically speaking, a form of mind-body dualism. It implies that there are two basically different kinds of substances in the world: natural entities without real intentional states, and beings like us, who must have them, since we do refer to other objects and ascribe intentional states to them. This is a disastrous kind of dualism, for there is no way to explain how substances whose natures differ as mind and body are related to one another as a single world. And even if there were, it would be to give up naturalism and, thus, ontological philosophy.cxvii

Though it is generally agreed among naturalists that intentionality is to be explained functionally, there is little agreement about what such a functional explanation would involve. There are two main schools of thought about the nature of "functionalist theories" of psychological states, and both would explain intentionality in terms of representations in the brain. One theory holds that the most science can do is give functional descriptions of the brain. The other holds that natural science can give functional explanations of the brain, although it is based on an analysis of functional explanations (the etiological theory) that precludes their reduction to the ontology of naturalism. A brief account of these theories will provide a sense of the obstacles that intentionality poses for a naturalistic metaphysics.

Intentional states as functional states.The still dominant view of psychological states is called "functionalism,” a philosophy of psychology inspired by the analogy between minds and computers a quarter century ago.cxviii The idea is that psychological states can be understood as internal states in a complex system whose kinds can be distinguished in terms of the causal roles those states play in mediating between input and output, much as internal states of computers explain its output in response to certain kinds of input because of how internal states are related by the program. Thus, the goal of psychology is supposed to be giving a functional description of the mind/brain, much as one would a computer, that is, by describing a system of interconnected internal states that tells how all possible inputs would affect output. Two points about functionalism of this kind should be noticed,

First, it denies the possibility of reducing functional systems to the kinds of physical processes that realize them. According to the deductive-nomological model of explanation, the reduction of one theory to another depends on establishing a necessary connection between the terms used by one theory and the terms used by the other, and functionalists deny that there is any such type-type identity between functional states and their physical realizations in the brain.cxix That is, the functional properties of a system are thought to "supervene" on its physical properties. One of the deepest convictions functionalists have is that, just as physically different kind of computers can perform the same computations, so physically different kinds of brains or brain states can realize the same psychological states. Functionalists are quick to point out that they are not denying materialism (or physicalism). They need not believe in the existence of anything but entities of the kind mentioned by the basic laws of physics. They admit that functionally defined states are identical to the physically defined states that realize them in each specific case. The agree that if a physical system of some kind realizes a functional system, then another physical system of the same (relevant) kind must also realize it. But they believe that there is only a token-token identity between functional and physical properties. They deny there is any necessary connections between the types of these tokens, because they believe that indefinitely many different kinds of physical systems can realize a functional system.

Second, the very form of functionalist psychology precludes any explanation of intentional states in terms of representations of the world. Psychological states are ordinarily classified not only by the propositional attitudes involved (that is, depending on whether they function as beliefs, desires, intentions or the like), but also according to content (or what they are about, beliefs about water, say, being different from beliefs about alcohol). Though the former kinds are plausibly explained by their casual role in mediating between input and output, the latter cannot be, for any correspondence to objects/states in the world would lie outside the functional system. The only way of distinguishing psychological states according to their content within the functional system is by differences in the representations themselves, that is, by the so-called formal aspects of the states (which are analogous to syntax, as opposed to semantics, in linguistic analysis). They have, in the jargon of this field, "narrow content,” but not "wide content.” They cannot have a content that depends on a relationship to objects/states in the rest of the world, because the only relationship of the system's internal states to the rest of the world is by way of its input and output, and functional theories abstract from how input and output connect to the rest of the world. Thus, since functionalist theory cannot connect the mind with real objects/states in the world, it cannot explain the intentionality of psychological states — that is, explain how and why they are about the world. It cannot, for example, say which beliefs are true. It cannot even explain what makes true beliefs true.

The leading proponent of functionalism, Jerry Fodor, argues that these two points are connected. He argues that psychology cannot explain psychological states by how physical states correspond to objects/states in the rest of the world, because functionally described states supervene on physically described states and the physical states on which they supervene are in the brain. This doctrine he calls "individualism.”cxx

Fodor does not, of course, deny that the internal states of functional systems do sometimes refer to objects/states in the world. But he proposes to account for the "wide-content" of our ordinary psychological explanations by supplementing his functionalist theory of mind with a "causal theory of reference.” The referents would be picked out as certain more or less remote causes of input to the functional system that are regularly related to the internal states. That is supposed to account for the intentionality of psychological states, but even Fodor recognizes that such a causal theory of reference has trouble accounting for some kinds of references.cxxi And there are more basic philosophical objections to such a theory, which Fodor does not acknowledge.cxxii However, neither class of problems is relevant here.

For our purposes, the problem is that, if the intentional content of psychological states can be explained only by tacking a causal theory of reference onto a functionalist theory, then far from explaining intentional states in terms of the ontology of naturalism, functionalist psychology actually makes intentionality more puzzling. Even if all the references we take psychological states to be making did turn out to have causal relations to the world, it would show, at most, that there is an objective regularity about our ascriptions of references to psychological states. But it would not explain why psychological states are about the world. need to tack a causal theory of reference onto a functionalist theory of mind would still suggest that the intentionality of psychological states is something accidental.

What Fodor’s functionalism is leaving out can be seen with the help of our ontological explanation of the function of the animal behavior guidance system. Because animals acquire their free energy by ingesting other objects in space, they need, in addition to their biological behavior guidance system, a system to guide behavior that acts on other objects in space. Thus, animal behavior is different from biological behavior, because it must direct behavior at other objects in space, rather than just at the world as a whole (or merely oriented in a gravitational or electromagnetic field). Thus, what makes animal behavior guidance systems more powerful is the evolution of a subsystem, the animal system of representation, which uses an interaction between sensory input and behavioral output to represent the objects toward which its behavior is directed.

Behavior is generated by the structure of the organism as an irreversible structural global regularity, but as animal behavior, it can make events occur regularly in its territory that are otherwise quite improbable only by acting other objects in the region. That is, what coincides with the geometrical structures of region’s thermodynamics flow of matter toward evenly distributed heat to do work is not an unchanging material structure, like a region-wide machine, but rather animal behavior, that is, behavior in which, typically, the animal moves around in the region and acts on other objects (as in chasing prey and ingesting them). But that requires animal behavior to be guided in relation to objects in space, and thus, a system evolves in the animal behavior guidance system to represent the object, or what we have called the animal system of representation. The animal stages of evolution are all increases in animal power that comes from the animal system of representation representing the nature of the world in which its behavior must act more completely.

The animal system of representation evolves first in telesensory animals. (The somatosensory animal has only an implicit representation of the object, because it uses the location of the sensory input in the body to locate the object for purposes of directing behavior at it, for example, as the hydra’s tentacles sting prey that touch it and contract to draw the prey into its gastrovascular cavity.) Embryological development constructs a nervous system in telesensory animals that uses the regular changes in sensory input as a function of behavioral output to represent the object in such a way that it can guide locomotion in relation to the object. The function of this brain structure depends on how the animal interact with other objects in space, and that is the basis of the relationship of representation between the states of the animal system of representation and the objects in space.

Functionalism abstracts from this functional explanation. To insist that such internal states be defined strictly in terms of the internal causal relations by which they mediate between sensory input and behavioral output is to cut off from consideration all the structural effects outside the body that are involved in doing the non-reproductive work of controlling relevant conditions. The culprit here is the computer analogy, and there are two ways in which it cuts psychological states off from any deeper explanation.

First, on the computer model, the only context that is relevant in a functional system is the input to the system and its output, and thus, functionalism abstracts from the part of the structural effects outside the organism. That cuts the animal behavior guidance system off from any coincidence with the thermodynamic flow outside the organism, including any relevant conditions the behavior it is generating might be controlling.cxxiii

Second, on the computer model, the internal states of a functional system are defined only in terms of the causal relations among them that are responsible for mediating between input and output, and thus, functionalism also abstracts from the structural global regularities that occur within the animal behavior guidance system. When functionalists abstract from the "physical realization" of the functional system, they are abstracting from the material structures that channel the flow of free energy in the animal behavior guidance system.

This abstraction is necessary, functionalists would insist, because there are different kinds of structural causes that could generate the same kind of structured thermodynamic order. That may be true of computers, but it is not true of biological mechanisms, because in products of reproductive causation, there is a necessary connection between functions and traits. The kind of structural effects that serve any function are determined by that function, because they are the most powerful way of controlling that relevant condition that is possible for organisms of their kind when they evolved. That necessary connection makes a type-type reduction to naturalist ontology possible.

Both kinds of abstraction are appropriate for computers, because their input and output is strictly linguistic (or digital), and many different machines can be built that manipulate the syntax of linguistic or mathematical representations. But animal behavior guidance systems are structural causes that have evolved by reproductive causation to guide behavior in a world of objects in space, not just syntax manipulators designed by human ingenuity to work in a linguistic environment. Given our definition of "functions,” therefore, neither kind of abstraction — neither from the objects in space outside the brain nor from the physical nature of the brain itself — is appropriate.

Functional explanations of intentional states. This brings us to the other received theory of the intentional content of psychological states, the one that would explain representations by their function, rather than just describe them by their causal roles as internal states in a functionalist system.

Ruth Millikan (1989, p 282) rightly challenges Fodor's assumption that the status of an inner state "as a representation is determined by the functional organization of the part of the system that uses it,” pointing out that there is no such a thing "as behaving as a representation without behaving like a representation of anything in particular.” The relationship to objects/states in the world is essential, she insists, to any explanation of intentional states in terms of representations. She is also correct to insist that such a system can be explained functionally, and not merely described functionally. But her theory fails to reduce psychological states to naturalist ontology, because she accepts a theory of functional explanations, the "etiological theory,” that takes accidentalism for granted. And as a result, she overlooks an essential ingredient in any adequate explanation of the nature of psychological states.

Let us call Millikan's kind of explanation the "teleological theory" of representations. It holds that what makes an inner state a representation is that its function is to represent.cxxiv According to the etiological analysis, representations are states of an organism that correspond to certain objects/states of the world and that were selected to be parts of the organism because they correspond to those objects/states in the world. That makes the correspondence part of the explanation of the intentional state something more than what happens to be true of it or what we read into it, because the state's correspondence to the world is responsible for the organism having been able to do something that was (and perhaps still is) required for its success in reproduction.

There are, for example, bacteria that use tiny magnets (magnetosomes) to guide their locomotion. What they represent is not, however, the direction of magnetic north, which causes their orientation, but rather the direction of oxygen-free water, because magnetosomes were selected for their correspondence to oxygen-poor water. That correspondence causes their reproductive success by enabling them to avoid the toxic, oxygen-rich water near the surface, and thus, the magnetosomes have the function of representing oxygen free water.cxxv

The teleological theory of psychological states is closer than Fodor's functionalism to the explanation entailed by this ontological explanation of the course of evolution, because instead of tacking a causal theory of reference onto a functional system, it gives a functional explanation of the correspondence between inner representations and objects/states in the world. But the teleological theory of representations nevertheless agrees, in effect, with the other abstraction involved in functionalism, for it still assumes that there is no necessary connection between intentional states and the physical states that realize them. The accidentalist assumptions of the contemporary Darwinist explanation of about the course of evolution lead to the etiological analysis of functional explanations, and since that precludes explaining course of evolution by the functions that are possible, it does not seem possible to explaining psychological states ontologically. Both assumptions of accidentalism are relevant.

First, though inner states of an animal may have the function of representing something, what they represent is contingent. Since natural selection is imposed by changes in the environment, what inner states correspond to depends on environmental changes or conditions that could be different. There may be a historical explanation of the natural selection of intentional states, but since what is represented is contingent, no ontological reduction of psychological states is possible.

Furthermore, even if the selection pressure responsible for psychological states were given and the nature of the correspondence were determined, psychological states would still not be reducible to the ontology of naturalism, because the etiological theory has nothing to say about the mechanisms that would serve that function. The kinds of inner states and how they are made to have the required correspondence would depend on which random variations happened to be available at the time the selection pressure was imposed. Thus, the teleological theory of representations does not offer an account of intentionality that reduces psychological states to the ontology of naturalism.

The examples used to illustrate states with representational functions, such as the magnetosomes in bacteria mentioned above, seem to confirm accidentalism. Though they might guide some bacteria to oxygen free water, they might guide other animals in seasonal migrations. But such examples are misleading, because they implicitly assume that the representational functions of inner states are tied directly to the control of rather specific conditions. And this may be true in somatosensory animals and simpler animals, since they do not have animal systems of representation. And since the accidentalists assumptions of contemporary Darwinism keep teleological theorists from trying to trace the course of evolution, they do not notice that the evolution of greater power in higher animals comes from serving a more universal function in behavior guidance, namely, the representation of objects for the purpose of adapting behavior to the spatial aspects of the world. That is, they overlook the inevitability of the evolution of the animal system of representation in multicellular animals.cxxvi

The animal system of representation has a necessary neurological structure in telesensory animals because of how behavioral output must be combined with sensory input to locate objects in space for purposes of guiding behavior. There are, of course, different ways of serving this function, as we have seen, with the greatest differences arising from the fundamental difference between proterostome and deuterostome embryological development. But the inevitability of the neurological structure of the system for representing the objects of animal behavior at later stages of evolution, because they use higher levels of neurological organization to represent additional aspects of the spatial structure of the world. Spatio-temporal and structuro-temporal imagination give the animal subject internal states that correspond to the world in a way that does not depend on the selection pressure that happen to have been imposed on the animal. It evolves because evolution is progressive. In order for animal to have more power to control relevant conditions, their behavior guidance systems must have animal systems of representation that represent objects as being located in space and as having geometrical structures.

These forms of imagination in animals are the foundation, as we have seen, for the evolution of naturalistic and subjectivistic imagination in primates with the use of language. But those forms of imagination are also inevitable, and they involve a correspondence between brain states and the states in the world, including other subjects, that is also necessary.

This solves a problem that functionalist explanations encounter when they try to explain correspondence with nothing but causal connections between input and output within the organism. The correspondence is not just a constant conjunction between telesensory input and the object in space that is involved in reference, as Fodor seems to mean by calling it a casual connection, but an isomorphism between geometrical structures in the brain and the geometrical structures of the locations of objects in the space around the telesensory animal.

Social science.The social sciences present yet another problem about the nature of the causal connections involved in scientific explanations. By “social sciences,” I mean the various branches of science that attempt to understand human society, from anthropology and sociology, which both claim to be the most basic social science, to economics, political science and even history, though the latter has reservations about calling itself a science at all. The main issue about the nature of causation in these fields has to do with whether explanations of social phenomena are reducible to explanations of the individuals involved in social phenomena. It is basically a dispute between individualism and holism, and what is at issue is the essential nature of the object being studied by these sciences. Whereas holism is the belief that a human society as a whole is something more than the sum of its parts, individualism is the belief that it is just all the individuals that make up society.

Individualism. The roots of individualism go back to Thomas Hobbes and Adam Smith. Max Weber stands out as a defender of individualism among advocates of hermeneutical (or interpretive) social science. But in the contemporary era, its main defenders have been F. A. von Hayek and Karl Popper.cxxvii These philosophers call themselves "methodological" individualists, because they think of individualism as principle about how to practice social science. But it presupposes an ontological position, because a science that follows that methodological principle could not be expected to discover the truth, unless the society were nothing but the behavior and interaction of all its members in the natural world.

Methodological individualist hold that all social phenomena can be explained, in principle, as either the intended or unintended consequences of the (mostly) rationally explicable behavior of the individuals involved in the situations they face. Methodological individualism does not have to take a stand on whether or not such rational explanations can be reduced to explanations in natural science. Its main point is that what makes social phenomena seem to be something more than what the individuals do is that the consequences of all their actions as they add up in space over time are largely unintended.

More recently, a form of individualism has been defended by sociobiologists, at least, implicitly. They attempt to give an evolutionary explanation of the social nature of human beings. Darwin was the first naturalist to defend an evolutionary explanation of human beings was (in his Descent of Man). But he was not an individualist, because he recognized the role of group level selection in human evolution, as well as individual level natural selection. The most recent attempts to establish a science of human society as a branch of evolutionary biology are due to Edward O. Wilson (1975, Ch. 27; 1978; and, with Charles J. Lumsden, 1983). They are individualists, because their project is to explain social phenomena by natural selection working on the individual level.

Holism. Contemporary defenders of holism about society believe that there are irreducible laws about social phenomena. Prominent epistemological philosophers of social science, such as Bhaskar (1979) and Manicas (1987), believe that casual processes throughout nature are stratified. They hold that there are irreducible laws not only at the social level, but also at other levels of organization, such as psychology, physiology, biology, and chemistry. They believe that theories in social science must mention unobservable theoretical entities, such as social structure, and as scientific realists, they believe that those entities exist in some way that is not reducible to the individuals and their behavior.

The roots of social holism can be traced to theorists about human society in the 19th Century. Among those classical defenders of holism, there is a difference between those who took a basically hermeneutical or interpretative approach to explaining individual behavior and those who were naturalists about the explanation of individual behavior (or psychology).

The interpretationalists are represented by Herder and Hegel. Herder used the notion of Das Volk as a way of pointing to the cultural aspect of spiritual animals, but he thought of culture as expressing the nature of society as an irreducible spiritual entity. Thinking of himself as the founder of history, Herder saw human history as the story of the transit though the natural world of a kind of spiritual being whose nature could be understood only from the inside (that is, through its culture). For Hegel, Das Volk became Die Volksgeist, and ultimately the state, as part of his idealist metaphysics. Hegel saw evolution and history as a dialectical progress of the Idea in which it becomes aware of itself in the natural world, and objective spirit was a later moment in that process.

The naturalists who defended holism in the 19th Century accepted the empirical method of science as the only valid way of acquiring knowledge about the world, and thus, they understood holism in terms of the social aspect of spiritual animals, rather than the cultural aspect. They rejected individualism in favor of believing in the existence of irreducible laws and/or entities on the social level. August Comte, for example, thought of science as seeking to discover basic laws of nature on each of several levels of phenomena, including physiological explanations of individuals and laws of social development. Though each branch of science went through a predicable series of stages before it discovered the basic laws (religious, metaphysical and positivist stages), the laws of higher level strata of nature could not be explained in terms of the laws of lower level strata. Emile Durkheim also thought of himself as a naturalist, but his theories turned on the recognition of a conscience collective, which seems to his detractors, at least, as belief in a group mind, though it was probably only a way of talking about the effect of the society, by way of its culture, on the members.

The ontological critique of epistemological philosophy of social science will show that individualism and holism are both true and both false. Both are true, because social phenomena are the result of organisms evolving at both the individual and social levels of biological organization at once. And both are false, because each takes the truth of what it is defending to deny the truth of what the other side is defending. Because neither side in this dispute understands the basic nature of the object investigated by the social sciences, each is describing only an aspect of this phenomenon and trying to parlay it into an explanation of the basic nature of society.

The nature of social phenomena has been explained by tracing the course of evolution by reproductive causation from primates (manipulative animals, at stage 7) through primitive and rational spiritual animals (stages 8 and 9) to philosophical spiritual animals (at stage 10, including the individualism-holism dispute). Since evolution is explained as a global regularity, everything that evolves is reduced ontologically to space and matter in a world like ours, including spiritual animals. But that does not make the levels of biological organization any less real. We have seen how levels of part-whole complexity are responsible for stages of evolution. But the three stages at which spiritual animals evolve are unique, because on them, reproductive causation is a work on two levels of biological organization at once. There are, in other words, organisms on both the individual and the social levels of biological organization imposing natural selection on themselves by their own reproduction in space. Thus, at the same time that spiritual animals are changing gradually in the direction of natural perfection for organisms subject to the condition of being made up of language-using multicellular animals as parts, the individuals are changing in the direction of natural perfection for multicellular animals subject to the condition of being parts of spiritual animals.

Since this ontological theory about the essential nature of the object of the social sciences has already been explained, I will invoke it here it to sketch the ontological critique of individualism and holism in social science.

Ontological critique of methodological individualism. What is true about methodological individualism is that the behavior of the members of spiritual animals can be explained rationally in the situations that they face. There are no effects or influences of the spiritual animal on its members that are not mediated by the rationally explicable behavior and interaction of the individuals. That means that there are no group minds nor irreducible spiritual substances that act on rational subjects by means that they cannot observe and explain. But that does not mean that social holism if false, because by means of such transparent processes, the society as a whole has decisive effects on the individuals.

The rational nature of the individuals. The most basic effect of the social level on the individuals is one that lies mainly in the past, namely, the evolution of the spiritual animals of which they are parts. It is the evolution of spiritual animals by group level natural selection through warfare that has made the individuals rational, for that is what explains the evolution of psychological sentences, which enables them to reflect on their psychological states as reasons (that is, as causes of their beliefs and behavior that are represented as such causes as an essential part of the mechanism by which they cause beliefs and behavior).

Methodological individualism takes the rationality of the individuals for granted and tries to explain the society, including their economic cooperation in civil society as well as government, as the result of rational individuals acting in their individual self interest. At one extreme, methodological individualists such as Hobbes explain society itself as a contract among rational subjects. At the other extreme, they admit that the historical origin of economic and political institutions is basically the accumulation of the unintended consequences of the rationally explicable behavior of many individuals over many generations, and so they recommend a conservative attitude about tampering with what has come to exist. But in either case, the basic premise of their explanation — that individuals are rational subjects — is simply taken for granted, and that is to ignore the most basic effect of the social level organism on the individuals, namely, the evolution of spiritual animals at the social level of biological organization by imposing natural selection on themselves through warfare.

Thus, methodological individualism fails to recognize the basic way in which holism is true: Society is not a construct of reason, but rather, reason is an effect of the evolution of spiritual animals. Reason does make it possible for individuals to act together in pursuit of common goals. But the individuals have such a power only because they already pursued common goals before reason evolved, that is, at the primitive stage, when they had only the use of natural sentences and social level behavior depended on a leader to assign tasks to individuals. Furthermore, contracts are just one way in which rational beings are able to act jointly in pursuit of common goals. Institutions themselves are ways of generating social level behavior for the control of relevant conditions on the social level that usually do not depend on contract.

Sociobiology defends a more radical kind of individualism, because it does not recognize much of a role, if any, for reason in guiding behavior. Instead, it proposes to explain individual behavior by the evolution of genes in individuals that disposes them to pursue certain goals, including to learn certain rules (or “epigenetic rules,” as Wilson calls them).

Their best example of such genes are attitudes toward incest, such as the way in which children raised together tend not to find one another sexually attractive at puberty. But sociobiologists suggest that there are similar genes for warfare, religion, male domination of women, as well as the disposition to learn certain skills and rules. And the cooperation among individuals is explained as a result of the evolution of altruistic genes as a result of what they call “kin selection.” Wilson (1975, pp. 563-564), for example, insists that ethics “reduces” to inherited emotions, and he betrays little doubt about his denail of a universal moral standard.

Though sociobiology is on the right track in looking for an evolutionary explanation of human society, their project is crippled by the accidentalism of contemporary Darwinism and its failure to recognize that levels of part-whole complexity in evolving organisms cause stages of evolution. The basic defects are its inability to explain why the evolution of language is inevitable and its failure to recognize the role of reason comes to play in guiding their behavior. Thus, sociobiology is rightly dismissed as “reductionism” in the pejorative sense, of debunking belief in the phenomena to be explained by arguing that what seems to be irreducible is not real in the first place.

The inadequacy of sociobiology’s way of explaining evolution can been seen in its attempt to reduce cultural evolution to biological evolution. Sociobiologists take human culture to be continuous with primate culture, and they explain both the diversity of cultures and why culture can change so much more quickly than biological evolution by the increased reliance on rule-governed behavior. That change is supposed to have given humans more power to change their environment than other animals. But Wilson (1975, p. 574) explains the rapidity of the “social evolution” that has given humans this power by postulating a “motor” that responds “more to internal reorganization” in society and “less on direct responses to features in the surrounding environment.” When challenged to explain what he means, he and Lumsden (1983) offered their theory of “gene-culture co-evolution,” in which culture is not only shaped by genes, but the culture that develops from those “epigenetic rules” also imposes a natural selection on genes. The rapid change is apparently supposed to come from a positive feedback between genes and culture. But if that is all there is to it, there is nothing to guide the co-evolution in one direction rather than another. Hence, it would be surprising if it made humans more powerful. The theory of gene-culture co-evolution is the accidentalist theory of evolution taken to the extreme, for the direction of evolutionary change, having been freed even of having to track changes in an external environment, can take off in any direction. It apparently just happened to take off in the direction of technological control.

The rationality of the individuals is an effect of the social level on the parts in the long past, however, and so we can set aside those earlier stages in human evolution and assume, as methodological individualists do, that the individual are rational. But even when we start with individuals as rational subjects, there are other ways in which the spiritual animal affects its members that also go unrecognized by methodological individualism.

Cultural evolution. One way in which the social level organism affects the individuals as rational subjects is by way of cultural evolution. The individual internalizes the culture of his spiritual animal as a normal part of his development after birth, including not only the language and the capacity to generate arguments (that is, the evolution of behavioral schemata in rational imagination), but also the arguments and conclusions that have accumulated as the culture (that is, all the belief based on the mammalian map of its territory as a way of representing the whole world, including rational subjects who have bodies). That indebtedness to earlier generations is recognized, of course, by methodological individualists, but what they do not see so clearly is that the exchange of arguments, including the education of new members into the culture, is a form of evolution by reproductive causation that has been contained within the spiritual animal for many generations.

Individualists tend to assume that contributions to culture come from individual geniuses who bestow their insights on the rest of us. But that is merely to focus on the random variations rather than the natural selection. The random variations that can be tried out depend on the point that has been reached in the gradual evolutionary change toward natural perfection at any stage, for it is just a recombination of already evolved structures, and thus, it is inevitable in a large enough population, if it is possible at all. But it becomes part of the culture only because others judge that accepting such arguments gives them a more coherent world view, often including a more coherent set of general intentions (or values). That is, the culture evolves by the rational selection of arguments by the individual rational subjects in the spiritual animal, and that is a social level process.

Cultural evolution is an effect of the social level on the individual, because it is a change that depends on the spiritual animal also having a social aspect. The social aspect is a structure of the spiritual animal as a whole, the aspect that has to do with how the members are related and interact as objects in space. At a minimum, they are in continual linguistic interaction, and in rational spiritual animals, that means that arguments are evolving by rational selection. But the culture is also an aspect of the spiritual animal. Though culture is potentially complete in each individual brain (when it has mastery of all the arguments that have accumulated), the culture is a structure of the spiritual animal as a whole, because it also exists in the brains of all the other members and it is exchanged by linguistic interactions.

The social whole has, therefore, an effect on the part, because the continual linguistic interaction among members of a rational spiritual animal is a contained form of reproductive causation in which culture evolves in the direction of discovering the true, the good and the beautiful. But methodological individualists have no need to deny this kind of holism, because it does not compromise the autonomy of the individual. Cultural evolution does not require anything to be true of the social whole that cannot be explained individualistically except the basic fact that the rational individuals are in continual linguistic interaction as parts of a spiritual animal (and we have seen how that is explained by reproductive causation).

The invisible hand.Methodological individualists point to the market as their prime example of how the rationally explicable behavior of many individuals in the situations they face has consequences that none of them may intend. But even this phenomenon depends on a kind of holism that they do not recognize.

Adam Smith is an individualist hero because he showed how the tendency to “truck and barter” leads to a division of labor which makes the production of goods more efficient. Though each individual is pursuing his own self interest, the result of their market interactions is an economic system from which they all benefit. That is the prime example of the “invisible hand” at work

What methodological individualism overlooks, however, is how the market system is a form of class structure, that is, a later stage in the evolution of the social aspect of spiritual animals. As we have seen, there is an inevitable series of stages of social evolution, from nomadic bands through agricultural villages to civilized societies, which are based on a class structure, such as feudalism or slavery. Agriculture introduces the institution of the private ownership of land and other property. Class structure evolves because random variations in the institution of property that give one group of members power over another make it possible to coordinate the behavior of many more members, and since the increased population gives civilized societies an advantage in war, they tend to be naturally selected. It is possible for capitalism to evolve from feudalism in philosophical spiritual animal, because as we has seen, they have a culture that expects rules of morality and justice to be justified on basic principle that recognize the rational autonomy of individuals and they can have a natural science that can develop techniques for controlling what happens by using mathematics to see beneath the observable surface of physical processes.

Capitalism involves, as we have seen, a class relation. There is a basic difference between the role of the capitalist and the worker in the process of production. The worker sells his labor power on the market for a wage, while the capitalist buys labor power and other capital goods to produce commodities for sale on the market and takes the profit. To be sure, it is a class relation that is quite different from feudalism, because the social roles are not necessarily inherited. Besides mobility between the classes, it is possible for the capitalist class relation to evolve into a more abstract form, in which everyone, or nearly everyone, plays both roles, as capitalist and worker. But the class structure is still essential, because it is the mechanism that puts some members in a position of power over other members so that the behavior of many individual can be coordinated to carry out the productive activity of the spiritual animal. .

Methodological individualism does not recognize class structure as a basic trait of spiritual animals. They see only the individuals, each owning different kinds of property, exchanging them on the market. But that is just how the institution of property is used to sustain the class relation in a capitalist society. There must be some members, at least, with sufficient money to start up processes of production, and there must be other members who are willing to sell their labor power for a wage. Historically, these roles come from individual owning different quantities of property, and that is sufficient to serve the function of a class structure.

The work of the invisible hand.A consequence of failing to recognize that the invisible hand of the market is actually a form of the class relation by which large civilized societies are possible is that methodological individualists also fail to recognize its long term effect. Adam Smith argued that market exchanges make production more efficient by leading to a division of labor. But the more important effect of the market in the long run is the way in which capitalism is a contained form of evolution by reproductive causation.

We have seen how the competition among capitalists for a profit involves capitalist selection. What evolves are the processes of production. They reproduce in time as capitalists reinvest in them for another period, and they reproduce in space as well when capitalists invest in new processes of production. But there is a limit on the processes of production that can go through such reproductive cycles, because the commodities must be sold on a finite market, and those producers that offer better commodities at lower prices are the ones who succeed in selling their commodities and, thus, make a profit. It is not just chance which processes of production continue to go through reproductive cycles, because capitalists prefer to make a profit, and they will invest only in production processes that do. Thus, the efficient production of commodities is the non-reproductive work, and since reproduction is by investment in production processes, there is gradual evolution by capitalist selection. There is change gradually in the direction of natural perfection for production processes of their kind, that is, in which commodities are produced as efficiently as possible -- or as Marxians would say, with the least labor time.

As in biological evolution, however, there is also a change at the ecological level. As reproducing organisms (production processes) are changing in the direction of increasing power to control all the conditions that affect their reproduction, the organisms in the region of space tend to diversity to tap all the sources of free energy (to supply all the commodities that people will buy at the price that they must charge to make an average profit). Thus, although production processes start out simple, uniform and not very efficient, they gradually become more complex, more diverse and more efficient. The increase in diversity means that technology, made possible by natural science, is continually being used not only to make the same products more efficiently, but also to produce new and better commodities.

Capitalist evolution is an form of reproductive causation that is contained within spiritual animals, and thus, it is a social level process, or an effect of the spiritual animal as a whole on its members. This is the longest range unintended consequence of the “invisible hand,” but methodological individualism tends to overlook it, because they think of the efficiency as an equilibrium toward which the market economy tends. But far from being an equilibrium, it is an evolutionary process, with the same creative powers of biological evolution.

Methodological individualism is basically correct in its insistence that nothing happens in social processes except the rationally guided behavior and interaction of the members. But its failure to recognize how reproductive causation has shaped individuals to have capacities that work together as a whole means that it overlooks ways in which such individually explicable behavior has added up, and continues to add up, in space over time to social level regularities that affect the individuals.

Ontological critique of social holism. The truth of social holism is aso, therefore, not quite what social holists have imagined.

Contemporary social holists, like Manicas and Bhaskar, who believe that there are irreducible social laws are correct in denying that social laws can be reduced to the basic laws of physics. But that irreducibility comes from not taking into account global regularities, namely, the reproductive global regularities. Reproductive causation is the source of all the ways in which ontological philosophy disagrees with methodological individualism.

The evolution of spiritual animals that makes individuals rational is by natural selection, or reproductive causation on the social level of biological organization.

The evolution of culture is by the rational selection of arguments, or a form of reproductive causation contained within spiritual animals.

The evolution of social structure, including capitalist class structure, is by natural selection of spiritual animals, or reproductive causation on the social level of biological organization.

The evolution of processes of production is by capitalist selection, or a form of reproductive causation contained within spiritual animals.

These are regularities on the social level which social science is trying to explain, and though they are not reducible to the laws of physics, they are ontologically reducible. There is no reason to believe that social laws will refer to unobservable theoretical entities that cannot be explained as being constituted by space and matter as substances enduring though time.

Ontological philosophy must, however, deny traditional forms of social holism that postulate entities that are not constituted by space and matter.

Thus, ontological philosophy must deny the existence of Hegel’s Geist and Herder’s Das Volk, if holists insist that spiritual animals be explained as by the kinds of entities whose existence is affirmed by epistemological philosophy. But the more interesting aspect of this critique is that what Hegel and Herder were referring to is spiritual animals. They portrayed spiritual animals as idealist entities, because they recognized that they have a cultural aspect. But ontological philosophy offers a more complete explanation of what they were referring to by explaining the nature of spiritual animals as a product of evolution by reproductive causation, that is, in which spiritual animals have both a social and a cultural aspect.

Ontological philosophy must deny the positivism that made Comte so confident that laws describing the behavior of societies would be irreducible. There is a deeper explanation, and it is an explanation of the metaphysical kind that Comte dismisses as the “metaphysical stage” preceding positivism in the evolution of science. It is the ontological explanation of evolution on the foundation of spatiomaterialism.

Finally, the social holism of Durkheim must also be rejected, because there is no irreducible tendency of the conscience collective to generate institutions that increase social solidarity. The social solidarity comes from the basic nature of the spiritual animal and, thus, stems from its evolution. And the functionality of the institutions of society is also explained by their capacity to sustain populations that make them better able to win at war, though it is as often mediated by the recognition of that advantage as it is by actual natural selection by warfare. There is no direct, irreducible connection between something contributing to social solidarity and what individuals are constraned to do.

What Ought To Be

The implications of spatiomaterialism are ontologically necessary truths, but there are two kinds of necessary truths. They are all ontologically necessary for reason, because ontological philosophy is an argument about the world directed toward rational beings. But in addition to its theoretical function, reason has a practical function, and since its practical function cannot be entirely reduced to its theoretical function, there are necessary truths about what ought to be, as far as reason is concerned, that are not just truths about what is.

Ontological philosophy is a two step argument. First, it argues that spatiomaterialism is the best ontological explanation of the world, and then it uses spatiomaterialism to show what must be true in a spatiomaterial world. Such implications are ontologically necessary, but many are conditional, because they also depend on space and matter having the more specific essential natures that makes the basic laws of physics true and that give the universe a large scale structure of the kind it actually has. Conditionally necessary truths hold only in spatiomaterial worlds like ours. There are, as we have seen, many such truths about what is, most relevantly at this point, including all those about progressive evolution. On suitable planets, there is an evolutionary change that proceeds through a series of stage in the direction of natural perfection, with each stage being a gradual change in the direction of the natural perfection of organisms (or primary structures) of its kind. And since it is a (conditionally) necessary truth, evolution would unfold in basically the same way in any spatiomaterial world like ours.

Reason itself is, however, something that comes to exist in that grand process. A series of inevitable stages of biological evolution (by natural selection) leads to rational beings, and since spiritual animals contain within themselves cultural evolution (by rational selection), which eventually includes progress in natural science (sponsored, in part, by economic evolution through capitalist selection), reason eventually comes to understand how the world is whole. That is, as we have seen, what ontological philosophy contributes to cultural evolution at the philosophical stage in the wake of the failure of epistemological philosophy. Ontological philosophy is an argument about the wholeness of the world that is made to beings that exist necessarily in that world. Thus, rational beings eventually come to recognize their own nature and their place in the world, and since that self-understanding is itself part of the wholeness of the world, it plays a role in what happens in the world. “Ontological reason,” as I will call it, has work to do.

What reason comes to know about its nature, with the evolution of ontological philosophy, includes recognizing its own function as a behavior guidance system. Guiding behavior is the basic function of what evolves at every stage of biological evolution, and reason guides the behavior not only of individual subjects, but also of spiritual animals, the social level animals of which rational subjects are the parts. Its function as a behavior guidance system explains, as have seen, the difference between theoretical and practical reason.

Practical reason is as basic as theoretical reason. Indeed, the original function of arguments about the true is to enable reason to discover the good. Reason would not have evolved by natural selection if the cultural evolution of theoretical arguments by rational selection did not make it possible for reason to discover what is good for rational beings (that is, what contributes to their maximum holistic power, or natural perfection). Thus, in addition to its theoretical role, reason has a practical employment. Reason is something that acts in the world. That is why there is a difference between conclusions about what is and what ought to be among the necessary truths proved by ontological philosophy.

With the evolution of ontological philosophy, therefore, reason understands its own nature as a behavior guidance system that evolves by reproductive causation, and it recognizes its place in the world. The function of reason is to guide the behavior of the most powerful organisms that come to exist in evolution, and so ontological reason comes to recognize itself as the most powerful being in the world. This self-understanding might even be called the outcome of evolution in a spatiomaterial world like ours, at least, so far, since it happens at the end of a series of inevitable evolutionary stages. But the advent of ontological philosophy is not the end of evolution. Its explanation of the wholeness of the world is merely the point at which reason discovers its own real nature and begins to assume its full power. And since reason has a practical, as well as a theoretical, function, it can be described as the point at which ontological reason (still evolving by rational selection) takes over from biological evolution and controls the course evolution.

Thus, the wholeness of the world is not merely that everything in the world and everything about the world is constituted by space and matter. Nor is it merely that its essential nature entails that a part of any spatiomaterial world like ours inevitably comes to understand its wholeness. It also includes how that understanding of its wholeness leads reason to act in a way that ultimately makes the world more "whole." That is the work of ontological reason.

Predicting the future of evolution. It might seem that what ontological reason does in the world ought to be counted among the necessary truths about what is, because cultural evolution, including its evolution, is a global regularity like the rest of evolution and, thus, can be predicted. As a behavior guidance system, reason pursues the good, and since goodness is contributing to natural perfection, what is good is a fact about the world. Thus, what reason does in the world can be predicted. That means that it is one of the necessary truths about what is in the world that reason discovers, which suggests that there is no need to distinguish from what is a set of necessary truths about what ought to be.

In a sense, it is true that what ontological reason does can be predicted, for it is inevitable. But it is not merely an ontologically necessary truth about what is in a spatiomaterial world like ours, because unlike earlier stages of evolution, what happens depends on ontologically necessary truths about what ought to be. That is, what makes those predictions about the future after the advent of ontological reason turn out to be true is that rational being do what is good, and so the only way to predict what will happen is to work out what ontological reason discovers about what ought to exist. That is not something that can be predicted by knowing what is good for rational beings in the sense of contributing to their natural perfection as rational beings.

After recapping the ontological explanation of the nature of goodness and considering more carefully why it seems that practical reason can be reduced to theoretical reason, I will explain why necessary truths about what ought to be are not entirely reducible to necessary truths about what is. Then I will take up the implications of spatiomaterialism about the goals that reason ought to pursue (in its individual self interest, its spiritual self interest, and its religious self interest).

Goodness. The nature of goodness is explained, as we have seen, by the progressiveness of evolution by reproductive causation. Not only does evolution have an inevitable beginning in a spatiomaterial world like ours, but it also involves change in the direction of natural perfection. And natural perfection has a structure that determines what is good.

Natural perfection. Setting reason aside for the moment, reproductive causation generates four different forms of natural perfection: the natural perfection of the organism, of the ecology, of life and of change itself. That is, they follow from the two main reproductive global regularities, gradual and revolutionary evolution.

Organism. At each stage of evolution, there are reproducing organisms (or primary structures) that start off simple, uniform and weak, and during the stage, they gradually become more complex, diverse and powerful, until each kind of organism is as powerful at controlling all the conditions that affect its reproduction as possible for primary structures of its kind. Such maximum holistic power is the natural perfection for organisms. It is an optimal part-whole relation in which no possible change in the parts will make the whole more powerful, though this maximum may be approached only asymptotically.

Ecology. But since maximum holistic power for organisms (i.e., primary structures) also involves their becoming more diverse, the direction of gradual change is also toward maximum holistic power for the ecology. It is a holistic power, because it is the power of all the organisms in the region. But the appropriate measure of the power that is maximized at the ecological level is different. As the organisms all become naturally perfect, the right kinds and varieties of organisms exist to consume as much of the available free energy to fuel reproductive cycles as possible. Making maximum use of the ultimate source of the power to do work in the region is the natural perfection for the ecology.

Life. But one stage of evolution can make another stage inevitable. When the organisms evolving at one stage have structures that can be organized as the several parts of an organism on higher levels of organization (that is, whose primary structures have higher levels of part-whole complexity), and when that makes it possible for the whole to control a range of relevant conditions that were previously out of reach, such a radical random variation begins a new stage of gradual evolution during which those organisms and the ecology they help make up (along with organisms from previous stages) become naturally perfect for their kinds. The succession of evolutionary stages uses the part-whole relation in space to expand the power of organisms, as primary structures generating reproductive cycles, to control what happens in the world, step by step, increasing the level of organization of the natural perfection involved. Hence, revolutionary evolution is in the direction of the natural perfection of life itself, or the very enterprise of controlling conditions in the world. Reproductive causation makes the most of the spatial structure of the world by using the part-whole relation in space to increase the holistic power of organisms of all kinds to control what happens in the world.

Change. Finally, since evolution is progressive, there is even a natural perfection about the kind of change that is involved in evolution. Since evolution is a global regularity caused by how reproductive cycles add up in space as time passes, each moment during each stage of gradual evolution makes a necessary contribution to the increasing power of the organisms and the ecology at that stage. And since evolutionary stages are caused by levels of part-whole complexity in evolving structures, each stage makes an necessary contribution to the increasing power of life. Thus, by using each moment in the existence of the substances involved to increase the power of material structures to do work, reproductive causation gives change itself a kind of natural perfection. It makes the most out of the temporal nature of the world by using the succession of moments in which substances exist to increase the power of organisms to control what happens in the world. No moment is redundant or superfluous.

The nature of goodness. Natural perfection is an explanation of the nature of goodness, because natural perfection is an optimal part-whole relation. Though the part-whole relation is somewhat different in each form of natural perfection, in each case, parts of certain kinds are combined in certain ways and numbers to make the most out of the least. "The most" always has to do with the power of the whole to use free energy to control what happens in the world, and "the least" has to do with the number and simplicity of the parts.

Natural perfection is a property of the whole, and the corresponding property of the parts of such wholeness is goodness. Goodness is the property of contributing to the natural perfection of the whole of which it is part. But since there are different forms of natural perfection, there are different ways that that things can be good.

Organism. In the case of the organism, the parts are the structural causes that are bundled together to go through reproductive cycles as a whole, and things are good for the organism when they are involved in generating the non-reproductive structural effects that help give it the maximum power to control the conditions that affect its reproduction. Thus, certain kinds of traits are good for the organism because of their functions, that is, because of which relevant conditions they control. And certain kinds of behavior are good for the organism because of its goals, including, in the case of animals, animal behavior, whose goals involve behavior directed at other objects in space in order to control relevant conditions.

Ecology. In the case of the ecology, the parts are the organisms in the region, and things are good for the ecology when they help the organisms jointly consume as much as possible of the free energy available in the region as fuel for reproductive cycles. Each kind of organisms is good for the ecology because of the form of free energy it taps or the way in which it does so.

Life. In the case of life, the parts are the successive levels of part-whole complexity in the reproducing organisms that evolve at each stage of evolution, and things are good for life itself because they are involved in the evolution of another level of organization that helps life control as much as possible what happens in the world. Thus, certain levels of biological, neurological and forensic organization in evolving structures are good for life because each is necessary for life to evolve another range of powers and, thus, step by step, as much power to control conditions affecting reproduction as possible for living organisms.

Change. In the case of change itself, the parts are particular stages in the overall course of evolution and particular moments during each stage, and things are good for change itself when events unfold in a way that helps bring about the natural perfection organisms, ecology and life. Thus, even such events as organisms failing to reproduce because of scarcity and species becoming extinct because other species displace them from their ecological niche are good because that is how reproductive causation makes evolution progressive.

The unity of goodness. Though things are good in various ways, ultimately, they are all good in the same way, because there is a necessary overall structure to the various kinds of natural perfection to which they all contribute. Naturally perfect organisms are essential parts of naturally perfect ecologies, and stages of gradual evolution in the direction of such natural perfection are essential to the overall evolutionary change in the direction of the natural perfection of life. And all the events that occur in the course of evolution are essential to the natural perfection of change, since that is what makes evolution progressive.

It is true that what is good for one organism might be bad for another. The predator is bad for the prey. But since the natural perfection to which they both contribute is a single spatiotemporal whole with an overall structure, there is no ultimate conflict about whether something is good or bad. Everything good is good because it contributes to some form of natural perfection that is part of that overall structure. Thus, what is bad for the prey is good not only for the predator, but also for the ecology, and it is by contributing to the natural perfection of the ecology that the prey is good (and that what contributes to the natural perfection of the prey is good). There is no context in which contributing to natural perfection, or natural perfection itself, could turn out to be bad.

The apparent reducibility of practical to theoretical reason. Since what is good is a fact about the world, or an aspect of what is, it is something that theoretical reason knows at the ontological philosophical stage, for that includes knowledge of the nature of goodness. And since reason gives rational beings the autonomy to do the good because they believe that it is good, it should be possible to predict what ontological reason will ultimately do in the world.

To know the course of evolution, it is not necessary to know all the details about how it will happen, because it is a global regularity about what happens in whole regions of space. This holds for cultural evolution by rational selection as well. It is possible to know how culture will evolve without predicting all the details. That is, after all, how we know that the evolution of ontological philosophy is inevitable.

Even before reason discovers the nature of goodness, it is sometimes able to tell what is good, because rational imagination enables rational subjects to discern what is naturally perfect. Reason can see the uniqueness of the naturally perfect, because it stands out against the background of what all is possible. Thus, reason can tell, in principle, what is good for any organism, for the ecology, and for life itself. Even in the case of individual subjects and spiritual animals, where inherited desires have the function of picking out goals to be pursued, reason judges which actions are good by their contribution to the natural perfection of the whole of which they are part. Thus, it is possible to predict what reason will wind up believing and doing.

Thus, when reason discovers how the world is whole and comes to understand its own nature and its own place in evolution, it will use its understanding of the nature of goodness to sharpen its perception of what is naturally perfect and, thereby, discover more accurately and completely what is good. Though it will still be a result of cultural evolution by rational selection, rational subjects will be better able to judge which arguments make their world view more coherent, because they will understand how everything in the world fits together as a whole and that will constrain their views on particular normative issues in ways that previously seemed impossible. The completeness of their understanding of the nature of the world is what enables reason to see which truths are necessary, including necessary truths about what is good. And since reason will recognize itself as having, in its practical employment as behavior guidance system, the function of doing what is good for rational beings, it will do whatever it discovers to be good for itself.

Thus, it seems that there is no basic difference between the implications of spatiomaterialism about what exists and what ought to exist. What ontological reason will do in the world is inevitable, like any stage of evolution, and thus, it is something that can be known by theoretical reason alone. Since practical reason does not play an essential role in explaining what reason ought to do, necessary truths about what ought to be can be reduced to necessary truths about what is.

The irreducibility of practical reason. Contrary to this impression, however, the necessary truths of practical reason about what ought to be cannot be eliminated in favor of necessary truths of theoretical reason about what is. There are two reasons, one superficial and the other more profound.

First, some of the goals that reason will pursue are optional. Reason gives subjects the capacity to do what is good because it is good, that is, simply because they believe that it is good, and as we have seen, that means that rational subjects can pursue goals in addition to those that control relevant conditions (that is, in addition to conditions that affect their own reproduction). These “optional goals” must already be good (by contributing to natural or artificial perfection in some way), but there is such a wide range of goals to choose from that it is not possible to predict which ones will be chosen. And since choosing them is what makes them good for the rational subject, it is not possible to predict all of the goals that rational beings will pursue. It is also possible for spiritual animals to pursue optional goals. Thus, the future course of evolution is, in principle, not predictable.

Optional goals for rational beings are like aspects of biological evolution that are contingent. It is not possible to predict contingent aspects of evolution, because they are not essential to the global regularity caused ontologically by reproductive cycles and space. Indeed, it is not always easy to see, even in retrospect, what is inevitable about the course of biological evolution and what is not. Since optional goals are contingent, what reason does in pursuit of them is not predicable. Thus, if optional goals are as big a part of what ontological reason does as its power would suggest, much of the future course of evolution is not predictable, at least not on ontological grounds.

The pursuit of optional goals means that what reason does in the world is more like the creation of something beautiful, like a work of art, rather than something it discovers, like a truth about the world. There will be a perfection about it, but since it is an expression of a unique form of life, it will be a unique form of beauty.

Though ontological philosophy includes everything that reason can know about the nature of the world, the future course of evolution will depend on the optional goals it chooses to pursue, and thus, reason stands to its work in the world like each rational subject stands to his or her own Self.

Insofar as the future course of evolution is not predictable, it cannot be among the necessary truths of ontological philosophy about what is, and thus, practical reason cannot be reduced to theoretical reason.

Second, there is a more profound reason why practical reason cannot be reduced to theoretical reason. That is because reasoning about what ought to be may make the pursuit of certain goals inevitable for ontological reason, even though they cannot be predicted from what is good for reason as a behavior guidance system for individuals and spiritual animals. Doing what is good for the world as a whole is such a goal, and it may be a necessary truth about what is in a spatiomaterial world like ours that they are pursued. But it is an ontologically necessary truth about what is that can be known only by reasoning about what rational beings ought to do. Thus, we cannot know whether there are any such goals without following out all the practical implications of our ontological foundation.

Goals that would be of this kind are ordinarily called “religious,” because they come from the recognition that there is something that is worthy of worship. Such a religious interest may not be reducible to the individual or spiritual interest of rational beings, because it could depend on recognizing the existence of God. And if God is not necessarily a transcendent being, naturalism does not rule out the possibility of God's existence.

Though religious goals are pursued before the evolution of ontological philosophy, that earlier pursuit of religious goals is among the necessary truths of theoretical reason (about what is), because religious goals (and the beliefs about God on which they are predicated) can be predicted, as we have seen, by the function of religion at the rational spiritual stage (that is, as the attempt to provide an ultimate justification of the principles of practical arguments, including morality and submission to the group, which are part of rational culture). But that function does not require belief in God after ontological philosophy evolves, because its ontology entails, by way of the reproductive global regularities, an explanation of the nature of goodness that explains why rational subjects ought to be moral. Moral beliefs do not depend on God for their justification.

Similarly, at the philosophical spiritual stage, religious goals pursued as a result of the belief in a transcendent God (as part of epistemological philosophy) are necessary truths of theoretical reason, because they are a predictable part of its attempt to overcome the dichotomy between theoretical and practical reason. But ontological philosophy explains the nature of reason in a way that entails that dichotomy, and thus, it does not need God to overcome the dichotomy of facts and values.

Neither belief in God nor religious goals can be predicted by theoretical reason alone after ontological philosophy evolves, because they do not help maximize the power of reason to control relevant conditions. But it is nonetheless possible that its pursuit of religious goals is inevitable, because given what ontological reason knows about the world, it may realize that there is something that is worthy of worship and, thereby, know that it ought to pursue such goals. If so, those goals would be good for reason, and the pursuit of those goals would be the work of ontological reason in the world. That is how the wholeness of the world may include how reason makes the world more "whole"it would be otherwise.

Though this conclusion of practical reason would depend on what ontological philosophy implies about what is, it would be practical reason that leads ontological reason to take up this work in the world. To show the inevitability of the pursuit of religious goals, we would have to follow practical reason to its conclusions, and so practical reason could not be reduced to theoretical reason.

That is the sense in which reason is not merely the knower of what is, but also an agent that helps determine the future course of evolution. What it does would not be not determined in the way that everything is caused prior to the evolution of ontological philosophy, but would be an act of free will. And it would be a truly creative act.

The pursuit of religious goals, if they are pursued by ontological reason, are ontologically necessary in the end, and thus, they are indeed a necessary aspect of a spatiomaterial world like ours. But the way that ontological philosophy knows them is different from all the other necessary truths, because this necessary truth cannot be known without using practical reason at the ontological stage. But once it is known by way of practical reasoning, it is also known by theoretical reason. It is part of what is as well as what ought to be. It is just that theoretical reason is essentially reflective in the end, knowing about its own role as an agent in the world. This is, as we shall see, God's knowledge of himself as a person.

In order to discover whether reason has such a religious interest, therefore, we shall consider all the goals that reason ought to pursue in three steps, by considering the three practical interests that reason has (or may have) because of the nature of the beings that are rational. The first is the individual interest, which reason has because of its responsibility for pursuing the good of the individual as such. It is usually called “self interest.” The second is the spiritual interest, which comes from reason’s responsibility for guiding the behavior of the spiritual animal. And the third is the religious interest, because that is the traditional name for the interest that reason has when it pursues in the belief that there is something that is worthy of worship, that is, something of such exalted glory that reason ought to revere it and serve it, even beyond its own individual and spiritual interest.

These are interests that reason has in addition to its interest, as reason, in knowing the good, the true and the beautiful. The latter are rational interests, which contribute to the natural perfection of culture as a result of cultural evolution by rational selection. But the interests to be discussed here are practical interests, because they have to do with how reason guides the behavior of the beings whose behavior it controls. Which goals rational beings pursue depends on what is good for them, and that makes it a matter of practical reason.

Ultimately, they are all, of course, interests of the individual rational subject, if they are interests at all, because the subject, as an individual mind, is the ultimate agent of reason in its function of guiding behavior. The individual is the being who must ultimately judge what is good, true, and beautiful and, indeed, who must ultimately do what is good. Thus, they are all forms of "self interest," where the Self is understood as the four dimensional object that one constructs by how one leads one’s life, for they are interests that rational subjects must pursue as part of such a life.

With the evolution of ontological philosophy, therefore, reason recognizes itself as the inevitable outcome of evolutionary change in a spatiomaterial world like ours. Ontological reason recognizes itself as the most powerful being in the world. And reason recognizes itself as having the function of doing what is good for rational beings. Thus, the main question for practical reason is, “What are those goals?” It can be answered by determining what contributes to the natural perfection of rational beings.

Self Interest

By “self interest” I mean, in this case, “individual self interest,” or the interest that the rational subject has as an individual.

Since in our terms, the “Self” refers to the life of the rational subject, all the practical interests of the rational subject can be can be called forms of self interest. Thus, given that the rational subject also has a spiritual and religious interest, their corresponding names would be her “spiritual self interest” and her “religious self interest,” respectively. (See discussion of these forms of self interest in Change: Dichotomies of rational level culture.)

Individual self interest includes, as we have seen, two kinds of goals, necessary goals and optional goals. The necessary goals are the goals that are good for the individual because they control conditions that affect her reproduction as an individual. Optional goals are goals that are good for the individual because they are good in some other way and the individual chooses to pursue them, making them good for herself. These two kinds of goals are good in different ways, and since there are correspondingly different reasons why they are what ought to exist as far as reason is concerned, let us consider them separately.

The individual subject is a multicellular animal, and like any animal, there are certain conditions that the rational subject must control because they affect her reproduction. These are the necessary goals of individual self interest.

They include all the goals implicit in animal nature, such as obtaining food, shelter and other necessary resources. But they also include goals implicit in the nature of the animals that are parts of spiritual animal, that is, the social goals, such as maintaining family relations, having friends, and other social relations that are normal for members of one’s spiritual animal. To a certain extent, therefore, they are relative to the technology and style of life that prevails in the spiritual animal in which one lives. However, they do not include animal goals that are incompatible with being a member of a spiritual animal, such as avoiding the risk of losing one's life fighting wars, since that is a necessary aspect of the ecological niche that individuals occupy

It should be kept in mind, however, that necessary goals do not include reproduction itself. Reproduction is not one of the conditions that affect reproduction, but, rather, what determines which conditions are relevant to control, which is the criterion for necessary goals. By controlling relevant conditions, the subject is in a position to reproduce, if she chooses. But reproduction itself is an optional goal (unless, perhaps, reproduction must be controlled because of necessary goals pursued by the spiritual animal). Reproduction is good for the subject, if she chooses to reproduce, and it brings with it all of the other goals that having children entails.

Necessary goals are normally picked out by desires that are inherited as part of biological nature, which include social goals. From hunger to the need for companionship and love, the goal selection system built into individual subjects by the biological behavior guidance system guides behavior toward goals that control conditions that are relevant in the sense of affecting individual reproduction. But what makes the goals good is not that they satisfy desire, as hedonism mistakenly assumed. Rather, as evolution by reproductive causation implies, they satisfy desires because they are good in the sense of contributing to one’s maximum holistic power as an organism, that is, of contributing to the natural perfection of the individual as an organism.

The function of the desires that motivate the pursuit of necessary goals is the same as in other animal organisms, namely, that they control some condition that must be controlled in order maximize one’s power to control relevant conditions over one’s entire reproductive cycle. In other words, they contribute to the natural perfection of the individual in the same way as the goals pursued by non-rational animals.

Even the hedonistic rational subject, before ontological philosophy evolves, is more powerful than non-rational animals, because when she chooses to behave in the current situation in ways that will maximize the satisfaction of her desires over her lifetime, she also tends to be choosing ways of behaving that control the relevant conditions more efficiently and reliably.

But when the rational subject gives up hedonism in favor of a functional explanation of desires and recognizes that the control of relevant conditions, rather than the desire, is what makes the object of desire good, she is even more powerful over her whole life than the hedonist. The desires built into the brain as part of its goal selection system are a crude indication of the kinds of goals that will give the individual the maximum holistic power of an organism. She is better able to see the relative importance of such goals and how they can be attained as efficiently as possible by considering their role in controlling relevant conditions than by the amount of pleasure they give.

Our ontological explanation of the nature of goodness implies, therefore, that necessary goals are good for the rational subject as an individual because they contribute to her natural perfection as an individual organism. And since they are good for the rational subject, we infer that the rational subject ought to pursue them. That is the form of the argument that will be used to show that goals are good for reason in each of the cases below. But it is commonly assumed that the difference between facts and values makes any such proof impossible, that is, that values cannot be reduced to facts. Indeed, there is a famous philosophical argument against this kind of explanation of what ought to exist, and it will be answered here, though it works the same way for all the goals that determine what ought to exist for reason. What is at issue is whether there is a naturalistic fallacy.

It seems that there is reason to doubt that this argument about the goals that rational subjects ought to pursue is valid. For it can be argued that, from the premise that a goal is good for a rational subject in the sense of contributing to her natural perfection as an individual organism, it does not follow that she ought to pursue it. Indeed, the belief that any such implication holds is called the “naturalistic fallacy.”

Ontological philosophy does give a naturalistic definition of “good,” because it defines “good” as contributing the natural perfection and that is a property that can be known by theoretical reason alone in explaining the nature of evolution (as reproductive global regularities). But according to G. E. Moore, goodness cannot be explained naturalistically. Indeed, he would insist that it commits a logical fallacy which he called the “naturalistic fallacy.”

Moore’s own positive view is that goodness is a simple, non-natural property that supervenes on natural properties (where that means that if one thing has it, then anything else with a relevantly similar physical nature also has it). Its simplicity keeps goodness from being explained in terms of simpler properties, and its non-naturalness is supposed to explain its normative meaning, that is, that what has the property, goodness, ought to exist. But what is relevant here is the problem to which Moore was pointing, which is better known as the difference between fact and value. Can values be reduced to facts, or is there something inherently irreducible about them.

The most compelling argument that G. E. Moore gives for believing that there is a naturalistic fallacy is the so-called “open question argument.” Moore argues that, given any naturalistic definition of “good,” it is possible to ask meaningfully of something that is good according to that definition, “But is it good?” For example, if “good” is defined as being pleasurable, it makes sense to ask of something that is pleasurable,” But is it good?” because it might be bad, for example, because of its later consequences or because it is morally wrong. It is an open question whether something satisfying that naturalistic definition is actually good and ought to be chosen. Moore insists that the same holds of any naturalistic definition of “good.” If any such naturalistic definition of “good” were correct, Moore’s question should be as insignificant as asking, “But is the good good?” or “Is the good what ought to be chosen?” Thus, the fact that Moore’s question can be asked significantly with respect to any naturalistic definition of “good” shows that there is a naturalistic fallacy.

A. J. Ayer argued in a similar way against naturalism, albeit is as a logical positivist. He argued that if a naturalistic definition of "good" were correct, it would be self contradictory to hold that something that satisfies the definition is not good. Thus, the fact that no such proposition is self contradictory would also suggest that naturalism rest on a fallacy.

However, it is not possible to know in advance that Moore’s question will be significant with respect to every naturalistic definition of “good.” Thus, it can be argued that Moore simply had not tried the right naturalistic definition. And that is the way to refute Moore’s open question argument without denying its validity as a test for fallaciousness. (Likewise for Ayer's way of challenging the truth of naturalistic definitions of "good.")

Let us, therefore, apply Moore’s open-question argument to our ontological explanation of the nature of goodness. The issue is, then, whether it can be asked with significance, Is what contributes to natural perfection good? Or since we are talking about what is good for reason, the questions is, Is what contributes to the natural perfection of a rational being good for that rational being?

There is a way in which Moore’s question might seem significant, though it is not relevant here. It might seem significant, because one does not understand what it means to say that something contributes to natural perfection. In order to understand the question, it is necessary to understand this ontological explanation of the nature of goodness, and that means understanding its explanation of the cause of evolution and seeing how it involves an inevitable series of stages leading up to rational subjects like us. Let us assume, therefore, that the question is being asked by someone who understands the conclusions of theoretical reason about what is and recognizes herself as a rational subject of the kind they entail. That is, let us assume that it is being asked by someone at the stage of ontological philosophical spirit, that is, by ontological reason.

In that case, the answer to Moore’s open-question argument will be that it is not significant, at least, not in any way that is relevant to showing that some mistake is being made. Let us focus on the case at issue, about the goodness of the necessary goals of individual interest. The theory implies that such goals are good because they contribute in essential way to one’s natural perfection as an individual organism. To ask, But are these necessary goals good? is to ask whether one has sufficient reason to pursue them. But rational subjects do have sufficient reason to pursue goals that are good in this sense, because pursuing goals of that kind is part of their nature as rational subjects. When the rational subject recognizes that she is a being of the kind that comes to exist as a result of evolution by reproductive causation, that she is able to ask this question about whether she ought to pursue necessary goals because she is rational in the way implied by this theory, and (as we shall see) that all the goals she already takes to be good as a rational being are shown to be good by their contribution to one’s natural perfection as a rational subject, it simply does not make sense to ask if what contributes to one’s natural perfection is good. That is simply what reason does: it pursues the good in that sense.

This point can also be put from the outside, so to speak, because Moore’s question is closed by the ontological explanation of the dichotomy between theoretical and practical reason. The difference between facts and values is one of the dichotomies among arguments at the rational spiritual stage of evolution. Facts are conclusions of theoretical reason, and values are conclusions of practical reason. Ontological philosophy overcomes this dichotomy, as we have seen, by deriving the nature of reason as part of the course of evolution by reproductive causation, for that reveals that reason is a behavior guidance system that uses knowledge of the true to discover what is good. “Good” in that sense is defined as contributing to natural perfection, which is a naturalistic definition. But when we recognize that we are rational beings in that sense, then that is also what we mean by the word, “good.” To ask whether what contributes to one’s own natural perfection is good, when one accepts ontological philosophy, is as senseless as asking, But is the good good?

Likewise for Ayer's argument against a naturalistic definition of "good." For someone with ontological reason, it is self contradictory to deny that something that contributes to natural perfection is good, for that is what "good" refers to in a spatiomaterial world like our own. There simply is no other meaning that "good" could have in such a world.

The more profound refutation of the naturalistic fallacy is ontological philosophy's response to Moore, because its way of closing Moore’s open question also provides the kind of wisdom that Socrates was seeking in the name of philosophy, as love of wisdom. I am assuming that what Socrates was seeking is an explanation of the nature of goodness that would make any rational subject who understood it virtuous. That is my interpretation of the meaning of the Socratic principle: knowledge is virtue.

This is a plausible interpretation of Socrates’ argument in the Apology. When the oracle at Delphi says that Socrates is the wisest man in Athens, Socrates insists that he does not have the kind of wisdom that he takes the sophists to be claiming to have when they offer to teach virtue for a fee. In order to find out what the oracle meant, Socrates explains, he went about cross examining various kinds of respected figures in Athens about the nature of wisdom, and he found in each case that they did not have the wisdom that they claimed to have. How he showed this might be called “Socrates’ open-question argument,” because when they explained their wisdom about goodness, he was always able to point out that there was some question about whether it was really good. In the end, the only wisdom that Socrates admits to having is knowing that he does not have knowledge. But in the context of the Apology, it is clear that what he means is a knowledge about the nature of goodness that would make one virtuous, that is, the kind of wisdom that the sophists claimed to have by promising to teach virtue. Thus, the merely human wisdom that Socrates does have, which he describes by saying that he knows he does not have knowledge, can be expressed more positively as knowledge about what wisdom is, namely, that it is knowledge about the nature of goodness that would make one virtuous. That is the kind of wisdom that Socrates takes philosophy to be the love of.

Our way of closing Moore’s question is also, therefore, a way of giving Socrates the wisdom that he sought as a philosopher, or lover of wisdom. It explains not only what is good for the rational subject, but it also explains why it is good and, thus, gives the rational being a sufficient reason to choose it. The good is what contributes to one’s own natural perfection as a rational subject, and what makes the good good is that it contributes to one’s own natural perfection. The answer that Socrates was seeking is the same answer that Moore was denying was possible, namely, a self-understanding by reason that reveals how reason is related to a kind of perfection that is appropriate to the nature of what exists (including himself) in a spatiomaterial world like ours.

Thus, since ontological philosophy can explain the goodness of all the goals that we believe that rational beings pursue, it succeeds in doing what Plato tried to do for Socrates by taking an epistemological approach to philosophy. It vindicates Socrates’ merely human wisdom by showing that there is, indeed, a kind of goodness the knowledge of whose nature would make a rational being virtuous. But instead of being The Good Itself (the source of the other Forms in the realm of Being, according to Plato) what makes things good is the natural perfection that is entailed by progressive evolution, when evolution is explained as a global regularity caused ontologically by reproductive cycles and space.

Within this ontological theory, however, let me mention a way in which it might seem that Moore’s question is still open and significant (and Socrates’ quest is not fulfilled), though it comes from failing to recognize the nature of natural perfection. What generally makes Moore’s question significant when asked about other naturalistic definitions of “good” is that there are always ways that it could turn out that something that satisfies the naturalistic definition is not good because of some larger context in which it occurs where it is bad. That is, I assume, how Socrates was able to cast doubt on the wisdom about virtue that other Athenians claimed to have. But that is not possible, because of the way in which "good" is defined by ontological philosophy, that is, how it explains the nature of goodness ontologically.

In the case of hedonism, for example, Moore points out that, although defining “good” as pleasure seems plausible at first, we discover that the definition is faulty when we see that it makes sense to ask, But is pleasure good? That question makes sense because we know there are situations in which pleasure is bad. (Socrates uses this argument as well.)

But Moore’s question cannot be significant in an analogous way when applied to our definition of “good,” because there is no larger context in which what contributes to natural perfection can turn out to be bad. All the forms of natural perfection fit together as parts of the overall structure of natural perfection as a single, spatio-temporal whole, and thus, whatever is good by virtue of contributing to some form of natural perfection is good by virtue of contributing to the natural perfection of the whole. That is the unity of goodness on this theory.

It is true that what is good for one organism can be bad for another, as we have seen in the case of the predator and its prey. Eating another animal is good for the predator and bad for the prey. But this is not an ultimate conflict, because the predator catching the prey is good for the ecology, that is, contributes to the natural perfection of the ecology (not to mention how it contributes to the natural perfection of life or to the natural perfection of change).

Nor does Moore’s question become significant by wondering whether the natural perfection within which everything else is good might turn out to be bad in a still larger context, like a perfect murder or perfect tyranny. The overall structure of natural perfection includes spatially a whole planet or, perhaps eventually, a whole planetary system, and temporally, the whole course of evolution. Its larger context is the rest of the universe, with all its other stars and galaxies. But there is nothing about the large scale structure of the universe that could possibly make natural perfection bad. What we know about the rest of the universe is that evolution will follow the same course on any other suitable planet, and that can hardly make evolution in our planetary system bad. On the contrary, given the vast reaches of space separating planetary systems, the rest of the universe seems, at worst, to be indifferent to what happens on any one planet (or planetary system). It is meaningless to suggest there is some larger context in which natural perfection is bad.

There is, however, a way in which it does make sense to ask, Is what contributes to natural perfection good? But it is not a way that supports belief in a naturalistic fallacy. One could be asking if there isn’t something more to goodness, some further story to be told about its nature that is not included in the definition. That surely makes sense. What is good by our definition could be good for other reasons as well. I suggest something like that below. But what is relevant here is that the possibility of such a deeper explanation of the nature of goodness does not supply any reason to doubt that what contributes to our natural perfection is good. It merely adds to the story about why the good, so defined, is good. And far from supporting the claim that there is a logical fallacy about defining “good” naturalistically, it presupposes the possibility of such a naturalistic explanation.

There is, therefore, no naturalistic fallacy. G. E. Moore’s mistake was to infer from his own inability to find a naturalistic definition of “good” that would close his “open question” to the conclusion that there can be none. He promoted his inability to think of a naturalistic definition into a logical fallacy. But as we have seen, there is a naturalistic property to which “good” might be referring that does close his question, at least, if evolution is caused by reproduction. (The same holds for Ayer.)

In fact, the nature of the property, goodness, may also explain why Moore saw “good” as referring to a simple, non-natural property. Goodness may seem to be a simple property, for the goodness of anything actually depends on how it is part of a unique kind of structure that is as large as the planet, at least. That is why “good” cannot be defined by any set of physical properties that characterize the local objects, events and conditions that are said to be good.cxxviii And goodness seems to be non-natural, since to be good means that it ought to exist, and unless one understands the nature of the natural perfection in the world and recognizes oneself to be part of it, it is hard to see how any naturalistic property could call for things that have it to exist. Thus, by closing his open question, not only does this view of goodness show, on Moore’s own turf, that there is no naturalistic fallacy, but it also explains why Moore takes it to be a simple, non-natural property. It seems to be a simple, non-natural property because it is actually the most complex, natural property.

The autonomy of reason, as we have seen, makes the subjects who have the power of reason basically different from all other multicellular animals. It enables them to do what is good because they believe that it is good, and thus, in addition to goals that control conditions that affect their own reproduction as individuals, they can pursue goals that are good in virtue of contributing to the natural perfection of other evolving things or to artificial perfection, such as works of art. And since rational subjects will inevitably choose to pursue them, we have assumed that such goals are good for the rational subject when she chooses to pursue them. That is how we introduced the notion of optional goals for rational beings. But now that the issue arises for practical reason, it might be asked whether rational subjects ought to pursue optional goals.

Reason is autonomous, because it is the new, language-based behavior guidance system that takes over control of animal behavior as primitive spiritual animals evolve into rational spiritual animals. The animal desire to submit to the leader’s instructions becomes the desire to submit to the conclusions of practical reason, and thus, reason wrests control of behavior from (other) animal desires (that is, from control by the goal selection system of the multicellular animal behavior guidance system). That is, as we have seen, what makes it possible for the rational subject to puruse what she believes are necessary goals of individual self interest, even when it is opposed by strong immediate desires. But since reason works by enabling the subject to intend and actually do what she believes is good, it also enables her to pursue goals beyond those that control conditions that affect her individual reproduction, or optional goals.

Optional goals include all goals that are good for other reproducing structures, the ecology, life, or change because of how they contribute to their natural perfection, as well as what is good in virtue of contributing to artificial perfection. They include, for example, doing good for other individual rational beings (beyond what is required by morality, that is, as supererogation), making contributions to culture (beyond the normal rational interest in knowing the good, the true and the beautiful), serving the interest of one’s spiritual animal (beyond duty), doing good for other spiritual animals, for the ecology, for life, or for evolution generally. And optional goals include creating or enjoying works of art, including not only works of fine art, but also the aesthetic aspect of one’s daily life.

It is good to pursue optional goals, however, only insofar as necessary goals are already being attained. Necessary goals take priority over optional goals. But the power of reason is so great that rational beings are often in situations where they are able to control more conditions in the world than what affects their individual reproduction, and they spend their extra rational action on optional goals. The choice of such goals is what makes them good for the rational subject. But as rational subjects, they cannot choose to pursue any goal unless they believe (correctly or mistakenly) that it is already good in some way, that is, by contributing to the natural or artificial perfection of something. The autonomy of reason is the power to do what they believe is good, not the power to act arbitrarily or capriciously.

The natural (or artificial) perfection of other things in the world is often something that rational subjects can detect, because rational imagination enables rational subjects to see the actual against the background of the possible and that can reveal ways in which the whole is an optimal part-whole relation. The rational interest in beauty is also what enables rational subjects to see how best to control all the conditions that affect their individual reproduction, not to mention what enables them to judge what is true. It plays the same role in the choice of optional goals and pursuing them.

When a rational subject pursues an optional goal, she is guided by the perception of what is good for something other than herself, that is, by her perception of how it contributes to some other natural perfection. The judgment of what it is good to do is disinterested, because it depends of her belief about what is good for it. This is true even in the case of a work of art. What is good for the work of art is not what contributes to the natural perfection of something that is already evolving, because it does not even exist until the artist chooses to create it. But it does have an optimal part-whole relation, which is called beauty, and thus, it is like natural perfection and recognized by rational imagination in the same way. Artists testify that, as the work of art grows, it “calls for” certain additions so that the artist is merely ministering to its needs. That is the sense in which works of art imitate nature: the beauty of art is the imitation of the natural perfection found in nature. It is artificial perfection.

To say that rational subjects can choose to do what is good because they believe that it is good, even when it does not control relevant conditions, is not to deny that they may also have a desire to pursue that goal. It is only to say that the desire to pursue the goal is not what makes it good.

Desire may prompt the choice of one optional goal over another, for example, when the desire to listen to music leads one to become a musician or even just to listen to music. But that is not what makes the goal good. What makes it good is that what one is listening to or adding to the whole makes an essential contribution to the optimal part-whole relation of the work of art itself. Likewise, a benevolent desire may prompt her to take an interest in the good of someone else, but what makes the rational subject’s actions in pursuit of it good is not how it satisfies that benevolent desire, but how it contributes to the other’s natural perfection and, by doing so, contributes to her own natural perfection.

Moreover, once one has chosen music, say, as an optional goal, the desire that is the source of the enjoyment one gets from pursuing it is not merely the desire that prompted the choice in the first place. What the rational subject learns about its natural perfection in pursuing the optional goal transforms that desire. Not only does she come to enjoy new aspects of music, or whatever the object, but she also enjoys them for other reasons, having to do with how they contribute to the natural perfection of the whole. The desire that is being satisfied is ultimately the desire to submit to reason, though given how reason grows and matures with the rational pursuit of optional goals, it might be better called the desire to enjoy the power of reason.

It is the nature of rational imagination that leads us, as we have seen, to appreciate aesthetic goodness. The perception of beauty is implicitly the recognition of perfection, and that is what accounts for our response to it. In perceiving that nothing can be done to make it better, reason would have us leave it as it is and simply enjoy it.

However, if goals are not good because they satisfy desire, but rather because of the relevant conditions they control, as our ontological explanation of goodness and our functional explanation of desire imply, one might doubt that optional goals are good at all. Since they do not control conditions that affect the rational subjects reproduction as an individual, what makes them good?

It is clear that optional goals are not good for rational subjects in the same way that the goals of behavior in other multicellular animals are good for them, because the attainment of optional goals does not control “relevant conditions” in the sense of conditions that affect the rational subject’s reproduction as an individual. Controlling them does not necessarily make the individual better able to reproduce. Thus, ontological philosophy cannot explain why optional goals are good for the individual in exactly the same way as it does necessary goals.

Ontological philosophy does, however, imply that it is good for rational beings to pursue optional goals, because it explains the nature of goodness as contributing to natural perfection, not necessarily as contributing to its own maximum power to control conditions that affect its own reproduction. The latter is merely how the power to contribute to natural perfection is usually brought into being in a spatiomaterial world like ours.

The power of reason makes rational subjects essentially different from other multicellular animals, indeed, from all other organisms (except spiritual animals), and that means that their natural perfection is different from other animals. Though other organisms can only evolve behavior (and other structural effects) that control conditions that affect their own reproduction, that limitation is lifted in the case of rational beings, because reason guides behavior as a result of a cultural evolution of arguments that discover the true, the good and the beautiful. It is a behavior guidance system that is able to tell what is good more generally than by pursuing goals dictated by the biological behavior guidance system and what can evolve biologically by natural selection. It enables rational subjects to do what is good simply because they believe that it is good. Furthermore, since reason often gives rational beings more power than they need to control relevant conditions, the natural perfection of rational beings is not just the maximum power to control all conditions that affect individual reproduction. It is the maximum power to control conditions generally that are good.

In other words, the fact that a power to contribute to natural perfection does not evolve by making the organism better able to complete its own reproductive cycle does not imply that it is not good. Reproductive causation is merely what is usually responsible for the existence of such powers in the world. And if at later stakes in evolution, organisms acquire powers of that kind without being naturally selected for having them, that does not mean that they are not good. Given the nature of goodness, any contribution to the natural perfection of the whole of which something is part is good, regardless how it comes to exist in the world. That is something that reason enables the rational subject to recognize, though that is not why reason evolved in the first place.

Perfection is an optimal part-whole relation in which the whole does the most with the least, and in the case of natural perfection, it is an optimal part-whole relation in which the whole has as much power to use free energy to control what happens in the world with the fewest and simplest structural causes as possible. In the case of reason, the structural causes are the sources of rational action, that is, the use of practical arguments to guide one’s behavior toward the good. Thus, the optimum cannot be a matter of using the fewest and simplest structural causes to attain some given ends, for there is a fixed supply of structural causes, namely, all the behavior of a rational subject over her lifetime. In this case, the part-whole relation does more with less by using the structural causes already available to do more, that is, to control more of what happens in the world.

Nor is there any question about what counts as more or less control of what happens in the world, because optional goals are goals that control conditions that contribute to natural (or artificial) perfection in some way or other. Though they may not control conditions that affect one’s own reproduction, optional goals are not arbitrary or random changes in the world. They are not chosen by reason unless they are seen as contributing to the natural perfection of some other organism, to some other form of natural perfection, such as the ecology or evolution, or to an artificial perfection that imitates natural perfection, such as works of art.

Thus, the natural perfection of rational beings is more like the natural perfection of life than the natural perfection of organisms. New levels of part-whole complexity in the structures of reproducing organisms contribute to the natural perfection of life not because they control conditions that are already relevant to reproduction, but rather because their higher level of organization makes new conditions relevant and brings new conditions under control, extending the power of life as such to control what happens in the world. Likewise, what contributes to the natural perfection of reason is what increases the power to control what happens in the world, not to control conditions that are relevant to its own reproduction. In both cases, however, the new conditions brought under control are not arbitrary, but are good because they contribute to natural (or artificial) perfection in some way.

Rational subjects ought, therefore, to choose optional goals and pursue them. Though the optional goals themselves are not necessary, it is a necessary goal of rational subjects to pursue some optional goals or others, if they have the extra power to do so. It contributes to their natural perfection as rational subjects, even though those goals do not control conditions that are relevant to their own reproduction. The pursuit of optional goals is, therefore, good for rational subjects.

Thus, it is possible for ontological philosophy to answer G. E. Moore’s doubts about the possibility of any such naturalistic explanation of the goodness of optional goals in the same way as it did necessary goals. To a rational subject who understands her nature as a rational subject and her place in the natural world, it simply does not make sense to ask, But is contributing to one’s own natural perfection good?

The pursuit of optional goals is also part of the wisdom that Socrates was seeking, because this ontological explanation of the nature of goodness explains why optional goals are good for the rational subject. And the pursuit of any optional goal that one has chosen is good, because the pursuit of optional goals is good for rational beings and this goal is the one that the rational subject has chosen.

Ethics

Reason has another practical interest, in addition to the individual interest of each subject, because it also has the function of guiding the behavior of the spiritual animal as a whole. The goals of the spiritual animal are good for rational beings in the same way as the goals of individual rational subjects, and there is also a difference in the goals pursued by spiritual animals between necessary and optional goals. But since all these goals, necessary and optional for both individual subjects and spiritual animals, are goals pursued by rational subjects according to arguments that evolve by rational selection, there must be priorities among them. Those priorities are set by rules of morality and rules of justice, and both sets of rules are good for reason in the same way, that is, by contributing to the natural perfection of reason.

What is good for spiritual animals is not necessarily the same as what is good for rational subjects, because spiritual animals evolve by reproductive causation on the social level of biological organization at the same time that rational subjects evolve by reproductive causation on the individual (or multicellular) level of biological organization. Though they depend on one another for their existence, each approaches the natural perfection for organisms of its own kind. At the same time that spiritual animal are becoming naturally perfect as social level animals made of rational subjects as parts, rational subjects become naturally perfect as multicellular level animals that live as parts of spiritual animals.

As a higher level of biological organization, spiritual animals depend for their existence on the coordination of rational subjects as lower level organisms. But the part-whole relation that holds between the spiritual animal and its members is, as we have seen, different from that between the multicellular animal and the cells that are it parts.

In both cases, what is good for the whole is usually good for the parts (because they are parts of the whole), but it can sometimes be bad for the parts as well. For example, the good of the whole sometimes requires the sacrifice of some of its parts. In spiritual animals, this happens in warfare, when some individuals must die, and in multicellular animals, the death of cells is a normal part of the process of development, for example, in the nervous system.

But there is a difference in how the good for the parts is related to the good of the whole. In both cases, it is generally true that what is good for the parts is also good for the whole, because the whole is made up of the parts and depends on them for its own existence. Indeed, in multicellular animals, what is good for the cell is never bad for the whole, because the only way that goals can be naturally selected for a cell is by the success of the multicellular whole in reproducing, that is, by natural selection at the higher level of biological organization. The cells cannot complete reproductive cycles on their own, independently of the multicellular reproductive cycle. In spiritual animals, however, what is good for the rational subject may be bad for the spiritual animal of which it is part, because its goals are naturally selected for the rational subject by how they contribute to individual reproduction, not just the reproduction of the spiritual animal as a whole. That is, individuals do reproduce independently of the reproduction of their spiritual animal. Thus, for example, some of the goals that rational subjects pursue because they contribute to their individual interest may be immoral or treacherous and, thus, harmful to the spiritual animal.

Instead of subordinating the good of the part to the good of the whole, therefore, the good for the individual and the good for spiritual animal are on a par. They are good for the same kinds of reasons, though on different levels of biological organization. And they are both good for the rational subject, for he is the agent of rational beings generally (that is, for the individual, the spiritual animal, and as we shall see, even for the world as a whole). Thus, individual and spiritual goals are both goals of the self, as the four-dimensional being that one constructs by his rational actions over a lifetime, and conflicts between individual and spiritual self interest must be resolved, or else reason will not be able to serve its function. They are resolved, as we shall see, by a symmetrical subordination of the good of each for the good of the other.

Spiritual animals pursue goals by way of institutions that generate social level behavior. (Institutions are patterns of interaction among members guided by low-level practical arguments about social roles and their duties, prerogatives and interrelationships, and their functions are the social level behavior they generate.) When choices must be made among social level goals, it is the function of political institutions, or government, to make the choice for the spiritual animal. And parallel to rational subjects, there is a difference between goals that are necessary and goals that are optional.

Spiritual animals have necessary goals. Goals that control conditions that affect the reproduction of the spiritual animal as a whole are necessary goals. Though spiritual animals, unlike multicellular animals, can continue to exist indefinitely without reproducing, there are nonetheless relevant conditions to be controlled. They must be able to reproduce, if the occasion arises, in order to be naturally perfect. Though reproduction is not a necessary goal of spiritual animals, it is the criterion of which other goals are necessary. And among their necessary goals, two kinds can be distinguished, because the social level behavior in pursuit of goals can be directed either at objects external to the spiritual animal or at its own members.

External necessary goals of spiritual animals are analogous to those of multicellular animals, except for warfare, the new kind of behavior that spiritual animals have toward one another.

Like multicellular animals, spiritual animals must acquire from nature the free energy and other resources they need to fuel their reproductive cycles (This aspect of the economic institution corresponds to feeding in other animals.) Spiritual animals must also protect themselves from natural hazards such as predators, storms and other disasters. And just as multicellular animals must mate, nomadic spiritual animals, at least, must maintain relations to other spiritual animals (such as membership in tribes) by which its members can mate outside their own spiritual animal.

The non-analogous goals arise from group-level natural selection of spiritual animals by war. The overriding goal of a spiritual animal in dealing with other spiritual animals is to wining at war with them, which involves making the best choice about whether (and how) to live peacefully or to engage in war relative to other spiritual animals with which it interacts.

Internal goals of animal behavior are unique to spiritual animals, because in spiritual animals, the animal behavior guidance system also serves as the biological behavior guidance system, that is, as the mechanism that coordinates the behavior of the lower level organisms of which it is composed. Thus, social level animal behavior must serve many of the same functions as the biological behavior guidance system in multicellular animals.

The economic institution also includes internal functions, such as coordinating the productive behavior of members and distributing the products, just as acquiring energy requires digestion and circulation in multicellular animals. Likewise, the government includes executive institutions that administer regulations, just as the brain has nervous connections to the rest of the body. But it also includes an institution for enforcing laws by punishment, which is analogous to the immune system in multicellular animals. The kinship system gives individuals locations in the spiritual body, corresponding to a process of embryological development for determining cells to certain parts of the body. Educational and religious institutions acculturate the members to the arguments that will guide their behavior, just as the endocrine system and parasympathetic nervous system guide the behavior of individual cells.

Some goals of internal behavior have no analogue in multicellular animals. For example, spiritual animals may have institutions that mediate the exchange of arguments and promote cultural evolution, such as academic, scholarly, and research institutions. Nothing like cultural evolution takes place in multicellular animals.

Some internal goals of social level behavior are especially relevant to practical reason because they have to do with controlling the pursuit of individual goals. The health of the spiritual animal requires that its members observe moral rules that limit the pursuit of the individual interests, for unless they are observed, members will not be willing and able to cooperate in generating social level behavior.

The content of moral rules is determined as the conclusions of practical arguments about how individuals should behave in situations that affect others or the spiritual animal as a whole. As we have seen, they include rules that require everyone to cooperate in generating social level behavior (including prohibition of treason and other crimes against the spiritual animal).They also include rules that prevent members from harming one another, rules that enable members to cooperate with one another (such as the duty of fidelity in promises and contracts) and facilitate cooperative attitudes (such as the duty of reciprocity in gift giving and civility.

Because practical arguments evolve when they are rationally selected by everyone, as we have seen, the rules tend to be the rules that maximize the good of the whole (as the utilitarians hold), that maximize the freedom of everyone (that is, minimize the limits they impose on the pursuit of individual goals, as the contractarians hold), and treat members equally (as Kantians insist).

The spiritual animal must act as a whole on its members to ensure that moral rules are followed. Violations of moral rules arouse anger in those who are hurt, and the motives selected for fighting wars tend to take the form of revenge and vendettas within spiritual animals, unless measures are taken to restore the moral equilibrium. The institutions that have traditionally served this function are the religious institutions, which publicly affirm and defend the principles on which other practical arguments are based, and the justice system (including the police and judicial system), which punish wrongdoing. (The former is part of the educational systems, analogous to the endocrine and parasympathetic nervous system in multicellular animals, whereas the justice system corresponds to the immune system, which kills mis-functioning cells in the body as well as invaders.)

Though many violations of moral rules are naturally sanctioned by the disapproval of other members, some violations of moral rules are so harmful and cause so much warlike antagonism that they are prohibited by laws, and retributive justice is reserved for them. Punishment of crime is a necessary goal of spiritual animals, if only because taking revenge on the individual level leads to civil war.

Rational subjects, therefore, insofar as they are responsible for selecting and generating social level behavior, ought to choose to pursue these goals. The attainment of these goals contributes to the natural perfection of the spiritual animal, because it controls the conditions that affect its reproduction as a whole. These goals are, therefore, good for reason in its function of guiding the behavior of the spiritual animal.

In response to Moore’s open question argument, therefore, it will not make sense for rational beings who understand the nature of reason and its place in the natural world to ask, But is what contributes to the natural perfection of spiritual animals good?

The pursuit of these necessary goals is also part of the wisdom that Socrates was seeking, because this ontological explanation of the nature of goodness explains why necessary goals are good for the spiritual animal.

There are optional goals of spiritual interest. Just as individuals can pursue goals because they are good even when they do not control conditions that affect individual reproduction, so spiritual animals can pursue goals that are good when they do not control conditions that affect its social level reproduction. Though in both cases the goal must already be good in some way (by contributing to the natural perfection of something, including artifacts), the goal becomes good for reason because it is chosen.

For the spiritual animal to pursue optional goals, a general consensus about them is normally required, because they are not necessary and pursuing them will involve the cost of generating social level behavior. But since there are goals that it would be good for spiritual animals to pursue, it is possible to make them good for spiritual animals by choosing them.

Though it is a necessary goal of spiritual animals to protect the environment from the damage of its own economic activity enough to survive indefinitely into the future, an optional goal might be to preserve as many species and ancient ecologies as possible in order to insure the diversity of life on earth.

It is a necessary goal of spiritual animals to make sure that they will win any wars they may fight, since that is a condition that affects their reproduction as a whole. But an optional goal would be to work together with other spiritual animals to end group level natural selection by war. That would require the control of population growth everywhere on the planet, including perhaps even decreasing it, since that is the basic cause of war and would eventually lead to war, unless it is controlled. Under such conditions it might be possible for spiritual animals to end war by cooperating in an international military force to protect national boundaries and prevent spiritual animals from harming one another. (Insofar as there are traits that spiritual animals would otherwise evolve by such group level natural selection which make them more perfect, it might also be necessary for spiritual animals to assume responsibility for giving spiritual animals those powers by other means.)

Natural selection at the individual level continues after a fashion within spiritual animals by success in individual reproduction, but it is significantly curtailed by modern medicine and where it is still at work, it involves much suffering. Thus, an optional goal for spiritual animals would be to replace natural selection with germ line intervention in order to eliminate genetic diseases and to enhance the powers that enable rational subjects to attain the goals they ought to pursue. For example, each couple could be given the option of adding or deleting certain genes from their offspring, and since they would choose what is best for their children, it would be decentralized process much like natural selection in which rational subjects could be expected to evolve further in the direction of natural perfection for organisms of their kind. It would be to replace natural selection at the individual level with rational selection.

Traditional optional goals have included building monuments. But a more up to date goal that may be optional for spiritual animals is space exploration and colonizing the rest of the planetary system. But there are other possible goals. In each case, it is not clear at this point in evolution whether these goals are optional or necessary. That is why the future course of evolution is not just a conclusion of theoretical reason, but with the evolution of reason’s ontological self-understanding, depends on where practical reasoning leads reason in the situations that arise.

The pursuit of goals of the spiritual animal may conflict with the rational subject’s pursuit of individual goals, and since they are both goals of rational beings, there is a conflict among goals that needs to be resolved.

The individual interest and the spiritual interest are equal, because they are good in parallel ways, that is, each by contributing to the natural perfection of the organism (or primary structure) on its own level of biological organization, and ontological philosophy provides no grounds for preferring one over the other. Both are equally the responsibility of reason, or goals pursued by reflective subjects as the agents of reason, and thus, it is a conflict between one's individual self interest and one's spiritual self interest.

When individual and spiritual goals conflict, what ought to exist for reason is what contributes to the natural perfection of reason as the behavior guidance system for both biological levels, that is, for the rational subject as a rational being. But what are those priorities.

Moral rules are generally assumed to take priority over the pursuit of individual goals. Indeed, that is their function: moral rules are meant to limit the pursuit of individual self interest. The general observance of moral rules is, as we have seen, a necessary goal of spiritual animals, for spiritual animals cannot pursue social level goals except by coordinating the behavior of its members and their ability to cooperate in pursuit of such goals depends on the members being moral in their relations to one another. But when moral rules do conflict with the pursuit of individual self interest, why should the rational subject be moral?

Let us recall the answers to this question at earlier points in evolution. Answers at the stage of rational spiritual animals are based on religion, but the answers given by epistemological philosophy are no more adequate.

Rational culture evolves arguments to justify the principles on which its practical arguments are based, and they generally have to do with explanations of the origin of the world, the place of rational beings in it, and the purpose in their existence. These arguments serve the function of mutually acknowledging the validity of the culture of one’s spiritual animal, but they are not rationally compelling. Religious beliefs are typically about gods or superior beings of some kind, which may be interpreted as representations of the spiritual animal and its interest. But in order to justify being moral, rather than pursuing their individual interest (or acting on emotion), they merely assert the priority of spiritual interest over individual interest. Though it may be obvious that being moral is in the spiritual interest, that is, good for the group as a whole, religion does not explain why the spiritual interest is prior to the individual interest.

Philosophical culture has attempted to give a deeper justification of moral rules. In the ancient and medieval period and continuing long into the modern period, the belief was that the reason for being moral, as well as the content of moral rules, has to do with something about the nature of goodness and, thus, is objective. Plato thought that the nature of goodness is explained by the existence of The Good Itself as the source of the other Forms — and, thus, of the goodness of visible objects that participate in the Forms as well. That was meant to explain why rational subjects ought to be moral in a way that would satisfy Socrates, that is, by making rational subjects virtuous. But Plato could never explain the nature of The Good Itself in a way that showed how it made other Forms good, much less why rational subjects should be moral.

It was possible to preserve Plato’s belief in the objective nature of goodness in the medieval period (and the early modern period) despite the inability to give an adequate explanation of the nature of goodness. The Christian view, in its most mature form, holds that it is God who understands the nature of goodness, whereas finite rational beings like us cannot. That is, God's ultimate purposes are said to be inscrutable. Insofar as we do not understand why we ought to be moral, therefore, we must so as a matter of faith. Though it is a faith that there is something about the nature of goodness from a God’s Eye point of view that makes morality prior to individual interest, it is still not reason that explains why we ought to be moral.

In the modern period, attempts to give a naturalistic explanation of the goodness of morality that would explain why we ought to be moral were ultimately failures. Hobbes, as a social contractarian, attempted to explain the content of moral rules as the result of a contract in which every rational subject gives up only as much freedom as is required to protect individuals generally from harming one another and enabling them to cooperate. But since that did not explain why the individual should not be immoral in pursuing his individual interest after the social contrast was signed and he could avoid being punished, it did not explain adequately why the morally good is good.

Kant attempted to explain the content of moral rules as what is required by universalizability, that is, his categorical imperative (that we should act only on those maxims that we can will to be a universal law of nature). But that left Kant with no way to show that individuals ought to be moral, because it did not give the individual any reason for choosing not to be rational in that sense, and being rational only in the sense of pursuing is rational individual interest. Kant suggested that the reason stems from something uniquely valuable about rational subjects, that is, as ends in themselves, but he was never able to explain what that was, except to suggest that is has something to do with the unknown (noumenal) nature of rational subjects and to suggest that freedom from pursuing goals set by one’s desires, or what he called “autonomy,” is somehow better.

Utilitarians, such as Bentham and Mill, explained the content of moral rules as what promotes the general happiness, but they too failed to explain why the rational subject should be moral. They assumed that the individual subject cannot help but pursue his individual happiness, but they were never able to explain why the individual should prefer the general happiness to his own happiness when they came into conflict.

Ontological philosophy does, however, explain why we should be moral. Its explanation of the nature of rational beings and the nature of goodness explains not only the content of moral rules, as we have seen, but also why the individual rational subject should take moral rules as prior to individual interest. The foundation of the priority of moral rules is that the spiritual interest is one of the basic interests of the rational subject. Because of the nature of reason and the way in which it works, the individual has, as a rational being, responsibility for guiding the behavior of the spiritual animal as well as his own individual behavior.

Reason evolved originally, as we have seen, with the function of guiding the behavior of spiritual animals to make reliable choices about war and peace. But since it works by the exchange of practical arguments among members and their rational selection by individual rational subjects (that is, the selection of arguments from among the alternatives that make their world views maximally coherent), it could also be used to guide individual behavior. In the case of guiding the behavior of the spiritual animal, however, not only the discovery of what is good, but also the selection and generation of social level behavior depends on the members coming to agree about what the spiritual animal ought to do (though, in practice, social level behavior may be guided by political institutions that are maintained by mutual agreement about the practical arguments that generate them). Given the way that reason functions as a behavior guidance system for the spiritual animal, therefore, the rational subject has, as a rational being, an interest in pursuing the goals of the spiritual animal. The rational subject is responsible for social level behavior and they contribute to the natural perfection of the whole of which he is part. And being moral is the most basic way that the individual contributes to the natural perfection of his spiritual animal.

It should be emphasized that the spiritual interest of the rational subject is different from his individual self interest in the spiritual animal because of how he depends on it as the means to pursuing his individual goals. First of all, the spiritual animal is the whole of which he is part, the context of all his activity, and thus, his welfare depends on its welfare. But furthermore, most of the goals he pursues depend on having the use of a spiritual body, as well as a physical body (in the sense that the means involve the cooperation of other members of his spiritual animal). Since his spiritual body is a most powerful means to attaining goals that are good for him as an individual, the individual has another interest in the good of the spiritual animal. But this is not his spiritual self interest. It is his individual self interest in his spiritual animal as the whole of which he is part and his individual self interest in having the use of a spiritual body.

Thus, the subject has necessarily, as a rational being, a spiritual self interest distinct from his individual self interest. And being moral is in his spiritual interest. But it may seem that it is not possible for ontological philosophy to explain why the rational subject ought to be moral, because when moral rules require limiting the pursuit of individual goals, there is a conflict between his two basic interests. They are equal interests, according to ontological philosophy, because they both arise in the same way (by contributing to the natural perfection of the organism on its level of biological organization) and the rational subject is responsible for both. They do come into conflict, because moral rules are meant to limit the pursuit of individual goals. It may seem, therefore, that ontological philosophy is inherently unable to explain why he ought prefer on to the other.

There is, however, a sufficient reason for being moral, because there is a simple and straightforward optimal resolution of this conflict which comes from recognizing the difference between necessary and optional goals of individual self interest. That is, submitting to moral rules is good for the rational subject because it contributes to the natural perfection of the whole of which the rational subject.

It is a necessary goal of the spiritual animal that its members observe moral rules, because that is a condition that affects its reproduction as a whole. The spiritual animal cannot act at all unless morality prevails, because that relationship among its parts is essential to its health.

On the other side, it is not a necessary goal for the individual to act contrary to moral rules. Moral rules limit the means the individual uses to attain individual goals, but they do not prevent him from attaining his necessary goals, at least, not in a healthy spiritual animal. In healthy spiritual animals, individuals are able to attain their necessary goals by moral means, if they make a reasonable effort. Thus, necessary individual goals never conflict with the necessary spiritual goal of being moral. Though moral rules may limit how the individual pursues necessary individual goals, that is merely to constrain his pursuit of his optional individual goals, for there are other ways to attain them and one way is good for the individual only because he chooses it.

To be sure, moral rules may make it impossible to pursue some optional goals at all. But since optional goals are good for the individual only because he chooses them, the individual can contribute to the natural perfection of the whole of which he is part by constraining his choices of optional goals in such a way that his pursuit of them does not involve the violation of moral rules. That is not a severe limitation on individual interest, because there are so many good goals to choose from in making goals good for himself. Thus, there is obviously a best way to maximize the attainment of the goals that are good for rational subjects, including both his individual and his spiritual self interest, and it involves being moral.

This implies, however, that in situations where following moral rules would make it impossible to attain the necessary goals of individual interest with a reasonable effort, it is not wrong to violate moral rules. But that is not surprising, because when the spiritual animal is not healthy enough to continue to exist, it does not contribute to the natural perfection of the whole of which the individual is part to pursue the goals that are necessary for the spiritual animal.

Rational subjects ought, therefore, to observe moral limits on their pursuit of individual goals, because it contributes to the natural perfection of the whole of which the rational subject is part. In this case, however, the whole is a unique combination of animals (or primary structures) at two different levels of biological organization, because the rational subject, as the agent of reason, is responsible for both. The priority of morality is a necessary goal of the spiritual animal (in virtue of controlling a condition that affects its reproduction as a whole), and since it does not conflict with any necessary goal of individual interest, being moral is what contributes to the natural perfection of their combination. Thus, it is good for rational subjects to take morality as prior to their individual interest.

In response to Moore’s open question argument, once again, it will not make sense for rational beings who understand the nature of reason and its place in the natural world to ask, But is what contributes to the natural perfection of both spiritual animals and their members good?

This reason for being moral is also part of the wisdom that Socrates was seeking, because this ontological explanation of the nature of goodness explains why the priority of moral rules is good for the rational subject.

What makes this an adequate explanation of why it is good for the rational subject to be moral is the assumption that moral rules do not conflict with the attainment of necessary goals of his individual self interest. But morality is not the only way that his spiritual interest can conflict with his individual interest. The pursuit of optional goals of the spiritual animal may conflict with the rational subject’s pursuit of necessary goals of individual interest, and thus, there is another conflict among goals that needs to be resolved.

Conflicts clearly do occur between goals of the spiritual animal and the necessary goals of the individual. Spiritual animals often find it useful to sacrifice some of its members in pursuing its social level goals, especially in civilized societies, where a class structure gives some members enormous power over other members, and in mass societies, where subgroups are historically antagonistic with one another. The history of oppression shows that this possibility has been actualized far too often.

One kind of conflict between spiritual and individual goals is so basic to the existence of both, however, that its burden on individuals cannot be counted as contrary to the necessary goals of individual self interest. That is the need of individual members to risk their lives in war. War is the inevitable form of group level natural selection that is responsible for the evolution of rational spiritual animals, and thus, neither spiritual animals nor rational beings can exist without accepting the burdens of fighting. The sacrifice of individuals in war does not, therefore, conflict with the attainment of necessary goals of individual self interest in the relevant sense.

The same may be said about dealing with natural disasters, insofar as group level action that sacrifices individual members is required to control conditions that affect the reproduction of the spiritual animal as a whole.

The rules of justice are meant to limit spiritual animals in the pursuit of its social goals in order to protect the rights of individuals. They are generally formulated in terms of inviolable individual rights because they are meant to protect individual rational subjects from being sacrificed unnecessarily in the pursuit of spiritual goals. Such rights include the most basic means by which rational subjects pursue goals of individual interest, both necessary and optional. Such rights include all the means the rational subject must have in order to attain necessary goals of their individual interest, and there are two general classes of them: basic liberties and distributive justice.

Basic liberties. Rational subjects must have the basic means required to attain necessary goals and lead a normal life, including the right to lead one’s life free from unreasonable arrest or other unnecessary restrictions, the right to speak, associate and contract with other people in public, the right to hold the beliefs that one takes to be true, the right to an equal opportunity to pursue optional goals and the like.

Distributive justice. Rational subjects must have enough economic power to be able, with a reasonable effort, to provide the material conditions of life, including the means for attaining necessary goals, such as food, shelter, medicine, and the capacity to have a normal social life.

But when spiritual goals do conflict with necessary goals of individual self interest, why should the spiritual animal observe rules of justice? This is the mirror image of the issue about the priority of moral rules over the pursuit of goals of individual interest. We are asking why the rules of justice are prior to the pursuit of goals of spiritual self interest?

All the goals are goals for reason, that is, for rational subjects acting in their capacity as the behavior guidance system for both the individual and spiritual animal, and what ought to exist depends on what contributes to the natural perfection of the whole, including both the spiritual animal and its members.

The individual self interest and the spiritual self interest are equal, because they are good in parallel ways, that is, each by contributing to the natural perfection of the organism (or primary structure) on its level of biological organization, and ontological philosophy provides no grounds for preferring one over the other. Both are equally the responsibility of reason.

When individual and spiritual goals conflict, what ought to exist for reason is what contributes to the natural perfection of reason as the behavior guidance system for both biological levels, that is, for the rational subject as a rational being. But what are the priorities?

What makes an optimal balance of individual and spiritual interests possible is that the necessary goals of individual and spiritual self interest can both normally be attained without conflict. After all, spiritual animals are viable organisms. They could not have evolved in the first place unless groups of multicellular animals with coordinated behavior were better able to control the conditions affecting both reproduction on both the individual and social level.

The compatibility of their necessary goals means that only optional goals need to be restricted for the good of necessary goals. We have assumed all along that necessary goals at each biological level take priority over the optional goals at that level. And we have just seen that the necessary goals of spiritual interest take precedence over the optional goals of individual interest. Thus, to see the optimal resolution in this case, we need only consider how necessary goals of individual interest take precedence, in the same way, over optional goals of spiritual interest.

The resolution of this conflict between individual and spiritual interest is the mirror image of the resolution that explained why moral rules takes priority over the pursuit of goals in one’s individual interest. In this case, it explain why rules of justice take priority over the pursuit of goals in one’s spiritual interest.

In both cases, the necessary goals of one biological level take precedence over the optional goals of the other level. That is a symmetrical relationship. And in both cases, that priority determines what is good for reason because it is what contributes to the natural perfection of the whole of which rational subjects are part, that is, the unique combination of reproducing organisms (or primary structures) that have evolved by reproductive causation at two levels of biological at once. (The priorities are depicted in the diagram of the symmetry of individual and spiritual interests).

Rules of justice limit the pursuit of goals of spiritual interest in the same way that rules of morality limits the pursuit of goals of individual interest. In both cases, the necessary goals of one interest are the foundation for limits on the pursuit of goals of the other interest. But they limit the pursuit of necessary goals in a different way from how they limit the pursuit of optional goals. They limit only the means to the attainment of necessary goals, but they can limit the pursuit of certain kinds of optional goals.

The necessary goals of individual interest limit how the spiritual animal pursues its necessary social level goals (just as moral rules limit how the rational subject pursues its necessary individual goals). Though there are certain goals that spiritual animals must attain, there are ways of attaining them that do not keep individual from pursuing their necessary individual goals.

This is not to say that the spiritual animal cannot sacrifice the property and even the lives of individual members in pursuit of necessary goals, such as victory at war and protecting against natural disasters. But those exceptions are already included. Avoiding the risk of war or avoiding mutual defense against natural disasters is not a possible means of controlling conditions affecting individual reproduction for members of spiritual animals, and thus, they are not necessary goals of individual self interest in the first place. Mutual protection from predators (and other natural disasters) and fighting wars have been necessary to the existence of the spiritual animal from the beginning. But individual rights protect the means that spiritual animals use to attain such necessary individual goals within the limits of morality, and no infringement on the rights of individual is justified.

Rules of justice would limit the optional goals that the spiritual animal can choose (just as moral rules limit the optional goals that rational subjects can choose). There may be optional spiritual goals that the spiritual animal is not permitted to pursue because they would conflict with individuals pursuing their necessary individual goals. But that is not a severe limitation on spiritual animals since optional goals are good for spiritual animals only because they are chosen and there are plenty of other optional spiritual goals on which spiritual animals may spend their extra power of rational coordinated action.

For example, the spiritual animal would not be justified in sacrificing the life of one member to use various of his organs to save the lives of several other rational subjects, even though that may maximize the total happiness, because maximizing happiness is an optional goal and it would violate his right to life. (Individuals may, of course, contract with others to set up such an arrangement, and the spiritual animal might be in the position of having to enforce the contract. But what makes the arrangement good is that it serves the individual interests of the participants, and what makes it good for the spiritual animal to enforce it, if it is, is that it is good to keep the contracts one makes.)

There may be conflicts between optional spiritual goals and optional individual goals. They will be limited if spiritual animals pursue optional goals only when there is a consensus about them, because the individuals would all contract, in effect, to cooperate in some social level goal. But if there are conflicts between optional goals on the individual and social biological levels, they do not pose any basic problem about what contributes to the natural perfection of the whole, that is, both the spiritual animal and its members, because optional goals are good for reason only because they are chosen and no matter how much extra power rational beings may have, there are plenty of optional goals to choose from.

The symmetry between the individual and spiritual interests of rational beings makes it clear, therefore, which goals contribute to the natural perfection of the whole of which reason is part, including both the spiritual animal and its members. Rational subjects acting in their individual self interest ought to observe moral rules, and rational subjects acting in their spiritual self interest (that is, in guiding social level behavior) ought to observe rules of justice, including both basic liberties and distributive justice (the economic means to attain necessary individual goals). This is the way to maximize the attainment of all the goals being pursued by rational beings, for by including the attainment of necessary goals on both levels, it makes it possible to pursue optional goals on both level of biological organization. Thus, it is the set of priorities that contributes to the natural perfection of rational beings. Thus, it is good to be moral and to be just.

In response to Moore’s open question argument, once again, it will not make sense for rational beings who understand the nature of reason and its place in the natural world to ask, But is what contributes to the natural perfection of both spiritual animals and their members good?

This reason for being moral is also part of the wisdom that Socrates was seeking, because this ontological explanation of the nature of goodness explains why the priority of moral rules is good for the rational subject.

Religion

The one remaining question is whether there is any other practical interest of reason. The traditional answer is that there is a kind of goal that is higher than both individual and spiritual interest, namely, religious interest, or the recognition of something that is worthy of worship. Is there anything holy in a spatiomaterial world like ours?

To assert that reason also has a religious interest is to hold that there is something worthy of its worship, that is, something that reason ought to recognize as holy or sacred and, thus, hold in reverence. Such an object would have to be of such exalted glory that it would inspire reason to adore it and act in a way befitting it. Such an object would be the source of a new kind of goal for reason, a goal which serves the religious interest of rational beings.

“God” is the name traditionally given for the object of the religious attitude, and the philosophical defense of religion has traditionally (in the West) been an argument for the existence of God. God is supposed to be a being of such surpassing perfection that He is worthy of our worship. But the belief in the existence of a being outside of space and time who is responsible for the natural world is supernaturalism, indeed, supernaturalism in its most familiar form, and that is what ontological philosophy gives up with its basic assumption of naturalism. Thus, if the existence of a transcendent God were what is required for reason to have a religious interest, then ontological philosophy would have to deny that reason has any such interest.

The repudiation of belief in a transcendent God has led naturalists to see religion in terms of its traditional function of justifying morality, and thus, it might be argued that ontological philosophy has already explained the religious interest by the spiritual interest of reason, as part of necessary truths of theoretical reason about what is. But if that is all there is to be said about religion, God is an illusion, and there are no religious goals for ontological reason to pursue, because ontological philosophy explains religion away. Ontological philosophy reveals that the reason for being moral derives from our spiritual interest, that is, from the function of reason as the behavior guidance system for both the spiritual animal and the individual. It would follow, then, that reason did not pursue religious goals because there is actually something worthy of worship, but simply because such beliefs were the most efficient way of guiding behavior to contribute to the natural perfection of rational beings, both individual and spiritual. It would debunk religion, because once ontological reason saw through its function, religion would no longer be needed to justify morality or to justify submitting to the group. Nor would reason be able to believe in anything like God, except, of course, as their own spiritual animal. But to hold that the interest of their own spiritual animal is what is served by the pursuit of religious goals would be to reduce religion to tribalism.

If this is how ontological philosophy must treat religion, people with a religious sensibility would surely use it as a weapon against ontological philosophy. It is ontological philosophy that believes in tribalism, for it makes the spiritual animal the source of highest goods that reason pursues. By contrast, traditional religions, despite their troubled histories, have usually thought of their goals as something more than mere tribalism, especially Christianity and Islam, with their universalistic claims. Thus, if ontological philosophy must simply dismiss religion, as most contemporary naturalists do, there are many people who will be disillusioned, if they accept it, and regret the absence of anything of truly ultimate value.

The issue is, therefore, whether there is anything in a spatiomaterial world like ours that is worthy of worship by rational beings, that is, anything that rational beings would submit to from sheer knowledge of its exalted nature.

None of the goals of reason explained thus far by ontological philosophy can be considered religious, because they are not pursued from awe at the prospect of something of extraordinary perfection and glory. Necessary goals of reason are pursued because they control conditions that affect the reproduction of the individuals or spiritual animals whose behavior reason guides. To be sure, optional goals are good for contributing to the natural (or artificial) perfection of something other than rational beings, but they are good for rational beings only because they are chosen. If ontological reason has a religious interest, therefore, there must be goals that are more valuable for reason than mere optional goals without being required in the way that necessary goals are.

The only way ontological reason could have such an interest is if there is something worthy of worship in a spatiomaterial world like ours. And as it turns out, there is. The reason is that it is possible that there is — or will be — an absolutely perfect being in a spatiomaterial world like ours. And the possibility of such a perfect being is enough, as we shall see, to make the religious attitude appropriate and to explain how reason has a religious interest its individual and spiritual interest. Ontological reason will pursue goals that are good because they contribute to the natural perfection of the world itself, and the pursuit of such religious goals will make the world even more perfect. Indeed, since ontological reason takes responsibility for doing what is good for the world, as well as the individuals and spiritual animals whose behavior it already guides, it will be the agent for the world, making the world itself a rational being. Thus, the world itself will be a perfect rational being. God is immanent, not transcendent. Though such an absolutely perfect rational being is something that will be created by reason, it is something that is worthy of worship, and the work of ontological reason in the world is to bring God into existence. That is how reason makes the world "whole."

A Perfect Being is possible in a spatiomaterial world like ours, because it could be the outcome of evolution. We have seen how the basic nature of a spatiomaterial world with a large scale structure like our own and with matter that is capable of taking on complex molecular structures like ours makes evolution by reproductive causation inevitable. Not only does evolution inevitably begin on suitable planets, but it goes through inevitable stages that lead up to rational beings like us. And as we have seen, when reason finally comes to understand how the world is whole, it discovers its own nature as a behavior guidance system for both the individual and the spiritual animal, and as I have suggested, that makes reason the most powerful being in the world. But what I want to suggest now is that, if rational beings take the perfect being that would come to exist they it were to pursue religious goals to be worthy of worship, ontological reason will eventually evolve all the perfections that have traditionally been attributed to God, insofar as that is possible in a spatiomaterial world. The evolution of ontological reason would make the world itself an absolutely perfect being, that is, God.

The personal perfection attributed to God are omniscience, omnipotence, and absolute goodness. It is possible for reason to evolve all the perfections attributed to God as a person, because a person is a rational being and theses traits are the perfection of reason as a behavior guidance system. They are, respectively, the perfection of knowing, doing, and choosing. This would be the outcome of a late phase of cultural evolution during the philosophical stage of spiritual evolution, one that starts with reason understanding of its own nature and place in the world (that is, with ontological reason) and may not be complete for some time.

Reason has three functions, let us recall, because behavior guidance systems are not mere cybernetic (or functional) systems, which use feedback to guide their behavior toward some goal, but have a function in addition to input and output, namely, choosing between incompatible goals. Even if the same input is used to select the kind of behavior and to generate it, as in animals, the selection is a third, essential sub-function of behavior guidance systems, the one that makes them the locus of evolutionary progress. It is the perfection of these three functions of behavior guidance systems that accounts for the traditional perfections: omniscience has to do with the input function, omnipotence with the output function, and absolute goodness with the function of choosing. In rational beings, the first has to do with the perfection of knowing, the second with the perfection of doing, and the third with the perfection of choosing.

Omniscience. Reason will eventually be omniscient, because the input to this behavior guidance system will be the most complete knowledge of the world possible. Reason will be able to know everything that it is possible for reason to know about the world. That is possible, given the nature of space and matter in our world, since as we know, everything in the world and everything about the world can be explained by how it is constituted by those two kinds of opposite substances. What is ontologically necessary in a spatiomaterial world like our own can be known without explaining why the basic laws of physics are true, but there is no reason to doubt that reason will eventually understand the essential natures of space and matter that make the basic laws of physics true. The knowledge of what is ontologically necessary is the framework that makes it possible to explain as completely as required any aspect of the world.

To be sure, this kind of omniscience does not include knowing all the contingent details about the world, nor does it include knowing aspects of the future that depend on its own practical reasoning. But that is the kind of omniscience one might expect of a transcendent God, not what can be expected of an immanent God. As an immanent God, reason will be able to know as much about any contingent aspect of the world as is possible for any part of a world made of space and matter. And since it will be able to figure out how efficient causes can be used to control whatever can be controlled in such a world, it will be able to discover whatever is relevant to attaining its goals. That is as much as is possible for a being in space and time.

As ontological reason begins this phase, the biggest gap in its knowledge is in astronomy and cosmology. But that does not affect the possibility of this future course of evolution, because it does not affect what reason knows about evolution and its own nature as the outcome of biological evolution. It is not necessary to know why the basic laws of physics are true to demonstrate the global regularities about change; it is only necessary to know that they are true.

Omnipotence. Reason will also be omnipotent, because the output of this behavior guidance system can control conditions in the world as well as any structural cause can in a spatiomaterial world like ours. Its omniscience includes knowledge about the means to any goals it may choose (or, at least, where to look for them and how to recognize them when they are found), and so the only limit to its power will be its ability to structure the thermodynamic flow of matter from potential energy to evenly distributed heat. But reason is responsible for guiding the behavior not only of individual rational subjects, but also spiritual animals, and thus, no structural cause can be more powerful than the spiritual structural cause of spiritual animals guided by reason, for it can coordinate the behavior of as many, independently moving animal bodies as are needed to attain the goals that it pursues.

Nothing can equal its power except another spiritual animal. But as we shall see, war would be overcome, when reason understands the nature of goodness, because of its pursuit of religious goals. Understanding the basic cause of war makes it clear what rational beings must do in order to attain their goals without resorting to war. Without such conflicts among spiritual animals, rational beings will be as powerful as possible as anything that can exist in a spatiomaterial world.

Nor is the omnipotence of such spiritual animals is merely potential. Though the parts are rational subjects who are autonomous, they will cooperate in pursuing the goals that spiritual animals pursue, if they are good. Their autonomy as rational beings is what enables them to cooperate in pursuing such goals, because it enables them to do what they believe is good.

Though reason will not be omnipotent in the way that a transcendent God is supposed to be, it will be able to attain any goal that is it possible for a part of a spatiomaterial world. And the lack of the power to do magic or create a natural world from nothing is not a real limitation, if the world is made of space and matter, because it is not ontologically possible in the first place. Omniscience has never been understood as the power to do what is impossible.

Absolute Goodness. Reason could also be absolutely good in the end. We have already seen why reason would pursue what is good for reason. All that needs to be added for reason to be a perfect being is that it also pursue what is good for the world as a whole, that is, to pursue religious goals.

Ontological reason would always pursue what is good for itself, as we have seen, because the function of choosing how to behave is served by a behavior guidance system that discovers what is good by understanding the nature of goodness. It recognizes that goodness is contributing to natural perfection, and rational imagination gives reason the ability to tell what is naturally perfect by seeing how it is a unique optimum against the background of what is possible. And since ontological reason recognizes itself as an essential part of such a natural perfection, it has sufficient reason to do what is good. It knows that there can be no reason not to do what contributes to the natural perfection of which it is part. Thus, it will do what is good for reason, that is, it will pursue goals that contribute to the natural perfection of reason itself, including both necessary and optional goals.

In order to be absolutely good in the sense implicit in traditional theology, however, reason would have to pursue goals beyond what is good for rational subjects and spiritual animals. To do God’s work is to pursue religious goals, and that means pursuing goals that are good in virtue of contributing to the natural perfection of the world itself.

That would be possible, if there are conditions that reason can bring about that would make the world itself more naturally perfect and they would not come to be in any other way. The natural perfection toward which evolution proceeds is only what is possible by reproductive causation, and natural selection is a crude instrument that takes much time and can involve much suffering. By doing what natural selection cannot do, or doing it more quickly or less wastefully, reason could make contributions to natural perfection that are not otherwise possible. It might make the structural causes bundled together in organisms or the organisms combined in ecologies even more optimal in the sense of having more power to control relevant conditions, and reason might make contributions to the natural perfection of life and the natural perfection of change by avoiding setbacks in evolutionary progress or changing their timing. Such goals would require much more detailed understanding of the evolving structures involved, but it is not impossible to make the world even more naturally perfect than it would be otherwise. Thus, reason could be good in the sense of doing what is good for the world itself, rather than just what is good for rational subjects and spiritual animals.

There are some specific goals that might be good for reason to pursue because they contribute something to the natural perfection of the world that cannot come to exist in any other way. They include the goals mentioned above as optional goals for spiritual animals. But what we need to recognize now in order to see how there could be a perfect being in a spatiomaterial world like ours is that they are also good in a different way -- not because they are chosen, but because they contribute to the natural perfection of the world. Instead of being optional, we need to suppose that reason pursues them because they are good for the world as a whole, thereby taking responsibility for making the world more perfect than it would be otherwise.

One such goal is the protection of the ecology from disruption by spiritual animals, or what is called protection of the environment. Though the capacity to survive storms, asteroids and other natural disasters may be part of the natural perfection of the ecology, protection from what spiritual animals do to it is unique, because it is an effect on the ecology that only reason can control. Furthermore, there may also be other ways in which reason might make the ecology more perfect in the sense of maximizing the use of available free energy to fuel reproductive cycles than is possible by reproductive causation. For example, it might make the ecology more perfect to tend it like a garden so that more of the available free energy is consumed.

Another such goal would be to replace the natural selection of spiritual animals by warfare with measures that would make spiritual animals just as perfect, but without the suffering involved in warfare. The only way to stop war, however, is to control population growth, since war is merely the form that the natural selection caused by reproduction takes in the case of spiritual animals. But this would not necessarily make evolution and the world more naturally perfect, unless reason also tended to spiritual animals themselves so that they become no less naturally perfect for organisms of their kind without natural selection. But if that is possible, it would surely make the world itself more perfect, because it would attain the same end with fewer and simpler means than all suffering the effects of war. War is, after all, a very wasteful means to the evolution of spiritual animals. Thus, the creation of a world order in which all spiritual animals could live in peace with one another into the indefinite future is a plausible religious goal.

Another possible religious goal would take over natural selection at the individual level as well as the social level. Natural selection at the individual level is responsible for rational subjects evolving toward the natural perfection of organisms of their kind, but insofar as it is still at work, it is also a wasteful process because of the suffering that it involves (such as individuals dying of genetic diseases). But reason could take over from natural selection as the cause of individual evolution by intervening in the germ line to correct genetic defects and to change genetic structures so that rational subjects are more powerful in attaining the goals they pursue, that is, are more naturally perfect as rational subjects.

There are surely other religious goals, including many that can be pursued on the individual level, because there are other changes that reason could bring about in the world that are neither necessary goals nor mere optional goals, but that would make the world itself more naturally perfect. And as far as spiritual animals are concerned, one of the more important religious goals will probably be the colonization of the solar system in the sense of changing conditions on them so that life can evolve on them as well as on earth.

All that is required for the outcome of evolution to have the personal perfections traditionally attributed to God is for ontological reason to pursue goals because they contribute to the natural perfection of the world itself, rather than just because they contribute to the natural perfection of reason in its role as the behavior guidance system for rational subjects and spiritual animals. That would mean that religious goals rank after the necessary goals of rational beings, yet ahead of their optional goals.

Religious goals would not be good because they are necessary goals of reason. Necessary goals of reason are those that control conditions that affect its reproduction, either as individuals or as spiritual animals. But religious goals are good because they contribute to the natural perfection, not of the individual or the spiritual animal, but the world itself. Religious goals cannot reduce to necessary goals of reason as the behavior guidance system of the world, because there are no conditions that affect the reproduction of the world itself. What makes religious goals good is simply contributing to the natural perfection of the world. But that requires seeing the world itself as a form of natural perfection. It depends on reason understanding the nature of goodness as contributing to natural perfection and seeing how what reason can do beyond merely controlling conditions that affect the reproduction of rational beings would contribute to the natural perfection of the whole.

Nor would religious goals be good as mere optional goals, either of individual subjects or spiritual animals. Optional goals are good for reason because they are already good in some way, and reason makes them good for reason by choosing them. Though religious goals are also already good, they are good in a unique way, because they contribute to the natural perfection of the world itself, not just to the natural (or artificial) perfection of a part of it that happens to catch one’s fancy. Nor are religious goals good for reason simply because reason chooses to pursue them. Rather they are good because they make the world itself naturally perfect. If religious goals are good for reason at all, they are good for reason whether or not rational beings choose to pursue them.

The religious interest, if ontological reason has such an interest, is, therefore, distinct from both necessary and optional goals. There is no reason to believe that religious goals would conflict with the necessary goals of reason, because the control of conditions affecting individual and social level reproduction would be an essential part of the natural perfection of the world. But the pursuit of religious goals would affect the pursuit of optional goals, both individual and spiritual, because reason would see their goodness as prior to optional goals. Most optional goals would be compatible with the natural perfection of the world, because optional goals also contribute to natural (or artificial) perfection in some way. But the religious interest would set priorities among optional goals, because in the context of an overall plan is to make the world itself perfect, some optional goals will contribute more to the natural perfection of the whole than others.

Ontological reason has, therefore, the potentiality of being not only omniscient and omnipotent, but also absolutely good. But if that is the future of evolution, it means that the advent of ontological philosophy is only the beginning of a phase of the philosophical stage of the gradual evolution of spiritual animals that leads to it. It will be mainly cultural evolution by rational selection, but the natural perfection for culture of this kind may not be complete until the far distant future, because there may be much for reason to do, including, perhaps, even stages in the evolution of the means it uses to attain its ends. After all, the social and political problems that it must solve are not insignificant and reason has only begun to acquire the technological control of nature that is possible. However, if ontological reason does pursue religious goals, a perfect being with all three personal perfections traditionally attributed to God would be the natural perfection toward which gradual change during that stage will proceed.

The existence of such a perfect individual and spiritual being in the world would be a form of natural perfection by our definition of “natural perfection,” because it would be the kind of optimal part-whole relation that makes the most of what exists in a spatiomaterial world like ours. For an all-knowing and all-powerful being to act for the good of the world as a whole would be for structural causes to use as much free energy as possible to control as much as possible of what happens in the world.

To pursue religious goals would make reason more powerful than simply pursuing necessary and optional goals, because it would be to set a priority among optional goals with an eye to making the world as a whole naturally perfect. Since the goals pursued would do what is required for the natural perfection of the whole, they would fit together more completely than any other set of goals, and thus, reason would be doing as much as possible to control what happens in the world. In other words, to pursue goals that conflict with religious goals could only detract from the maximum power of life, and to pursue optional goals instead of religious goals would be to have less effect on the world than is possible.

Acknowledging its religious interest would, of course, make only its planetary system naturally perfect, because given how space separates it from other planetary systems, that is the only part of the world that it can affect. But that is all that ontological reason can contribute to the natural perfection of the world as a whole, at least, for the foreseeable future.

Furthermore, it is clear that there can be no further evolutionary stage in the series that has led to ontological reason, because there is no higher level of part-whole complexity in reason as a behavior guidance system that would make it any more powerful. No higher level of forensic organization (that is, in the part-whole complexity of argument) can guide behavior any better than one in which reason understands its own nature as a system for guiding behavior that has evolved in a world of matter and space in time like our own, for there is no higher level of reflection than one that understands the wholeness of the world. Ontological philosophy is already complete in that way. Thus, once reason understands its own nature and function as a behavior guidance system, no other structure could discover what is good for individuals or spiritual animals better than it.

There is, by the way, no possibility that machines constructed as artifacts will replace multicellular animals as rational subjects, except for modifications of human biology. A machine could, perhaps, eventually be as powerful as reason, though that would require it to have rational imagination (including spatial and structural imagination as well as the capacity to reflect on itself). But such a machine would not be conscious in the way we are, unless it was constructed of neurons like our own, because the phenomenal properties whose intrinsic natures explain the subjective aspect of experience (or the fact that it is like something to perceive and think) are the intrinsic natures of the photons generated by the synchronized firing of many neurons throughout the cerebrum, like an extraordinarily complex antenna. Rational beings would not choose to replace conscious rational beings with machines that are not conscious, that is, with Zombies. They might know and control all the same conditions that make the world perfect, but without the unity of mind, there is a way in which the perfection would not exist at all.

If, therefore, ontological reason does find the prospect of such a perfect being worthy of worship and reason does evolve toward natural perfection of this kind, it will be the last stage of evolution, because it will have a kind of behavior guidance system than which none more naturally perfect can be conceived.

The kind of natural perfection that exists at this point in the evolution of philosophical spirit may be dwarfed by the perfection that eventually comes to exist, but it is clear that its basic nature permits it to acquire all the perfections that have traditionally been attributed to God as a person. Indeed, the traditional view of God can be seen as an attempt to conceive the greater perfection that is potential in rational beings before reason understands its own nature and place in the world. The traditional belief in God merely looks for God in the wrong place, as something that transcends nature, rather than as something in or about nature itself. But in order to show that what could evolve from ontological reason is a perfect being in the sense of a traditional God, it is necessary to show that this kind of perfect being also has the ontological perfections traditionally ascribed to God: being necessary, ubiquitous, and eternal.

Just as omniscience, omnipotence, and absolute goodness are simply the perfection of the three subfunctions of a behavior guidance system, so these three ontological perfections can be seen as holding of reason because it is the inevitable outcome of evolution in a world of matter and space like ours enduring through in time.

Necessary being. God as a perfect rational being would be a necessary being in a spatiomaterial world like ours, if it is the eventual outcome of evolution, because evolution is a process that inevitably gets started on suitable planets. His existence would follow from the nature of a world of matter and space in time, given that matter has the nature described by the basic laws of physics in this world and the universe has a large scale structure like our own.

If ontological reason inevitably acknowledges a religious interest, the existence of a perfect being would be a consequence of the basic nature of a spatiomaterial world like ours. Since evolution is, as we have seen, a global regularity, we might say that the necessity of a perfect rational being is shown mainly by recognizing how space is an ontological cause of evolution.

This would give God, however, the same kind of necessity that the world itself has, and there is another way in which God has traditionally been thought to be necessary. That is, substances exist necessarily because they cannot come into existence nor go out of existence as time passes, and that makes God necessary, since God is their necessary ontological effect. But the necessary existence of God has been said to derive from His being the cause of Himself, or causa sui. That would also be true of this perfect rational being, as we shall see, if ontological reason, in its practical capacity, inevitably acknowledges a religious interest.

Ubiquitous being. God is ubiquitous in a spatiomaterial world, because it is a necessary being. Reason will evolve everywhere in a spatiomaterial world with a large scale structure like our own, though its frequency depends on how often suitable planets occur. If reason must evolve into God, God will exist throughout the universe.

To be sure, scientists who understand that life could exist on other planets have set up antennas to listen for messages from more advanced life forms in the hope of solving the mysteries of the universe, and they have come up with nothing. But if ontological philosophy is right about the course of evolution, that is just what we should expect. Ontological reason will not even try to communicate with life on other planets, because it will know that intervening and solving the problems that reason confronts on other planets would only cripple the spiritual beings that are evolving there. On the other hand, if ontological reason has already evolved on distant planets, there is nothing to say to them, at least, not in that way. (There may be other ways that rational beings from different planetary systems interact. But they will be severely limited, given the distances they are separated in space and the impossibility of traveling faster than light, and they will occur at a much later point in the evolution of perfect rational beings.)

Reason is also ubiquitous in another sense, which comes from its spiritual nature as the behavior guidance system of a spiritual animal. As ontological reason evolves control over everything that happens on its planet or in its planetary system, there will be a single spiritual structural cause whose non-reproductive work dominates its entire planet, and eventually the entire planetary system where it evolves.

The ubiquity of a perfect being is a consequence of the basic nature of a spatiomaterial world like ours, but in a world that is obviously in space, evolution depends on matter being of the same kind everywhere. Hence, we might hold that its ubiquity is shown mainly by how matter is an ontological cause of evolution.

Eternal being. God is eternal in a spatiomaterial world, also because it is a necessary being. God will exist as long as the universe itself does, because He will evolve again and again throughout the existence of the world. If the universe is eternal, God will have eternal life.

Moreover, particular Gods can be eternal in their own planetary systems, because spiritual animals can exist indefinitely, even if individual rational subjects cannot, and there will always be some free energy to use as fuel for their reproductive cycles. Though God may have to inhabit only the farther reaches of the planetary system when the sun becomes a red giant and engulfs the earth. There is now about four and a half billion years to prepare. And if the red giant later becomes a white dwarf, God could move back in closer and have all the free energy required to exist indefinitely, if He so chooses.

This is to hold that the expansion of the universe does not end (as suggested in our discussion of cosmology). That is the most likely case, because as far as scientists can tell, there is not enough matter for gravitation to cause the universe to collapse back to another Big Bang, and apparently not even enough to slow the expansion to a stop asymptotically, that means the universe is eternal. However, if the Big Bang is a recurrent local process, as suggested earlier, there would be no end to the evolution of perfect rational beings.

The eternity of a perfect being is also a consequence of the basic nature of a spatiomaterial world like ours. But since it depends on how the space and matter constituting the world endure through time as substances, its eternity is shown mainly by how time is an aspect of the existential aspect of the nature of substance as substance. Thus, the eternality of God might be said to depend on how time is an ontological cause of evolution.

Except for being the creator of the world, therefore, ontological reason could eventually come to have all the perfections traditionally attributed to God, both personal and ontological perfections. It depends on whether ontological reason has a religious interest, that is, on whether it chooses to pursue religious goals in addition to its spiritual and individual goals, and that depends, in turns, on whether the prospect of the perfect being that would result is worthy of worship.

All that is required for ontological reason to evolve into a perfect being is for it to pursue goals that are good because they contribute to the natural perfection of the world itself, rather than just goals that contribute to the natural perfection of reason as the behavior guidance system for rational subjects and spiritual animals. Will ontological reason pursue religious goals?

It cannot be shown that reason ought to and will pursue religious goals in the same way that its pursuit of individual and spiritual goals, because religious goals do not contribute to the natural perfection of rational beings. Religious goals are not necessary goals of reason. They do not control conditions that affect the reproduction of rational beings at either the multicellular or social level of biological organization. And religious goals cannot be explained as optional goals, for that does not explain their special worth. Nor would optional religious goals make the existence of God inevitable.

To have a religious interest, reason would have to be the behavior guidance system for the world as a whole. But that is not a function reason could possibly have as a result of biological evolution. The pursuit of goals that contribute to the natural perfection of the world cannot evolve like another level of biological organization, beginning another stage of biological evolution, because the world itself is not a reproducing organism. That is, the world as a whole is not a primary structure generating reproductive cycles. Even something as small as the planetary system or the planet is still the whole in which evolution takes place, not a level of biological organization.

It is nevertheless possible for ontological reason to have a religious interest. The belief that rational beings ought to pursue religious goals would evolve by the rational selection of practical arguments, if what would result were perfect enough to be worthy of worship, because to beings with a faculty of rational imagination, it will be clear that accepting arguments for acknowledging a religious interest gives them the most rationally coherent world view.

As rational beings come to understand the nature of reason and its place in the world, they will see how it is possible for there to be a perfect being in a spatiomaterial world like ours, and they will recognize that its existence depends on whether they pursue religious goals, in addition to the necessary and optional goals of their and spiritual interest. If the perfect being that would result from pursuing religious goals is exalted enough that rational beings revere it and serve it from the sheer recognition of its unique natural perfection, rational beings will identify with the world itself, not just their spiritual animals or themselves as individuals. And by acting in the interest of the world as a whole, they will contribute what only reason can contribute to the natural perfection of all the organisms, to the natural perfection of the ecology, to the natural perfection of life, and to the natural perfection of evolutionary change itself. And by pursuing religious goals, a perfect being will come to exist in their planetary system.

The answer that ontological reason will give to this question is obvious to anyone who understands the situation in which reason will find itself and what is at stake in its choice. Once ontological philosophy evolves in the cultures of existing spiritual animals, rational beings will actually face this choice, and the answer will be acted out in history, determining the future course of evolution. But as rational beings who have traveled the path of this whole argument, we are in a position to know that ontological reason will see the perfect being that they can bring into existence by their actions as worth the effort.

Reason gives them more power than they need to pursue necessary goals, and among the optional goals that are open to them, some will take precedence because they contribute to the natural perfection of the whole of which they are part. By acknowledging that it has a religious interest, reason will change in the direction of maximum holistic power, because when the world as a whole is naturally perfect, as much as possible of what happens in its planetary system will be controlled using the available free energy as efficiently as possible. Ontological reason will, therefore, choose to pursue religious goals.

This choice is similar to another stage of evolution, because an entire new range of conditions come under the control of living organisms. In this case, those conditions are not relevant in the sense of affecting the reproduction of an organism with a higher level of part-whole complexity. But the conditions that are controlled are on a higher level of part-whole complexity than the necessary and optional goals of rational beings, because they contribute to the natural perfection of the world itself (that is, at the scale of its planetary system, the part of the world it can affect). Thus, what makes it good to pursue religious goals is the same thing that makes a higher level of part-whole complexity in evolving organisms good: it contributes to the natural perfection of life.

Though the autonomy of reason makes it possible to pursue any goals that are good, the pursuit of religious goals maximizes the holistic power of reason, because, as we have seen, they are aimed at controlling all those conditions that make the biggest difference in the perfection of the world as a whole. There is no other set of goals that would enable reason to control more of what happens in the world, and thus, religious goals would contribute to the natural perfection of reason itself.

The self-creation of God. For rational beings to choose to pursue religious goals, however, is for ontological reason to choose to transform itself into God. It is the prospect of a perfect being inspires them to make this choice, but the perfect being in prospect comes from reason itself, and thus, it comes from reason choosing to do what is good because it contributes to the natural perfection of the world as a whole. But since that is to act as the perfect being that ontological reason intends to bring into existence, God already exists in those actions. Thus, the belief in God is a self-fulfilling belief. God creates Himself. And God continues to create Himself in all the actions that are done in the interest of the world itself.

Even the immanent God in a spatiomaterial world like ours would be causa sui. God would create Himself, because ontological reason makes itself into God by acting in the name of God.

The world as a rational being. To pursue religious goals is, however, to act for the good of the world as a whole, and thus, it is for the world itself to be a rational being. That is, ontological reason takes up the function of being the behavior guidance system for the world itself, and thus, it does for the world what it does for the spiritual animal and for the individual rational subject.

To be sure, the world does not become a rational being because it is a reproducing organism like individuals and spiritual animals, imposing natural selection on themselves by their own reproduction. But that is merely to say that the world does become a rational being as a direct result of natural selection, or biological reproductive causation. It is due, instead, to the cultural evolution of practical arguments by rational selection. The world acquires the power of reason to do what contributes to the natural perfection of the world itself, because the kind of natural perfection that inevitably comes to exist within it includes rational beings who are able to understand how the world is whole, who recognize themselves as a necessary consequence of its nature, and who see how and why it is good for them to act in the interest of the world as a whole.

The world as a perfect rational being. Since this outcome is inevitable, however, the world is not only a rational being, but a perfect rational being. The nature of a spatiomaterial world like ours makes it inevitable that evolution will begin, because as we have seen, the effect of the cycle of night and day on the kinds of molecules that exist on suitable planets is the existence of reproductive cycles, which impose natural selection on themselves. The course of evolution is inevitable, because, as we have seen, it involves an inevitable series of evolutionary stages, each caused by a higher level of part-whole complexity in the evolving structures of reproductive organisms (taken broadly to include arguments that reproduce within spiritual animals as primary structures). We have seen how the inevitable outcome is ontological reason, that is, rational beings who understand how the world is whole, who recognize themselves as the inevitable outcome of evolution, and who inevitably choose to pursue religious goals because they see how it would make the world itself perfect. With reason acting as a behavior guidance system in its interest, the world is a rational being. But since it is an inevitable consequence of the nature of a spatiomaterial world like ours, it is an expression of the essential nature of what exists. The nature of the world is revealed, not only in the basic nature of what exists, the essential natures of space and matter in time and how they exist together as a world, but also in the nature of what inevitably comes to exist from it. Thus, it turns out that the world itself is perfect. And since the world is inevitably a rational being, the world is a perfect rational being.

What we have been calling “natural perfection” are part-whole relations that are optimal because of the basic nature of the world, but now we find that that nature not only sets the standard of perfection, but also measures up to it in the most complete way. In general, the perfect makes the most out of the least. But the standard of perfection appropriate to nature is fixed by the second law of thermodynamics, because that makes it possible for structural causes to use the thermodynamic flow of potential energy towards evenly distributed heat to make things happen that would not otherwise happen. Judged according to this standard, part-whole relations are optimal when structural causes are combined in such a way that they use the available free energy as efficiently as possible to control as much of what happens in the world as possible. That is how to make the most out of what exists in a world constituted by space and matter enduring through time. And now we find that the basic nature of the world not only sets the standard of natural perfection, but also makes it inevitable that what happens in the world eventually measures up to that standard as completely as possible. And it is more complete than what is possible by natural selection alone, because it uses a behavior guidance system that guides behavior to what is good by recognizing how and why the good is good, even when it does not control conditions that affect its own reproduction.

The world as God. Since the world, because of its very nature, inevitably becomes a perfect rational being, the world itself is God. As ontological reason acknowledges its religious interest, it takes responsibility for the world as a whole, doing what ought to be done because it contributes to the natural perfection of the world as a whole. That is the work of ontological reason in the world, to act for the good of the world itself.

Thus, it will be possible for ontological reason to answer G. E. Moore’s doubts about the possibility of any such naturalistic explanation of the goodness of religious goals in the same way as it does his doubts about the goodness of other goals. To a rational subject who understands her nature as a rational subject and her place in the natural world, including her identification with the world as much as with her spiritual animal or her individual Self, it will simply does not make sense to ask, But is contributing to the natural perfection of the world good? She will know that it is contributing to her own natural perfection and, thus, that it is good in the same way as her other goals are good. Religious self interest will, therefore, take its place, along with spiritual self interest and individual self interest, as what determines the goals she will pursue. That is, they all contribute to the natural perfection of reason.

The pursuit of religious goals is also the wisdom that Socrates was seeking, because this ontological explanation of the nature of goodness explains why religious goals are good for the rational subject in a way that will make him religious. The pursuit of religious goals is good for him as a rational being, because it contributes to his own natural perfection.

An act of free will. God comes into existence from an act of self-creation, and though it is inevitable, it is an act of free will. As we have seen, free will is autonomy, or the power that reason gives individual subjects to do the good simply because they know that it is good. The choice of ontological reason to pursue religious goals is autonomous in that sense, because it comes from the knowledge that it is good for rational beings to contribute what only reason can contribute to the natural perfection of the world as a whole. It is inevitable, but only because it really is good and reason understands things so completely that it knows that it is good.

God’s act of self-creation within a spatiomaterial world is free in the same sense that Aquinas had in mind when he argued that God’s choice to create the natural world was free. Aquinas was, of course, talking about the traditional, transcendent God of epistemological philosophy. But he wanted to deny that the existence of the natural world is a necessary consequence of God’s nature, because that would mean that it was not an act of free will. What Aquinas meant can be expressed, I believe, by saying that God created the world because He understood the nature of goodness. Because that understanding enabled Him to see that it would be good to create the world, He chose to create it because it is good. In the same sense, it is by an act of free will that God creates Himself in a spatiomaterial world: ontological reason understands the nature of goodness and, by seeing that it would be good for God to exist, chooses to create God because it is good.

That is also the sense in which practical reason, according to ontological philosophy, cannot be reduced to theoretical reason. Since ontological reason’s choice to pursue religious goals is inevitable, the existence of God is among the necessary truths about What is that reason can know by theoretical reason, that is, in reason’s capacity as knower of the true. But that does not mean that What is includes everything that holds necessarily for reason because spatiomaterialism is the best ontological explanation of the world, because What is is, in part, a result of what ontological reason does. Reason creates God, that is, transforms itself into God by acknowledging that is has a religious self interest, as well as a spiritual and individual self interest. Doing cannot, therefore, be eliminated in favor of knowing. It is a product of ontological reason in its practical capacity.

In explaining what happens before the evolution of ontological philosophy, reason can be treated like any other evolving structure. But when ontological philosophy evolves, that explanation becomes part of what is evolving, and as ontological reason, it is the agent whose practical reasoning brings about the subsequent course of evolution. Ontological reason cannot sit back and simply contemplate the existence of God, because the coming into existence of a perfect rational being is the doing of reason. And it does what it does, not because it recognizes its inevitability, but because what it does is guided by What ought to be. In the end, therefore, “ought” implies “is.”

To be sure, the content of practical reason, including all the goals that ought to be pursued, coincides, in part, with the content of theoretical reason. Its necessary truths about What is include what reason does inevitably in the world. But the diagram of the whole argument of ontological philosophy does not misrepresent what holds necessarily for reason by separating the conclusion about What ought to be from the conclusions about What is, because for reason, there is a difference between knowing and doing.

The difference between theoretical and practical reason is nearly as basic to reason as the difference between the ontological foundation and the necessary truths that follow from it, which is represented in a similarly fundamental way in the diagram of the whole argument. In that case too, the content of necessary truths coincides with part of the content of the ontological foundation, because the necessary truths, being truths that follow from it, are implicit in it. But the distinction is important for reason, because there is a difference between what reason knows about the world empirically (by an inference to the best ontological explanation of the world) and what reason knows about the world prior to discovering what happens in the world by experience. If there were no difference between ontologically necessary truths (including conditionally ontologically necessary truths) and ordinary empirical knowledge, ontology would not be a new way of doing philosophy.

God is known first of all, therefore, as an intention of practical reason, as the goal of ontological reason’s own plan of individual and social level behavior in the world. That is the sense in which practical reason is not reducible to theoretical reason. The creation of God is the work of ontological reason in the world.

Ontological philosophy entails, as we have seen, the existence of an immanent God. But believers in a traditional religion, especially those who believe in a transcendent God, are likely to be skeptical about the world itself being sufficiently perfect to be worthy of worship. One way to quell such doubts is to show that all the reasons for holding that a transcendent God is worthy of worship are reasons that also hold for the immanent God of ontological philosophy. That is possible in this case because the points of disagreement about the nature of God are not relevant to God's worthiness of worship.

In what follows, I will argue that the immanent God entailed by spatiomaterialism is worthy of worship by arguing that it has all the traits that are thought to make the traditional God of epistemological philosophy worthy of worship. And since it will also solve the theoretical problems that philosophical theology has encountered trying to think about God coherently, it may even convince traditional theists that such an immanent God is what they have actually been believing in.

This is to give an ontological interpretation of Christianity, but a similar argument can be constructed, I believe, for the beliefs of all the other traditional religions. In their case as well, what makes God worthy of worship is also implicit in this immanent God, as would be shown by giving an ontological interpretation of them. That is, at least, what ontological philosophy would expect, since traditional religions are trying to grasp something about the world that really is holy, but as through a glass darkly. However, only Christian theology will be discussed in the following argument. Christianity is the religion in which epistemological philosophy was historically developed most fully, and though this critique of Christian theology will suggest how it would work in other traditional religious, I must leave that to others.

Let me emphasize, however, that what I say here about Christianity is not the result of a conversion experience on my part. I have not been reborn by accepting Jesus as my savior. I long ago abandoned the faith of my parents and left the church, because I could not believe that naturalism is false, at least, not in the way required to believe in a transcendent God. Nor could I believe that one discovers the truth about such matters by an act of faith. However, in the long process of working out this ontological explanation of the wholeness of the world, I have become increasingly sympathetic with religion, for I have slowly discovered that the wholeness of the world entails the existence of a perfect being -- one that can be recognized as the God referred to by Christian theology, because it has all the traits that make the transcendent God of traditional Christianity worthy of worship. Thus, all that Christians would have to give up in order to recognize that ontological philosophy confirms what they want to believe about the world are metaphysical beliefs that cause theoretical problems — except possibly for the belief in personal immortality, and I will argue that they would not really want that, if they understood the nature of existence.

Some might, therefore, claim that Jesus is a prophet of ontological philosophy. But Jesus is not what leads reason to recognize the existence of God. The path that leads to the explanation of the wholeness of the world in its most complete sense is the path that Socrates was on. And that is a path that began when the Pre-Socratic philosophers gave up religious explanations of the world in favor of an ontological explanation. Indeed, ontological philosophy is, I believe, the wisdom that Socrates was seeking when he distinguished himself from the sophists as a philosopher, that is, a lover of wisdom. It is the knowledge of the nature of the world, including the nature of goodness, that makes rational beings choose goals that are good because they are good. That is, knowledge is virtue! The Socratic principle is true. Thus, although the end of the road of reason is, as I will argue, what Jesus was talking about, it is only reason, not faith (and certainly not force), that can lead us there.

The doctrines of Christian theology. What I take to be Christian theology can be summed up as five doctrines. They are mainly the doctrines that emerged in the medieval period. Many variations on them and interpretations of them have been developed since then, including some that take Christianity to be merely a mythical representation of a moral code. But the more traditional Christian beliefs about the nature of God and the meaning of life bring out more clearly what is true in Christianity, according to this ontological theology.

God’s transcendence of the natural world. Christians (and Jews) have to believe that God transcends the natural world, because He is supposed to have created it by an act of free will. The natural world includes everything in space and time, and thus, unless God were a substance that exists outside space and time, He could not have created it.

The trinity. The most distinctive tenet of Christian theology is, perhaps, the doctrine of the trinity, that God is actually three persons: the Father, the Son and the Holy Spirit. The Father is the creator of the natural world, who for some reason put human beings on earth. The Son is the incarnation of God on earth whose sacrifice was meant to earn the forgiveness of our sins so that believing that Jesus is Christ would give us salvation from sin and eternal bliss. Thus, God had to be at least two persons. But Christians also believe that God acts in the world by way of the Holy Spirit as well, and that is God as a third person. Thus, despite being a single substance, God is supposed to be three persons, the Father, the Son and the Holy Spirit (and theologians have struggled vainly to explain how that is possible).

Original sin. The source of evil in the world is supposed to be a result of original sin. In the beginning, when Adam and Eve were in the Garden of Eden, God forbad them to eat the fruit of the tree of the knowledge of good and evil. But Adam and Eve had free will, and being persuaded by a serpent, representing Satan (an angel in rebellion against God), they ate the apple, thereby defying God’s command. That was the original sin. As punishment, God banished Adam and Eve from the Garden of Eden, and after the fall, they and all their children and children's children became mortal beings. They were ashamed of their bodies; they had to labor in order to live; they were both agents and patients of such suffering as war; and they who had to suffer famine and disease, as well as death. Thus, the evil in the world is supposed to come from an act of free will in defiance of God’s command. And their offspring would always be tempted to choose evil and sin, because Adam and Eve had eaten the fruit of the tree of the knowledge of good and evil.

The gospel. Christians believe that the “good news” brought by Jesus as the Christ, or savior, was that God had forgiven our sins, including our original sin. It was possible, therefore, with the grace of God, to avoid sin. This meant, according to Jesus, that the kingdom of God is at hand and, since it would thereafter be possible to avoid the evils that had plagued the descendants of Adam and Eve, we would live in heaven forever. All that is required for this to happen is that that we believe in Jesus as our savior, that we love God, and that we love our neighbors as ourselves, that is, a conversion to Christianity. Though only faith in Christ is required for salvation from sin, it is the struggle to overcome sin and evil that is the basic meaning of life, according to Christianity.

Immortality. When Jesus was crucified, God sacrificed his only Son, and the divinity of Jesus was shown by his resurrection from the dead after three days and his bodily ascension into Heaven some while later, joining his Father. The reward of believing in Christ is salvation from sin, and according to the traditional Christian belief, that means having eternal life in the presence of God, that is, in heaven. Thus, Christianity holds that everyone has an immortal soul in the sense that each person is a substance that lives after the death of their bodies on earth. For the saved, that means living eternally in the presence of God, and heaven is thought to transcend the natural world, just as God Himself does. But the eternal fate of our souls depends on our free will, that is, whether we choose to believe in Christ. Those who do not are not saved, and their immortal souls spend eternity in Hell, deprived of God’s presence. Thus, what is at stake in the choice one makes about how to live one’s life is the fate of one’s eternal soul.

An ontological interpretation of Christian doctrines. God is immanent, according to ontological philosophy, because it implies that the world itself is a perfect being. The basic nature of a spatiomaterial world like ours gives rise to progressive evolution, and that eventually leads to the existence of perfect rational beings, who act for the good of the world as a whole. That is our foundation for explaining what is true and what is false in the doctrines of Christian theism. Insofar as the beliefs that make the Christian transcendent God worthy of worship can be explained by our immanent God, Christians must admit that this pantheistic God is also worthy of their worship. Nor can Christians deny that this immanent God is worthy of their worship, if the ways in which it contradicts traditional theism are not what make their transcendent God worthy of worship.

This way of showing that the pantheistic God of ontological philosophy is worthy of worship is, of course, an ad hominum argument for Christians. It will not persuade everyone, because non-Christians may deny that even the Christian God is worthy of worship. But that is not necessary, since we have already seen that ontological reason acknowledge a religious reason. But it will show how ontological reason can be seen as taking up where Christianity (and religion generally) leaves off, enabling rational beings to have from reason something more than what Christians had to take on faith.

I will take up each of the traditional doctrines of Christianity and offer what seems to me to be the most sympathetic interpretation of them from the standpoint of ontological philosophy. But I will leave the first doctrine, about the transcendence of God, to the last.

The central doctrine from which Christianity derives its name is the belief that Jesus was Christ, the Son of God. The doctrine of the incarnation of God is problematic, because it means that one and the same substances that created the natural world must also be particular substance in that world. It is hard to explain how a single substance can be two such different persons, but if God must be two persons, it is not much more implausible to suppose that there are three altogether. Indeed, Christianity assumes that, in addition to the transcendent Father and bodily Son, God exists in a third form, as the Holy Spirit. The Holy Spirit is supposed to do God’s work on earth. Thus, the doctrine of the trinity holds that, even though God is a single substance, He is three different persons: the Father, who created the natural world and sent his Son to save us; the Son, who brought the father's word to the world; and the Holy Spirit, who does God's work.

It seems to some that the doctrine of the trinity is self-contradictory, and though believers are willing to believe that it is just another mystery that lies beyond the understanding of finite rational beings, the immanent God entailed by spatiomaterialism suggests a solution to that mystery. It is possible for finite rational beings to understand how the three persons of God are a single substance, because in a spatiomaterial world like our own, that substance could be the whole world.

It is possible to explain what is meant by "God, the Father,"for that could be the basic nature of the world. That is what is responsible for the existence of beings like us in the world, for it is the ontological cause of the evolutionary process by which a rational beings come to exist in the world. Since what evolves in the culture of philosophical spiritual animals is the knowledge that provides makes heaven on earth possible. The word of God can be seen as what is spoken by rational subjects with ontological reason, and thus, they can be seen as what is meant by "God as the Son." That is, the individual's knowledge of the truth about the wholeness of the world, including the nature of goodness, is the knowledge of the word of the Father, which Christ was supposed to have. And the "Holy Spirit" refers to the spiritual animal that exists when the word of the Father is known, because when ontological philosophy evolves, reason understands the wholeness of the world, and by acknowledging its religious interest, ontological reason does God’s work, the work of becoming a perfect rational being, that is, God’s self-creation. Thus, all three persons of God can be seen as aspects of the same perfect substance, namely, the world as a whole.

It might seem that, although ontological philosophy can explain how a single substance can have all three aspects, it does not quite explain the doctrine of the Trinity, because it does not show that they are all persons. Individuals are clearly persons, because they are rational beings. And since spiritual animals are rational beings, they can also be called persons. But even if the basic nature of a spatiomaterial world like ours is perfect in the sense of giving rise to natural perfection, the world as a whole is hardly a person.

This objection overlooks, however, a consequence of ontological reason acting in the interest of the world as a whole. When reason takes on the function of being the behavior guidance system for the world itself, the world itself becomes a rational being. And since rational beings are persons, the world is a person.

In other words, the reason that there are three persons of God is that ontological reason has three practical interests, individual, spiritual and religious.

These three rational beings are a single substance in the sense that they are all constituted by space and matter, the substances whose existence explains the existence of everything else in the world. The difference between them is that they are rational beings on different levels of part-whole complexity in space. The Son refers to each of the rational subjects who are parts of spiritual animals after ontological reason evolves. The Holy Spirit includes the spiritual animal (or all the spiritual animals) whose behavior is guided by ontological reason to do what is good for the world as a whole. And the Father is the whole world to whose natural perfection religious goals contribute.

To be sure, what is affected by the activities of the Son and the Holy Spirit may extend no farther than their own planetary system. But that does not mean that it is not a contribution to the natural perfection of the world as a whole. It does make the whole world more perfect than it would be without ontological reason, and it happens throughout the universe, since because perfect rational beings evolve on every suitable planetary system.

The most telling objection to traditional pantheism is that it is incompatible with God being a person, but that does not tell against the kind of pantheism entailed by ontological philosophy.

The God of ontological theology is a person, because He has the nature of a rational being. Even though ontological philosophy takes the world as a whole to be God, that is compatible with God being a person, because the world itself has behavior that is guided to do what is good for it by rational subjects who do what as good for the world as part of their self interest. That is not incompatible with God being a rational agent that also has an individual and spiritual self interest. Indeed, even if Christianity had not believed in the Trinity, ontological philosophy would still have had to recognize something surprisingly similar to it, because a spatiomaterial world like ours necessarily has rational subjects with an individual, spiritual and rational self interest.

It is even possible for ontological philosophy to confirm the traditional Christian view of original sin as the source of evil in the world and, thereby, understand its view of the meaning of life. But since its interpretation of that doctrine locates original sin in the larger context of evolution, it avoids the problems that the existence of evil has posed for traditional theism.

Original sin can be explained as war. Accordingly, the Garden of Eden would represent the innocent life of higher primates or first hominids. War was an inevitable evil, because this means that the serpent that talked Adam and Eve into disobeying God's command was the evolution of natural sentences (rather than an angel rebelling against God, which is, in any case, difficult to reconcile with God's omnipotence. The use of language made war a possible means for groups of hominids to overcome the scarcity caused by the reproduction of spiritual animals, and it can even be seen as a "violation" of God's command in the sense that groups of nonlinguistic animals are apparently unable to evolve the behavior of killing other groups of animals from their own species in order to acquire food. But the evolution of war in spiritual animals was inevitable, and the advent of war can be seen as banishing them from the Garden of Eden, for it forced them to live in a dangerous world indeed. To fight wars was, furthermore, to eat the fruit of the tree of the knowledge of good and evil, because as we have seen, the group-level selection pressure imposed by warfare led to the evolution of reason. Though the original function of reason was to choose more reliably between war and peace, that became, as reason evolved, the more general choice between good and evil, because reason had to enable members of spiritual animals to live at peace with one another. Evil is what is at stake in morality, because individuals had the option of intentionally harming others as a means to their ends, and from their adaptation to war, they even had desires that made it possible to enjoy killing other members of their own species. Reason discovered moral rules that limited the pursuit of their interests, and it gave them autonomy, or free will, that is, the ability to resist even the strongest animal desire and do what they believe is good and right. But it was an imperfect mechanism, and moral evil was an inevitable apart of the world. Thus, their fate was to be both the agent and patient of harm done intentionally, both war and moral trespasses against other individuals — not to mention bearing the burden of the labor involved in the evolution spiritual animals.

Ontological philosophy can, therefore, confirm, in a way, the traditional doctrine of original sin. But what is more, ontological theology solves other problems that Christian theology faces about the nature of evil.

One problem with the doctrine of original sin is the inability to explain why God would create beings with a free will who He knew would disobey Him. That is supposed to be part of God’s mysterious purpose and, thus, beyond human understanding. And even though Christians believe that God ultimately would forgive them their original sin, making salvation possible, there is no explanation why, generation after generation, the fate of their immortal souls should depend on the choices they make on earth. That was still part of the mystery.

Another problem is the fact that evil exists at all, for that argues against the existence of a supernatural God. That is the so-called “problem of evil.” If God created a world that contains evil, then either (1) God must not be absolutely good, (2) God must not be all-knowing, or (3) God must not be all-powerful. God must lack at least one of these three traditional perfections. There is some plausibility to the claim that the existence of moral evil is necessary on the grounds that evil will be done as long as there are beings who have both free will and the capacity to do evil, and that cannot be avoided, if the existence of human beings in a world like our serves some higher purpose that God in creating the natural world in the first place. But it is still a mystery why the existence of finite beings with free will is good or makes the natural world good. And even if there is some such explanation of moral evil, there is still no explanation why natural evil, such as famine, disease, and earthquakes, should be part of God's plan.

Ontological theology, however, solves both these problems. Evil does not show that an immanent God must lack any of the personal perfections of God, because the world as a perfect rational being will do everything that can be done to avoid evil in the world. It is just that the evil that occurs in evolution is not something that can be avoided, because that is how perfect rational beings come to exist.

Ontological philosophy also explains, therefore, why there are beings with free will who must struggle against original sin in order to avoid evil. War and the evolution of reason is an inevitable stage in the evolution of spiritual animals. Furthermore, this explanation reveals why the existence of such rational beings is good: it makes a necessary contribution to the natural perfection of life, the natural perfection of evolutionary change, and in the end, to the evolution of perfect rational beings in the world. No being who lacks the power to do evil can be an all-powerful being. The progressiveness of evolution, therefore, compensates for the moral evil that exists in the world.

Finally, even the natural evil that exists in the world is compensated. Nothing can be good without evil, because evil is necessary for evolution. The scarcity caused as reproductive cycles multiply is evil, by our definition of "good", because it detracts from the natural perfection of which it is part. But such evil is compensated. There would be no natural perfection and, thus, no goodness without it, because that is how reproductive cycles impose natural selection on themselves and propel evolution along. Likewise, since disease is a necessary consequence of the evolution of organisms at lower levels of biological organization, it makes a contribution to the natural perfection of the ecology. Death is a necessary part of the structure of the reproductive cycles of multicellular animals and, thus, of subsequent evolution. And even natural catastrophes, like the impact of asteroids, play a necessary role, because they alter conditions so radically that inherently more powerful organisms can replace inherently less powerful incumbents in ecological niches. That is, after all, how mammals replaced dinosaurs in the most energy rich ecological niches some 65 million years ago.

Not only does the belief in an immanent God make it possible to see a truth in the Christian belief about the meaning of life -- that it is the struggle for salvation from original sin -- but it can also be seen as confirming the “glad tidings” taught by Jesus about eventual success.

Grace. The “good news” was that God has forgiven us our sins, and according to ontological philosophy, Christians are right to believe that salvation from original sin is possible. Indeed, it can even be said to depend on the grace of God, although the grace of God must be understood, not as a gift of forgiveness of sin by a transcendent God, but rather as the fact that the nature of the world makes perfection possible for spiritual animals and their members. It is possible in the end to control population growth and arrange human affairs so that wars do not occur and human beings are not even tempted to do evil to one another. Indeed, that is part of the natural perfection of the world itself that ontological reason undertakes to bring about when it acknowledges its religious interest.

Heaven. Salvation from sin means that the kingdom of God is at hand and that we shall have eternal life in heaven. What Jesus saw was the kind of natural perfection that is possible for beings like us, who can see into one another minds and act together in pursuing goals. Jesus was right to insist that what it involves is loving God and loving one’s neighbor, for that is what is involved in pursuing religious goals. But according to ontological theology, heaven will be at hand only when ontological reason acknowledges its religious interest and pursues goals because they make the world as a whole naturally perfect. And in that heaven, there will be eternal life. Once a perfect rational being exists, reason can go on pursuing goals that are in individual, spiritual and religious interest forever, because spiritual animals can live as long as the world.

Belief in Christ. Salvation is supposed to be the result of believing in Christ, that is, believing that He is the Son of god and following his commandments to love God and our neighbors as ourselves. But Jesus was mistaken to believe that all that heaven requires is a change of heart, a conversion to Christianity. Heaven will exist only when original sin is overcome, and according to this naturalistic ontological interpretation of his gospel, that requires the labor of reason, though cultural evolution and history. When Jesus taught his vision of perfection, there was still much more for reason to learn before it could understand the wholeness of the world. And once that is understood, reason still must do God’s work by, among other things, controlling the causes of war and controlling the causes of the moral evil that individuals do to one another.

On this interpretation of Christian theology, therefore, the significance of the belief that Christ is God become man is that it is possible for rational subjects like us to understand the word of God and create heaven on earth. That is, Jesus represents the fate of rational subjects generally. It happens during the philosophical stage of spiritual evolution when reason finally understands how the world is whole, sees itself as the inevitable outcome of evolution, and by understanding the nature of goodness, understands how and why it is good for reason to pursue goals that are good for the world as a whole. As ontological reason acknowledges its religious interest and does the work of creating God, original sin is overcome and eternal life in heaven begins.

In sum, salvation depends, not on faith, but on reason. The incarnation of God is that rational subjects have the kind of understanding that God was supposed to have when he created the natural world. It is, in effect, to understand God's purpose in creating the world. And that is what makes it possible to create heaven on Earth.

The promise of eternal life in the presence of God may seem to be where ontological philosophy fails to explain Christian theology, because it must deny that rational subjects have immortal souls. The immortal soul is supposed to be a substance that continues to endure though time after the body decays. But except for the matter and space that constituted the body, there is no such substance, and thus, there can be no life after death. That does not mean, however, that ontological philosophy must deny the promise of eternal life in heaven.

Though they are not immortal as individuals, rational beings can and will be immortal as a spiritual animal. Spiritual animals can be immortal, because they do not reproduce by the sexual mixing of parts of their structures, like eukaryotes. They reproduce by division, like prokaryotes. The same spiritual animal can continue to exist indefinitely, and that is what begins when reason evolves into God. The perfect rational being that comes to exist on earth as the outcome of evolution is the existence of God in the world, and that is eternal life in heaven. The immortality of the spiritual animal is a kind of immortality for the rational subject, because the spiritual animal is an aspect of the self in whose interest the rational subject acts. Indeed, the world itself as a whole is an aspect of the self in whose interest the rational subject acts, once the world becomes a perfect rational being in that sense. The immortality of the spiritual animal and the world are way in which the self live on after the death of the individual body.

To be sure, the individual must eventually die. Since rational subjects are multicellular animals, they cannot live without going through reproductive cycles in which they are born and die. But the life of the rational subject as an individual multicellular animal is not the only life she has, because she is, as a rational being with ontological reason, the agent who guides the behavior of her spiritual animal and even the world itself, not just her own body. That is, the self in whose interest she acts is not just the individual, but also the spiritual animal and the world, and her spiritual and divine self are immortal. That is how the rational subject has life after death.

Ontological philosophy does imply, nevertheless, that rational subjects do not continue to live as individuals after the death of the body, and this is not what Christians believe about how their souls are immortal. It may, however, be closer to what Jesus himself actually meant, because as a Jew, the kind of salvation that he probably believed the Messiah would bring was heaven on Earth.

The belief that salvation takes the form of immortal souls in an otherworldly heaven could have been what the earliest followers of Jesus came to believe in order to avoid losing their faith in Jesus’ message when he was crucified. If they expected the kingdom of God to begin immediately on earth, his death would suggest that Jesus was simply mistaken. But it was possible to continue to believe that Jesus' followers would have eternal life in heaven, even though it did not happen on earth, if it meant having immortal souls that live in the presence of God in a transcendent realm. That would be the significance of the resurrection and ascension, and it would be another distortion caused by the belief in a transcendent God. (For a defense of such a view, see Thomas Sheehan, 1986.)

Though ontological philosophy must deny that rational subjects have immortal lives as individuals, that does not mean that its immanent God is any less worthy of worship than the traditional Christian God. It merely reflects the difference in what rational beings really want that comes from understanding the nature of existence.

In a world constituted by space and matter, the immortality of bodily existence is not a good thing. Rational subjects who understand their nature ontologically as inevitable products of evolution by reproductive causation will not want to be immortal as individual multicellular animals. They will recognize that the desire to have an immortal soul is a form of narcissism, an unhealthy kind of "selfishness."

It is possible to extend lives, and that will be done, because it is good. Life is not currently long enough to make the most of it. And it will probably also be possible to make the body immortal in the sense that it will not die of old age or disease, but only by accident. But it would not be good to make the body immortal, because the natural perfection of the rational subject as an individual requires a temporal limit to life.

The life of an individual is a process of growth. She starts out as a baby, only later acquiring the capacity for reflection, and she goes through a process of development and growth that continues throughout life, until death. What makes the maximum holistic power of the multicellular animal holistic is that it controls all the conditions that affect reproduction over the whole cycle. That is the way to make the most of the least in the case of the individual animal. The parts that fit together as such an optimal whole are mainly the rational actions that make up the life as a four-dimensional object, and the individual gains power to control relevant conditions in the process of growing older. One acquires practical wisdom as time is running out. The self one constructs is like a painting, as I suggested earlier, that is painted from left to right on the canvas, trying to make the most of every part of the life. That each moment make its own essential contribution to the perfection of the whole -- that is, that it not be redundant -- is a essential aspect of the structure of the natural perfection of the individual animal. If life did not terminate at some point, there would be no whole of which the parts are all parts and thus no possibility of a natural perfection about it.

Or to put it negatively, growth is such an essential part of the structure of the natural perfection of individual life that the worst hell that a reflective subject with ontological reason could imagine is to have grown as much as possible for beings of her kind and yet be unable to die. Even if she were in perfect health and in possession of her faculties, it would become boring to go on living, because in a world made of space and matter, there is a limit to how much an rational subject can do and learn and enjoy. After she had passed that limit far enough, it would be torture to wake up each day and know that it would just another repetition of something already experienced many times before. Fortunately, such a condition is not possible for rational subjects with behavior guidance systems based on brains.

God’s transcendence of the natural world. Christians believe that God transcends the natural world, and that seems to be an aspect of traditional theology that ontological philosophy must deny. But transcendence is not relevant to God's worthiness of worship, for it is simply what Christians had to believe in order to believe that God is responsible for their own existence and the source of purpose in the world. Ontological philosophy makes it possible to see God as the creator in the latter sense without transcending the natural world.

Christian believe that God created the natural world out of nothing. It is the role of God as the Father to call into existence by an act of will the natural world and the teleological order it involves, including human beings. But if God as the Father is the basic nature of a spatiomaterial world like ours, as ontological philosophy implies, God is still the source of human beings and all the purpose in the world. That is, God is still the creator of the natural world in the relevant sense, and thus, such an immanent God is no less worthy of worship than the transcendent God of traditional Christian theology.

An immanent God cannot create the world as act of will. But the world can, and does, by the very nature of what exists in it, give rise to the existence of rational beings like us. It is our “creator” in the sense of being the source of our existence. To be sure, since we are a necessary consequence of its nature, we are not something done from the knowledge of the nature of goodness, that is, created as an act of free will. But the nature of the world gives rise to us as part of the process by which it gives rise to natural perfection and a real difference between good and bad in the world. Thus, even though God is not a substance existing outside space and time that gives rise to a world of objects in space that change through time, God turns out to be the cause of our human world and the source of real difference between good and bad. Hence, an immanent God is no less awesome. Nor is such an immanent God any less beneficent, that is, “good-doing,” though, of course, He cannot be benevolent, that is, “good-willing,” except through God’s self creation as a perfect rational being.

Simply being immanent does not make God any less a perfect rational being than a transcendent God. To be sure, an immanent God does not know as much and is not as powerful as it seems a transcendent God would be. But that does not make an immanent God any less worthy of worship, because it does not imply that an immanent God is inferior to a transcendent God. It is merely a difference is the conception of perfection that comes from one's conception of the nature of existence. The kind of perfect knowledge and power that is conceivable in a substance that exists outside space and time is different from the kind of perfect knowledge and power that is conceivable in something made of space and matter in time. But that does not show that one is better than the other, for it is just a question of which ontology is true of the actual world.

Finally, if there is a difference in perfection, there is one way in which an immanent God is more perfect than a transcendent God. Both are alike in having something permanent and unchanging about them. A transcendent God is unchanging because He outside of time, whereas an immanent God is unchanging because He is constituted by substances that endure through time with the same essential natures and they inevitably give rise to perfect rational beings. But since a transcendent God is outside time, He cannot change at all. Thus, He lacks at least one perfection that an immanent God can have, namely, the natural perfection of change itself. When evolution is change in the direction of natural perfection, as we have seen, each moment in the existence of the world makes a unique and necessary contribution to the existence of a perfect rational being in the world. Time is another way in which parts may be combined optimally as a whole, and a transcendent God is deprived of it.

God’s transcendence of the natural world is not, therefore, what makes Him worthy of reverence. Rather, transcendence marks Him as the God of epistemological philosophy. Though Christianity inherited the belief that God is the creator of the natural world from Judaism, His transcendence of the natural world is explained in Christian theology in a way that depends on Western philosophy. Ever since Augustine, at least, it has been explained in terms of Plato’s dualism of Becoming and Being (albeit by way of its transformation into a more idealist, neo-Platonist metaphysics by Plotinus). Plato first used the dichotomy between naturalistic and subjectivistic understanding (together with the radically different phenomenal appearances of the objects of each form of understanding) to explain what is good in the natural world as deriving from a supernatural source. And deriving from a form of metaphysical dualism that results from the epistemological approach to philosophy, it is not surprising that the belief in a transcendent God leads to serious theoretical problems. The problems are all solved by ontological theology.

The Problem of Proving God's Existence. The most immediate problem of traditional theology is proving God's existence. The dualism entailed by realism in epistemological philosophy usually leads, as we have seen, to doubts about realism, or anti-realism, and in the case of Christian theism, that means atheism. The transcendence of God makes it impossible to prove His existence from within space and time. But it is possible, as we have seen, to prove the existence of an immanent God, for this is a spatiomaterial world of the right kind.

The metaphysical dualisms of epistemological philosophy are inherently problematic. Plato could not explain adequately how two such different substances as Being and Becoming are related as parts of the same world. Christianity escapes being embarrassed by that problem only by insisting that the relationship is just part of the mystery about God. Though as persons (or rational beings), we are supposed to be created in the image of God, we are finite rational beings, and thus, we must simply accept the mystery and have faith in God. But the mysteriousness of God cannot, as such, make God worthy of worship. At best, the mystery merely leaves the possibility that God will turn out to be holy. And at worst, it is a mask that could just as well be worn by an evil or contemptible being and faith could be our undoing.

The Problem of God's Foreknowledge. Nor does the dualism of God and nature escape the theoretical problems inherent in a Platonic metaphysics. For example, God, being perfect, is supposed to be omniscient, as well as omnipotent and absolutely good. But since He exists outside of time as the creator of the natural world, He creates all the moments in the history of the natural world at once, including everything that finite rational beings ever do. Thus, God must already know what each individual will choose in each situation she faces. But that is hard to reconcile with the belief that individuals have a free will and that what becomes of us and the world is the result of our doing it. The future is not open. It is always already determined what we will do. Thus, God’s foreknowledge of what will happen seems to deny that rational subjects are free to choose in the way they think they are.

No such problem arises from the belief that God is immanent, even though God is still a perfect rational being, including omniscience, because knowing everything that it is possible to know as a rational being constituted space and matter does not include knowing what every rational being will ever do. It is possible to know what individuals have done in the past. And it is possible to know what will happen in the long run because of global regularities. But there are no necessary truths about what rational beings will choose in particular situations. That is among the contingent details that can be known only through experience of the world. (Nor is there any reason to believe that actual choices can be predicted by knowing how the bits of matter constituting a rational subject are moving and interacting.) In any case, since what exists are substances that endure through time, the future is open in the sense that it depends on what we choose to do (along with what else is happening at the time). Thus, the belief in an immanent God solves the traditional problem about God’s omniscience imply foreknowledge of our choices.

Nothing that Christians must give up, if they accept the foundation of ontological philosophy and accepts the necessary truths that follow from it, shows that the immanent God entailed by spatiomaterialism is any less worthy of worship than their traditional God. What changes is one's conception of the nature of existence, and that has implications about the nature of perfection that can be conceived in such a world. Thus, even though ontological philosophy must deny that God transcends the natural world, that does not mean that there is no perfect being, for as it turns out in a spatiomaterial world like ours, the world itself is as perfect a perfect being as can be conceived to be made of space and matter. And that perfect being is demonstrably worthy of worship, if the God of traditional Christian theology is. Indeed, ontological theology would have to include the doctrine of the trinity, quite apart from Christian theology, because the ultimate perfection of the world comes from how perfect rational subjects have three kinds of self interest: individual, spiritual and religious. Far from denying the doctrine of original sin, ontological philosophy clarifies what it is. With that clarification of original sin is, it not only confirms the Christian belief about the meaning of life being the struggle to overcome sin, but it points the way to overcoming it. Salvation is surely no less valuable for being achieved by reason rather than by faith. The denial of personal immortality may seem to be a sticking point for some, but the desirability of immortality is an illusion that comes from failing to recognize the basic nature of the life of individual reflective subjects, for when it is understood ontologically, its natural perfection precludes immortality. Indeed, it would be hell, and as it turns out, there is no hell, according to ontological theology.

If, therefore, the Christian God is worthy of worship, the perfect rational being that the world turns out to be, according to ontological philosophy, is no less worthy of worship. On the contrary, the insights into the nature of God make Him more worthy of worship. Not only is it possible to know about God without a leap of faith, but it is possible for reason to know what work it is that needs to be done in the name of God.

The Conclusion

With this explanation of how there is a perfect being in a spatiomaterial world like ours (see Religion), we have not only finished explaining how the world is whole, but have also paid off the last of the four mortgages that we took out in order to use spatiomaterialism as our foundation for proving necessary truths about the world. The final way that the world is whole is that God is immanent in the world, instead of transcending it. The world itself is a perfect being. Not only does the basic nature of the world give rise to progressive evolution, but the perfect rational being that inevitably comes into existence through evolution as ontological reason recognizes that there is something worthy of worship in a spatiomaterial world like ours is a perfect personal being. That not only explains the phenomenon of religion, but explains it in the most compelling way, namely, by showing that God exists necessarily in a spatiomaterial world like ours.

Let us first look back at the structure of the foregoing argument, confirming that its foundation is firm and that it is indeed a new way of doing philosophy, for that will put us in a position to see where we are landed here at the end.

Even though we had established that spatiomaterialism is the best ontological explanation of the world, if it is possible, it was necessary to take out three mortgages it order to use spatiomaterialism as the foundation for this philosophical argument, because there are certain phenomena that make it seem impossible. These phenomena were the existence of consciousness, the truth of Einsteinian relativity, the nature of goodness, and the widespread belief in the existence of something that is worthy of worship. Holiness has just been explained, for we have seen the sense in which God creates Himself in the rich soil of philosophical spiritual animals as ontological philosophy evolves. But before looking around to see where this argument had landed us, let us recall how the other three mortgages were paid off in the course of deriving this final necessary truth from spatiomaterialism.

Consciousness. The existence of consciousness was explained as one of the basic kinds of properties that exists in a world made of many material substances. Properties are aspects of substances that exist because the substances themselves exist, and in order to have properties by which they can have relations to one another, substances must be something in themselves. Since they must exist in some way or other in themselves, substances must have intrinsic properties and properties of that some kind can, in principle, explain consciousness.

Extrinsic properties are the properties that enable substances to have relations to one another. They include all the physical properties, though in in a world constituted by space and matter, as we have seen, there is a difference between two kinds of extrinsic properties. There are extrinsic properties of matter (and space) that enable bits of matter to coincide with parts of space (including motion), and there are extrinsic properties of bits of matter by which bits of matter that coincide with parts of space can be related to other bits of matter (that is, are able to interact with one another). The former account for location and motion, and the latter for interactions.

The ways that bits of matter are in themselves are their intrinsic properties, which afford an ontological explanation of consciousness. The so-called "hard problem" about consciousness is the fact that experience has an appearance or feels like something, and the intrinsic natures of bits of matter are of a kind that can, in principle, explain the simple sensory qualia, such as green and b-flat, that seem to be the elementary parts of the appearance that the natural world has for the subject in perception. (See .)

Furthermore, if the intrinsic properties of bits of matter can explain qualia, they can also explain the complex configurations of sensory qualia by which qualia appear to be located in (phenomenal) space (along with other phenomenal properties). Given how the mammalian brain is structured to serve as a faculty of imagination, the photons it generates have extrinsic natures (the spatiotemporal structure they have as a result of being generated by the thalamocortical projection) that register the activity of the brain as a behavior guidance system, and thus, their intrinsic natures would explain the complex phenomenal properties that things have as subjects experience them (and as rational subjects reflect on them). Assuming that phenomenal properties are intrinsic properties, rational beings in a spatiomaterial world like ours are inevitably conscious. (See Change: Unity of consciousness.)

Absolute space. The truth of Einsteinian physics was explained in the course of deriving from spatiomaterialism truths about change. Changes in properties and relations that happen over time are simply aspects of the world that are constituted by the basic substances, space and matter, because of their nature and how they exist together as they endure through time. Beyond the principles of local motion and local action, which are ontologically necessary, there are local regularities about change that do not follow from spatiomaterialism, but are compatible with it. These contingent laws are known from experience of what happens in the world, and since those laws include the basic laws of contemporary physics, another mortgage had to be taken out on spatiomaterialism. That is, Einstein’s two theories of relativity are generally thought to be incompatible with absolute space and absolute time, and since absolute space and time are entailed by spatiomaterialism as an ontology of substances enduring through time, we had to promise to show that spatiomaterialism can explain the truth of Einstein’s theories of relativity in order to take spatiomaterialism as our foundation. That explanation was given in the course of showing how spatiomaterialism can explain the truth of all the basic laws of physics (see Special theory of relativity and General theory of relativity under Change). We did that and then went on to show that spatiomaterialism can also explain the truth of quantum mechanics and cosmology (including a spatiomaterialist theory of the basic particles of physics and a spatiomaterialist theory about how the universe is eternal, which could explain the apparent truth of big bang cosmogony). Thus, the theories of physics describe quantitatively precise regularities about change that we know could be constituted by space and matter enduring through time.

Nor is it puzzling why this has been overlooked by physics. Physics assumes that the only way of knowing about the nature of the natural world is to infer to the best efficient-cause explanation of what is perceived, and since the mathematically simplest theories for predicting quantitatively precise changes refer to spacetime, instead of space as a substance in time, it has been led to believe that space cannot be absolute.

Goodness. The nature of goodness was explained in the course of deriving truths about evolution as a global regularity constituted by space and reproductive cycles. Goodness poses a problem for every contemporary kind of naturalism, because what is currently known by science (especially contemporary Darwinism) does not seem to afford any explanation of the difference between facts and values that does not make values subjective, that is, mere projections of the feelings, beliefs or special interests of human beings onto the world, suggesting that nothing corresponds to them in natural world. But with the proof that evolution in a spatiomaterial world like ours is change in the direction of natural perfection, it was possible to explain what is good as what contributes to the natural perfection of the whole of which it is part. (See Natural perfection: Goodness under Reproductive Causation under Change.)

All the kinds of things that are usually thought to be good turn out to be true, according to this evolutionary theory about the nature of goodness, including not only what is good for organisms of all kinds and the ecology, but also what is in the individual, spiritual and religious self interest of rational beings. (See What ought to be.)

However, not only does it explain what is good, the ontological explanation of the nature of goodness also explains why the good is good. It is good because it contributes to natural perfection. Natural perfection is the kind of perfection that is appropriate to a spatiomaterial world like ours, because evolution makes the most out of the material and structural global regularities, that is, out of the basic nature of matter and space. There is a general direction of change in the world because of the thermodynamic flow of matter from potential energy to evenly distributed heat, and what evolves are structural causes that use the free energy provided to make things happen in the world that would not otherwise happen. The optimal part-whole relation is one that does the most with the least, and since in this case, the part-whole relation is how structural causes are combined to control relevant conditions in the world, such part-whole relations are optimal when they control relevant conditions as much as possible with the fewest and simplest structural causes. That is, evolution produces as much order out of chaos as is possible. And the parts that contribute to such optimal part-whole relations are good because they contribute to natural perfection.

Since all four mortgages have been paid off, there is no good reason to doubt that spatiomaterialism is true. No other phenomena in the world seems even remotely incompatible with spatiomaterialism. We conclude, therefore, that what seems to be the best ontological explanation of the world is actually the true explanation of the nature of what exists. We and our world are constituted by space and matter as substances enduring through time.

The implications of spatiomaterialism about the world are, therefore, ontologically necessary relative to what is known by ordinary arguments and the experience of what happens in the world. That is the structure that the whole diagram represents the argument of ontological philosophy as having.

Though spatiomaterialism is itself established by an empirical argument, it is prior to empirical science and all the ordinary arguments in the culture of rational level spiritual animals, because it is the conclusion of an inference to the best ontological-cause explanation of the natural world, rather than an inference to the best efficient-cause explanation. And by and large, the ontologically necessary truths that follow from it are not recognized (though some are merely not recognized as being necessary for ontological reasons), because naturalists have failed to recognize that spatiomaterialism is the best ontological explanation of the natural world (as a result of their inference to Einsteinian physics as the best efficient-cause explanation of what happens at high velocity and in gravitational fields).

Since most of the ontologically necessary truths that follow from spatiomaterialism depend on space and matter having the detailed natures described by the basic laws of physics, most are conditionally necessary and hold only in spatiomaterial worlds like our own. They depend on the laws of physics being true. But since there is no reason to doubt that the laws of physics are true as far as they go, there is no reason to doubt these truths are ontologically necessary in our world. And these ontologically necessary truths are most surprising, for they include an ontological explanation of evolution as a global regularity which implies that evolution is progressive, that is, change in the direction of natural perfection, thereby explaining goodness as contributing to natural perfection. Moreover, evolution follows an inevitable course through a series of stages of evolution up to rational beings like us and beyond.

Ontologically necessary truths are the context of the contingent. That is, necessary truths constitute the possibilities and set the limits to what actually exists in the world. The contingent is “contained” by the necessary, and thus, there are two levels of contingency, according to ontological philosophy. What spatiomaterialism entails holds of every possible spatiomaterial world, and that is the context in which we explained the truth of the laws of physics. Second, the nature of what exists in a spatiomaterial world like our own gives rise to all the differences among material objects and alternative ways in which events can unfold. From all that is possible, only some possibilities come into existence. That is the actual. The world exists only at the present moment, and it is contingent, insofar as it depends on how the world was at some earlier time. But global regularities about change are among the necessary truths, and that means that in a wide range of circumstances, regardless what else happens, certain kinds of events will occur and certain kinds of objects will come to exist, including the entire course of evolution.

Ontological philosophy has, therefore, established itself as a new way of doing philosophy, which is unfazed by the problems that have plagued traditional epistemological philosophy.

It is a way of doing philosophy, because, like epistemological philosophy, it is a two step argument, which would unite all the arguments of rational-level culture into a single argument. First, it establishes a foundation, and then it uses that foundation to prove that certain propositions hold necessarily. But instead of using as its foundation a theory about the nature of reason that is formulated on the basis of what rational subjects know about knowing by reflecting on how they know and showing that certain proposition are known with certainty, it uses as its foundation a theory about the nature of the basic substances that constitute everything in and about the world and shows that certain aspects of the world are ontologically necessary.

Thus, instead of assuming that intuition is a valid way of knowing about the world, ontological philosophy assumes that substances are a valid way of explaining what exists in the world. And instead of epistemologically necessary truths about the world (including the various forms of "realism" that are supposed to be known with certainty), it defends ontologically necessary truths.

Its necessary truths eventually put ontological philosophy in a position to give its own explanation of the nature of reason, including the appearance that reason involves an intuition of some kind (that is, the phenomenal properties generated by a brain with rational imagination as the intrinsic natures of the photon it gives off), and thus, it explains all the same phenomena as epistemological philosophy. That affords an ontological critique of epistemological philosophy.

In the end, therefore, ontological and epistemological philosophy can both be seen as arguments about arguments. That is what makes them a higher level of forensic organization in the evolution of arguments in culture by rational selection. But since ontological philosophy succeeds in explaining everything in and about the world, it unites all the arguments of reflective stage culture and there is no room for the kinds of disputes that arose within epistemological philosophy. There may still be disputes, but they will be of a different kind.

Nor will the disputes that do persist cripple ontological philosophy in the way that epistemological philosophy has been crippled by its problems. Though epistemological philosophy is also an argument from the whole to the part, the "whole" from which epistemological philosophy argues is just a theory about the nature of reason, rather than an theory about the nature of what exists in the world. And since epistemological philosophy has different ways of explaining the nature of reason, it has, as we have seen, different ways of explaining the validity of ordinary, first level arguments (of rational spiritual animals). But there is only one way of explaining how the world itself is whole, if we establish our philosophical foundation by inferring to the best ontological explanation of the world, and thus, there is no room for alternative ways of doing ontological philosophy.

At this point, however, it is relevant to recall what we acknowledged at the beginning, that this argument is not just a new way of doing philosophy, but equally a new way of doing science. Indeed, it is the unification of science and philosophy. That is what I have been calling "ontological reason."

Science and philosophy look like mutually exclusive alternatives, because they have different methods. Science is committed to the empirical method, whereas philosophy aspires to find a higher or deeper foundation for knowing that will unite all the arguments of culture into a single argument and justify propositions that are necessary relative to them.

In the end, however, science and philosophy are identical. What unites them is empirical ontology. And empirical ontology is a legitimate heir of both science and philosophy, though it ultimately assimilates both of them, uniting them as aspects of a single way of knowing.

Science provides the empirical method, and philosophy supplies the notion of ontological explanation. Hence, "empirical ontology."

To be sure, empirical ontology requires philosophy to accept the empirical method as the way of determining which ontology is true. That means giving up epistemology as the foundation of its two-level argument, because its ontological beliefs will be determined by what is the best ontological-cause explanation of the natural world, rather than by what supposedly follows from its reflection-based theory about the nature of reason. But philosophy will keep its philosophical method, because it will use that ontology as a foundation for demonstrating necessary truths. The difference is that those truths are ontologically necessary, rather than epistemologically necessary, or certain, as traditional epistemological philosophy assumed.

Empirical ontology requires science to change as well, for science must accept the validity of ontological-cause explanations, as well as efficient-cause explanations. Since ontological-cause explanations are prior to efficient-cause explanations, that is to recognize empirical ontology as a more basic branch of science than physics. And that is what requires science to give up Einsteinian spacetime in favor of the belief in space as a substance enduring through time (with an inherent motion). But ontological science is no less empirical, and it will keep all the efficient-cause explanations of natural science. The conclusions of empirical science describe aspects of the world (namely, regularities) that must be explained ontologically. But such an ontological reduction of the laws of science to spatiomaterialism is quite fruitful. Inferring to the best spatiomaterialist explanation of the basic laws of physics leads to deeper theories in physics, solving basic problems confronted by contemporary physics, and the reduction of laws in less general branches of science to spatiomaterialism leads, for example, to the discovery of new global regularities, such as the inevitable course of evolution.

Indeed, the ontological explanation of the conclusions of empirical science is essential to ontological philosophy, because that is what gives ontological philosophy a theory about the nature of reason by which to unite all the arguments of rational level culture as parts of a single argument about the world. Without science, ontological philosophy could not succeed in doing what epistemological philosophy tried and failed to do. Though it could still demonstrate more elementary necessary truths about the world, physics is required to show the inevitability of evolution, and without contemporary neurophysiology, it would not be possible to trace the stages of evolution to an explanation of the nature of reason. Since the ontological critique of epistemological philosophy depends on that ontological reduction of reason, ontologists without modern science would be no better off than the Pre-Socratic philosophers. Ontological reason would still lie in the distant future.

In other words, empirical ontology makes both science and philosophy ontological, and the union of ontological science and ontological philosophy is "ontological reason."

It may seem that after the advent of ontological reason there is still a difference between science and philosophy. Each may seem to use the spatiomaterialist ontology in a different way. Science will use spatiomaterialism to explain why its laws and efficient-cause explanations are true, that is, to reduce them to ontology. On the other hand, philosophy will use spatiomaterialism to show why certain propositions about the world are necessary.

These projects are not, however, as different as they seem. The argument by which ontological philosophy demonstrates necessary truths is formally the same argument by which the conclusions of science are reduced ontologically. And it is the ontological necessity of those implications of spatiomaterialism that supplies the long-sought explanation of causal necessity. The necessary connection between efficient causes and their effects (which eluded Hume) is provided by taking into account the substances constituting the relevant events, because substances endure though time with the same nature.

Thus, science and philosophy are parts of a more complete knowledge. Philosophy provides science with the necessity that it needs, and science provides philosophy with the method that it needs to establish its foundation as well as the detailed conclusions about efficient causes that are needed to explain the nature of reason.

At the beginning, I said that ontological philosophy is an explanation of the wholeness of the world, but that I could not explain fully what I meant by “the wholeness of the world” until the end. We are now in a position to see what it means. To explain the wholeness of the world is to explain how everything fits together as a whole. And ontological philosophy reveals, as we have seen, that everything fits together as a Perfect Being. The wholeness of the world is ultimately the perfection of the world. It includes all the others forms of wholeness, for they all make essential contributions to the perfection of the world.

An ontological explanation of the world can claim to be whole because it offers a complete explanation of everything in the world, not only its existence, but every aspect of its existence, including all the properties, relations and regularities about change. And spatiomaterialism had a special claim to explaining the wholeness of the world, because it differs from received ontologies by recognizing the existence of a substance that makes the world whole. Space not only provides a location for everything in the world, but also, by enduring through time with all the matter, imposes local and global regularities on the change that takes place in the world. Moreover, the large scale structure of the universe inevitably gives rise to situations in which evolutionary change takes place over long periods of time. Evolution is change in the direction of a natural perfection that includes rational beings, like us, who come to recognize the wholeness of the world. Hence, it inevitably leads to beings who act for the good of the world as a whole, making the world more perfect, more whole.

There is, therefore, an Absolute Truth about the world. Not only does it hold for everyone in the world, but it is also the complete truth about the world. And since it shows that the world itself, because of its nature, is a Perfect Being, it answers all the most profound questions that rational beings can expect to be answered. The Absolute Truth is, in short, the explanation of the wholeness of the world, which reveals that the world itself is perfect.

The world is a way of existing that makes the most of existence.

Hugh Renbircs
Philosopher

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iIt might be argued that ontological philosophy relies on only one assumption, naturalism, because the other two assumptions might be shown to be consequences of it. We are defining naturalism as the assumption that the world is just what exists in space and time. Since that is an ontological definition, we might already be committed to explaining the natural world by substances and the relations among them, for we will need self-subsistent entities of some kind to explain its existence. Thus, naturalists already accept, in effect, the validity of ontological explanation. And since the world of objects in space and time we mean is the one that is disclosed to us by perception, we might already be committed to using what is perceived as evidence in choosing what to believe about it. Thus, naturalists already accept the empirical method, assuming that the standard of the best explanation is implicitly in the nature of the explanation being given. Hence, naturalism might be said to be the sole assumption for the foundation of ontological philosophy. But the argument is not put that way here, because to start by trying to defend a way of knowing about the world (or a way of explaining it) as implicit in naturalism would obscure the difference between ontological and epistemological philosophy. In the present context, it is better simply to distinguish the three assumptions and make them independently, since they are all equally plausible.

iiIt may seem that there is a way to for the perdurance theory to explain the present without dismissing the phenomenon of the present as an illusion, and it is relevant to mention it here, because it was first suggested by Hermann Weyl ([1921], p. 217) in defense of the perdurance theory entailed by taking spacetime to be a substance. Einsteinian relativity had led, as we shall see in the next section, to the belief that what exists is a spacetime world in which the momentary substances making up permanent substances are spacetime events, and Weyl said, "The great advance in our knowledge . . . consists in recognizing that the scene of action of reality is not a three-dimensional Euclidean space but rather a four-dimensional world in which space and time are linked together indissolubly. However deep the chasm may be that separates the intuitive nature of space from that of time in our experience, nothing of this qualitative difference enters into the objective world which physics endeavors to crystallize out of direct experience. It is a four-dimensional continuum, which is neither “time” nor “space”. Only the consciousness that passes on in one portion of this world experiences the detached piece which comes to meet and passes behind it, as history that is, as the process that is going forward in time and takes place in space."

Weyl is assuming that empirical falsification of substantivalism about spacetime can be avoided by holding that the present is just how spacetime and the spacetime events it contains appear to “consciousness”. Though such a response may be acceptable in epistemological philosophy, it leads to an ontology that is decidedly inferior to the endurance theory, because it is more complex and problematic. To assume that consciousness “passes on” is to assume that it undergoes real change, and thus, to follow Weyl is to postulate, in addition to spacetime and the spacetime events that it contains, some substance that does endure through time, always existing at each moment as it is present, namely, consciousness. If consciousness is postulated as a subjective substance, spacetime substantivalism will not only be more complex (now postulating three basic kinds of substances), but it will also face a serious ontological problem, for it must then be explained how enduring substances can be related to non-temporal substances. Indeed, it would be an ontology with two different concepts of time, one that is part of the structure of spacetime and another that characterizes the existence of consciousness (as a substance enduring through time). That twofold use of time complicates the perdurance theory in a way that makes it not only more complex simpler, but also far more problematic.

Weyl's approach is still a common response, however. For example, see Penrose [1989], pp. 442ff. And though McCall [1994] is only trying to rescue the openness of the future, his ontology (or “model of the universe’) is also made more complex and problematic by requiring both these concepts of time.

iiiTo hold that only the present exists is to take sides with the so-called “tensed theory of time” in a current dispute in the philosophy of language (Oaklander and Smith, [1994]), but that does not mean that the perdurance theory can be defended by endorsing the “tenseless theory of time”. The endurance theory would hold that the tensed theory of time is correct in holding that statements about past, present and future say something about the world that is not implied by tenseless descriptions of before- and after-relations that hold among events (or by analyzing the truth conditions of such statements as indexical references to the moment of their utterance) The tenseless theory must deny that only the present exists, for otherwise it would have to admit that statements about past, present, and future are something more than descriptions of an event’s before or after relations to the moment of their utterance. Such statements uttered at present would also be (true) descriptions of how the event is related to what exists. And those uttered at other moments would have no truth value, for they wouldn’t exist at all.

There may be a standoff between these two views in the philosophy of language. But that is not relevant here, because our reason for preferring the endurance theory is not based on analyzing truth conditions of statements about the past, present and future. It is an argument in empirical ontology. I am arguing that the best ontological explanation of the world disclosed by perception, including the observation of real change, is to postulate only enduring substances.

The tensed theory has not been defended in this way in the recent debate. Appealing to what we observe is not the same as appealing to phenomenology, as in Part III of Oaklander and Smith [1994]. The former argument is not refuted by pointing out that the observation would have the same causal connections on the timeless view, for it is about the content of the observation, not its causal role. And though this view implies that there are properties of “presentness”, “pastness” and “futureness”, their meanings are explained in terms of existence: the present is what exists, while the past and future do not, albeit for opposite reasons. Thus, contrary to Williams [1994], there is a basic disanalogy between “presentness” and “hereness”, for what is opposed to the former (past and future) does not exist, whereas what is opposed to the latter (what is over there) does exist.

Nor is a theory that explains how the present is different from the past and future by its existence plagued by the paradoxes that are supposed to undo the tensed theory of time. For example, it avoids McTaggart’s paradox about time, for it is not committed to there being events that have first the property of being future, then the property of being present, and finally the property of being past, for nothing exists but what exists at present. Nor are there sentences about past, present and future changing truth values, for the only sentences that exist (and are capable of being either true or false) are in the present.

ivThus, the acceptance of Einstein's theories was not merely the result of empiricist skepticism about unobservable, theoretical entities. The prevailing empiricism in the philosophy of science may have been what inspired Einstein to formulate the special theory of relativity, as is widely believed, but what led to its acceptance was the scientific method. If absolute space and time had been just unobservable entities mentioned by scientific theories, they would have survived the philosophical doubts engendered by logical positivism. After all, logical positivism did not convince physicists to give up such unobservable theoretical entities, including electrons, neutrinos, quarks, force fields and the like. Doubt about the reality of absolute space and time came from their not being mentioned by the best scientific theory of the relevant phenomena. That is, there was no way to test, even indirectly, whether or not they exist, because unlike theoretical entities, they made no difference at all to what happens in the world. It was the scientific method that led to their denial. In other words, absolute space and absolute time were more like metaphysical entities of the kind that the logical positivists had originally and more justifiably intended to exclude from empirical science, such as immaterial minds, immortal souls, and angels.

vThis kind of emergentism is implied by Searle in The Rediscovery of Mind, though his confusion about ontological issues would probably lead him to deny it. For a less confused discussion of the difference between emergentism and epiphenomenalism, see Caston

viSome such view was also suggested by Russell (1927) as "neutral monism" and more recently by Lockwood (1989, pp. 156-171). It was also suggested by Feigl (1958), Maxwell (1978), and Robinson (1982).

viiChalmers considers another possibility, which he calls "strong metaphysical necessity." It holds that there is a difference between logical and metaphysical possibility, so that some of what seems to be logically possible is not metaphysically possible. If the range of metaphysically possible worlds is smaller than the range of logically possible worlds, it may turn out that even though there are logically possible worlds in which zombies exist, there is no metaphysically possible world in which they exist.

The obstacle to this approach is making the premise about the range of metaphysically possible worlds more than an ad hoc, dogmatic assertion. And Chalmers cannot see how that is possible. Thus, in a subsequent response to his critics, Chalmers (1997), uses Loar (1997) as an example of this strategy, and his refutation of Loar belies the error both are making in taking properties to be basic. He interprets Loar as taking the identity of physical and phenomenal properties to be a metaphysical truth and then trying to explain why this property seems to be two different properties by a difference in the concepts we use to refer to it. The concept of physical properties involves the use of theories and observational evidence for their application, whereas we have a "recognitional concept" of phenomenal properties (that is, our concept depends on how they appear to us in reflection). But in order to make good on this view, Loar must explain how such different concepts could be concepts of the same properties, and Chalmers’ objection is that Loar does not provide it. Ever since Kripke, the usual way of explaining how concepts can refer to the same property and yet be cognitively distinct is to show that one of the concepts picks out its property by way of a contingent fact, such as its causal role. But that is not what Loar does. On the contrary, Loar (p. 608) holds that the recognitional concept of phenomenal properties "expresses" the essential nature of phenomenal properties and that the concept of physical properties "expresses" the essential nature of physical properties. This undercuts the credibility of his claim that that these concepts refer to the same property, for it is hard to see how one and the same property could have two different essences. And to insist that it does because it is metaphysically necessary is to beg the question. It is to assert dogmatically that an identity is metaphysically necessary.

viiiChalmers (1996) takes the grounds of physical properties to be intrinsic properties, rather than substances that also have intrinsic properties. The omission of substance is also implicit in his definition of "materialism" as "the doctrine that the physical facts about the world exhaust all the facts, in that every positive fact is entailed by the physical facts" (p. 124). The same reason also keeps Russell and Lockwood from even suspecting that the connection is necessary. Russell (1927) is explicitly skeptical about the existence of substances, preferring to reduce substances to sets of physical events located in spacetime. Thus, he sees the intrinsic properties to which physical events are connected as mental events with the same locations in spacetime, a view he calls "neutral monism." Lockwood (1989) is a "causal realist" who takes the physical properties to refer to "whatever it is that occupies the relevant positions within a certain causal structure" (160), and so the door is open for him to hold that they are occupied by intrinsic properties.

The connection between intrinsic and extrinsic properties can be seen as an example of what Chalmers (1996, 137) calls "strong metaphysical necessity" as opposed to the "weak metaphysical necessity introduced by the Kripkean framework," for it holds that there are "fewer metaphysically possible worlds than logically possible worlds." But it is not the dogmatic position that Chalmers assumes it must be, for we are merely restricting possible physical worlds to those in which the elementary bits of mass and energy described by physics are substances. This is a far cry from insisting dogmatically that phenomenal properties are metaphysically identical to physical properties, as Chalmers (1997) accuses Loar (1997) of doing. Loar’s way is mere "ontological stipulation." But instead of holding that properties are identical, we are reducing properties to the substances that constitute the existence of the world and explaining the relationship between physical and phenomenal properties as different aspects that the essential natures of certain forms of material substances must have.

ixIndeed, if phenomenal properties are the intrinsic essential natures of the photons generated by the active brain, as I will argue later, they are epiphenomenal is a twofold sense, for in addition to being intrinsic essential properties of matter, the bits of matter they are intrinsic properties of are not themselves the efficient causes of what happens in the brain. That depends on how the neurons affect one another locally, not on the photons they generate jointly. For a discussion of what this implies about the nature of out knowledge of phenomenal properties, see the discussion in Change: Unity of Consciousness.

xFor an accessible discussion of the problem of certainty in the philosophy of mathematics, see Kline (1980). A somewhat more technical, but still readable discussion of issues about infinity is Lavine (1994).

xiCovert manipulation also makes it possible to combine images of effects of motion from locomotion imagination into a single geometrical structure in manipulative imagination to think about all the relations of the objects in some territory at once, like a map.

xiiIn a much discussed paper, Benacerraf (1973) argues against Platonism on the ground that it is not compatible with a causal theory of mathematical knowledge. Bigelow (1988) nevertheless takes universals to be the objects of mathematics, and he avoids this problem with abstract entities by following Armstrong (1983) and assuming, in effect, that universals are just spatial relations of bits of matter, which are always instantiated (that is, as so-called "tropes").

xiiiThis is similar to the "skeptical fictionalist" view of mathematical truth defended by naturalists like Field (1980) and Papineau (1993, pp. 193-197). They think that they must deny the existence of mathematical objects because such objects are abstract. But that is because they do not recognize the ontological role that space plays in making arithmetic true. They are implicitly materialists (taking space to be just spatial relations) who are nominalists about the concepts used in science, and though they recognize that mathematics can facilitate complex inferences about the natural world, they believe that all those inferences could, in principle, be made without referring to numbers or geometrical figures as abstract entities. Thus, they take such numbers and geometrical figures to be useful fictions and are skeptical about their existence. But that makes it just as puzzling why mathematics holds of the natural world as Platonism does. However, if space as a substance containing all the bits of matter is the ontological cause of geometrical figures and the groupings of material objects called numbers, there is an alternative, non-fictionalist defense of geometry and arithmetic truth. Though there is every reason to be skeptical about the existence of mathematical objects that are abstract entities, that is no reason to believe that numbers are just useful fictions. They could describe something concrete -- a very general, ontological effect of the structure of space on the bits of matter it contains.

xivKitcher's approach is endorsed by other philosophers of mathematics, such as J. Bigelow (1988, p. 3). Bigelow holds that mathematics is about universals, but he follows Armstrong's (1983) "a posteriori realism" in taking universals to be physical, and thus, in the terms used here, he is a materialist. Indeed, the subtitle of his book is "A Physicalist's Philosophy of Mathematics".

xvThe traditional theory about mathematical truth that comes closest to Kitcher's is abstractionism, the view originally defended by Aristotle that mathematical objects are abstractions from perceived objects. See Körner (1960, pp. 18ff). Kitcher has a more sophisticated theory about how mathematics is derived from perception than Aristotle. According to his "evolutionary theory of mathematical knowledge" (p. 92), the abstractions come from idealizing the operations of arithmetic, though Kitcher insists that this is compatible with saying that "arithmetic describes the structure of reality" (p. 109).

xviThe assumption that the use of language makes spatio-temporal imagination a cognitive capacity of reflective subjects enables spatiomaterialists to answer objections that Kitcher (1983, pp. 50ff) raises to intuitionism (or "constructivism'). Contrary to Kitcher, it is possible to distinguish essential properties from those that are accidental, because imagination is not just "pictures in the mind", but images that reflective subjects construct and manipulate within its structure. When a geometrical figure, such as a triangle, is defined, it is constructed in imagination, and thus, assuming that language-using subjects can reflect on what they are doing, they can see the effects of varying triangles in all possible ways on their inferences about them. Second, although Kitcher is right to insist that infinite sequences of operations, such the division of a line, cannot be carried out in practice, subjects who can reflect on what they do in imagination and its effects can come to see that what will happen each time is limited in a certain way and, thus, infer what would, and would not, happen if the operations were taken to infinity. Finally, the problems about exactness that may arise with Kitcher's "mental pictures" do not arise with spatio-temporal imagination. For example, imagined straight lines cannot be crooked, for they are constructed according to the understanding of the structure of space that is built into the structure of spatio-temporal imagination, that is, as the path of the shortest distance between two points. In short, since ontological philosophers postulate space as a substance containing all the matter in the world, they need only recognize the basic role that a spatio-temporal imagination would play in the reflective subject's knowledge of the world to explain how reflective subjects have a priori knowledge of mathematical truth, because its structure corresponds to the structure of space. Indeed, without the capacity to see what is given in perception against the background of what imagination tells us is possible in three dimensional space, it is hard to see how we could perceive a line as straight, a set of three lines as a triangle, or anything as a mathematical object.

xviiThis is because the velocity of light relative to the object in motion is different in opposite directions, and going one way the whole distance at the lower (relative) velocity takes more extra time than it can make up coming back over the same distance at the higher (relative) velocity. Though the path back and forth is spatially symmetric, the effect of the velocity of light relative to the frame on the time of travel accumulates per unit time, and so the signal loses more time than it gains.

xviiiThe equation was L=Lo, where Lo was the length at absolute rest. The shrinkage had been proposed independently by George F. Fitzgerald in 1889 and hence became known as the “Lorentz-Fitzgerald contraction”. Relevant portions of Lorentz’s 1985 monograph and 1904 theory are reprinted in Lorentz, et al, (1923, pp. 3-84).

xixSee Stanley Goldberg (1984, p. 98) and Roberto Torretti (1983, pp. 45-6). Hereafter, these works are referred to as “Goldberg” or “Torretti”, with page numbers. “Holton” refers to Holton (1973). “Zahar” refers to Zahar (1989).

xxThe discovery of the Lorentz distortions was complicated by the fact that there are other effects of absolute motion on material objects, besides those that are directly related to the Michelson-Morley experiment. These are the “first-order” effects of motion in space (which vary as v/c, rather than as v2/c2, or “second order” effects), such as the way telescopes must be inclined slightly in the direction of motion in order to intercept light from overhead stars (much as umbrellas must be inclined slightly forward in walking through rain to keep raindrops from hitting one’s body). First order effects (including the effects on the index of refraction) had previously been explained by the “ether drag” hypothesis (that the motion of material objects drags the ether along with them), but Lorentz abandoned it . Lorentz’s explanation of length contraction assumed that the ether is totally unaffected by the motion of material objects through it, and he had no explanation of such first order effects except to state transformation equations by which one could obtain the coordinates used on the moving object from those used at absolute rest. Goldberg, pp. 88-92; Torretti, pp. 41-45

xxiZahar (1989), p. 99; Holton (1973, pp. 175-178).

xxiiProkhovnik (1985, Appendix 2) argues that in the original formulation of his argument, Einstein was actually assuming the existence of a stationary coordinate frame.

xxiiiH. Minkowski, “Space and Time”, reprinted in Lorentz, et al, The Principle of Relativity, pp. 75-91.

xxivSee, for example, M. Friedman (1983), J. Earman (1989), and J. R. Lucas and P. E. Hodgson (1990).

xxvProkhovnik (1985, Chs. 5-6) develops a similar argument in a mathematically general way, but the more intuitive approach used here brings out the ontological significance.

xxviThis distortion in longitudinal forces is not widely recognized. It is suggested in a few obscure discussions of the difference between “transverse mass” and “longitudinal mass” that follows from Einstein’s special theory. See Okun (1989). This complication in Einstein’s theory is not usually acknowledged in textbooks in this field (and I thank Howard Reese for bringing it to my attention). But since it makes no sense to suppose that mass is different in different directions, the only possible explanation of the principle of relativity (as opposed to mathematical deduction) is a relativistic decrease in longitudinal forces. Prokhovnik (1985) recognizes it, and he explains it mathematically as a retarded potential. (It is as if the force involved a two-way trip at the velocity of light in order to act).

xxviiThe slope of the moving space-line is found in the Newtonian diagram of space and time by calculating the difference between the absolute time of reflection, T₁, and the time halfway during the round trip, (T1 + T₂)/2, calculating the absolute distance between those events, and dividing the latter into the former.

xxviiiIn Minkowski’s derivation, the slope is the value of the first derivative of his equation for the hyperbola when t = x/v (i.e., when ), or v/c2. And the length of the unit of distance on the moving space-line is the distance required for light to have velocity c, that is, the distance light actually travels in a unit of time according to slowed-down clocks, which in terms of the length of the contracted rod, L', is also , or an effective expansion of the measuring rod at the square of the usual rate.

xxixThe Lorentz transformation equations that Einstein derived also imply that the others’ space-line at the point of coincidence of origins is represented by the line, t = vx/c2. Solve the moving observer's Lorentz transformation equations for both time and space on the assumption that t' = 0 (the moving space-line through the absolute origin) and combine.

xxxMathematically, where L is the absolute measuring rod, L'=L is the actually contracted moving measuring rod and L"= is the virtually expanded moving measuring rod, we know that L=L", and since moving observers mistakenly assume that L'=L", that is the appearance that the absolute measuring rod is contracted relative to the moving measuring rod.

xxxiMeasuring rods can also be measured with clocks, by timing how long it takes for the others’ measuring rod to pass by traveling at v. The absolute observers’ measurement is veridical, but the appearance to moving observers that absolute measuring rods are contracted results from using slowed down clocks. Mis-synchronization is also implicated in this appearance, for it is what gives moving observers the correct value for relative velocity, despite having slowed-down clocks and contracted measuring rods.

xxxiiMeasuring rods can also be used to time the others’ clock, by moving along with the other clock and comparing it with what clocks should read after traveling at the relative velocity, v, for a certain distance on our frame. Again, the absolute observers’ measurement is veridical, but the absolute clock seems slowed down to moving observers because their measuring rods are contracted. And mis-synchronizing clocks again plays a role in obtaining the correct value for relative velocity.

xxxiiiThis calculation of the effect of the mis-synchronization of moving clocks on the moving observers measurements of the speed of absolute clocks is also an interpretation of what is actually going on when one derives a prediction from the Lorentz transformation equations of what moving observers will find about absolute clocks. Assuming that the primed variables, t' and x', are those used by the moving observers, then the Lorentz transformation equation by which moving observers determine temporal coordinates in the absolute frame for time is . But since the observers’ motion is x' = VT, this equation becomes . The denominator represents the slowing down of moving clocks at the usual rate; the numerator represents the result of moving backwards past a series of mis-synchronized clocks, an effective speeding up of clocks at the square of the usual rate; and so the partial cancellation of the numerator by the denominator represents how they give rise to the opposite appearance, an apparent slowing down of the absolute clocks at the usual rate. This shows, at least, that there are factors of the right size working in the right way to produce the appearance.

In this case, the deduction for moving observers happens to correspond to the cause of the apparent distortion in the absolute frame, but the deduction does not always corresponds to the cause of the observation. It can’t because the deduction predicting time dilation is the same on both sides of any pair of frames. But there is a more complete symmetry among distortions involving opposite distortions on each side, and one of the two kinds of deductions predicting them always involves a mis-synchronization factor and the other does not, suggesting there are always two ways that measurements of distortions can be caused, namely, by real distortions and by the appearance caused by mis-synchronization.

xxxivThe relative velocity of a third moving frame relative to the first frame is given by Einstein’s formula for the addition of velocities, , where v is the velocity of the second frame relative to the first and w is the velocity of the third frame relative to the second. This formula is derived by using the Lorentz equations to transform the second frame’s description of the motion of the third frame into a first frame’s description. But if the second frame is at absolute rest, this formula yields the apparent relative velocity of two frames as a function of their absolute velocities: (since -v is the absolute velocity of the first frame when v is the velocity of the second frame relative to the first). This formula for the “subtraction of velocities” describes how observers on two frames moving through a third must appear to one another. There is no reason for Newtonians not to use the Lorentz transformation equations as an aid to calculation, since there is no dispute about the predictions, only about the causes. The apparent relative velocity is not, in general, the real relative velocity, u - w, because the latter can approach twice the velocity of light.

xxxvThe equation derived from the special theory of relativity describing the quantitative equivalence between energy and mass, E = mc2, is the foundation for the principle of the conservation of mass and energy which was used as the working hypothesis in the ontological explanation of classical physics.

xxxviNewton later suggested various mechanisms to account for gravitation. See Burtt (1980, pp. 264ff).

xxxviiThis equivalence can also be put mathematically, as Hoefer (1996) does: “By taking one model <M, g, T> and applying a diffeomorphism h (essentially, a permutation of the points in M satisfying certain restrictions), one can generate a ‘new’ model of the theory <M, g, T> which is qualitatively identical, but which has the material contents and the metric field distributed differently over the point manifold of M” (7-8).

xxxviiiThis is the orthodox approach, represented by Michael Friedman (1983), and John Earman (1989). But Earman and John Norton use the “hole argument” to raise doubts about the four-dimensional manifold of points being a substance are raised by the “hole argument”. See Earman and Norton (1987). But spacetime substantivalism has its defenders, such as Hoefer (1996). Though the spatiomaterialist theory does not need to answer the hole argument to defend its substantivalism about space, it may be relevant to mention that it sees the “hole argument” as an artifact of the mathematical formulation of GTR. Instead of seeing the models as different (locally) inertial frames used to assign coordinates throughout the universe with a certain standard of simultaneity, the hole argument interprets their observational equivalence as a mere mathematical operation (a diffeomorphism; see previous footnote), and that makes it possible to hold that there can be “holes”, or regions where, in effect, different standards of simultaneity hold. The spatiomaterialist ontological explanation of the observational equivalence of different models of GTR will be given at the end of this explanation of the general theory itself.

xxxixThe inherent motion in space is rather well represented by light cones in the familiar diagrams. Each light cone represents the range of all possible Lorentz equivalent inertial frames at its location, and the increased tipping of light cones in the direction of the center of gravity at locations nearer and nearer to that center represents the increasing velocity of the inherent motion itself. The “event horizon” around a black hole is where they tip so far that even the far side of the light cone is inclined toward the black hole.

xlCompare this with the spacetime explanation of Will (1986, pp. 69-74). Will traces the light ray’s path through spacetime by considering the series of free falling frames through which it would pass. He recognizes that the Newtonian-like half of the bending comes from a change in the angle of the light passing through each frame due to the inward acceleration as it passed through the previous frame. But in order to account for the other half of the bending, he argues that there is a “curvature of space” near gravitating bodies in which the number of measuring rods needed to measure a line passing by the sun would be greater than expected by triangulating the distance from outside the gravitational field. Though Will does not explain why measuring rods would be shrunken, spatiomaterialism would agree that free falling rods momentarily at rest relative to absolute space would be contracted, because they would be suffering a Lorentz length contraction due to their constant velocity relative to the ether (see page Error: Reference source not found). But that length contraction is merely a symptom of their velocity relative to the ether, and so the spatiomaterialist theory explains the other half of the bending more directly. There is no need to suppose that space itself is curved, only that the velocity of light in space is altered.

xliThis is a much simpler explanation than spacetime curvature affords. Compare with Will (1986, pp. 112-119).

xliiAcceleration in rectilinear motion causes an apparent time dilation whose rate continues to change as the velocity difference between the clocks continues to increase. A constant rate of apparent time dilation caused by the Doppler effect can occur outside gravitation only when the two clocks are located at the center and rim, respectively, of a rotating disk and the acceleration of the rim clock space always results in the two clocks having the same relative velocity in the direction of the signals between them.

xliiiThough the two kinds of time dilation both involve the acceleration of the inherent motion due that constitutes the force of gravity, they combine mathematically the same way as the Doppler effect and Lorentz time dilation due to motion outside gravitation, or the so-called “relativistic Doppler effect”.

xlivSee, for example, Friedman (1983) and John Earman (1989).

xlvFriedman (1983) argues that the four-dimensional continuously differentiable manifold, M, itself is all that should be taken as “absolute” in the sense of being a “geometrical structure that is fixed independently of the events occurring within space-time” (65). That is the only structure that spacetime has to have in order for the equations of GTR to predict the gravitational trajectories of bits of matter precisely (and provide the curved spacetime in which other laws of physics hold). Focusing on the mathematics of GTR and the scientific inference to the best efficient cause explanation, he does not consider what structure spacetime must have to be adequate ontologically and explain “real change”. That requires a further structure about spacetime to be absolute, an “ontological structure”, namely, the one in which spacetime consists of a three-dimensional substance (containing bits of matter) and exists only at the present moment.

xlviSee Cushing and McMullin (1989) for discussions of this issue.

xlviiAbner Shimony (1989, p. 31) points out that many pairs tested for correlation in Bell’s experiment are not detected and so a (local) hidden variable could “not only determine passage or non-passage or a particle through an analyzer but also detection or non-detection.” This possibility is also recognized by Bohm (1993, pp. 144-5).

xlviiiFermi postulated the neutrino as massless, and the only reasons for thinking it has a mass at all is that makes it possible to fit them into the current gauge theories of the basic forces more easily and if they have a mass, it may mean that there is enough mass in the universe for gravitation to cause a contraction, or at least, bring the expansion to an end. Neither of these reasons carry any weight on our approach, and thus, we assume that neutrinos are massless and travel at the velocity of light.

xlixTalk about free energy as the amount of information contained in systems is not helpful, if not misleading. Information is sometimes equated with free energy, as does D. Hawkins (1964), and others equate it with entropy, as do D. R. Brooks and E. O. Wiley (1988).

lAlthough we are treating gravitation as a force of attraction which supplies free energy, our ontological explanation of Einstein’s general theory of relativity has an implication that might be mentioned. Objects that have accelerated under the force of gravity are said to acquire kinetic energy, but since they are actually being accelerated with the acceleration of the ether, the potential energy does not become kinetic matter (and photons) until they crash into the center of gravity and join the thermodynamic flow of matter toward evenly distributed heat.

liThis other aspect of the tendency of potential energy to become kinetic energy is what Prigogine (1980) and Kauffman (1993, 1995) and their followers are think of as the mysterious phenomenon of “self-forming” or “self-organizing” objects. See the discussion of the Second law of thermodynamics in Epistemological philosophy of causation.

liiWhen they cool faster, crystals that form in different regions may fit together irregularly as amorphous crystals or even form a glass in which they are locked in bonds that are not as tight and strong as they would be in a crystal.

liiiThere are signs that some philosophers of evolution may have an open mind about alternatives to accidentalism that recognize a necessity about the functional traits that evolve. For example, see Dennett (1995).

livThis occurs in two different ways, marking the most basic difference between kinds of complex animals. In one case, the blastopore becomes the mouth and the second opening becomes the anus. In the other, the blastopore becomes the anus and the second opening becomes the mouth. The former animals are called proterostomes, whereas the latter are called deuterostomes. This is a significant difference that will occupy us later, for only in deuterostomes do stages of zoological evolution lead all the way to reason.

lvThe embryonic mouth then disappears and reappears later. See Earl D. Hanson, ”The Origin and Early Evolution of Animals• (London, Wesleyan University Press, 1977), pp. 511-513. Also R. J. Skaer, "Planarians," in G. Reverberi, (ed.), ”Experimental Embryology of Marine and Fresh-Water Invertebrates•, (Amsterdam, North-Holland Publishing Company, 1971), pp. 104-125

lviIn most higher animals, one kind of chromosome has two fundamentally different forms, called X and Y. Females have two X chromosomes, whereas males have both an X and a Y chromosome. However, only one of the X chromosomes is opened up in the female; the other X chromosome is wrapped up and set aside as a unit called the "Barr body." Both X and Y chromosomes are opened up in the male, and there is no Barr body.

lviiThe division of the egg cell, or cleavage, is highly indeterminate in the most primitive, ectolecithal flatworm egg, but it occurs in a regular way in flatworms with planuloid development and in all higher animals. It is likely that determinate cleavage ensures that cells with certain parts of the egg cortex or cytoplasm end up with the right location on the blastula in order for their behavior toward one another to construct the animal. The planuloid flatworms have either a duet-type spiral cleavage or the quartet-type spiral cleavage found in proterostomes. But deuterostomes have a radial cleavage, presumably because their kind of gastrulation and way of forming a mesodermal coelom is so different.

lviiiThe passing down of a portion of the egg cortex or cytoplasm to the right place in the blastula can be seen in the cleavage of certain mollusks; it is a "polar lobe" that is formed before each division that ensures that it is bestowed on the right daughter cell and thereby winds up in the right place on the blastula. In insects, the process of development is greatly modified. Instead of a regular process of cleavage, the blastula is formed directly from the egg cortex by the migration of copies of the egg nucleus to locations on its plasma membrane, where each nucleus separates itself by setting up a plasma membrane. But the effect is the same, since the mesodermal coelom still derives (by the splitting of a solid mass of cells) from a pair of cells that inherit a certain part of the egg cortex.

lixIn the sea star and other echinoderms, the mesodermal coeloms are spheres that pinch off from the endoderm in the blastocoel before the mouth is formed. But in chordates, it is a more refined process which also includes a similar out©pouching into the blastocoel from the ectoderm.

lxCells of a specific kind can be distributed evenly over a region by a simple device. As cells in the region all face some condition that tends to open up the special genes, the cell to do it first sends out a protein that signals its neighbors to refrain. Thus, a scattering of cells at different locations are determined.

lxiIt might seem that parallel nerves could be fused along the whole length of the body if they ran on the dorsal, rather than ventral side, where the mouth is. But that would not integrate the longitudinal nerves, which use telesensory organs to guide locomotion, with the nerve net around the mouth, which generates the feeding behavior. Thus, a ventral location was probably locked in with the evolution of gastrulation, and neither the anterior nor the posterior ganglia could be dropped since the mouth was originally located in the middle of the longitudinal gradient.

lxiiIn higher chordates, cells at the edge of the neural plate, called the neural crest, break off before the neural tube is complete and become sensory neurons or neurons serving the viscera. â In most of the body, the neural tube encloses a canal (the central canal of the spinal chord). But toward the end opposite the blastopore, where the mouth eventually forms, the neural tube swells slightly, the two sides of the neural plate do not close as a tube, and they are separated by ventricles. This is where the brain forms in vertebrates. The somatosensory chordate, Amphioxus, has no brain and the central canal remains open to the outside.

lxiiiThe acorn worm (Enteropneusta) is a large, worm that burrows in the sand. Although it lacks a notochord, which accompanies the formation of the neural tube in all other cases, which are segmented, it has neural tube dorsal to its mouth followed by a solid nerve chord that runs through the remainder of the body. And lying just beneath the ectoderm over most of its body is a plexus of neurons. But the neural tube is the center of its behavior guidance system: It selects the kind of behavior for each situation, insofar as it has whole-body behavior at all.

lxivAs noted, one minor exception is the tiny arrow worm, chaetognatha.

lxvThere are two exceptions in human brains, including the cells from which the striatum and amygdala (the basal ganglia) in the forebrain form and certain cells in the cerebellum.

lxviWhen neurons are determined by the neurons with which they synapse after having migrated or constructed processes, the way of determining the cells is to allow those that do not make synapses die. Thus, the development of the brain involves the weeding out of cells after they have tried to make connections as well as determining them before they begin.

lxviiThe subsequent evolution of the neocortex shifts the position of the hippocampus (at the extreme medial edge of what was the non-mammalian dorsal cortex) and the amygdala (originally in the ventral telencephalon) to a region of the temporal lobe.

lxviiiThere are usually several somatosensory images, registering mostly different kinds of input, such skin receptors or receptors in muscles and joints.

lxixIt is essential that these projections preserve their 2-D order, for the information they pass is essentially a 2-D "image": the information contained in the firing of each neuron depends on its relationship to the others in the 2-D array that are also firing. This is true not only in the somatotopic representation of the body, but also in the visual system, where the images are pictures taken from the 2-D array of the retina. The "images" in the 2-D arrays may, however, be abstract. The importance of the 2-D array is evident in the fine structure of the neocortex, where local synapses are mainly between cells in different layers in a "column" or with cells in nearby columns.

lxxThis illustrates a general principle (called "reentry") about the result of processing the input projected by thalamic neurons onto the neocortex. The structure of the basic mechanisms in the mammalian forebrain is the passage of information from one 2 .D area of the neocortex to another, either directly or indirectly by a thalamic relay. Since the results of processing in one area are available to other areas, the neocortex can learn to respond in the same way to any of a variety of related sensory inputs. If synapses of projections from one area to another are strengthened when the neurons they connect tend to fire at the same time, then, later, the global response will be the same, even when only some areas are active. For example, visual input from the same object is relayed to the neocortex by two nuclei, one a direct relay from the retina and the other an indirect relay from the optic tectum in the midbrain (superior colliculus in mammals), and as images are projected directly from one neocortical area to another or relayed by thalamic nuclei to other areas of neocortex, as many as fifteen or twenty different 2 .D arrays are involved in the processing. Assuming that each area is genetically disposed to respond to visual input in different ways (such as detecting line orientation, edges, corners, colors, etc.), "reentrant" connections would give the areas a joint response that is specific to certain features of the objects themselves, even though they can appear in different ways. And it can recognize particular objects with surprisingly little sensory data. (See Edelman, 1987, 1988, 1989.)

lxxiThe representation of the scene may not be exactly a picture, because the locations of objects in the scene can be given by polar coordinates relative to the body that are coded somehow in the inferior parietal cortex.

lxxiiThe pulvinar could indicate possible targets of fixations, because as the thalamic nucleus whose normal targets are visual and auditory association areas in the inferior parietal lobe, it must contain a representation of the scene. The frontal eye fields are a motor area with a separate pathway for its output through the corpus striatum (via the covert pathway, so that the eyes can still fixate while imagining behavior without behaving overtly), and they report their activities to the inferior parietal lobe, where visual images are assembled as a representation of the current scene as a whole.

lxxiiiExteroception is usually defined in a way that includes both telesensory and extrasensory input about objects in space.

lxxivLocal connections among simultaneously active neurons are probably responsible for the learning of motor skills, habits, and sensory analysis, or what is called "implicit memory". "Explicit memory" refers to the memory of events, locations of objects, and other facts, and it depends on the hippocampal memory circuit described here, because neurons in all parts of the neocortex must be connected.

lxxvThe hippocampus is a long, rolled-up edge of the ancient medial cortex. Different areas of neocortex project (by way of the temporal lobe staging area) to different points along the length of the hippocampus, and the circuit is completed by way of the relay of hippocampal output to the cingulate gyrus and its connections to each of those areas of neocortex. Relevant neurons of neocortical areas serving as the local image, the behavioral output system and behavioral schemata In the frontal cortex) may be included in the memory group by how this circuit synchronizes the formation of synapses. This is apparently the function of the so-called "theta rhythm" set up in the hippocampal circuit by the septum, for it makes all the neurons that are active at the moment part of the same memory group.

lxxviThere is abundant evidence that already established memories can be accessed after damage to the hippocampus, while it is no longer possible to lay down new memories. See Winson (1985) and Gallistel (1990, Ch. 16).

lxxviiThis is not to say that the same mechanism for linking images in sequences is not used for other purposes, for example, to represent temporal sequences of images representing the behavior of other animals. No doubt many functions are found for the capacity to link images in sequences. Edelman's (1989) notion of "recategorization" recognizes the temporal aspect of the sequencing, but he does not recognize how it is used as a 3 .D map.

lxxviiiTelesensory areas also project directly to the premotor area, presumably to fine tune motor responses to the object.

lxxixThis function is evident in the wiring of the corpus striatum: the putamen (assembling an image of the body) and the caudate nucleus (assembling an image of the object) have no direct connections to one another, but both send fibers to (both the external and internal segments of) the globus pallidus, whose internal segment supplies of the corpus striatum's two projections to thalamic nuclei for relay to frontal neocortex. However, the caudate nucleus and putamen both receive projections from the behavioral output system, so they can coordinated.

lxxxOne pathway is through the hypothalamus, a (ventral) part of the diencephalon, which has multiple connections to the midbrain. A second pathway is through the amygdala, another nucleus in the telencephalon, which, as the seat of fear, can override other routines and generate fighting or fleeing instead. And there is a third pathway involving the septum, a ventral part of the telencephalon. In primitive vertebrates, the main route for affecting the midbrain is via the habenulae, a prominent, asymmetric pair of nuclei located just above the diencephalon (or atop the dorsal thalamus) which has a heavily myelinated bundle of fibers (the fasciculus retroflexus) that passes through the thalamus to a spiral shaped nucleus at the ventral midline of the midbrain (the interpeduncular nucleus). The olfactory bulb projects to the hypothalamus and the septum (which are interconnected), and they have connections to the habenulae via the stria medularis. The amygdala (which is also connected to the hypothalamus) has a connection of its own to the habenulae via the stria terminalis. See the diagram of the olfactory selection system in the discussion of the structure of the non-mammalian brain.

lxxxiThe amygdala is displaced from its location adjacent to the striatum in non-mammalian vertebrates to the temporal lobe by the evolution of the relatively enormous neocortex.

lxxxiiThe centromedian nucleus can even control both hemispheres of the forebrain, because it is connected to its counterpart in the other hemisphere of the brain by way of special bridge (the nucleus reuniens) across the third ventricle, which separates the thalamus of each hemisphere of the forebrain.

lxxxiiiIn the avian brain, the dorsal cortex contains a detailed visual image called the "visual Wulst" which controls locomotion by its own, direct motor output. It is part of a memory map that uses visual input relayed by the thalamus directly from the retina to the dorsal cortex. And as part of the dorsal cortex, the Wulst connects through the medial cortex/hippocampus and fornix back to the mammillary body in the hypothalamus. But instead of merely influencing the midbrain and motor output, as in other non-mammals, the mammillary body relays a signal, by way of the thalamus, back to the Wulst in the telencephalon. This is a complete circuit, resembling the mammalian memory mechanism, and it is apparently used to construct a memory map for guiding locomotion. Assuming that it works the same way as in mammals, the Wulst can use a one-dimensional chain of stimulus-response connections as a map to guide locomotion without involving the rest of the circuit (hippocampus, fornix and mammillary body). But vision is the only sensory modality involved, and judging by the neurological mechanisms, it cannot use its memory map as a locomotor imagination.

lxxxivAlthough olfaction contributes to mammalian memory in the same way, this telesensory input is still analyzed in the olfactory bulb, rather than the neocortex, and thus, images of odors cannot be called up in imagination in the same way as visual and auditory images.

lxxxvThe exclusion in the other direction is not so strict, for there are several projections from the object representation in the posterior neocortex to the putamen, which otherwise receives the image of the body and the schemata from the anterior neocortex.

lxxxviNot only do lesions to the prefrontal neocortex of higher primates impair delayed spatial responses, but the role of the inferior parietal lobe in marking targets for schemata of behavior has also been confirmed by the discovery of cells in its visual arrays that fire only when behavior is being set up in relation to the object they represent. See Eric R. Kandel and James H. Schwartz (1981, pp. 582-585).

lxxxviiSee A. Brodal, 1981, pp. 839-841. Inferior parietal lesions also may cause difficulties in orienting oneself to objects on the contralateral side of their body, finding routes among them, and even distinguishing right from left.

lxxxviiiSee J. M. Van Buren and R. C. Borke, 1972, p. 151.

lxxxixIn higher animals, dominance battles between leaders of coalitions within the group may determine the relative standing of members of those subgroups. In a similar way, ritualized testing of boundaries allows groups of animals to respect one another’s territories for acquiring energy-rich objects.

xcPheromones are not the only mechanism of coordination. As we have already noted, the energy-gathering class in colonies of honey bees communicates to one another the direction and distance of energy sources by a dance that anticipates the locomotion required to travel there.

xciInsect colonies are not completely sedentary. It is sometimes possible for some of them to move the hive, queen and all, from one location to another. But no choices about the behavior of the society as a whole can be made until the new hive is set up, for that is the behavior guidance system for the behavior of the multisomatic organism.

xciiSuch incompatible desires towards objects of basically the same kind required special mechanisms to avoid the enormous harm caused by attaching them to the wrong objects. This may have been the stage at which the ability to cry evolved, particularly in women and children, for it could be a mechanism for suppressing the violent dispositions of males disposed toward violence. Their mates and offspring were otherwise helpless in the face of male anger.

xciiiFor a report of these studies, see Science News, Vol. 144, July 17, 1993, pp. 40-42, reporting a discussion in the March, 1993, issue of Behavioral and Brain Sciences.

xcivThe notion that culture involves a process that resemble biological evolution is not new, but how such change is caused and where it leads depends on one’s explanation of biological evolution. The received theory was originally advanced by Dawkins (1976), and it embodies the mistakes of accidentalism. What is evolving, according to Dawkins (1976), are “memes,” which are supposed to be analogous to genes. Memes are any item that can be learned by members of a society, such as “tunes, ideas, catch-phrases, clothes fashions, ways of making pots or of building arches,” and they reproduce simply by “imitation” (p. 206). Natural selection is by reproduction, which occurs when they are imitated. But unlike arguments, whose non-reproductive work is how they guide behavior in controlling relevant conditions, Dawkins see natural selection depending simply on whichever memes happen (accidentally!) to be able to replicate better. He suggests that memes may be selected by “psychological appeal” (207) or “how much time people spend in actively transmitting it to other people” (p. 213), but he has little to say about the criterion of selection, except to insist that it has nothing to do with “biological advantage” (pp. 207-8). Thus, though culture may change, there is no reason to believe that it will change in any specific direction. Accidentalists do not suspect that anything is missing, But arguments differ from memes, because in addition to reproducing from one brain to another, they are structural causes of behavior (and belief) and it is not just chance which arguments succeed in reproducing themselves in other brains. Arguments do non-reproductive work, and being judged by their coherence, they are selected for guiding behavior toward goals. Such rational selection of arguments that cohere with other goals and beliefs tends to make culture evolve in the direction of knowing the good and the true. Instead of accidentalism, again, evolution by reproductive causation is progressive.

xcvThis is not only Aristotle’s view of the good life, but also what Kant assumed in speaking of “counsels of prudence” which tend to produce happiness in the Foundations of the Metaphysics of Morals.

xcviPunishment is less effective in the case of crimes by members of gangs, because in that case, the offender is already submitting to the authority of some culture. Nor does punishment work effectively in philosophical cultures, like ours, in which it is coming to be recognized that there is no valid argument for taking morality as prior to self interest. As that becomes widely believed, the mechanism of morality in reflective spirits may become dysfunctional.

xcviiAmong other places, Hume uses the billiard ball example in Section IV, Part I of An Enquiy Concerning Human Understanding.

xcviiiAlthough the notion of self-organizing systems comes from thermodynamics, it has uses in biology, as is clear in Kauffman (1993).

xcixSee for example, Manicas (1987).

cMandelbaum (1971, pp. 20-28 and p. 291) discusses various forms of monistic holism or emergentism, including Engels. Engels denied the adequacy of reductionistic materialism in all branches of natural science, not just history, claiming that the basic laws of nature were not those of physics, but rather dialectical laws, in which essentially novel phenomena arise from the "contradictions" in established processes.

ciFor a popular exposition, see James Gleick, 1987.

ciiL. Sklar (1992) reviews these issues and gives references to the literature in Chapter 3, “The Introduction of Probability into Physics”. He puts the problem of reducing them to the basic laws of physics as being unable to show that the probabilistic assumptions of statistical mechanics are “nonautonomous” (p. 121). See also Sklar (1993)).

ciiiLoschmidt’s paradox does not mean that Boltzmann’s statistical explanation of this tendency is falsified by observation, for it can be held that the reason we never observe random systems spontaneously becoming nonrandom is that the random microstates that lead to nonrandom states are statistically so overwhelmingly improbable that they virtually never occur in nature. And the reason why we do observe many cases of nonrandom states becoming random can be explained by the existence of other kinds of processes in nature that impose nonrandom initial states on closed systems. This bias in our sample of systems makes what is just an atemporal statistical fact about such systems appear to be a tendency to become more random over time.

This may save the appearances, but it does not salvage Boltzmann’s definition of randomness as an explanation of the tendency to randomness. To be sure, there are sources of usable, or “free”, energy in nature that can impose nonrandom initial states on closed systems, and a more general version of the second law of thermodynamics would have to cover the systems of which they are parts. These sources of free energy include not only other systems with nonrandom distributions of elasticly interacting objects, but also systems in which the objects have potential energy because of forces they exert on one another. But their existence does not explain the tendency to randomness as a change with a direction in time. It only explains why there are so many examples of that tendency in our surroundings. There is still no reason to believe that systems that start off in a nonrandom state will become random, except that most such systems examined must be in a random state, if all possible microstates are equally probable. At best, the existence of natural processes that impose nonrandom initial states on closed systems will so bias our sample that it will appear that change has a direction in time. But that is no part of the statistical explanation of the tendency to randomness, for if its statistics did take into account the existence of such natural processes, it could not assume that all possible microstates are equally probable.

civAttempts to show the equiprobability of all possible microstates introduce another kind of phase space to represent the microstates of the gas. The position and momentum of each molecule in a box can be represented by six numbers, three each for its position and momentum, and since the state of the whole box can be represented by six numbers for each molecule, it is possible to think of the microstate of the box as the location of a single point in a “space” whose number of dimensions is six times the number of molecules. This is misleadingly similar to the real, three dimensional space from which it abstracts, for changes in the state of the box, which actually depend on the molecules all moving and interacting in real space according to the laws of physics, are represented as the “motion” of this “phase point” in a “phase space” with an enormous number of dimensions (the limits of the phase space being determined by the total energy of the gas and the size of its container). Although it can be shown that the phase point will not move around to every point, it can be shown that it will eventually spend the same amount of time in every small region of this phase space. This theorem (the ergodic theorem) is used to justify the assumption that all the points in phase space are equally probable. But as long as it shows only that the phase point will visit every region of phase space equally often, and not every point, there is no good reason to believe that the kinds of random microstates that would lead to non-random states will ever occur, because there is no reason to believe that minor differences in micro states will not add up to big differences, such as not being non-random on the macro level. The importance of such small differences is an example of the “butterfly effect” to which chaos theorists have recently been drawing attention. See J. Gleick, Chaos: The Making of a New Science (New York: Penguin Books, 1987).

cv“Philosophy and Our Mental Life”, Putnam (1975, pp. 295-6). Putnam (1978, pp. 42-3) calls it the “Laplacean super-mind’s deduction”.

cviFor Putnam (1975, pp. 296-7), structural features are singled out because of our interests, because of what is salient from our special point of view, or because of the “purposes for which we use the notion of explanation”, rather than because of the role of material structures in constituting global regularities about change over time.

cviiFor many chemical interactions, the molecules must collide with enough energy to distort one another’s geometrical structures so that their parts are in a position to exert the forces that result in exchanging parts of themselves with one another, and thus, the likelihood of such reactions depends on the mean kinetic energy of their random motion and interaction, or temperature. Although combustion does not start spontaneously, once it does start, it can be self-sustaining. Once some molecules interact energetically enough to form the stronger, lower-energy bonds, they release enough energy to put other molecules in a position to do the same.

cviiiPutnam also uses this argument elsewhere, for example, in Putnam (1992, p. 62).

cixPutnam, 1987, p. 11.

cxSee also Kauffman (1993, 1995).

cxiThe more elaborate examples in which one kind of chemical reaction is followed by another in cycles can also be explained as global regularities, for they are simply cases in which the free energy of the thermodynamic processes to be structured is supplied by the forces exerted by the molecules in the region on one another and the chemical interactions are changing the kinds of molecules that are present in the region.

cxiiSee Gleick (1987).

cxiiiJohn Post (1987) re-defines "physicalism" as a kind of materialist ontology that rejects reductionism in favor of what are, in effect, supervenient properties, and he goes so far as to take that anti-reductionism as the main reason for accepting it.

cxivA good statement of the etiological theory is given by Larry Wright (1973, 1976), but see also Michael Ruse (1973). For a criticism of the etiological theory and a defense of what they call the "propensity theory", see Bigelow and Pargetter (1987). Karen Neander (1991) defends the etiological theory against their criticisms, but in a way that is not very convincing, at least, not to me.

cxvFranz Brentano originally proposed intentionality as the distinctive mark of the mental. He focused on what he called "intentional inexistence", by which he meant that a mental state could be about something even if that something did not really exist. That rules out explaining the content of a mental state as an actual relationship to what it is about, but the content can be explained by a theory that holds that particular representations are part of a system. (Brentano did not require that all psychological states are about things that do not exist). If there is a systematic or normal relationship between representations of all types and kinds of objects/states in the world, then tokens of those types can stand for objects or states that do not exist.

cxviThis is the position long defended by D. C. Dennett (1971, reprinted in 1978). Not only does he take psychological states to be something that we ascribe to objects from the "intentional stance", but he also takes functions to be something we ascribe from the "design stance" and mechanisms to be something that we ascribe from the "physical stance". Dennett can be happy with such a position, because he is still basically an subjectivistic epistemologist, who is content to explain nature in terms of our ways of knowing about it, rather than ontologically.

cxviiIt does not help to say that there are no intentional psychological states, only words and sentences that refer to the natural world, because the same problem then arises about language. See the discussion of the problems of cotemporary analytic philosophy in Stage 10 on philosophical spiritual animals.

cxviiiSee Putnam's (1975) 1960's papers on psychology and Fodor (1975).

cxixFodor (1975) was among the first to distinguish token-token reductions from type-type reductions.

cxxSee "Individualism and Supervenience" in Fodor (1988) and Fodor (1991).

cxxiSuch a causal theory of reference is defended in Fodor 1988, Chapter 4.

cxxiiFor example, Putnam points out in "Why There Isn't a Ready-Made World" (1983, pp. 205-228) and (1981) that the kind of causal relation Fodor uses to explain references to objects/states cannot be explained by internal realism in terms of materialism. See the discussion of contemporary analytic philosophy in Stage 10.

cxxiiiFodor dismisses the possibility "that brain states should be relationally individuated" as "plain silly."

cxxivMillikan (1989, p. 283) holds that what is required to "fly a naturalist theory of content" is an "appeal to teleology" in which "what makes a thing into an inner representation is, near enough, that its function is to represent". Millikan uses an etiological analysis of functional explanations, and I have simplified her analysis somewhat, because we are interested only in representations that were naturally selected in the course of evolution. We will take up language in the next part. Van Gulick (1980) is an earlier attempt to formulate a teleological theory of representation.

cxxvMillikan (1989, pp. 290-91) uses this example from Dretske (1990) to illustrate her theory.

cxxviIn arguing against the causal theory of reference, Matthen (1988) uses, in effect, the input function of a behavior guidance system to illustrate functional explanations of the correspondence to external conditions, but he focuses on representations of color rather than the representations of objects in space on which such perception depends.

cxxviiMethodological individualism was originally defended by Karl Popper (1950, 1957), F. A. Hayek (1952), and J. W. N. Watkins (1952, 1955, 1958 and 1959). It has been criticized by Maurice Mandelbaum (1959), and more recently by David-Hillel Ruben (1985) and Margaret Gilbert (1989).

cxxviiiMoore is not unaware of this aspect of goodness. According to his principle of organic unities, (Principia Ethica, Ch. 1, Sec. 18-23) a whole may have an intrinsic value different in amount from the sum of the values of its parts.