:PROPERTIES: :ID: 0b5a8a74-cfd6-542d-bc88-4eb3cd8626f9 :END: #+title: Cost Structure — Zero Marginal Cost #+filetags: :passepartout:economics:cost:marginal:zero: - **One-time cost:** gate-rule encoding for a domain (from hours for codified domains up to months for tacit domains) - **Near-zero marginal cost:** ACL2 proof + Screamer consistency check + VivaceGraph lookup per interaction — all CPU-native, all in-image - **No recurring LLM API costs** for the 80% symbolic reasoning layer - **After sufficiency flip:** pennies per day vs dollars per day for LLM-only The cost curve inverts: generation is expensive, verification is cheap. This is the inversion Passepartout exploits. Token demand shifts from "every interaction burns tokens" to "only unfamiliar interactions burn tokens." Steady-state per-user LLM consumption drops by an order of magnitude. See also: [[file:lisp-economics.org][Lisp economics]], [[file:gate-rule-encoding.org][Gate rule encoding]], [[file:sufficiency-flip.org][Sufficiency flip]]