Thesis: Human intelligence entails a layered system where each level constrains (and is constrained by) the others.

Layer 1 — Statistics (priors & uncertainty)

Example: You expect dropped objects to fall because your priors encode everyday physics (gravity, friction), not merely patterns of words.


Layer 2 — Structure (frames, invariances, constraints)

This is the grammar of worlds—what can vary and what must stay fixed.


Layer 3 — Inference (logic, planning, explanation)

Example: Orbital reasoning works because dynamics and conservation laws bound the allowable inferences.


Layer 4 — Objectives (values, costs, interfaces)