Part VII: The Hinge Theorem
The mathematical arc closes. Parts 0 through VII have built every piece of the enrichment ladder from five generators and seven axioms—the spectral algebra, the Millennium clusters, the enriched bi-square, and the computational collapse. This Part assembles the pieces into a single theorem.
The Complete Dependency Chain (Chapter 60) displays the full derivation path: five generators → seven axioms → four orbits → ABCD coordinates → boundary ring → Central Theorem (Book II) → enrichment ladder (E₀ ⊂neq E₁ ⊂neq E₂ ⊂neq E₃) → 4+1 sector template → spectral algebra → Millennium clusters → enriched bi-square → computational collapse → Hinge. Every link is earned; no postulates, no free parameters.
The Hinge Theorem (Chapter 61) states that every result in Books IV–VII is a sector instantiation of Book III’s enrichment structure. The seven-book architecture is derived, not postulated. Export contracts to all four downstream books are formalised (Chapter 62), and the No Knobs Ledger (Chapter 63) exhibits that every inter-sector coupling is canonically determined by ι_τ.
Scope throughout: τ-effective. No philosophy, no bridges—pure τ-internal mathematics closing the arc.