Registry · Proposition VII.P04 tau-effective formalized

VII.P04 — No-Diagonal Principle

No surjective morphism from Ob(τ³) to j-closed subobjects of presheaf category; lemniscate crossing-point constraint prevents unrestricted diagonalisation.

Book VII Part 1 Ch. 9

Dependency Graph

Depends on (1)

VII.D16

Depended on by (1)

VII.T07

Lean Formalization

Module: TauLib.BookVII.Meta.Registers

Symbol: Tau.BookVII.Meta.Registers.NodiagonalPrinciple