III.T04 — Canonical Ladder Theorem

The enrichment ladder E₀ ⊊ E₁ ⊊ E₂ ⊊ E₃ is (i) non-empty at each level, (ii) strictly increasing, (iii) saturating at E₃, (iv) the unique maximal enrichment chain for Category τ. It is the organising result of Book III and the architectural blueprint for the entire series.