III.R04 — Enrichment Ladder Preview

Preview of the enrichment ladder: E₀ (mathematics, Books I-III), E₁ (physics, Books IV-V), E₂ (life, Book VI), E₃ (metaphysics, Book VII). Why exactly 4 layers = why 7 books. The (3,2,1,1) distribution is a mathematical consequence of the 4-orbit closure.