Chapter 17: The Structure τ: Signature, Axioms, Rigidity

The kernel of Category τ is presented for philosophical readers. Five generators—α, π, γ, η, ω—govern complementarity, projection, crossing, mediating recurrence, and terminal coherence respectively. Seven axioms K0–K6 constrain how these generators compose. The resulting structure is rigid: Aut(τ) = {id}, meaning there is exactly one τ, not a family of τ-like structures from which one must be selected. This chapter is not a technical recapitulation of Book I but a philosophical reading: what each generator means for ontology, what each axiom excludes, and why rigidity transforms a mathematical construction into an ontological claim.