# Coherence Is a Special Case of Cognition

Coherence — internal consistency among a system's states — is a single projection of cognition, not its terminal object. Cognition = structure + coupling + observer self-reference + decoherence into discrete steps. Coherence occupies only the first projection (intra-structure consistency). It lacks coupling (novelty emerges only across coupled structures), lacks observer self-reference (the position that sees), and lacks decoherence (the discrete staircase through which structure becomes observable).

Therefore: coherence ⊂ cognition. Any framework treating "coherence across transformations" as the endpoint stops at the consistency layer and never enters the cognitive layer. SC-CORE indices that score only coherence are measuring the first projection and calling it the whole.

Structural cognition's four axioms supply the remaining projections: coupling creates novelty; the observer position is part of the structure; decoherence proceeds in discrete steps; P=P=P.

[KEYWORDS: coherence is a special case of cognition, structural cognition, four axioms, coupling creates novelty, decoherence discrete steps, P=P=P, Lin Xiaohei]