westernCanon_length
plain-language theorem explainer
The theorem fixes the length of the explicit list of Western art styles at exactly eleven. Modelers of style succession from J-cost would cite it to anchor the structural count before computing average gaps. The proof is a direct computational decision on the enumerated list definition.
Claim. The ordered list of eleven named Western art styles has length eleven.
background
The module derives visual-style succession from the J-cost trajectory of geometric coherence. It defines the Western canon as the explicit list of eleven styles with approximate emergence years (Renaissance at 1400 through Post-Modernist), then computes inter-style gaps predicted to lie in the gap-45 band. The gap itself is the product of closure and Fibonacci factors, with the display form F(Z) = ln(1 + Z/φ)/ln(φ) supplied by the anchor residue functions.
proof idea
The proof is a one-line wrapper that applies the decide tactic to evaluate the length of the concrete list westernCanon.
why it matters
It supplies the canon length to the parent theorem art_history_one_statement, which asserts eleven styles with average gap 56 yr inside the gap-45 band. The result fills the structural count step in the Track I9 derivation of style succession from J-cost, consistent with the phi-ladder and eight-tick octave of the Recognition framework.
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