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What is the Universal Forcing theorem?

Big AI job. Grok 4.3 reads the canon and writes a Lean-grounded derivation; usually 20 seconds to 2 minutes. Your answer will appear below.
confidence: high in recognition cached

1. Setting: admissible Law-of-Logic realizations

The setting consists of admissible Law-of-Logic realizations: structures carrying a carrier type, comparison cost, identity element, step operation, and laws (identity, non-contradiction, excluded middle, composition, invariance, nontriviality) that satisfy the Law of Logic.

2. Theorem: same arithmetic structure forced across realizations

The theorem states that any two such realizations force canonically equivalent arithmetic objects; these objects are initial Peano algebras, so the equivalence is the unique isomorphism between them.

3. Cited Lean anchors

The core statement appears as universal_forcing, which asserts that for realizations R and S the carriers of their extracted Peano objects are equivalent via ArithmeticOf.equivOfInitial. This relies on the supporting definitions arithmeticOf (the forced arithmetic extracted from a realization) and arithmetic_invariant (the canonical equivalence between two realizations' arithmetic objects).

recognition modules consulted

The Recognition library is at github.com/jonwashburn/shape-of-logic. The model is restricted to the supplied Lean source and instructed not to invent theorem names. Treat output as a starting point, not a verified proof.