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structure definition def or abbrev high

MetaphysicalGround

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MetaphysicalGround defines a structure that assigns every Law-of-Logic realization its forced arithmetic object while requiring all such objects to be canonically equivalent. Foundation researchers in Recognition Science cite it when stating the universal forcing theorem in neutral structural terms. The definition is a direct encoding of a source name plus two equivalence properties with no computational content or lemmas.

claimA metaphysical ground consists of a string source name together with the properties that, for every logic realization $R$, the Peano carrier of the arithmetic extracted from $R$ is equivalent to the logic natural numbers, and that for any two realizations $R$ and $S$ these carriers are equivalent to each other.

background

LogicRealization supplies a carrier type, a cost type equipped with zero, a comparison map, and a zero element, together with the structural laws required by the forcing program. arithmeticOf extracts from any realization the canonical arithmetic object whose Peano surface is logicNatPeano. LogicNat is the inductive type with constructors identity and step, representing the orbit under the generator that begins at the multiplicative identity and is closed under multiplication by the generator step.

proof idea

This declaration is a pure structure definition. It introduces the three fields sourceName, identifies_arithmetic, and invariant directly, with no lemmas, tactics, or reductions applied.

why it matters in Recognition Science

This definition supplies the type instantiated by universalGround to realize the canonical metaphysical ground supplied by the universal forcing theorem. It makes precise the structural claim that the source of distinguishability yields a unique arithmetic across all realizations. In the Recognition Science framework it closes the metaphysical question in the Universal Forcing paper without committing to any particular doctrine.

scope and limits

formal statement (Lean)

  25structure MetaphysicalGround where
  26  sourceName : String
  27  identifies_arithmetic :
  28    ∀ R : LogicRealization, (arithmeticOf R).peano.carrier ≃ ArithmeticFromLogic.LogicNat
  29  invariant :
  30    ∀ R S : LogicRealization, (arithmeticOf R).peano.carrier ≃ (arithmeticOf S).peano.carrier
  31
  32/-- The universal forcing theorem supplies a canonical metaphysical-ground

used by (1)

From the project-wide theorem graph. These declarations reference this one in their body.

depends on (9)

Lean names referenced from this declaration's body.