theorem
proved
framework_is_reflexively_closed
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IndisputableMonolith.Foundation.UniversalForcingSelfReference on GitHub at line 216.
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213because the equivalence is `Type 1`-valued, while the conjunction here
214is propositional. The Nonempty wrapper is harmless: the equivalence
215exists for every pair, so its `Nonempty` is trivially inhabited. -/
216theorem framework_is_reflexively_closed :
217 -- Identity, non-contradiction, totality of meta-cost are automatic:
218 (∀ R : MetaCarrier, metaCost R R = 0) ∧
219 (∀ R S : MetaCarrier, metaCost R S = metaCost S R) ∧
220 (∀ R S : MetaCarrier, ∃ c : ℕ, metaCost R S = c) ∧
221 -- The meta-theorem supplies the comparison law:
222 (∀ R S : MetaCarrier, Nonempty (R.Orbit ≃ S.Orbit)) := by
223 refine ⟨metaCost_self, metaCost_symm, metaCost_total, ?_⟩
224 intro R S
225 exact ⟨metaForcedArithmeticInvariance R S⟩
226
227/-! ## The Meta-Meta-Theorem -/
228
229/-- **Meta-meta-theorem.** Applying the meta-theorem inside the
230meta-realization yields the meta-theorem again. The structure of the
231meta-theorem is preserved under self-application: comparing two
232realizations through the meta-realization gives the same canonical
233equivalence as comparing them directly through `universal_forcing`.
234
235This is the reflexive-fixed-point property: `universal_forcing` is its
236own input under the meta-realization shape. -/
237theorem meta_meta_theorem (R S : MetaCarrier) :
238 metaForcedArithmeticInvariance R S = universal_forcing_via_NNO R S :=
239 rfl
240
241/-! ## Honest acknowledgements
242
243What this module *does not* prove:
244
245* It does not prove `universal_forcing` proves itself in the
246 metalogical sense. Gödel-style self-reference would require a