How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Transitive models of fixed finite axiom fragments
Statement
For each fixed external finite , ZF proves that some transitive satisfies , with above any prescribed ordinal bound. In ZFC the analogous scheme holds for fixed finite . These are schemes indexed by external fragments, not a single internal assertion of models for all coded fragments.
Facts & Assumptions
Montague–Lévy reflection for a finite formula family: In ZF, for each fixed finite family and every ordinal , some makes absolute between and , for all tuples in . More generally the same holds between and for a definable increasing continuous hierarchy of sets exhausting a definable nonempty class . For an empty class, the relativization statement is interpreted as a scheme rather than satisfaction in an empty structure.
The set of first-order ZF axiom sentences: Let contain the codes of exactly the following six sentences, together with all instances of the two schemas below.
The Axiom of Choice: Every family of nonempty sets has a choice function
Proof
Given: A fixed external finite fragment of ZF, or of ZFC with ambient AC, and an ordinal bound.
List the finitely many sentences of using the axiom serialization in F2. Each is an axiom of the ambient theory, so their finite conjunction is a theorem there. If the ambient theory is ZFC and one of these sentences is Choice, use F3 exactly for that sentence. No Choice premise is needed for the ZF branch.
Apply F1 to that fixed finite list and the desired bound. It gives a such that each . Step 1.1 gives the right-hand sides, hence every relativized axiom. The cumulative stage is transitive, so it is the required transitive model. For an infinite carrier begin with a bound at least . For any nonempty stage above the bound works.