proposition: Lemma extensional_eq V (M : interp V) rho : extensional M -> rho ⊫ ZF' -> rho ⊫ ZFeq'.
proof: Proof. intros H1 H2 phi [<-|[<-|[<-|[<-|H]]]]; try now apply H2. all: cbn; intros; rewrite !H1 in *; congruence. Qed.
imports: Undecidability.FOL.ZF Undecidability.FOL.Syntax.Facts Undecidability.FOL.Semantics.Tarski.FullFacts Undecidability.FOL.Sets.ZF Lia Undecidability.PCP(PCP Util.PCP_facts Reductions.PCPb_iff_dPCPb) Undecidability(Shared.ListAutomation)