proposition: Lemma trans_trans b (phi : form b) A : A ⊢I ((dnQ (trans phi)) → trans phi).
proof: Proof. specialize (trans_trans' phi A var var). rewrite subst_var. intros H. apply (Weak H). clear H. induction A; cbn; trivial. setoid_rewrite subst_var. auto. Qed.
imports: Undecidability.PCP(PCP Util.PCP_facts) Undecidability.FOL(Deduction.FragmentNDFacts Semantics.Tarski.FragmentFacts Semantics.Tarski.FragmentSoundness Syntax.Core Syntax.Facts) Undecidability.FOL(FOL) Undecidability.Synthetic(Definitions DecidabilityFacts EnumerabilityFacts ReducibilityFacts MoreReducibilityFacts) Undecidability.FOL.Reductions.PCPb_to_FOL Undecidability.PCP.Reductions.PCPb_iff_dPCPb List Undecidability(Shared.ListAutomation)