let set_goal = ProofEngineStructuralRules.set_goal
let simpl = ReductionTactics.simpl_tac
let split = IntroductionTactics.split_tac
-let subst = EqualityTactics.subst_tac
+let subst = SubstTactic.subst_tac
let symmetry = EqualityTactics.symmetry_tac
let transitivity = EqualityTactics.transitivity_tac
let unfold = ReductionTactics.unfold_tac