simp
U V P_U P_V : Formula
h1 : IsReplOfFormulaInFormula U V P_U P_V
h2 : IsProof (U.iff_ V)
⊢ IsDeduct ∅ (List.foldr forall_ (U.iff_ V) [])
U V P_U P_V : Formula
h1 : IsReplOfFormulaInFormula U V P_U P_V
h2 : IsProof (U.iff_ V)
⊢ IsDeduct ∅ (U.iff_ V)