simp
case h1.a.a.a.h2
P Q : Formula
v : VarName
h1 : ¬isFreeIn v Q
⊢ ∀ H ∈ {forall_ v (P.imp_ Q)}, ¬isFreeIn v H
case h1.a.a.a.h2
P Q : Formula
v : VarName
h1 : ¬isFreeIn v Q
⊢ ¬isFreeIn v (forall_ v (P.imp_ Q))