simp
case a.a.h1.h1.h1.a
P_u : Formula
u v : VarName
h1_left : ¬isFreeIn v P_u
h1_right_right_left : fastAdmits u v P_u
h1_right_left : ¬isFreeIn u (fastReplaceFree u v P_u)
h1_right_right_right_left : fastAdmits v u (fastReplaceFree u v P_u)
h1_right_right_right_right_right : P_u = fastReplaceFree v u (fastReplaceFree u v P_u)
⊢ forall_ u P_u ∈ {forall_ u P_u}
no goals