Goal forall (A B : Prop) (H : A -> B), A -> A -> B. intros A B H ?%H H0. exact H1. Qed. Goal forall (A B : Prop) (H : A -> B), A -> A -> B. intros A B H ?H%H H0. exact H1. Qed. Goal forall (A B : Prop) (H : A -> B), A -> A -> B. intros A B H J%H H0. exact J. Qed. Set Mangle Names. Goal forall (A B : Prop) (H : A -> B), A -> A -> B. intros A B H ?%H _0. assumption. Qed.