intros. auto.
qed.
-(*
-theorem pippo: \forall m,n. (le (S m) (S n)) \to (le m n).
+(* proof of le_gen_S_S with lapply *)
+theorem le_gen_S_S_2: \forall m,n. (le (S m) (S n)) \to (le m n).
intros.
-lapply le_gen_S_x.
-*)
+lapply le_gen_S_x to H. elim Hcut1. elim H1.
+lapply eq_gen_S_S to H2. rewrite left Hcut3. assumption.
+qed.
\ No newline at end of file