+ destruct H.
+qed.
+
+inductive dt (A:Type): Type \to Type \def
+ | k1: \forall T:Type. dt A T
+ | k2: \forall T:Type. \forall T':Type. dt A (T \to T').
+
+theorem stupid3:
+ k1 False (False → True) = k2 False False True → False.
+ intros;
+ destruct H.
+qed.
+
+inductive dddt (A:Type): Type \to Type \def
+ | kkk1: dddt A nat
+ | kkk2: dddt A nat.
+
+theorem stupid4: kkk1 False = kkk2 False \to False.
+ intros;
+ destruct H.
+qed.
+
+theorem recursive: S (S (S O)) = S (S O) \to False.
+ intros;
+ destruct H.