+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+include "logic/connectives.ma".
+
+ninductive eq (A: Type) (a: A) : A → Prop ≝
+ refl: eq A a a.
+
+interpretation "leibnitz's equality" 'eq t x y = (eq t x y).
+
+interpretation "leibnitz's non-equality" 'neq t x y = (Not (eq t x y)).
\ No newline at end of file