--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||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 "convertibility.ma".
+include "types.ma".
+
+(* PURE TYPE SYSTEMS OF THE λ-CUBE ********************************************)
+
+inductive Cube_Ax: nat → nat → Prop ≝
+ | star_box: Cube_Ax 0 1
+.
+
+(* The λPω pure type system (a.k.a. λC or CC) *********************************)
+
+inductive CC_Re: nat → nat → nat → Prop ≝
+ | star_star: CC_Re 0 0 0
+ | box_star : CC_Re 1 0 0
+ | box_box : CC_Re 1 1 1
+ | star_box : CC_Re 0 1 1
+.
+
+definition CC: pts ≝ mk_pts Cube_Ax CC_Re conv.
+
+(* The λω pure type system (a.k.a. Fω) ****************************************)
+
+inductive FO_Re: nat → nat → nat → Prop ≝
+ | star_star: FO_Re 0 0 0
+ | box_star : FO_Re 1 0 0
+ | box_box : FO_Re 1 1 1
+.
+
+definition FO: pts ≝ mk_pts Cube_Ax FO_Re conv.