matitaB/matita/tests/absurd.ma

   1 (**************************************************************************)
   2 (*       ___                                                              *)
   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
   5 (*      ||T||                                                             *)
   6 (*      ||I||       Developers:                                           *)
   7 (*      ||T||         The HELM team.                                      *)
   8 (*      ||A||         http://helm.cs.unibo.it                             *)
   9 (*      \   /                                                             *)
  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
  12 (*                                                                        *)
  13 (**************************************************************************)
  14
  15
  16 include "coq.ma".
  17 alias num (instance 0) = "natural number".
  18 alias symbol "eq" (instance 0) = "Coq's leibnitz's equality".
  19 alias id "not" = "cic:/Coq/Init/Logic/not.con".
  20
  21 theorem stupid : \forall a:Prop. a \to not a \to 0 = 1.
  22 intros.
  23 absurd a.
  24 assumption.
  25 assumption.
  26 qed.