diff options
Diffstat (limited to 'theories/Logic/Berardi.v')
| -rw-r--r-- | theories/Logic/Berardi.v | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/theories/Logic/Berardi.v b/theories/Logic/Berardi.v index 0fe8a87d..9eaef07a 100644 --- a/theories/Logic/Berardi.v +++ b/theories/Logic/Berardi.v @@ -6,7 +6,7 @@ (* * GNU Lesser General Public License Version 2.1 *) (************************************************************************) -(*i $Id: Berardi.v,v 1.5.2.2 2004/08/03 17:42:43 herbelin Exp $ i*) +(*i $Id: Berardi.v 8122 2006-03-04 19:26:40Z herbelin $ i*) (** This file formalizes Berardi's paradox which says that in the calculus of constructions, excluded middle (EM) and axiom of @@ -92,14 +92,10 @@ End Retracts. Lemma L1 : forall A B:Prop, retract_cond (pow A) (pow B). Proof. intros A B. -elim (EM (retract (pow A) (pow B))). -intros [f0 g0 e]. -exists f0 g0. -trivial. - -intros hf. -exists (fun (x:pow A) (y:B) => F) (fun (x:pow B) (y:A) => F). -intros; elim hf; auto. +destruct (EM (retract (pow A) (pow B))) as [(f0,g0,e) | hf]. + exists f0 g0; trivial. + exists (fun (x:pow A) (y:B) => F) (fun (x:pow B) (y:A) => F); intros; + destruct hf; auto. Qed. |