--- a/src/HOL/Isar_examples/Peirce.thy Fri Apr 23 11:48:37 1999 +0200
+++ b/src/HOL/Isar_examples/Peirce.thy Fri Apr 23 11:50:17 1999 +0200
@@ -2,15 +2,13 @@
ID: $Id$
Author: Markus Wenzel, TU Muenchen
-Peirce's law: some examples of classical proof.
+Peirce's law: examples of classical proof.
*)
theory Peirce = Main:;
-lemmas it[elim!] = mp notE; (* FIXME elim!! *)
-
-lemma Peirce's_law: "((A --> B) --> A) --> A";
+theorem "((A --> B) --> A) --> A";
proof;
assume ABA: "(A --> B) --> A";
show A;
@@ -28,7 +26,7 @@
qed;
-lemma Peirce's_law: "((A --> B) --> A) --> A";
+theorem "((A --> B) --> A) --> A";
proof;
assume ABA: "(A --> B) --> A";
show A;