# HG changeset patch # User wenzelm # Date 924861017 -7200 # Node ID 3489490c948d069383beb2d6d6d725bab0f5d038 # Parent 937eb94b2aab8499e370ce92d623e8a13d964797 tuned; diff -r 937eb94b2aab -r 3489490c948d src/HOL/Isar_examples/Peirce.thy --- 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;