src/ZF/AC.thy
author lcp
Tue Jul 26 13:21:20 1994 +0200 (1994-07-26)
changeset 484 70b789956bd3
child 1478 2b8c2a7547ab
permissions -rw-r--r--
Axiom of choice, cardinality results, etc.
     1 (*  Title: 	ZF/AC.thy
     2     ID:         $Id$
     3     Author: 	Lawrence C Paulson, Cambridge University Computer Laboratory
     4     Copyright   1994  University of Cambridge
     5 
     6 The Axiom of Choice
     7 
     8 This definition comes from Halmos (1960), page 59.
     9 *)
    10 
    11 AC = ZF + "func" +
    12 rules
    13   AC	"[| a: A;  !!x. x:A ==> (EX y. y:B(x)) |] ==> EX z. z : Pi(A,B)"
    14 end