--- a/src/HOL/HOL.thy Thu Jun 25 07:34:30 2009 +0200
+++ b/src/HOL/HOL.thy Thu Jun 25 14:59:29 2009 +0200
@@ -198,9 +198,6 @@
axiomatization
undefined :: 'a
-abbreviation (input)
- "arbitrary \<equiv> undefined"
-
subsubsection {* Generic classes and algebraic operations *}