Rule not_not is now stored in theory (needed by Inductive).
--- a/src/HOL/simpdata.ML Tue Oct 05 15:23:22 1999 +0200
+++ b/src/HOL/simpdata.ML Tue Oct 05 15:24:58 1999 +0200
@@ -194,7 +194,7 @@
bind_thms ("ex_simps", ex_simps);
bind_thms ("all_simps", all_simps);
-
+bind_thm ("not_not", not_not);
(* Elimination of True from asumptions: *)