Patch by Ferruccio that enables \top/\bot for False/True undone.

[helm.git] / matita / matita / lib / basics / sets.ma

diff --git a/matita/matita/lib/basics/sets.ma b/matita/matita/lib/basics/sets.ma
index 43b22bff6900c1a329610a05596c4a37b41346a6..cdc6ac9e8e278e19c3d7957bf600f7150ae1d895 100644 (file)
--- a/matita/matita/lib/basics/sets.ma
+++ b/matita/matita/lib/basics/sets.ma
@@ -13,7 +13,7 @@ include "basics/logic.ma".
 
 (**** a subset of A is just an object of type A→Prop ****)
 
-definition empty_set ≝ λA:Type[0].λa:A.⊥.
+definition empty_set ≝ λA:Type[0].λa:A.False.
 notation "\emptyv" non associative with precedence 90 for @{'empty_set}.
 interpretation "empty set" 'empty_set = (empty_set ?).