X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fmatita%2Flib%2Fformal_topology%2Frelations_to_o-algebra.ma;h=bc5153d5db66532004203625260f99767955eea9;hb=0460fd3dc2909efe0baa6592281d0cf0527165ff;hp=48ac80da02696d4f93a7377fbf768e3854054959;hpb=bc477154d15f6979c948f9af602199af547d193e;p=helm.git

diff --git a/matita/matita/lib/formal_topology/relations_to_o-algebra.ma b/matita/matita/lib/formal_topology/relations_to_o-algebra.ma
index 48ac80da0..bc5153d5d 100644
--- a/matita/matita/lib/formal_topology/relations_to_o-algebra.ma
+++ b/matita/matita/lib/formal_topology/relations_to_o-algebra.ma
@@ -22,9 +22,9 @@ definition POW': objs1 SET → OAlgebra.
   | apply overlaps;
   | apply big_intersects;
   | apply big_union;
-  | apply ({x | ⊤});
+  | apply ({x | True});
     simplify; intros; apply (refl1 ? (eq1 CPROP));
-  | apply ({x | ⊥});
+  | apply ({x | False});
     simplify; intros; apply (refl1 ? (eq1 CPROP));
   | intros; whd; intros; assumption
   | intros; whd; split; assumption