diff --git a/STL_Extension/include/CGAL/Uncertain.h b/STL_Extension/include/CGAL/Uncertain.h
index d68508a820d..99133df0c31 100644
--- a/STL_Extension/include/CGAL/Uncertain.h
+++ b/STL_Extension/include/CGAL/Uncertain.h
@@ -275,37 +275,37 @@ Uncertain<bool> operator!(Uncertain<bool> a)
 inline
 Uncertain<bool> operator|(Uncertain<bool> a, Uncertain<bool> b)
 {
-  return Uncertain<bool>(a.inf() || b.inf(), a.sup() || b.sup());
+  return Uncertain<bool>(a.inf() | b.inf(), a.sup() | b.sup());
 }
 
 inline
 Uncertain<bool> operator|(bool a, Uncertain<bool> b)
 {
-  return Uncertain<bool>(a || b.inf(), a || b.sup());
+  return Uncertain<bool>(a | b.inf(), a | b.sup());
 }
 
 inline
 Uncertain<bool> operator|(Uncertain<bool> a, bool b)
 {
-  return Uncertain<bool>(a.inf() || b, a.sup() || b);
+  return Uncertain<bool>(a.inf() | b, a.sup() | b);
 }
 
 inline
 Uncertain<bool> operator&(Uncertain<bool> a, Uncertain<bool> b)
 {
-  return Uncertain<bool>(a.inf() && b.inf(), a.sup() && b.sup());
+  return Uncertain<bool>(a.inf() & b.inf(), a.sup() & b.sup());
 }
 
 inline
 Uncertain<bool> operator&(bool a, Uncertain<bool> b)
 {
-  return Uncertain<bool>(a && b.inf(), a && b.sup());
+  return Uncertain<bool>(a & b.inf(), a & b.sup());
 }
 
 inline
 Uncertain<bool> operator&(Uncertain<bool> a, bool b)
 {
-  return Uncertain<bool>(a.inf() && b, a.sup() && b);
+  return Uncertain<bool>(a.inf() & b, a.sup() & b);
 }