diff --git a/pyasn1/type/base.py b/pyasn1/type/base.py
index e328340d..65611897 100644
--- a/pyasn1/type/base.py
+++ b/pyasn1/type/base.py
@@ -243,9 +243,11 @@ def __ge__(self, other):
 
     if sys.version_info[0] <= 2:
         def __nonzero__(self):
+            if not self.isValue: return False
             return self._value and True or False
     else:
         def __bool__(self):
+            if not self.isValue: return False
             return self._value and True or False
 
     def __hash__(self):