diff --git a/attributs.py b/attributs.py
index 7fb0545..36f1bb6 100644
--- a/attributs.py
+++ b/attributs.py
@@ -573,7 +573,7 @@ class generalizedTimeFormat(Attr):
         return int(self._stamp)
 
     def __eq__(self, othertime):
-        if isinstance(self, othertime):
+        if isinstance(othertime, generalizedTimeFormat):
             return self._stamp == othertime._stamp
         else:
             resource = generalizedTimeFormat(othertime, conn=None, Parent=None)