diff --git a/src/test/py/test_logical_operations.py b/src/test/py/test_logical_operations.py
index a66258a..c21facc 100644
--- a/src/test/py/test_logical_operations.py
+++ b/src/test/py/test_logical_operations.py
@@ -18,6 +18,9 @@ class calculationsWithRoots(unittest.TestCase):
     def test_disconjunctive_identity__and_1_equals_None(self):
         self.assertEqual(identity_conjunctive(0, 1), None)
 
+    def test_disconjunctive_identity__and_1_equals_None(self):
+        self.assertEqual(identity_conjunctive(0, 0), 0)
+
 
 if __name__ == "__main__":
     unittest.main()