diff --git a/lib/api/traversing.js b/lib/api/traversing.js
index 5db3fa1b014..bd417beac8e 100644
--- a/lib/api/traversing.js
+++ b/lib/api/traversing.js
@@ -86,7 +86,7 @@ exports.parent = function (selector) {
     }
   });
 
-  if (arguments.length) {
+  if (selector) {
     set = exports.filter.call(set, selector, this);
   }