diff --git a/src/Gica/Types/Set.php b/src/Gica/Types/Set.php
index <HASH>..<HASH> 100644
--- a/src/Gica/Types/Set.php
+++ b/src/Gica/Types/Set.php
@@ -149,7 +149,7 @@ abstract class Set
 
     public function diff(?self $other)
     {
-        $primitives = $this->primitiveValues;
+        $primitives = [];
 
         if ($other) {
             foreach ($this->primitiveValues as $primitiveValue) {
repaired bug in \Gica\Types\Set::diff