diff --git a/src/Plugin/Condition/Php.php b/src/Plugin/Condition/Php.php
index ca13a5a..df445bb 100644
--- a/src/Plugin/Condition/Php.php
+++ b/src/Plugin/Condition/Php.php
@@ -69,7 +69,11 @@ class Php extends ConditionPluginBase {
    * {@inheritdoc}
    */
   public function evaluate() {
-    return php_eval($this->configuration['php']);
+    $php = trim($this->configuration['php']);
+    if(!empty($php)){
+      return php_eval($this->configuration['php']);
+    }
+    return true;
   }
 
 }