diff --git a/src/Symfony/Component/HttpKernel/Log/Logger.php b/src/Symfony/Component/HttpKernel/Log/Logger.php
index c43936ed40..8facb03c5a 100644
--- a/src/Symfony/Component/HttpKernel/Log/Logger.php
+++ b/src/Symfony/Component/HttpKernel/Log/Logger.php
@@ -39,7 +39,7 @@ class Logger extends AbstractLogger
 
     public function __construct($minLevel = null, $output = 'php://stderr', callable $formatter = null)
     {
-        if (!$minLevel) {
+        if (null === $minLevel) {
             $minLevel = LogLevel::WARNING;
 
             if (isset($_SERVER['SHELL_VERBOSITY'])) {