diff --git a/pixelocr/gui/__init__.py b/pixelocr/gui/__init__.py
index 842f7c5..6418be2 100644
--- a/pixelocr/gui/__init__.py
+++ b/pixelocr/gui/__init__.py
@@ -61,11 +61,11 @@ class WorkerThread(QThread):
     def __init__(self, document, quit=False):
         super().__init__()
         self.document = document
-        self.quit = quit
+        self._quit = quit
 
     def run(self):
         self.document.recognize()
-        if self.quit:
+        if self._quit:
             qApp.quit()