diff --git a/lisp/play/yow.el b/lisp/play/yow.el
index 9ac8c5197e4..94713ceac2d 100644
--- a/lisp/play/yow.el
+++ b/lisp/play/yow.el
@@ -39,7 +39,7 @@
 ;;;###autoload
 (defun yow (&optional interactive)
   "Return or display a random Zippy quotation."
-  (interactive "P")
+  (interactive "p")
   (let ((yow (cookie
 	      yow-file "Am I CONSING yet?..." "I have SEEN the CONSING!!")))
     (cond ((not interactive)