diff --git a/src/read.c b/src/read.c
index 69ae0f45b..753b6e6be 100644
--- a/src/read.c
+++ b/src/read.c
@@ -1435,7 +1435,7 @@ struct obj *sobj; /* scroll, or fake spellbook object for scroll-like spell */
         if (sblessed)
             do_class_genocide();
         else
-            do_genocide(!scursed | (2 * !!Confusion));
+            do_genocide((!scursed) | (2 * !!Confusion));
         break;
     case SCR_LIGHT:
         if (!confused || rn2(5)) {