diff --git a/defs.h b/defs.h
index ab03da629..acd3dc77d 100644
--- a/defs.h
+++ b/defs.h
@@ -181,8 +181,8 @@
 
 #ifndef _DEBUG
 #define assert(exp)
-#define assurance(exp, value) if (exp) return
-#define commitment(exp, value) if (exp) return false
+#define assurance(exp, value) if (!(exp)) return
+#define commitment(exp, value) if (!(exp)) return false
 #else
 #define assert(exp) (void)((exp) || (assert_fail(__LINE__, __FILE__, #exp), 0))
 #define assurance(exp, value) (void)((exp) || (app_fatal("%s: %s was %i", __func__, #exp, value), 0))