diff --git a/metropolis/pkg/event/memory/memory.go b/metropolis/pkg/event/memory/memory.go
index c684c18..7402d64 100644
--- a/metropolis/pkg/event/memory/memory.go
+++ b/metropolis/pkg/event/memory/memory.go
@@ -206,7 +206,7 @@
 		if opt.Predicate != nil {
 			predicate = opt.Predicate
 		}
-		if opt.BacklogOnly != false {
+		if opt.BacklogOnly {
 			return empty, errors.New("BacklogOnly is not implemented for memory watchers")
 		}
 	}