When I was a kid, and somebody said something stupid, I'd object, and then he'd say "don't be such a smartass." To which I'd reply "better a smartass than a dumbass like you."
Usually that shut them up. But sometimes it just made them louder. And oftentimes it brought on physical violence. But I could usually win a physical fight with a stupid opponent. It's hard *not* to be able to block or dodge a roundhouse punch.