Two guys go into a pub. There is a swing band playing the old song "Yes, we have no bananas".
Guy 1: I love this song!
Guy 2: Yes. I think it's written by Mozart.
Guy 1: Of course it's not. They didn't make swing music in Mozart's time.
Guy 2: Yes they did!
Guy 1: You're stupid! They didn't even have bananas back then.
Guy 2: I know, that's the name of the song!