The only kind of person that actually knows what he or she is talking about.
Psychiatrist: You need medication because I believe you are mentally ill.
Philosopher: All because you believe I'm mentally ill doesn't mean I am. Isn't it just as possible that you're mentally ill believing that I'm mentally ill without any real scientific evidence to back it up?
A cursed musical instrument said to have come from the Devil.
Rich: Ahh! My ears!
John: That, my friend, is the piccolo.