The Moth

A man goes into a dentists, and keeps running in circles, flapping his arms. The dentist says, excuse me, what are you doing ? The man says, I'm a moth, I'm a moth. The dentist says, but this is a dental surgery. The man keeps on running in circles, flapping his arms, saying, I'm a moth, I'm a moth. The dentist says, do you have any problems with your teeth ? I'm a moth, I'm a moth, says the man. The dentist says, then why are you here ? The man replies, you left your light on