A man went to his doctor and said, "doctor, I think I'm a moth."
The doctor looked up and said, "you don't want me, you want to see the psychiatrist."
"I know I do," said the man.
"Well, his office is just down the corridor from here - right next door."
"I know it is."
"Well," says the exasperated doctor, "why did you come in here then?!"
"Your light was on!"