During a guided tour of an asylum, a visitor asks the director how he determines whether a patient is crazy or not.
"Simple" replies the director, "we fill a bathtub with water, we give patients the choice of a spoon, a cup, or a bucket, and ask them to empty the bathtub".
"I see!" exclaims the visitor. "So obviously a sane person will choose a bucket!"
"No" says the director, "a sane person pulls the bath plug. Would you like our standard room or one with a view?"
(Hat tips to my father for the joke, and to shell belle for the picture)