My Iranian teacher told us this joke one day. Those of us who understood it were somewhat uncomfortable.
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There was a psychiatrist who worked at his local insane asylum, prescribing medicine and discussing phobias. He liked it all very much with one exception: every morning he spent half an hour conducting a group session with unruly patients. One day he decided to see how they would respond to art therapy.
He walked in and handed each patient a piece of paper and some charcoal.
"Do whatever you want. Express yourself!" The bewildered patients looked at one another for a moment before the first leaped up and threw his charcoal at the wall, screaming that it knew his secrets.
Patient Two took the opportunity to pocket his own charcoal as well as Patient One's charcoal. He then started stuffing all the paper in the room down his pants.
Patient Three stood in the middle of the room smiling benignly. When the doctor asked him what he wanted to do with his charcoal, Patient Three put it on top of his head, dropped his pants, and yelled "Smoke the hookah!"