Bathtub test

A psychologist and patient were talking. The patient asked how do you determine if a person needs to be committed. He responded "the bathtub test" patient responded well how does that work? Psychologist said" I fill up a tub with water, then I get a cup, glass and pale and sit them on the floor" Patient responded O I get it, so if a person grabs the cup or glass to get the water from the tube, they get committed? Actually the psychologist said "the sane person just unplugs the drain".

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