Q: How many Zen masters does it take to screw in a lightbulb?
A: <smash the lightbulb>
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OK, try again.
Q: How many Zen masters does it take to screw in a lightbulb?
A: Five. Two to argue over whether the buddha nature already resides
in the empty socket, one to light a candle instead, and two to
shovel out the outhouses.
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On a related topic:
Q: How many psychoanalysts does it take to screw in a lightbulb?