koan
     n : a paradoxical annecdote or a riddle that has no solution;
         used in zen buddhism to show the inadequacy of logical
         reasoning

koan /koh'an/ n. a zen teaching riddle. classically, koans are
   attractive paradoxes to be meditated on; their purpose is to help one to
   enlightenment by temporarily jamming normal cognitive processing so that
   something more interesting can happen this practice is associated with
   rinzai zen buddhism. defined here because hackers are very fond of the
   koan form and compose their own koans for humorous and/or enlightening
   effect. see some ai koans, has the x nature, hacker humor.


see also:
some ai koans has the x nature hacker humor