Mumonkan - Case 5: Kyogen Mounts the Tree

Kyogen said:
  "Zen is like a man hanging in a tree by his teeth over a precipice. His
   hands grasp no branch, his feet rest on no limb, and under the three
   another person asks him:
     'Why does Bodhidharma come to China from India?'
   If the man in the tree does not answer, he fails; and if he does answer,
   he falls and loses his life. Now what shall he do?"

Mumon's Comment:

In such a predicament the most talented eloquence is no use. If you have
memorized all the sutras, you cannot use them. When you can give the right
answer, even though your past road was one of death, you open up a new road
of life. But if you cannot answer, you should wait for ages hence and ask
Maitreya, the future Buddha.

    Kyogen is truly a fool
    Spreading that ego-killing poison
    That closes his pupils' mouths
    And lets their tears stream from their dead eyes.