Shoyoroku - Case 52: Sozan's "Dharma-body"

Sozan asked Elder Toku, 
  "'The true Dharma-body of Buddha is like the empty sky. It manifests its
   form corresponding to things -- just like the moon on the water.' [1]
   How do you explain the principle of this corresponding?"
Toku said,
  "It is like a donkey looking into a well."
Sozan said,
  "You put it in a nice way, but you were able to say only eighty percent."
Toku said,
  "How about you, Master?"
Sozan said,
  "It is like a well looking at a donkey."

[1]: A quotation from a sutra.