ombuddha:

Caoshan asked Venerable Qiang, “The true body of Buddha is like vast emptiness. When a thing appears there, it is like the moon reflected in water. How would you express this teaching?”
Qiang said, “It’s like a donkey looking into a well.”
Caoshan said, “You’ve said a lot, but you’ve only gotten eighty percent of it.”
Qiang said, “What would you say, Master?”
Caoshan said, “It’s like the well looking at the donkey.”

From Zen’s Chinese Heritage.

Photo by Kellie C.