Ch'an is a direct method. It's impossible to use language or description to show the degree of clarity of one's mind. To say or do nothing at all are also out of the question, so you use any words or actions, directly and spontaneously, which are readily available. The words and actions are tools in the hands of the master, and their meanings cannot be ascertained from their conventional usage.

Phrases like, "It's raining in the east but the west gets wet, " or "Mr. Li drinks, but Mr. Lo gets drunk" are easy to understand. Words, language and concepts are all man-made artifacts. If we don't stick to the conventional meanings of words, there is no reason why a "bird" could not be a fish, or a "fish" a bird. Besides, from the point of view of unified mind, there is no coming and going of things, no distinction between this and that.

How does the Ch'an master determine the disciple's level of understanding? By asking certain questions and gauging the responses. A simple question, "Have you eaten yet?" could be answered in a number of ways. The disciple could simply say, "Yes, " or, "I've never been hungry." These are completely different responses, and might indicate different levels of experience. If the master then says, "Have you done the dishes?" and the disciple says, "I just did, " it is in fact irrelevant whether the disciple actually washed the dishes. It is the response to the question that matters. The dialogue has nothing to do with "true" or "false."