At the beginning each practitioner is given a hua-tou, a kind of koan. For example: What is this? I-Mo-Ko? What is this? The idea is to concentrate your entire attention and mind on this one particular koan or hua-tou: What is this? What is this? What is this? It is different from vipassana meditation where the intention is to be aware and solely aware of what is going on. When you eat, you just acknowledge how that feels—approaching the spoon, touching the spoon, feeling the coolness of the handle, and so on. In koan meditation, however, your attention is single-pointedly directed to this question—What is this?—right now. Initially, it is very difficult to concentrate because all kinds of thinking comes up . . . comes up . . . comes up . . . like clouds, or smoke from a chimney…