“all we can do in Zen in the way of instruction is to indicate, or suggest, or to show the way so that one’s attention may be directed towards the goal. As to attaining the goal and taking hold of the thing itself, this must be done by one’s own hands, for nobody else can do it for one. As regards the indication, it lies everywhere. When a mind is matured for satori it tumbles over one everywhere. […] All the causes, all the conditions of satori are in the mind; they are merely waiting for the maturing. When the mind is ready for some reasons or others, a bird flies, or a bell rings, and you at once return to your original home; that is, you discover your now real self. From the very beginning,  nothing has been kept from you, it was only yourself that closed the eye to the fact. Therefore, there is in Zen nothing to explain, nothing to teach, that will add to your knowledge. Unless it grows out of yourself no knowledge is really yours, it is only a borrowed plumage.

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As far as content goes, there is none in either satori or Zen that can be described or presented or demonstrated for your intellectual appreciation. For Zen has no business with ideas, and satori is a sort of inner perception – not the perception, indeed, of a single individual object but the perception of Reality itself, so to speak.”