this from a book I'm reading on Zen buddhism:
"Zen is not merely a cult of impulsive action. The point of mo chih ch'u is not to elimninate reflective thought but to eliminate "blocking" in both action and thought, so that the response of the mind is always like a ball in a mountain stream- 'one thought after another without hesitation'...there is a tendency to confuse 'blocking'- a purely obstructive mechanism- with thinking out an answer, but the difference between the two is easily noticed in such a purely 'thinking out' process as adding a column of figures. Many people find that at certain combinations of numbers, such as 8 and 5 or 7 and 6, a feeling of resistance comes up which halts the process. Because it is always annoying and disconcerting, one tends also to block at blocking, so that the state turns into the kind of wobbling dither characteristic of the snarled feed-back system. The simplest cure is to feel free to block, so that one does not block at blocking. When one feels free to block, the blocking automatically eliminates itself."
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'Blocking' is perhaps the best translation of the Zen term nien as it occurs in the phrase wu nien, 'no thought', or better, 'no second thought.' Takuan points out that this is the real meaning of 'attachment' in buddhism, as when it is said that a buddha is free from worldly attachments. it does not mean that he is a 'stone buddha' with no feelings, no emotions, and no sensations of hunger or pain. it means he does not block at anything."
Watts- The way of zen
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'Blocking' is perhaps the best translation of the Zen term nien as it occurs in the phrase wu nien, 'no thought', or better, 'no second thought.' Takuan points out that this is the real meaning of 'attachment' in buddhism, as when it is said that a buddha is free from worldly attachments. it does not mean that he is a 'stone buddha' with no feelings, no emotions, and no sensations of hunger or pain. it means he does not block at anything."
Watts- The way of zen