What is Nondoing (wu-wei)?
Wu-wei - usually translated as nonaction, inaction or nondoing - is one of the most important Taoist concepts. When linked to the Tao, nondoing points to the actionless of Heaven, like in the following abstract from Tao-te ching:
The Tao in its regular course does nothing (for the sake of doing it), and so there is nothing which it does not do. (Legge, chap. 37)
Linked with the human behavior, nondoing refers to not forcing the things on their way, on the action without effort or going with the grain.
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Aikido is a living illustration of the Taoist nondoing concept. The practitioner is moving along with his opponent instead of resisting his attacks.
In the terms of Alan Watts nondoing is "what we mean by going with the grain, rolling with the punch, swimming with the current, trimming sails to the wind, taking the tide at its flood, and stooping to conquer." (Tao: The Watercourse Way, Pantheon Books, 1973.)