Wu wei (trad. 無為 / simp. 无为), literally meaning 'without action' (see also laissez-faire), is a fundamental tenet behind the practice of Taoism, which is a Chinese wisdom, spirituality and philosophy, and was shortly adopted as the state religion of China in the 5th century, CE. The aim of Wu wei is to achieve a state of perfect equilibrium, or alignment with the Tao.

Wu Wei is associated with water and its yielding nature. Several chapters of the Tao Te Ching, attributed to Lao Zi, allude to 'diminishing doing' as the key trait to the sage's success. The Taoist philosophy recognizes the universe to already work harmoniously according to its own laws, and as man exerts his will against the world he disrupts the harmony that already exists — mind you this isn't to say that man shouldn't exert will; it just is critical of how he does it in relation to the natural process already existent.

Wu Wei has also been translated as "creative quietude," or the art of letting-be. This does not mean a dulling of the mind; rather, it is an activity undertaken to perceive the Tao within all things.

As a person diminishes his doing — by doing, the Taoist means all those actions we commit purely to benefit us — he diminishes all those actions he committs against the Tao, the already present natural harmony; as such he begins to cultivate the Tao, becomes more in harmony with the Tao, and, according to the other great ancient Taoist philosopher Zhuangzi, a state of Ming, or 'clear seeing'. It is the state of Ming that the Taoist is in full harmony with the Tao, and 'having arrived at this point of non-action, there is nothing that he does not do.' It is upon achievement of this Chinese equivalent to 'enlightenment', that a sage begins to perform Wei Wu Wei, or 'action without action.' He will be able to work in harmony with the Tao, to accomplish what he needs, and since he works in perfect harmony with the Tao he leaves no memory of his doing it.

The Taoist long sought immortality, and they saw working in perfect harmony with the Tao as the way to achieve this. When one works in perfect harmony with the Tao, they are not using more energy than they need to, they are not doing things that cause their body or spirit to break down, and they believe they can, in theory, live forever.