Mu (negative)

In the Sinosphere, the word 無, realized in Japanese and Korean as mu and in Standard Chinese as wu,[a] meaning 'to lack' or 'without', is a key term in the vocabulary of various East Asian philosophical and religious traditions, such as Buddhism and Taoism.

This reconstructed root is widely represented in Tibeto-Burman languages; for instance, ma means 'not' in both Tibetan and Burmese.

The earliest graphs for 無 pictured a person with outstretched arms holding something (possibly sleeves, tassels, ornaments) and represented the word wu "dance; dancer".

[10] The Japanese Rinzai school classifies the Mu Kōan as hosshin 発心 "resolve to attain enlightenment", that is, appropriate for beginners seeking kenshō "to see the Buddha-nature"'.

The Book of Serenity (Chinese: 從容録; pinyin: Cóngróng lù), also known as the Book of Equanimity or more formally the Hóngzhì Chánshī Guǎnglù (Chinese: 宏智禪師廣錄), has a longer version of this koan, which adds the following to the start of the version given in the Zhaozhou Zhenji Chanshi Yulu.

The reference is to the Mahāyāna Mahāparinirvāṇa Sūtra[15] which says for example: In this light, the undisclosed store of the Tathagata is proclaimed: "All beings have the Buddha-Nature".

[17] This koan is one of several traditionally used by Rinzai school to initiate students into Zen study,[4] and interpretations of it vary widely.

[19] The Japanese scholar Iriya Yoshitaka [ja] made the following comment on the two versions of the koan: I have held doubts for some time even with regard to the way the so-called "Chao-chou's Word No" has been previously dealt with.

However, Zen adherents in Japan have rendered the koan exclusively in terms of his negative response, and completely ignored the affirmative one.

[20]A similar critique has been given by Steven Heine: The common approach espoused [...] emphasizes a particular understanding of the role of the koan based on the “head-word” or “critical phrase” method developed by the prominent twelfth century Chinese master, Daie.

[21]In Robert M. Pirsig's 1974 novel Zen and the Art of Motorcycle Maintenance, mu is translated as "no thing", saying that it meant "unask the question".

[22]The word features prominently with a similar meaning in Douglas Hofstadter's 1979 book, Gödel, Escher, Bach.