Photography by Denis Theval
Artwork by Joseph Szymkowiak
The Japanese and Korean term mu (Japanese: 無; Korean: 무) or Chinese wu (traditional Chinese: 無; simplified Chinese: 无) meaning "not have; without" is a key word in Buddhism, especially the Chan and Zen traditions.
The Chinese word wu 無 "not; nothing" was borrowed by East Asian languages, particularly the Sino-Xenic "CJKV" languages of Chinese, Japanese, Korean, and Vietnamese.
The Modern Standard Chinese pronunciation wu 無 historically derives from (c. 7th century CE) Middle Chinese mju, (c. 3rd century CE) Late Han Chinese muɑ, and reconstructed (c. 6th century BCE) Old Chinese *ma.
Other varieties of Chinese have differing pronunciations of 無. Compare Cantonese mou4 or mou; and Min Nan IPA: [ bo˧˥ ] (Quanzhou) and [ bə˧˥ ] (Zhangzhou).
The common Chinese word wu 無 was adopted in the Sino-Japanese, Sino-Korean, and Sino-Vietnamese vocabularies. The Japanese kanji 無 has on'yomi "Chinese readings" of mu or bu, and a kun'yomi "Japanese reading" of na. The Korean hanja 無 is read mu (in Revised, McCune–Reischauer, and Yale romanization systems). The Vietnamese Han Viet character 無 is pronounced vô or mô.
Some English translation equivalents of wu or mu 無 are:
"no", "not", "nothing", or "without"
nothing, not, nothingness, un-, is not, has not, not any
Nonexistence; nonbeing; not having; a lack of, without. A negative. Caused to be nonexistent. Impossible; lacking reason or cause. Pure human awareness, prior to experience or knowledge. This meaning is used especially by the Chan school. The 'original nonbeing' from which being is produced in the Daode jing.
In modern Chinese, Japanese and Korean it is commonly used in combination words as a prefix to indicate the absence of something, e.g., Chinese: 无线; pinyin: wúxiàn / musen (無線?) / museon (무선 ) for "wireless". In Classical Chinese, it is an impersonal existential verb meaning "not have".
The same character is also used in Classical Chinese as prohibitive particle, though in this case it is more properly written Chinese: 毋; pinyin: wú.
Old Chinese *ma 無 is cognate with the Proto-Tibeto-Burman *ma "not". This reconstructed root is widely represented in Tibeto-Burman languages, for instance, ma means "not" in both Written Tibetan and Written Burmese.
In traditional Chinese character classification, the uncommon class of phonetic loan characters involved borrowing the character for one word to write another nearly homophonous word. For instance, the character 其 originally depicted a ji "winnowing basket", and scribes used it as a graphic loan for qi 其 "he; she; it", which resulted in a new character ji 箕 (clarified with the bamboo radical ⺮) to specify the basket.
The character wu 無 originally meant "dance" and was later used as a graphic loan for wu "not". The earliest graphs for 無 pictured a person with outstretched arms holding something (possibly sleeves, tassels, ornaments) and represented the word wu "dance; dancer". After wu 無 "dance" was borrowed as a loan for wu "not; without", the original meaning was elucidated with the 舛 "opposite feet" at the bottom of wu 舞 "dance".
The text of the Mu-koan
The Gateless Gate, which is a 13th-century collection of Chan or Zen kōans, uses the word wu or mu in its title (Wumenguan or Mumonkan 無門關) and first kōan case ("Joshu's Dog" 趙州狗子). Chinese Chan calls the word mu 無 "the gate to enlightenment". 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"'.
Case 1 of The Gateless Gate reads as follows:
Chinese English translation
A monk asked Zhaozhou Congshen, a Chinese Zen master (known as Jōshū in Japanese), "Has a dog Buddha-nature or not?" Zhaozhou answered, "Wú" (in Japanese, Mu)
The koan originally comes from the Zhaozhou Zhenji Chanshi Yulu (Chinese: 趙州真際禪師語錄), The Recorded Sayings of Zen Master Joshu, koan 132:
Chinese English translation
A monk asked, "Does a dog have a Buddha-nature or not?"
The master said, "Not [Mu]!"
The monk said, "Above to all the Buddhas, below to the crawling bugs, all have Buddha-nature. Why is it that the dog has not?"
The master said, "Because he has the nature of karmic delusions".
The Book of Serenity Chinese: 從容録; pinyin: cóngrónglù, 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.
Chinese English translation
A monk asked Master Joshu, "Does a dog have Buddha Nature?"
Joshu replied, "Yes."
And then the monk said, "Since it has, how did it get into that bag of skin?"
Joshu said, "Because knowingly, he purposefully offends."
In the original text, the question is used as a conventional beginning to a question-and-answer exchange (mondo). The reference is to the Nirvana Sutra which says for example:
In this light, the undisclosed store of the Tathagata is proclaimed: "All beings have the Buddha-Nature".
Koan 363 in the Zhaozhou Zhenji Chanshi Yulu shares the same beginning question.
This koan is one of several traditionally used by Rinzai school to initiate students into Zen study, and interpretations of it vary widely.
Yasutani Haku'un of the Sanbo Kyodan maintained that
The koan is not about whether a dog does or does not have a Buddha-nature because everything is Buddha-nature, and either a positive or negative answer is absurd because there is no particular thing called Buddha-nature.
The Japanese scholar Iriya Yoshitaka 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. To the question "Does a dog have the Buddha-nature?", on the one hand Monk Chao-chou replied affirmatively, but on the other hand he replied negatively. However, Zen adherents in Japan have rendered the koan exclusively in terms of his negative response, and completely ignored the affirmative one. Moreover, it has been the custom from the outset to reject the affirmative response as superficial compared to the negative one. It seems that the Wu-men kuan is responsible for this peculiarity.
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. This approach takes the “Mu” response in a non-literal way to express a transcendental negation that becomes the topic of an intensive contemplative experience, during which any and all thoughts or uses of reason and words are to be cut off and discarded for good rather than investigated for their expressive nuances and ramifications. Yet, historical studies demonstrate quite persuasively that an overemphasis on this single approach to one version of the kōan is somewhat misleading.
"Unasking" the question
The term is often used or translated to mean that the question itself must be "unasked": no answer can exist in the terms provided. Zhaozhou's answer, which literally means that dogs do not have Buddha nature, has been interpreted by Robert Pirsig and Douglas Hofstadter to mean that such categorical thinking is a delusion, that yes and no are both correct and incorrect.
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". He offered the example of a computer circuit using the binary numeral system, in effect using mu to represent high impedance:
For example, it's stated over and over again that computer circuits exhibit only two states, a voltage for "one" and a voltage for "zero." That's silly! Any computer-electronics technician knows otherwise. Try to find a voltage representing one or zero when the power is off! The circuits are in a mu state.
The word features prominently with a similar meaning in Douglas Hofstadter's 1979 book, Gödel, Escher, Bach. It is used fancifully in discussions of symbolic logic, particularly Gödel's incompleteness theorems, to indicate a question whose "answer" is to
un-ask the question,
indicate the question is fundamentally flawed, or
reject the premise that a dualistic answer can or will be given.
"Mu" may be used similarly to "N/A" or "not applicable," a term often used to indicate the question cannot be answered because the conditions of the question do not match the reality. A layperson's example of this concept is often invoked by the loaded question "Have you stopped beating your wife?", to which "mu" would be the only respectable response.
Because of this meaning, programming language Perl 6 uses "Mu" for the root of its type hierarchy.