The Book of Mu - Selections

Essential Writings on Zen’s Most Important Koan


352 pages, 6 x 9 inches


ISBN 9780861716432

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The Koan Mu: Text, Commentary, and Verse
by Wumen Huikai, translated by Robert Aitken

The Case

A monk asked Chao-chou, “Has the dog buddha nature or not?”
Chao-chou said, “Mu.”

Wu-men’s Comment

For the practice of Zen it is imperative that you pass through the barrier set up by the Ancestral Teachers. For subtle realization it is of the utmost importance that you cut off the mind road. If you do not pass the barrier of the ancestors, if you do not cut off the mind road, then you are a ghost clinging to bushes and grasses.

What is the barrier of the Ancestral Teachers? It is just this one word “Mu”—the one barrier of our faith. We call it the Gateless Barrier of the Zen tradition. When you pass through this barrier, you will not only interview Chao-chou intimately. You will walk hand in hand with all the Ancestral Teachers in the successive generations of our lineage—the hair of your eyebrows entangled with theirs, seeing with the same eyes, hearing with the same ears. Won’t that be fulfilling? Is there anyone who would not want to pass this barrier?

So, then, make your whole body a mass of doubt, and with your three hundred and sixty bones and joints and your eighty-four thousand hair follicles concentrate on this one word “Mu.” Day and night, keep digging into it. Don’t consider it to be nothingness. Don’t think in terms of “has” and “has not.” It is like swallowing a red-hot iron ball. You try to vomit it out, but you can’t.

Gradually you purify yourself, eliminating mistaken knowledge and attitudes you have held from the past. Inside and outside become one. You’re like a mute person who has had a dream—you know it for yourself alone.

Suddenly Mu breaks open. The heavens are astonished, the earth is shaken. It is as though you have snatched the great sword of General Kuan. When you meet the Buddha, you kill the Buddha. When you meet Bodhidharma, you kill Bodhidharma. At the very cliff edge of birth-and-death, you find the Great Freedom. In the Six Worlds and the Four Modes of Birth, you enjoy a samadhi of frolic and play.

How, then, should you work with it? Exhaust all your life energy on this one word “Mu.” If you do not falter, then it’s done! A single spark lights your Dharma candle.

Wu-men’s Verse

Dog, buddha nature—
the full presentation of the whole;
with a bit of “has” or “has not”
body is lost, life is lost.

Three Commentaries
by Dahui Zonggao, translated by J.C.Cleary

1. To Ch’en Li-jen Contemplating “No”

A monk asked Chao-chou, “Does a dog have buddha nature or not?” Chao-chou said, “No.” This one word “no” is a knife to sunder the doubting mind of birth and death. The handle of this knife is in one’s own hand alone: you can’t have anyone else wield it for you: to succeed you must take hold of it yourself. You consent to take hold of it yourself only if you can abandon your life. If you cannot abandon your life, just keep to where your doubt remains unbroken for a while: suddenly you’ll consent to abandon your life, and then you’ll be done. Only then will you believe that when quiet it’s the same as when noisy, when noisy it’s the same as when quiet, when speaking it’s the same as when silent, and when silent it’s the same as when speaking. You won’t have to ask anyone else, and naturally you won’t accept the confusing talk of false teachers.

During your daily activities twenty-four hours a day, you shouldn’t hold to birth and death and the Buddha Path as existent, nor should you deny them as nonexistent. Just contemplate this: A monk asked Chaochou, “Does a dog have buddha nature or not?” Chao-chou said, “No.”

2. To Chang An-kuo Contemplating a Saying

Before emotional consciousness has been smashed, the mind-fire burns bright. At just such a time, just take a saying you have doubts about to arouse and awaken yourself. For example: A monk asked Chao-chou, “Does a dog have buddha nature or not?” Chao-chou said, “No.” Just bring this up to arouse and awaken yourself. Whatever side you come at it from, that’s not it, you’re wrong. Moreover, don’t use mind to await enlightenment. And you shouldn’t take up the saying in the citation of it. And you shouldn’t understand it as the original subtlety, or discuss it as existent or nonexistent, or assess it as the nothingness of true nothingness. And you shouldn’t sit in the bag of unconcern. And you shouldn’t understand it in sparks struck from stone or in the brilliance of a lightning flash. There should be no place to employ your mind.When there’s no place for mind, don’t be afraid of falling into emptiness—on the contrary, this is a good place. Suddenly the rat enters a hollow ox horn, [that is, discriminating consciousness reaches an impasse] and then wrong views are cut off.

This affair is neither difficult nor easy. Only if you have already planted deep the seeds of transcendent wisdom, and served men of knowledge through vast eons without beginning, and developed correct knowledge and correct views, does it strike you continuously in your present conduct as you meet situations and encounter circumstances in the midst of radiant spiritual consciousness, like recognizing your own parents in a crowd of people. At such a time, you don’t have to ask anyone else: naturally the seeking mind does not scatter and run off.

Yun-men said, “When you can’t speak, it’s there; when you don’t speak, it’s not there. When you can’t discuss it, it’s there; when you don’t discuss it, it’s not there.” He also commented saying, “You tell me, what is it when you’re not discussing it?” Fearing people wouldn’t understand, he also said, “What else is it?”

3. To Tsung Chih-ko Contemplating “No”

You inform me that as you respond to circumstances in your daily involvement with differentiated objects, you’re never not in the Buddhadharma. You also say that amidst your daily activities and conduct you use the saying “A dog has no buddha nature” to clear away emotional defilements. If you make efforts like this, I’m afraid you’ll never attain enlightened entry. Please examine what’s under your feet: where do differentiated objects arise from? How can you smash emotional defilements in the midst of your activities with the saying “A dog has no buddha nature”? Who is it who can know he’s clearing away emotional defilements?

Didn’t Buddha say: “Sentient beings are inverted: they lose themselves and pursue things.” Basically things have no inherent nature: those who lose themselves pursue them on their own. Originally objects are undifferentiated: those who lose themselves do their own differentiating. (You say) you have daily contact with differentiated objects, and you’re also within the Buddhadharma. If you’re in the Buddhadharma, it’s not an object of differentiation; if you’re among differentiated objects, then it’s not the Buddhadharma. Pick one up, let one go—what end will there be?

At the Nirvana Assembly [when the Nirvana Sutra was expounded, just before the Buddha’s death], the broad-browed butcher put down his slaughtering knife and immediately attained buddhahood where he stood. How could you have so much sadness and sorrow? In your daily activities as you respond to circumstances, as soon as you become aware of being involved with differentiated objects, just go to the differentiating to raise the saying “A dog has no buddha nature.” Don’t think of it as clearing away, and don’t think of it as emotional defilement; don’t think of it as differentiation, and don’t think of it as the Buddhadharma— simply contemplate the saying “A dog has no buddha nature.” Just bring up the word “No.” And don’t set your mind on it and await enlightenment. If you do, objects and the Buddhadharma are differentiated, emotional defilements and the saying “A dog has no buddha nature” are differentiated, interrupted and uninterrupted are differentiated, and encountering the confusion of emotional defilements so body and mind are unsettled and being able to know so many differentiations are also differentiated.

If you want to remove this disease, just contemplate the word “No.” Just look at the broad-browed butcher putting down his knife and saying, “I am one of the thousand buddhas.” True or false? If you assess it as false or true, again you plunge into objects of differentiation. It’s not as good as cutting it in two with a single stroke. Don’t think of before and after: if you think of before and after, this is more differentiating.

Hsuan-sha said this matter “Cannot be limited—the road of thought is cut off. It does not depend on an array of adornments—from the beginning it’s been real and pure. Moving, acting, talking, laughing, clearly understanding wherever you are, there’s nothing more lacking. People these days do not understand the truth in this, and vainly involve themselves with sensory phenomena, getting defiled all over and tied down everywhere. Even if they understand, sense objects are present in complex confusion, names and forms are not genuine, so they try to freeze their minds and gather in their attention, taking things and returning them to emptiness, shutting their eyes, hiding their eyes; if a thought starts up, they immediately demolish it; as soon as the slightest conception arises, they immediately press it down. Those with a view like this are outsiders who have fallen into empty annihilation, dead men whose spirits have not yet departed, dark and silent, without awareness or knowledge. They’re “covering their ears to steal the bell,” vainly deluding themselves.

All you said in your letter was the disease Hsuan-sha condemned— the perverted Ch’an of quiescent illumination, a pit to bury people in. You must realize this. When you bring up a saying, don’t use so many maneuvers at all—just don’t let there be any interruption whether you’re walking, standing, sitting, or lying down. Don’t discriminate joy and anger, sorrow and bliss. Just keep on bringing up the saying, raising it and raising it, looking and looking. When you feel there’s no road for reason and no flavor, and in your mind you’re oppressed and troubled, this is the place for each person to abandon his body and his life. Remember, don’t shrink back in your mind when you see a realm like this—such a realm is precisely the scene for becoming a buddha and being an ancestral teacher.

And yet the false teachers of silent illumination just consider wordlessness as the ultimate principle, calling it the matter of “the Other Side of the Primordial Buddha,” or of “before the Empty Eon.” They don’t believe there is a gate of enlightenment, and consider enlightenment as a lie, as something secondary, as an expedient word, as an expression to draw people in. This crowd deceive others and deceive themselves, lead others into error and go wrong themselves. You should also realize this.

In the conduct of your daily activities, as you’re involved with differentiated objects, when you become aware of saving power, this is where you gain power. If you use the slightest power to uphold it, this is definitely a false method—it’s not Buddhism. Just take the mind, so longlasting, and bring it together with the saying “A dog has no buddha nature.” Keep them together till the mind has no place to go—suddenly, it’s like awakening from a dream, like a lotus flower opening, like parting the clouds and seeing the moon. When you reach such a moment, naturally you attain unity. Through the upsets and errors of your daily activities, just contemplate the word “No.” Don’t be concerned with awakening or not awakening, getting through or not getting through. All the buddhas of the three worlds were just unconcerned people, people for whom there is nothing; all the generations of ancestral teachers too were just people without concerns. An ancient worthy said, “just comprehend nothingness in the midst of things, unconcern amidst concerns: when seeing forms and hearing sounds, don’t act blind and deaf.” Another ancient worthy said, “Fools remove objects but don’t obliterate mind; the wise wipe out mind without removing objects.” Since in all places there’s no mind, all kinds of objects of differentiation are nonexistent of themselves.

Gentlemen of affairs these days, though, are quick to want to understand Ch’an. They think a lot about the scriptural teachings and the sayings of the ancestral teachers, wanting to be able to explain clearly. They are far from knowing that this clarity is nonetheless an unclear matter. If you can penetrate the word “No,” you won’t have to ask anyone else about clear and unclear. I teach gentlemen of affairs to let go and make themselves dull—this is this same principle. And it’s not bad to get first prize in looking dull, either—I’m just afraid you’ll hand in an empty paper. What a laugh!


How to cite this document:
© James Ishmael Ford and Melissa Myozen Blacker, The Book of Mu (Wisdom Publications, 2011)

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