Soto and Rinzai Zen Masters on the Koan "Mu" (Tendo Nyojo & Mumon)

While the "Soto" and "Rinzai" Zen sects are asserted to differ on a variety of issues regarding the teachings of Zen practice and enlightenment, their differing view on the role of "Koans" is often the most emphatic.

In light of this, it is interesting to examine and compare the koan instructions given by two Zen masters that are both highly revered by their respective sects. For the "Soto" position, Master Eihei Dogen's teacher, Tendo Nyojo, is considered an excellent representitve. For the "Rinzai" position, Master Mumon, author of the Mumonkan, is considered to be one of the best koan representives in Zen history.

Fortunately, both of these masters are on record giving instruction on what is probably the most well known of all Zen koans, Case 1 of the Mumonkan. Look how these two Zen masters from opposite lineages approach Joshu's 'Mu.'

Jõshû's "Mu　趙州狗子

趙州和尚、因僧問、狗子還有佛性也無。州云、無。
A monk asked Jõshû, "Has a dog the Buddha Nature?" Jõshû answered, "Mu."

Now here is Mumon's instruction:

"In order to master Zen, you must pass the barrier of the patriarchs. To attain this subtle realization, you must completely cut off the way of thinking. If you do not pass the barrier, and do not cut off the way of thinking, then you will be like a ghost clinging to the bushes and weeds.

Now, I want to ask you, what is the barrier of the patriarchs? Why, it is this single word 'Mu.' That is the front gate to Zen. Therefore it is called the 'Mumonkan of Zen.' If you pass through it, you will not only see Jõshû face to face, but you will also go hand in hand with the successive patriarchs, entangling your eyebrows with theirs, seeing with the same eyes, hearing with the same ears. Isn't that a delightful prospect? Wouldn't you like to pass this barrier?

Arouse your entire body with its three hundred and sixty bones and joints and its eighty-four thousand pores of the skin; summon up a spirit of great doubt and concentrate on this word 'Mu.' Carry it continuously day and night. Do not form a nihilistic conception of vacancy, or a relative conception of 'has' or 'has not.' It will be just as if you swallow a red-hot iron ball, which you cannot spit out even if you try. All the illusory ideas and delusive thoughts accumulated up to the present will be exterminated, and when the time comes, internal and external will be spontaneously united. You will know this, but for yourself only, like a dumb man who has had a dream.

Then all of a sudden an explosive conversion will occur, and you will astonish the heavens and shake the earth. It will be as if you snatch away the great sword of the valiant general Kan'u and hold it in your hand. When you meet the Buddha, you kill him; when you meet the patriarchs, you kill them. On the brink of life and death, you command perfect freedom; among the sixfold worlds and four modes of existence, you enjoy a merry and playful samadhi.

Now, I want to ask you again, 'How will you carry it out?' Employ every ounce of your energy to work on this 'Mu.' If you hold on without interruption, behold: a single spark, and the holy candle is lit!'
~Trans. Katsuki Sekida

Here is Tendo Nyojo's instruction:

"When thoughts are flying around your mind in confusion, what do you do? 'A dog’s Buddha-nature? No (Mu).' This one word No (Mu) is an iron broom: Where you sweep there is a lot of flying around, and where there is a lot of flying around, you sweep. The more you sweep, the more there is. At this point where it is impossible to sweep, you throw your whole life into sweeping. Keep your spine straight day and night, and do not let your courage flag. All of a sudden you sweep away the totality of space, and all differentiations are clearly penetrated, so the source and its meanings become evident."
~ Trans. Thomas Cleary

Comparison:
Mumon: "...you must completely cut off the way of thinking...
Tendo Nyojo: "When thoughts are flying around your mind in confusion..."

Mumon: "'How will you carry it out?' Employ every ounce of your energy to work on this 'Mu.'"
Tendo Nyojo: "...what do you do? 'A dog's Buddha-nature? No (Mu)."

Mumon: "...what is the barrier of the patriarchs? Why, it is this single word 'Mu.'
Tendo Nyojo: "This one word No (Mu) is an iron broom..."

Mumon: "Arouse your entire body with its three hundred and sixty bones and joints and its eighty-four thousand pores of the skin; summon up a spirit of great doubt and concentrate on this word 'Mu.'"
Tendo Nyojo: "At this point where it is impossible to sweep, you throw your whole life into sweeping."

Mumon: "Carry it continuously day and night."
Tendo Nyojo: "Keep your spine straight day and night, and do not let your courage flag."

Mumon: "It will be just as if you swallow a red-hot iron ball, which you cannot spit out even if you try."
Tendo Nyojo: "The more you sweep, the more there is."

Mumon: "Then all of a sudden..."
Tendo Nyojo: "All of a sudden..."

Mumon: "All the illusory ideas and delusive thoughts accumulated up to the present will be exterminated... internal and external will be spontaneously united... an explosive conversion will occur..."
Tendo Nyojo: "...you sweep away the totality of space, and all differentiations are clearly penetrated..."

Mumon: "You will know this, but for yourself only..."
Tendo Nyojo: "...the source and its meanings become evident."

While there are some subtle differences here, the common characteristics seem to outweigh them for the most part. Having employed both of these methods to the best of my ability, I have not discerned any difference in the actual experience. If anyone else has, please share your comments.

Note: While both Tendo Nyojo and Mumon recommend taking up this koan in Zazen , I would not recommend doing so without a reliable teacher. Unfortunately, many Soto 'teachers' flatly deny that 'Soto' Zen masters (often they mean 'Dogen') ever recommended taking up koans in Zazen, hence few Soto 'teachers' have developed the capacity to instruct students in koan-introspection (this is not to say that no Soto teachers have undergone this training, but very few have).

Dogen's records are full of many references to the Mu koan, and I highly recommend his writings to see how he uses it in some intriguing ways.

Gassho,
Ted Biringer
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