In his Western classic on Zen, The Three Pillars of Zen, Philip Kapleau wrote:

Ever since Chao-Chou (Joshu), one of the great Chinese Zen masters of the T’ang era, retorted “Mu!” to a monk who had asked whether dogs have the Buddha-nature, the reverberations of the incident have been echoing through the halls of Zen monasteries and temples down through the centuries.  Even in this day no koan is assigned novices more often.  It is commonly agreed among Japanese masters that it is unsurpassed for breaking asunder the mind of ignorance and opening the eye of Truth.

In the Mumonkan (The Gateless Barrier), compiled by Zen master Wu-Hen (Mumon), Mu heads the collection of forty-eight koans.  What is the source of Mu’s power, what has enabled it to hold first rank among koans for over a thousand years?

…...Master Mumon worked zealously on it for six years and finally came to Self-realization.  Evidently it made a deep impression on him, for he placed it first in the collection of his forty-eight koans.

…..”Has a dog Buddha-nature or not?” raised the question :  What is Buddha-nature?  A well known passage in the Nirvana sutra states that every sentient being has Buddha-nature.

In actual fact, the original monk was in an intellectual dilemma about the authority of Mahayana Buddhist scriptures.  The Nirvana Sutra says all ‘sentient beings’ (including animals, as for example, dogs) have Buddha-nature (which is Self-awareness which gets reflected in the mirror of the reincarnating causal body as dualistic timespace “I” or ego, which creates in the causal body a faculty called ahamkara, ego-maker in Sanskrit.)  But another Mahayana Buddhist scripture read by the monk says that only human beings have Buddha-nature.  Therefore, Buddha seems to have heavily contradicted Himself on this important issue!  So, the monk did not know what to believe.  He was having in fact a deeply disturbing crisis-of-faith in Buddhism itself, which was therefore also a crisis-of-faith in T’san/Zen itself as The Path To Self-realization or Supreme Enlightenment.  So naturally he asked the Big Burning Question to his master, Joshu, to put an end to his doubts so that he might put his mind at rest and continue in his forward progress as he understood it in those days.  The master, Joshu, gave the correct answer intuitively, but not with complete knowledge, I am sorry to have to say.  So the answer of Joshu/Chao-Chou, was not a fully Enlightened answer and has therefore remained a bad, inadequate koan to this day.  The statement “Wu”/”Mu” (“No”) also did not “enlighten” the perplexed monk, nor did Mumon himself become truly “Enlightened” after six years of reproducing the original monk’s dilemma in his own mind, unless he had learned to cut through the whole farce, which his commentary shows he failed to do.  So, the horrible fact remains that of all the potentially enlightening koans in Mumons’s collection, the Mu Koan is the worst and least suitable.

If you want to understand how extensive the farce has run through Japan right down to today, including how utterly ignorant the majority of so-called “Zen Masters” have been and remain in Japan, read the Theosophical book, The Causal Body by A.E. Powell, which explains quite ably how Group Animal Causal Bodies form a potential Human Causal Reincarnating Individual (Jeevatma).  Of course Buddhism never got this knowledge down and we have to turn to Occult Hinduism and Esoteric Buddhism (Theosophy) to get the real solution to the Mu Koan, though even real esoteric knowledge about the process of individualization of evolved and ready animal group causal spheres will not necessarily cause anyone to suddenly become Enlightened, though such knowledge is a wonderful meditation theme that can give one good insights into how animal, human and superhuman evolution work, which can already put one light-years ahead of dogmatic and prejudiced Japanese Mahayana Buddhists and pseudo-enlightened so-called “Zen Masters”.

There is an advanced cognitive process to be found in T’san/Zen which includes the accelerated learning and enlightening method of looking into stories of exchanges between Masters and Disciples of T’san/Zen in Ancient China, just as Sufi novices can learn a great deal from studying Sufi teaching stories brought out by Idries Shah.  Whether “teaching stories” in one tradition or “Kun-Ans”/”Koans”/”Case-records” in another tradition, the learning method is basically the same.  However, Zen explanations of it by their “masters” and Sufi explanations of it by their “masters” often show widely differing perspectives, though neither is complete in itself as it pretends to be.  However, a great deal of personal benefit is to be had by parallel study and meditation in both traditions, for both have irreplaceable insights for seriously seeking consciousness toward superconsciousness once consciousness itself has been transformed and stilled as in Rajayoga Samadhi.

I have not put this treatment of the Koan of Mu with my other Koan Articles because of the inadequate and absurd history of the koan itself.  New insight and development have to take place now about what one can get from either a Zen Koan or a Sufi Teaching Story.  Otherwise, all sorts of seekers and novices will continue to labor under false authorities and their presumptions, whether they are of the West or some Eastern dogmatic and petty tradition.  Let us also not forget that it is not really Gautama Buddha speaking in Mahayana scriptures, but Nagarjuna (which means, “Friend-of-the-Aliens” as naga in Sanskrit means “alien extraterrestrial being”).  You see, Nagarjuna was extremely disappointed in what he considered to be the wholly incomplete and inadequate teachings of the historical Buddha.  Through divine and cosmic mercy for both himself and humanity in general, he was given extensive Alien Extraterrestrial Intelligence Contact.  He was taken to another planet (ostensibly “under the ocean”) and educated where he was taught a form of AUI or Cosmic Language and given access to an immense Alien library of evolutionary and spiritual subjects.  Returning to Earth he wrote more advanced Extraterrestrial spiritual perspectives under the guise of finding “Lost and Found” unknown teachings of Gautama Buddha.

In essence, T’san/Zen originates on another planet through forming its actual metaphysical background as developed, for instance, in the incredibly significant Hwa Yen Sutra, which any student of Zen should deeply study in this new cosmic light.  Add Hwa Yen to Bodhidharma staring at a cave-wall to force recognition of Direct Experience Beyond Mahayana Scriptures.  Then add Theosophy as the next step of Esoteric Mahayana.  Then add Jiddu Krishnamurti as the next example of Direct Experiencing Beyond Spiritual Authorities and Scriptures On Earth.  With this new global, cosmic and unprejudiced universal perspective, your Buddhi or Higher Causal Intellect can blossom into a Dharmakaya with a shot at having a Turiya Samadhi of Atman or Self-nature (The Godself or White Divine Star) as a Vajrakaya, Diamond Body of Greater Buddhahood!

The Dharmakaya Enlightenment is the lesser Enlightenment whereas the Vajrayana Enlightenment is the Greater Enlightenment.  This is the Divine Truth and Reality of all this!

The overwhelming majority of Zen Buddhists in Japan, Korea and China cannot handle the real truth of the Extraterrestrial and Cosmic roots of Mahayana Buddhism through Nagarjuna.  Dogmatic, conditioned and fixed cognitive patterns in their organic, physical brains cannot have the necessary paradigm shift due to weakness and inertness in their causal essence.  They are hopelessly stuck in Guest Position, just as most so-called “Sufi Masters” in the Middle-East are also stuck in their cognitive patterns of conditioned belief.

What really happened to Nagarjuna is important for the evolutionary future of Search-For-Truth on Earth.  Did you know that Little Grey Aliens would disguise themselves as children on Earth in order to attend Nagajuna’s lectures on Earth without getting Earth-humans upset?  It is a recorded and documented historical fact that the “Nagas” would attend his lectures in that manner.

In Tibetan Vajrayana Buddhism, Nagas are called Dakas (male) or Dakinis (female).  AUI or Cosmic Language is called “The Language of the Dakinis”.  When Buddhist Siddhas or highly developed people were allowed to depart humanity and go on Alien Spacecraft to dwell on other more advanced and congenial planets, the Tibetans would say, “They went to the Land of the Dakinis”.  Thus truly Enlightened and Developed human beings do not necessarily have to stay and die as prisoners of the Prison Planet Earth.  Enlightenment can include Physical Liberation from humanity and its abusive stupidities and false spiritual authorities.

There is a Cosmic Zen!  In fact, it is the only kind really worth anything.  As for the mere local varieties, they tend to be just a pile of shit soaking into the ground.