Contrary to Western belief, Zen can neither be practiced nor understood without some knowledge of the concept of Buddhahood and the principles of meditation. Each requires a book to do it justice. Nevertheless, the following brief account of the three aspects of Buddhahood, the six patterns of human thought, the seven different types of meditation practice, and the three successive stages of meditation will be useful to the beginner.
The Three Aspects of Buddhahood in Relation to the Six Patterns of Human Thinking
What is "Buddha"? To this question there have been many answers. Some religionists say that He founded a form of heathenism called "Buddhism"; the man in the street says that He is an idol worshipped by misguided Orientals; some philosophers say that He was a thinker who taught and established the philosophy and religion called "Buddhism"; historians say that "The Buddha" is a reverential title attributed to a person called Gautama Sakyamuni, who lived some time between 560 and 480 B.C. – and so on.
But how do the devotees of Buddhism themselves envision Buddha from their religious point of view, and how do they define Him as representing a supreme goal – one to be adored, imitated, and achieved? This question is of the utmost importance, because it penetrates directly to the very heart of Buddhism itself, and is akin to the inquiry into the nature of God which has always been regarded as the central theme in the study of most religions. There is a Tibetan proverb which says: "If one understands the meaning of the term 'Buddha,' one knows all of Buddhism." From the viewpoint of an outsider, this statement may seem to be an exaggeration; but the orthodox Buddhist holds it to be very close to the truth. In the past twenty-five centimes many Buddhist scholars have spent their whole lives studying this question, and have written endless and complicated commentaries on it which only add to the confusion. Fortunately, the subject can be simplified by the following definition which is accepted by most Buddhist devotees: A Buddha is one who possesses Perfect Wisdom, Perfect Compassion, and Perfect Power. Let us consider, one by one, these three essentials of Buddhahood.
The Perfect Wisdom of Buddha
The Perfect Wisdom of Buddha has two facets, one called "The Wisdom of Knowing the Thing as It Is" (Chinese: Ju so yu chih), and the other called "The Wisdom of Knowing All" (Chinese: Chin so yu chih). The former may be understood as "Vertical" and the latter as "Horizontal Wisdom."
Imagine the water in a cup. The ordinary person will see it as nothing but a cup of plain water, that is, a liquid with which to quench his thirst; a chemist, as a compound of hydrogen and oxygen; a physicist, as the complex result of electronic movement; a philosopher, as something expressing "relationships" and "causation"; an enlightened Bodhisattva, as the manifestation of his own mind; and Buddha, as the outflow of perfect Buddhahood. Converging within this simple object – a cup of water – are a great many realms of existence and depths of Being for our intelligence to reach, measure, and comprehend. The shallowness or depth of our intelligence determines the realms to which it is capable of penetrating. The "Vertical Wisdom" of Buddha, therefore, is a penetrating insight – successively piercing through all the different levels and realms of existence to touch the very depths of Being itself. It is a wisdom of profundity, a wisdom that goes beyond the realms of common sense, science, philosophy, and religion; a wisdom that probes into the uttermost depths of Dharma – the indescribable and unthinkable "Suchness." This is "Vertical Wisdom."
On the other hand, the meaning of "Horizontal Wisdom," or "The Wisdom-of-Knowing-AU," is clearly indicated by the term itself. It denotes the omniscient aspect of Buddha's Wisdom, which is capable of knowing everything and is therefore rather difficult for modem people to accept. The famous Chinese philosopher, Chuang Tzu,  said: "Life is finite while knowledge is infinite. To pursue infinite knowledge in this finite life is indeed hopeless!" Men of the twentieth century feel especially sympathetic toward statements such as this.
In the old days there were undoubtedly certain great scholars or sages who were regarded by their contemporaries as wise men who "knew everything." A Chinese proverb says: "A Confucian scholar is put to shame if there is one branch of learning that he does not know." But nowadays we think it presumptuous for a man to claim to know everything, even in one field of learning. Therefore, to many people it seems that All-knowing Wisdom is something supernatural and beyond the reach of the human mind.
Contrary to this common belief, however, Buddhism asserts that every sentient being is a potential Buddha, capable of reaching Buddhahood (which includes this All-knowing Wisdom) if he makes a correct and sufficient effort. If this be so, how then does Buddhism convincingly explain such a possibility as "knowing all" to us? To answer this question we must first analyze the patterns, or molds, within which the human mind functions.
As a result of such analysis, Mahayana scholars have concluded that the human mind functions in accordance with six basic patterns, or ways of thinking, that is, cumulatively, limitatively, discordantly, delusively, impotently and wastefully, and "clingingly." Influenced by these faulty and deep-rooted habitual ways of thought, we find it natural to believe that "Omniscient Wisdom" is something very attractive to contemplate, but completely beyond our grasp.
But suppose we could transform these faulty patterns within which our minds have so far functioned into new forms, elevating the mind to new horizons and freeing it from all its former "attachments," would the Wisdom-of-Knowing-All still appear to be as remote and unattainable as before? The vision of the human eye is limited, but with the assistance of instruments its scope can be extended to hitherto inaccessible regions of space.
Would not a simile such as this be applicable to the problem of the limited human mind versus the Wisdom of Omniscience? Before attempting to answer this question, we must first examine the six basic patterns of human thought mentioned above, and see in what manner they have molded the functions of the human mind.
The Six Patterns of Human Thinking
1. The human way of thinking is cumulative. This means that human knowledge is gained through a "building-up" process, a process of gradual accumulation. For example, when we were children in school, we were first taught the alphabet; then we were taught to read words and sentences and later to write letters, "themes," or compositions. Finally, the knowledge accumulated and the talent developed may have enabled us to write books, or to express creatively highly complicated thoughts and new ideas. This process through which human knowledge is gained is one of building and adding to, of welding newly acquired segments of knowledge to the old mass. All is linked together by a process which is finite, partial, limitative, and conditional in its nature and origin. Because the very nature of this cumulative process has preconditioned and predetermined its outcome, it can never come to an end. There is no terminal point on the road of accumulation – we shall always find plenty of room in which to add something more. To collect drops of rain water from the roof of a house, even for a lifetime, will add nothing to the level of the ocean. Likewise, through a cumulative way of thinking, one will never be able to attain the All-knowing Wisdom of Buddhahood.
2. The human way of thinking is limitative. This is obvious since we all know that the human mind can usually think of only one thing at a time. We rarely find a gifted person who can give his attention to several things simultaneously, or deal with several problems at the same time. I remember that as a boy, when I was living in Peiping, I often loitered away my free time in the market place. My favorite spot was a certain "general store," the owner of which was a remarkable man. He could fix his mind on a number of different things simultaneously. He often sat on a high chair back of the counter, with a Chinese brush-pen in his right hand, writing up his accounts. Meanwhile the five fingers of his left hand were constantly moving up and down at great speed on an abacus; and at the same time his mouth never stopped talking to a customer or instructing his boy helper. Besides all this, his two big black eyes never slackened their watchfulness, lest a customer surreptitiously pick up something from a remote shelf. This man might be regarded as quite an unusual person. Nevertheless, the genius of his mind was still basically limitative, for even he could not think of as many as ten, let alone a hundred, a thousand, or an infinite number of things at the same time. Since the human mind almost invariably follows the "one-at-a-time" pattern to carry out its functionings, it has no choice but to remain in the region of finiteness and limitation.
3. The human way of thinking is discordant. Emotion and reason are two paramount, yet conflicting, elements that constitute the major portion of the ever fluctuating human mind. Emotion fills us with strong feelings of what we would like to do, but reason warns us coldly of what we should not do. Driven by these two conflicting forces, life is mainly a constant battle between the cold forces of reason and the hot forces of the emotions. In examining these two opponents, we find that they are not only opposite to, and offsetting each other, like water and fire, but also discover the interesting fact that they do not arise simultaneously. When reason has reached its highest peak, emotion is at its lowest ebb, and vice versa. For example, at a time when our minds are absorbed in trying to solve an abstruse problem in philosophy or mathematics, the reasoning faculties are in high gear, but the emotions are scarcely perceptible. On the other hand, at a time when we are in the throes of love-making, or furiously fighting an enemy, the emotions rise proportionately and reason drops to its lowest point. For this reason, we never hear of a mathematician or scientist formulating a new hypothesis or producing a new discovery when quarreling or making love. In the human mind reason and emotion are hostile forces offsetting, but not coexisting with, each other.
If this were also true in the Mind of Buddha, the consequences would indeed be catastrophic. Imagine that you are facing a vital problem, and have no other resort but to send an urgent and desperate prayer to Buddha. But he responds, "Wait, wait, my friend! Do not pray to me now; this is not the proper time, because my reason is very active at present but my emotions are low – I am not in the mood to grant favors. Try again tomorrow, when I may be in a better frame of mind!" This may sound ridiculous; but it actually illustrates a deep and significant truth of Buddhahood. A perfect Buddha must first have brought his reason and emotion together into complete and unalterable harmony before he could ever have reached Buddhahood. Emotion and reason, now transformed into Compassion and Wisdom, should arise simultaneously at all times without imbalance or fluctuation, and should merge together into one great, inseparable whole. The simultaneous arising of Compassion and Wisdom is indeed one of the great wonders of Buddhahood – a fascinating and vital topic much discussed by Mahayana Buddhist scholars everywhere.
4. The human way of thinking is delusive. Suppose we are now looking at the wall in our room; our eyes tell us that it is an upright, smooth surface standing stably and silendy before us. We walk one step forward to touch it, and find that the wall is something firm, cold, and solid. Then we remember what chemistry and physics have to say about a wall. They assert that it is composed of various compounds and elements containing innumerable atoms, electrons, protons, etc., all constantly moving at incredible speeds in their innumerable orbits. So our senses and our minds tell us radically different stories about the same thing. To which should we listen? We human beings are perpetually bombarded by discordant information conveyed by our different "sense-agents"; but fortunately we have a good "compromiser" or "arbitrator" – the mind – which synthesizes, integrates, and smooths out the conflicts between its agents, who are constandy reporting to "headquarters" from their various outposts.
Although our conscious mind is a remarkable agent in itself – practical, intelligent, and imaginative, its main concern in our everyday lives is not to check on whether the senses have conveyed the most reliable information, nor to give a verdict on their discordant findings, but rather to see that these agents work harmoniously together.
But here a serious question arises: Is the pragmatic approach taken by the human mind necessarily sound, and does not this integrating and "compromising" process result, perhaps, in a mutilation of the truth? If "right is right" and "wrong is wrong," as our reason tells us, and "right" cannot possibly be "wrong" at the same time, whose findings should we accept – the "static wall" of the eyes or the "dynamic wall" of the mind? From the viewpoint of the eyes, the static wall is right, from that of the mind, the dynamic wall, but from that of the nose, both are wrong. It is impossible to define right and wrong without an absolute standard. Fundamentally they are meaningful only when a certain standard or criterion has been established. Without such a standard, right and wrong both become meaningless. An absolute and final standard has thus been sought by philosophers and thinkers throughout all ages. Some argue that it is reason; others, that only God, or his Will, can be regarded as absolute, and so on. The final settlement of this problem seems well-nigh impossible. The search and the arguments go on ad infinitum.
While no final conclusion can be drawn, the Hua Yen  philosophy of Mahayana Buddhism suggests to us one solution. It holds that if any standard is by nature exclusive and "fixed," it can never be considered as "absolute" or final, for if absolute, it must be "all-inclusive" – a standard of totality – and so not an ordinary standard arbitrarily established to measure one thing against another. Such a standard cannot be otherwise than arbitrary and "deadly fixed"; its very nature sets it apart from the dynamic totality of Dharmadhatu. [Endnote 4-1]
The absolute standard should include, permeate, and embrace all. It is not a standard as such, but is, rather, a realm of wonder, a state of the perfect interpenetration of all Dharmas – the indescribable and inexplicable marvel of Buddhahood.
We seem to have an instinctive urge to seek the Truth, but somehow lack the capacity to find it. The dilemma of trying to set up an absolute standard is merely one of the many puzzles that have harassed mankind since the dawn of civilization. Man's search for Truth has been a never-ending obsession. Buddhist thinkers attribute this predicament to the delusive way of human thinking which, they say, if not qualitatively transformed, will drag man down forever into the morass of futile pursuit.
Another gulf that the human mind cannot bridge separates the realms of "indirect understanding" and "direct realization." We can understand the atomic structure of a thing, but we cannot see or experience it directly. Our minds can only give us the indirect measure of a thing; they cannot put us in direct contact with it. We can appreciate the grand idea of "all in one, and one in all"; but what we actually see around us is still the "all in all, and one in one." With hard work and deep thinking wc may come to understand the profound truth of Sunyata – the void nature of being as taught by the Prajnaparamita;  but all that we see and experience in our daily lives is within the Sangsaric realm of existence and subsistence. All these predicaments are caused by what Buddhists call "the delusive way of human thinking."
5. The human way of thinking is impotent and wasteful. According to the Buddhist sages, the major portion of our mental power or talent has never been fully utilized, and thus lies idle and dormant, in the deep recesses of our consciousness; even the small portion of power that is tapped by the average human mind is often diffused and squandered. If one can learn to concentrate, and thus more fully utilize his mental powers, his ability and perspective will be vastly enhanced. A great mind is not stolid or dull, nor is it feeble or capricious. Leaders are always keener minded and more stable than the average person. Their magnetism is also greater. Leadership is characteristic of a form of "natural concentration" which the common man lacks. The qualities that go to make a man more efficient and successful are the result of inborn or acquired powers of concentration, by means of which a man focuses all his mental forces and aims them directly at the problem in hand.
But, according to experienced Buddhist yogis, even if one can concentrate and control his mind reasonably well, he is still far from being able to utilize the major portion of the potential power that lies dormant in his Alaya, or "Store Consciousness." This "Store Consciousness" is a vast repository of power, talent, and knowledge that has accumulated throughout countess lives in the past. Being ignorant and incapable of utilizing this potential power of the Store Consciousness, the average man wastes his life away in trivial pursuits and futile endeavors, while the inexhaustible treasury available to him remains untapped. Buddhist sages therefore have stated that the human way of thinking is impotent and wasteful.
6. The human way of thinking is a "clinging" way of thinking. This sixth point, the most important point of all, delineates the innate tendency of the human mind to cling to the apparently "existent" or "substantial" aspect of things; it also implies that human thoughts are always of a "rigid" or "fixed" nature. The human mind seldom or never recognizes the void, insubstantial, and "indefinite" aspect of things. "Clinging" here means the tight grasping of the "existent" facet of all objects, which are then regarded as real and definitive – as if they were in possession of their own self natures.
In short, human clinging is by nature arbitrary, definitive, and exclusive – and so is diametrically opposed to the Buddhist teaching of Voidness and the Whole. All human thoughts are derived from or produced by the fundamental idea of "is-ness," which is essentially arbitrary, stubborn, and fixed. If we pierce into the very core of this idea of "is-ness," we sense it as being nothing but a deep rooted, colossal "clinging."
The study of human "clinging" is a vital subject in Buddhism; its great influence is reflected in Buddhist religion, philosophy, psychology, literature, and art – in practically all fields of Buddhist thought. The emphasis on the study of this crucial and significant subject is one of the outstanding features that have distinguished the teaching of Buddhism from that of other religions and philosophies. The reader is therefore advised to study this subject from whatever sources are available to him.
The above examination of the six patterns of human thought show incontrovertibly that if the All-knowing Wisdom of Buddhahood is attainable at all, it can never be reached through any of these six faulty paths. The innumerable Buddhist teachings are all aimed at correcting such faulty patterns in order to achieve Buddhahood. Among these teachings Dhyana (meditation) and Prajna (intuitive wisdom) are crucial. Through them the human consciousness can be transformed, and perfect Buddhahood achieved. Since Prajna is, on the one hand, the essence of Zen Buddhism, which has been briefly touched upon in the preceding chapters, and, on the other, a vast and comprehensive subject that must be studied exhaustively and independently if it is to be properly understood, this chapter will be confined to the survey of the different aspects of meditation practice in their relation to Buddhahood.
The Perfect Compassion of Buddha
The Perfect Compassion of Buddha is all-embracing and non-discriminative. It is an absolute and unconditioned Love. Like everything else in this world, love has a great many depths and grades of profundity. The greater love is, the less it binds itself to "conditions." Religious love is greater in scope and profounder in depth than personal or family love, or love for one's country, etc., because the latter forms are conditioned, and so are confined within the narrow boundary of human limitations.
However, there remains another boundary which even religious love seems unable to cross. For example, religion teaches us to love both our neighbors and our enemies, but seldom does it teach us to love "pagans." It admonishes us to love God, but forbids us to love "devils." Heresy has always been considered to be among the worst of crimes. "Thou shalt not worship false gods" is the paramount commandment in many religions. The spirit and love of a religion can easily transcend the boundaries of family and race, of life and death, but rarely can it transcend that of its own nature. This limitation is implicit in the very tenets of the religion itself. The fervent claim of many religionists that the love of their god is nondiscriminative and unconditioned is true only when their god alone is worshiped, their exclusive dogmas accepted, and their own creed adhered to.
The doctrine of exclusiveness that has caused so many misfortunes and confusions seems to have been impregnated in the very core of the religious intolerance reflected in the basic tenets of so many faiths. If we study these tenets in the light of the Prajnaparamita, we shall soon discover that behind all the pledged love and grace exalted in so many of the scriptures, there is a deep rooted clinging – a clinging to the "one true God," the "one true religion," the "one true principle," etc. – that characterizes and predestines their narrow limitations.
According to Buddhism, ultimate and unconditioned Love can only be achieved through a thorough realization of Voidness (Sunyata). The highest Compassion is attained only when the highest Wisdom is attained. In other words, the ultimate Compassion of Buddhahood is brought forth only by destroying all clinging through a realization of the truths of Maya and Sunyata. In the ultimate sense, the Compassion of Buddha arises not because He possesses an eye or heart which sees or feels the ocean of miseries that genuinely exist on this earth, but it arises in a most natural and spontaneous way. This spontaneous Compassion, a unique possession of Buddhahood, can be brought about only through a deep realization of Sunyata and complete identification with Totality.
Only through the total destruction of clinging can the ultimate Compassion be gained; only through negating Buddhahood is Buddhahood achieved. Because there are no sentient beings to be pitied, Buddha has the greatest pity; because from the very beginning no sentient being ever existed, Buddha "came down" to the earth to save sentient beings. Is this paradoxical? If it is, it is only because we are paradoxical, not the Truth. From the human viewpoint a paradox is something contradictory and disharmonious; but from Buddha's point of view it is harmony and unity.
Thus the Perfect Compassion of Buddhahood is an all-embracing and unconditioned Love, a Love that consists in and is identical with Perfect Wisdom, that arises not from any form of clinging, but from a total liberation from all attachments.
The Perfect Power of Buddha
The Perfect Power of Buddha is the greatest and purest power that can possibly exist, but it is not omnipotent. Buddha is all-knowing and all-merciful, but not almighty. If any being can be said to be almighty, this means that he is capable of doing anything he wills. In other words, an almighty being could kick this globe to Heaven like a football, thereby eliminating all the troubles and miseries on this planet in no time, if he so desired. But Buddha does not have this arbitrary power, nor did he ever claim to have it, although many other religions claim it for their gods. It should be plainly evident that all-knowledge, all-mercy, and all-power cannot possibly exist in the same being at the same time. An almighty and all-knowing God could not possibly be all-merciful as well; otherwise, his intention of creating this world, with all its resultant miseries and sins and its supposed eternal hells, etc., would become inexplicable and ridiculous; and as a result, his good conscience and wise foresight would also be reduced to a joke.
Buddha is mighty but not almighty. He cannot impose his will on anyone, nor can He perform or accomplish on someone's behalf something in violation of the Law of Cause and Effect. Buddha does not punish anyone or send anyone to an eternal hell. Such a thing would be impossible to an all-merciful Buddhal If anyone goes to hell, he goes there by himself as a result of his own evil doings. In the Buddhist scriptures there is no saying to the effect that Buddha will punish someone by sending him to hell should he disobey the will of Buddha. On the contrary, the spirit of Buddhism is to encourage people to go down into hell. As the compassionate Bodhisattva Ksitigarbha  said, "If I do not go down into hell, who else will go to save the poor creatures there?"
The blessing power of Buddha is like the sun, without which no plant could grow. But the growth of a plant does not depend entirely upon the sun; air, water, soil, and, most important of all, the seed itself, are also indispensable. The air, water, and soil are comparable to one's own efforts toward Enlightenment, and the seed is comparable to the Buddha-nature latent in one's own mind. The combination of all these different factors makes the attainment of Buddhahood possible. Lacking any one of them, Buddhahood would become very remote from us. In short, the Perfect Power of Buddha can give us great assistance and provide favorable conditions for our spiritual growth, but it cannot do everything for us. This is perhaps one of the major differences between Buddhism and other religions.
From the Mahayana viewpoint, though the Perfect Power of Buddhahood does not imply complete omnipotence, it is not too remote from it. The Mahayana Buddhist maintains that the Perfect Power of Buddha, like the power available from the sun, is infinite and inexhaustible; but the benefit that one can draw from it depends entirely upon one's individual capacity and effort. With a small magnifying glass one may focus enough heat from sunlight to ignite a match; but with more powerful lenses one may collect enough heat to warm an entire house. If the almighty power of God is understood in this light, there is no irreconcilable ground between Buddhism and other religions.
Mahayana Buddhists believe that the different teachings of the various religions are all beneficial and necessary for people of different capacities and perspectives. Some of these teachings may be of an "expedient" or "persuasive" nature, devised for the immature minds of the masses; others are truly the final teachings, only suitable, at our present stage of evolution, for a minority of highly endowed persons. But all religions have played their constructive roles in promoting human welfare and spiritual growth. As a Buddhist sees it, in the big family of divine doctrines there is a distinction only between the preliminary and the advanced, between the "expedient" and the final teachings, but not between the "right" and the "wrong" ones.