20th WCP: Yin and Yang: the Nature of Scientific Explanation in a Culture

To a Western eye, or even to a contemporary Eastern eye, many explanations given under the doctrine of yin and yang combined with that of five phases (wu-hsing), apparently intended to be scientific, would seem either absurd or too arbitrary at first sight. An intriguing fact, however, is that the doctrine of yin and yang and that of five phases (hereafter YYFP) has prevailed until quite recently in almost all the areas of Far-Eastern cultures including medicine, astronomy, music, dance, architecture, geomancy.

In this essay, I pay attention to the questions such as how YYFP functioned as an alternative to the causal way of thinking, and what it is to be a scientific or theoretical explanation in a culture. I also consider the question of whether a scientific concept becomes metaphorical when it is superseded by an alternative organizing concept. Let me begin with the development of the concept of YYFP, as you may not know in the first place what YYFP is.

Until around the 4th century B.C., yin and yang were current words for "sunshine" and "shade" and were used separately from the five phases of change. Soon after, they came to be included in the six ch'i (six powers or forces) of Heaven. The six ch'i refer to wind, rain, dark, light, yin and yang. Yin and yang as parts of the six ch'i are now powers that would balance the order of nature inducing proper seasonal changes and controlling precipitation or wind.

And yet, it was not until the Warring States (403-222 B.C.) that yin and yang became two opposing forces generating everything in the universe. The concepts of yin and yang as two fundamental forces are most conspicuous in I Ching (the Book of Changes) being epitomized in the statement, "The successive movement of yin and yang constitutes the Way (Tao)" ("Commentary on the Appended Phrases", part I, ch. 5). As they settled into the categories of opposing forces, they came to provide an explanatory apparatus applicable to opposites, contraries, and hierarchical pairs. For instance, heaven, sun, fire, flying, running, being round, and male, on the one hand, belong with the force of yang; earth, moon, water, hibernating, hiding, being square, and female, on the other hand, belong with the force of yin.

The supposed explanatory power of yin and yang grew enormously when combined with the doctrine of the five phases. The doctrine of the five phases provides a system where everything is categorized into one of five groups. Everything in the world is thought to follow the cyclic changes of fives, and things in the same phase are correlated to each other in such a way that they can be observed together in natural or social phenomena, and people are thought to act in accordance with the correlations among things.

The principle that governs the cyclic changes is either generation or conquest:

wood generates(catches) fire, fire (reduces to) soil, soil (in which) metal (forms), metal (upon melting is liquidified) water, and water (nourishes) wood . . .(in this case, the cyclic order of fives is wood, fire, soil, metal, water); or wood conquers (digs) soil, metal (cuts) wood, fire (melts) metal, water (extinguishes) fire (in this case, the order would be soil, wood, metal, fire, water). The order gives a rule to interpret changes and even to predict (or anticipate) what would come next. It also provides heuristics by which people can remedy problems they have. For instance, if one has a problem with one's liver, which belongs to the category of wood, the treatment, given the second order of fives, would be attempted by strengthening the lung, which belongs to the category of metal, which overcomes wood by cutting.

On the other hand, the relations among numerous things belonging to the same phase are often based on prima facie or symbolic similarities. You may get a glimpse of the basic idea of the five phases from the following. I use the first order here:

	Wood	Fire	Soil	Metal	Water
Direction	North	East	South	Center	West
Season	Spring	Summer	Late summer	Autumn	Winter
Viscera	Liver	Heart	Spleen	Lung	Kidneys
Sense organ	Eye	Tongue	Mouth	Nose	Ear
Color	Green	Red	Yellow	White	Black
Time	Morning	Noon	Afternoon	Evening	Night
Feeling	Anger	Joy	Woe	Sorrow	Fear
Taste	Sour	Bitter	Sweet	Hot	Salty
Voice	Calling	Laughing	Sighing	Sobbing	Moaning
Number	8	7	5	9	6
Creature	Scaly	Feathered	Naked	Furred	Shelled
Ch'i	Wind	Hot	Wet	Dry	Cold

It is not clear what kind of principle or rule governs the groupings. If everything in the universe belongs to one of the five phases of change, there must be some principle by which we classify things. But we do not know by what criteria things are thought to be in the phase of wood and under the power or virtue of wood. In some cases, we may observe intuitive similarities, but in many cases the groupings seem quite arbitrary, and even absurd.

In Lue-shih ch'un-ch'iu (the records of the events during the Spring and Autumn period<722-481 B.C.> by Lue-shih in the 3rd century B.C.), we find a principle to the effect that similar things respond to each other:

If things are of the same kind, they are more likely to harmonize. If they are in the same ch'i, they unite, and if the sounds are alike, they make harmony. Thus, if we strike the kung note, then another kung sound will respond to it, and if we strike the chiao, then another sound of chiao will answer it. If we pour water onto the flat land, the water will be running toward the wet part, and if we set fire on the firewood, fire makes its way to the dry part. (1)

The principle that similar things respond to each other does not purport to give a systematization of natural and human phenomena providing the greatest possible general principle under which less general ones are to be subsumed. Even though the systematization by laws of causation also presupposes similarity among events, the similarity condition runs diachronically, whereas it runs synchronically in the case of YYFP. That is, causes that are similar to each other in the relevant respects will produce effects that are similar to each other in the relevant respects. Instances of causation are grouped together by causal laws based on certain sorts of similarities between the instances. A similarity relation runs through similar instances of causation occurring in different times. The use of the principle of similarity in the system of YYFP generates a harmonized world that is ever more enlarged as objects are categorized in accordance with the principle. It is the world of order where all people and nature, according to their similarity relations, go well with, or respond to each other in a harmonious way. This harmonized world is distinct from the world of order where all events or occurrences in time are brought under laws that would relate different events in terms of causality. Harmony and order come about in the former as assimilated things grouped together in one of the fives move in ever-lasting cyclic order, whereas in the latter they lie in lawfulness where similar cases are subsumed under a general law. It is intriguing to note that a similar mystery prevails concerning what the responding or assimilating relation between things amounts to, and what the causal relation between events is. In both cases, a uniformity of nature is presupposed. But it is not clear if it is by their internal nature that things respond to certain other things, or if the similarity relation is determined by a culture or what Wittgenstein called 'the form of life'. As it is not clear whether causality belongs to nature, so it is not clear if there is inherent an assimilating power among things.

The similarity relation in most cases is not natural but dependent on a particular background system. The similiarity relation that has been thought of as running through Heaven, king, husband, and the noble was made possible by a patriarchal monarchy. Insofar as the similarity relation is not natural, the concepts of yin/yang and the five phases take on the characteristic of metaphor. However, the more deeply the metaphors are rooted in the background system, the more powerful they become, to the extent that they are taken to be natural and scientific. Once the similarity relation is assumed and once things are grouped according to whatever similarities they might have, the only thing you can do is to behave as the order thus generated dictates.

Now, how is the concept of yin-yang related to the doctrine of the five phases? Tung Chung-suh thought that yin and yang as two opposite material forces help the workings of the five phases. Small yang accompanying the wood phase helps activate the birth of Spring; large yang accompanying the fire phase, the growth of Summer; small yin accompanying the metal phase, the harvest of Fall; and large yin accompanying the water phase, the storing and the hiding of Winter. (2) They were considered two mobile forces that made the Five Phases go round trying to conquer each other while reinforcing their power by activating things of the same kind.

As the YYFP provided explanations about what happens in both the natural and the human worlds, including the human body, the extent the YYFP claimed for its explanatory force was excessively enlarged, with arbitrariness accordingly increased. Arbitrary as it may be, we find, in the explanatory system of YYFP, a similar craving for reduction and explanatory efficiency that permeated the development of modern Western culture, where extensive causal explanations are sought. Once you adopt YYFP, it gives you a simple and convenient way of finding an explanation by relating the thing or event to something else that is similar in a certain aspect, by categorizing it into yin or yang (or one of the fives). By way of analogy, the thing or the phenomenon to be explained acquires the properties that something it was related to allegedly has. Since they belong to the same category, they are governed by the same force or virtue.

By being located in the huge network of expanding relations and in the system of assimilations, things and phenomena related to them are thought to be understood and explained. People have lived within this system with its conceptions of disease, cure, life, death, happiness, justice, reality, and so on, that the system has prescribed. Within this framework, one seeks to find a possible relation things or properties observed in an event might have to other things. If one finds to what category they belong on the basis of similarity, then one claims to have an explanation of their occurrence, and even predictions about their future occurrences and behaviors (in the case of humans). That's how the system of divination has developed. Instead of seeking possible causes and effects, one seeks a possible similarity relation.

This attitude hampers causal thinking, because if the system of assimilations works well, there is no need to wonder about the cause. But what is it for the system to be working? When all the sciences a society has and virtually everything in it were organized on the basis of YYFP, it is quite likely to work. It is made to work, as people live out the rules the system is built on. And as people live that way, the system, in turn, is consolidated. Insofar as the system of assimilation is working, explanations in terms of YYFP are counted good or at least relevant and acceptable. It is like the situation where causal-mechanical explanations are considered genuine insofar as the system (whether culture or science) based on mechanical physics is working and taken to be genuinely scientific.

At this point, a question of circularity concerning the relevance of explanation or the criteria of good explanation, as well as a question about the actual use of causal concepts in Eastern civilization, may arise. First, what is it to determine that a given explanation is relevant or good? What does it mean to say something is explained? What difference is there between being explained and not being explained? Can there be a universal model of scientific explanation as Hempel or other philosophers of science attempted to establish? Can there be a model of explanation in general against which all these questions could be settled? Can something be an explanation in one context and not in another context, whether the context is to be a culture or a disciplinary area or a form of life?

These questions are worth considering. It is because YYFP has prevailed in some cultures for 2,000 years, providing a rational ground for various human and natural phenomena, even if explanations given under the YYFP cannot be counted as scientific from the modern Western point of view. Chinese medicine is still very widely practiced in the East. This tells us that what determines for a society or culture the relevance of a given explanation is a knowledge framework a culture or a society has. It determines not only what to count as a good explanation, but also what calls for an explanation. In Chinese medicine, diseases are said to be the imbalance between the two ch'is, yin and yang, in the body. Explanations appealing to the movements of yin and yang are relevant and would serve people's need in that context. The questions for which the explanations are provided might not even appear in the context of Western medicine.

But if the relevance of an explanation is determined by the knowledge framework that first generated the question, what is the point of demanding an additional explanation within the framework? Even if additional explanations are given, what kind of information, or knowledge, or understanding would they provide in addition to the information that the original knowledge framework would generate? If we live within the framework of YYFP, the causal explanations given with regard to the question, "Why are birds flying?" seem to be superfluous. Birds as the feathered and belonging to large yang are readily correlated to flying, which also belongs to yang. If we live with the causal-mechanistic world view, causal-mechanistic explanations would be expected, and given with reference to the readily existing framework of knowledge (i.e., physics, chemistry, etc.). There seems to be an unavoidable circularity here in that you already presuppose what you ask.

The problem of circularity puts us in a situation where the possibility of establishing a general theory of explanation is called into question, because it is not the general theory that determines what counts as an explanation, but the knowledge framework you already presuppose. If the relevance of explanation is determined by reference to the background knowledge framework, how can the relativity of explanation be dealt with? I seem to face the problem of incommensurability. I do not have a clear answer to this question. But, I think, the explanatory circle breaks down when one knowledge framework clashes with another. Various factors will determine which one dominates the other. I don't think that it is just a matter of explanatory power, since we cannot determine that power on a neutral basis. Political, economic, or even military powers could also be factors. Once the circle breaks down, and the other criteria of the relevance of explanation dominate, then the old concepts used in old explanations become metaphors. They no longer squarely fit into the newly changed forms of life of people, which are based on new technology and new science.

The ideal YYFP tends to achieve is cohesiveness and appropriateness within things (including humans and nature) in the universe, whereas the ideal of a causal-mechanistic system is necessity among phenomena and events. Finding a proper place in and proper relations with the surroundings is most important in the former, while finding exact causes and reasons is required in the latter. As you are adapted to the forms of life based on modern science and on the political ideal of free and autonomous individuals as atomic units, you begin to demand explanations in the face of 'why' questions that would provide you with the necessity (instead of the approximate correlation of things involved) of some occurrences and behaviors in terms of exact causes and reasons. You see people around you as objective individuals to deal with on an even ground, not as someone to be assimilated or differentiated based on a certain order and relations. The concepts of yin/yang and the five phases become vague and remote while losing their grip on peoples' lives. However, it seems that the development of science and technology does not always bring a change in peoples' worldviews as dramatic as it would have done in their own fields. Insofar as people still hold to the old worldview and have the old attitude toward other people and nature, YYFP may have explanatory power, though on a metaphorical level. This would explain how it is possible for the two radically different systems to coexist as they do in the East.

My claim that the development of science and technology could be made independently of the general worldview of a society may also be supported by the scientific and technological inventions in Eastern Civilization, which would not have been possible without applying the concepts of cause and effect. The use of causal concepts in the East has not added to building a comprehensive scientific framework that would function as a paradigm of thought influencing the whole culture on a large scale. The same point can be made even of Western culture. Recent developments in quantum physics, biology and information science have put us in a position where we question the uniqueness of the causal-mechanical model of science. But these developments, even though sciences based on non-causal concepts might dominate in the culture, would not eradicate the causal way people have viewed the world and themselves, but only relegate the concept of cause to the realm of metaphor, a rhetorical way of putting things. The concept of cause then would no longer be a scientific concept, but would still be alive in the culture. What brings a change in the general worldview then? This would be the question I still have to ask.