I Ching perceives reality (Tao) as a process of ongoing, repeated rise and fall of the two archetypical poles, yin and yang. Everything joins in the cosmic process. Thus, the nature of existence (Tao) is a cyclical, ceaseless motion. Yin and yang are therefore elements of change. If they were destroyed, there would be nothing by which changes could be perceived, and without change, also they would cease to exist.
Yin and yang set the boundaries for the cycles of change. While they are opposites, they are not of a different kind. They are rather two extreme poles of one whole. Nothing is only yin or only yang; everything is both. Although each wants to dominate, they cannot, because each includes within itself a part of the other. Consequently, when one arrives at its peak, it starts to decline, permitting the other to rise. It is a dynamic relationship. One is increasing, while the other is decreasing. When yang is taking form, yin is disintegrating, returning to the state of formlessness. Life and death, growth and decay, the cycle never ends. The ongoing flux between the two poles exists in everything. The yang forces of day, give way to the yin forces of night, and vice versa. It is a natural order based on a dynamic tension between yin and yang. The yin yang symbol is the essence of this equality, balance, and harmony. Dynamic tension between yin and yang results in balance. Handling the tension ends in harmony. Harmony is therefore not the absence of tension; harmony is created by balancing differences and handling conflicts. With balance and harmony, changes take place steadily and in continuous progression.
It is believed that yin and yang appeared at the beginning of time, when a flash of lightning split the cosmic darkness bringing light. Since then yin and yang are the only two cosmic forces that exist. Nothing has life except through them and all that is, contains both of them. Yin and yang relate to the first known world religion: shamanism. It perceived two worlds: a material and a spiritual world. The spirit world often threatened the material world, hence the shaman needed to balance the two worlds. In the 5th century BCE, a revolution in thought disputed the two world's unequal relation, and a new model with two equal worlds emerged. At the same time, the Chinese developed technology to tame the rivers and the risk of floods, and the earthquakes and the risk of drought. Chinese people have historically suffered serious floods, caused by the Yellow River bursting its banks, inundating their homes and fields. However, with the new model humans no longer were at the mercy of the gods. People could, through their own efforts rightly applied, interact with nature and influence the spirit world. Thus, the yin and yang theory emerged from human interaction with nature. This interaction is consequently the basis for understanding the traditional Chinese view of how harmony and balance are created.
The yin yang forces are linked so that the welfare of one affects the welfare of the other. If the universal yin yang balance is upset the Earth is distressed, resulting in natural disasters that negatively influence all. If people's yin yang balance is disturbed, they will negatively influence the balance of their surroundings, causing harm to all parts of the universe. It is therefore important to maintain balance personally and cosmically. In this way, the Taoist saying, "You are the universe and the universe is you," makes sense. Everything in the universe is interconnected, and yin and yang are a whole. Yang relates to form and the process of taking form, while yin refers to matter/energy, which takes form and dissolves into formlessness. Matter-energy cannot exist without a form and there can be no form without matter-energy. When we experience our everyday world, mentally perceiving it to have an objective self-existing form, it is the phenomenal yang world we see. However, when we stop projecting our form upon the world, we become aware of yin and its formlessness. It is a change from observing forms to see that of which they are forms. Thus, yin and yang are diverse ways of experiencing and knowing the same world. Yang is based on rationality and reason, while yin is based on intuition and emotion.
Yin and yang are not good or bad; they just are, and as a consequence, the cosmos is. This perception differs from the Western worldview, which sees dark yin as bad and light yang as good. However, it is a dualist and biased perception. It falsely presents a value choice between two opposites: men are superior to inferior women; white people are better than people of color; and humans are more important than nature. This dualist view has permitted white man to dominate women and people of color, and exploit nature, causing cosmic imbalance. To recreate balance, we must include opposites as equals, without any value assumption. In the holistic Chinese philosophy, opposites simply exist and reflect the eternal yin and yang fluctuation. Yin and yang are therefore not moral values. One is not better than the other. What is good is balance between the two, while imbalance is bad. The aim is to balance the two forces, because any excess causes crises. We therefore cannot separate yin and yang; we cannot understand them independently: we cannot perceive day without night.
Consequently, everything in the universe is made up of yin and yang. Yang relates to that which is hot, dry, light, and active. It manifests in fire, sun, mountains, spring, summer, day, surface, gods, heaven, men, and life. Yin relates to that which is cold, dark, passive, and wet. It manifests in water, moon, rivers, floods, trees, autumn, winter, night, interior, spirits, earth, women, and death. Yang implies what is expansive, aggressive, and demanding. Yin corresponds to what is contractive, responsive, and conservative.
People also have both yin and yang forces, but men are more yang, and women more yin. In Chinese belief, certain things are given at birth, but nothing else is fixed. Thus, our fate is in our own hands. If we take control of our lives by improving our personalities and behaviors, we can change who we are. Since not all would choose the same, it will generate differences. Hence, Chinese philosophy celebrates diversity. This is opposite to the Western obsession with making all alike. The West needs one model that explains all. When they meet diverse models, they ignore, suppress, ridicule, or eradicate the alternative. Yet, the drive for uniformity or oneness will lead to an even greater diversity, since the opposite force will reappear as a natural part of reality.
Due to differences among people, there is always the potential for disagreement leading to conflicts and violence. Instead of removing disagreements, we must try to create balance by holding powerful opposite forces in a dynamic tension. Such tension gives energy. If the energy is not used to find a balance, it can be destructive. Yin and yang are consequently about conflict resolution. It is unwise to pretend that conflicts do not exist or they will go away. The rise and fall of powers is as natural as the rise and fall of summer. Trying to allow yang to suppress yin, is foolish. It leads to chaos and crises, while ultimately the yin will rise. It is equally destructive to be totally yin. To use or to be only one aspect of the twin forces is unhealthy. Denying the opposite is to store up troubles for the future.
Conclusively, everything in reality is both yin and yang. To deny this is unwise and it can lead to crises. Handling contradictions within, by seeing them as a natural part of who one is, is often a great relief. It helps us realize that these issues are not inconsistencies, only aspects of two opposing forces at work within all of life. Accepting this as being natural is a way out of the dualist either-or trap and the inner contradiction.