Yin & Yang : are two primal forces controlling the whole of the universe according to Chinese philosophy. It is thought that everything can be categorized by this balancing system of Yin and Yang. Indeed everything from people, houses and animals, to nations continents and the entire universe, may be determined by the balance or lack of balance of the Yin and Yang. The ideal balance of Yin and Yang can be summarized in this diagram. The white (Yin) part of the diagram increases as the black (Yang) part decreases. When one part is at its height then the other is at its lowest ebb. Sometimes it is assumed that Yin is female and Yang male, however, this is not strictly true. For example, even though Yin is thought of as a predominantly feminine force, men can still possess it too.
Within Yin is the seed of Yang and vice versa, and as such, they form two complementary, yet also opposing forces. Together Yin and Yang make a whole, neither one is more important than the other. Below are some examples of how Yin and Yang appear and the opposing natures of these forces.