Yin-Yang and Wuxing had been involved into the system of Ba Gua (Eight Diagrams) so that the theoretical system of Feng Shui culture in Chinese culture.
The original meaning of Yin-Yang refers to the directions of the objects toward the sun light. The custom of worshiping the sun was prevalent among the primitives. On this account, it had gradually become into the most radical approach for the primitives to cognate the world. Make it short, according to these contrastive concepts Yin and Yang, the primitives found out many contrastive pairs, such as day and night in time, up and down in the space, sky and earth in the objects, men and women in human beings, living and death in the life, white and black in color, odd and even in numbers, hot and cold in the climate. All in all, all the objects about the life in the world are composed of two contradictory terms in the inner parts. However, these two contradictory terms could be mutually transformed under certain conditions.
The primitive concepts of Yin-Yang developed into a universal philosophical category through a long time. For example, although the discrimination and combination of Ying Yao and Yan Yao had been record in the Yi Jing, a part of Zhou Yi, these two terms were not contradict at all. After that, direct and simple Yin-Yang concept started to combine with the concept of Qi. The founder of the Taoist school, Lao Zi, had refined this concept as one kind of philosophy elaboration. In short, it can be expressed like: the sources which constitute all the things on earth are one kind of object called as Qi which is finely matter. When the Qi which is at the chaotic state divided into Yin-Yan and interact each other, all the things in the world produce and change.
This theory had been absorbed into Yi Zhuang. In the chapter of Shuo Gua, and Xi Ci, Yin-Yang has been considered as the basic concept Taoism. What’s more, it had been described by a systematic expression. On the other hand, it had vividly explained the process of producing Yin-Yang, and how an object in the world generated and evolved.
The theory of Yin-Yan explained in Zhou Yi has its own features. And it has played a critical role in the development direction of Feng Shui culture in Chinese culture. There is a famous event which happened in Qing Dynasty. It closely conforms to this theory in time.
According to the Record of the History, after Qin Shihuang, the first emperor of Qin Dynasty finished the national reunification successfully. He had toured the whole country for five times. What’s more, he had been to the southeast for 3 times and it was the longest tour. The origin for this is that some one told Qin Shihuang that there was Tain Zi Qi in the southeast. Therefore, Qin Shihuang hated to travel to the east.
However, in Chinese culture, the emperor had to deal with all kinds of government affairs so that he could not focus on the event of Tain Zi Qi. Thus, he narrowed the scope of travelling. Finally they located this kind of Qi on the Jin Ling (Nan Jing, Jiangsu province now). What’s more it was directly related to the geography of Jin Ling.
We all know that Liu Bang and Xiang Yu who had overthrow the Qin Dynasty did not come from Jin Ling. On the other hand, this story has told us that at least in Qin Dynasty, Qi has been considered as the core of Feng Shui culture.
The concept of Wuxing is ancient as the concept of Yin and Yan. And it maybe originated from that the primitives worshiped the number five. The main point of Wuxing is: the nature is composed of the five matters gold, wood, water, fire, and earth. All the phenomena in the human society are affected by these five matters. At the same time, these five matters are related to each other and restrict each other. It is used to explain the produce and evolvement of the nature and human society. For example, according to the development of nature, these five matters would be order like water, fire, wood, gold and earth.