The principle of geomantic omen originates from Yin and Yang, which are two attributes that ancient sages originally represented nature. Everything in the world belongs to yin and yang, and yin and yang are everywhere. Heaven and earth are big yin and big yang, with yin in the yin, yin in the yang, yang in the yang and yang in the yin. Even the smallest thing has yin and yang properties. Yin and Yang are two instruments, which regenerate four images, so there are four directions, east, west, north, south, up and down. The middle is what we call the five elements, the east belongs to wood, the west belongs to gold, the south belongs to fire, the north belongs to water and the middle belongs to earth. Yang Gong created seventy-two dragons according to the five elements and Yin and Yang, that is, four noon in the south, Haizi ugly in the north, Yinmao Chen in the east and Geng Twelve Mountains in the west, which split the twelve mountains into two and became the twenty-four mountains now. Separated mountains are recorded in four dimensions: A, B, D, G, N, G, N and G. That is to say, in the practice of geomantic omen, 360 degrees on Sunday is divided into 24 points, and each point is 15 degrees, that is, 15 degrees on each mountain. The range of 15 degrees is too large to be accurate. According to the principle of Yin and Yang, Yang has Yang in Yin and Yang in Yin. It is inferred that there are five elements in the five elements, that is, Muhang contains Jin Mu's five elements of fire, water and soil, and Jinxing also contains Jin Mu's five elements of fire, water and soil. Therefore, Yang Gong classified every degree of 360 degrees on Sunday as a five-element attribute, and the degree had a five-element attribute. Just like the earth rotates 360 degrees around the sun, there are five elements every day, and it goes on and on. It is found in the practice of geomantic omen and combined with the theory that the complete five degrees and the fire, water and soil in Jin Mu will form a mountain, which is now the Yilong in the 72 dragons, that is, a mountain. This dragon contains the attributes of the five elements, including the qi of heaven and earth and the yin and yang of heaven and earth. Yi Long is composed of five degrees, so there are five elements in the mountain, which become the five elements of seventy-two dragons, and are recorded by Yin Na's five lines of sixty jiazi respectively. For example, Jiazilong and Ugly Dragon belong to Golden Sound, so they are both recorded as Golden Dragons. There are only 60 groups of 10 branches and 12 branches, and there are 12 dragons, which are recorded by the voice of 60 jiazi and 12. Add up to the five elements of seventy-two dragons. On the basis of 72 dragons' five behaviors, Yang Gong decided that it was a foregone conclusion. So there is no such thing as an empty dragon among the 72 dragons.
A large number of feng shui practice surveys have proved this theory, and data research has also proved the rationality of this theory.