The divinatory symbols are composed of yin and yang, all of which contain heaven, earth and people. Lonely yin is not born, and lonely yang is not long. Every divinatory symbol will be born when yin and yang are copulating, and will die when yin and yang deviate, while the aunt's anode will turn yin and the cathode will turn yang. This is the mutual root of yin and yang. For example, Yang was born in the afternoon, Yin was born in the next month, and everything became an image.