Five emperors' coins refer to copper coins with a round square hole. Ancient copper coins were cast in accordance with the principle of "outer circle inside" and "harmony between man and nature", which is the concrete embodiment of the ancient theory of Yin-Yang and Five Elements and has heavy cultural attributes.
In ancient times, there was a custom of using ancient copper coins to ward off evil spirits and attract wealth. Usually five copper coins are strung together, representing the strength of the five parties and five elements. The Five Emperors, in its original meaning, refer to the five emperors of East, South, West, North and China. They are five gods, endowed with five elements and five colors. Jin Mu is full of fire, water, earth, white, blue and red. The custom of representing the five elements and five emperors with five "outer circle and inner side" ancient copper coins has a long history.
On the basis of long-term medical practice, ancient physicians in China widely applied Yin-Yang and Five Elements Therapy in the medical field to explain the origin of human life, physiological phenomena and pathological changes, guide clinical diagnosis and prevention, become an important part of TCM theory, and have a far-reaching impact on the formation and development of TCM theory system.
It can be said that it is the ancient philosophy of China, and it is the ancient people's view of nature and world. Many scholars believe that China's ancient view of nature, especially the therapy of Yin-Yang and Five Elements, hindered the progress of science.
Natural philosophers in China often turn to this kind of natural philosophy when explaining phenomena. For example, electricity is interpreted as "yin and yang excited into electricity"; The earthquake is considered to be "the sun lies but does not come out, and the shade is forced but does not steam". Therefore, the extreme forms of empiricism and mysticism run through the whole scientific theory system in ancient China.