In China's calendar, A, B, C, D, E, Ji, G, Xin, Ren and Gui are called "Ten Heavenly Stems", while Zi, Ugly, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu and Hai are called "Twelve Earthly Branches".
The two cooperate with each other in a fixed order, forming the discipline of cadres and branches. In Ci Yuan, it is said that "dead branches" are meaningful to trees. Heavenly stems and earthly branches formed a unique calendar in China to record the year, month and day. In the Book of Changes and the system of traditional Chinese medicine, heavenly stems correspond to a lot of related information, such as geographical location, viscera and other images of everything.
origin
"Spring and Autumn Life Calendar": "The heavens and the earth are open, and everything is turbid. According to yin and yang, the celestial body begins in the field of the North Pole, the terrain begins in the sky of Kunlun, and the morning glory begins in the five latitudes of the sun, the moon and the sun. Forty-five thousand years, the sun, the moon and the five latitudes take turns. When the emperor went out, it was called' defense against five', and the thirteen brothers continued to rule each other. Ride the wind and rain to catch the sun and the moon. Set the astronomical phenomena, instruments and places, and set the year and month for the dry branches, totaling 18 thousand years old. The emperor was traced at the foot of Kunlun Mountain in Zhuzhou. "
"Sansheng Huitong": "The husband is still a wooden worker, strong and yang; The wood branch is weak in yin. In the past, Pangu's way of tomorrow turned Yin and Yang into three talents. After the first emperor divided heaven and earth, there was heaven before there was land, and he lived a miserable life because of gasification. Therefore, after Pangu's rule, the emperor's surname was thirteen, which means that the heavenly spirit was indifferent and did nothing, only vulgarized himself and dated it by its branch name. "