By arranging the heavenly stems and earthly branches value of the year, month, day and hour of the lunar calendar when a person is born, it is inferred that a person's life is a noble and noble person, a blessing or a curse. Because the time of a person's birth is composed of four pairs of adults, month, day and hour, which is eight words, it is called eight characters or four pillars. In the Song Dynasty, eight-character divination was perfected, and Xu Ziping wrote "Notes on Three Lives of Luozi", starting with the combination of four pillars and eight characters, and then deducing the life span of people according to the principle of restraint of five elements. Therefore, the eight-character push is also called Ziping. Factor leveling is more precise and rigorous than other methods, and it is highly respected by the world. Since the Song Dynasty, it has been circulated in the ruling and opposition circles and passed down from generation to generation. Therefore, in the "Self-abuse Compilation", it is said that there are people who talk about life in the rivers and lakes, including Ziping, Five Stars, and the number set before the scope. Scholars are happy to ask, only Ziping. According to the Records of Ruizhou, Zou Yuanzuo, a warlock in the Song Dynasty, was proficient in the five elements. He tried to distribute land, water and fire in Jin Mu one day this year, and blamed his prosperity on him. He was punished by officials, nobles, horses and horses to test his life and wealth, whether he was rich or poor, or not. People in Beijing are scrambling to build doors and ask questions because they have money. Fujian Fuzhi also records that Zhan Yongda, a man of Amin dynasty, urged his parents and brothers to be noble and humble when he was born, knowing his own death date, and the prophet politely declined and then knew his death. It can be seen that the eight-character edge was popular in ancient times.