Four Pedigrees of Emperors or Dynasties under the Five Elements Conquering One Another

The concept of five elements——metal,wood,water,fire,andearth since ancient time caused the theory of the cycle movement of five elements which conquer one another.In the period of the Warring States,a person named Zou Yan from Qi,synthesized all the previous teachings of that theory and elevated them to their highest development.Since the Warring States to the early Western Han Dynasty,the theory of the cycle movement of the five elements has been the main theoretical tool for judging the orthodoxy or arrogation of a dynasty.Zou Yan,by using this theory,established a pedigree of Emperors or Dynasties.This pedigree did not accomplish the five element cycle,as it starts from Huangdi(earth) and ends at the Zhou Dynasty(fire).The Qin Emperor Shihuang who tried to prove that his rule obeyed the Heavenly Law and accepted Zou Yan's theory.Shihuang incorporated a water system,so that Zou Yan's pedigree would finish the cycle.The emperors of the early Western Han Dynasty also accepted Zou Yan's theory.A Scholar,Zhang Cang proved that the Han Dynasty's attribute is water,which was put forward by Emperor Gaozu.Gaozu-Zhangcang's pedigree implies that the Qin Dynasty is not in the orthodox system.The change of the theory started in the reign of Emperor Wendi,and was accomplished in the reign of Emperor Wudi.The new theory started with the Han Dynasty as earth,and brought the Qin Dynasty into the orthodox system.This theory became the final version of the five-element-cycle theory and was replaced by others at the end of the Western Han Dynasty.