Abstract: When Chinese ancient ideologists propagandized their ethic s ideals, they often used metaphor or yuan lei(to invoke a precedent) to prove their ideas. The method is called yan dao by yan shi(provide several simple, c ommon and unde rstandable examples to prove ones ideas). This method was used by many ideologis ts, such as Confucius MO Zi, HUI Shi and GONG SUN Long etc. It would be signi fic ant helpful to understand the ideas of Chinese ancient ideologists exactly, if w e could understand the relations...