In the Book of Rites, Confucius gave three views on the issue of "the origin of rites". First, the first chapter of the Book of Rites deals with the The difference between Datong and Xiaokang. In the rapid turn of the world, rites came on the stage as a way to stop chaos; The second is the review of "the history of ritual system": Confucius traces the natural origin of ritual and its evolution from simple to complex. The third is to intentionally erase the diachronic and historical narrative of Confucian classics: saints imitate the displays from the Tian to make rites and music. It is necessary to follow the law of Tian to establish the ritual system, so the rites can follow the material situation and give play to the effect according to the situation. The ruler can also "hide" in politics, "do nothing at the center" and realize governance and achieve perfect state. By combing the three clues of the origin of Confucius’ theory of rites, we can clarify the main idea of the "Li Yun".