Youzi said: "The purpose of etiquette is harmony. This is the beauty of the way of the ancient kings. Depending on the size, there are certain things that cannot be done. Knowing how to be harmonious and harmonious is not possible without etiquette." "Li", in the Spring and Autumn Period and the Warring States Period, generally refers to the rules, regulations and moral norms of slave society. Confucius' "Li", that is, "Zhou Li", etiquette, and rituals, also refers to people's moral norms. "harmony" means harmony, harmony and harmony. "The way of the ancient kings" refers to the way of governing the country by ancient emperors such as Yao, Shun, Yu, Tang, Wen, Wu, and Zhou Gong. "Si" means "property" and "harmony" here. The meaning of this sentence is that harmony is the most important thing in the application of etiquette. This is the valuable part of the ancient emperors' methods of governing the country. But just doing things in a harmonious way, no matter how big or small, sometimes doesn't work. This is Because harmony for the sake of harmony and not restraining harmony with etiquette is not acceptable.

Confucianism believes that the implementation and application of etiquette should be based on harmony. However, everything must be harmonious, or harmony for the sake of harmony, without the constraints of etiquette, will not work. Therefore, the deep meaning of "harmony is most important" should be understood as working under unified guidance and according to certain norms, so that everyone can get their own place, but there should be no discord between them. This is exactly the state of "harmony without difference" as Confucius said. Youzi pointed out that "harmony is the most precious", and its purpose was to ease the conflicts between different classes so that they would not break up and stabilize the social order at that time. but. Looking at this issue theoretically, we also feel that Confucius not only emphasized the importance of harmony in the use of etiquette, but also pointed out that harmony cannot be achieved for the sake of harmony and must be controlled by etiquette. It can be seen that Confucius's sum is not an unprincipled sum, but a rational sum.