礼,是古代中国人所创造的极其复杂精致的表意系统。礼的要旨在“区分”;“区分”亦其时文明程度的标志。“流品”是士类用于区分的概念。士的流品论包含着等级论,但士所谓“流品”又较“等第”为模糊。士以其流品论为自我界定。严别流品,在明清易代这样特殊的情势下,是士保存其精英品性的要求,被赋予了语义的严重性。流品——阶级、等级论 Ceremony, is an extremely complex and sophisticated ideographic system created by ancient Chinese. The main purpose of the ceremony is to “distinguish” and “distinguish” the symbol of the degree of civilization at the time. “Flow ” is the concept of disabilities used to distinguish. The doctrine of the fluid product contains the theory of hierarchy, but the so-called “fluid ” and “” and other “vague ”. Scholars with their fluid products for the definition of self. Strict farewell to the flow of goods, in the Ming and Qing Dynasties such a special situation, is the preservation of its elite character requirements, was given the semantic gravity. Commodities - class, level theory