The article systematically examines the various functions of the word"Shi"in the On the Uniformity of All Things,including its function as an indicative pronoun,the meaning of"correct"as an adjective,its function as a copula as a judgment word,and its role as a morpheme and a verb.It also focuses on the current research on the"yinshi"issue and ar-gues that the"yinshi"in the On the Uniformity of All Things has a dual nature,in which"shi"has both a positive meaning of"natural"and"inborn"and a negative meaning of"unnatural"and"against one's nature"that is derived from"right and wrong".