This paper discusses the original meaning of the idea xing and its extension in pre-Qin classical literature, from pictographic, phonetic, syntactic and philosophical approaches. Though the character xing is simply the form of a "crossroad," the original meaning of it should be "walking," according to phonetic analysis. In different paragraphs of different classics of the pre-Qin period, we have found that the character xing invokes different meanings such as road, act, moral conduct, queue, roll, trail, revolution, etc. in different textual contexts. Though it is not easy for us to rebuild the chronological development of these meanings, we can still see that all of them import value judgments at the root of the "meaning tree" which contains the spirit of rationalism: judging of right and wrong, and a sense of development and revolution. Based on these connotations, the notion wuxing used both in the "Hongfan" of the Classic of Documents and the "Wuxing" of the Guodian Chujian leads to new terms such as wufu "five fortunes," wushi "five moral behaviors," and shixing "alternation of moralities." Later on, the philosophers of the Yinyang-wuxing school even introduced the idea of wude zhongshi "the five agents taking turns to succeed one another," by which they emphasize the rotation of the five natural agents as well as the five virtues. That is, the terms de (virtue) and xing (walking) refer both to their literal and inner cultural meanings. This example reminds us that we should understand the meanings of these terms used in the ancient classics with a more comprehensive point of view instead of giving arbitrary conclusions inferred simply from their external form or speech sounds.