Cosmological Construction and Rational Essence of the Original Functions of the *Book of Changes* Based on Divination Tracing

Section 5.3: Zhuangzi's Statement on "Yi Expresses the Way of Yin and Yang"

The positioning of the function of the Zhouyi by Master Zhuangzi (庄子) leaves behind a profoundly important statement. In the "Tianxia" (天下) chapter of Zhuangzi, when discussing ancient scholarship, it states:

"The Shi expresses aspirations; the Shu expresses affairs; the Li expresses conduct; the Yue expresses harmony; the Yi expresses the Way of Yin and Yang; the Chun Qiu expresses distinctions of names." (《诗》以道志，《书》以道事，《礼》以道行，《乐》以道和，《易》以道阴阳，《春秋》以道名分。)

"The Yi expresses the Way of Yin and Yang" (《易》以道阴阳)—the function of the Yi is to expound the Way of Yin and Yang and its changes.

Please note, Master Zhuangzi does not say here "The Yi expresses good or ill fortune," nor "The Yi expresses divination," but "expresses the Way of Yin and Yang." "Expresses" (以道) here functions as a verb, meaning "to speak of," "to expound," "to reveal."

What is Yin and Yang$41 Yin and Yang are the fundamental laws governing the operation of all things under Heaven and Earth—the alternation of day and night, the passage of cold and heat, the rise and fall of hardness and softness, the cycle of life and death; behind all change are the interactions of Yin and Yang. "Expresses the Way of Yin and Yang" means revealing this fundamental law.

Master Zhuangzi juxtaposes the Yi with the Shi, Shu, Li, Yue, and Chun Qiu, assigning a core function to each classic. Shi expresses aspirations, Shu records affairs, Li guides conduct, Yue achieves harmony, Chun Qiu rectifies names—none of these functions is "divination." The function of the Yi, "expresses the Way of Yin and Yang," is also not divination, but revealing the fundamental laws of cosmic change.

This is the definitive positioning of the original function of the Zhouyi by pre-Qin Daoism: The Yi is a book of Yin-Yang philosophy.