Section 1: The Dialectic of "Two-ness" (Liang) and "Singularity" (Yi)

A Deep Study of Xunzi's 'Jie Pi' Chapter: On the Cognitive Foundations of the Mind—Emptiness, Unity, and Tranquility

This paper provides an in-depth analysis of the core proposition in Xunzi's 'Jie Pi' concerning the nature of cognition: 'How does man know$41 By the mind. How does the mind know$42 By being empty, unified, and tranquil.' It systematically interprets the dialectical relationship and philosophical implications of 'emptiness' (xu), 'unity' (yi), and 'tranquility' (jing) in cognition, tracing their ancient intellectual origins to reveal the systematicity and sophistication of Pre-Qin cognitive theory.

Tianwen Editorial Team February 16, 2026 58 min read PDF Markdown

Following "Emptiness," Master Xunzi discusses "Singularity":

"The Mind has never been without two-ness (liang 兩), yet there is what is called Singularity (yi 壹)."

Liang means simultaneously cognizing multiple objects. The Mind is never limited to cognizing only one object; it always faces multiple streams of information and objects concurrently. This is the natural state of the Mind. Yet, Master Xunzi, while acknowledging that "the Mind has never been without two-ness," posits the requirement of "Singularity."

"The Mind is born with knowledge, and with knowledge comes differentiation (yi 異); differentiation means simultaneously cognizing both; simultaneously cognizing both is two-ness (liang); yet there is what is called Singularity; not allowing that one thing to harm this one thing is called Singularity."

Step-by-step analysis:

First Level: "The Mind is born with knowledge"—The Mind innately possesses cognitive capacity.

Second Level: "With knowledge comes differentiation"—Cognitive activity produces a sense of distinction regarding different objects.

Third Level: "Differentiation means simultaneously cognizing both"—What is called "differentiation" is the simultaneous awareness of multiple, distinct objects.

Fourth Level: "Simultaneously cognizing both is two-ness (liang)"—Simultaneously cognizing multiple objects is "Two-ness."

Fifth Level: "Yet there is what is called Singularity"—But the Mind still requires "Singularity."

Sixth Level: "Not allowing that one thing to harm this one thing is called Singularity"—Preventing the cognition of that one object from obstructing the cognition of this one object is called "Singularity."

Here, "Singularity" does not mean "knowing only one thing," but rather "concentrating on the one object currently being known." Although the Mind faces multiple objects simultaneously, when specifically cognizing one object, it can focus its attention without being disturbed by the others—this is "Singularity."