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.

Section 9: "From antiquity until now, there has never been one who used two minds and achieved excellence."
"From antiquity until now, there has never been one who used two minds and achieved excellence."
This conclusion, drawn after citing numerous examples, is forceful: throughout history, no one who divided their mind achieved mastery in any one skill.
The power of this conclusion lies in its universality—"from antiquity until now," covering all historical experience—and its absolute negation—"there has never been."
Yet, we must ask: Is this conclusion too absolute$7 Do multi-talented individuals not exist$8
Master Xunzi’s response is that while multi-talented people exist, they achieved success in multiple areas not by dividing their attention among them simultaneously, but by being "Singular" about different objects at different times. When learning calligraphy, they devoted their entire mind to calligraphy; when learning music, they devoted their entire mind to music—each instance was an act of "Singularity," though the object of focus changed.
More fundamentally, true "multi-talented excellence" originates from "Concentration on the Dao." Once a person grasps the fundamental Dao, they can rapidly master any specific field—because the Dao permeates all domains. This is why "those excellent in the Dao encompass all things."