Zhu Xi and the Song masters

The rules for changing lines and the 'square within the circle' diagram used on this site come from the twelfth-century philosopher Zhu Xi and his predecessors. Knowing them explains where today's ways of reading the Changes come from.

Why Zhu Xi

FactFrom 1313 to 1905 China's civil-service examinations were based on the Four Books with Zhu Xi's commentaries; Joseon Korea made his thought its state philosophy, and Tokugawa Japan adopted his school as official learning. His Original Meaning of the Zhouyi and Introduction to the Study of the Changes remain among the most cited commentaries.

Our viewZhu Xi is little known in the West, and in China often reduced to one misread slogan. We want to restore his stature.

Compass and square

Compass and square stand for rules. Mencius said that without them even a skilled craftsman cannot draw a circle or a square. Shao Yong's Earlier Heaven diagram—a square inside a circle—was placed by Zhu Xi at the beginning of his commentary. Confucius at seventy 'followed his heart's desire without overstepping the square': not a constraint imposed from outside, but desire that has absorbed measure—the highest discipline.

Six centuries in one table

Thinker	Dates	Core idea	Link to the Changes
Zhou Dunyi	1017–1073	From the Supreme Ultimate to humanity; stillness without selfish desire	Diagram and Penetrating the Changes built on the Yijing
Shao Yong	1011–1077	The cosmos in numbers	Earlier Heaven diagrams
Zhang Zai	1020–1077	One vital energy; 'all people are my siblings'	Hengqu commentary
Cheng Hao	1032–1085	Humaneness as one body with all things	Moral readings of hexagrams
Cheng Yi	1033–1107	One principle, many manifestations	Yichuan commentary (1099)
Zhu Xi	1130–1200	Principle and vital energy; investigating things; the Four Books	Original Meaning and Introduction (1186)
Lu Jiuyuan	1139–1193	The mind is principle	Opposes fragmented study
Wang Yangming	1472–1529	Knowledge and action are one	Read the Changes in exile at Longchang
Dai Zhen	1724–1777	Principle lies within feelings and desires	Philological critique of Song metaphysics

'Preserve heavenly principle, extinguish human desire': the history of a misreading

ConsensusFor Zhu Xi, 'human desire' meant excessive, partial, self-serving desire—not ordinary needs; he said explicitly that eating and drinking are heavenly principle, while demanding delicacies is human desire. The phrase was later used as a slogan to repress individuals, a historical misreading that critics such as Dai Zhen already attacked.

For managers the lesson is that the question is never whether there is desire, but whether it is 'measured'—what the Doctrine of the Mean calls harmony: feelings arising and each hitting the right measure.

The mean: China, Greece, Rome

Every line of the Changes asks: what is excess, what is deficiency? The Song masters made this a philosophy. Europe asked the same from Aristotle's mesotes and Horace's aurea mediocritas; the Buddha taught a middle way. The difference is that the Yijing's centre is dynamic, shifting with the time—hence the 'timely mean'.

Eight key concepts

格物 gewu	Investigating things to exhaust their principle: get the facts straight before deciding.
理 li	Principle: the order and reason of things.
气 qi	Vital energy, the stuff of things; principle inheres in it.
太极 taiji	The Supreme Ultimate, the highest unity: 'in the Changes there is the Supreme Ultimate'.
心 xin	Mind-heart, awareness and agency; for Lu and Wang the mind is principle.
欲 yu	Desire is not evil in itself; excess and partiality are.
中庸 zhongyong	The mean: neither leaning nor inclining, just right—and changing with the time.
理学 lixue	Neo-Confucianism of the Song and Ming, centred on the Four Books and the Changes.

A decision map: six contemporary dilemmas

Accept a lucrative offer that conflicts with my values?	Zhu Xi: distinguish rightness from profit; rightness first, and profit follows within it.
Stick to the plan or adapt?	Cheng Yi: change with the times to follow the Way—the route changes, the direction does not.
Research first or act first?	The tension between Zhu Xi's 'investigating things' and Wang Yangming's 'unity of knowing and acting': clarify the critical facts, then correct in action.
Strict or lenient with the team?	Hexagram 37, line 3: better firm than lax—but warm.
Should I want more?	Hexagram 41's image, 'restrain anger and desire': curb excess, don't deny desire.
How to face failure?	Hexagram 24, 'return from a short distance': the sooner the drift is admitted, the smaller the cost.