Cheng Yi

程颐 is cited as a commentator on the Yijing whose readings explain how a line’s position, quality, and relation to other lines shape its meaning. Across examples involving return, correct conduct, withdrawal, and marriage, his interpretations make the hexagrams into guides to judgment and conduct; the translator also distinguishes these commentarial readings from his own explanations and from the text itself.

Interpretive Method

The commentary attributed to 程颐 repeatedly reads an image through the structure of its hexagram. In the account of Return, the first undivided line represents the way of the Superior Man, and the very idea of returning implies that its subject has deviated from that way. The second line is central and properly placed, but weak; its adherence to the first line compensates for that weakness, making its return admirable. These readings show how position and relation, rather than a line considered in isolation, determine the ethical force of an image.

The translator’s account of line interpretation gives this method a broader framework. The second and fifth lines occupy the centers of their trigrams, and their correspondence can represent a beneficial relation between a capable minister and a ruler or commander. The meaning of any line also depends on the hexagram’s subject. 程颐’s interpretations appear within that system: they explain why a particular image fits the line’s place and situation, rather than treating its words as a free-standing maxim.

Correctness, Restraint, and Political Judgment

In a commentary on the hexagram associated with brightness and adherence, 程颐 compares the docility required by correct conduct to that of an ox, and says it must be still more evident in a cow. The image makes obedience to what is correct central to good fortune. Here the animal is not simply decorative: its traditional quality of docility supplies a practical measure of how the subject should act.

His reading of Retreat similarly turns an image into advice about conduct under political pressure. The hexagram is linked to a time when unprincipled men gain influence and the Superior Man must withdraw. For the second line, the decision to retreat is represented as purposeful: the line responds correctly to the fifth, and both occupy central positions. The yellow color of the ox signifies correctness, reinforcing the discipline of withdrawal rather than haste. In the third line, by contrast, the subject becomes entangled with those below and allows familiarity to restrict movement; the commentary warns that they should be kept at a distance. The contrast makes retreat a matter of discernment and boundaries, not mere flight.

Images and Their Limits

The translator presents 程颐’s interpretations alongside a more skeptical assessment of the Yijing’s symbolic material. In discussing the sister of King Ti-yi, the Duke of Zhou’s image of the nearly full moon prompts a difference of emphasis: the translator welcomes it as a rare poetic moment, while 程颐 reads the moon’s incompleteness as a symbol and draws from it the principle that a wife should not eclipse her husband. The episode shows how commentary can turn a suggestive image into a normative explanation, and how the translator may preserve the interpretation while registering a different response to its literary quality.

The translator also resists attributing to the ancient text a fully developed theory of primary matter. He argues that such speculation took shape much later, in the Song period, and cautions against reading later cosmology back into the Yijing. This distinction matters for understanding 程颐’s place in the book: his explanations are presented as commentarial readings of particular images and line relations, not as proof that every later philosophical system was already present in the earliest text.