Commentary on the Book of Changes (Yichuan Yizhuan)

Introduction

Cheng Yi’s main written work, a line-by-line commentary on the Book of Changes (Yijing); its preface is dated 1099, during his political exile. Instead of treating the 64 hexagrams as tools of divination or number speculation, he reads them as images of situations in human life – above all in government and in the relationship between ruler and minister – and asks how to act rightly in each. Behind all change he finds principle (li); the preface states that substance and function have a single origin. Zhu Xi built on the commentary but placed more weight on the divinatory origins of the text, and the Cheng–Zhu reading of the classics became orthodox in late imperial China.