- Chinese/Japanese: 易經 (Yìjīng / eki kyou)
The Yìjīng, often known as the I Ching or the Book of Changes in English, is the most ancient Chinese text discussing yin and yang, and the nature of the cosmos.
Believed to be a divination text from some much earlier period, its author and date unknown, the Yìjīng was taken up in the Han Dynasty as thinkers attempted to create a more coherent, complete, account of the fundamental nature of the universe.
The core of the text consists of 64 hexagrams, each comprised of a pairing of two of eight possible trigrams. The trigrams consist simply of a set of three broken or unbroken lines, with eight possible combinations (e.g. two unbroken and the third broken, or one broken and the second and third unbroken, etc.). Each broken line corresponds to yin, and an unbroken line to yang; thus, six unbroken lines represent Heaven, which is comprised purely of yang, six broken lines represent the Earth, which is comprised only of yin, and all other combinations represent all the multifarious things in between. Each of the sixty-four hexagrams is accompanied by a commentary.
Combined with concepts of the five elements (fire, wood, earth, metal, and water), the Yìjīng thus serves as the foundation for a conception of the universe as based in yin and yang, articulated by scholars of the Han Dynasty. Later figures such as the Song Dynasty thinker Zhu Xi would expand upon this, to articulate a universe comprised of qi, according to the universal principle li (principle).
- Conrad Schirokauer, et al, A Brief History of Chinese and Japanese Civilizations, Fourth Edition, Cengage Learning (2012), 58-59.