Yijing, Chinese 易經 yìjīng, also I Ging, I Ching; literally “easy to pass by”: The Book of Changes. Das Buch der Wandlungen. In its actual form written in the 7th/8th century B. C., probably based on much older precursors. It is a crucial text for the Chinese philosophy and metaphysics.
The changes are described by 64 hexagrams passing through every form of existence. These hexagrams consist of a combination of two trigrams (Chin. 八卦 bā guà) leading to the number of 64.
In the Yijing the essential core principles of the Chinese philosophy and the metaphysics were already recorded, e. g. the principle that the regularities of the microcosm correspond to those of the macrocosm as well as the dual world principle of yin and yang (陰陽 yīnyáng). The Yijing is also prefered to be used for oracle purposes.