Christopher Gait - The Forest of Changes: The Jiao Shi Yi Lin, a Han Dynasty Divination Manual

The book is traditionally attributed to Jiao Yan Shou , courtesy name Jiao Ga n , who came from Liang (modern Shang Qiu , Henan) and was a tutor in the household of the Prince of Liang (early 1 st century BCE). He was a scholar and official, reaching the rank of district magistrate in Xiao Huang (near modern Kai Feng , Henan). However, some scholars suspect that the book was composed later, perhaps in the late Western Han, perhaps even somewhat later. I am inclined to agree with those who attribute the book to Cui Zhuan ( ), a scholar and official who was active in the time of the Wang Mang interregnum (9 - 23 CE). It is also my contention that much of the text is a divination manual specifically designed for merchants. How that fits in with the books scholarly provenance remains to be discovered.

Yi Lin literally means a forest or grove of changes. The book consists of 4096 verses. The verses represent all the possible combinations of the sixty-four hexagrams of the Book of Changes (Yi Jing/I Ching), thus 64 X 64 = 4096. When divining using the Yi Jing the figure may be unchanging (hexagram 50 remains 50, for example), or can have one or more moving lines which change it into another hexagram (16, third and fourth, lines changing, becomes 8). In this edition of the Forest of Changes that would be described as 16 - 8, and the text is: 16 - 8 Even a ravenous tiger, Will not eat a spiny hedgehog. Yu the Great carved out the Dragon Gate .

Avoiding misfortune and eliminating calamity, The people attain peace. This verse has several typical elements of the Forest. For one, there is a bit of folk wisdom on tigers and hedgehogs. Then comes the reference to Yu the Great, tamer of floods and founder of the Xia Dynasty. The verse uses an image from Chinese mythology in which Yu is supposed to have carved out a mountain as part of his herculean labors changing the flood pattern of China. Later diviners made use of various techniques to determine one or both of the hexagrams for an Yi Lin reading.

These often included drawing trigram images from the world around them and the events they were inquiring about and using a system to associate hexagrams with each hour. The Song Dynasty Yi Jing scholar Shao Yong is said to have used the Forest of Changes as part of his system of Plum Blossom Numerology.