Skip to content

Yijing Research

The Yi in the Han: Time, Change and the Yilin

Imagine standing in front of a shelf containing a text for every possible pair of hexagrams. You begin with one hexagram, look for another, and there is a short verse waiting at their intersection. That is, in broad outline, how the 《焦氏易林》 Jiaoshi Yilin, “Mr. Jiao’s Forest of Changes,” is arranged. It offers 4,096 positions, the product of sixty-four multiplied by sixty-four. One old oracle has become an entire forest of possibilities.

A new world of correspondences

The Han period saw an enormous expansion in the ways people connected the Yi with the world around them. Hexagrams and trigrams could be linked to months, seasons, directions, the Five Phases 五行, the Stems and Branches of the calendar and other organizing systems. Such arrangements were not simply decorations attached to an ancient book. They provided tools for thinking about the relationship between a divinatory result and the changing conditions in which an event might take place.

The excavated Haihun Hou Yizhan belongs to this story. Its sixty-four figures, associated with seasonal and calendrical indications rather than with the normal received line statements, show an Yi system being organized in a distinctly Han fashion. The book’s figures could be made to speak about when as well as what.

Enter the Forest of Changes

The Yilin is traditionally attributed to Jiao Yanshou 焦延壽, also known as Jiao Gong 焦贛, an influential figure in accounts of Western Han Yi learning. The surviving work is made up of short, often rhythmic pieces attached to pairs of hexagrams. Many verses are vivid: journeys, animals, households, rulers and omens appear in miniature scenes. For a reader who enjoys the imagery of the Zhouyi, this is a remarkable extension of the same pleasure.

Its architecture is beautifully simple to describe. Start with a root hexagram. Within its section, find a second hexagram. The verse at that intersection is a possible divinatory text. Repeat the arrangement for each of the sixty-four roots, and the resulting grid contains 4,096 places. Some verses recur; the surviving text has its own history of copying and variation.

But how did somebody arrive at the second hexagram? That question takes us into the history of the work’s actual use, and it is more interesting than choosing the first modern method we happen to know and projecting it backwards.

What was the Yilin originally for?

The traditional heading and prefaces present the Yilin as a book connected with divination. The texts themselves certainly lend themselves to that purpose. They often depict situations and point toward welcome or unwelcome results, much as the older Zhouyi does, but through a vastly expanded collection of verses.

The question of selection is less straightforward. The later textual tradition preserves the familiar idea of obtaining one hexagram and looking at the verse for its relation to a second. A Song-era preface associated with Huang Bosi 黃伯思 describes a common approach in which a cast hexagram is read against the hexagram to which it changes; with no moving lines, the original hexagram’s own verse may be used. That is important testimony about how people understood and used the book in the Song.

Other scholars have investigated a quite different procedure sometimes called 分卦直日, assigning hexagrams to days. A close study by Fujita Mamoru 藤田衛 (2021) compares the surviving bibliography, prefaces and discussions of practice and shows that several methods have been associated with the text. The day-assignment method is clearly discussed in later sources. It is worthwhile to keep the original question open while we examine the evidence: which procedure best explains what the Yilin was designed to do, and which procedures arose during its long reception?

Start with the matrix and a few verses, and the genius of the arrangement comes into view. Then the evidence from the prefaces and later discussions shows how readers turned that architecture into different ways of consulting the oracle.

Reading a verse

You might begin with a root hexagram and look at several verses in its section. Compare what remains constant and what changes as the second hexagram changes. Look for images, places, auspicious indications and repeated wording. This is a satisfying way to get acquainted with the text without committing immediately to one method of consultation.

A later diviner may use moving lines to identify the destination hexagram; another may have linked the choice to a calendar. In either case the Yilin adds a new body of divinatory language to the figures. It is a further answer to a question that has followed us throughout this guide: what can we do with the sixty-four hexagrams, besides read the traditional line statements?

The Han fascination with structure also produced a system that still underlies a widely used form of Chinese divination: the Eight Palaces associated with Jing Fang 京房. In the next chapter we will see how the hexagrams can be arranged into eight families and how that arrangement became essential to later Wenwang Gua practice.

Sources and further reading