Changeable Lines, Zhi Gua, and Fan Yao

Modern convention refers to the lines of the I Ching numerically, in the form of 14:5, meaning hexagram 14, line 5.  According to The Book of Changes (Zhouyi) by Richard Rutt, traditional Chinese texts use a different convention, referring to a line as the one which changes its hexagram to another.  Line 5 changes hexagram 14 (Ta Yu) to hexagram 1 (Ch’ien); this line is thus referred to as Ta Yu zhi Ch’ien, meaning Ta Yu’s Ch’ien, or Ta Yu changing to Ch’ien.

The changed hexagram (zhi gua) may be used to illuminate the meaning of the specified line in the original hexagram.  This is illustrated by Hellmut Wilhelm in The Hexagrams Ch’ien and K’un.  Bradford Hatcher has gone a step further, referring to the corresponding line in the changed hexagram as the fan yao, meaning the “line in reverse” or “line coming back.”  I have included the reversed fan yao as they are part of “the Principle of Analogy and Correspondence” described by Wei Tat in An Exposition of the I-Ching or Book of Changes.  The pang tong yao complete the “foursome” of hexagram, reversed hexagram, changed hexagram, and reversed changed hexagram.

These hexagram and line relationships are not generally considered to be part of the response from the oracle.  They may be best understood as a potential source of deeper understanding of the original text.  I have written the script below so that each line in each hexagram may be studied in relation to its changed hexagram and fan yao.  Grouped like this, they form the “first families” described by Larry Schoenholtz in New Directions in the I Ching.  The fan yao are included in The Virtual Yarrow Stalks I Ching accompanying the steps of change, or simply as the fan yao if only one line is changing.


A study of the I-Ching is of necessity a study of symbols—of hexagrams, trigrams, and lines.  The meaning of one hexagram, or of one line, is often clarified and confirmed by a simultaneous examination of other related hexagrams or lines.

. . .

The main purpose is the detection of corresponding percepts, concepts, and ideas in the texts of the two or more interrelated hexagrams, and the synthesizing of them into more elaborate ideas or ideals.

—Wei Tat, An Exposition of the I-Ching or Book of Changes