Concerning Chu Hsi’s Rules of Interpretation

Chu Hsi (1130-1200), besides turning Neo-Confucianism into what would be the dominant school of Chinese philosophy for the next six centuries, in 1186 published I-hsüeh ch’i meng (Introduction to the Study of the Classic of Change).  He was a firm believer in the I Ching as a book of divination, and the I-hsüeh ch’i meng is a distillation of the then-current wisdom concerning the origin of the trigrams and hexagrams, the use of yarrow stalks to consult the oracle, and rules of interpreting the outcome based on the number of changing lines.  He describes his book as a collection of “old sayings,” and the examples of divination that he includes imply that the aforementioned rules had been in common use.

Two of the rules present problems of interpretation of their own.  Below is a discussion of these two rules, followed by a summary of the rules which takes all factors into consideration.  I am using the 2002 translation by Joseph A. Adler.


I.  The rule for three changing lines

The rule for interpreting an outcome with three changing lines makes reference to the arrangement of all possible hexagrams as illustrated in 32 charts which accompany the text:

When three lines change, the prognostication is the T’uan statement of the original hexagram and the resulting hexagram, and we use the original hexagram as chen and the resulting hexagram as hui.  In the first ten hexagrams [of this sort] we make chen the ruler; in the latter ten hexagrams we make hui the ruler.

(The T’uan statement is the main text of the hexagram; chen is the question, or present situation; and hui is the prognostication.)  This rule may cause some consternation to users of the I Ching, as it appears to require the availabililty of the rather voluminous charts to determine whether or not the resulting hexagram is one of the “first ten.”  However, a close examination of the charts reveals a simpler way to implement the rule.

According to Chu Hsi:

We now take the changes [combinations] of the sixty-four hexagrams and arrange them into thirty-two charts . . . .  To obtain the first [32] hexagrams we go from beginning to end and from top to bottom.  To obtain the last [32] hexagrams we go from the end to the beginning and from bottom to top.
[Below] are the thirty-two charts.  By reversing them we have sixty-four charts.  Each chart takes one hexagram as ruler and combines it with each of the sixty-four hexagrams, for a total of 4,096 hexagrams.  This agrees with the Chiao Kan’s I-lin (Grove of Changes).  But its rational principle is subtle and fine, and consequently there are aspects of it that have not been expressed by former scholars.  Those interested should examine it.

000001 000011 000111 001111 011111 111111
000010 100001 010001 001001 000101 110001 100011 010011 001011 111001 110011 100111 010111 101111
000100 100010 010010 001010 000110 110010 101001 100101 011001 010101 001101 111010 110101 101011 011011 110111
001000 100100 010100 001100 110100 101010 100110 011010 010110 001110 111100 110110 101101 011101 111011
010000 101000 011000 111000 101100 011100 101110 011110 111101
000000 100000 110000 111110
(the first of 32 charts)

Above is the chart for hexagrams one (Ch’ien) and two (K’un).  The charts all begin and end with different hexagrams, but they all follow this same pattern.  The twenty hexagrams with three moving lines occupy the middle six columns of the chart.  The first ten hexagrams of this sort (as described in the rule above) are shaded in the color of their original hexagram.  Can you see what they all have in common?  It holds true for each hexagram.  (Several of the 32 charts in my edition of the book actually have a misprint or two, which in this case are identifiable because they do not contain three moving lines and are thus out of place.)

I read Chu Hsi’s invitation to examine the charts as a literary wink to the reader, challenging him/her to figure it out for himself/herself.  If my understanding is correct, then the last part of the rule for three moving lines could be restated:  “If the first line is a changing line we make chen the ruler; otherwise we make hui the ruler.”


II.  The rule for all unchanging lines

Any hexagram may have all unchanging lines.  In that case we prognosticate on the basis of the original hexagram’s T’uan statement, taking the inner hexagram as chen [the question, or present situation] and the outer hexagram as hui [the prognostication].

What are these inner and outer hexagrams?  I am tempted to understand the inner hexagram to be the nuclear hexagram.  But Chu Hsi’s illustrative example clearly refers to lower and upper (though not strictly “inner” and “outer”) trigrams.  In the previous chapter of the book, hexagrams are similarly described as a combination of inner and outer trigrams.  And nuclear hexagrams are not referred to anywhere else in the book.  As the word here translated “hexagram” is gua, which actually refers to either figure, my guess is that these inner and outer figures are trigrams.  (Although this seems disappointing to me, as I would expect the results to include text of some sort.  I must be using the wrong side of my brain.)


III.  A summary of the rules

• If the hexagram has all unchanging lines, we prognosticate on the basis of the original hexagram’s T’uan statement, taking the inner trigram as chen (the question, or present situation) and the outer trigram as hui (the prognostication).

• When only one line changes, we take the statement of the original hexagram’s changing line as the prognostication.

• When two lines change, we take the statements of the two changing lines of the original hexagram as the prognostication, but we take the upper of the two as ruler.

• When three lines change, the prognostication is the T’uan statement of the original hexagram and the resulting hexagram, and we use the original hexagram as chen and the resulting hexagram as hui.  If the first line is a changing line we make chen the ruler; otherwise we make hui the ruler.

• When four lines change, we use the two unchanging lines in the resulting hexagram as the prognostication.  But we take the lower line as ruler.

• When five lines change, we use the unchanging line of the resulting hexagram as the prognostication.

• When six lines change, the prognostication is the T’uan statement of the resulting hexagram, except in the cases of Ch’ien and K’un (hexagrams one and two).  These have additional texts appended after their line texts, which are used as the prognostication.





Chu Hsi
Chu Hsi.  I-hsüeh ch’i meng (Introduction to the Study of the Classic of Change).  Translated by Joseph A. Adler.  Provo:  Global Scholarly Publications, 2002.