I Ching guide

The I Ching (Yijing, the Book of Changes) is a Chinese classic more than two and a half thousand years old. Its core is 64 figures called hexagrams, each made of six lines that are solid (yang) or broken (yin), with a short judgment for the whole figure and a statement for each line. Later commentaries, traditionally credited to Confucius and his school, were added around it. It has been read as a manual of divination, a book of moral philosophy and a model of how situations change; this guide does not ask you to take any one of those views.

Lines and changing lines

A hexagram is cast one line at a time, from the bottom up. Each line gets one of four values:

• 7, young yang: solid, at rest.
• 8, young yin: broken, at rest.
• 9, old yang: solid and changing. Marked ○.
• 6, old yin: broken and changing. Marked ×.

The six lines give the first hexagram. If any line is changing, each changing line turns into its opposite, giving a second hexagram (often called the relating or resulting hexagram). The lower three lines and the upper three lines are each one of eight trigrams.

Casting methods and their odds

The two traditional methods do not give the same odds, and Scryway keeps each method’s own probabilities:

Both give solid and broken lines equally often, but with yarrow stalks a changing yang line is three times as likely as a changing yin line; with coins they are equally likely.

• Virtual three coins simulates tossing three coins per line, using your device’s cryptographic random generator. Each toss is shown.
• Virtual yarrow stalks simulates the odds of the yarrow-stalk procedure (1 : 5 : 7 : 3), not the counting itself.
• Physical cast guides you to record a cast made with your own coins, stalks or another method, line by line.

Casting by hand

Three coins

Toss three coins together. One side counts 3 and the other 2; add them to get 6, 7, 8 or 9. A common modern convention counts heads as 3. Others count the inscribed side of a Chinese coin as yin (2); choose one convention and keep to it. Toss six times and record the lines from the bottom up.

Yarrow stalks

The traditional method uses 50 stalks. One is set aside for the whole cast. For each line, with the remaining 49:

1. Divide the stalks at random into two heaps. Take one stalk from the right heap and hold it between the fingers of the left hand.
2. Count the left heap off in fours until four or fewer remain; hold the remainder. Do the same with the right heap.
3. The held stalks total 5 or 9. Set them aside.
4. Repeat steps 1–3 twice with the stalks left in the heaps. These second and third counts give 4 or 8.
5. Score each count: a small count (5, or 4) is 3; a large count (9, or 8) is 2. The three scores add up to 6, 7, 8 or 9.

It takes several minutes per line, which many practitioners value as part of the practice.

Reading conventions

Traditions differ on which texts to read when lines change. Scryway offers two and lets you switch between them on any cast; neither is presented as the authoritative one.

• Every changing line: A common modern practice: read the judgment of the first hexagram, the text of every changing line, then the judgment of the hexagram it changes into.
• Zhu Xi's rules: A traditional rule set attributed to the 12th-century scholar Zhu Xi (in his Yixue Qimeng), which picks particular texts by how many lines change. Summarised here as it is commonly taught; later scholars apply it differently.

Zhu Xi’s rules, as usually summarised, by the number of changing lines:

• None: the judgment of the hexagram.
• One: that line.
• Two: both lines, the upper one principal.
• Three: the judgments of both hexagrams, the first principal.
• Four: the two unchanged lines, read in the second hexagram, the lower one principal.
• Five: the one unchanged line, read in the second hexagram.
• Six: for hexagrams 1 and 2, their extra text for all lines changing; otherwise the judgment of the second hexagram.

The text used here

Judgments, line statements and the “Great Symbolism” image for each hexagram are quoted from James Legge (trans.), The Yi King, Sacred Books of the East vol. XVI, Clarendon Press, Oxford, 1882. Public domain. Legge’s English is Victorian and literal; words he added to make the Chinese read as English are in parentheses, and his romanised names (Khien, Khwan…) predate pinyin. Interpretations differ between translators, and Legge’s is one reading among many.

Each hexagram also has a one-line Scryway summary. These are modern commentary written for this site, labelled as such, and are not part of the classic text. Saved casts keep a copy of the text they were read with. Sources are listed on Sources and rights; transcriptions: hexagrams 1-32; hexagrams 33-64.

The eight trigrams

Images, qualities and family roles from the Shuo Gua (“Discussion of the Trigrams”), directions in the King Wen arrangement.