What is the I Ching? The Book of Changes explained

Where the I Ching comes from

The I Ching (易經, Yì Jīng) is one of the oldest books in the world. Its core, the Zhouyi or “Changes of Zhou”, took shape in the Western Zhou dynasty, roughly three thousand years ago, as a manual for divination. Tradition credits the eight trigrams to the legendary sage Fu Xi, the hexagram texts to King Wen of Zhou, and the line texts to his son, the Duke of Zhou.

Over the following centuries a set of commentaries called the Ten Wings was added, traditionally attributed to Confucius. They turned the book from an oracle into a work of philosophy, and the I Ching became the first of the Confucian Five Classics. It shaped Chinese thought on change, timing and balance, and later fascinated Western readers from Leibniz, who saw binary numbers in its lines, to Carl Jung.

Yin and yang lines

Everything in the I Ching is built from two kinds of line. A solid line (⚊) is yang: firm, active, bright. A broken line (⚋) is yin: yielding, receptive, dark. Neither is good or bad. The book’s central idea is that situations are always moving between them.

The eight trigrams

Stack three lines and there are eight possible combinations. These are the trigrams (八卦, bāguà), each with a natural image and a quality.

The 64 hexagrams

Put one trigram on top of another and you get a hexagram of six lines. Eight times eight gives 64 hexagrams, each with a name, a judgment, an image and a text for every one of its six lines. The lower trigram is the inner situation and the upper trigram the outer one. Hexagram 11, Peace, puts Earth above Heaven, so the two meet and mix; hexagram 12, Standstill, puts Heaven above Earth, so they drift apart. The traditional King Wen order pairs them like this throughout the book. You can browse all 64 hexagrams, with a chart to find any hexagram from its two trigrams.

How to consult the I Ching

A reading builds a hexagram from the bottom line up, one line at a time. There are two classical methods.

The three-coin method

Toss three coins six times. Heads count 3, tails count 2, so each toss totals 6, 7, 8 or 9:

The yarrow stalk method

The older method divides 50 yarrow stalks through a slow sequence of counts for each line. It takes about twenty minutes and produces slightly different odds, shown in the table: old yang appears more often than old yin. Many people value it as a meditation in itself.

You can cast a hexagram with three coins here, with each toss shown as it lands.

Changing lines and the relating hexagram

Lines totaling 6 or 9 are “old”, and old lines are changing: they are about to turn into their opposite. They carry the most specific advice in a reading. Flip every changing line and you get a second figure, the relating hexagram, which shows where the situation is heading.

When several lines change, the Song dynasty scholar Zhu Xi set out the rules most readers still use:

• No changing lines: read the judgment of the hexagram.
• One: read that line’s text.
• Two: read both lines, with the upper one leading.
• Three: read the judgments of both hexagrams.
• Four: read the two unchanging lines of the relating hexagram, the lower one leading.
• Five: read the one unchanging line of the relating hexagram.
• Six: for hexagrams 1 and 2 read their special “all lines” text; otherwise read the relating hexagram’s judgment.

How to read an answer

The I Ching rarely says yes or no. It describes the nature of the moment and the conduct that fits it: when to advance and when to wait, when to speak and when to hold still. Read the judgment for the overall situation, the image for the attitude to take, and the changing lines for the specific turning point. Then ask what that advice looks like in your own circumstances.

Traditionally you ask once and live with the answer for a while. Hexagram 4 warns that asking the same question again and again muddies the oracle.

Frequently asked questions

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