A technical primer8 short snapshots: what it is, how to use it, how to read casts, and where it has travelled.
You bring a question, cast six lines with coins, and the result points you to one of those 64 patterns. Each one describes a moment in a cycle: a beginning, a gathering, a standstill, a breakthrough. Reading it helps you step back from a situation and see its shape: what is building, what is fading, and whether this is a time to act or to wait.
The choices stay with you. For three thousand years, people have used it as a quiet mirror for the present, a way to see more clearly before deciding what to do.
Each pattern, called a hexagram, is a stack of six lines, broken or unbroken. Together the 64 hexagrams describe the ways a situation can unfold.
One cast gives one hexagram. It shows the main forces in play right now, and where you are in the cycle.
Some lines come up as changing. They show where things are already shifting, and point to the pattern that comes next.
易 yì means change or ease; 經 jīng means classic. Older sources call the core text the Zhou Yi, the Changes of Zhou.
This course follows the translation lineage of Richard Wilhelm (German, 1924) and Cary F. Baynes (English, 1950).
Tradition says King Wen of Zhou arranged the 64 hexagrams and wrote a short judgement for each while he was imprisoned. His son, the Duke of Zhou, is said to have added a text for each of the six lines.
Ten commentaries, called the Ten Wings, explain what the hexagrams mean and the philosophy behind them. Tradition credits Confucius; scholars date them to between about 400 and 100 BCE. They have been printed with the book ever since.
Bamboo strips from around 300 BCE, now in the Shanghai Museum, include an early copy of the text with different wording, written before the version we read today became fixed.
A copy written on silk was buried in a tomb in 168 BCE and found in 1973. It puts the hexagrams in a different order from the version we read today.
The Jesuit missionary Joachim Bouvet sends the philosopher Leibniz a chart of the hexagrams. Leibniz sees in it his own binary numbers, the 0s and 1s computers use today, and publishes his binary arithmetic in 1703.
Wilhelm’s German translation, made with the Chinese scholar Lao Naixuan, becomes the most widely read Western version of the book.
Norbert Wiener publishes Cybernetics, the science of feedback and self-regulating systems. Readers since have recognised the same idea in the I Ching: two states, yin and yang, constantly feeding back into each other to form one of 64 configurations.
Cary F. Baynes translates Wilhelm into English, with a foreword by Carl Jung linking the book to his idea of synchronicity, or meaningful coincidence. It is still the edition most English readers use.
The German doctor Martin Schönberger points out that the 64 hexagrams line up with the 64 codons of the genetic code, the three-letter “words” DNA is written in. His book appears in English in 1979 as The I Ching and the Genetic Code.
After the Cultural Revolution, study of the I Ching returns in China. Universities, publishers and the wider public take it up so widely that the period becomes known as Yijing fever.
Edward Shaughnessy publishes the first English translation of the Mawangdui silk version, so readers can compare the buried copy with the text handed down for two thousand years.
Tsinghua University publishes the Shifa, a divination manual written on bamboo around 2,300 years ago. It shows how casts were calculated and read long before the text took its final form.
In China and across East Asia the eight trigrams appear everywhere: on South Korea’s flag, on bagua mirrors hung above doors, in feng shui, and in choosing names and dates. Many people still consult the book before big decisions.
Practitioners around the world still cast with coins. The Metaphysics Agency has made more than 13,000 hand casts, each cast once and recorded exactly as it falls.
The I Ching wasn’t written by one person. It grew over three thousand years: an ancient core text, then layers of commentary, then translations into other languages. Tradition names a few authors, and manuscripts dug up in the last fifty years show earlier versions with different wording and a different order.
Most modern scholars see the traditional authors as legend, and read the book as built up in layers over several centuries.
The manuscripts and translations have their own cards in the Objects drawer.
All you need is three coins and a question. Hold the question in mind and throw the coins six times. Each throw gives you one line, and you build the hexagram from the bottom up.
How the text is used. Each hexagram has a judgement that describes the whole situation, an image, and a short text for each of its six lines. Read the judgement first, then the texts for your changing lines, then the second hexagram. Treat it as a description of the moment you are in, and look for where it fits your situation.
In this practice, each question is cast once, by hand, and treated as a clean reading: nothing carries over from earlier casts, and nothing is re-cast for a better answer. Readings work from the classical Zhouyi in the Wilhelm-Baynes translation, and read the pattern through the body as well as the mind.
→For detailed instructions, see How to Cast in the Hexagram Lookup
Traditionally the text is treated as a wise adviser, so you can also ask “What is the advice on X?”
With coins: 6 and 9 each come up 1 in 8; 7 and 8 each 3 in 8.
With yarrow stalks: 6 is 1 in 16, 7 is 5 in 16, 8 is 7 in 16, 9 is 3 in 16.
Changing and unchanging lines look the same when drawn. Mark a 6 with × and a 9 with ○ so you can find them later.
“All day long the superior man is creatively active. At nightfall his mind is still beset with cares. Danger. No blame.” Hexagram 1, line 3.
In plain words: hard work has brought you somewhere exposed. Stay alert and you will come to no harm.
AI is good at explaining the classical line texts, because centuries of commentary exist for each one. Working out the hexagram itself is where it goes wrong (see lesson 05).
Three coins. One side counts 3, the other 2.
Yarrow stalks, the older method.
There are 64 hexagrams, one for every way six solid or broken lines can be stacked. Each has a name, a short judgement, an image, and a text for each of its lines. Tap any hexagram above to see the question it asks; the 64 Hexagrams page holds the full reading for each.
The traditional order is credited to King Wen. The hexagrams come in pairs, and in 28 of the 32 pairs the second is simply the first turned upside down. You can try this in lesson 05.
The diagram Bouvet sent Leibniz in 1701, with Leibniz’s numerals.
A hexagram is read from the bottom up, but almost everything else we read runs from the top down. That makes it easy to read one the wrong way round, especially once it has been written out or typed. Flip it and you land on its partner: a different hexagram that can sound like a reasonable answer but describes something else. This is the mistake AI makes most often. Use the tool above to turn hexagrams over and see their partners.
Eight hexagrams look the same upside down: 1, 2, 27, 28, 29, 30, 61 and 62. Their partner is made by flipping every line from solid to broken, and broken to solid, instead.
Type in your six numbers from bottom to top, and the lookup shows your hexagram, which lines are changing, and the hexagram they lead to, with the classical text for each. It needs no account and stores nothing on a server: everything stays in your browser. It keeps a history of your casts that you can export, and a ready-made prompt if you want AI’s help interpreting.
Your hexagram, its changing lines and the hexagram they lead to are all shown together, so you can see the whole cast at once.
Every cast is saved in your browser and can be exported, so the lookup works like a notebook you can come back to.
Before building any software, every cast was made by hand, to understand the physical process first.
The coins, the surface and the way they were thrown were all examined, to see whether any of it changed the results.
The casts kept coming until there were enough to compare properly: more than 13,000.
Hand casts were compared with computer-generated ones, and that comparison shaped how the hexagram lookup was built.
I wrote many programs to cast the I Ching. Because I weigh my integrity in gold, I had to be sure there was no big difference between casting by hand and casting with a random number generator (random.org). So I threw the coins about 13,000 times between September 2025 and January 2026, and ran hundreds of simulations alongside.
I wanted to know whether the thing I was building was actually faithful to the thing I was trying to understand.
Even once a computer could generate the cast, AI kept getting the hexagram number wrong. Almost everything it has learned from is read left to right and top to bottom, while a hexagram is read from the bottom up. I tried various methods, including hard rules, and it still would not reliably produce the correct hexagram. So I built the lookup.
I was studying ancient cosmograms for mapping change and found the I Ching. At first I was sceptical, but seeing that I’m Chinese I figured it’s probably a good time to get familiar with it.
Let a simple, exact tool work out the hexagram. Let AI help with interpretation, where its knowledge of the commentaries is useful.
Dick consulted the I Ching while writing The Man in the High Castle and used its results to help determine the novel’s plot. The same mechanism enters the fiction itself: the characters consult the I Ching inside the alternate world of the book.
Cage kept a copy of the I Ching, three coins and a large chart of sound events beside him while composing. He used repeated coin consultations to generate hexagrams and let those results determine musical structures.
Jung wrote the foreword to the Wilhelm / Baynes English edition and treated the I Ching as an important case for thinking about meaningful coincidence, symbolism and synchronicity.
This is the extraordinary object: a diagram of the hexagrams sent by the Jesuit Joachim Bouvet to Leibniz. The Arabic numerals were added by Leibniz. The sheet connects the history of the I Ching to the history of European mathematics in a single physical artifact.
In her essay “A Non-Euclidean View of California as a Cold Place to Be,” Le Guin asked the I Ching to describe a yin utopia. It returned Hexagram 30, with the first line changing to Hexagram 56, the Wanderer. She records that the writing and revisions of the essay were considerably influenced by continuing to think about those texts.
Pink Floyd’s 1967 song Chapter 24 draws its lyrics from the Richard Wilhelm / Cary Baynes I Ching. The song is an unusually direct transformation: passages from the text become the words of a psychedelic rock track.
The I Ching describes the world as always changing between two forces, yin and yang. That simple idea sits close to modern thinking about systems and information, and it has drawn in mathematicians, psychologists, novelists and musicians. Scroll the cards above to meet a few of them.
