Home·How to cast

How to consult the Book of Changes

The classical coin method: how to frame a question, how to throw, how to build the hexagram and what to do with changing lines.

Cast now All 64 hexagrams

In brief: six throws

Take three identical coins.
Tails counts 3, heads counts 2. Throw all three and add them up.
You get 6, 7, 8 or 9 — that is one line of the hexagram.
Repeat six times, writing the lines from the bottom up.
Six lines make a hexagram — find its number and read it.

How to frame the question

This is the most underrated part. The Book of Changes answers badly to questions like «will I get this job» and well to questions like «what is the state of this matter and how should I act in it».

The difference is not politeness but structure. A hexagram describes not an event but a situation in motion: the arrangement of forces, the direction in which things are shifting, and the fitting way to act. A yes-or-no question simply has no counterpart in that language.

Write the question down. Half the vagueness disappears while you phrase it.
One question at a time.
Do not ask again. Repeating the same question hoping for a different answer destroys the procedure: you are no longer asking, you are shopping.
Ask about what is yours to do.

Why coins rather than yarrow

The oldest method is the sorting of fifty yarrow stalks. It takes about twenty minutes per line and gives probabilities of 1:5:7:3 for 6, 7, 8 and 9. Coins appeared later, around the Tang, and give 1:3:3:1.

On this site the coins are thrown by the browser’s cryptographic random number generator, with the same 1:3:3:1 distribution as real coins. Neither the question nor the time nor anything else affects the result — which is exactly what tradition demanded of the yarrow. More on the method page.

How the lines are counted

Sum	Name	Line	Changes
6	old yin	broken	yes, into solid
7	young yang	solid	no
8	young yin	broken	no
9	old yang	solid	yes, into broken

Why from the bottom up

A hexagram is read as a process in time: the bottom line is the beginning of the situation, the top its outcome. Hence the position names, and hence the fact that the same line means different things in different places.

Changing lines and the second hexagram

The first hexagram — the situation as it stands.
The texts of the changing lines — the most concrete part of the answer. If there are none, the situation is stable.
The second hexagram — not what will happen, but the direction in which things move if nothing is altered.

Cast the coins The eight trigrams