Moving Lines

A line carries more than yin or yang

So far a line has had only two forms: yang or yin. During a casting, though, each line receives one of four identities.

Beyond yin and yang there is a second piece of information: whether the line is stable or in the middle of changing. A stable line is called young; a changing one is called old. That gives four identities: young yang, old yang, young yin, old yin.

Old yang and old yin together are the moving lines. They are usually marked on the diagram, because they determine which passage you read next.

Six, seven, eight and nine

The common casting method is to throw three coins once per line and convert heads and tails into a number. The number always falls between six and nine.

Six is old yin: a yin line in the primary hexagram, and a moving line. Seven is young yang: a yang line, not moving. Eight is young yin: a yin line, not moving. Nine is old yang: a yang line, and a moving line.

A useful handle: odd numbers are yang and even numbers are yin; the outer two, six and nine, move, while the inner two, seven and eight, do not. The casting tab in this app uses exactly this six-to-nine scheme.

It also explains the convention from the earlier lesson: a yang line is written as "nine" and a yin line as "six" because these four numbers are where the names come from.

How many lines can move

Each of the six lines is determined on its own, so the number of moving lines can be anything from zero to six.

Zero moving lines means every line came out as a seven or an eight and the whole hexagram is stable. Six moving lines means every line came out as a six or a nine and the whole hexagram is in motion. Anywhere from one to five is the more usual case.

There is no rule that at least one line must move. Zero moving lines is a normal outcome, not a failure, and nothing needs to be thrown again.

What the mark actually means

Worth stating plainly: a moving line is a mark produced by the casting procedure. It says "apply the change rule to this line". It is not a judgement about the situation and it does not indicate that something will happen anywhere.

At the level of reading, its use is very concrete: it decides which passage you read next, and whether a second hexagram is produced at all. Those two topics are lesson six and the next lesson respectively.

Try it yourself

This lesson has a hands-on exercise. It is built into the Traditional Chinese lesson page, where you can try it straight away: open the interactive exercise.

How six, seven, eight and nine are counted

When casting one line with three coins, each coin has only two outcomes. The traditional method counts heads as 3 and tails as 2 (some schools count the other way round, but as long as the whole system is consistent the distribution of results is the same). Adding the three coins gives one of four numbers: 6, 7, 8 or 9.

Odd numbers are yang and even numbers are yin: 7 and 9 are both yang lines, 6 and 8 both yin lines. The difference is whether they change: 7 is an unchanging yang and 8 an unchanging yin, and these are called static lines; 9 is a yang that changes and 6 is a yin that changes, and these are the moving lines.

So a “moving line” is not another kind of symbol but a marker. When a yang line is recorded as a 9 it is still drawn as ⚊, with just a mark beside it showing that this line will flip later. Casting each of the six lines once gives six results that together make one whole hexagram, and tell you which lines in it are moving.

The four numbers do not appear with equal probability: 7 and 8 are more common than 9 and 6, so in a casting most lines are static and usually only a few lines move. That is simply the result of the method, not something anyone arranged.

More moving lines does not mean bigger change

The number of moving lines can be anything from zero to six. With all six static, no line is going to change; with all six moving, the whole hexagram flips. Both can happen, and no number is the “standard” answer.

A common misunderstanding is to read the number of moving lines as the seriousness of a situation, as if more moving lines meant more drama. In fact a moving line only marks which positions are turning, not by how much. What really affects the reading is which position the moving line is in, and which hexagram it turns into once flipped.

What the number of moving lines does change is the method of reading. With a single moving line, tradition mostly puts the emphasis on that line’s statement; with many, or all, moving lines, the line statements start to conflict and the emphasis usually shifts to the hexagram it turns into. Lesson 5 turns to that hexagram, called the “resulting hexagram”.

The three places beginners most often get stuck

Thinking a moving line is already in its changed form. It is not. A moving line marks “not yet changed, but about to change”, and in the original hexagram it is still its original yin or yang. The changed form belongs to another hexagram.

Choosing for yourself which line should move. Moving lines are the result of the casting: which line gets a six, seven, eight or nine is decided by that throw, not chosen by the reader.

Seeing zero moving lines and thinking the casting failed. All six lines being static is a normal result. It only means that this time no line is going to change, and you simply read the judgment of the original hexagram.

Quick Quiz