A moving line is a line that is in the middle of changing. You get one when a line comes up as 6 or 9 among the line values:
- 6, old yin: a yin line turning into yang.
- 9, old yang: a yang line turning into yin.
The idea is simple. When a force reaches its extreme, it turns over. The deepest point of winter already points toward spring.
Why it matters
Moving lines are the most personal part of a reading. The whole hexagram describes the general situation. The moving lines show where the motion is, which part of that situation is touching you right now. That's why, when there are moving lines, you read their line text as well as the text of the hexagram.
And if you flip each moving line into its opposite, you get a second hexagram, the relating hexagram, which shows where the situation is heading.
An example
You cast Activity and the first line comes up as a 9. You read that line's text, which speaks of a dragon still hidden: it isn't time to act. Then you change that line to yin and get Lack of Firmness, which shows the direction things are taking.
How many can appear
Anywhere from none to six. There are traditional rules for reading each case, including Zhu Xi's; you'll find them in Moving Lines. If none appear, every line is a stable line and the hexagram is read on its own.