Changing lines.
Short answer. A changing line is a line cast as 6 (old yin) or 9 (old yang). It flips into its opposite and produces the relating hexagram. One moving line is read directly. With several, the classic gives no single rule; this edition follows Zhu Xi: two lines are read together with the upper leading; three are read from both judgments; four from the two unmoved lines of the relating hexagram; five from its one unmoved line; six from Qian's “using nines”, Kun's “using sixes”, or otherwise the relating judgment.
What a changing line is
Each of the six lines is cast as 6, 7, 8, or 9, counting from the bottom. 7 is young yang (solid) and 8 is young yin (broken): they stay as they are. 6 is old yin and 9 is old yang. These are the moving lines, and they turn into their opposite.
Flip every 6 and every 9 and you have the relating hexagram (also called the transformed or changed hexagram). The hexagram you cast is the primary hexagram. The primary describes the situation as it stands; the relating hexagram describes where it is tending.
The rule at a glance
Count how many lines came out 6 or 9, then use the matching row. This is the scheme in Zhu Xi's Yixue Qimeng (易學啟蒙, 12th century), chapter “Examining changes and prognostication”.
| Moving lines | What to read | Main text |
|---|---|---|
| 0 | The primary hexagram's judgment | — |
| 1 | That one line, in the primary hexagram | — |
| 2 | Both moving lines, in the primary hexagram | The upper of the two |
| 3 | The judgments of both hexagrams | The primary's if line 1 moved; otherwise the relating one's |
| 4 | The two lines that did not move, in the relating hexagram | The lower of the two |
| 5 | The one line that did not move, in the relating hexagram | — |
| 6 | Qian: “using nines”; Kun: “using sixes”; any other hexagram: the relating hexagram's judgment | — |
Two moving lines
Read both moving lines, and let the upper one carry the weight. For example, hexagram 26 Dà Xù changing to 37 Jiā Rén with lines 2 and 5 moving: read both, with line 5 as the main text and line 2 as context.
Zhu Xi notes that the classic says nothing explicit about this case; the two-line rule is his inference from the others. That is worth knowing before treating it as timeless.
Three moving lines
Put the line texts aside and read the two judgments, primary and relating. In practice, the primary judgment leads if the first (bottom) line moved; if it did not, the relating judgment leads.
For example, hexagram 3 Zhūn changing to 16 Yù with lines 1, 4, and 5 moving: line 1 moved, so the primary judgment leads and the relating judgment follows.
Four and five moving lines
With four lines moving, read the two lines that did not move, in the relating hexagram, with the lower one as the main text. With five moving, read the one line that did not move, again in the relating hexagram.
This is the part later readers objected to most: the line texts were written for 6s and 9s, so reading unmoved 7s and 8s can feel like reading a text that was not addressed to them. Zhu Xi nevertheless includes it, and we follow him.
All six lines moving
If every line is a 9, the cast is hexagram 1 Qián; read its extra text, “using nines” (用九). If every line is a 6, the cast is hexagram 2 Kūn; read “using sixes” (用六). For any other all-moving cast, read the relating hexagram's judgment.
Why there is no single rule
The Zhouyi itself does not set out a procedure for multiple moving lines. The rules above are a later convention, and other readers proposed different ones. Huang Zongxi (1610–1695), for instance, argued that with one moving line you should also read the matching line of the relating hexagram, and that unmoved lines have no text to give at all. Others read every moving line in order, treating the first as the beginning and the later ones as stages.
This site follows Zhu Xi because his scheme is explicit, case-by-case, and widely used. It is a choice, not a claim that every tradition agrees.
Common mistakes
- Treating 6 and 9 as ordinary lines. They are the moving lines; if you ignore that, there is no relating hexagram.
- Reading every moving line equally. With two or more, the rule says which text leads.
- “The uppermost line always wins.” That is the two-line rule only. It does not apply to three, four, five, or six moving lines.
- Forgetting the relating hexagram. The primary is where you are; the relating is where the situation is tending.
- Treating the rule as a prediction. It selects which text to read. It does not tell you what will happen.
How this site applies it
Every reading on I Ching Notes is composed from the primary hexagram, its moving lines, and the relating hexagram, with each section citing a passage_id. The multiple-line rule above is implemented in the reading engine. You can check the method on the method page, the editions on the sources page, or cast a hexagram and see the rule in context.
Questions
Do I read every changing line?
No. With one moving line, read that line. With two, read both but let the upper lead. With three, read the judgments rather than the line texts. With four or five, read the unmoved lines of the relating hexagram.
What if no lines move?
Read the primary hexagram's judgment as the whole answer. There is no relating hexagram, because nothing changes.
Is there one correct rule?
No. The classic does not specify one. This edition follows Zhu Xi's Yixue Qimeng; other traditions read these cases differently, and the method page says so.
Sources
Zhu Xi, Yixue Qimeng, chapter “Examining changes and prognostication” (考變占第四), as printed in the 1715 Yuzuan Zhouyi Zhezhong, juan 20: Wikisource transcription.
Huang Zongxi, Yixue Xiangshu Lun, juan 2, “Methods of divination” (占法): Wikisource transcription.
For how this site handles editions and translation, see Sources & editorial method.
Last reviewed: 19 October 2026 · I Ching Notes