Changing lines in the I Ching: which text to read, and why

A reading rarely gives you a plain hexagram. Most casts contain one or more changing lines (動爻, dongyao), and knowing what to do with them is the difference between a muddled answer and a clear one. This guide explains what a changing line is, how it produces a second hexagram, and the traditional rules for which text to read when several lines move.

Old and young lines

Each line of a cast comes out as one of four values. With three coins, heads count 3 and tails 2:

• 6 — old yin (three tails): a broken line that is about to change into a solid one. Marked ×.
• 7 — young yang: a stable solid line.
• 8 — young yin: a stable broken line.
• 9 — old yang (three heads): a solid line that is about to change into a broken one. Marked ○.

The six values, bottom to top, form the primary hexagram (本卦, bengua). Flip every old line into its opposite and you get the changed hexagram (之卦, zhigua, literally "the hexagram it goes to"). The old lines are "ripe": the tradition reads them as the places where the situation is actively turning, and their line texts as the most specific part of the answer.

Why old lines carry the message

A line text (爻辭) describes what happens at one position of a situation. A stable line is background; a changing line is the event. That is why the convention is to read the Judgment of the primary hexagram for the overall picture, the changing line for the pivot, and the changed hexagram for where things tend afterward. The changed hexagram is not a second, independent answer — it is the direction of travel.

Our reading room shows this directly: on every hexagram page, each of the six lines links to the hexagram it would produce if it alone changed. For Hexagram 24, Fu, the first line moving gives Hexagram 2, Kun; the fourth line moving gives Hexagram 51, Zhen.

The rules for several changing lines

The Zhou text itself gives no rule; what follows is the convention set down by Zhu Xi (朱熹) in the Song dynasty, repeated by most later manuals and by Wilhelm. Count the moving lines:

• 0 moving lines — read the Judgment (and Image) of the primary hexagram. Exception: if all six lines are old in Hexagram 1 or 2, read the special text 用九 / 用六 ("when all the lines are nines / sixes").
• 1 moving line — read that line's text. Use the primary Judgment for context and the changed hexagram for the outcome.
• 2 moving lines — read both line texts; the upper one carries more weight.
• 3 moving lines — read the Judgment of the primary hexagram and of the changed hexagram; the primary describes the start, the changed the end.
• 4 moving lines — read the two lines that are not moving, in the changed hexagram; the lower of the two governs.
• 5 moving lines — read the single line that is not moving, in the changed hexagram.
• 6 moving lines — read the Judgment of the changed hexagram (for 1 and 2, the 用九 / 用六 text instead).

The logic: with few moving lines, the primary hexagram is still the situation and the movement is the news; with many, the situation has essentially become the changed hexagram, and the unmoving lines are what remains of the old.

Other schools exist. Some readers always use only the lowest moving line; some read every moving line and weigh them; Six Lines (六爻) practitioners, who work with a hexagram's "six relatives" rather than its text, treat moving lines differently again. If you adopt one rule, use it consistently — the value of a rule is that it stops you shopping for the verdict you prefer.

A worked example

Suppose a cast gives, bottom to top: 7, 8, 9, 8, 8, 7. That is solid, broken, solid, broken, broken, solid — ☳ Zhen below, ☶ Gen above: Hexagram 27, Yi (Nourishment), with one old line in the third place.

1. Read the Judgment of Yi: correct nourishment brings good fortune; look at what is being nourished and how you seek your own sustenance.
2. The third line (六三 in the standard figure, here changing) is the pivot: its text warns against nourishment pursued in the wrong way — "acting contrary to what is proper; perseverance brings misfortune."
3. Change line 3 and you have solid, broken, broken, broken, broken, solid — ☶ Gen over ☷ Kun: Hexagram 23, Bo, Splitting Apart: the direction if the warning is ignored.

The answer is specific and sober: the matter at hand is about sustenance, the current approach is the wrong one, and continuing erodes the situation.

A note on "no changing lines"

A hexagram without changing lines is not a weak answer. It says the situation is settled for now; the Judgment and especially the Image — "the superior person, in accordance with this, …" — tell you the conduct that suits it. Many experienced readers prefer such casts: the oracle has nothing to add, and the whole picture stands.