Hexagram 18 Gǔ (蠱): Work on What Has Been Spoiled, Meaning and Six Lines
The eighteenth hexagram of the I Ching: the Mountain above the Wind, repairing what has become worn. Judgement, six lines, moving lines and a careful reading of Work on What Has Been Spoiled.
Key points
| Number | 18 of 64 (King Wen sequence) |
|---|---|
| Chinese name | 蠱 (Gǔ) |
| Approximate pronunciation | goo |
| French name (tradition followed here) | Gu, le Travail sur ce qui est corrompu (Work on What Has Been Spoiled) |
| Lower trigram (inner) | Xun, Wind |
| Upper trigram (outer) | Gen, Mountain |
| Lines, bottom to top | yin / yang / yang / yin / yin / yang |
| Twin hexagram | No. 17, Sui, Following |
Hexagram 18: Gǔ (蠱), name and composition
Hexagram 18 is titled “Work on What Has Been Spoiled”. The character depicts worms in a vessel: something that has gone bad. In ancient China the word also designated a curse; the hexagram, however, is concerned with repairing what has deteriorated.
Hexagram 18 is written 蠱 (in simplified characters: 蛊) and transcribed Gǔ in pinyin; it is pronounced roughly “goo”. It is made of two trigrams stacked on top of each other: below, inside, Xun (Wind); above, outside, Gen (Mountain). The overall image is therefore the Mountain above the Wind.
The six lines, from bottom to top, are: yin (broken), yang (solid), yang (solid), yin (broken), yin (broken), yang (solid). In the King Wen sequence it forms a pair with hexagram 17 (Sui, Following), which is both its reverse (upside down) and its inverse (each line changes nature).
The judgement in brief
The judgement is favourable: great success, and it is advantageous to cross the great river. It adds a note on timing: three days before the start, three days after. Prepare before repairing, and keep watch afterwards.
General meaning
The Mountain lies above the Wind: the wind meets the rise of the land and stops there, and the air stagnates. It is the image of what has stiffened through neglect. The text speaks of an inheritance of faults: corruption is often the kind left behind by predecessors, evoked through the figures of father and mother. Repair requires recognising what has deteriorated, and acting with tact and without blame.
In practice, the hexagram speaks of renewal: a family, a business, a habit, a rule that has lost its meaning. The lines add nuance: daring to repair without hurting, tempering zeal, letting things be when nothing can be done, honouring those who did well, or withdrawing in service of a higher ideal.
The six lines, one by one
The lines are counted from bottom to top. Below, in our own words, is the image the ancient text attaches to each one; the last column gives the hexagram obtained if that line alone is moving.
| Line | Nature | Summarised image | If it is moving |
|---|---|---|---|
| 1 | yin (broken) | Repairing what a father left spoiled: if the child is worthy, the late father is not at fault; danger, then a good ending. | No. 26 (Da Chu) |
| 2 | yang (solid) | Repairing what a mother left spoiled: without excessive rigidity. | No. 52 (Gen) |
| 3 | yang (solid) | Repairing the father’s legacy: a little regret, no great fault. | No. 4 (Meng) |
| 4 | yin (broken) | Letting the father’s legacy slide: carrying on this way leads to distress. | No. 50 (Ding) |
| 5 | yin (broken) | Repairing the father’s legacy: it earns respect. | No. 57 (Xun) |
| 6 | yang (solid) | Not serving the princes: devoting oneself to a higher ideal. | No. 46 (Sheng) |
Moving lines
A moving line is a line that the casting marks as unstable: you read its own text, then it changes into its opposite, which gives a second hexagram, read as the direction the situation is taking. A moving yang line is called “nine”, a moving yin line “six”. Without a moving line, you keep to the general judgement.
For Gu, a moving line places your work of repair: acting with respect for those who came before, with flexibility, with a measure of acknowledged regret, without letting things slide, seeking respect, or withdrawing towards an ideal.
A modern reading, with care
Today, Gu is often read in relation to a family inheritance, an organisation to be put back in order, or a habit to undo. A careful reading sees in it an invitation to repair without looking for someone to blame: naming what has deteriorated, acting with tact, preparing before intervening. If the inheritance in question involves violence or painful grief, a health professional or a psychologist can support you.
Questions for reflection
- What has deteriorated in my situation, and since when?
- What can I repair without hurting anyone?
- Have I prepared the ground before acting?
- What in this inheritance deserves to be kept?
Mistakes to avoid
- Looking for someone to blame rather than a repair.
- Acting without preparation, although the judgement advises three days of preparation.
- Letting things slide in the hope they will sort themselves out, as in the fourth line.
- Reading the character as a curse: the hexagram speaks of upkeep and repair.
Names, translations and a reminder
The French name “Gu, le Travail sur ce qui est corrompu” follows one translation tradition among others. Other translations speak of Corruption, Poison, Decay or the Repair of What Has Spoiled; “Work on What Has Been Spoiled” conveys the idea of a repairing action. Compare two translations if you can.
A reminder: the I Ching is a book of wisdom and divination, consulted as a tool for reflection, never as a prediction; it does not replace medical, legal, financial or safety advice. This page summarises the text in our own words.
Frequently asked questions
What does hexagram 18 of the I Ching mean?
It is the hexagram of repair: what has been worn down through neglect or inheritance must be put back in order, with tact and preparation.
Why three days before and three days after?
The judgement invites you to prepare the action and to watch over its consequences. Commentators link these three days to the ancient cycle of ten days.
Does Gu deal with witchcraft?
In ancient China the character also designated a curse, but the hexagram speaks of repairing what has deteriorated, not of magic.
What are the trigrams of hexagram 18?
Xun (Wind) below, inside, and Gen (Mountain) above, outside.
What is the twin hexagram of number 18?
Number 17, Sui, Following. In the King Wen sequence, hexagrams come in pairs, the second being both its reverse (upside down) and its inverse (each line changes nature).
Also read
The meanings mentioned belong to tradition and symbolism. They are neither promises of results nor medical advice. Back to The 64 hexagrams of the Yi King.