Hexagram 18 蠱 Gǔ for Decision Questions 蠱 問決策

Hexagram 18 (蠱, Gǔ) is one of the 64 classical I Ching hexagrams. Wilhelm’s English translation renders the hexagram’s name as “Work on What Has Been Spoiled (Decay)”. This page describes how classical commentary reads this hexagram when received in answer to a decision question.

“Work on What Has Been Spoiled has supreme success. It furthers one to cross the great water. Before the starting point, three days. After the starting point, three days.”
— classical judgment text

“The wind blows low on the mountain: the image of Decay. Thus the noble person stirs up the people and strengthens their spirit.”
— classical image text

The hexagram’s general theme

Inherited rot — old systems and family patterns that were left to decay. The work is reform, not blame: cleanly fix what was left for you.

Classical keywords: repair, inherited problems, reform, cleaning up, ancestral patterns.

蠱 Gǔ read for decision questions

Classical I Ching commentary reads decision questions through the hexagram’s register of timing, alignment, and the relationship between proposed action and surrounding conditions. The hexagram describes the field of forces around the decision; classical doctrine reads whether the moment favours proceeding, waiting, reframing the question, or pivoting to a different option entirely.

The hexagram’s register does not have explicit decision-domain resonances in its modern interpretive keys, but applies to decision questions through its general theme described above.

Classical guidance for the hexagram: Three days before, three days after — prepare carefully, follow through carefully. The repair work is the path to supreme success.

Read against a decision question, this guidance describes the field of forces around the hexagram’s register of timing, alignment, and the relationship between proposed action and surrounding conditions. the hexagram describes the field of forces around the decision; classical doctrine reads whether the moment favours proceeding, waiting, reframing the question, or pivoting to a different option entirely.. The action the guidance suggests — or warns against — applies to the decision question being asked, with the chart-specific qualifications that consultation provides.

Configuration

• Hexagram: #18 蠱 (Gǔ), “Work on What Has Been Spoiled (Decay)”
• Question type: Decision (決策)
• Question domain: Binary choices, multi-option decisions, timing of action, whether-to-proceed questions
• Upper trigram: gen · Lower trigram: xun
• Hexagram lines (top to bottom): 100110 (1 = yang / solid, 0 = yin / broken)

Why a generic hexagram-for-decision interpretation falls short

This page describes what classical commentary reads when Hexagram 18 is received for a decision question — the hexagram’s general register applied to the decision domain. But a complete I Ching reading for a specific question requires the casting method (yarrow vs three-coin), identification of changing lines, the resulting secondary hexagram, and integration with the querent’s specific BaZi chart. Without those, the reading is reference-level — the broad register, not the chart-specific application. For chart-aware reading on a specific high-stakes decision, book a BaZi consultation. The four-pillar chart layered with the I Ching reading and the timing analysis produces decision-level diagnostic depth.

Hexagram 18 蠱 Gǔ read for a decision question is one input in a complete classical reading — not the whole answer. Classical I Ching practice layers four inputs together; the hexagram is only the second.

1. The casting method and quality of the question. Yarrow stalk vs three-coin vs other methods produce different statistical distributions of changing lines. The framing of the question itself shapes the answer — vague or compound questions return readings that classical commentary specifically warns against. A consultation handles both the casting and the question-framing as part of the reading.
2. The hexagram itself. What this page describes — the classical register of the hexagram and how it reads for the specific question type. Useful as reference; not sufficient on its own.
3. Changing lines and the secondary hexagram. Most I Ching readings produce one or more changing lines (动爻) which determine a secondary hexagram (之卦) representing how the situation evolves. The reading is the primary hexagram’s present register modulated by the changing lines and resolved by the secondary hexagram’s future register. Identifying which lines have changed and reading the secondary hexagram is the chart-casting skill that consultation provides.
4. The querent’s specific BaZi chart. Classical practice layers the I Ching reading with the querent’s four-pillar BaZi chart — the chart describes the querent’s position within the field of forces the hexagram describes. Two people receiving the same hexagram in answer to the same kind of question often need different responses based on their charts.

This page describes the second input — Hexagram 18 蠱’s register for decision questions. The reading is a useful starting reference. It is not a substitute for a chart-aware reading that layers in the other three. Master Sean Chan’s BaZi consultation reads all four layers against your specific question.

• Recognise the hexagram’s general register first. Inherited rot — old systems and family patterns that were left to decay. The work is reform, not blame: cleanly fix what was left for you.
• Read it through the decision-question lens. Classical I Ching commentary reads decision questions through the hexagram’s register of timing, alignment, and the relationship between proposed action and surrounding conditions. The hexagram describes the field of forces around the decision; classical doctrine reads whether the moment favours proceeding, waiting, reframing the question, or pivoting to a different option entirely.
• Note the classical guidance. Three days before, three days after — prepare carefully, follow through carefully. The repair work is the path to supreme success.
• Recognise that this is one input of four. A complete I Ching reading layers the casting method, the hexagram, the changing lines and secondary hexagram, and the querent’s BaZi chart together. Book a chart-aware consultation to combine all four layers.