Decay
Hexagram 18 · Mountain over Wind
Published July 8, 2026 · By Oriens
元亨，利涉大川。先甲三日，後甲三日。
Decay has supreme success. It furthers one to cross the great water. Before the starting point, three days. After the starting point, three days.
— I Ching, Hexagram 18 (蠱), 元亨，利涉大川。先甲三日，後甲三日。
Decay has supreme success. It furthers one to cross the great water. Before the starting point, three days. After the starting point, three days.
Decay is not the end. It is the beginning of renewal. The wind erodes the mountain, but the mountain's substance feeds the valley below. What has rotted must be cleared before what is new can grow. Three days before, three days after — the work of restoration requires looking backward and forward. The superior person does not despair at decay but stirs the people and strengthens their spirit.
Hexagram 18, Gu (Decay), presents a striking image: wind blowing low on the mountain, eroding what was once solid. The Chinese character gu originally referred to a poisonous insect or a curse — something that festers and corrupts. But the judgment is remarkably optimistic: supreme success. The work of addressing decay, though difficult, is profoundly meaningful. The reference to three days before and three days after suggests careful preparation and follow-through. The I Ching describes the present moment with such precision that the next natural movement becomes visible. Understanding the pattern you are in is the first step toward wise action.