Gu :: Contamination
Crossing the great river: Before jia1 three days: after jia three days
Gu has a many faceted meaning. Gu refers to a curse or the negative influence (curse) of an unsettled ancestral spirit (ghost) and its calling out for resolu-tion. The traditional resolution includes divination and an exorcistic ritual on an astrologically auspicious day.2
Gu3 also refers to offending one's ancestors by mistakenly placing inappropriate, contaminated or rotten food offerings on an ancestral altar.
In the course of normal events "old debts" of the past come due. Each line describes different situations that are curable or incurable.
In the Zhou world, children were ultimately responsible for the conduct (errors and debts) of their parents (ancestors). Gu indicates that life is a continuous flow, not just an individual personal experience. Success is not simply a matter of personal control. Unseen environmental forces do affect us.
The ancestral cause described in Gu is an interfering ghost or a genetically inherited illness. For modern people, this hexagram denotes a difficult situation whose cause is unknown. We seem blocked or ill for no reason. Such rational thinking gives the situation a sense of injustice.
In some cases, Gu can be cleared by decisive action or medical treatment. In removing contamination, however, thoroughness is of utmost importance.
In some cases (top line statement), the debt is too heavy and all is lost.