About three years ago I dreamt that I was wading through a subterranean waterway. The bed of the stream in this tunnel comprised pebbles and smooth boulders. Then -- suddenly and horrifically -- one of the boulders turned out to be the shell of a huge, spider-like crab...I used to kick my wife and lash out, trying to fight them off. It was as fierce and terrible as that.
The dream kept on for some time, on average about once a fortnight -- and his wife would regularly find herself on the floor.
After five months, it was discovered that Geoffrey had cancer of the colon. The interpretation seems very simple and clear. As in a virtual reality experience, Geoffrey was walking along his own colon and witnessed the events that had been occurring within him. The large boulders seem to be an image of the lining cells of the large bowel and it is usually one of those cells that fight them off.... The seriousness of the illness is translated into the terror Geoffrey feels...
The Hidden Power of Dreams( page 72) by Dr. Robin Roynston
How is it that a dream can represent an internal process so vividly and strongly? One can argue that there are alternate meanings and interpretations; it seems to me that representation is so precise, and so emotionally and physiologically relevant, that it is hard to argue for other interpretations. The repetitiveness of the dream also speaks to the urgency the unconscious body/mind expresses about the situation.
From an evolutionary point of view, this kind of representation makes sense. In the same way we are evolved to deal with external, we also have evolved to deal with internal threats. It would make sense that within the system is a kind of hologram of the whole system, a way to represent which parts of the organism are under threat. Words are a fairly recent development; it is not as if the evolved system can say in words, "Hey, you have cancer of the bowels." However, that information can be expressed in pictures, metaphors, symbols.