After reading the link provided by John to Julian Jaynes' website, I would like to discuss his theory about the bicameral mind.
I think there may be some value to this, because all three of us (John, woodrabbit and me) have experienced being in the shamanic state, and thus have a practical experience of what Jaynes (I'm assuming) only knew about in theory.
Anyway, just to clarify our terms, this is from Wiki:
In psychology, bicameralism is a controversial hypothesis which argues that the human brain once assumed a state known as a bicameral mind in which cognitive functions are divided between one part of the brain which appears to be "speaking," and a second part which listens and obeys.
The term was coined by psychologist Julian Jaynes, who presented the idea in the 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind, wherein he made the case that the bicameral mentality was the normal state of the human mind everywhere as recently as 3000 years ago. He used governmental bicameralism metaphorically to describe this state, where the stored up experience of the right hemisphere was transmitted to the left hemisphere via auditory hallucinations.
This mental model was replaced by the conscious mode of thought, which Jaynes argues is based on metaphorical language. The idea that language is necessary for subjective consciousness or higher forms of thought has been gaining in acceptance in recent years, with proponents such as Daniel Dennett, William Calvin, Merlin Donald, John Limber, Howard Margolis, and Jose Luis Bermudez.
Basically, I think what he's saying is that shamanism stems from a time when man's mind was formed differently. He calls it the 'bicameral mind' because it is about the right and left lobes interacting with one another in a way that they no longer do, and haven't since the invention of language. He believes that the 'spirits' or 'gods' who talked to the shamans were just an aspect of their own personalities (not consciousness, because Jaynes believes that human consciousness only began to exist when language began).
I've been wondering about this, and here's a couple of early thoughts on it, to throw into the ring.
First of all, I find it hard to believe that consciousness is dependent on language, as I have been beyond language in my shamanic experiences and I am definitely conscious at the time - I just don't know who I am. Or rather, I know who I am but it definitely isn't the Ishtar/Gill person who I spend most of my time with. So 'self awareness' could be an issue - but not consciousness, imho.
Secondly, the spirits/gods sometimes tell shamans what's going to happen in the future. So that raises the question, how would that be possible if it was just one part of the shaman's brain talking to the other part?
Just some food for thought there.
Just for a start, consider "consciousness" vs. "self consciousness".
Consciousness recognizes a flock of geese rising from the valley as accurately, and actually way more accurately, than the self conscious observation that "the geese are flying out of the valley".
Consider the difference between the Panel of the Horses in the Chauvet Cave and my statement to you that "they put the three mares into the pasture in front of my house last week".
Language is the excrement of self-consciousness.
It seeks to safely codify the future from past "experience".
This is vastly different from the cognitive harmony of, for example, "the dreamtime", in which the future is irrelevant because of complete synthesis with the present and the past.
By the way, this does not mean that those people were unaware of the future. Rather, their harmony with "all that is" allowed them to clearly see and adapt to the future instead of using the broken self-conscious crutch of what happened in the past to mend the putative future with "history".
I'm not stating this as well as I would like.
My point is,
Consciousness is dynamic. Past, present and future are simultaneous in any event.
Self-Consciousness is static. Past, present and furure are separate events.
"Man is a marvellous curiosity. When he is at his very, very best he is sort of a low-grade nickel-plated angel; at his worst he is unspeakable, unimaginable; and first and last and all the time he is a sarcasm."