Great question. There is really so much more research that needs to be done as far investigating further evidence for, or possible exceptions to, Jaynes's dating of consciousness. Having observed modern society for many years with this question in the back of my mind, I've come to favor the more gradual transition, with different features of consciousness coming online (so to speak), at different times and to varying degrees. The development of consciousness would also likely vary from one individual to the next, just as it does (perhaps to a lesser degree) today. This would make a great research project for someone with the time available, perhaps a student looking for a topic related to psychological anthropology, etc.
Jaynes's theory makes a number of other predictions beyond just the dating of consciousness, and at the time Jaynes published his book it was not known how these predictions would be born out (although there was some suggestive evidence). I say this because much of what passes for "theories" of consciousness today are really no more than wild speculations with no predictions or testable hypotheses whatsoever.
I'll list a few of the predictions here, and perhaps others can add to the list. Had any of these been contradicted, it would have called into question at least some aspect of the theory. The fact that so many of the theory's predictions have to a large degree been confirmed over the past three decades adds to it's validity, and I think this is a point that is not often raised in discussions of the theory.
1. Jaynes's neurological model for the bicameral mind predicts that auditory hallucinations would be generated by the language areas in the right temporal lobe and be "heard" or processed by the left. This prediction has been now been verified as accurate by numerous studies. So at least as to Jaynes's fourth hypothesis, the case is now closed: Jaynes was not only correct but decades ahead of his time.
2. Jaynes's theory predicts that hallucinations in the normal population should be more common than was previously known. This has also now been confirmed over the past three decades in literally hundreds of studies.
3. Jaynes's theory predicts that hallucinations should be more common in children than was previously known. This has also now been confirmed, with recent estimates suggesting that up to a third or more of all children "hear voices" (termed imaginary companions). Adding additional support for Jaynes's theory, researchers have identified a "conscience-related" variety of imaginary companion concerned with directing the child's behavior and telling right from wrong.
4. Jaynes's theory predicts that consciousness, as Jaynes defines it, is based on language and should therefore be absent in pre-linguistic children and others who don't acquire language. This has been demonstrated in recent studies of the development of consciousness in children as well as the study of individuals who for various reasons experience delayed language acquisition.
5. Hallucinations and other vestiges of bicamerality should be seen in pre-literate societies. A number of works describe just this fact in tribes worldwide that were studied in the late nineteenth and early twentieth centuries. More recent studies of recently contacted tribes are adding further evidence.
6. Jaynes's theory predicts that hallucinations should direct or otherwise be related to behavior. This has since been confirmed in studies of "command hallucinations" in patients labeled schizophrenic. Hallucinations commenting on or directing behavior have now also been noted in sub-clinical populations.
7. As to the dating of consciousness, studies have shown that cave art does not require consciousness, dealing a blow to those who would wish to date consciousness to this much earlier period.
8. Also on the dating of consciousness, studies of dreams in classical antiquity show that the earliest recorded dreams were all "visitation dreams," consisting of a visitation by a god or spirit that issues a command -- essentially the bicameral waking experience of hearing verbal commands only during sleep. It is not until after consciousness develops that dreams take on the conscious narratization we are familiar with today. Thus modern dreams are consciousness operating during sleep, and the study of dreams in the ancient world add further confirmation of Jaynes's dating for the development of consciousness.
Much more could be said here, but I will leave it at that at least for the moment. Again, any of these predictions could have been refuted, had the evidence gone the other way. Yet the more we learn, the more the evidence seems to support the various aspects of Jaynes's theory.
Further discussion as well as references to the relevant research for all of these points can be found in the Introduction to The Julian Jaynes Collection as well as the chapter on the new evidence for Jaynes's theory in Reflections on the Dawn of Consciousness.
|