Julian Jaynes, in Manfred Spitzer and Brendan H. Maher (eds.), Philosophy and Psychopathology (New York: Springer Verlag, 1990).
Reprinted in Marcel Kuijsten (ed.), Reflections on the Dawn of Consciousness (Julian Jaynes Society, 2006).
Abstract: Verbal hallucinations were studied in a variety of groups. In a sample of hospitalized schizophrenics and a sample of homeless people on the streets on New York City, such voices were often multiple, critical in women, but more often commands in men, and commonly religious. In a carefully randomized sample of normal college students, a questionnaire study revealed that almost a third had “clearly heard a voice when no one had spoken to me.” The voices were identified as parents, friends, dead relatives, or God. From a study of “imaginary playmates,” it was concluded that verbal hallucinations were occurring here also. And a non-verbal group of congenital quadriplegics, who had never spoken but with whom communication would be established, heard voices they identified as God, such voices being usually helpful. Parallels were then drawn between modern verbal hallucinations and what is revealed in ancient texts. Ancient civilizations seem to have been governed by such hallucinations called gods, a mentality known as the bicameral mind. It was concluded that the reason verbal hallucinations are found so extensively, in every modern culture, in normal students, schizophrenics, children, and vividly reported in the texts of antiquity is that such hallucinations are an innate propensity, genetically evolved as the basis of an ancient preconscious mentality.