Julian Jaynes in his The Origin of Consciousness in the Breakdown of the Bicameral Mind (1976) presented a grand theory of the development of human consciousness and its relationship to the development of human history. In Jaynes's theory the bicameral mind began to break down in Western civilization around 12 BC. Prior to the breakdown of this two-sided bicameral mind the right hemisphere of the brain had subconsciously made meaning of everyday life. As a meaning-making entity, the right hemisphere transmitted its perceptions to the whole brain. Individuals interpreted such transmissions as the voices of gods speaking to them. After the breakdown humans were no longer blessed by this divine intervention in their lives. As a result, they were beset by anxieties and tensions resulting from the need for truth about the world and the ability to make conscious decisions. Subsequent Western history, Jaynes maintained, thus became a quest for certainty, a search for new forms of authority.
The main themes of the last four millennia in Western culture (some of the same themes are present in other cultures but in differing time-frames) emerge when studied in this Jaynesian context. In the late second millennium BC, many stopped hearing the voices of the gods. By the end of the first millennium BC, those men and women (the prophets and the oracles) who still heard the voices were dying away. From the time of Christ until AD 1000, it was the transcripts of the testimonies of the oracles and prophets which provided our authorization and our volition. In the last 1000 years these writings began to lose their authority. During this millennium the Church found itself challenged by science. Contrary to popular belief, the two forces clashed not over the existence of the divine but over the proper path to divine certainty. Indeed, the scientific revolution was driven by a desire to uncover hidden divinity, that is, a divine plan for the universe. With the coming of the Enlightenment and nineteenth-century scientific materialism this search for a divine plan ran into an ironic detour. The romantic search for God's hand was dismissed as scientists began to posit that there was no room for the divine in a cold, rational universe. Darwin's