Gods, Voices and the Bicameral Mind by Marcel Kuijsten
“Jaynes lists seven factors that he believes caused subjective consciousness to emerge toward the end of the second millennium B.C.E.:
(1) The weakening of the auditory by the advent of writing.
(2) The inherent fragility of hallucinatory control.
(3) The unworkableness of gods in the chaos of historical upheaval.
(4) The positing of internal cause in the observation of difference in others.
(5) The acquisition of narratization from epics.
(6) The survival value of deceit.
(7) A modicum of natural selection.”
