The Origin Of Consciousness In The Breakdown Of The Bicameral Mind Julian Jaynes 1976
This has to be one of the best books i've ever read, originally took me 6 months to get it via the library, then bought it for something like 50p on ebay, and here it is Free!
It explains in thorough detail how some people simply are not conscious, and how the conscious people exploited that.
A bit like today maybe?