Jump to about 11:45 where it gets a bit more interesting then just talking about gameplay. Basically, George starts talking about the supernatural(or lack thereof) bits of this game and brings up the concept of
bicameral mind theory, or the idea that Ancient people processed the world differently then we did on a biological and psychological level, and when they heard gods and sprits, it was more akin to what we'd consider symptoms of schizophrenia. I don't know how much there is to that and I don't have the background in Neuroscience, Psychology or Anthropology to really judge if it's bullshit or not. It was an interesting Segway regardless.