Novak investigates a belief called the Binary Soul Doctrine (BSD) which states simply that humans possess two souls which split at death, the conscious going on to reincarnate again and again, while the unconscious ends up in a type of limbo judging itself for all eternity.

He goes on to explain that long ago the BSD was the primary belief of a single world religion, which since has been broken into more and more fragments. However, he claims that twentieth-century findings, including the work of Freud and Jung, as well as findings of modern neuroscience and Near-Death research, has...