This book is atrociously bad. It's central premise assumes you believe in the supernatural, and if you don't it won't convince you of anything. After reading 150 pages, I did not encounter a single scientific fact. The author makes allusions to a supernatural realm based on his personal interpretations of cave art, as well from his very typical hallucinogenic drug experiences. Early on in the book he mentions the grief and guilt he feels for not being with his father while he was on his death bed and uses this as motivation in his search for a supernatural realm. Wow, now isn't that subjective?!! This book is a non-serious, unscientific, uninformative, leisurely read which won't impress any logical thinker. A complete waste of time.