I loved this book! It was the perfect amount of history, psychology and opinion. It is much more based on psychological studies, facts, figures and research, and is meant to be more of a scientific approach to the subject, rather than a self help book or opinion book. Some might find that approach boring, but if you like the fact driven approach that you can form your own opinions from, this is a great one. I would also recommend the author's follow up book to this, "The good psychopath"