An interesting examination as to how genetics can effect our mental disposition. Honestly, I did not like the book too much as the author tried to weave threads of personal drama into the text, after which I would look up and wonder why she had wasted my time with the personal interlude.
Interesting tidbit: Something happens in the brains of young people between 20 and 25 that significantly decreases the chances of them remaining religiously vigilant (beyond going to church because their parents tell them to).