The intent of this book is to use anthropology and cognitive science to "explain" why religious beliefs developed (and are still common) in humans. I started reading this book with the expectation that it was intended as popular science; but it assumed that the reader already had a background in anthropology and cognitive science. Boyer made his explanations using terminology that was unnecessarily complex; and although the meaning could be discerned from the context, it made the narrative into very heavy reading. Furthermore, he made many bold statements without providing evidence, possibly because he figured his readers had a background in this area and knew where he was coming from. The examples he did provide often fell short for me as a scientist--I felt there were too many obvious loopholes to the experiments described, and it was unclear whether these loopholes were addressed. Overall, I think this book may be interesting to someone who has already read a lot of literature in this field, but I wouldn't recommend it to someone with a casual interest, nor as introductory material.