Extreme Religious Behaviours

Certain religious behaviours clearly reduce biological fitness. These behaviours include celibacy along with various forms of asceticism, and rituals that harm the performer. Such behaviours are found in widely different cultures. How is this possible? This book shows that these behaviours (as is religion in general) are by-products of features of the human mind whose evolutionary fitness is beyond doubt and explores those features. Which are those features? This book proposes a twofold answer.