The cognitive science of religion is a rapidly growing field whose practitioners apply insights from advances in cognitive science in order to provide a better understanding of religious impulses, beliefs, and behaviors. In this book Ilkka Pyysiäinen shows how this methodology can profitably be used in the comparative study of beliefs about superhuman agents. He begins by developing a theoretical outline of the basic, modular architecture of the human mind and especially the human capacity to understand agency. He then goes on to discuss examples of supernatural agency in detail, arguing that the human ability to attribute beliefs and desires to others forms the basis of conceptions of supernatural agents and of such social cognition in which supernatural agents are postulated as interested parties in social life. Beliefs about supernatural agency are natural, says Pyysiäinen, in the sense that such concepts are used in an intuitive and automatic fashion. Two dots and a straight line below them automatically trigger the idea of a face, for example. Given that the mind consists of a host of such modular mechanisms, certain kinds of beliefs will always have a selective advantage over others. Abstract theological concepts are usually elaborate versions of such simpler and more contagious folk conceptions. Pyysiäinen uses ethnographical and survey materials as well as doctrinal treatises to show that there are certain recurrent patterns in beliefs about supernatural agents both at the level of folk-religion and of formal theology.