In chapter 10 we examine the neurology of religious ritual and ritualization rooting it in neurology of stereotypies. Evolutionary sexual conflict theory suggests sex differences in functional aspects of motor stereotypies. Ritural in OCD are xamined as are models of ritual processes such as threat detection theory.

This final chapter offers a sustained textual analysis of the Day of Atonement ritual in Leviticus 16 and theorizes the effects of ritualized behavior and cognitive and material costs associated with the ritual ceremony. Several important theoretical frameworks from the cognitive science of religion (CSR), which aim to study different aspects of religious ritual in particular, are introduced and applied to the biblical text. These include Lawson and McCauley’s ritual form hypothesis, Whitehouse’s modes of religiosity, Boyer and Lienard’s notion of ritualized behavior, and others. These cognitive theories offer a new set of questions and methods for approaching ritual in ancient Israel, departing from more traditional ritual theory. The chapter analyzes the purification or purgation of the temple and the scapegoat ritual using these theories.

In contrast to the cognitively optimal religion in the previous chapter, this chapter examines the theological system in the book of Deuteronomy as an example of cognitively costly religion. Deuteronomic theology is characterized as a highly literate, reflective, and abstract tradition with complex doctrines such as the so-called Name Theology of divine presence, cult centralization, and aniconism or iconoclasm, all of which radically depart from prevailing cultural expectations. Each of these key tenets of the Deuteronomic theology is analyzed within the framework of intuitive and reflective cognition and cognitively costly religion. Moreover, understanding Deuteronomy as a type of costly religion helps to account for the book’s unique emphasis on teaching, repetition, and instruction. Deuteronomic theology is best understood as a form of what Harvey Whitehouse calls the doctrinal mode of religiosity.