This introductory chapter presents the crux of matter that will be analysed throughout the chapters of this book. This will be further clarified by explaining both the overall goal of the book—analysing the position of the scholar in the study of religion and particularly in relation to evolutionary and cognitive sciences of religion—as well as the more specific goal of presenting an in-depth analysis of methodological naturalism. In addition, the introductory chapter also offers a chapter-by-chapter overview of the whole book.