In this classic work William James explores the psychology of religion, applying scientific method to a field that had previously been treated as theoretical, abstract philosophy. This 2002 centenary edition celebrates the 100th anniversary of this landmark text. It includes new introductions by Jeremy Carrette and Eugene Taylor, as well as a fully revised index. James believed that individual religious experiences, rather than the precepts of organized religions, were the backbone of the world's religious life. His discussions of conversion, repentance, mysticism and saintliness and personal religious observations and experiences all support his thesis. James' pluralistic view of religion led to his remarkable tolerance for extreme forms of religious behaviour, a willingness to take risks in formulating his own theories, and a welcome lack of pretentiousness in his observations on how an individual stands in relation to the divine.