“Metaphysics,” Leibniz declared, “is natural theology.” In his illuminating new book, Michael Griffin builds a compelling case that this dictum applies especially well to Leibniz's metaphysics of modality, which cannot be fully understood apart from its theological context and aims. In particular, it cannot be fully expressed in terms of the standard contemporary possible worlds semantics that Leibniz did so much to inspire.
The book's seven chapters fall naturally into three groups, each with its own distinctive central topic. These are the ontological argument and the necessity of God's being (chapters 1 and 2); the necessity of everything actual and the actuality of everything possible (chapters 3 and 4); and God's knowledge concerning what free agents would have done (chapters 5, 6, and 7). For each topic, Griffin gives particular attention to Leibniz's relation to one or another distinguished predecessor; indeed, chapter 1 is almost exclusively devoted to Descartes, more...