Modal Logic as Metaphysics Timothy Williamson. Modal Logic as Metaphysics is aptly titled. Its main goal is to argue for a metaphysical claim, necessitism, by taking modal logic seriously. He rejects the search for a … In Modal Logic as Metaphysics, Timothy Williamson argues for positive answers to those questions on the basis of an integrated approach to the issues, applying the technical resources of modal logic to provide structural cores for metaphysical theories. The book provides a rigorous introduction to the technical background—for example, concerning possible worlds semantics for modal logic and the interpretation of higher-order quantifers—needed to understand metaphysical questions in modal logic, as well as an extended argument for specific answers to them. Necessitism says that necessarily everything is such that necessarily it is identical with something. There was a lively dispute in the 17 th century about the relationship between God and modality. Ambitious new work by one of the world's leading philosophers; Challenges long-held assumptions; Promises to change the philosophical agenda A final and underexplored topic in Spinoza’s modal metaphysics concerns what we might call the ground of modality.