Dan Linford

This book critically assesses arguments for the existence of the God of classical theism, develops an innovative account of objects’ persistence, and defends new arguments against classical theism. The authors engage the following classical theistic proofs: Aquinas’s First Way, Aquinas’s De Ente argument, and Feser’s Aristotelian, Neo-Platonic, Augustinian, Thomistic, and Rationalist proofs. The authors also provide the first systematic treatment of the ‘existential inertia thesis’. By connecting the thesis to relativity theory and recent developments in the philosophy of physics, and by developing a variety of novel existential-inertia-friendly explanations of persistence, they mount a formidable new case against classical theistic proofs. Finally, they defend new arguments against classical theism based on abstract objects and changing divine knowledge. The text appeals to students, researchers, and others interested in classical theistic proofs, the existence and nature of God, and the ultimate explanations of persistence, change, and contingency.

Humans constantly produce strings of characters in symbolic languages, e.g., sentences in natural languages. We show that for any given moment in human history, the set of character strings that have been produced up to that moment, i.e., the sum total of human symbolic output up to that moment, is finite and so Turing computable. We then prove a much stronger result: a Turing machine can produce any particular set of symbolic output that we could possibly have produced. We then discuss metaphysical and/or theological systems, e.g., Spinoza’s, Leibniz’s, or Aquinas’s. We argue that any particular metaphysical system could be the output of a Turing machine. We then briefly discuss (i) automated theorem proving, the attempt to generate and/or prove theorems using computers, and (ii) computational metaphysics, the attempt to apply methods from computer science such as automated theorem proving to metaphysics. We conclude by arguing that: (i) computational metaphysics can succeed, at least in theory; indeed, all human metaphysical reasoning could be automated; (ii) computational metaphysics – and indeed metaphysical systems in general – will have the same limitations as Turing machines; and (iii) a number of different methods – not currently used in computational metaphysics – could be used to advance metaphysical research.