A philosopher of mind and of religion who has written about the metaphysical requirements of free will, Timothy O’Connor is professor and chair of philosophy at Indiana University. He is an honors graduate of the University of Illinois at Chicago where he earned an undergraduate degree with distinction in philosophy as well as an M.A. in philosophy before going on to Cornell University. He studied there on a Susan Linn Sage Fellowship then on a graduate research fellowship and received a Ph.D. in philosophy in 1992. After post-doctoral research at the University of Notre Dame, he joined the Indiana philosophy faculty in 1993 as an assistant professor. Dr. O’Connor spent a year at the University of St. Andrews as a Gifford Research Fellow and was named to his present position in 2005. In addition to research fellowships awarded by Indiana, he also has been the recipient of a fellowship given by the Pew Scholars Program. He has won several awards for teaching excellence. Dr. O’Connor formerly served on the executive committee of the Society of Christian Philosophers. The author of more than thirty papers published in scholarly journals, which explore, among other things, the idea that mental states are ontologically emergent, he is the editor of Agents, Causes, and Events: Essays on Indeterminism and Free Will (1995) and the co-editor (with David Robb) of Philosophy of Mind: Contemporary Readings (2003). His first book Persons and Causes: The Metaphysics of Free Will was published by Oxford University Press in 2000, and he recently completed Contingency: Theism and Ultimate Explanation, which will be published by Blackwell in 2007. It sketches an account of how we are able to know nonempirical facts concerning what is possible and what is necessary, contends that such facts play an essential role in constraining our scientific theorizing concerning the world, and then refurbishes and defends Leibniz’s argument that classical theism provides the best explanation for the ultimate empirical fact of existence itself.