Kevin Timpe is William Harry Jellema Chair in Christian Philosophy at Calvin College, and a former Templeton Research Fellow at St. Peter's College, Oxford University. His research is focused on the metaphysics of free will and moral responsibility, virtue ethics, philosophy of disability, and issues in the philosophy of religion. He is the author of Free Will: Sourcehood and its Alternatives, 2nd edn (Bloomsbury, 2012) and Free Will in Philosophical Theology (Bloomsbury, 2013). He has edited a number of volumes, including Virtues and Their Vices (OUP, 2014) and Arguing about Religion (Routledge, 2009). He is currently working (with Meghan Griffith and Neil Levy) on The Routledge Companion to Free Will.
Daniel Speak is Associate Professor of Philosophy at Loyola Marymount University. He has recently served as a Visiting Research Fellow at Biola University's Center for Christian Thought and as a Senior Fellow at the Center for Philosophy of Religion at Rutgers University. He thinks and writes principally about the metaphysics, ethics, and epistemology of free will and about related issues in the philosophy of religion. His articles have appeared in The Philosophical Quarterly, Faith and Philosophy, and The Oxford Handbook of Free Will, among others.