While the question concerning the truth of determinism may be an empirical question, that is, it will be settled by the various sciences, philosophers are particularly interested in whether or not the hypothetical truth of determinism would rule out free will. In this lecture, we look at two opposing positions on this issue: those who think that determinism is compatible with having free will (compatibilists) and those think that determinism undermines freedom (incompatibilists). Copyright 2013 Jack Reynolds / La Trobe University, all rights reserved. Contact for permissions.