introduction

My topic lies on conceptual terrain that is quite familiar to philosophers. For others, a bit of background may be in order. In light of what has filtered down from quantum mechanics, few philosophers today believe that the universe is causally deterministic (or “deterministic” for short). That is, to use Peter van Inwagen's succinct definition of “determinism” few philosophers believe that “there is at any instant exactly one physically possible future.” Even so, partly for obvious historical reasons, philosophers continue to argue about whether free will and moral responsibility are compatible with determinism. Compatibilists argue for compatibility, and incompatibilists argue against it. Some incompatibilists maintain that free will and moral responsibility are illusions. But most are libertarians, libertarianism being the conjunction of incompatibilism and the thesis that at least some human beings are possessed of free will and moral responsibility.

People sometimes wonder why philosophers who believe that determinism is false care about the compatibility question. Those who read on will find a partial answer that has a lot to do with luck. For introductory purposes, the sphere of luck (good or bad) for a person may be understood as the sphere of things having the following two properties: the person does not control them; even so, they affect his or her life.

There is in the literature on free will and moral responsibility a notion of ultimate responsibility that, by definition, requires the falsity of determinism.