Digging Deeper into Determinism

Abstract

Arguments for the incompatibility of free will and determinism commonly depend on the claim that if all events are caused then, for every action, the agent could not have acted otherwise than he did. But as Winston Nesbitt and Stewart Candlish have recently pointed out ('Determinism and the Ability to do Otherwise', Mind, I978, pp. 415420), this claim is far from obvious, even ignoring the many and sophisticated attempts to avoid it by an appropriate analysis of causation, or of 'could have', or both. 'For while it is clear why it should be thought that if it is determined that one will do something on a given occasion then one will not in fact do anything else on that occasion, it is much less clear why it should be thought that if it is determined that one will do something on a given occasion, then one will be incapable of doing anything else on that occasion' (p. 415). Surely determinism does not have 'the peculiar consequence that on any particular occasion, one's abilities are restricted in number to just one, namely the ability to do precisely as one does' (p. 4I7)! What has happened, Nesbitt and Candlish suggest, is that incompatibilists have committed the familiar modal fallacy of arguing from LCpq to CpLq, by arguing from 'Necessarily, if determinism is true, then one will not do otherwise than one does on any particular occasion' (which Nesbitt and Candlish are themselves prepared to accept) to 'If determinism is true, then one cannot do other than one does on any particular occasion' (which is what the incompatibilist's argument requires). Now first of all it is worth being clear that, in claiming that the agent could not have acted differently, the incompatibilist need not be claiming that his abilities are restricted to just one. Take an example where it is as clear as it ever can be that I cannot do other than what I am doing: where I fall over a cliff and, lacking any parachutes, jet thrusters or efficacious magic, plummet towards the ground at an acceleration of 9-8 metres per second per second. Yet even then I do not lose my ability to type or drive a car-at least not until I hit the ground-any more than I lose my ability to drive when I am in my study and my car is safely locked in my garage. What is the case, rather, is that I am not, in those circumstances, in a position to exercise those abilities. It is for this reason that I have elsewhere distinguished the 'can' of ability from the 'can' of being able (see 'The Can of Being Able', Philosophia, I976, sec. i). The question at issue in the free will debate is not whether determinism deprives me of my abilities, but whether it means that I am, on any particular occasion, unable to exercise any such abilities except those which, at the time, I happen to be exercising. Nevertheless, however we interpret the 'can' it remains true, as Nesbitt and Candlish insist, that what follows from determinism is not that the