ding to the objector, it is not. There we noted the dialectical limitations of such counterexamples, namely the contentiousness of their main premise. But compatibilists have often been guilty of what seems to be the opposite mistake. Namely, they have offered theories of ability which show abilities to be compatible with determinism, and have argued from this to the claim that such abilities are indeed compatible with determinism.
The shortcomings of this strategy are nicely diagnosed by Peter van Inwagen. After surveying the local counterexamples that arise for various hypothetical theories of ability, van Inwagen imagines that we have arrived at the best possible hypothetical theory of ability, which he labels ‘the Analysis’. van Inwagen then writes:
What does the Analysis do for us? How does it affect our understanding of the Compatibility Problem? It does very little for us, so far as I can see, unless we have some reason to think it is correct. Many compatibilists seem to think that they need only present a conditional analysis of ability, defend it against, or modify it in the face of, such counter-examples as may arise, and that they have thereby done what is necessary to defend compatibilism. That is not how I see it. The particular analysis of ability that a compatibilist presents is, as I see it, simply one of his premisses; his central premiss, in fact. And premisses need to be defended. (van Inwagen 1983, 121)
van Inwagen’s point is that, provided the incompatibilist has offered arguments for the claim that such abilities are incompatible with determinism—as, in van Inwagen’s presentation, the incompatibilist has—the production of an analysis is as yet no answer to those arguments. For those arguments are also arguments, inter alia, against the compatibilist’s favored account of ability.
There are, then, several obstacles for the compatibilist who wishes to appeal to an account of ability in defense of compatibilism. First, there is the general difficulty of actually giving an extensionally adequate theory of ability. In addition, we have now turned up a couple of more specific challenges to the compatibilist. There is van Inwagen’s point just outlined, namely that arguments for the incompatibility of abilities and determinism are, inter alia, arguments against any theory of ability that is congenial to the compatibilist. And, finally, there is the point that we encountered in our discussion of the new dispositionalism in Section 5.1, which is that certain platitudes about ability — in particular, those involved in certain judgments about moral responsibility — may be recalcitrant to compatibilist treatments. Taken together, these points seem to pose a serious obstacle to any theory of ability that is both compatible with determinism and in accord with our ordinary judgments about what ability requires.
What is the compatibilist to say in light of these obstacles? One response is to make a distinction between two kinds of compatibilist project. (Compare Pryor 2000 on responses to skepticism). One project is to convince someone moved by the incompatibilist’s arguments to retreat from her position. Call this ambitious compatibilism. For precisely the reasons van Inwagen gives, it is doubtful that any theory of ability will suffice for a defense of ambitious compatibilism. There is another project, however, that the compatibilist might be engaging in. Let us say that, for some reason or other, she herself is not convinced by the incompatibilist’s argument. She is still left with an explanatory burden, namely to explain, if only to her own satisfaction, how it could be that abilities are compatible with the truth of determinism. Here the compatibilist’s aim is not to convince the incompatibilist of the error of her ways, but simply to work out a satisfactory conception of compatibilism. Let us call this modest compatibilism. This distinction is not often made, and it is not always clear which of these projects classical compatibilists are engaged in. If the latter project is indeed part of classical compatibilis