I'm slowly churning out a series here; and by slowly, I mean that I haven't even gotten around to the point of the series yet. As I noted in the beginning, some of the points in the series are very indirect, and the first two certainly were. I'm still not going to be talking about free choice itself yet, but I get a bit closer by looking at the opposing position. I still haven't worked out the formulation of this point to my satisfaction, and in itself it's a limite one, but I think it's interesting.
Point # 3: Determinism has problem giving content to possibility.
(Keep in mind that by 'determinism' I mean a causal thesis.)
We often say that something (let's call it A) might have been different. One way of understanding this is to take it to imply that A could have been different if and only if A's causes had been different. This is, in fact, often the case; when I'm talking about what could have been different about the way a stone fell to the ground, I don't usually go about assuming that the stone had its own power to fall differently than it did, but that (e.g.) the interposition of different causes would have changed the way it fell to the ground.
The only way there is real possibility here, however, is if the causes themselves could have been different - otherwise, the discussion is per impossibile and (as one might guess) that doesn't bode too well for allowing genuine possibility. So to explain the possibility of A's being different, we have pushed the matter back to the possibility of A's causes' being different, and this has to be a genuine possibilty or we have actually mired ourselves in a contradiction. On the assumption that A's being different is really possible, our explanation of that possibility has to allow for it genuinely to be a possibility.
You can tell, I'm sure, where this is heading. I see four responses that can be made to this problem:
a) infinite regress;
b) the achievement of state by appeal to mere chance;
c) the achievement of state by appeal to a cause 'not determined to one';
d) the denial that anything is genuinely possible, other than what actually is.
(a) is contradictory unless it is combined with (d); so (a) as it were collapses into (d). (c) is anti-determinist and so would presumably want to be avoided by a determinist. This leaves (b) and (d). I have no knock-down response to (b); in part because I have difficulty seeing what it would actually be. For (b) to be the case, we must at some point reach a level or system that allows for chance; and in that case it would seem to be the level or system that really does the grounding of possibility. So (b) seems to collapse either into (c) or (d); I don't see any way to maintain it on its own.
So this suggests that the real account of possibility has to be either in terms of (c) or (d). And, indeed, I think both of these have merit; (d), for instance, is a little counterintuitive, but there are a great many clever ways to allow for (d) that still allow us to talk about possibilities without giving any real metaphysical status to them. So I don't consider this Point to be a refutation of determinism, or anything of the sort. Its significance is that it is a bottleneck associated with a number of more serious issues; thus I am getting it out in the open before those issues come up.
According to my notes, the next few points will deal with issues more strictly relevant to the topic of free will. So I'm getting around to the actual subject of the series! Yay!