This post is a followup to my recent thinking about Frankfurt-style counterexamples and their implications. In a prior post, I suggested that the only way to avoid such counterexamples is through what I termed "divergences", which are supposed to be instantaneous actions.
I wonder if such is possible. First, the negative path. They can't be deliberative actions, involving a prior intention or decision to perform them. Such deliberative actions will have to be diachronic in temporal import. Further, they couldn't be physical actions. One might try trickery of the following sort: think of the action of beginning to move my arm. But no such action is performed unless my arm moves, and thus this action implies that something happens beyond moment at which my arm begins to move. Moreover, many things happen in the small duration from when I first try to move my arm to the moment at which my arm begins to move. Think of playing "slap" as a kid and experiencing the frustration of finding your hands moving too late, even though you saw the slap coming and began the process that resulted in your hands moving.
You might be unmoved, thinking that I'm ignoring the obvious point that there is a very first instant at which motion of the arm or hands begins. Yes, there is, but it is not clear that there is an action here. There is, of course, the event in question, but not every instantaneous event involved in action is itself an action.
So, it appears we should look at mental acts such as tryings if we are to find instanteous actions. But here there are worries about vagueness that creep in. Suppose you are deliberating about what to do, and the end result of your deliberation is the action of moving your arm, which includes the action of trying to move your arm and trying to begin to move your arm (only the latter has any hope of being an instantaneous action).
Even if the beginning of the movement of your arm is an instantaneous event, it is not obvious that your trying to bring about this instantaneous event is itself instantaneous. We might gerrymander here, however: talk instead of the trying which is contemporaneous with the beginning of the motion of the arm. (One gerrymandering we should resist, that
Even here, though, I think there is a problem. It strikes me as obvious that it is vague when your arm begins to move, and hence vague when the trying begins that is contemporaneous with this beginning.
If all this is right, then to maintain that this particular trying to begin to move your arm can be an instantaneous action requires adopting an epistemicist view of vagueness. Let me speak with the vulgar about this, in the way discussions of vagueness usually proceed. Suppose vagueness is really "in the world," so that there are moments of time at which you've clearly begun to move your arm, and moments of time prior to the moments in the penumbral region where it is not clear whether you've begun to move your arm. In order for the action to be instantaneous, on the assumption that vagueness is in the world, every acceptable precisification of the action in question would have to assign just one moment of time to the action in question. But I can see no reason for thinking that this would be a requirement on an acceptable precisification, and besides that issue, the usual demands on precisification identify the thing in question with what would be true about it on every acceptable precisification. Yet, if every precisification made the action instantaneous, nothing would be true about the action in question regarding its temporality on every precisification.
OK, this was much too fast and loose, but I hope you see my concern, which is simply this: am I right that if you want to avoid FSC's, you'll have to be an epistemicist?