There is nothing objectionable about things interfering with exercises of the power of gravity. In fact, gravity itself can be thought of as ‘interfering’ with gravity: the relative movements towards each other of two heavy objects, as dictated by the laws of gravity, will not materialize if a third heavy object is present in the vicinity. The point is quite trivial once we have shed the tendency to think of causes in terms of necessity or universality: what will actually happen is not determined by the laws of any specific feature or power or force, for there may always be other things present with additional features or powers or forces. Abstractly speaking, then, interference with the power of gravity by a playful dog is no different from interference by another heavy object.
But there is a difficulty when we look more concretely at such a situation. For the dog itself is composed of physical particles and chemical stuffs–and these particles and stuffs presumably behave in accordance with their nature, whether they’re inside the dog or not. So how can the dog as a whole make any difference to what its constituent matter is doing?
We must distinguish between two senses of this question. Borrowing Jonathan Lear’s apt distinction: we can put the question either ‘with a skeptical sneer’ or rather ‘with a straight face’ (see Lear 1984). To answer the latter question, which is a genuine inquiry into how there could be such a difference-making on the part of the dog, we need to distinguish matter from material. The matter inside the dog isn’t just matter, for the dog uses it as material.Footnote 12 More concretely: if the dog is to interfere, out of its playful desire, with the falling stick, then that desire must be effective in steering the dog’s constituent matter accordingly. This in turn means that the constituent matter must leave open a range of physical outcomes, which partly constitute the behavioral options open to the dog, to be narrowed down further by the dog’s desires, impulses, and instincts. In this way, then, the dog can make a difference to what its constituent matter does, without of course ever breaking the laws governing that matter.Footnote 13
I will elaborate on this answer to the ‘straight face’ question shortly. But, although this lies strictly outside of the concerns of this paper, let me briefly touch upon the ‘skeptical sneer’ version of that question as well. It can, for instance, take the following shape: by which mechanism does the dog exert influence on its constituent matter? This question is then not to be answered by merely pointing out that the dog uses the ‘mechanisms’ of his muscular system, for instance. What the mechanistic inquiry is after is, rather, a mechanism by which the dog makes its constituent matter (including its muscles) do things that that matter would not be doing ‘on its own’ in the first place. And obviously, the mechanistic inquiry isn’t particularly interested in dogs; it wants to know how substances generally can exercise powers of their own by ‘using’ their materials.
Put in this way, there will be no satisfactory answer–and the reason why there will be no such answer is precisely because it rests on a ‘skeptical sneer’ towards the Anscombean-Priorian conception of interacting substances as such. Compare a similar mechanistic inquiry in the case of the matter itself: electrons, being negatively charged, repel each other–but by what mechanism do they exert such influence? We must say: by no mechanism; rather, it is through having the power of electric charge (among other powers) that electrons can be invoked in mechanistic explanations in the first place.Footnote 14 In short: the categories of substance and power are basic; it is in terms of interacting substances that we can understand what goes on. But this is, to repeat, a highly abstract insight; nothing in the very idea of substance and power prohibits there being composite substances. A dog is such a substance, with powers of its own; these are, on our present picture, metaphysically as well as explanatorily basic.Footnote 15 Of course, much can be said concerning the way in which a dog exercises its ‘agentive’ powers (e.g., by using its muscular system in certain ways), but that more detailed story concerning the dog’s agency will simply take its place within the fundamental, metaphysical conception of it as a substance having certain powers. It will answer our straight-face question for the particular case of the dog, not the skeptical-sneer question.
So much for our brief excursus. Notice that we have finally returned, now, to the casual broadening of the requirement of indeterminism from free agency to animal behavior registered in §1 above. Here is another quote to the same effect taken directly from Anscombe’s discussion of causality:
We could say: of course nothing violates … the laws of the force of gravity. But animals, for example, run about the world in all sorts of paths and no path is dictated for them by those laws …. (C&D: 143; my emphasis)
Again, it is not animals per se that Anscombe seems to be interested in (‘for example’, she writes). Rather, her essay as a whole points towards a more general conclusion: that, on a metaphysical picture of interacting substances, the requirement of physical indeterminism arises as soon as we want to acknowledge substances that have the power to do certain things by using their constituent matter in certain ways–in short, where matter is used as material. And it looks like this is paradigmatically true not just for free agency, and not just for animal behavior either, but for the realm of the living at large.Footnote 16
Thus we arrive at an incompatibility claim of much broader scope that the one usually found among libertarians in the free will debate. However, that doesn’t yet give us the promised varieties of indeterminism and incompatibility. Before we move on to develop those (in §4 below), we need a better grasp on what it means, exactly, to endorse indeterminism, on our Anscombean picture. She herself defines it as follows:
I should explain indeterminism as the thesis that not all physical effects are necessitated by their causes. (C&D: 145)
Conversely, then, determinism will be the thesis that all physical effects are necessitated by their causes. That still doesn’t mean that nothing can interfere with any given case of necessitating causation: it just means that that interference itself then must be the result of a necessitating cause as well. (For instance, a billiard ball’s movement towards the pocket may be interrupted by another ball, which got its momentum from a fine hit by a player’s cue, which is a necessitating cause of movement.) Given the background metaphysical picture of interacting substances, it is always in principle possible that something interferes with a given necessitating cause. But if all that happens involves necessitating causes, then nothing outside of the actual unfolding of events is possible.
Or, at least, that seems to be what Anscombe has in mind when she defines indeterminism in this way. There is, however, a complicating factor: nothing in Anscombe’s definition of ‘necessitating cause’ prohibits there being necessitating causes the effects of which aren’t fully determinate. Take her own example of rabies being a necessitating cause of death (you’re sure to die from it without treatmentFootnote 17): the rabies doesn’t necessitate exactly when, where and how you’re going to die from it–not in every conceivable detail. Thus it may well be that “all physical effects are necessitated by their causes” without it being the case that the future course of events is fully predetermined–i.e., without determinism being true.Footnote 18
In fact, I think this observation adds to Anscombe’s case for her thesis that “[i]t is the [determinist’s claim of] total coverage of every motion that happens, that is a fanciful claim”–which is why she insists that “indeterministic physics … is only culturally, not logically, required to make the deterministic picture doubtful” (C&D: 147).Footnote 19 After all, if necessitating causes indeed leave room for a certain range of outcomes (all of which conform to that which is necessitated, of course), then this may be thought to already provide for the leeway I claimed to be required by the vital operations of living beings, the behavior of animals, and the free actions of thinking beings like ourselves.
And indeed, many of the typical arguments and examples one finds in Anscombe’s essay are intended to show that even if we take the relevant goings-on to be the result of necessitating causes only, still there is no way in which we can conclude that the end result was predetermined (see, for instance, her discussion of the bouncing balls; C&D: 142).
But I do not think Anscombe is entirely clear on this matter in C&D. On the one hand, it looks like her definition of indeterminism, as well as her short discussion of the import of indeterministic physics with regards to the free will problem, assume that unless we have non-necessitating causes, determinism is true. On the other hand, as I just indicated, her overall strategy is one of dissociating the ‘fanciful claim’ of determinism even from the notion of deterministic laws (i.e., laws governing necessitating causes).
We can amend the situation for Anscombe in two ways. At first sight, it may seem that we should simply redefine ‘necessitating cause’ so that it only applies to cases where what is necessitated is determinate in every respect. But it is quite doubtful whether there will then be any necessitating causes. (Briefly put, these would then either have to be governed by laws so precise that they exceed limits of accuracy beyond which we cannot really give meaning to their statementsFootnote 20, or they would collapse to singular (token) causes, which we discussed earlier.) It thus doesn’t look like this solution sits well with Anscombe’s philosophical outlook.
The alternative is to redefine ‘indeterminism’ more specifically as the claim that not every physical effect is predetermined in every respect. Given Anscombe’s preference for the term ‘(un)predetermined’ throughout the lecture (a notion she does not explicitly define), this looks to be the better solution. And it also fits better into the basic metaphysical framework of substance and power against which I have been plotting her considerations. Recall that, on that conception, powers embody the element of generality, which Anscombe regains by rejecting the involvement of universality and necessity in the very concept of causality. Powers point towards their manifestation, we could say, but this ‘pointing’ is not a matter of relating the given, particular situation to a particular manifestation-situation later on. Rather, powers point to their manifestations generically (e.g., rabies leads to death), and such a generic manifestation can materialize in many particular ways.Footnote 21 Thus understood, it becomes clear why determinism would be a ‘fanciful claim’ even if one insisted that there are only ever necessitating causes.
Now that we have sketched out Anscombe’s conception of causality and (in)determinism, let us return to our strong incompatibilist claim and see how it gives rise to varieties of indeterminism and incompatibilism.