Timothy Williamson has argued that our capacity for metaphysical modal judgement comes along with our capacity for counterfactual judgement. This passage gives a flavour of his view:
Humans evolved under no pressure to do philosophy. Presumably, survival and reproduction in the Stone Age depended little on philosophical prowess, dialectical skill being no more effective then than now as a seduction technique and in any case dependent on a hearer already equipped to recognize it. Any cognitive capacity we have for philosophy is a more or less accidental byproduct of other developments. Nor are psychological dispositions that are non-cognitive outside philosophy likely suddenly to become cognitive within it. We should expect cognitive capacities used in philosophy to be cases of general cognitive capacities used in ordinary life, perhaps trained, developed, and systematically applied in various special ways, just as the cognitive capacities that we use in mathematics and natural science are rooted in more primitive cognitive capacities to perceive, imagine, correlate, reason, discuss… In particular, a plausible non-skeptical epistemology of metaphysical modality should subsume our capacity to discriminate metaphysical possibilities from metaphysical impossibilities under more general cognitive capacities used in general life. I will argue that the ordinary cognitive capacity to handle counterfactual carries with it the cognitive capacity to handle metaphysical modality. (Williamson, The Philosophy of Philosophy (2007), p. 136. Found in Section 3 of the SEP article 'The Epistemology of Modality'.)
In order to argue for this, Williamson takes a schematic semantic story about counterfactual conditionals:
Where “A>B” express “If it were that A, it would be that B”, (CC) gives the truth conditions for subjunctive conditionals: A subjunctive conditional “A>C” is true at a possible world w just in case either (i) A is true at no possible world or (ii) some possible world at which both A and C are true is more similar to w than any possible world at which both A and ¬C are true.(Formulation from Sec 3 of the SEP article.)
On the basis of this, he proves the following equivalences:
(NEC) □A if and only if (¬A>⊥)
It is necessary that A if and only if were ¬A true, a contradiction would follow.
(POS) ◊A if and only if ¬(A>⊥)
It is possible that A if and only if it is not the case that were A true, a contradiction would follow.
(Renderings and spellings out from the SEP article. The box and diamond are metaphysical modal operators, and the falsum - which looks like an upside-down 'T' - represents a contradiction.)
But this only works because the schematic theory of counterfactuals Williamson adopts is understood as working against a background of a notion possible worlds, where Williamson understands this as the notion of metaphysically possible worlds. This theory deems true all counterfactuals with metaphysically impossible antecedents, and this is crucial to his demonstation of the equivalences on the basis of his assumed schematic theory.
There are lots of reasons not to adopt a theory of counterfactuals which uses the notion of metaphysical possibility in this way. One reason to move away from a theory like this is if you think that there are counterpossibles - counterfactual conditionals with metaphysically impossible antecedents - which have their truth-values non-vacuously. But you might be agnostic about that. For instance, you might be happy with metaphysical modal distinctions but doubt that there are any clear cases where countepossibles have truth-values non-vacuously. In that case you might see no good reason for the backdrop of worlds or scenarios in a theory of counterfactuals to be exactly the metaphysically possible ones. Or, you might be skeptical about the very distinction between metaphysical possibility and impossibility, in which case you won't want to understand the backdrop in a way that involves that distinction. And it seems that you can get most, or even all, of the theoretical benefits of a Stalnaker-Lewis approach to counterfactuals without using that distinction. It doesn't really seem to play a starring role in the theories.
If a semantic theory for counterfactuals which does not draw on any bright line between metaphysically possible and metaphysically impossible scenarios is as good or better than the theory that Williamson uses to prove his equivalences, that seriously undermines the equivalences, and in turn Williamson's story about how we get metaphysical modal knowledge.
(And note that this turns on Williamson's understanding his chosen theory so that 'possible world' means 'metaphysically possible world' - even accepting an identically worded theory, but where 'possible world' is understood in a way which does not involve the distinction between metaphysical possibility and impossibility, would make Williamson's equivalences unavailable.)
I want to explore a 'no clear best deserver' view of the - very inchoate - role that the distinction between (metaphysically) necessary vs. contingent truths is supposed to play.
The idea is that once you drill down in the borderlands, you see that there are different ways of going.
So no clear best deserver. But also: it's not clear that anything is a good enough deserver.
The 'no clear best deserver' hypothesis raises questions: why wouldn't everyone agree? Why would this be news?
One reason might be that there really is a best desever. Or that it seemed like there was a clear best but on further reflection there are competitors and it's not clear that any one has the edge. But I think there's more to say about why this might be news. There is something very natural about thinking that there is some single distinction here. There is a strong inclination to think that there some one major, fundamental distinction between the truths that could have been otherwise and the ones that couldn't.
So if there is a sense in which this is not so - or if we want to be circumspect about it - we could try to tell a positive story about how this comes about.
Also, it is important to remind ourselves that the strong inclination I am speaking of may not be universal, or even normal. (Think of people who encounter this philosophical discourse, feel vaguely skeptical, maybe kind of interested but not particularly compelled, don't sign up for any view in particular, or flirt with some unusual view (an undergrad fellow student of mine defended the view that all truths are necessary in a course essay), and simply move on with their lives and don't ever really think about the matter, except as something some people are concerned with.)
But, at the same time: it's not just some specific problem in some particular subliterature. Versions of it, or closely related things, come up in philosophy at many times and places. And I have the feeling that it springs from a kind of root that also gives rise to certain philosophical thoughts and frames of mind that all sorts of people have.
So, how might it come about? Perhaps: Some kind of drive towards systematic understanding run rampant. Desire to see world as mechanism with discrete states. And the point isn't that that's naive, or probably not true after all, or something like that. But one issue here may be: why should there be one clear best way of seeing the world that way?
It is possible to get into a frame of mind where it seems like there must in some sense be a single or primary set of facts about the possible states of the world, if there really is a world at all. It is like Wittgenstein's demand for substance, for eternal objects, in the Tractatus. It can seem like if the thing you're demanding weren't so, there would be no world at all, or nothing would be true.
There's something here I want to say in connection with this 'no clear best deserver' idea, along the lines of: how little is said when the idea of metaphysical modality is introduced! How could there be enough specific information there - in phrases like 'really could have been that way' - to narrow things right down to a particular, clear distinction! It feels completely "lay", really quite free of theory (but of course you can theorise about 'really' or formulate it in terms of 'some fundamental sense' and then theorise about that).
But on the other hand, isn't that a bit fallacious? Can't specific, detailed things come out of arrangements of ordinary, quite general concepts? And don't, for example, specific seeds produce specific trees, despite being so small?
So this thought needs to be stated carefully. There's not some general rule here that's being appealed to. Still I think there's a point here, a way to see something - a way to break the grip of something.
The words and associated ideas we're using here are quite flexible things, on reflection. 'Things', 'really', 'could'.
You might say there's a kind of naive level of "buying into" the idea of this one major distinction between contingent and necessary truths. Just not thinking about it too much. But then if you've thought about it and seen it threatened or scoffed at or considered uninteresting, but still want to pursue it - OK, now you're after something. Now you have a dream, I feel like saying.
I think, awkward as it is to talk about, there is really no getting away from the fact that there's something fantastic about the idea, something grand. '"How things really could have been" - what could be more interesting than that?!'
* * *
Consider Kripke's suggestive remark at the end of Naming and Necessity about leaving open the extent to which metaphysical modality will turn out to be closer to physical than suspected.
It's remarkable how little investigation or facing up there has been to the issue of how such a thing might be decided. (Williamson talks about 'detailed theoretical investigation' but I can't help but feeling that this is a kind of mirage, like how Russell and the early Wittgenstein palmed off the question of what the logical atoms will turn out to be.)
Decades later, we seem to just have different viewpoints - some rationalists who are far from thinking it coincides more with physical possibility than you might think, and others who are captured by the idea of empirical insight into hard limits (due to what seems to me a kind of misinterpretation of the necessary a posteriori, but working out where the stand offs there lie would be good).
The picture I have now is this: there's a certain inchoate role, inchoate requirement or job description for this idea of the ways things really could have been (metaphysically), and then it recedes into the background when we look at cases and theories. But this needs to be scrutinised more, and this will shed light on skepticism about the notion, and on different positive views.
I don't mind if you settle on a best deserver and are happy with it, but I will want to be clear that this is what is happening, and be wary of an alternative way of thinking about the matter as something which has been investigated and a view found correct. <-- Inadequate, but there is an important feeling here that I don't want any smoke and mirrors.
A large part of the worry is: that this process of coming to rest upon a choice of best deserver gets misrepresented as investigation into how things could have been. A failure to distinguish between getting to a concept and investigating what it applies to. But there are dangers with this hypothesis too.
'Philosophers framed the question of how things really could have been, and detailed philosophical research has led to a convergence on the view that this turns out to be a matter of ...'
In terms of what we want from the term, what gives it its life and feeling of importance - this is so easy to write off as a trifling, preliminary thing. Almost indecent to talk about. But it is very important. And it's amazing how far it reaches, so to speak.
