Friday, 10 August 2018

Notes on Modality

Some notes from my post-PhD attempts to get back to the really deep problems surrounding modality.

The truth-conditions framing of the puzzle of modality makes it vividly felt. In the case of subjunctive (counterfactual) modality, it even leads to a fruitful answer. But at base, puzzlement remains, and the seeds for solving it are not to be found in the truth-conditions frame.

Likewise, I think, for a grounding frame. However, if grounding is thought of in explanatory terms, there may be a way in.

One problem with the truth-conditions frame is that not everything can be given informative truth-conditions, including discourse which we are not inclined to problematise. Actually describing and isolating surprising features of modal discourse, e.g. with concepts like ‘intensional’, ‘hyperintensional’, ‘referentially opaque’, gives something beyond the general appeal to the question of truth-conditions. Something more to work with. This suggests that a frontier here is: giving better and more refined such descriptions.

Another frontier which is easy to neglect once you take modality philosophically seriously, but really ought not to be neglected: what is it that is bothering the skeptic? What might their view come to?

Falsity in conventionalism. Elements of truth. (Later Putnam on H20.)

‘You can problematize anything like that’ (of the truth-conditions frame). Yes, but today it is this what we have problematized. And you haven’t solved it by pointing that out.

(When does, and when doesn’t, that sort of response - ‘You can always…’ - work? (Compare the perfect island objection to the ontological argument.) Well, the problems are distinctive in the case of modality and the truth-conditions frame. The truth-conditions frame is not just a trick that does the same thing every time, so to speak.)

A couple of particularly deep problems of modality get bypassed, partly because the area is so fruitful and leads to other investigations. (E.g. subjunctive modality’s relation to the a priori. The problems of epistemic modals.)

My PhD research trajectory is an example of such a deflection.

Unity of modality - another problem. Why the same words for all this? (Think about this question and how there may be no satisfactory answer. Here it may be worth trying to imagine other possibilities.)

The unity problem can seem silly in a way, but we can’t really answer it, or say convincingly why we shouldn’t have to. What, exactly, if anything, is wrong with the question?

‘Obstacles’: just shiny problems we get attracted to, distracting us from the big game? Or real obstacles that we can’t just pass by if we want? I.e. does not clarifying the relationship of subjunctive modality to the a priori threaten to make trouble for our efforts at the deeper problems.

The problem under the truth-conditions frame is closely related to the metaphysical feeling of mystery. (The feeling of a ghost.)

Idea: modal yearning is a diffuse yearning for models, systems.

In this way the problem of modality boils down to the general problem of metaphysics.

Modal yearning as a useful heuristic, which then gets a metaphysical application. A metaphysical interpretation.

I look at things in a peculiar way and feel the problem of modality.

This modal yearning angle also explains the attraction of necessitarianism. That doctrine is a soothing balm to one whose modal yearning is bothering them. The pressure to find the system is off. (God’s mind. Copy of the world.)

‘Eliciting the problem’.

My former teacher McDermott’s odd view on metaphysical modality - that it coincides with physical - can make better sense if we think of the dynamic between ‘This is the best deserver of the name’ and ‘Nothing deserves the name’. Or: ‘I don’t know whether anything deserves the name’. ‘I can’t tell what it would take to deserve the name’.

The metaphysically wary person may yet be forced into trouble with wedge-driving argument. ‘Well, you must admit we could have sat over there instead?’, ‘You must admit that we couldn’t both have sat here and not sat here?’

I may be a skeptic myself, if that just means that no one notion deserves a name like ‘metaphysically necessary’. But I used that term as the received label for a (type of?) concept I was interested in.

Sometimes, when thinking skeptically about the puzzles of modality, a realistic impulse asserts itself. Then, it begins to seem like denying the existence of some kind of basic, metaphysical space of possibilities is tantamount to denying that there is a real world.

What does it mean to say that the world has moving parts?

‘There is no privileged system of the world, no privileged way of identifying moving parts and their ranges of movement.’

It is quite easy to feel skeptical when pondering the idea of a complete space of possibilities, or possible worlds.

(There is a use of words like ‘fixed’ in philosophy which I want to call idiotic, or at least very crude. ‘So-and-so believes in fixed meanings’. ‘A fixed set of possible worlds’.)

Given this picture of the complete space of possibilities, we might ask: what is the alternative?

The picture all by itself isn’t harmful, presumably. It can be applied in a way that is not guilty of anything.

* * *

(The below section of these notes was prompted by reading a draft paper by John Burgess called 'Modal Logic in the Modal Sense of Modality'.)

My thought that the deep puzzle was there before Kripke, and that Kripke’s innovation’s main consequence with respect to it was a clearable obstacle, is there in Burgess. That the a priori bit at the core of modal epistemology is still clearly there doing its thing, and that this really just takes us back to where we were before Kripke, as far as the deep puzzle is concerned.

It is interesting that Burgess, when he wants to get to the heart of the matter surrounding the difference between views on which necessity ‘derives from us’ and those on which it doesn’t, uses theological language. He then notes that this would have been a natural way for philosophers in the 17th and 18th centuries to discuss it, but that we probably must today take it as still metaphorical. (And I think it clearly is, even from most theistic perspectives, if they be at all sophisticated.) And so arguably this theological gloss is not much better than the ‘origin’ talk. So he says he’s going to try again.

The next attempt ends up being based on the metaphors of reflection and projection. The modal facts are there, part of the world as it it in itself, vs. they aren’t, rather being a projection of our interests. Burgess, getting into profound waters, writes:

Perhaps I should give up the attempt to get rid of all metaphors, and admit that the two views I am discussing are not so much philosophical theses or doctrines as ‘metaphilosophical’ attitudes or orientations: a stance that finds the ‘reflection’ metaphor congenial, and the stance that finds the ‘projection’ metaphor congenial. But let me try a third time to describe the distinction between the two outlooks in literal terms, avoiding optics as well as theology.

Now comes the attempt:

To begin with, both sides grant that there is a correspondence or parallelism between two items. On the one hand, there are facts about the contrast between what is necessary and what is contingent, for instance, between 29 being a prime number and 29 being the number of years it takes for Saturn to orbit the sun. On the other hand, there are facts about our usage of modal auxiliary verbs such as ‘would’ and ‘might’, and these include, for instance, the fact that we have no use for questions of the form ‘Would 29 still have been a prime number if such-and-such?’ but may have use for questions of the form ‘Would 29 still have been the number of years it takes for Saturn to orbit the sun if such-and-such?’ The difference between the two sides concerns the order of explanation of the relation between the two parallel ranges of facts.

And what do I mean by that? Well, both sides grant that ‘29 is necessarily prime’, for instance, is a proper thing to say, but they differ in the explanation why it is a proper thing to say. Asked why, the first side will say that ultimately it is simply because 29 is necessarily prime. That makes the proposition that 29 is necessarily prime true, and since the sentence ‘29 is necessarily prime’ expresses that proposition, it is true also, and a proper thing to say. The second side will say instead that ’29 is necessarily prime’ is a proper thing to say because there is a rule of our language according to which it is a proper thing to say. This formulation of the difference between the two sides gets rid of metaphor, though it does put an awful lot of weight on the perhaps fragile ‘why’ and ‘because’.

Here the late Wittgenstein passage (from PI 590 - quoted below) can get in between these views. The explanation can go through language to the world, so to speak. What we have use for is not a completely arbitrary matter, if we think of the used items as not bare signs, but signs in a system of language, a body of usage.

...even supposing the pragmatist view is the right one, and the problems of the epistemology of modality are dissolved, still the pragmatist side has an important unanswered question of its own to address. The pragmatist account, as I formulated it earlier, begins by saying that we have certain reasons, connected with our various purposes in life, to use certain words, including ‘would’ and ‘might’, in certain ways, and thereby to make certain distinctions. What the pragmatist owes us is an account of what these purposes are, and how the rules of our language help us to achieve them. Addressing that issue is or ought to be at the top of the pragmatists’ to-do list.

I think this above bit needs careful thought, and that we need to be on guard against oversimplifying ideas about language having a purpose. Its multifaceted character needs to be kept in mind here. It seems to me that the reasons and the purposes aren’t really to be identified, and aren’t really the focus anyhow. We have rather to look into language itself, the working of it, and what we can and can’t ‘do something with’ - this doesn’t require that we have a settled idea of what we want to do with language. So I think there is a way which falls on the ‘pragmatist’ side of Burgess’s line, in that language (meaning) gets into the explanatory act, but where the to-do list doesn’t look like Burgess says it does or ought to.

After discussing a modal ship of Theseus paradox:

Moreover, if the question ever did prove to be, in some specific case, of practical importance, then according to the pragmatist view we could then settle it by fiat, making a new rule for ourselves, since it is rules we have made to which the answers to all questions about modality are ultimately to be traced.

This is dubious to me. Sometimes ‘making a game more definite’ can be protested to be really just moving to a different game. And thus there is, I think, an important sense in which the original question was inherently borderline, inherently not a clear case. Compare ‘Is this man tall?’ (where he’s sort of tall but not really). There’s something wrong with saying that we can just stipulate that the answer to this is ‘yes’. For then we have a concept (attached to ‘tall’) which is just different from the one we had where we didn’t know what to say.

This discussion of Burgess doesn’t get into the weeds of the whole space of possibility, how extensive it is, etc. Or the idea that there’s a lot of indeterminacy there, or actually different notions going by the name ‘metaphysical necessity’. Rather, he just takes a fairly standard off the shelf picture of there being some modal facts here, and contrasts two attitudes to the origin (metaphorically), optics (metaphorically), or explanation (non-metaphorically but perhaps ‘fragile’) of those facts.

‘By contrast, to those who take a pragmatist attitude there will only be the potential for a practical problem, a potential that is thus far apparently unrealized, and that if it ever were realized could always be solved by fiat.’

This I don’t think is right. Similarly I want to rebel against Burgess’s idea about what is on the to-do list of his pragmatist. To be fair, he stipulates that his pragmatist starts with the idea of ‘certain interests and purposes’, but if the core of the pragmatist attitude is just that explanations of modality go through language and meaning, then this starting with ‘certain interests and purposes’, and their foregrounding, seems to me to be an optional extra, and one which I would want to consider doing without.

This, I think, leads to a stronger position. One advocates going through meaning when explaining modality, but also is careful to be faithful to language and meaning as it really is - not a thing with ‘certain purposes’ in any strong sense, and also something which can be inherently indefinite (i.e. that certain expressions and concepts are inherently not sharp, and can’t be made definite by ‘fiat’ without changing the game).

Taking this position, it becomes clearer why we scratch our heads in some cases, and don’t just consult our purposes and lay down new rules.

* * *

One problem with the basic intuition pumping ‘We could have done otherwise today’ way of motivating the concept of metaphysical modality is that it admits of a retrospective epistemic reading which does not obviously imply anything about ways things really could have been.

Here it might be thought: for it to become clear that we mean metaphysical rather than retrospective epistemic modality, we need negative examples - necessities, i.e. claims that such and such could not have gone otherwise. The thought is: if that’s right, and it’s not right under the retrospective epistemic reading, then there must be another reading.

* * *

Trying to really follow through on a maximally realist, metaphysical viewpoint is worth doing. Call the facts objective, say they aren’t projections, talk about our intellectual access to them and let yourself have a special way of knowing. Work in that framework and then see what the questions are.

One that hasn’t been given enough attention in my view is ‘is “Necessary” vague?’. The sort of default thought is perhaps that it is not for the hard-core realist but is for the projectionist. But that’s not very compelling once you really think about it. (Tallness is real, some things really are heaps, etc.)

Idea of a system we could understand which governs the metaphysical modal space. Would this not be a kind of once and for all solution to conceptual possibility questions? (Or would you first have to find a reduction into the terms of the system?)

* * *

The 'broadly logical' terminology for metaphysical modality as a promissory note.

Note how naturally it comes to say 'It doesn't *make sense* to talk about this table having been made of ice'. 'It doesn't make sense to talk about Queen Elizabeth being born of different parents'. (*If* you're in the mood to say those things are metaphysically impossible.) 'It doesn't make sense to talk about Hesperus being distinct from Phosphorus'.

When it is put in terms of sense like this, the matter seems far less final. One thinks 'Well, maybe it could make sense in certain circumstances'. (Not so for other things. For of course we don't just mean 'these words could be given a meaning'.)

Note that these natural claims about what does and does not make sense with respect to counterfactual scenario descriptions do not parallel claims about statements about the way things actually are. It does, for instance, make sense to talk about the table actually being made of ice, or Hesperus perhaps not being Phosphorus after all.

Problem for relating modality to meaning: why, "in the abstract", would meaning be relevant? A picture: the world as a kind of machine with a space of configurations. Those are the possibilities. Our ideas or models are only a guide to the extent and nature of these insofar as they reflect the world. In any case, the order of explanation should not put meanings at the base. Our ideas or models or sentences can meaningfully assume such and such configurations *because* the world is like that.

Response: This brings out that the point of bringing in meaning isn't to block out the world. It's not that we have some end goal of cutting it out and just looking at some isolated language/thought system and explaining modal status in terms of its constitution. Rather, it's that there is a harmony there, and that we go *through* our representations to the world. Through meaning to modality. (But here I feel I'm getting too glib.) The idea that, if we don't do that, we end up stuck.

Look here at particular cases.

When there's an impossibility, one might say, it is only because our conceptions or expressions possess degrees of freedom not possessed by the world.

But something seems to have gone wrong already with that thought. Think about how poorly ideas about, say, the necessity of origin and constitution fit with this picture. (As though there were this thing, the table (or the Queen), which could be manipulated some ways but not others. But of course the table and the Queen are not 'elements' of the world, so to speak, so we feel that this picture is inappropriate. This relates to Quine's idea of the "museum myth".)

The issue of whether there is a single, main concept of metaphysical modality is important. As too is the issue of vagueness. (Kripke's results are negative - whatever may be possible, this isn't.)

Drive towards thinking there is a single concept may be bound up with a yearning to find the system - a generalised, metaphysicalised natural thinking impulse. (Necessitarianism as a balm.)

The one other bit, I think, although it may be implicit in part of the above, is this: the feeling that what our ideas or talk permits may just reflect ignorance or prejudice. Now, there is something to this, but it easily gets out of control or totalised. (This pattern-matches with the philosophical point that we couldn't be wrong all of the time in, say, arithmetic.) (Note that we can, in one fell swoop so to speak, perform radical "manipulations" with our pictures - p-zombies, e.g., or a world with just one atom perhaps, or a non-physical world. But also note the uneasiness which comes with it, the head-scratching aspect, which we don't normally have with clear examples of alternative possibilities.)

Finally, something I think is emerging only dimly now but is important, perhaps very important: the 'leaving it ragged' stuff, the 'making room for head-scratching' stuff. I think some kind of statement of the potential importance of that would be good to have.

* * *

You might ask: what does the credential matter? What follows from it? This is a hard, but I think suggestive, question.

One point: naturalness of ‘doesn’t make sense’ locutions in explanations of Kripkean necessities. Also, making sense in the relevant sense does have to do with the world: not all configurations permitted by the system of language looked at in isolation have the right kind of usability - lack a special status. And the world plays a role in that. (PI 590 passage.)

(The passage referred to above is from section 590 of Wittgenstein's Investigations and I mention it again below. It runs:
[...] So does it depend wholly on our grammar what will be called (logically) possible and what not,—i.e. what that grammar permits?”—But surely that is arbitrary!—Is it arbitrary?—It is not every sentence-like formation that we know how to do something with, not every technique has an application in our life [...].)

One tries to put meaning in the picture by saying: this proposition is one of those whose necessity is guaranteed by what it means (not that they all are - the C. Anthony Anderson point about disjunctive cases): no statement with that meaning could have been contingent. But if one has an extensionalist view of meaning - what is picked out - then this will automatically be true of all necessities. So that doesn’t distinguish the view of the philosopher who wants to have meaning in the picture, in some sense, in their philosophical understanding of modality.

If you have an internal aspect of meaning, then you can perhaps still put the point in terms of necessitation. Still say something that distinguishes from an out-in-the-worlder. Otherwise, looks like you need something like grounding or explanation.

A bare configuration - one we can sort of do something with - one we can do something with.

When you make the world part of the explanation for why a construction doesn’t have the credential - doesn’t have modal genuineness - the meaning view may seem to collapse into an ‘out there in the (nonsemantic) world’ view.

What is so important about having meaning in the picture? What is wrong with the out there in the world view? One problem is that when we try it, and try to talk explanatorily about modal facts, we shoot past the question of meaning - we try to talk in the object language about modally genuine and non-modally-genuine situations. We as it were beg the question in favour of possibility. ‘The world state where Hesperus, that very object, is distinct from Phosphorus, that very object, is an impossible one’. One wants to object that in a sense “the world state” isn’t there.

You may end up representing modal reality in a way which invites the thought that it could have been different. (Stark with modal realism.) Or, you end up with a mysterious ontology of things which you say could not have been different - this gets represented as a kind of super-structure. Now, I think the person who wants meaning in the picture is sometimes feeling here that there’s a kind of inappropriate bedrock - that there’s helpful stuff which is left unsaid if we adhere strictly to an ‘out there in the (nonsemantic) world’ view. (Here recall how it’s quite natural, when explaining the metaphysical necessity of identity, to say something like ‘Given that Hesperus is Phosphorus, it doesn’t make sense to talk about Hesperus, that very thing, not being Phosphorus, that very thing. You’d as it were be saying that this one thing is distinct from itself.’ The movement of thought here is something like: don’t look for, as it were, a counterfactual possibility that is being ruled out as impossible, rather see how there is no such thing answering to that name.)