Friday, July 18, 2008

Quantification, Naturalness, Ontology

I’ve posted a draft of a paper ‘Quantification, Naturalness, Ontology’; this is slated for the volume New Waves on Metaphysics, edited by Allan Hazlett – but there’s a while until the deadline, so any comments on it would be really helpful. Here are some of the main themes, on which I’d be grateful to hear thoughts. (These are here condensed and presented without much argument; for further info, obviously, see the paper.)

Thesis 1: As in previous work, I’m concerned with defending a distinction between what there is and what there really is. Following Sider, in order to resist neo-Carnapianism we should insist that there’s a unique most natural existential quantifier: one that carves the world along its quantificational joints. But, there’s no need to say that the ordinary quantifiers of English are this natural quantifier. Naturalness is a reference magnet, to be sure, but it can be trumped by use. But we can introduce a quantifier (‘there really is . . .’) stipulated to be the most natural quantifier. As long as you’re happy with the naturalness talk in the first place, there’s now no mystery in saying that what there is might come apart from what there really is.

Thesis 2: I defend a two-dimensionalist approach to sentences like ‘there is a table’. Considering the universalist world as actual, this sentence requires a table as a truthmaker, and so considering other worlds as counterfactual, we should only judge the sentence to be true at those worlds if they contain certain complex objects, namely tables. But considering the nihilist world as actual, the charitable thing to say is not that that sentence is false but that it requires for its truth only the existence of simples arranged table-wise, and so considering other worlds as counterfactual, we should judge the sentence to be true at a world iff it contains simples arranged table-wise. An attractive consequence is this: assuming (which I hope is the case) that the nihilist world is actual, we have a nice explanation for what many people think is a necessary truth, the necessity of which otherwise looks mysterious, namely: if there are simples arranged table-wise then there is a table.

Thesis 3: It’s right to take Moorean truths about what there is as inviolable. What’s wrong, however, is to read the ontology straightforwardly off of them. The truth of ‘Here is a hand’ is indeed on a stronger footing than any conjunction of premises that entails its falsity. But that doesn’t mean that, e.g., compositional nihilism is false. Compositional nihilism, properly understood, is the claim that no complex objects really exist, and that is compatible with the claim that there are complex objects like hands. The proper methodology is to ask what are needed as the ontological grounds for the Moorean truths. There are no Moorean truths about what there really is.

Thesis 4: The problem of the many is easy. There’s a unique cat on the mat. But asking which collection of particles is the cat, is a bad question. There isn’t really a cat. You can only ask, which collection of particles grounds the fact that there is a cat? Answer: all of them (i.e. all the collections which the universalist thinks are candidates for being the cat). But that doesn’t mean that there are many cats, of course – the one sentence can have multiple grounds.

Thesis 5: Since the ontological commitments of a sentence are its ontological grounds, it’s an open possibility that there are true sentences that lack ontological grounds and hence carry no commitments. I suggest that the truths of mathematics are like this. It’s true that there is a prime number between 8 and 12; but it’s a mistake to think that this is ontologically committing to numbers. (And no ‘paraphrase’ of the sentence into something not quantifying over numbers is necessary to say this.) Mathematical claims are trivial in the sense that they make no demands, a fortiori no ontological demands, on the world. (Cf. what I say here to what Agustin Rayo says in his defence of mathematical trivialism in this excellent paper.)

Thesis 6: Actually not a thesis. I tentatively speculate that one could reduce necessity in the following way: p is necessary iff p lacks an ontological ground. Obviously, not everyone’s going to think this is extensionally adequate, since some think contingent negative existentials lack a ground, and others think everything has a ground, including necessary truths. But I think it looks quite hopeful, and would like to hear whether or not anyone else does.

In other news, Elizabeth and my paper (“Elizabeth and my” – is that right? It sounds terrible, but I can’t think what else it should be.) on the open future has been accepted by Phil Studies. But we’d still appreciate any comments on it, as it’s an issue we’re hopefully going to keep working on.


Geoff said...

Ross - I think the paper is great. Very clearly written. I think that talk of finding naturalness and carving nature at its joints as the task of ontology does more for you than talk of 'ontologise'. I find your view much more plausible when expressed as you have done in this paper.

I do have this feeling that your acceptance of some aspects of neo-carnapianism feels a bit like you are trying to have your cake and eat it, but i'm not sure right now how to argue for it so i'll leave it to the side.

(But:Is it really possible to accept the spirit of neo-carnapainism whilst holding that there is still a deeper 'proper' ontological question about what really exists? If I understand you right, you want to say that real ontology is about working out how nature is carved at its natural joints – and that will tell us what really exists. But doesn't this mistake ontology for particle physics? Why can't the full blown neo-carnapian say that all you are doing is showing a preference for the ontological framework of fundamental particle physics.)

My bigger worry is that the particle physics world view that you favour as the most natural is not a simple or as natural as might be hoped. For example, if electrons are probability clouds, are they simples? What if the best representation of what an electron is is as a wave function. Does this mean there really are wave functions? But then these look more like mathematical objects than the kind of simples you want in your ontology. Can I say: there aren't really electrons, just wave functions?

Perhaps you say that the wave functions (or probability clouds, or what ever) are just the way that we represent the simples and, since we shouldn't mistake our representation for an ontology of that which is represented, we don't have to worry about accepting wave functions.

But then it seems like our ontology will always be of things 'we know not what' - our fundamental ontology will always be allusive. Every attempt to describe it in language or science will not tell us what really exists – so what really exists will always be some unknown ground for all our scientific claims – which sounds a bit like Locke's substratum.

Here's another thought. I think you are being a bit unfair to Quine. Surely Quine took himself to be asking 'what really is there' - and the answer 'everything' refers to everything that there really is. All the other things don't really exist. Even if we say that they do. He wasn't asking 'what does our language say there is' because then he wouldn't have bothered with all the paraphrase stuff. Perhaps you don't agree with his methods of getting to what really exists, but you can't deny that he was asking the genuine ontological question. (perhaps this isn't a substantial point against you)

Ok, I know these ramblings do not constitute fully supported arguments, so I don't expect a detailed response, but perhaps you can get the gist of what I mean.

Ross Cameron said...

Thanks Geoff. It's certainly right that the neo-Carnapian isn't going to be happy with what I say: they're not going to accept that there's a unique most natural meaning for the quantifier - so yeah, they're just going to think I'm privileging a certain description of the facts, that isn't metaphysically special. I don't aim to be capturing everything the neo-Carnapian wants to say: I just want to be able to buy into enough neo-Carnapianism to say that we can be assured that Moorean truths about what there is are true - without taking this to refute apparently revisionary metaphysics.

I think you're reading into the paper a deference for physics that I don't intend. I say I favour an ontology of simple substances, but there's no commitment there that these need to be what the physicists tell us are the physical simples. I favour an ontology of simples, because I don't want mereological notions among my fundamental ideology. But the simples, as far as I'm concerned, might be things like you and I. This isn't to say we don't have parts, though: it's to say that we don't *really* have parts; so fundamentally there might not be such things as our arms and legs, but we make it true that there are such things. Now, I'm not saying that's what is the case - but it's compatible with everything I say. Certainly, I don't think we can just read fundamental ontology off of physics - whatever the relationship there is, I think it'll be a complicated one.

On Quine: I'm happy if the debate between us reduces to one about how ot go about discovering what there really is. It's really the methodological lesson about how to do ontology that I'm interested in.

Geoff said...

Thanks for the reply Ross. Now that you put it that way, I clearly was just assuiming a deference for physics. My mind just jumped from simples, to an atomic world view, to modern physics. With that dropped, I'll have another look over the paper.

Luigi Speranza said...


I would suggest you take a good look at

Warnock, G. J. "Metaphysics in logic" by good ol' Leeds-born philosopher. He is so seldom quoted by English and Argentine philosophers (never mind Italian) that it hurts! But it's a GEM! I discovered it as repr. in a collection of "Essays in Analysis" ed. by Flew.

It _IS_ a gem: it's all about "there is". And without much Quinean corruption about it!

---- I would suggest we go artlessly sexist with your 'really', really. It is, as Austin would say, really, 'a trouser word', no? (His example of the 'real duck' in Sense and Sensibilia). I love 'real', though, because I love trouser words, on the whole.

----- I have written extensively, elsewhere on the "there" in "there is". It has nothing to do with "there" and we MAY want to go _there_. There's no such thing in any other language I know! It's 'c'e' in Italian, 'es gibt' in German, 'il y a' in French, 'hay' in Spanish. Nothing to write Quine about!

--- Anyway, if you find the Warnock paper easily enough and can comment, either here or in my blog (The Grice Club) more than welcome.


J. L. Speranza

--- I should say that I'm working with R. B. Jones -- he is an expert on Carnap, and I'm retrievin various uses of 'palaeo-Carnapian', and it was your use of 'neo-Carnapian' that brought me here. I see you need Hirsch vs. Sider, etc. Jones is such a Carnap fanatic that he has created a CarnapCorner.blogspot for our edification, so enjoy!