Tuesday, June 14, 2011

Open future (again)

Elizabeth and I have posted a draft of a new paper on the open future: available here. Comments welcome!

9 comments:

Rich Woodward said...

Hi guys,

Cool paper. One little thing: I was wondering what you think about sentences like "Robbie will be involved in a space battle".

Spotting the indeterminacy in persistence conditions you contemplate, this seems like it could be case of indeterminacy that's overdetermined in some way: perhaps it's indeterminate because the it's presently open whether there will be a space battle and indeterminate because it's of the indeterminacy surrounding the question of whether Robbie persists.

But doesn't your account then imply that the future is not open with respect to "Robbie will be involved in a space battle" because even though "Robbie will be involved in a space battle" expresses (at t) a proposition that (at t) is metaphysically indeterminate, it won't be the case that "Robbie will be involved in a space battle" was determinately true or determinately false because of the indeterminacy inducing issues of persistence?

If that's the result, are you happy with it? It seems a bit weird to me but I can't quite put my finger on what's bugging me about it. I guess part of it is something like the thought that if the future is open wrt to S then the future should be open wrt to any sentence S' which cannot be true unless S is true.

Rich Woodward said...

Also, I feel compelled to say something about the irrelevance objection you draw from Jubien. As stated, the Jubien objection a mess: the totality of logical space isn't a bunch of parralel contingencies: logical space *had* to be the way it is, and at best Jubien has got himself in a muddle by confusing ordinary modal claims and extraordinary ones.

Relatedly, you write: "Lewis’s reality doesn’t look modal – it just looks like actuality is a lot more complicated than we thought." Alot turns on what you mean by "actuality" and "reality" here! And when you come to the Branching picture, and say "the B-theorist brancher’s future doesn’t look open – how things will be just looks a lot more complicated than we thought" it's noticeable that this *isn't* the analogous point to the one you make wrt Lewis. The analogous point would be "the Brancher's reality doesn't look tensed - it just looks like actuality is alot more complication than we might have though". But the Brancher (at this point) is a B-theorist and it's no wonder that reality doesn't look tensed just as it isn't any wonder that reality doesn't look modal for Lewis. (And then there is an issue about what "actuality" means within the branching picture.) I know you were only using the stuff to "pin down intuitions" but still.

Ross Cameron said...

Yeah, 'Robbie will be involved in a SB' will not be a case of the open future being open even though 'A person made from the Robbie-matter will be involved in a SB' might be. It's weird, but I think livable with. Although we could make the 'we're not giving an analysis' plea here, and say that the proposal gets the paradigm cases right and cases like this where the indeterminacy is overdetermined are just weird.

On Jubien. I think you're being a bit unfair to him. Of course, Lewis has the resourced to defend himself against the charge. It's not true according to the theory that the worlds are a bunch of parallel contingencies, or that actuality is just a lot bigger than we think. But I think the charitable interpretation of the objection isn't that it's trying to expose a flaw in the theory (in the way that, e.g., Josh Parsons is when he claims that it leads to the T axiom failing). The objection is trying to pinpoint a source of dissatisfaction people have. I don't think you can ease those worried by giving a theory of advanced modalizing, although you can certainly thereby show that the Lewisian shouldn't agree with you on your description of how they think reality is. Cf. A-theorists complaining that the B-theoretic universe is 'static'. Giving a B-theoretic account of passage isn't going to ease their worry, but what it does do is allow the B-theorist themselves to reject the charge.

Rich Woodward said...

With respect to the charitable interpretation of the Jubien complaint about Lewis, I'm genuinely not sure what the source of the dissatisfaction is supposed to be. At best it seems to rely on a tendentious description of the metaphysical picture.

Don't get me wrong: I think that there are genuine concerns around here, but I'm not sure Jubien is getting at them and I worry that saying "it's just pinning down a source of dissatisfaction" isn't helpful unless you can pinpoint the dissatisfaction, and ultimately I think the complaint gives way to the line of questioning someone like Divers might pursue: if *that* is what modality consists in, why do we bother about it in the first place?

Ross Cameron said...

I agree the Divers question is a good one, just as it is for genuine temporal passage, et al. But I tend to think that it's legitimate to explore what the best metaphysics is if you want a fundamentally modal/tensed world even if you haven't managed to convince the skeptic that the world is fundamentally modal/tensed.

Rich Woodward said...

I never said that wasn't legitimate!

Ross Cameron said...

No, I know - sorry, that might not have come out right! What I mean is: I think there's a legitimate project that starts from the assumption that the modal irrelevance objection or the 'that's static!' objection to modal realism/B-theory is on to something, and explores the best metaphysics that captures that. Sooner or later, that person faces the challenge: if you're so strict about what it takes for reality to be modal/temporal, what's the reason for thinking it IS? And maybe she has no better answer than: intuition. It's interesting if that is so, and I would hold it to be a mark against the theory, but not an insurmountable one. I think if that's the role the Jubien objection is playing - which is how I take it - then it's not a bad objection. (I think the best version of the objection is actually Williamson's, but it didn't suit our dialectic as well!)

jlewispi said...

can someone please summarize in one or two sentences what an 'Open Future' is, and why anyone would want to care about it outside of this blog?

Ross Cameron said...

The future is open if there's more than one way it could turn out. So for some claim concerning how things will be, the future might turn out like that, or it might not. People care about it because it's interesting.