OrangePhilosophy

It seems to me that the right thing for a three-dimensionalist to say about time travel cases is that someone is wholly present in two places at the same time (in external time, though not at the same time in personal time). With time travel you can relativize to personal time, but you can't do that with the cases I'm guessing you have in mind, e.g. fission leading to a bilocated person. What you have to do with those is relativize to places rather than times.

I don't like this bent-at-t1 and bent-at-t2 stuff. I don't think that's what a three-dimensionalist should say. At t1 it's bent, and at t2 it's straight, but that's because it has-at-t1 the property of bentness-simpliciter, and it has-at-t2 the property of straightness-simpliciter. It's not because it has-simpliciter bentness-at-t1 and it also has-simpliciter straightness-at-t2. The property itself is had intrinsically, but nothing in time has properties irrespective of times.

I was thinking neither of time travel nor of fission leading to a bilocated person, but good old ordinary persistence. Three-dimensionalists think that when something persists through two times, it is wholly located at each of those two times. That's what I was thinking of, and that's what may be considered as a violation of Leibniz' Law already.

Notice that, in dealing with this problem, the relationalizing strategy you prefer is no better off than the strategy you don't like.

The object has at t1 the property of being located at t1 and has at t2 the property of being located at t2.

This explication doesn't remove the contradiction, if there was one.

I was reading 'location' as spatial location.

I think my solution does work here. I have the property of having-at-t1 the temporal location of t1 and the property of having-at-t2 the temporal location of t2. That's not a contradiction, and it does distinguish the two properties as being had in different ways. Not only that, but it preserves the sense of intrinsicness to the property that Haslanger's solution doesn't preserve.

I'm not sure what more you want in a solution. I think you want the statement to say more than that at a certain time you're at that time, as if a statement that you're at a time is supposed to say more than that, but a statement about where you are in time doesn't say any more than that, so a more metaphysically accurate paraphrase of it need not say any more either.

I am afraid seeing the problem requires one to (for the moment anyway) not be a three-dimensionalist. (This is why the three-dimensionalist can insist that you cannot describe this problem without begging the question against her.)

"I have the property of having-at-t1 the temporal location of t1 and the property of having-at-t2 the temporal location of t2. That's not a contradiction, and it does distinguish the two properties as being had in different ways."

When can something have the location t1 but at t1? When you insert 'having-at-t2' are you genuinely adding any new qualification that can remove a contradiction?

(There is an eternal or tenseless sense of 'have' on which you can have a temporal location t at times other than t--perhaps at all times, or at least at all times at which you exist. But since being located at t1 and being located at t2 cannot be distinguished from that eternal standpoint, we will ignore that tenseless sense of 'have' and give the answer in the temporal sense.)

The insertions you make are not informative. Therefore, if the pair of properties having location t1 and having location t2 contradict, then so does the pair having-at-t1 the temporal location of t1 and having-at-t2 the temporal location of t2.

What do I hope for in a solution? I don't think I expect a solution in the sense of a paraphrase. (I think that the only paraphrases that could do the trick would have to be four-dimensionalist.) Rather, I am trying to understand the three-dimensionalist intuition that something can be at two times without contradiction.

I'm still not sure I see what the problem is. The dialectic informally (i.e. in a way neutral between Haslanger's way of doing it and my way of doing it) goes like this:

The 3Der says my finger is straight. Then the 3Der says the same finger is bent. The 4Der says, "Aha -- but it can't be both straight and bent." The 3Der responds that it can't be both straight and bent at the same time, but it can be straight at one time and bent at another. You now step in and say that it can't be at both t1 and t2, and the 3Der says the same thing. It can't be at t1 and t2 at the same time, but it can be at both at different times, namely the two times specified, t1 and t2.

How is that not informative? It's informative in the sense that it points out that the question assumes something that's simply not true. For the question to make sense, it would have to be possible to be at two times at the same time. That might lead to a contradiction. But there shouldn't be a contradiction with being at two times at different times.

If I asked: How can an object be in two spatial locations (ignoring time travel and fission) s1 and s2? You would not respond by saying
"Easy. It would have to be at s1 at s1 and at s2 at s2."
This would be an absurd response. Consider this example: I can be on the first floor and on the second floor because I am on the first floor only on the first floor and on the second floor only on the second floor. I am never on both floors at the same floor.

Let's call it "indexing to the aspect under consideration" when one gives does the following. One is asked to explain how it is not a contradiction for object o to have F and to have G, when F and G are incompatible properties under the same determinable. One responds by saying that the object is F-wise F and G-wise G. One admits that being F-wise F and F-wise G would indeed contradict but explains that that's not what's going on.

Now, indexing to the aspect under consideration is not an example of good reasoning. It does not yield a satisfactory explanation. Perhaps it's worth examining exactly why this is so, but I’m not ready to do it at this moment. The only thing I can note here is that we never do it. That is, I have never seen another example of this mistake before.

What I hope to convince you is this. I agree that in the first floor/second floor case you can show the absence of a contradiction by indexing to times. That would not be an example of indexing to the aspect under consideration. However, this does not mean that indexing to times is the right answer for any pair of contradictory properties. In particular, if the distinct locations allegedly had by the object are temporal locations, then the indexing to times is in fact indexing to the aspect under consideration.

Moreover, (correct me if I'm wrong here, but I thought that) spatial locations do not exist independently of temporal ones and vice versa, and we are either (illegitimately) abstracting away or being sloppy when we speak of a time t without a spatial coordinate or a spatial location s without a temporal coordinate. If this is true, and we are only to speak of spatiotemporal locations (in which space-like and time-like coordinates are built) then there is even less hope for analogous indexing to spatiotemporal locations strategy. Let l1, l2,...ln be variables that range over spatiotemporal locations. My question then becomes the following. How does an object occupy two distinct locations l1 and l2 (without fission or time travel)? Under the view we are examining, the object would have to be at l1 at l1, and at l2 at l2. You can then go on to explicate that, either by adding an index to the locational property or by adding an index to the inherence of the property. In either case you will be indexing to the aspect under consideration.

I'm pretty confused about this dialectic. The 3d-er agrees with Lewis that it is bad for the following conjunction to be true:

(1) 'object o is straight and bent'.

But fixes it up by either relativizing to times:

(2) 'o is straight (at t) and bent (at t' and ~(t'=t)'

(Or, following Jeremy's suggestion, we can refuse to allow the conjunction by demanding evaluation of sentences at times, even though we refuse to treat the time as an argument of the predicate).

So Irem asks: isn't being at t1 incompatible with being at t2? If that is right, this should sound as bad as (1):

(3) o is at t1 and at t2.

But does anyone get the sense that (3) sounds contradictory in the way that (1) does? I have to confess that I don't feel any implict pull to being at t1 is incompatible with being at t2. Maybe I'm just agreeing with Jeremy (I'm not sure I fully understood what he was saying above).

I agree with Adam that the implicit pull to regard (3) as a contradiction is missing. But it should not be a matter of implicits pulls and pushes whether we will regard propositions to be contradictory. Why should we trust this comfortable feeling we have about (3) being all right? In form and content it is little different from (1), or
(1a) o is on the first floor and on the second floor.

Furthermore, if there really are no such isolated things as spaces and times but only spacetime regions, then what we are supposed to be evaluating is something like
(4) o is at l1 and l2.
With likes of (4), we don't have strong feelings one way or other, and even if (3) were okay, there is no reason to think that (4) is likewise okay.

It's worse. It's:

o is wholly at l1 and wholly l2.

It's not a contradiction yet, though. You need a further principle that says that something can't be wholly occupying two different spacetime regions. That's what a 3Der will insist to be false, which is why there's this sneaking suspicion that the argument is question-begging.

Suppose I agree that something can occupy two distinct temporal locations. When it comes to the tenability of (4), the 3Der has to insist that spacetime regions (the things l's range over) are more like temporal locations (the things t's range over) and less like spatial locations (the things s's range over). We do not even have any feelings to ground this judgment, however.

Hey Guys,

I don't know what charges like 'question begging' amount to. I thought that we have the follwoing way of proceeding (on teh model of temporary intrinsics argument from Lewis):

1) We KNOW that the following are contradictory: I am standing and sitting.

2) 3d-ism (some forms) are committed to the truth of 'I am standing and I am sitting'

3) Therefore 3dism is committed to the truth of contradictory sentences.

(I don't know why I did it metalinguistically but I assume that disquoting is harmless here). Anyhow, what *I* was pointing out is that (P1) is plausible in the case of standing and sitting but less plausible (intuitively) in the case of 'exists at t1' and 'exists at t2'.

Now, we can put aside intuitons and feelings and so forth, but then why don't we put them aside in the case of 'standing' and 'sitting' as well? Why shouldn't we say that it is just false that something can't stand and sit, or at least that our feeing our irrelevant?

It well might be that the comfortableness we feel with 'wholly existing at t1 and wholly existing at t2' is a reflection of our implicit commitment to 3dism.

Now we're getting somewhere. Thank you Adam for bringing it together nicely. Hence the conditional claim I began with, "If there is any problem with an object's having contradictory properties without violating Leibniz' Law, then there should equally be a problem about an object's having two contradictory locations."

Wait, Irem, now I'm sort of confused. LL doesn't tell you which properties are contradictory: (actually, it doesn't even say that an object can't have a property P and some contradictory property ~P, at least not on its own). My point was that while it is extremely plausible that nothing can instantiate a sitting and a standing event (at the same time), it didn't seem implausible to me that something could wholly participate in an event at t1 AND wholly participate in an event at t2 (where 'wholly participate' means that it is wholly located where it's role in the event is located').

We should be careful here, especially when it comes to 'contradictory' properties: it is very difficult to tell off hand what properties and object can simultaneously have and which it can't. Newton seemed to believe, for example, that there are extended simples: but those are things that can (indeed, must) wholly exist in two different places at the same time. Its not clear that Newton was wrong on a priori grounds.