Tuesday, February 24, 2009

An Argument against Presentism

Presentism is the thesis that no non-present objects. I was just thinking about this simple argument against presentism and I was wondering what all of you might think of it.

1. The proposition that 2+2=4 is not ever anywhere.
2. for anything whatsoever, if that thing is ever present, then it is somewhere at sometime.
3. So, the proposition that 2+2=4 is not ever present.

(1) seems intuitive. It does not seems as though we would be able to find a proposition if we just looked hard enough. Even if we could check every spatial region at every time, we would not be able to find the proposition that 2+2=4. but, if that proposition did at some time exist at some region, then it seems like we would be able to find it if we just looked.

Premise (2) is true because of the manifold nature of space-time. Given that space is three dimensional, no object can be some distance from me along one dimension without also being some distance from me along the other two dimensions (perhaps that distance is a zero distance). This is because the regions of one dimension are just composed of the regions of another dimension. So too, since time is putatively just composed of blocks of space, anything that is ever present must also at some time be spatial. (3) seems to follow from (1) (though the validity of the inference might be in question, there is no question that the inverence is cogent)

4. If the proposition that 2+2=4 is not ever present, then it is not present.
5. So, the proposition that 2+2=4 is not present.

Premise (4) seems very plausible. If something is not ever present, then it simply is not present. If something is present, then it is present at some time (namely the present). (5) follows from (3) and (4).

6. If the proposition that 2+2=4 is not present, then presentism is false.
7. So, presentism is false.

(6) seems obviously true. If presentism is the thesis that everything is present, then if something is not present, then presentism is false. So, if the proposition that 2+2=4 is not present, then presentism is false. (7) follows validly from (5) and (6).

I see several responses that someone might make to this argument. Some of the responses would probably be more widely accepted than others. Someone might, for example, reject (6) on the grounds that propositions do not fall within the scope of the quantifier 'everything'. This view might be most acceptable to non-serious presentists. such presentists might already accept that Socrates stands in relations to me and even that 'Socrates' refers. However, they reject that Socrates refers to anything that falls within the scope of 'exists' or 'everything'. If we are willing to accept the non-serios presentists position, then it shouldn't be too difficult to accept that the proposition that 2+2=4 also stands in relations, that 'the proposition that 2+2=4' refers but that that referent fails to fall within the scope of 'exists' and 'everything'. Moreover, this view might actually be held by Graham Priest. I think this is my preferred response to the argument (though I do have worreis about how to analyze the definite description), but I think this response would not be widely accepted.

I think that some presentists would deny (1). They might say that I am confusing the relation of existing-at with the relation of being located-at. To exist at a region is merely to be in the domain of quanfification for a region. To be located at a region is to have some kind of presence at that region. For example, I am not located at my apartment right now. However, I am within the domain of quanfication for my apartment. Hence, I exist-at my apartment without being located there.

I think that this way of rejecting (1) is mistaken. I am not sure I completely understand 'exists-at' but insofar as I understand it, it seems obvious that it implies a presence of some kind. If I exist-at my apartment, then I better be in my apartment. My opponent might push further by saying that I am only introducing further confusions. I am confusing 'exists-in' and 'exists-at' or maybe I am confusing 'exists with respect to' with 'exists-at'. But, I think it is my opponent who is introducing confusions. In the argument above, I refrained from using any phrase like 'exists-at'. So, it is not enought to simply say that I am confusing 'exists-at' with some other relation. My opponenent needs to say something about how this relates to premise (1).

My guess is that someone who claims that I am confusing 'exists-at' with 'exists-in' or 'exists with respect to' has some kind of analysis of 'The F is not ever anywhere' in mind; she has an analysis that employs 'exists-at' or 'exists with respect to' or whatever. But, any analysis of 'The F is not ever anywhere' that implies that 'The proposition that 2+2=4 is not every anywhere' expresses a falsehood has a singnificant strike against it. Such an analysis better do a lot of good theoretical work to account for such a counterintuitive consequence. I don't know for sure, but my guess is that there are not such strong theoretical benefits to the proposed analyses.

So, if (1) and (6) are okay, then we are left with (2) and (4). I can't think of any theorist who denies (2) or (4) and I can't think of a plausible metaphysical view that implies the denial of (2) or (4). If any of you can, I'd like to hear about it. In any case, it seems to me that a view that denies (2) or (4) will have something interesting to say about the particular quantifiers 'ever', 'sometime' and 'somewhere'. I'd like to hear what such a view has to say.

20 Comments:

Blogger bradley said...

First and most importantly, I think most presentists think that presentism is a thesis about concrete objects.

Second, here's a way to reject (4). As I interpret your claim, you're saying that for all x, if there's no time at which x is present, then x is not present simpliciter. But that might be false. What if x is present at a fusion of instants, but not at any one instant? If that can be the case, then perhaps 2+2=4 is present at the fusion of every instant in time.

10:16 AM  
Blogger Andrew Bailey said...

I think Brad's first point is right on the money.

And the presentist has another plausible way to restrict her theory so as to avoid (6), viz., to things in time. Presentism, then would be the thesis that all things in time are present. (I assume here that propositions aren't in time, whatever that might mean).

Brad's second objection looks inconsistent with presentism, though. For if presentism is true, there aren't a plurality of instants. So how could [2+2=4] be present at the fusion of such?

10:43 AM  
Blogger Alex said...

Brad's first point is exactly right, I think. I see no reason whatsoever why presentists ought to accept (6), nor do I see why such a presentist would be "non-serious".

I'm not convinced by his second point, however. Presumably the argument that Joshua adduces in support of (1) would be an argument against the thought that propositions are present at (maximal?) fusions of instants.

10:47 AM  
Blogger bradley said...

Perhaps I chose a bad "way out" for the presentist. But I maintain that there might be a way of getting around the claim: for all x, if there's no time at which x is present, then x is not present simpliciter.

Maybe not, though. Luckily my first point stands. =)

10:51 AM  
Blogger Andrew Bailey said...

Nice hand-waving, Brad. Did you have a particular way in mind?

11:00 AM  
Blogger Neal Tognazzini said...

I've heard presentism formulated before (though I forget by whom) as the thesis that there exists nothing at any temporal distance from the present (or something along these lines). If this is how we should formulate presentism, the problem of propositions that Joshua raises would not arise, and we wouldn't have to just stipulate that the thesis only applies to concrete objects.

11:54 AM  
Blogger Andrew Bailey said...

Neal, that is Crisp's way of putting it (OSM, Vol. 1). And I agree. It, too, is a plausible way of rejecting (6).

12:12 PM  
Blogger Andrew Bailey said...

Er, Crisp's entry in Oxford Handbook of Metaphysics, that should be. Not OSM.

12:14 PM  
Blogger bradley said...

Technically, Crisp's formulation is that nothing exists at a temporal distance from anything else. Close, but worth distinguishing.

12:20 PM  
Blogger Neal Tognazzini said...

Thanks, Biola guys. Crisp came out to meet with a philosophy of time workshop Michael Nelson was running a couple of years ago...that must be where I heard it.

12:24 PM  
Blogger Joshua said...

Hello all,

I'm very surprised about how many comments there are on my post! Thanks to all of you for your responses. I wanted to reply to a few things that have been said.

The thesis that I was thinking of when I wrote the post might be called Naive Presentism and is formulated as follows:

Naive Presentism: There are no non-present objects.

It is clear that if we interpret 'presentism' as Naive Presentism, then premise (6) is true. However, it looks like everyone is suggesting various ways of interpreting 'presentism' on which (6) is false. Here are two of the suggested interpretations of 'presentism':

Concrete Presentism: There are no non-present concrete objects.

Temporal Presentism: There are no non-present temporal objects.

Each of these theses is plausible and I am not sure which thesis various presentists intended to endorse. There are interesting relationships, though, between these various theses. It is clear that Naïve Presentism entails both Concrete Presentism and Temporal Presentism. Moreover, if it is necessary that everything is concrete, then Concrete presentism entails Naïve Presentism. Similarly, if it is necessary that everything is temporal, then Temporal Presentism entails Naïve Presentism. What this means is that any theorist who wants to interpret ‘presentism’ in the argument as either Concrete Presentism or Temporal Presentism while also rejecting premise (6) in the argument must either reject the thesis that everything is concrete or the thesis that everything is temporal. But, this shouldn’t be too surprising of a response. After all, any theorist who is Platonist enough to accept that the first premise should reject the theses that everything is concrete and that everything is temporal.

As I mentioned, I am not sure which thesis various presentists intended to endorse. However, it is clear that Concrete Presentism and Temporal Presentism are consistent with the claim that Socrates exists. Such a theorist would have to endorse that Socrates changed from being temporal or concrete to being either non-temporal or non-concrete. So, if a presentist wants to hold on to the intuition that Socrates just does not exist in virtue of the fact that no present things is identical to Socrates, then He’ll also have to say something more; he’ll have to say that nothing can change from being concrete or temporal to being non-concrete or non-temporal. Perhaps this sort of view is exactly what many presentists had in mind.

2:06 PM  
Blogger Andrew Bailey said...

"So, if a presentist wants to hold on to the intuition that Socrates just does not exist in virtue of the fact that no present things is identical to Socrates, then He’ll also have to say something more; he’ll have to say that nothing can change from being concrete or temporal to being non-concrete or non-temporal."
Why? Won't the weaker thesis that 'nothing in fact changes from being concrete or temporal to being non-concrete or non-temporal' do the job? Only those who endorse the necessity of presentism seem committed to the stronger modal claim that nothing *could* switch statuses across the concrete/abstract or temporal/non-temporal divide.

2:13 PM  
Blogger Joshua said...

Neal,

Thanks for mentioning Crisp's view. We can formulate Crisp's view as follows:

Crispian Presentism: There is nothing that is any temporal distance from the present.

As I mentioned in my last comment, many of the suggestions seem involve presenting various interpretations of 'presentism' on which (6) is false. This is another such suggestion.

I do find Crispian Presentism to be a bit strange. I suppose the following is possible:

(POS) There are exactly two disconnected times and there are exactly two objects, one at each time.

If this is a genuine possibility, then it is a possibility in which Crispian Presentism is true. After all, the two objects bare no temporal relations to one another. The following would express a true proposition at either of those times:

S1 "nothing is any temporal distance from the present".

However, the following would also express a truth at either of those disconnected times:

S2: "There is a non-present object".

I am not sure what most presentists think, but I worry that they would not want to say that both of these express truths. I also worry that they would not want to say that (POS) is true and presentism is true. But, that seems that a Crispian Presentist is committed to both of these consequences.

2:20 PM  
Blogger Joshua said...

Andrew,

you might be right. Perhaps a presentist does not need endorse that nothing can change from being concrete to being non-concrete. Perhaps a presentist need only endorse that nothing does change from being concrete to being non-concrete.

I have one worry. If one thinks that Socrates does not exist in virtue of the fact that no present thing is identical to Socrates, then presumably this entails some modalized claim. It was not wide open metaphysical possibility that I was thinking about when I made my earlier claim, but rather some modality that might be grounded by whatever grounds the in virtue of claim.

However, I don't know much about in virtue of relations. Perhaps Alex knows something about the relationship between various in virtue of claims and various restricted modalities.

2:34 PM  
Blogger Andrew Bailey said...

Joshua,

Thanks for the interesting post, by the way. It began an interesting discussion in Malloy Hall this afternoon. =)

You write: "If one thinks that Socrates does not exist in virtue of the fact that no present thing is identical to Socrates..."

I'm not sure why one should think this. Quine taught us that x exists iff something is x. I read the 'is' there as identity. So to say that Socrates exists just is to say that something is Socrates. It is to say, that is, that something is identical to Socrates.

Argument:

1. The in virtue of relation is anti-reflexive (nothing is so in virtue of itself).

2. The fact that Socrates exists is the same as the fact that something is Socrates.

3. Therefore, the fact that Socrates exists does not obtain in virtue of the fact that something is identical to Socrates.
-Andrew

2:40 PM  
Blogger Andrew Bailey said...

Whoopse, I wasn't done there!

(Unstated Assumption: if the fact that Socrates exists is the same as the fact that something is Socrates, then the fact that Socrates doesn't exist is the same as the fact that nothing is Socrates).

(Unstated Conclusion: therefore, the fact that Socrates doesn't exist does not obtain in virtue of the fact that nothing is identical to Socrates.)

2:43 PM  
Blogger bradley said...

Josh suggests:

(POS) There are exactly two disconnected times and there are exactly two objects, one at each time.

What do you mean when you quantify over times? Tom considers them to be ersatz entities of some sort.

Further, you can describe this world from here, but within that world, there is no time at which it is the case that both objects exist. It is the case for the earlier object that WILL(another object exists) and for the later object WAS(another object exists), but for neither is it the case that another object exists.

So, the Crispian presentist denies S2.

5:44 PM  
Blogger Joshua said...

Bradley,

I'm sorry, I should have been a bit more explicit. When I said that it is possible for there to be two disconnected times, I meant two temporally disconnected times. That is, two times that stand in no temporal relations to one another.

some people think that you can have disconnected space-times. That is, two or more space-time regions that stand in no spatiotemporal relations to one another. If that is really possible, then we can have two temporally disconnected times as well. Of course, if there are two temporally disconnected times, then neither will be earlier or later than the other. Neither will be in the past of the other. However, each will be present with respect to itself. On this view, if O1 is at T1 and O2 is at T2, then with respect to T1, there are no objects any temporal distance from T1. This is because O1 is at T1 and so is not any temporal distance from T1 and O2 is at a temporal disconnected time and as a consequence is not any temporal distance from T1 either.

8:11 AM  
Blogger Joshua said...

Andrew Bailey,

Thanks for your argument against the claim that Socrates does not exist in virtue of the fact that nothing is identical to Socrates. It sounds pretty good. I take it that since presentists endorses that something exists iff it presently exists, they will be able to argue for the further conclusion that the following is false: Socrates does not exist in virtue of the fact that no present thing is identical to Socrates.

Joshua

8:18 AM  
Blogger bradley said...

Josh ~

I suppose the Crispian will have to deny the possibility of cases with completely disconnected space-times. (Lewis must do this, too, right?) But I don't consider it too much of a cost, since I certainly have a hard time conceiving of such worlds.

3:01 PM  

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