Saturday, April 13, 2019
Vallicella on the truthmaker objection against presentism
Among the many ideas defended in Relativity, time travel, the experience of time, and other issues in the philosophy of time are treated along the way, and what I say about those topics is crucial to my defense of presentism. (See pp. 233-303.) My buddy to my response in the book to the “truthmaker objection” against presentism. Let’s consider Bill’s misgivings. is the A-theory of time, and presentism in particular.
Presentism is the thesis that only the present exists, and that past and future events and objects do not. To be more precise, it is the thesis that in the temporal realm, only present objects and events exist. (For one could also hold – as I do, though other presentists might not – that in addition to what exists in time, there is what exists in an or timeless way and what exists in an way.)
Among the rivals of presentism is the “eternalist” view that past and future objects and events are as real as present ones. There is also the “growing block” view, according to which past objects and events are as real as present ones, though future objects and events are not.
The truthmaker objection essentially goes like this. If a statement is true, then there must be something that makes it true. For example, if it is true that the cat is on the mat, that must be because there really exists some cat on some particular mat. Now, consider the statement that Julius Caesar was assassinated on the Ides of March. This is true, so there must be some truthmaker that makes it true. But it makes reference to a past event, and presentism holds that past events no longer exist. So how can there be a truthmaker for this statement?
There has been a lot of heavy going about this objection in the literature, but I don’t think it is at all impressive. That is not because I would deny the “truthmaker principle.” On the contrary, I think it is not only true, but trivially so – so trivial that I don’t know that we really need a momentous label like “truthmaker principle,” which makes it sound more substantive and interesting than it really is.
Yes, a statement is true only if there is something that makes it true. But that doesn’t tell us very much, because there are so many kinds of thing that might make a statement true. The statement that the cat is on the mat is true because of facts about the existence of and relationship between two spatiotemporal objects. But different sorts of statements will have very different sorts of “truthmakers.” For example, the statement that Iron Man is really Tony Stark is true. But that is not because of facts similar to those that make it true that the cat is on the mat, because unlike cats and mats, Tony Stark is a fictional character. So, what makes that sort of statement true has to do with the way certain people happened to write certain works of fiction.
Or take the statement that you can apologize to someone by sincerely uttering the words “I apologize.” What makes that statement true is not any sort of spatial relationship between physical objects and not any sorts of facts about how certain fictional stories were written, but rather facts about certain human social conventions. That’s a very different sort of “truthmaker.”
Or take the statement that 2 + 2 = 4. What makes that sort of statement true has to do, not with spatiotemporal relations between physical objects, or with how a certain work of fiction was written, or with human conventions, but rather with the necessary connections between certain concepts. (And what does that involve exactly? Good question, but however we answer it, it will not be like the other examples, and the “truthmaker principle” by itself will be pretty useless for helping us to answer it.)
There are other possible examples, such as statements about God, statements about angels, statements about possible but non-actual states of affairs, and statements about impossible objects (e.g. “There are no round squares”). Each will have a “truthmaker,” but not the same kind of truthmaker as in the other examples.
So, the “truthmaker principle” doesn’t really tell us much. In particular, it doesn’t tell us what sorts of things would have to make statements about the past true. It certainly doesn’t tell us that the truthmakers for statements about the past have to be like the truthmakers for statements about the present, any more than it tells us that the truthmakers for statements about Tony Stark, or about the conditions for an apology, or about arithmetic, or about the impossibility of round squares, have to be like the truthmakers for statements about cats and mats.
Hence, for all the truthmaker principle tells us, it may be that what makes it true that Julius Caesar was assassinated on the Ides of March is simply the fact that Caesar really was assassinated on the Ides of March. It doesn’t tell us that the truthmaker has to be a fact about something that exists, as opposed to being a fact about something that used to exist. The presentist can say that as long as it is the case that Caesar etc. are things that used to exist even though they don’t exist anymore, then we have a “truthmaker” for the statement.
Of course, the critic of presentism might object to this on various grounds. For example, he might insist that past events do in fact exist no less than present ones do, and that the existence of these past events is a more plausible candidate for being a truthmaker for the statement that Julius Caesar was assassinated on the Ides of March than the presentist’s proposed candidate is. But if that is how he develops the “truthmaker” objection, then he is simply begging the question against the presentist. For of course, the presentist would deny that past events exist.
Alternatively, the critic of presentism might avoid begging the question, and try to develop some other sort of response. He will no doubt say that there is something fishy about the idea of a fact that something used to exist. How can there now be a fact about something that is no longer real? If he is going to do that, though, then he might as well also say that there is something fishy about the idea of facts about fictional stories, or human conventions, or abstract entities, or possibilities, or round squares, or what have you.
But in that case, it is clear that it isn’t really the “truthmaker principle” per se that is doing the work in the so-called “truthmaker objection” to presentism. Rather, it is some other sort of ontological concern, such as a concern about the nature of facts. “Truthmaking” by itself is simply too vague a notion to do any serious metaphysical work.
So, as I say, I don’t think the “truthmaker objection” is very impressive or interesting. Bill disagrees. He asks us to consider the following propositions:
(1) There are contingent past-tensed truths.
(2) Past-tensed truths are true at present.
(3) Truth-Maker Principle: contingent truths need truth-makers.
(4) Presentism: Only (temporally) present items exist.
The problem, Bill says, is that “the limbs of this aporetic tetrad, although individually plausible, appear to be collectively inconsistent.”
But I would deny that there is any inconsistency. There is a presently existing fact that serves as the truthmaker for past-tensed truths such as the truth that Caesar was assassinated on the Ides of March – namely, the fact that Caesar really was assassinated on the Ides of March. To be sure, Caesar no longer exists and his assassination is no longer taking place. But the fact that he was assassinated on the Ides of March still exists.
To get an inconsistency, Bill would have to add to the list some further claim like:
(5) Only facts about what does exist (as opposed to facts about what used to exist) can serve as truthmakers.
But that would simply beg the question against the presentist. And of course the presentist would say: “There will be no inconsistency if you get rid of (5). ‘Problem’ solved!”
Bill also objects:
Feser seems to be proposing the following. In the case of the present-tensed 'BV exists,' the truth-maker is BV. But when BV is no more and it is true that BV existed, the truth-maker of the past-tensed truth will be the fact that BV existed and will not involve BV himself.
As it seems to me, this proposal betrays a failure to appreciate the difference between a fact construed as a true proposition, and a truth-maker, which cannot be a (Fregean or abstract) proposition. A truth-bearer cannot serve as a truth-maker. On one common use of 'fact,' a fact is just a true (abstract) proposition. We may refer to such facts as facts that. A fact that cannot serve as a truth-maker. Facts that need truth-makers.
End quote. In response, I would say that it is a mistake to identify facts with propositions. There is the fact that I am sitting in front of my computer, and there is the proposition that I am sitting in front of my computer. The first makes the second true, but it is not identical with the second. So there is no question here of the truth-bearer (namely the proposition) serving as a truth-maker (it is the fact, not the proposition, that is serving as a truth-maker).
Similarly, it is the fact that Caesar used to exist and was assassinated on the Ides of March that makes true the proposition that Caesar was assassinated on the Ides of March. The fact is not the truth-bearer; the proposition is. The fact is precisely the truth-maker.
Bill also criticizes a remark in my book to the effect that “the past and future don't have the same kind of reality that the present does” (p. 301). He objects that:
[O]n standard presentism, there is no distinction between kinds of reality. The claim is not that the wholly past and the wholly future have a different kind of reality or existence than the present, but that the past and future are not real or existent at all. On presentism, what no longer exists, does not exist at all. It passes out existence entirely; it does not retain a lesser kind of existence or exist in a looser sense of 'exist.'
End quote. This is true, and I will concede that my remark was phrased in a way that is potentially misleading if read out of context. But strictly speaking, what I wrote is correct. The past and future indeed don’t have the same kind of reality that the present does, precisely because they don’t have reality at all. (I think Bill is here making too much of an awkwardly worded phrase. As Bill himself acknowledges, I do make it clear elsewhere in my discussion that presentism denies that past and future objects and events exist at all.)
The point I was trying to make, in any event, is that past objects and events were real (unlike fictional objects and events, which never were). That fact is what serves as the truthmaker for statements about past objects and events. Statements about present objects and events have as their truthmakers a different sort of fact, viz. facts about objects and events that are real.
Bill also writes:
I conclude that Feser hasn't appreciated the depth of the grounding problem. 'Caesar was assassinated' needs an existing truth-maker. But on presentism, neither Caesar nor his being assassinated exists. It is not just that these two items don't exist now; on presentism, they don't exist at all. What then makes the past-tensed sentence true? This is the question that Feser hasn't satisfactorily answered.
End quote. In fact I have answered it. Yes, “Caesar was assassinated” needs an existing truthmaker. And that truthmaker is not Caesar or his assassination (neither of which exist anymore) but the fact that he was assassinated (which does still exist – after all, it is as much a fact now as it was yesterday, and will remain a fact tomorrow). To this Bill objects that “obviously this won't do [because] the past-tensed truth cannot serve as [its] own truth-maker.” But again, this conflates facts with propositions, and these should not be conflated.
The critic might respond: “But facts don’t ‘exist’ in the same way that tables, chairs, etc. do!” To which I would reply that that is perfectly true, but that there are also lots of other things that don’t exist in the same way that tables, chairs, etc. do – numbers, propositions, possibilities, God, and so on. So what? “Exists” is not a univocal term but an analogical one. If the critic thinks that every truthmaker must exist in exactly the same way, then, once again, his objection does not really rest on the “truthmaker principle” per se but on some other ontological concern.
One further point. Even if the defender of the “truthmaker objection” could get around the criticisms I have been raising, the objection nevertheless will succeed only if some alternative to presentism is correct. And as I argue in Aristotle’s Revenge, none of the alternatives is correct. So it will not suffice for the critic merely to try to raise problems for the presentist’s understanding of truth-making. He will also have to defend some non-presentist understanding of truth-making, which will require responding to the objections I’ve raised against the rivals to presentism.
In particular, the critic presupposes that we have a clear idea of what it would be for past objects and events and future objects and events to be no less real than the present is, and thus a clear idea of what it would be for such things to be truthmakers. But I claim that that is an illusion. The eternalist view is in fact not well-defined. It is a tissue of confusions that presupposes errors such as a tendency to characterize time in terms that intelligibly apply only to space, and to mistake mathematical abstractions for concrete realities. Indeed, on the Aristotelian view of time that I defend in the book, the approaches to the subject commonly taken by various contemporary writers are in several respects wrongheaded. Again, what I say about the truthmaker objection must be read in light of the larger discussion of time in Aristotle’s Revenge.