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Wednesday, March 20, 2013

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If I'm not mistaken, some presentists treat non-present times the way someone like Plantinga treats possible worlds: as maximal propositions. The present time is the lone true maximal proposition; our world is what is accurately described by the present time. Of course, such a view seems to require that propositions can change in truth-value, and that's not a view that some folks are willing to endorse. But I'm sure if one was more of a logician, one could find a way to avoid this result while preserving the spirit of this theory. If one could do so, then one could quantify over times in stating the presentist thesis without supposing that all times are equally real (or some other intuitive gloss on their thesis).

Thanks, John.

So they take an 'ersatzer' approach.

Let me see if I understand this. Each nonpresent time is identifed with a contingently false maximal proposition. The present time is identified with the one true maximal proposition. Now if these propositions are necessarily existent abstracta, then they are available to be quantified over. And if they are timeless as opposed to omnitemporal, then they are outside of time and the presentist thesis does not apply to them. So far, so good.

One problem I am having is this. I can see how maximal false propositions can be substituted for nonpresent times. But how the devil could the present time be identified with a maximal true proposition? This proposition describes the concrete universe as it exists right now, but it, being a proposition, is outside of time. How can the present moment be identified with an item outside of time, or even an item that exists at all times?

Further, the Nunc Movens, the moving now, which is part and parcel of the presentist scheme, must be located in the concrete universe. So it cannot be a proposition.

It can't be that all times are propositions.

I think the comparison to actualism is helpful. For someone like Plantinga, the actual world is a maximal proposition. It is the *true* maximal proposition. Our universe - the physical world in which we live - is not, properly speaking, the actual world. It is, if you like, the "actualized" world. It is what is accurately described by the actual world.

Likewise, the present time is a maximal proposition; it is the *true* maximal proposition. Our universe - the physical world in which we live - is not, properly speaking, the present time. It is, if you like, the "presentized" moment. It is what is accurately described by the present time.

To the extent that it is legitimate to say that the actual world is a maximal proposition, I think it is also legitimate to say that the present time is a maximal proposition. That does not require us to say that the world in which we live is a proposition. All we have to do is call the world in which we live something different (e.g., 'the "actualized" world' or 'the "presentized" moment'). And I don't see anything wrong with that.

I have no problem with saying that worlds are maximal propositions and that the actual world is the true maximal proposition, so long as we distinguish the actual world from the concrete universe.

But note that on this scheme actuality is truth. It follows that one cannot speak of the concrete universe as actual. For we cannot speak of it as true. So we cannot speak of the universe as actualized.

I also have no problem thinking of nonpresent times as false propositions. But if the present time is the maximal proposition that is true, then temporal presentness is truth. But the concrete universe cannot be true, hence it cannot be temporally present. But it must be temporally present to be the truth-maker of the maximal proposition that is the present moment.

There is a serious problem here, as it seems to me.

I'm not sure I see the disanalogy between times and people. If it is true to say 'Julius Caesar existed' then why can it not also be true to say 'Any moment t at which Julius Caesar existed existed'. In this case it is true that the moment t existed in the past, but not in the present. And that is exactly what the presentist thinks: claims of existence may be true about the past or future, but always with the tenses included.

If the existence status of persons and objects perish as they fade into the past, why not the existence status of the times as well? Reference is made to past individuals without claiming that they exist. Why can the same not be done with times?

Philip,

I didn't day that there is a disanalogy between times and people. Quite the contrary. The point is that if past individuals do not exist, then past times do not exist either. But then presentism cannot be formulated so as to avoid SPM.

We are at the intersection of metaphysics and logic.

>> But whatever we quantify over must exist: it must be there to be quantified over.

Am I alone in not seeing that this is obvious? Some examples that suggest otherwise:

1. We agree that Caesar does not exist now. Yet we presumably agree that 'Caesar was a Roman' and 'Caesar crossed the Rubicon' are also true now and from these it follows by existential generalisation that 'Some Roman crossed the Rubicon' is also true now. Is this not quantifying over the presently non-existent?

2. 'One of my siblings is older than me.' This is meaningful but false---I neither have nor had any siblings---and ought to count as quantifying over the non-existent. But said by someone with an older sibling it would be true.

3. 'Frodo is a hobbit; Frodo went to Mordor; therefore some hobbit went to Mordor.' This is valid but unsound. But in some possible world it is sound too.

Dr. Vallicella,

I don't know if this makes a difference but if I'm not mistaken, SPM is distinct from the view, which doesn't seem absurd to me, that

(PM) Only what exists in time at t = T exists in time at all, where T is the moving now, the time that happens to be the present moment. (The past and the future do not exist at all.)

PM seems like a commonsense, intuitive view: what happened a moment ago is "gone" and no longer exists. But according to SPM, as I understand it, I'm not justified in believing that there was "a moment ago" or that there will be a moment after now, and that's crazy. Can't one believe that the past does not exist without suspending or rejecting the belief that the past existed? This seems to be what Phillip was getting at too.

The critical question is whether PM, or a better formulation of it if I've made a simple mistake, entails SPM. If you like, Must that metaphysician be a lunatic who is of the present moment?

David,

Your reasoning in #1 is of course correct. Suppose I put it this way:

WAS(Caesar (is) a Roman)
WAS(Caesar (crosses) the Rubicon)
Ergo
WAS(Some Roman (crosses) the Rubicon)

WAS is a temporal operator: It was the case that _________. Its operands are tenseless sentences, sentences whose verbs and copulae are tenseless.

On this parsing we have quantification over what tenselessly exists. Thus I can account for the correctness of your reasoning without abandoning my theses that whatever we quantify over exists.

Bashar writes, >>PM seems like a commonsense, intuitive view: what happened a moment ago is "gone" and no longer exists.<<

You seem to be saying that presentism is commonsensical. I don't think so.

This is common sense: John Lennon died. He no longer exists: he did exist but does not now exist. His being shot is a past event. It is no longer occurring: it did occur, but it is not occurring now. But the presentist is not just retailing platitudes like these. He is saying something much stronger: John Lennon and his being shot do not exist at all.

Hi Bill,

Hope you are well. Long time no comment. Much has happened, but I'll spare you the details. (Suffice to say, I'm now pursuing a Spinozistic alternative to full-time philosophy work!)

I haven't checked your blog in a while, but decided to on a whim and couldn't resist the opportunity to chime about one of my favorite topics! Hope my 2 cents are helpful to you.

I think the difficulty you raise for presentism has an easy solution if we admit a distinction between three uses of the word "exists": (1) a present-tensed usage, where "exists" means "exists now"; (2) a tenseless usage (this might perhaps be equated with the disjunctive expression "existed, exists now, will exist, and/or exists timelessly"); and (3) a tense-neutral usage, which is used to express ontological commitment in a manner that is neutral between competing temporal ontologies. Sense (1) expresses what exists from the temporal vantage point of the present (e.g., "I am (now) commenting on your post"); sense (2) expresses what exists indifferently with respect to temporal vantage point (e.g., "2 + 2 is 4"); and sense (3) expresses what is simpliciter, that is, what "is" in the absolute or "unrestricted quantifier" sense (e.g., "God exists"). Considered tense-neutrally, "X exists" neither affirms nor denies that X has any special relation to the present (just as "God exists" neither affirms nor denies divine atemporality).

It is important to note that if "exists simpliciter" is not tense-neutral, then it will be very hard, if not impossible for us to do temporal metaphysics without begging the question from the outset against either the A-theory or the B-theory. A-theorists (not just presentists) will cry foul if we take "exists simpliciter" to be tenseless because for them existence is *fundamentally* tensed. B-theorists, likewise, will cry foul if we take "exists simpliciter" to be tensed because for them existence is *fundamentally* tenseless.

In the above terms, what presentism claims is that whatever exists simpliciter exists now, whereas the non-presentist claims that there exist simpliciter things that do not exist now. Neither statement is either paradoxical or tautological. This is a substantive metaphysical dispute.

To take your James Dean example, assuming that death is annihilation, the presentist should say that both "Dean exists now" and "Dean exists simpliciter" are (both now and simpliciter) false, and "Dean existed" is (both now and simpliciter) true. (The latter rules out SPM.) But the presentist should NOT affirm either "Dean exists" or "Dean does not exist" where those are construed tenselessly because, for the presentist, whether Dean exists is NOT indifferent with respect to what time it is.

Pace your reply to David above, temporal operators do not operate on tenseless sentences but on tense-neutral ones.

On further reflection, I wish to retract my suggestion that the tenseless sense of "exists" might perhaps be equivalent to the disjunction "existed, exists now, will exist, and/or exists timelessly".

I think a better way to express the tenseless sense of "exists" may be "(existed, exists now, AND will exist) OR (exists timelessly)". The first disjunct expresses omnitemporality. The second expresses timelessness. Either is a way in which something's existence would be indifferent with respect to which time is present.

Hello Bill,

One of the ways in which ~∃t:T.ϕ(t) can be true is if the type T is empty. The mere formulation does not require that there be objects of the type. This is where I think your easy argument goes wrong.

For a concrete example consider the standard proof that there is no rational square root of two. We start by saying Suppose there are such rationals; choose one in lowest terms, ie, numerator and denominator co-prime. But this, of course, turns out to be quantification over the empty set.

The logic of my Caesar example is flawed. The inference is only good if Caesar was a Roman and Caesar crossed the Rubicon at the same time.

Do you not think that the logic of untensed statements is rather weak? For Caesar (is) alive and Caesar (is) dead seem both true and there is no law of non-contradiction.

Hi Alan,

Great to hear from you. I've been thinking about you in connection with this topic, and it is very helpful to have your expert commentary. I am sorry to hear that you are now in pursuit of the modern-day equivalent of lens-grinding. If it is any consolation to you, I think you are more talented and productive than a lot of those who lucked out and found a way to make their living from philosophy. My best to you and your family.

It will take me some time to assimilate fully what you contributed, but I will make one quick comment now.

>>I think a better way to express the tenseless sense of "exists" may be "(existed, exists now, AND will exist) OR (exists timelessly)". The first disjunct expresses omnitemporality. The second expresses timelessness. Either is a way in which something's existence would be indifferent with respect to which time is present.<<

You say the first disjunct expresses omnitemporality. That's right. I take it we agree that an omnitemporal item is one that exists in time at every time. If God is everlasting (as opposed to eternal), then God is omnitemporal: he existed, he exists (present tense) AND he will exist. (I suppose we have to assume that nothing can have two or more beginnings of existence. Otherwise, 'existed, exists and will exist' could be satisfied by something that does not exist at every time.)

But I disagree that the first disjunct captures what we mean or ought to mean by 'tenseless existence.' Tenselessness, I take it, is arrived at by the abstractive operation of detensing: we abstract from the tense of a tensed verb or copula. Tensed: 'BV is blogging.' Detensed: 'BV was blogging or is (present-tense) blogging or will be blogging.'

Thus I am suggesting that the tenseless use of 'exist' is a disjunctively detensed use of 'exist.'

You say the second disjunct expresses timelessness. No doubt. But I would not say that eternal items (God and abstracta are candidates) exist tenselessly. They are not in time at all. Hence the sentences that express their existence and properies (e.g., 'God exists' and 'God is omniscient') are neither tensed nor detensed.

I incline to say that the eternal God is timelessly existent, not tenselessly existent.

I grant you that there is a tense-neutral use of 'is' and 'exists, but this involves a double abstraction. We focus on what is common to the detensed 'BV exists' and the timeless 'God exists.'

I count five uses of 'is/exists': the timeless, present-tensed, omnitemporal, disjunctively detensed, and tense-neutral.

How much of our disagreement is merely terminological and how much substantive is not at the moment clear to me.

Alan,

You say that temporal operators operate upon tense-neutral sentences, not tenseless ones. I don't get it.

You say that 'God exists' construed tense-neutrally leaves open whether God is a temnporal being or an atemporal being. Suppose the latter is the case. Then the following is nonsense:

It will be the case that God exists.

That makes sense only if God is in time.

So I say: temporal operators front detensed sentences.

Hi Bill,

Thanks for reply. It's fun to interact with you. You always push me to exceed my current cognitive limits, and I hope to some extent that I do the same for you. Iron sharpens iron.

Anyway, on to business. My initial thought when introducing my tensed/tenseless/tense-neutral distinction was that tensed sentences affirm a privileged present, tenseless sentences deny a privileged present, and tense-neutral sentences neither affirm nor deny a privileged present. This way of distinguishing things requires that tenselessness be understood as a positive denial of tense, rather than merely as a non-affirmation of it. If that's right, then a disjunctively tensed analysis of tenselessness is too weak. But I might be wrong about that. Perhaps it is better to think of tenselessness merely as the non-affirmation of tense. (In this case perhaps we should say that your timeless use of "is", rather than the tenseless use, is one that denies or excludes a tensed perspective.) But here the disjunctively tensed analysis of tenselessness is too strong, for it excludes other ways of not affirming tense, like your timeless sense of "is".

At any rate, whatever the correct analysis of tenselessness, the crucial distinction I believe is between existence-at-a-time and existence simpliciter. (Compare with the distinction between truth-at-a-time or truth-at-a-world and truth simpliciter.) Presentists like myself want to say that something exists simpliciter iff it exists now. (Likewise, I would also say that something is true simpliciter iff it is true now.) B-theorists and non-presentist A-theorists will of course dispute those claims.

Existence-at-a-time requires a tensed mode of discourse because to say that "X exists at time T" is to say that X would exist simpliciter were T present. (Likewise, to say that "X exists at world W" is to say that X would exist simpliciter were W actual.)

Saying that something exists simpliciter, however, requires a tense-neutral mode of discourse (lest we beg ontological questions from the get-go). I like to think of tense-neutrality as the perspective that would be had by an essentially omniscient being--one who is fully acquainted with all that is as it is. If presentism is correct, then the perspective of such a being includes only one time (the present), along with present memories and anticipations of other times. If the B-theory is correct, then the perspective of such a being includes a complete series of times, past, present, and future as seen from a timeless vantage point. (If the vantage point weren't timeless, then we would need a meta-time and ontological presentness would reemerge at that level. B-theorists can't allow that.)

I take "existence simpliciter" to be a primitive notion, one that is not semantically reducible to either "exists now", "existed, exists now, or will exist", "exists timelessly", or "exists omnitemporally". If presentism is correct, what exists simpliciter may be extensionally equivalent with what exists now, but the two aren't synonymous. Hence presentism is a substantive, non-tautological thesis.

PS. Supposing God is atemporal, it doesn't follow from "God exists simpliciter" that "It will be the case that God exists" is "nonsense", as you put it. All that follows is that it's false, which is just as it should be if God is atemporal. WILL(God exists atemporally) is nonsense, but WILL(God exists simpliciter) isn't. So I abide by my claim that (uncompounded) tense operators do not require tenseless operands. (For the record, I don't accept divine timelessness as I think that position is incompatible not only with the A-theory but, more importantly, with any sort of divine providence. But all that's for another time.)

Dr. Vallicalla,

I know this can't advance the discussion but I wanted to reply to your response, just for fun.

1. I didn't mean to imply that presentism is not a substantive thesis (I've been following the difficult discussion). But the moving now, and the passage of time, and the idea that there is no past to return to the way there's a "there" to go to, and yes, the proposition that John Lennnon's being shot does not exist at all anymore (does not exist simpliciter anymore, as Dr. Rhoda would say) seem closer to the common but vague sense most people have of what time is than the idea, say, that all things are like 'streaks' on a four-dimensional canvas or mosaic--and since that mosaic 'exists', all things, no matter what their 'time coordinates', 'exist' in exactly the same sense, 'simultaneously' if you will, somewhat like how all the images of an animated cartoon exist simultaneously while representing episodes that, within the story, are 'before' or 'after'.

I would deny that common sense is necessarily opposed to philosophical substance of thought. That a view is commonsensical shouldn't imply that it is trivial, uninteresting, or obviously true. Common sense can get things strangely right or fantastically wrong; a philosopher may work at a rigorous formulation of a commonsense inheritance, reinforced by or expressed in ordinary language and culture, and find, in principle, that it has wild implications. For me at least, presentism represents such an attempt to formulate or work out the implications of an ordinary, traditional, commonsensical but vaguely defined attitude towards time and existence. But of course, this common sense or intuition may be too vague, too broad, and even too conflicted, too confused perhaps, for adequate formulation in the manner of philosophy or in a single philosophical thesis. Maybe presentism represents just one element of the commonsense view of time and existence.

2. More than anything else, consider my "commonsense" a playful counterpoint to your "lunatic". If I seemed to be saying that PM is common to the inexpert many (how dare I anyway to say what common sense, with all its richness and complexity, amounts to!) you seemed to be saying that PM is endemic to the lunatic few. But I don't see that PM entails SPM.

Alan,

From the penultimate paragraph of 9:57, I gather that the following is your definition of presentism:

Necessarily, for any x, x exists simpliciter iff x exists now.

Thus you affirm the broadly logical equivalence of 'x exists' and 'x exists now' while denying that the two phrases have the same meaning.

Here is one question. Abstracta are arguably timelessly eternal, not omnitemporal. Consider the nuumber 13. It exists simpliciter. But it does not exist now or at any time: it is not in time. So 13 appears to be a counterexample to your definition of presentism.

You might reply that abstracta are not timeless but omnitemporal. Is that your view?

McCann argues that abstracta must be timeless. See here: http://maverickphilosopher.typepad.com/maverick_philosopher/2013/03/abstracta-omnitemporal-or-timeless-an-argument-from-mccann.html

Hi Bill,

This is a bit late to reply to your Wednesday 4:37 comment, but here goes.

I agree that in the modal case we have to sharply distinguish the actual world from the concrete universe. The actual world is the true maximal proposition, and it is true because it accurately describes the concrete universe in which we live.

So, likewise, I agree that in the temporal case we have to sharply distinguish the present time from the concrete universe. The present time is the true maximal proposition, and it is true because it accurately describes the concrete universe in which we live.

(Here I am leaving aside the interplay between modality and time.)

You say that in the temporal case, temporal presentness is truth. You also say that the concrete universe, which cannot be true, can therefore not be temporally present. With both of these I agree. What I am having difficulty seeing is the conclusion you draw from this: the concrete universe must be temporally present in order to be the truthmaker for the maximal proposition that is the present time. I do not see why this is true.

Compare the modal case. Actuality is truth. The concrete universe, which cannot be true, can therefore not be actual. But it doesn't follow that the concrete universe has to be actual in order to be the truthmaker for the maximal proposition that is the actual world. It just has to be, as it were, the entirety of reality.

Likewise, it seems to me, in the temporal case. The concrete universe does not need to be temporally present in order to be the truthmaker for the maximal proposition that is the present time. It just has to be, as it were, the entirety of reality.

Am I missing something crucial to your view here?

John,

The modal case and the temporal case stand and fall together. If there is the irreducible A-property, presentness, then I do not see how the concrete universe could fail to exemplify it. (This is so whether or not presentism is true, as long as there are A-properties.) Similarly, I don't see how the concrete universe could fail to actually exist (as opposed to possibly exist).

What I have trouble with is the idea that we can speak of the existence of the universe (or of any part of it) in a modally-neutral way. Similarly, I have trouble with the idea that we can speak of the concrete universe in a temporally neutral way, as we must if temporal presentness is identical to truth.

In other words, there is something viciously circular about trying to kick actuality and presentness upstairs to the second-level, the level of abstracta, which is what we do when we make of them properties of (Fregean as opposed to Russellian) propositions. If you recall that long paper on existence of mine that you commented on, my reasoning is similar to part of the reasoning in that paper.

On a Fregean approach to existence, existence is not a property of concete individuals, but a property of a property. Not a propery of Socrates, but a property of a property of Socrates. Which property? The property of being instantiated. And which other property? Socrateity, which is an abstract representative of Socrates.

The abstractist approach to actuality and temp presentness plays a similar game.

Intuitively, Obama exists, is actual, and is temp present. And these properties, as unusual as they are, belong to Obama: they are first-level. So itr seems to me that one moves in a vicious explanatory circle if one tries to account for existence is in terms of instantiation and actuality and presentness in terms of truth.

Hi Bill,

From what you've just said, I take it you're not persuaded by folks like Plantinga who say things like the following. An object o exists in a possible world w just in case, were w to be actual, o would exist. Thus, an object o exists in the actual world just in case, were the actual world to be actual, o would exist. Since, of course, the actual world is actual, o exists. My temptation is to say that all it is for Obama to be actual is to exist in the actual world, and that just means that were the actual world to be actual, Obama would exist. In a sense, Obama has an irreducibly modal property, namely, the property of being such that were a certain proposition to be true, he would exist. Likewise, Obama has an irreducibly tensed properly, namely, the property of being such that when certain propositions are true, he will exist. On this view kind of view, I am suggesting, Obama is actual and is present because he is such that, if a certain proposition were true, he would exist, and when certain propositions are true, he will exist. Maybe those aren't exactly what we would've thought the properties of being actual and being present would be for concrete individuals, but there does seem to be a sense in which the ersatzer can capture your intuitions.

More generally, if you're not friendly to this sort of mundane ersatzism, and you have never been tempted by Lewisian modal realism, I am curious about your own account of modality. In the temporal case, perhaps you're more inclined to eternalism.

John writes,

>>Since, of course, the actual world is actual, o exists.<<

You have to be careful here. It is not a matter of course that our world, call it Charley, is actual.

It is necessarily true that one of the worlds is actual. It is necessarily true that if w is actual, then w is actual. But it doesn't follow that if w is actual, then necessarily w is actual.
As it happens, Charley is actual. But Charley is not necessarily actual.

>> My temptation is to say that all it is for Obama to be actual is to exist in the actual world, and that just means that were the actual world to be actual, Obama would exist.<<

I would put it this way. Obama exists in some but not all worlds. One of the worlds in which he exists is Charley. To exist in a world is to be represented by that world as existing. Worlds are maximal Fregean propositions and Obama himself is in no proposition. Charley is actual (true). So Charley truly represents Obama as existing. For Obama to be actual is just for one of the worlds in which he exists to be true.

OK, but if a a contingent singular affirmative proposition is true then it needs a truth-maker. *Obama exists* needs actually existing Obama as its T-maker. So actuality cannot be removed from Obama and made a property of a proposition.

I will now begin writing a separate post on this to see if I can make it clear.

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