Presentism under Threat

Presentism is usually understood as the thesis that only the present exists whereas the rival theory of eternalism is understood as the thesis that past, present, and future things are all equally real. Recently, philosophers of time (e.g. Crisp 2003, 2004a, b; Lombard 2010; Ludlow 2004; Meyer 2005, 2013a, b; Mozersky 2011; Savitt 2006; Tallant 2014) have paid a significant amount of attention to the so-called triviality objection, which allegedly shows that presentism is either trivially true or obviously false: Presentism is trivially true if it is read as saying that everything that exists now is present, and it is obviously false if read as saying that everything that has existed, exits or will exist is present. If this objection succeeds, its proponents argue, presentism cannot even get off the ground.

In this paper, I try to respond to the triviality objection on behalf of presentism. In second section, I will examine how the argument proceeds. In third section, I will reflect on three possible ways to respond but will argue that none of them succeeds in giving a satisfactory solution. I will then try to clarify the core idea of presentism and to suggest that if we characterise presentism accurately, the problem will disappear. In fourth section, I will offer such a plausible definition of presentism and will explain how it can avoid the triviality objection in more detail.

The Triviality Objection

Presentism is usually understood as the thesis that only the present exists or, equivalently, that everything is present. In semi-formal presentation, it amounts to saying that:

  • (P) For any x, if x exists, x is present.

  • (P) does not make clear, however, whether ‘exist’ in the formulation is present-tensed or not.Footnote 1 To say that something exists means either that it exists now or that it exists temporally (i.e. has existed, exists, or will exist).Footnote 2 According to the triviality objection, then, (P) is trivially true if it is understood to be saying that

  • (P1) For any x, if x exists now, x is present.

  • (P1) is trivial because to exist now and to be present are the same thing. On the other hand, (P) is obviously false if it is understood to be saying that

  • (P2) For any x, if x has existed, exists, or will exist, x is present.

  • (P2) is obviously false because there is an obvious counterexample. For instance, Socrates is not present but has existed previously.

Since the claim that (P1) is trivial is hard to deny, I will focus on the other claim that presentism is obviously false if read as (P2).Footnote 3 To examine it in more detail, I formulate the following version of the triviality objection:

  1. (1)

    For any x, if x has existed, exists, or will exist, x is present. [Presentism]

  2. (2)

    Socrates is not present. [Premise]

  3. (3)

    Socrates has existed. [Premise]

  4. (4)

    Therefore, presentism is false.

Premise (1) states the presentist thesis, which is the assumption for reductio ad absurdum. Premise (2) is a simpler way of saying that for some x, x was Socrates and x is not present. Premise (3) is a fact about the world that contradicts a consequence of Premises (1) and (2).Footnote 4

Before we move on to the next section, it may be worth noting that although the triviality objection aims primarily at defeating presentism, it can also be used to show that eternalism is either trivially false or obviously true if one takes it as the negation of (P). Meyer (2013b) is careful enough to notice this when he argues against presentism. Lombard (2010) is more ambitious and casts doubt on the significance of the debate between presentism and eternalism on the basis that neither of them is a substantial thesis. Savitt (2006) takes a somewhat moderate position and thinks that presentism and eternalism only differ in perspective. Thus, it is crucial for both presentism and eternalism to show that their disagreement is non-trivial.

Three Responses

In this section, I will consider some of possible responses to the triviality objection. In “Existentialist Presentism” section, I will examine whether presentists can avoid the problem by denying that there are singular truths about nonexistent things. In “Existence Presentism” section, we will see other attempts to defuse the objection. Since Tallant (2014) has conducted a relevant survey of the preceding discussions already, we will look at his solution. In “Nihilist Presentism” section, I will contemplate another possible response that has not been proposed before but which I believe is worth considering if we wish to get a firm grasp on the real problem. Following an examination of these three responses, however, I will argue that none succeeds.

Existentialist Presentism

One may complain that the triviality objection as it stands is unfair to presentism because it assumes something that presentists can or should resist. It starts from the assumption that there can be a singular proposition about a wholly past thing. If presentists are prepared to accept that singular propositions depend for their existence on the objects they are about, they may well hold that a singular sentence about a wholly past object does not express any (singular) proposition whatsoever. In particular, the singular sentence that Socrates is not present (but existed) does not express a proposition and therefore cannot be true or false. This being the case, it does not count as a counterexample to (P2).Footnote 5

I take it that this response has a close connection with what Crisp (2003) calls ‘existentialism’, although he rejects it. He says this:

Following Alvin Plantinga (1983), let us think of existentialism as the thesis that singular propositions depend for their existence on the individuals they are about …

To see why the presentist has trouble if existentialism is true, suppose that no present object is Lincoln. Given presentism, this is to say that nothing is Lincoln. Though it was the case that something is identical with Lincoln, this is true no longer. But given existentialism, if this is so, it follows that there are no singular propositions about Lincoln. And isn’t this absurd? (Crisp 2003: pp. 225–6)

Markosian (2004) suggests a similar line of thought but pursues it in the opposite direction. With reference to the sentence that Socrates was a philosopher, he says, ‘[The sentence] currently has no propositional content, because it is “trying” to express a singular proposition about the referent of “Socrates”, and there is no such thing’ (Markosian 2004: p. 68). Whereas Crisp thinks that the singular sentence about Lincoln is true and therefore existentialism is false, Markosian claims that something like existentialism is true and therefore no singular proposition is expressed by the sentence about Socrates.

If we accept existentialism, we cannot assume that every singular sentence expresses a proposition. Existentialist presentists may treat a singular sentence about Socrates in the same way that existentialist actualists treat a singular sentence about Sherlock Holmes, that is, by denying that it expresses a proposition. Surely, it is a logical truth (at least within the standard system of first order logic) that for any use of name a, there is something that is identical with a. In particular, it is true that Socrates is (or was) identical with himself. From this, one could proceed to argue that Socrates is not present and then conclude that for some x, x is (or was) identical with Socrates and x is not present. Were this acceptable, then Premise (2) of the argument presented earlier would be undeniable. It is doubtful, however, that any use of a name necessarily causes semantic or ontological commitment. If presentists are also existentialists, they can reject Premise (2).

As for (3), it is surely a fact about the world that Socrates has existed, but this claim is ambiguous, depending for its meaning on two possible readings, de re and de dicto. Crisp (2004a), for instance, would say that while it is true that it was the case that there is something that is Socrates, presentists may challenge the claim made of Socrates, that he has existed.Footnote 6 Once again, presentists, if they are existentialists, may simply respond that the latter singular sentence no longer expresses any proposition.

Although existentialism helps presentists to avoid the singularity problem of past truths that is caused by using a name, I suspect that it falls short of a full defence of presentism. To see this, we can replace (2) and (3) with some general sentences à la Russell (1905) and Quine (1948). First, we introduce the predicate ‘socratise’, such that

(Sc.) x socratises = df. x is a referent of ‘Socrates’ and for all y, if y is a referent of ‘Socrates’, y is identical with x.

Using this predicate, we can now reconstruct the triviality objection as follows:

  1. (1)

    For any x, if x has existed, exists, or will exist, x is present. [Presentism]

  2. (2*)

    For some x, x socratised and x is not present. [Premise]

  3. (3*)

    Anything that socratised has existed. [Premise]

  4. (4)

    Therefore, presentism is false.

Since (1) is the same as before, it will suffice to examine (2*) and (3*) to see whether this argument is sound.Footnote 7

To reject (2*), existentialism is of no help. Presentists may undoubtedly insist that while (2*) expresses a (general) proposition, it is plainly false because presentism is the thesis that there is nothing that is not present. To respond in this way, however, would be to beg the question. One cannot simply reject (2*) on the basis that everything is present because this is the initial presentist thesis that is under attack. If one claims that nothing that socratised exists now because it is not present, such a claim would be regarded as trivially true. On the other hand, if one claims that nothing that socratised has existed, exists or will exist because it is not present, such a claim would be regarded as obviously false.Footnote 8 To block (2*) is not as easy a task as it may seem.

Premise (3*) may need some disambiguation. Presentists may try to contend that (3*) is true if read as saying that it was the case that anything that socratises exists, but false if read as saying that for any x, if x socratised, x has existed. For the argument to stand, the latter disambiguation should hold. There is good reason to think that it does. If there is nothing that socratised, it is vacuously true that for any x, if x socratised, x has existed. If there is something that socratised, even a staunch defender of presentism could hardly deny that he has existed. In either case, we should accept (3*).Footnote 9 I therefore conclude that presentists cannot defuse the triviality objection by means of existentialism alone.

Existence Presentism

After conducting a comprehensive survey of the relevant issues, as discussed by Crisp (2004a, b, 2005a), Merricks (2007), Stoneham (2009), Sider (2006) and Zimmerman (1996), Tallant (2014) concludes that there have been no successful attempts to defuse the triviality objection. In a nutshell, he argues that the presentist theses advocated by these philosophers are unavoidably guilty of triviality when required to make clear what ‘exist’ means. Depending on whether it means temporal or present existence, presentism is in danger of being either trivially true or obviously false after all.

According to Tallant, it is not possible to escape from this difficult situation unless the close connection between being present and existing is recognised. He then tries to offer his own solution to the problem by giving a new definition of presentism. He suggests that the best way to accomplish this is to identify being present and existing, but he chooses to use the noun ‘presence’ rather than ‘being present’ as the name for this basic property or category. He gives the following two reasons:

However, talk of ‘being’ present, carries with it a slight awkwardness given the natural tendency to draw a close connection between existence and being; it looks to leave the same notion on both sides of the analysis.

In addition, I will have cause to talk of ‘presence’ being a name – of a property, category, etc. Talk of ‘being present’ is suggestive of an activity rather than a name. Thus, in what follows and in order to keep in mind that I am trying to talk about a thing, I will talk instead of ‘presence’ (rather than ‘being present’) and existence. (Tallant 2014: p. 494)

Tallant then defines what he calls ‘existence presentism’, as opposed to ‘conventional presentism’:

  • (EP) Presence is existence.

Making it clear that the copula ‘is’ in (EP) is tensed, Tallant claims that presence is the very same thing as existence. Since this claim is neither trivially true nor obviously false, says Tallant, (EP) is a substantial thesis. Whereas the triviality objection matters for conventional presentism, existence presentism is immune to such an objection.

One may still wonder how existence presentism can avoid the charge of triviality. At first glance, the move from talking of the verb ‘exist’ to the noun ‘existence’ does not make much progress. In the case of conventional presentism, use of the verb ‘exist’ always gives rise to a question with respect to its tense, and depending on the answer, presentists are accused of their claim being either trivially true or obviously false. In the case of existence presentism, which is defined in terms of the nouns ‘presence’ and ‘existence’, it appears that a similar question can be posed with respect to their adjectives. There are four possible readings of (EP):

  • (EP1) Present presence is present existence.

  • (EP2) Present presence is past, present or future existence.

  • (EP3) Past, present or future presence is present existence.

  • (EP4) Past, present or future presence is past, present or future existence.

As we can see, (EP1) is trivially true. (EP2) is obviously false because present presence and past existence do not necessarily coincide. Socrates (or something that socratises), for instance, does not have the property of present presence but has past existence. Likewise, (EP3) is obviously false because past presence does not entail present existence. Finally, (EP4) is trivially true because it amounts to saying that temporal presence is temporal existence. Surely, anything that is present at some time also exists at that time, and vice versa.

In my view, however, this objection misses the point. Tallant could respond that none of the objector’s interpretations gives us a proper understanding of (EP). While admitting that (EP1) is trivial, he might still insist that (EP) is not a disguised way of saying (EP1). In the case of conventional presentism, since the vast majority of verbs we consider (at least in English) need specification of tense, it seems legitimate to ask whether we are talking of temporal or present existence. By contrast, the same cannot be said of nouns. We can in principle use noun phrases without any adjectives prefixed. Generally speaking, if we succeed in referring to a thing by its name, the thing in question must exist as a self-sufficient entity prior to specifying what adjective to prefix to the name. Thus, once we allow ourselves to talk of ‘presence’ and ‘existence’ as different names of the same property or category, we need not specify which adjectives we prefix to them beforehand.

In addition, Tallant could deny that anything has the property of past or future existence. Some combinations of an adjective and a noun do not denote anything, even though they are grammatically acceptable. For instance, being a gold mountain and being a round square do not denote anything, even if each component of the two predicates is meaningful in itself. Similarly, Tallant might say that there is no such property as past or future existence. If so, we cannot interpret (EP) as (EP2), (EP3) or (EP4). In this respect, it seems to me, existence presentism has some advantage over conventional presentism. In fact, I believe that (EP) can be a substantial thesis if it is reformulated properly, as we will see in “Existence” section .

Nonetheless, I suspect that (EP) as it stands is far from a satisfactory definition of presentism. My first worry is that although it is legitimate to talk of presence and existence without any adjective prefixed, presentists also need to say more about the notion of temporal presence and existence. It is undeniable that some presently existent things have existed and will exist (unless they are instantaneous entities). In particular, I have existed for several decades and (hopefully) will exist tomorrow. Furthermore, we should not give up on such notions as presence-at-a-time and existence-at-a-time. After all, how can we deny that Socrates (or something that socratises) existed at some past time? If presentists can only talk of presence and existence but say nothing of presence-at-a-time and existence-at-a-time, this could be regarded as a serious defect. I am not asking here for a truthmaking story, only pointing out that presentists need to explain how they deal with temporal presence and existence as opposed to presence and existence in the literal sense. Presentists cannot avoid such a task simply by rejecting the truthmaker theory.

My second worry is that (EP), along with other ontological characterisations of presentism in general, may be insufficient to capture its core idea. Presumably, presentism and eternalism are two paradigmatically incompatible philosophical views of time. However, it is arguable that, in some possible worlds, even eternalists may accept (EP). To see this, consider the following logically possible worlds: (a) a world where nothing exists; (b) a world where only one thing exists in history; (c) a world where many things exist but they come into being and cease to exist simultaneously. If one of these worlds was to be actualised, we could hardly deny an ontological thesis such as (EP), whether we are presentists or eternalists, because everything that has the property of presence would also have the property of existence, and vice versa.

One can reasonably doubt that (a) is a real possibility (as I do). Moreover, it is far from clear whether any theory can be true or false in such a world (if it exists). We may well then replace it with less questionable possibilities, such as (b) and (c). In either case, the conclusion is the same: There would be no difference between the most inclusive domains for presentism and eternalism at any time. This is true on the assumption that a world can last as long as something exists; and this assumption also gives us a prima facie reason to reject the possibility (a). While (EP) may be neither trivially true nor obviously false in the actual world, I still hesitate to regard it as the definition of presentism.

Nihilist Presentism

The triviality objection assumes that there is something that was Socrates (or something that socratised). It may be said that presentists can reject this assumption if they also endorse nihilism or monism. Nihilists (e.g. Rosen and Dorr 2002) think that only things that really exist are mereological simples, fundamental particles that lack parts and compose no other things. Nihilists may not be committed to an outright denial of our ordinary belief, however. For instance, when we say that there is a table, they will say that there are fundamental particles arranged table-wise. Similarly, when we say that there is something that was Socrates, they will say that there are fundamental particles arranged Socrates-wise at some past time. Those fundamental particles may or may not be indestructible.Footnote 10 Suppose that they are indestructible. Given this additional presumption, nihilist presentists may say that there are fundamental particles that were once arranged Socrates-wise without this assertion committing them to the existence of Socrates.

On the other hand, monists (e.g. Schaffer 2007) think, very roughly, that there is only one simple, namely, a world that lacks parts. When we say that there is a table, they will say that some region of the world is table-shaped. Similarly, when we say that there is something that is Socrates, they will say that some region of the world is Socrates-shaped. Unlike nihilism, monism may allow presentists to have the same expressive power as eternalists without any additional presumption. When monist eternalists say that some region of the world is Socrates-shaped at some past time, monist presentists may say that some region of the world was Socrates-shaped a certain number of years ago. In monism and nihilism, it is never the case that Socrates has existed, exists, or will exist simply because there is no such thing as Socrates in reality.

The adoption of nihilism or monism may overcome the objection that presentism is obviously false, but the price is very high. Because only things that really have existed, exist, and will exist are simples, we are at a loss as to how to make sense of the ontological dispute between presentism and eternalism in the first place. Indeed, given nihilism or monism, any ontological characterisation of presentism, including (EP), would become trivial because there may be no wholly past or future things at the fundamental level. Here, we face the same problem as before but the present situation is more serious because we are in danger of trivialising the dispute not in other possible worlds but in the actual world: We have to take scenarios such as (b) and (c) in the previous section as actual possibilities. Does this mean that presentists and eternalists should reject nihilism and monism purely in order to maintain the significance of the debate? I would say not. Rather, I would suggest that other plausible definitions of presentism and eternalism should be sought that remain substantial regardless of the view taken on the fundamental nature of reality.

To summarise the discussion so far: I have argued (i) that existentialism cannot rescue presentism because the triviality objection can be raised in descriptive terms without using any name; (ii) that although existence presentism may have an advantage over conventional presentism, it is less than a complete success because of the potential problem of dealing with temporal presence and existence and the possibility of being trivial; and (iii) that we should look for a plausible definition of presentism that can be maintained as a substantial thesis independent of a metaphysics of fundamentality.

Redefining Presentism

In this section, I redefine presentism along the line that Tallant has suggested, aiming to defuse the triviality objection at the same time. Although my positive thesis is an extension of existence presentism in some ways, I have argued that we cannot regard (EP) as the complete definition of presentism. I will search for a version of presentism that provides a more comprehensive account of both temporal and non-temporal existence, and which remains substantial even for those hypothetical situations already considered. In due course, I will show that the version of presentism I offer can distinguish itself from other theories of time without falling prey to the triviality objection.

Existence

The moral I draw from the discussion of existence presentism is that it is necessary to examine the notions of non-temporal or non-time-relative presence and existence, and that they are prior to the notions of temporal or time-relative presence and existence. Tallant identifies presence and existence as the same property or category but it may be said that neither presence nor existence is a property. Tallant tries to alleviate any concerns this might cause in his paper. I think, however, that it is not necessary to shift from talking of the verb ‘to exist’ to the noun ‘existence’ in order to defuse the triviality objection. Instead, I suggest that the verb ‘to exist’ be retained and used consistently to ensure a firm grasp of non-temporal and non-time-relative presence and existence and their distinction from temporal and time-relative presence and existence. I will address these issues below.

To begin with, I argue that it is possible to make perfect sense of such concepts as existing simpliciter and being present simpliciter. To exist simpliciter is just to exist, without the addition of any adverb, and to be present is just to be present. These are not new concepts coined by presentists. Eternalists should also have (at least) the notion of existing simpliciter if they wish to resist temporal relativism about existence, according to which existence is always time-relative. Then, my first claim is this:

  • Claim 1: Existence and Presence

    • (ES) An object x exists now if and only if x exists simpliciter.

    • (PS) An object x is present now if and only if x is present simpliciter.

Although Claim 1 is presented in the form of biconditionals, I hold that the concept that appears on the right-hand side of each statement is basic. The claim is not that presentists are committed to the notion of tenseless existence but that the present tense is redundant. While Tallant talks of non-temporal or non-time-relative presence and existence, Claim 1 makes it possible to talk of existing simpliciter and being present simpliciter.Footnote 11

It is now easy to see that Tallant’s (EP) corresponds to the following thesis:

  • (EP*) To be present is to exist.

(EP*) says that anything that is present simpliciter exists simpliciter and vice versa. This claim is non-trivial under normal circumstances. Eternalists (or at least some of them) would say that existing at some time entails existing simpliciter precisely in the same way that existing at some place entails existing simpliciter.Footnote 12 Because Socrates exists at some past time, he exists simpliciter, according to eternalism. Nonetheless, Socrates is not present even though he was present. Therefore (EP*) is not true under eternalism. Of course, presentists have to resist such an inference by saying that existing at a time is not like existing at a place. In fact, neither having existed nor having been present (at some past time) entails existing or being present simpliciter if we are to accept Claim 1. While admitting that Socrates has existed and was present, presentists can reasonably maintain (EP*). Hence, it is not obviously false either.

Next, I try to define temporal or time-relative existence in terms of time-relative truth. Before doing this, I borrow an ersatzist way of talking of times from Crisp (2007). It does not matter which ersatzist theory we take, incidentally. The theory that Bourne (2006) offers, for instance, will work for the present purpose. Crisp joins earlier ersatzists in thinking of a time as a certain sort of maximal abstract object. He then defines a time as any proposition that satisfies something like the following:

  • 'x is a time = df. For some class C of propositions such that C is maximal and consistent, x is the proposition that, for any y, if y is a member of C, y is true,

where members of C are supposed to be propositions that contain neither P (past) nor F (future) tense operators. Whereas Crisp proceeds to claim that the proposition that ∀y (y∋C ⊃ y is true) is tenseless, I leave it open because I do not attempt to give a reductive account of tensed properties or tense in general. Having this definition of abstract times, Crisp continues to propose that abstract times form an ersatz B-series, a series of abstract times ordered by a primitive earlier than (or later than) relation. In what follows, we will make use of this idea of an ersatz B-series.

I define the notions of absolute truth and time-relative truth as follows:

  • Absolute Truth:

    • (AT) The proposition that P is true simpliciter if and only if P.

  • Time-Relative Truth:

    • (TT) The proposition that P is true at a time t if and only if t implies that P is true.

The present time t @ is the proposition that is one of the ersatz times and true simpliciter. Some times are past because they are earlier than t @ and other times are future because they are later than t @ . The following, then, is the definition of temporal truth:

  • Temporal Truth:

    • (PT) The proposition that P was true if and only if for some time t p , t p is earlier than t @ and t p implies that P is true.

    • (FT) The proposition that P will be true if and only if for some time t f , t f is later than t @ and t f implies that P is true.

As we can see, the notion of absolute truth is significantly different from the notions of time-relative and temporal truth. While time-relative and temporal truth are just matters of implication between propositions, absolute truth is not. Again, the notion of absolute truth is not just coined by presentists. Eternalists should also accept it if they wish to resist temporal relativism about truth, according to which truth is always time-relative.

We are now in a position to say that temporal or time-relative existence is not the same as existence in the literal sense. The same can be said of presence. Remember that to be present is to exist. I will therefore talk only of existence henceforth. We can observe that

  • Claim 2–1: Time-Relative Existence

    • (TE) An object x exists at a time t if and only if the proposition that x exists is true at t (if and only if t implies that the proposition that x exists is true).

Similarly, for temporal existence:

  • Claim 2–2: Temporal Existence

    • (PE) An object x existed if and only if the proposition that x exists was true (if and only if for some time t p , t p is earlier than t @ , and t p implies that the proposition that x exists is true).

    • (FE) An object x will exist if and only if the proposition that x exists will be true (if and only if for some time t f , t f is later than t @ , and t f implies that the proposition that x exists is true).

It should be clear that existing at a time does not entail existing simpliciter.

This line of thought accords with what Merricks suggested in Chapter 6 of his book Truth and Ontology, which Tallant also cites in his paper:

Now consider a view that starts with the eternalist’s picture of time and existence at a time, and then ‘shaves off’ the past and the future, leaving only a thin (instantaneous?) slice called ‘the present’. This view agrees with eternalism that existing at a time – at any time, past, present, or future – is like being located at a place. But, unlike eternalism, this view says that while objects exist at the present time, they exist at no other times, since there are no other times at which to be located. Such a view implies that everything is instantaneous.

This view is not presentism. Presentists deny that everything is instantaneous; they think that many objects not only exist, but also have existed and will exist. But I can see why some might think this view is presentism. They think this view is presentism because they (wrongly) ascribe to presentists the eternalist’s claim that to exist at a time is to be located at some super-thin slice of being. But presentists should no more accept this than the non-Lewisian should accept that to possibly exist is to be located in some universe. In fact, I think presentists should deny that there is anything at all – much less some super-thin slice of being – that is the present time, just as they should deny that there are past times or future times. (Merricks 2007: pp. 124–5)

Merricks is not the only person who says this. Prior, the originator of presentism, has also suggested a similar idea. He says that although philosophers often speak as if ‘the actual world is just a region of some larger universe which contains other regions as well – possible worlds, imaginary worlds, and so on’, this conception of actuality is ‘profoundly mistaken and misleading’ (Prior 1970: p. 245). He continues thus:

… It is tempting to think of the present as a region of the universe in which certain things happen, such as the war in Vietnam, and the past and the future as other regions in which other things happen, such as the battle of Hastings and men going to Mars. But to this picture there is the same objection as to the picture of the ‘real world’ as a box or region among other boxes or regions. It doesn’t bring out what is so special about the present; and to be more specific, it doesn’t bring out the way in which the present is real and the past and future are not. (Ibid.: p. 246)

It is now possible to understand what these presentists intend to say. I have explained why existing at a time does not entail existing simpliciter: The former is just a matter of implication between propositions whereas the latter is not. This is something that (EP) fails to address.

This is the end of story about existence. Before moving onto the next section, however, it would be wise to say more about the notion of existing simpliciter because different philosophers use the term differently. For instance, Meyer (2005, 2013b) thinks that to exist simpliciter means to exist temporally, outside time or in some other possible world. Lombard (2010), by contrast, suggests that to exist simpliciter should mean to be real. Whether or not any of these uses of the term is meaningful in itself, it should be clear that I consistently use it for non-temporal or non-time-relative existence in the above discussion. I have also pointed out that eternalists need this notion of existing simpliciter if they are to resist temporal relativism. By and large, the same can be said of the notion of being true simpliciter.

It may be tempting to think that to exist simpliciter means to exist tenselessly, but we should be careful here. For eternalists, if something exists at a time, it exists simpliciter. Given the fact that its existence at that time is tenseless, it is natural to think that the fact that it exists simpliciter is also tenseless. Thus, in eternalism, to exist simpliciter is to exist tenselessly. Presentists may also think that to exist at a particular time is a tenseless notion. This seems to be a natural thought if we accept the ersatzist framework, within which existing at a time is analysed as a matter of (logical) implication between propositions. For presentists, however, it is illegitimate to infer that something exists simpliciter from the mere fact that it exists at some time. In presentism, it does not follow that to exist simpliciter is to exist tenselessly.Footnote 13

In fact, it is a feature of my version of presentism that existing simpliciter is different from existing tenselessly. I have said that something exists now if and only if it exists simpliciter, but this should not be taken as a reductive (tenseless) account: Rather, it is a form of redundancy theory, according to which non-temporal or non-time-relative existence is essentially present-tensed. One may then object that it becomes trivial to say that to be present is to exist (presently). In reply, I say that what is crucial for my approach is the claim that to exist now is to exist simpliciter, which is of higher priority than (EP*). This claim is non-trivial in two ways. First, eternalists accept that if something exists now, it exists simpliciter but they deny the converse. Second, eternalists say that everything that exists at some time exists simpliciter but presentists should deny this, as Merricks and Prior would say. In particular, it is true to say that Socrates has existed or exists at some past time but this does not imply that he exists simpliciter.

I have said that in eternalism, to exist simpliciter is to exist tenselessly (i.e. to exist at some time) but that in presentism, it does not follow that to exist simpliciter is to exist tenselessly. One might then doubt that presentists and eternalists are talking of the same existence. It may be the case that they are not, but I still hold that they can at least disagree on what exists absolutely even if the notion of existing simpliciter can be interpreted differently in presentism and eternalism. Furthermore, how absolute existence (i.e. existence simpliciter) is to be understood is far from a trivial matter. In fact, I think that the ontological dispute between presentism and eternalism is over what it means to exist simpliciter; and the quantificational dispute (i.e. the dispute over the question of whether it is permissible to quantify over past and future things) is, in a sense, superficial for even presentists may say that Socrates exists at some past time although he does not exist simpliciter.Footnote 14

Property Possession

I have argued that there is a sharp distinction between existing simpliciter and existing at a time. It is easy to extend this idea and to draw the same distinction in the case of property possession. A thing has a property or is in a certain way but this is not always time-relative. For instance, I was straight 5 min ago but am now bent, and the latter does not seem to be a relative matter. Thus, there is a sharp distinction between having a property simpliciter and having a property at a time. Presentists should then endorse this:

  • Claim 3–1: Property Possession

    • (HS) An object x has a property F now if and only if x has F simpliciter.

As for time-relative property possession, presentists may say the following:

  • Claim 3–2: Time-Relative Property Possession

    • (TPP) An object x has a property F at a time t if and only if the proposition that x has F is true at t (if and only if t implies that the proposition that x has F is true).

Similarly, for temporal property possession:

  • Claim 3–3: Temporal Property Possession

    • (PPP) An object x had a property F if and only if the proposition that x has F was true (if and only if for some time t p , t p is earlier than t @ , and t p implies that the proposition that x has F is true).

    • (FPP) An object x will have a property F if and only if the proposition that x has F will be true (if and only if for some time t f , t f is later than t @ , and t f implies that the proposition that x has F is true).

While time-relative and temporal property possession are just matters of implication, presentists should hold to the prior notion of having a property simpliciter.

While eternalists may hold to the notion of existing simpliciter (and I think that they should), I wonder how they can make sense of the notion of having a property simpliciter. Arguably, eternalists cannot deal with such a notion adequately because of the well-known problem of temporary intrinsics (e.g. Johnston 1987; Lewis 1986; Merricks 1994): The problem is how a thing can be both F at one time and not F at another. To deal with this problem, they must either admit themselves to be temporal relativists about property possession or truth, or avoid relativism at the cost of accepting the perdurantist ontology of temporal parts that are supposed to have intrinsic properties simpliciter. (I will explain the eternalist predicament further in the next section.) However, this should not be a problem for presentists. After all, common sense tells us that some cases of property possession are not time-relative and that things undergo changes in their intrinsic properties. Hinchliff (1996), Zimmerman (1998), and several other philosophers have argued that to adopt presentism makes it possible to retain the common-sense view without any problem. Unless it is shown that there is a potential problem for presentists, they can retain the notion of having a property simpliciter and believe in real changes in things, as Prior (1968) does.

The Presentist Thesis

I offer here a version of presentism in its simple form. For this purpose, I introduce a technical term that defines the notion of a complete proposition:

  • p is a complete proposition = df. For some closed sentence S (whose variables and parameters are all filled in), S expresses p.Footnote 15

I suggest that the central contention of presentism is that sentences of the form ‘x exists (now)’ or ‘x has F (now)’ can express complete propositions that are true simpliciter. Since what is true simpliciter may change according to the passage of time, the simple definition of presentism can be put in the following way:

  • The Presentist Thesis

    • (Pr.) Some sentences of the form ‘x exists’ and/or ‘x has F’ express complete propositions that can undergo changes in absolute truth-values through time.Footnote 16

In (Pr.), I use ‘some’ rather than ‘all’ because it may be the case that not all sentences of the form ‘x exists’ or ‘x has F’ express complete propositions that can undergo changes in absolute truth-values. Presentists who believe in the eternity of mathematical objects may think that the sentence that a natural number exists expresses a complete proposition whose absolute truth-value cannot change. In addition, even a sentence about a material object may not necessarily express a complete proposition that can undergo changes in absolute truth-values through time. For instance, the sentence that George W. Bush is a son of George H. W. Bush expresses a complete proposition whose absolute truth-value cannot change. Having this in mind, I will show in what follows that (Pr.) provides a robust and comprehensive definition of presentism without being guilty of triviality.

Consider the existential case first. Presentists and eternalists can agree on the following:

  • The sentence that Barack Obama exists (now) expresses a complete proposition that is true simpliciter.

The proposition that Obama exists is true simpliciter if and only if Obama exists. For presentists, since to exist now is just to exist, and Obama exists now, the sentence expresses a complete proposition that is true simpliciter. For eternalists, the inference is slightly different. If eternalists deny temporal relativism about existence, they would think that ‘to exist now’ entails ‘to exist at some time’, which in turn entails ‘to exist simpliciter’. Since Obama exists at the present time, he exists. If eternalists also deny temporal relativism about truth, they reach the same conclusion, namely, that the sentence expresses a complete proposition that is true simpliciter. Therefore, in the case of presently existing objects, such as Obama, there is no significant disagreement between presentists and eternalists, as one would expect.

Temporal relativists about truth, on the other hand, would deny (Pr.) because there are no complete propositions that can be true simpliciter. Temporal relativists about existence would also deny (Pr.) because sentences of the form ‘x exists’ express no complete propositions without specifying times and dates. To deny (Pr.) either way, however, would make it neither trivially true nor obviously false because the commitment to relativism is highly controversial.

The situation is different in the case of wholly past (or future) objects. Eternalists would assert the following:

  • The sentence that Socrates exists expresses a complete proposition that is true simpliciter.

Since Socrates exists at some past time, eternalists would think that he exists simpliciter unless they are temporal relativists about existence. Thus, eternalists would conclude that the sentence expresses a complete proposition that is true simpliciter unless they are temporal relativists about truth. Presentists, on the other hand, should resist such an eternalist inference. They should think that while Socrates has existed, this does not entail that he exists simpliciter. Although the sentence that Socrates exists might express some complete proposition (because it has the same form as the sentence about Obama), the proposition is no longer true simpliciter but was true or is true at some past time. Thus, the proposition has undergone a change in absolute truth-values. (Alternatively, if one is an existentialist presentist, it may be thought that the singular proposition itself has undergone an ontological change while the general proposition that something that socratises exists has undergone a change in its absolute truth-values.) In the case of non-present objects, such as Socrates, presentists and eternalists should disagree.

Presentists and eternalists disagree not only about what is true simpliciter but also about whether some complete propositions can undergo changes in absolute truth-values. Presentists may say that the sentence that Socrates exists expresses a complete proposition that was true once before but is no longer true simpliciter, whereas eternalists will say that it expresses the same complete proposition that holds true once it is true simpliciter. It would be instructive to compare the temporal case with the modal case. Actualists and modal realists disagree on what is true simpliciter, but they may agree that a proposition about existence cannot undergo changes in absolute truth-values. If actualists are eternalists, they will say that the sentence that Socrates exists is true simpliciter, though it could be false in some world. If modal realists are eternalists who deny modal relativism about existence and truth, they will also say that the sentence expresses a proposition that is true simpliciter because Socrates exists in the actual world. In either view, the proposition holds true unchangingly once it is actually true. Thus, the disagreement between presentists and eternalists is much deeper than one may expect, and (Pr.) characterises what is at stake in the debate adequately.

Let us turn to the ideological case. Suppose that President Obama is now making a speech to an audience. Presentists would say the following:

  • The sentence that Obama is speaking expresses a complete proposition that is true simpliciter.

Since Obama is not always making a speech, the sentence expresses a complete proposition that will undergo changes in absolute truth-value. In the present case, however, eternalists cannot even say that the sentence expresses a complete proposition that is true simpliciter because of the problem of temporary intrinsics – unless they buy the perdurantist ontology of temporal parts. Even if eternalists endorse perdurantism, they still deny (Pr.) because the present temporal part of Obama is permanently speaking and therefore the sentence does not express a complete proposition that can undergo any changes in absolute truth-values. Such changes are simply impossible if perdurantism is true. Worm theorists who believe that ‘Obama’ picks up the mereological sum of his temporal parts may have a different response, but this would not affect the point I am making. According to the worm theory, Obama is speaking if and only if the mereological sum of his temporal parts includes one that is speaking. If Obama has such a temporal part, he will never lose it, and therefore the sentence that Obama is speaking should express a complete proposition that holds true forever. Thus, perdurantist eternalists deny (Pr.).

If eternalists deny perdurantism, they should accept either temporal relativism about property possession or truth. If they accept temporal relativism about property possession, they must say that Obama cannot have any property simpliciter: He can have a property only relative to a particular time. If so, the sentence that Obama is speaking does not express any complete proposition at all. If they accept temporal relativism about truth, they can maintain that the sentence expresses a complete proposition but they must admit that such a proposition cannot be true simpliciter: It can be true only relative to a particular time. Either view strikes me as unpalatable in itself if the common-sense position is to be taken seriously. More importantly, in each view, no sentences of the form ‘x has F’ express complete propositions that can undergo changes in absolute truth-values. It may therefore be concluded that (Pr.) is neither trivially true nor obviously false. It is not trivially true because eternalists deny it in some way or other. It is not obviously false because the commitment to perdurantism or temporal relativism about property possession or truth should be highly controversial.

One might think that (Pr.) would fail to distinguish presentism from other A-theories: the growing-block theory (e.g. Broad 1923; Tooley 1997) and the hybrid A-B theory (e.g. Schlesinger 1980; Smith 1993). According to the growing-block theory, reality consists of things that are actual as of the present moment, and that the sum total of existence is increasing toward the future. In this theory, some sentences of the form ‘x exists’ express complete propositions that can undergo changes in absolute truth-values through time. We should note, however, that the growing-block theory is half-eternalist about the past. Therefore, what I have said about eternalism applies to the growing-block theory at least with regard to past cases. In particular, growing-block theorists must say that a sentence of the form ‘x exists’ expresses the same complete proposition that holds true once it is true simpliciter. Moreover, they will encounter the identical problem concerning property possession that faces eternalists, so they must deny (Pr.) after all.

According to the hybrid A-B theory, in addition to the eternalist ontology, there are irreducible properties of pastness, presentness, and futurity attributed to things and events in time. If such properties exist, some sentences of the form ‘x has F’ may express complete propositions that can undergo changes in absolute truth-values because what is future will become present and then past. Nonetheless, (Pr.) can distinguish presentism from the hybrid theory because it says that some sentences of the form ‘x exists’ also express complete propositions that can undergo changes in absolute truth-values. Hybrid theorists, by contrast, rule out the possibility of ontological changes and agree with eternalists that the sum total of objects that exist remains constant. Thus, the hybrid theory clearly contradicts the ontological aspect of (Pr.).

Finally, (Pr.) stands as a substantial thesis regardless of what possible world we consider or which view we take on the fundamental nature of reality. Let us confirm the latter point first. (Pr.) is not rendered ineffective by any metaphysics of fundamentality because simples – (indestructible) particles or the world – can in principle undergo changes in properties and relations even if they do not undergo any ontological changes. In fact, what happens in the world is incessantly changing in various ways, and this shows that simples do change at least in their properties or relations. Therefore, (Pr.) is a substantial presentist thesis and is not threatened by nihilism or monism.

Nor is it made ineffective by any exotic scenario. Suppose that there is a world where nothing changes ontologically or ideologically. Even eternalists would then accept an ontological thesis such as (EP). By contrast, (Pr.) can still distinguish presentism from eternalism because it is formulated in modal terms: Some complete propositions can undergo changes in absolute truth-values. This claim is true if there is a world in which some complete propositions undergo changes in absolute truth-values through time. Presentists can argue that the actual world happens to be such a world, whereas eternalists must say that no complete propositions can undergo changes in absolute truth-values in any world. This is why the two theories of time are incompatible. A comprehensive and robust definition of presentism is thus formulated that can avoid the charge of triviality and remain substantial regardless of what possible world exists and how things are in reality.

Conclusion

To sum up, I have shown how to avoid the triviality objection by giving a new definition of presentism. To clarify the core idea of presentism, I have suggested that there should be a sharp distinction between existing simpliciter and existing at a particular time. Extending this idea, I have drawn the same distinction in the case of property possession. I have also explicated the notion of temporal or time-relative existence and property possession (as opposed to non-temporal or non-time-relative existence and property possession) in terms of an ersatz B-series. Finally, I have offered a version of presentism as the thesis that sentences of the form ‘x exists’ and/or ‘x has F’ express complete propositions that can undergo changes in absolute truth-values through time. This thesis is neither trivially true nor obviously false. In addition, it can characterise presentism uniquely and remain substantial regardless of whichever world pertains or whichever view is adopted concerning the fundamental nature of reality.