1 Introduction

The issue of how we should grasp the relations between presentism and the existence of the flow of time is a vague and unclear one. Some philosophers assume a single, standard ontological thesis saying about the existence of only the present while others claim that an acceptable formulation of presentism should entail the temporal passage in the form of temporal becoming,Footnote 1 and there still others who claim that the thesis about the existence of the flow of time is a fundamental claim of presentism.Footnote 2 There are even philosophers who claim that “Time does not pass given presentism.”Footnote 3 So it is an important metaphysical problem which cries out for clarification.

The majority of presentists introduce their view simply in the form:

P 1

Only the present existsFootnote 4;

or that

P 2

Only the present is real.Footnote 5

Such forms of presentism were criticized as leading to the triviality problem. The problem consists in saying when we examine the ontological theses of presentism that only the present objects exist, it turns out that both these ontological theses are trivially true or trivially false, depending on the way in which we understand the verb “exists”: in a tensed or tenseless way.Footnote 6 That is why many presentists—to avoid the triviality problem—transform their main ontological thesis into a more sophisticated form:

P 3

The domain of our most unrestricted quantifiers only includes the present objectsFootnote 7;

or

P 4

Only present things exist simpliciter Footnote 8;

or

P 5

Necessary, if x exist simpliciter, then x presently exists.Footnote 9

Presentists maintain—contrary to the claims of the adherents of the opposite views—that the past and the future do not exist, or that they are not real, or are not in the domain of our most unrestricted quantifiers, or that do not exist simpliciter.Footnote 10 They unanimously agree that the past was and that the future will be.

As it was recalled above, they sometime also assume, explicitly or implicitly, that the flow of time exists. Thus the important ontological issue arises: is the claim about the existence of the passage of time necessary for presentism? Perhaps it is unnecessary, or can it even be denied, as is claimed by Tallant (2010)? And maybe we should assume that it is a sufficient condition for presentism? It is the aim of this paper to examine these difficult questions: the problem of the necessity of the existence of the passage of time for presentism is examined in the second section, while the third section deals with the issue of whether the thesis about the existence of the flow of time in the form of becoming is sufficient for defining presentism. The paper ends with some conclusions.

2 Is the Existence of the Flow of Time Necessary for Presentism?

What I claim is that we should answer the question posed in the title positively. It was first noticed by St. Augustine that we should choose such an answer although, of course, he did not state the problem in such a form. In the well-known 11th book of the Confessions he wrote:

Boldly for all this dare I affirm myself to know thus much; that if nothing were passing, there would be no past time: and if nothing were coming, there should be no time to come: and if nothing were, there should now be no present time. Those two times therefore, past and to come, in what sort are they, seeing the past is now no longer, and that to come is not yet? As for the present, should it always be present and never pass into times past, verily it should not be time but eternity. If then time present, to be time, only comes into existence because it passeth into time past; how can we say that also to be, whose cause of being is, that it shall not be: that we cannot, forsooth, affirm that time is, but only because it is tending not to be? (St. Augustine 1912: 239).

St. Augustine claims here, as presentists do, that there is only present, and the past is no longer, and the future is not yet.Footnote 11 And he wrote in this passage also that if nothing passed away, the time called the past were not; and if nothing were coming, the time to come were not either; and if nothing were, then the time called the present could not be either. This means nothing other than that if the flow of time did not exist, the present would not exist either, and in such a case we could not claim that the past was and the future will be. And because the adherents of presentism maintain that the past was, that the future will be, the present exists, and that there was a time when our present events were in the future, they must admit the existence of the flow of time. The only possible alternative to avoid this conclusion is to understand the past as those events and things which are earlier than, the future as those events and things which are later than, and the present as those events and things which are simultaneously with a given moment of time. This maneuver, however, would lead to the static block universe of the eternalist in which everything exists tenselessly in their proper spacetime location and where there is no place for passing away and no place for the coming to be of events. Such a situation seems be inconsistent with what St. Augustine wrote about time and is also not acceptable for presentists. So, it follows from this that the presentists has to admit the existence of the flow of time; that is, they must accept the condition which I will call St. Augustine’s condition:

St. Augustine’s Condition

Presentism has to admit the existence of the flow of time.

And now the essential issue arises of whether any of the presentists’ theses P1–P5 alone really satisfies St. Augustine’s Condition. So the question is whether the existence of the flow of time can be inferred from the theses P1–P5 alone with no other assumption. Some philosophers claim that it is really possible. For example, Hestevold and Carter (2002) declare in their paper that “[a]n acceptable formulation of Presentism should make clear that Presentism implies Transient Time” (identified with the temporal becoming or the temporal passage),Footnote 12 while at the same time they claim that the main ontological thesis of presentism ought to be stated in the last form mentioned above:

Necessary, if x exist simpliciter, then x presently exists (2002: 493).

They claim that the presentism formulated in such a form implies a thesis termed by them Transient Time:

Transient Time: it is possible that objects and events undergo (in some sense) temporal becoming; in an irreducibly non-tenseless sense, it is possible that there did exist or did occur objects or events that do not presently (or will not), respectively, exist or occur; and it is possible that there will exist or will occur objects or events that, respectively, do not presently exist (or have not yet existed) or do not presently occur (or have not yet occurred).Footnote 13

Transient Time is contrasted by the authors with Static Time:

Static Time: Nothing can undergo temporal becoming; with respect to any (tenselessly) existing object or event, there cannot be an irreducibly non-tenseless sense in which it presently exists or occurs, did exist or occur, or will exist or occur.Footnote 14

Does Hestevold and Carter’s presentism really imply transient time? The authors claim that it does and introduce an argument which will be examined below. The mistake made in this reasoning is informative because it also shows why no other form of presentist thesis of the form P1–P4 can infer temporal becoming or the temporal passage alone. Hestevold and Carter’s argument has the following form:

  1. 1.

    Presentism is correct and transient time is incorrect. [assumption for reductio ad absurdum].

  2. 2.

    If presentism is correct, then Mozart exists only in the sense that there did exist something that was Mozart.

  3. 3.

    If transient time is incorrect, then there is a sense in which

  4. 4.

    Mozart exists other than the sense that there did exist something that was Mozart.

  5. 5.

    If transient time is correct, then static time is not correct.

  6. 6.

    Therefore, Mozart exists only in the sense that there did exist something that was Mozart. [from 1, 2]

  7. 7.

    Therefore, there is a sense in which Mozart exists other than the sense that there did exist something that was Mozart. [from 1, 3]

  8. 8.

    Therefore, Mozart exists only in the sense that there did exist something that was Mozart and there is a sense in which Mozart exists other than the sense that there did exist something that was Mozart. [from 5, 6]

  9. 9.

    Therefore, it is false that both presentism is correct and transient time is incorrect. [from 1, 7]

  10. 10.

    Therefore, either presentism is incorrect or Transient Time is correct. [from 8]

  11. 11.

    Therefore, if Presentism is correct, then transient time is correct. [from 9]

  12. 12.

    Therefore, if presentism is correct, then static time is not correct. [from 4, 10]Footnote 15

It is easy to show that this reasoning is invalid because the second step is not justified. To see this let us imagine a simple model of the possible world W † exactly similar to our present world W at some fixed moment t 0, but such that in W † there existed nothing in the past of t 0, and there will exist nothing in the future of t 0. It would be a static world with a momentary present at t 0 but without a flowing time, with no events and no things which existed in the past of t 0, and similarly without events and things which will exist in the future of t 0. It would be a “frozen” presentism, which, of course, is not in agreement with our experience, this is, however, not at issue. The point is that in the world W † Hestevold and Carter’s presentism is true and that it does not allow the inference from the presentist assumption of the (past) existence of any past event and any past object like, for example, Mozart. It means that the second step in the argument is not justified and the whole argument is invalid.

What is important, all other versions of presentism P1–P4 are true in the world W †, which means that it is impossible to infer from such ontological theses alone the existence of the flow of time. Of course, I do not support such a version of presentism: although such a view is logically consistent, it is not in accordance with our experience of the world and as such is of no interest for presentists. What I claim rather, after St. Augustine, is that presentists have to accept the existence of the flow of time and the theses P1–P4 alone do not suffice to define presentism.

There is one more argument in favor of the acceptance of the existence of the flow of time by the presentists. Namely, the presentists who do not assume the existence of the flow of time are vulnerable to attacks similar to that launched by Lewis (1986: 207), who claimed that every view denying existence of the future is implausible and irrational:

Consider the philosophers who say that the future is unreal. If ever anyone is right that there is no future, then that very moment is his last, and what’s more is the end of everything. Yet when these philosophers teach that there is no more time to come, they show no trace of terror or despair!Footnote 16

The presentists who assume the existence of the flow of time have no reason to despair: due to the existence of the flow of time, although the future does not exists at present, there is more time to come and—for better or for worse—there will exist in the future for sure.Footnote 17

If it is impossible to infer the passage of time from the theses of the form P1–P5, then perhaps presentists should define their position as a simple conjunction of one of these theses and a second concerning the existence of the passage of time? Certainly, it would be a better definition of presentism because St. Augustine’s condition would then be trivially satisfied. Nevertheless, such a solution has at least two flaws. Firstly, presentism defined with the aid of the two theses makes use of ontological notions of a different character: whatever notion we will apply to introduce the flow of time, it has to have a dynamic character, while the notion of the existence in the first thesis has a static character and such a solution would lead to an inhomogeneous view.Footnote 18 Secondly—and which I will try to show is more important —is that the thesis concerning the existence of the flow of time in the form of becoming, when properly understood, suffices to conceptualize presentism in a satisfactory way. This problem will be discussed in the next section.

3 Is the Existence of Becoming a Sufficient Condition for Presentism?

The usage of the notion of becoming to express the passage of time seems to be the most promising approach because it allows us to avoid the intractable question of the rate of time’s passage and Broad (1938) introduced his primitive notion of absolute becoming just to avoid the question about the rate of time’s passage. He noticed that the passage of time cannot be referred to itself because then the ratio of the same two quantities expressing the rate of time’s passage is meaningless. Neither can the passage of time be referred to a second time dimension, because in such a case the problem of the flow of time revives leading to regressus ad infinitum. He wrote in his famous quotations:

To “become present” is, in fact, just to “become”, in an absolute sense; i.e., to “come to pass” in the Biblical phraseology, or, most simply, to “happen”. Sentences like “This water became hot” or “This noise became louder” record facts of qualitative change. Sentences like “This event became present” record facts of absolute becoming. (Broad 1938: 280–281)

I do not suppose that so simple and fundamental a notion as that of absolute becoming can be analyzed, and I am quite certain that it cannot be analyzed in terms of a non-temporal copula and some kind of temporal predicate (Broad 1938: 281).

So, according to Broad, the flow of time consists in the (absolute) becoming of events. He ascribed absolute becoming to instantaneous events: he wrote that they come to pass, that is, that they come into existence to cease to be, where “existence” is understood in a tensed sense. If they “come to pass” or come into existence to cease to be, this means that they did not exist and will not exist although they come into existence at present. This is a clearly dynamic sense of becoming which is in agreement with our understanding of the passage of time. What is also important is that because it is said here that the events, which are now present, did not exist and will not exist, this conception of becoming fits perfectly well presentism, according to which there are no future and past objects. It is important since there are other ontological views which accept existence of the flow of time such as, for example, growing block universe, shrinking block universe, shrinking tree, or moving spotlight, which admit existence of the past or/and future objects and the notion of becoming assumed here excludes them.

The above interpretation of becoming as a dynamic process of coming into being to cease to be proposes the literal understanding of “coming to pass”, which seems to be in agreement with Broad’s intentions. A quite different interpretation was suggested by Savitt (2002), who proposed interpreting it in a minimalist way to receive the “Radical Middle” (2002: 161) between Broad and the well-known critic of the passage of time D. C Williams (1951):

Absolute becoming, as explained by Broad, is just the happening of events. Since events are located at various times or moments, they happen at various times or moments. Some events have happened, some are happening now, and others, we hope, will happen eventually. Some events occur simultaneously, some earlier than others, some later. Absolute becoming is the ordered occurrence of (simultaneity sets of) events. (Savitt 2002: 159–160)

Is this attempt at squaring the circle credible? Unfortunately, it seems implausible. Savitt—although he is known as a presentist—identifies the future with the events which happen later than others, the past with events which happen earlier than others, and the present with events which happen simultaneously with others in a typically eternalist way and thus this results in the static eternalist world where there is no place for coming to pass. He ignored the key expression “come to pass” in his interpretation which was used by Broad to introduce dynamics to his becoming, and interpreted “happen” in the static, tenseless way as “happen at time” —later, earlier, or simultaneously with other events—and as a result strips becoming of all of its dynamics. Such a notion of becoming is not in agreement with Broad’s intention and is useless for presentists.

Now, after assuming the dynamic interpretation of becoming, what remains is to introduce the notions of present, the past, and the future. So, to finish the construction of the proper definition of presentism, we only need to recall what presentists understand as the present. And there is a long tradition in presentism of identifying the present with what exists. To justify this claim, I recall some passages from Prior and his followers:

[T]o say that my lecture is present is just to say that I am lecturing—flat, no prefixes. The pastness of the event, that is its having taken place, is not the same thing as the event itself; nor is its futurity; but the presentness of an event is just the event. The presentness of an event is just the event. The presentness of my lecturing, for instance, is just my lecturing (Prior 1970: 247).

To be present is simply to be, to exist, and to be present at a given time is just to exist at that time—no less and no more (Christensen 1993: 168).

On a presentist ontology, to exist temporally is to be present. Since presentness is identical with temporal existence (or occurrence) and existence is not a property, neither is presentness a property. Presentness is the act of temporal being (Craig 1997: 37).

So, it follows from this that the presentist can identify the present with the totality of events that exists, and in a similar way the past with the totality of events that existed but ceased to be, and the future with the totality of events that will exist but do not yet exist. Now, if we recall Broad’s thesis about the passage of time as becoming of events, that is as their coming into existence to cease to be, we can easily see that Broad’s becoming leads precisely to the presentists’ ontological consequences, just those which form the presentist’s thesis P1–P5: events that we call present come into existence to cease to be. It means that no other ontological thesis is needed with the exception of the definition of the present, the past, and the future assumed above. In this way we gain an essential advantage over the standard formulation because the proposed one is only expressed with the aid of one thesis—which satisfies the St. Augustine Condition. It can be true or false, nonetheless it is certainly not trivial; Broad does not say that the present becomes or comes into existence. He says that events become or come into existence to cease to be. And Prior adds that we understand or define the present as that which exists. What is perhaps crucial is that neither Broad’s thesis nor Prior’s definition are trivial.

So presentism can be expressed, as I have tried to show, in the form of one thesis which I will call becoming:

Becoming

Events which our world consists of become or come into existence to cease to be.Footnote 19

This thesis is to be completed by the three definitions:

The present ≡

The totality of events which become or come into existence.

The past ≡

The totality of events which became or came into existence.

The future ≡

The totality of events which will become or will come into existence.

This analysis was performed in the language of events, but there is no difficulty to carry out it in the language of things (or things and events). To this end, it would be enough to recall Sellars’ notion of becoming which was ascribed to things: “only things can become in the sense of come into being,” (1962: 556) and to swap in the above analysis terms “events” for the terms “things” (or for the terms “things and events”).

I would like now emphasize some virtues of such a formulation of presentism:

  1. 1.

    It satisfies St. Augustine’s Condition, while no other form of presentism formulated as single thesis of the form P1–P5 does so.

  2. 2.

    It allows the expression of a dynamic character of reality, which presentism in the form of a single thesis of the form P1–P5 is not able to do.

  3. 3.

    It avoids the question of the rate of the passage of time because—as emphasized by Broad’s—the notion of becoming is primitive and unrelated to anything else, and especially not to time.

  4. 4.

    This formulation of presentism also avoids the triviality objection because the main thesis about the becoming of events (or things) is not trivial.

  5. 5.

    This formulation of presentism is consistent and—which should also be emphasized—homogenous: it is not composed of concepts of different types.

All these virtues seem to suggest that the proposed conceptualization of presentism should be assumed as the correct one and a better one than the standard formulation.

4 Conclusions

The paper has tried to show that presentism has to admit the existence of the flow of time to be in accordance with our intuitions concerning the present, the past, and the future. It also tried to demonstrate that the thesis concerning the existence of the flow of time in the form of becoming, when properly understood, suffices to conceptualize presentism in a satisfactory way. That is, it can be treated as the most fundamental thesis of presentism, from which we are able to infer the ontological thesis about the existence of only these events (and things) which we call the present. Such a formulation of presentism has some important advantages over the standard formulations, as I tried to show: it is homogenous, avoids the question about the rate of time passage, it is undeniable non-trivial, and emphasizes the dynamic character of the presentist’s image of the world. Because it gives us important benefits, it is worth considering it to be the successor to the traditional formulations.