Against Eternal Truth in the Metaphysics of Time

Cadenkumar Hise • California State University, Fullerton

Introduction

An ongoing debate within contemporary metaphysics of time involves discerning which theory of time is real. The two most popular contenders within this debate are the A-theory of time and the B-theory of time. The A-theory consists of a series of positions of time as running from past to present to future or the opposite. Time can be understood here as a linear trail that traces the continuity of time. The B-theory consists of a series of positions of time as either earlier or later than another position of time. Time in the B-theory does not ‘move’ in the same way as in the A-theory, but is rather understood to be relational. Both theories of time have robust defenses and take on many different forms.

Adapting Michael Devitt’s definition of metaphysical realism, a given theory of time must hold that the two following premises are true in order to be classified as real:

Time can be said to exist.
Time exists objectively, and independently of our cognitive activities.

A given theory of time is true iff both of the premises above are true. I will argue that the B-theory of time is real, but cannot and ought not reach toward eternal truth. In Section 2, I will explicate the A-theory and show that it does not meet premise (1) or premise (2). In Section 3, I will show how the B-theory solves the problems of the A-theory and meets premise (1) and premise (2). In Section 4, I will argue that the B-theory problematically reaches toward eternal truth. I will show that it cannot reach eternal truth, and is therefore not real by its own standards. I will conclude from here that, in order for any theory of time to be real, it must not reach toward eternal truth.

§2: Indexicals and Truth-Values

The version of the A-theory that I will be focusing on in this paper is presentism. Recall that the A series of time consists of events running from far past, to near past, to present, to near and far future. The presentist will argue that only the present is real, that it is unique and privileged in the sense that it is the only real, actual world. A. N. Prior argues for this by saying that “the reality of the present consists in what the reality of anything else consists in, namely the absence of a qualifying prefix.” A qualifying prefix justifies, or qualifies, the reality of a statement. Prior gives us the example of a hypothetical professor named Scott lecturing. To say that Scott will lecture in the future, we must say, “It will be the case that Scott is lecturing.” To say that Scott has already lectured, we must say, “It was the case that Scott is lecturing.” To say that Scott’s lecturing is taking place in the present, we say, “Scott is lecturing.” To Prior, the lack of a qualifying prefix in “Scott is lecturing” constitutes the reality of the present over the past or future. Fictional, mythological, or imaginary objects and objects from the past or future need qualifying prefixes for us to discuss them in the present. Therefore, according to Prior, they are not real. A past fact may qualify as real and a fact at the present qualifies as real. Put differently, insofar as something remains true or is true, it is real and exists in the present. This conception of reality is constantly shifting and changing, as present facts shift and change as time progresses.

Dean Zimmerman also defends presentism through the use of a “serious tenser” approach. Because propositions are tensed entities, they are not always true or false, but are, were, or will be true or false. Their truth or falsity is a tensed matter. For example, take:

The apple is (presently) green.
The apple was green.

Imagine the apple starts out green at t1. At t2 the apple begins to turn red, and at t3 the apple is red. At t1, (a) is true and (b) is false. But, at t3 (a) becomes false and (b) becomes true. On this view, one’s having a property (in this case, greenness) is, metaphysically speaking, always something that occurs in the present. Put differently, one can make claims about the past, present, and future insofar as they are speaking from the point of view of the present. The reason why (b) is true at t3 is because of the past tense ‘was,’ which positions the speaker in the present making claims about the past in relation to the present.

J. J. C. Smart critiques the A-theory on similar semantic grounds. He argues that the A-theory relies too heavily on tenses and indexicals to make true claims about the reality of time. According to Smart, tenses and indexicals relativize the truth of a sentence to a person and time. Recall the sentence (b) above. The truth of this sentence is relative to an entity x making a claim about the apple’s greenness in the past from the point of view of the present. As such, the truth value of (b) is relative to x. What of (a), then? That sentence incorporates the verb is, which seems to be tenseless. This is not the case, as in presentism, verbs are always tensed. “Even the tenseless ‘is’ of mathematics gets thought of as ‘always was, is, and always will be’, thus sullying the purity of mathematics with temporal reference.” As such, we run into the same problem as (b), where tense relativizes the truth of (a) to the person making the claim from the point of view of the present about the present. Furthermore, recall the utterance, “Scott is lecturing.” The truth of this sentence is relative to the indexical ‘Scott.’ The presentist, then, is not referring to intrinsic properties of events or objects in describing them as present but is incorporating tense and indexicals to make claims with a relative truth value.

This charge is sufficient for us to conclude that claims within presentism are true only relative to the person making them. Put differently, claims in presentism do not hold truth value outside of our cognitive activities. But, this is not sufficient for us to claim that time itself in presentism does not exist independently of our cognitive activities. To prove this, I will turn to McTaggart’s famous argument against the reality of time. If A-theory properties of events are relational, then past, present, and future must be incompatible properties. No event can be more than one at the same time. A defender of the A-theory might try to solve this incompatibility by claiming that, since time is successive, no event will be past, present, and future at the same time. But, in saying that time is successive, the defender assumes the existence of time. It is not given to us that time is real, since that is exactly what we are trying to prove. As such, McTaggart shows that we find ourselves in a vicious circle of begging the question. In other words, we rely on the A-theory to argue for the existence of the A-theory. We can conclude from here that the A-theory cannot exist nor make true claims about reality outside of our cognitive activities.

If we accept the arguments above, presentism cannot exist independently of our cognitive activities. Presentism relies on outside entities, tenses, and indexicals to make true claims about reality. As such, all truth is relative to a particular individual making claims about time. Time cannot exist objectively outside of that subjective experience. We can conclude from here that the A-theory does not exist independently of our cognitive activities and therefore does not satisfy premise (1) or premise (2). Time is therefore not real within the A-theory.

§3: Towards a Tenseless Model of Time

In this section, I will briefly explicate Smart’s defense of the B-theory to show that it meets premise (1) and premise (2). This will show that Smart’s B-theory exists and exists independently of our cognitive activities.

Recall that the B-theorist criticizes the A-theorist for using indexicals and tensed language, relativizing the truth of claims made within the A-theory. Smart believes we can tweak the semantics of A-theory language to tenseless B-theory language and avoid relativizing the “truth of a sentence to a person and a time.” Borrowing from Donald Davidson’s ‘date theory,’ Smart shows that “sentences such as ‘I am tired’ is true as (potentially) spoken by person P at time t if and only if P is tired at t and ‘I was tired’ is true as (potentially) spoken by person P at time t if and only if P is tired at a time earlier than t.” Using Davidson’s date theory, Smart semantically shifts tensed language in the A-theory to tenseless B-theory language. Without relying on tense and indexicality, the truth of claims within the B-theory, insofar as they are expressed in the metalanguage, avoid cosmic parochiality. Put differently, the truth of a given claim in the B-theory is not relative to our cognitive activities, but eternal. We can conclude from here that premise (2) is met, but what of premise (1)?

McTaggart argues that change is not possible within the B-series. Since change is not possible, and time necessarily involves change, the B-series is not real and cannot exist. Change is not possible in McTaggart’s B-series because, for him, change can only happen to events. Since Event M will always be earlier than Event N, and N always later than M, there is no change. Smart argues against this by saying that “things and processes can change, events happen.” The B-theorist can therefore elucidate change as “immediately adjacent temporal stages of a thing or process having different properties.” By changing the subject of change from events to things or processes, Smart allows for change to exist in the B-series. Avoiding McTaggart’s charge, the B-series can be said to exist, thus meeting premise (1).

§4: Rejecting Eternal Truth

In this section, I will attempt to show that, despite meeting premise (1) and premise (2), Smart’s B-theory is not real by its own standards. I will do so by introducing a problematic third premise that Smart’s B-theorist misguidedly argues for. I will conclude from here that Smart’s B-theory cannot, and ought not aim toward eternal truth.

The B-series meets premise (1) and premise (2). Therefore, the B-series is real by Devitt’s definition of realism. Since the A-theory does not meet premise (1) or premise (2), it is not real. Beyond these two premises, Smart argues that another reason to prefer the B-theory over the A-theory is because truths within the B-theory “are, in a sense, eternal truths, not sempiternal ones as the A-theorist will contend.” Sempiternal here can be understood as eternal and unchanging, but within the bounds of time–earthbound. So, according to Smart, we ought to prefer the B-theory over the A-theory because it offers us truths not relative to anything or anyone. We can derive a third premise from here in addition to the first two:

Time can be said to exist.
Time exists objectively, and independent of our cognitive activities.
Claims about time are eternally true; not relative to anyone or anything.

Does Smart’s B-theory meet premise (3)? I will argue that it does not. No theory of time allows us to see the world “sub specie aeternitatis, or from the point of view of the universe.” Before I explain why I do not think so, I will explicate why Smart believes the B-theory accomplishes this, and why he thinks it should.

Metaphysics, to Smart, “should not be cosmically parochial.” If we do metaphysics cosmically parochially, we may fall into egocentrism and anthropocentrism. Choosing to only adopt a limited perspective while ignoring what is actually true prevents us from doing metaphysics in the most accurate way. When we use tensed language, we are tempted into this egocentric and anthropocentric view of the world. Adopting the tenseless language of the B-theory allows us to escape this parochiality and take the universe’s point of view. Smart also appeals to the physical sciences. He argues that truths within chemistry and physics are eternal truths since they incorporate tenseless language. To Smart, since the truths within the physical sciences are eternal, the truths within metaphysics ought to be as well.

Smart’s account thus crucially hinges upon language and physical science being able to afford us with eternal truth. Neither language nor physical science are able to provide eternal truth. P. F Strawson argues that “neither Aristotelian nor Russellian rules give the exact logic of any expression of ordinary language; for ordinary language has no exact logic.” So, when we rely on Davidson’s date theory to create a metalanguage that turns our claims into first-order logic, we implicitly imply two things. First, that the logic represented by the date theory accurately represents the meaning of a given sentence, and second that said logic provides us with eternal truth. But, as per Strawson, there is no exact logic to be found within language. Language is constantly shifting and evolving, and meaning is relative to particular conditions and ways of being. To assume that the date theory exacts meaning to a level of eternality is to assume that the meaning we ascribe to a particular sentence represents its eternal meaning. This, in itself, is incredibly egocentric and anthropocentric.

To accept that argument against eternal truth, we must accept that it is impossible for us to go beyond our particular conceptual or linguistic schemes. Put differently, we must accept linguistic relativity. Linguistic relativity amounts to the idea that “in order to say anything you must adopt a language. What you say, i.e., the utterances you make, the sentences you affirm, are not true or false absolutely, but are true or false only relative to a given language.” If we accept this, it follows that tenseless language does not express eternal truth. Therefore, Smart’s B-theory cannot express eternal truth.

There is also a level of scientific realism that displays itself in Smart’s conception of the B-theory. His appeal to the ‘eternal truths’ expressed through the physical sciences implicitly argues for scientific realism. This conception of science argues that, through continuous scientific discovery, convergence on some final ontology or ideology will become clear to us. Put differently, the more about science we learn, the more about reality we learn. Eventually, we will know so much about science that we will be able to understand reality at its core. Putnam convincingly argues against this by saying that “scientific realism is not acceptable, if only because of the history of science induction, which precludes any reasonable expectation of convergence on one final ontology and ideology.” Putnam shows us that the paradigms and goals surrounding science change with time. To assume that science is continually reaching toward some eternal truth is wrong, precisely because science is pragmatic. The truths it aims towards are relative to a particular time and place.

If we take scientific realism to be dubious, as Putnam does, it follows that relying on physical science to provide us with eternal truths about reality is untenable. Even if we could rely on language to provide us with eternal truth, which we cannot, it seems as though science cannot be trusted. If we cannot rely on language or science to exact eternal truth, we can only conclude that the B-theory does not provide claims that are true eternally. The claims made within the B-theory are sempiternal at best. Smart’s B-theory does not satisfy premise (3) and is therefore not real on its own terms.

This sempiternity is to be crucially distinguished from the A-theories sempiternity. In the A-theory, truth is relative to a particular person making a claim. It is therefore not objective and does not go beyond our cognitive activities (it does not meet premise (2)). Smart’s B-theory does meet premise (2), it does provide us with truth that is not relative to our cognitive abilities. The truths in the B-theory are relative to a particular conceptual or linguistic scheme.

Conclusion

On Smart’s B-theory’s own terms, it is not real. We could conclude from here that neither the A-theory nor the B-theory are real, and therefore that time is unreal. But, given that no theory of time can ever hope to achieve eternal truth, I believe it is the proper choice to reject premise (3). Theories of time ought not aim toward eternal truth. To believe that one’s particular linguistic or conceptual scheme or one’s scientific paradigms constitute eternal truth is to place an unfair primacy on one’s particular mode of thought and way of being. This is incredibly egocentric and anthropocentric, which is what we are trying to avoid in the first place. We ought to be wary of our epistemological limitations and concede that we are not equipped with the tools to fully understand reality in terms of time if such a thing is even possible. Allowing for this plurality of thought allows for non-dominant voices to properly express their understandings of time relative to their particular conceptual or linguistic schemes. We ought to prefer this as opposed to aiming for eternal truth for fear of stifling marginalized thought and coherent ideas surrounding time.

Rejecting premise (3), that leaves only premise (1) and premise (2). The A-theory does not meet premise (1) or premise (2). Put differently, the A-theory can be said to exist but does not exist independently of our cognitive activities. Smart’s B-theory meets premise (1) and premise (2) in that it exists and exists independently of our cognitive activities. Therefore, Smart’s B-theory is real and the A-theory is not. The stipulation that follows from this conclusion is that Smart’s B-theory should be wary of its epistemological limits and should not aim toward eternal truth.

References

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