PRESENTIST RESPONSES TO THE TRUTHMAKER OBJECTION

Marc Bohler

’17, Covenant College

Abstract:

In this paper, I discuss the implications of the truthmaker objection on various forms of presentism. I conclude that this objection is sufficient to defeat certain forms of presentism that deny that future contingent truths can be either true or false in the present. However, I argue that the objection is insufficient to defeat presentism generally, and specifically, that it does not defeat at least one form of presentism that recognizes God’s foreordination as a truthmaker.

Paper:

Advocates of presentism frequently claim that it is the most intuitive theory about time. Yet, their opponents point to what they see as rather unintuitive implications of the belief that past and future do not exist. One frequently – offered objection against presentism is known as the truthmaker objection. It asks: what can serve as a truthmaker for sentences referring to a past or future event if the past and future do not exist? While presentist discussion of this topic in the past has resulted in a wide variety of responses, many of these responses have not adequately addressed the problems raised by the truthmaker objection. However, if we are willing to be reasonably permissive with what counts as a truthmaker, presentists potentially have at least one valid response at their disposal.

Naturally, it is important to have a clear understanding of what counts as a presentist theory in this discussion. Alan Rhoda, who wrote a paper with a purpose very similar to this one, began his discussion with the definition of presentism as “…the metaphysical thesis that whatever exists, exists now, in the present.”[1] However, this definition might be considered too restrictive by some who would call themselves presentists. A somewhat more permissive definition is given by Hobbes in Leviathan. “The Present onely has a being in Nature; things Past have being in the Memory onely, but things to come have no being at all.”[2] This definition is not so clearly opposed to the existence of atemporal existents. It is my view that those who believe that the present does exist, but that the past and future do not, should be allowed into the general body of presentists even if they accept the existence of objects outside time and space. Thus, I will allow for all theories that agree with the statement: all temporal existents exist in the present and only in the present. This change in definition is a substantive change because I intend to argue that the strongest response that the presentist has to the truthmaker objection is one which fits in this permissive definition, but would not be allowed under Rhoda’s definition.

A second definitional concern is how we should understand the truthmaker objection itself. Rhoda offers a succinct summary of the problem. The truthmaker principle is defined as:

(TM)     Every truth requires a truthmaker, an existing state of affairs (or ‘fact’) that necessitates and thereby grounds its truth.[3]

“If we combine TM with presentism,” Rhoda argues, “…we get the result that every truth needs to be grounded in some presently existing fact….”[4] The truthmaker problem is that it is not clear what presently existing fact could explain the truth of a statement about a past or future event. For example, if I say “St. Augustine was a presentist,” a nonpresentist would simply say that what makes this claim true is the fact that St. Augustine was indeed a presentist. This is allowed for the nonpresentist because the past, with St. Augustine in it, exists in his or her ontology. For the presentist, however, this is apparently problematic since St. Augustine does not exist in the present (assuming St. Augustine is equivalent with his body, a claim to which he might take offense).

Rhoda then takes it to be the case that what is needed for the presentist is something that exists in the present but has truthmaking power for the statement about the past because it is an effect of the past fact (in this example, the past fact being that St. Augustine was indeed a presentist).[5] The bulk of Rhoda’s article is concerned with setting requirements for what such a truthmaker should look like. The first requirement is that “[t]he truthmaker for a truth about the past must be an effect or trace of the past facts or events it refers to.”[6] Rhoda’s primary concern is truthmakers for statements about the past. He does not intend to offer a second truthmaker for statements about the future, and it is not clear in his argument that he thinks one actually exists. Many presentists argue that, in fact, no truthmaker for the future does exist.[7] Contingent statements about the future simply remain indeterminate until the future becomes present, at which point they will become either true or false. This discussion is heavily influenced by Aristotle’s discussion about future claims in On Interpretation.

Aristotle argues that there are necessary truths about the future as well as contingent truths. Many have argued that necessary truths about the future, unlike their contingent counterparts, do not require truthmakers. If this is correct, then we do not need to justify these sorts of necessary truths. But we still need to account for future contingent truths. Aristotle thinks that contingent statements about the future are indeterminate in the present. Then later, when the future becomes present, the truth value will become assigned to the statement.[8] Aristotle uses a sea fight as an example. He argues that the statement “either a sea fight will occur tomorrow or it will not” is true in the present because of the law of noncontradiction. But the assertion that “a sea fight will occur tomorrow” as well as the alternate assertion that “a sea fight will not occur tomorrow” both have an indeterminate truth value in the present.[9]

In his analysis of how Aristotle’s system of future contingent truth applies to presentism, Craig Bourne offers a truth table definition of Aristotle’s logic:[10]

 ~ & T ? F T ? F
T F T T ? F T T T T
? T ? ? ? F ? T ? ?
F T F F F F F T ? F

If we accept Bourne’s interpretation as the correct way to think about future contingent statements, it seems to present a problem for presentists like A. N. Prior who agree with Aristotle that future contingent statements are not true or false in the present, but will be made so in the future.[11] If we agree with Prior and the ancient view about contingent truth that “…the statement ‘Socrates is sitting down’ is true so long as he is sitting down, but becomes false when he gets up,” and we also agree with Bourne, then it seems that we would agree that the truth value of:

(p)       There will be a sea fight in the future.

is indeterminate in the present. But we would also be forced to agree with the claim that:

(q)       (p) will be made either true or false in the future.

But this presents a problem for the presentist (as well as the growing-block theorist). Statement (q) is not necessarily true. For it is possible that the truth value of (p) will remain indeterminate in the future. Now some of my more observant readers who know Aristotle’s works might accuse me of duplicity, and they would be correct. Where Aristotle talks about a sea battle occurring or not occurring tomorrow, I have switched it out with the vaguer question of whether or not it will occur at an unspecified time in the future. This is because I think that Aristotle’s claim is in fact necessary, but my alteration is not.

The obvious response of the presentist to my claim that (q) is not necessarily true is that it is equivalent with the law of excluded middle. However, if you will indulge me in a thought experiment, I think I can show they are not equivalent. In Aristotle’s example, he asks whether a sea battle will occur tomorrow, and indeed, at the end of tomorrow we (or at least God) will have the answer of whether it has or has not occurred. Thus, I think it is fair to conclude that if we limit our statements to specified points in time, we can say that if we have the claim:

(p*)     There will be a sea fight tomorrow

then it is necessarily the case that:

(q*)    (p*) will be made either true or false tomorrow

But suppose we assume that the universe we live in will continue on infinitely existing in time. If at any time, there is in fact a sea battle after we have made statement (p), then of course statement (q) has been shown to be correct. However, suppose a sea battle does not occur. The presentist admits that we would not be able to claim (p), and we similarly would not be able to claim (~p). Therefore, we would never be able to claim that (q) is true. The presentist might at this point simply dig-in his or her heels and insist that regardless of whether we know a sea fight will or will not happen, there is a metaphysical truth about whether it will or will not. But statement (q) does not leave this response open. If (p) never occurs, then the presentist has no right to claim that (q) will become determinate, because doing so would require deciding whether (p) will happen or will not happen.

Finally, the presentist might object that he or she can simply reject my claim that the universe is temporally infinite. In fact, I would agree with him or her that it is likely not temporally infinite, but this does not limit the force of the argument. The question is whether or not (q) is necessary, not whether it is likely to be true. It seems reasonable to say that it is not necessary that the universe be temporally finite, and therefore, my example still demonstrates conclusively that statement (q) is not necessarily true. In other words, my thought experiment is a possible world, and in this possible world, (p) might have an indeterminate truth value indefinitely.

If (q) is not necessarily true, then a truthmaker is required for its truth. Thus, we can come to this conclusion:

Presentists like Prior claim that

(r)       Propositions about future contingent truths are neither true nor false in the present.

 Instead, they claim

(s)      Future contingent claims will be made either true or false in the future.

 However, given the preceding argument:

(t)       (s) is a future contingent claim.

    ∴ (u)      (s) is not true or false in the present.

The implication of this is that this particular form of presentism which denies the truth or falsehood of future contingent claims in the present, as represented by Prior, is neither true nor false on its own terms.

Returning to Rhoda, if we conclude that he agrees with Prior that statements about the future are indeterminate in the present and determined in the future, then he will run into this same issue. However, if we give Rhoda the benefit of the doubt and assume he knows of some present truthmaker for future contingent claims, we can examine his solution to the truthmaker objection about past statements without concern. In short, his solution is that the truthmaker of a past claim is a memory in the mind of God. Memories of the past exist in a presentist ontology, and God’s memory is perfect. Thus, on the surface, this solution seems to satisfy Rhoda’s criteria for a truthmaker. However, Ben Caplan and David Sanson object to Rhoda’s solution:

….when it comes to explaining the truth of the proposition that Plato had a beard, Rhoda’s account points to the wrong thing: his account points to a memory in the mind of God, but a memory in the mind of God doesn’t explain why the proposition that Plato had a beard is true. God remembers that Plato had a beard for the same reason that the proposition that Plato had a beard is true: because Plato had a beard. But it is not because God remembers that Plato had a beard that the proposition that Plato had a beard is true.[12]

In other words, Caplan and Sanson believe that a memory in the mind of God is not a sufficient option for a truthmaker because the truthmaker for the claim that God has a memory of some event is that that event actually occurred. Thus, if we do not have access to the truthmaker that the event really did occur (as the presentist does not), we cannot use God’s memory as a truthmaker.

Rhoda responds to a similar objection by saying that it rests on a confusion between truthmakers and truth conditions.[13] God’s having a memory of an event is entailed by the fact that the event really happened. But the relationship of entailment is not the same relationship as truthmaking. Thus, in response to this objection, Rhoda argues that:

That God remembers E means that God knows that E happened. Clearly, the proposition ‘God knows that E happened’ cannot be true unless it is true that E happened, as the latter is a truth condition of the former. Equally clearly, and consistent with this, is that the fact that makes it true that God knows that E happened also makes it true that E happened.

It still is slightly surprising that there is a different truthmaker for the claim that “E happened” than there is for the claim “E is happening,” but there does not appear to be any legitimate inconsistency in this claim. If we take this to be sufficient proof that Rhoda is correct, we may be willing to allow for a memory of God as being a sufficient truthmaker. However, we are still left with the problem of future contingent truthmaking. Again, it is possibly true that there is some other truthmaker for future claims that Rhoda simply does not mention. However, it is not easy to see what one might be under his system.

But there is another option that seems to deal better with the problem of future contingents because it allows that statements about the future are already true in the present. If instead of God’s memories, we appeal to God’s foreordination of events as a truthmaker, we can evade the infinite regress resulting from statements about future contingents.[14] In order to accept this possibility, however, we will have to adjust Rhoda’s system. First, we will have to accept the definition of presentism offered at the beginning of this discussion allowing that God can be seen as existing atemporally. Second, unless we intend to offer a second truthmaker for past truths, we will have to reject Rhoda’s first requirement for a truthmaker about the past, where he claims “[t]he truthmaker for a truth about the past must be an effect or trace of the past facts or events it refers to.”[15] Rhoda offers a convincing argument for this requirement:’

….whatever makes it true that, say, Caesar was assassinated, needs to be somehow tied to the past event of Caesar’s being assassinated, for had that event not occurred it simply wouldn’t be true that Caesar was assassinated. Thus, the presentist needs to make a distinction between the historical ground of a truth about the past (i.e. the past fact or event it refers to) and its metaphysical ground (i.e. the present fact that serves as its truthmaker), and she needs to say that the latter has the character it does because the former had the character it did.[16]

In short, Rhoda is arguing that if a past event does not occur, then a statement claiming that it did will not be true regardless of the truthmaker you offer to say that it will be. Thus, Rhoda thinks that any truthmaker offered must have a causal tie to the original fact that makes it necessarily the case. But it appears that Rhoda may have skipped over the possibility that this tie could be prior to the original fact – a cause of it rather than an effect. Since most theists who accept foreordination would hold the belief that if God foreordains an event, then it will come to pass, foreordination seems to fit the role of a truthmaker. God’s foreordination would also be a truthmaker for statements about present truths and future truths, unlike memories. This view also has the minor added benefit of avoiding Caplan and Sanson’s objection altogether because God’s foreordination, being the cause of Plato having a beard, does explain why Plato has a beard.

It seems to me that there could be several reasons for arguing that God’s foreordination does not fit within the normal definitions of truthmaking. However, in my examination of what a sufficient truthmaker should be like (which was primarily focused on Rhoda’s and Caplan/Sanson’s conditions), I did not find a satisfactory condition that excluded this option. The only condition that seemed to offer any argument against it was Rhoda’s first requirement. But as I have explained, this condition seems to ignore the possibility of any kind of tie to a past event that is not an effect.

Thus, the truthmaker objection to presentism does appear to weed out several variations of presentism including the view that present claims are indeterminate until they are made true or false in the future. However, it does not appear to succeed in eliminating presentism as a viable metaphysical theory about time as long as one is willing to have a reasonably permissive view of what a truthmaker can be.


[1] Alan R. Rhoda, “Presentism, Truthmakers, And God,” Pacific Philosophical Quarterly 90, no. 1 (March 1, 2009): 41.

[2] Thomas Hobbes, Leviathan, ed. J. C. A. Gaskin, (Oxford: Oxford University Press, 1998), 22.

[3] Rhoda, “Presentism, Truthmakers, And God,”  41.

[4] Ibid.

[5] Ibid., 43.

[6] Ibid.

[7] A. N. Prior, “Some Free Thinking about Time,” in Metaphysics: The Big Questions, ed. Peter Van Inwagen and Dean W. Zimmerman (Malden, MA: Blackwell Publishing, 2008), 161-164.

[8] Aristotle and Richard McKeon, On Interpretation, in The Basic Works of Aristotle (New York: Random House, 1941), 45-48.

[9] Ibid., 48.

[10] Craig Bourne, “Future Contingents, Non-contradiction, and the Law of Excluded Middle Muddle,” Analysis 64, no. 282 (April 2004): 125.

[11] Prior, “Some Free Thinking about Time,” 161-162.

[12] Ben Caplan and David Sanson, “Presentism and Truthmaking,” Philosophy Compass 6, no. 3 (2011): 12.

[13] Rhoda, “Presentism, Truthmakers, And God,” 55.

[14] This solution was offered by my professor at Covenant College, Dr. John C. Wingard.

[15] Rhoda, “Presentism, Truthmakers, And God,” 43.

[16] Ibid.

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