Do Past-Tensed Truths Need Truthmakers?

Cyrus wrote in an earlier thread,

In the linked article, you write:

That (some) truths refer us to the world as to that which makes them true is so obvious and commonsensical and indeed 'Australian' that one ought to hesitate to reject the idea because of the undeniable puzzles that it engenders. Motion is puzzling too but presumably not to be denied on the ground of its being puzzling.

But I question whether the scope of the “some” (that is, the scope of the obviousness and commonsensicality) extends to past tensed truths. I don't find it obvious that past tensed truths have truthmakers. Presumably presentists who reject it also don't find it obvious. (Some find it obvious that the past doesn't exist.) I guess what I'm asking is: Is there an objective way to measure obviousness? If there isn't, how much should we really be relying on it in our arguments?

That's a good comment and a good challenge. As Hilary Putnam once said, "It ain't obvious what's obvious."  So I don't think there is any objective way to measure obviousness, or, to use a better term, objective self-evidence. Nevertheless, I will die in the ditch for the first of my italicized sentences above. Surely there is at least one truth that cannot just be true, but needs a truth-ground that exists and indeed exists extramentally and extralinguistically. For example, 'BV is seated.'  That cannot just be true. It cannot be a brute truth. I have gone over this so many times I'm sick of it.  So let's move on.

Cyrus supra is not questioning whether there are truthmakers, nor is he raising the question as to the nature of truthmakers, i.e., the question of the category of entity to which they belong (Armstrongian states of affairs? tropes? etc.); he is raising the question whether past-tensed truths need truthmakers. I grant that the answer is not obvious.

One thing we should be clear about is that presentists needn't deny that past-tensed truths need or have truthmakers.  For they could hold, as some have held, that these truthmakers exist at present.  On presentism, whatever exists in time exists at the present time.  This is not the tautology that whatever exists (present tense) exists (present tense). This trivial truth is contested by no one. What the presentist is maintaining is that only what exists (present tense) exists tenselessly.  Presentism about what exists  in time is a restrictionist thesis: it restricts what tenselessly exists in time to what presently exists, i.e. what exists at present, or now.  (Note the ambiguity of 'presently' in ordinary English: if I say that I will visit you presently, that means in ordinary contexts that I will visit you soon, but not now.)

So we can divide presentists who accept truthmakers in general into two groups. Group One is composed of those who hold both that some past-tensed and some present-tensed truths have truthmakers, and Group Two is composed of those who accept that there are past-tensed truths but hold that they are all brute truths.

This is the view that I will try to argue against.  But first we need to lay another assumption on the table

I assume that there are past-tensed truths. For example, I assume that it is true, and indeed true now, that JFK was assassinated and that Socrates taught Plato.  (But don't get hung up on these examples: I could use different ones.) One might deny these (datanic) points in two ways. One could assert that all past-tensed truth-bearers are false. Or one could assert that no past-tensed truth-bearer is either true or false. For now we set these (lunatic) views aside.

The assumption, then, is that there are past-tensed truths.  The question is whether any of them need truthmakers given that present-tensed truths need truthmakers.

It is contingently true that I am alive. This is not a brute truth. Its truth requires, at a minimum, the existence of the living animal that wears my clothes. It is also true that after I am dead it will be true that I was alive today. If the first truth is not brute, how could the second truth be brute? The first truth is about me. It says that BV is alive. The second truth is also about me. It says that it will be the case that BV was alive. Now a proposition cannot be about a thing unless the thing exists. So in both cases the thing, me, exists. So both truths are grounded by my existence. If <I  am alive> asserted by me today has an ontological ground, and it clearly does, then <BV was alive> asserted after I am dead by a descendant also has an ontological ground. The two propositions differ merely in tense. Does that difference make a difference with respect to truth-making? It is not clear that it does. It is plausible to hold, with T. Merricks, that if presentism is true, then all truths about wholly past items are brute truths. Should we affirm the antecedent and infer the consequent by modus ponens? Or should we deny the consequent and deny the antecedent by modus tollens? It is not clear. The arguments appear to be equally good and cancel out. This is so given that the truth-makers of past-tensed truths about wholly past items cannot be located in the present. Perhaps some can be so located, but not all.

My interim conclusion is that presentism  is open to serious objection.  The fact that 'eternalism' is also is no good reason to accept presentism.

Comments

[OZ]

“What the presentist is maintaining is that only what exists (present tense) exists tenselessly.”

One possible meaning for ‘X exists tenselessly” means “X is or was (or will be?) something”. If so, why would anyone hold that everything that exists tenselessly, exists in the present?

Presumably the anti-presentist denies that meaning, but the correct meaning needs to be made clear.

FYI my friend Magali Roques recently wrote on the medieval theory of natural supposition, “the mode of reference that a term has when the proposition in which it occurs as a subject term causes it to be taken for all its significates regardless of the tense of the proposition”.

[Cyrus]

Bill,

What are propositions on presentism? Do they exist in time? If not, it's not even true on presentism that “BV is alive”. If so, propositions might have to be contingent, and it might be possible that “BV was alive” is neither true nor false (e.g. if propositions are mental and nobody is thinking it).