Friday, November 25, 2011

The truthmaker for 'Socrates exists'

No one agrees, so let’s look again at the premiss (3) of my earlier argument. I claim that the truthmaker for ‘A exists’ is not A itself. I argue as follows. If Socrates himself is the truthmaker for ‘Socrates exists’ then, from the definition of truthmaker, Socrates makes the proposition ‘Socrates exists’ true. But that is manifestly false, given that Socrates no longer exists. I.e. the proposition

(*) Socrates makes the proposition ‘Socrates exists’ true

is manifestly false. For he cannot make that proposition true unless it is true. But it is false. Socrates no longer exists, so ‘Socrates exists’ is false. So Socrates does not make the proposition ‘Socrates exists’ true, and therefore, by the definition of truthmaker, Socrates himself is not the truthmaker of ‘Socrates exists’.

41 comments:

J said...

Re-- ancient/historical persons-- their existence can't be confirmed, really. Highly probable (Soc. mentioned in other sources, etc), but thats another issue (verification, more or less).

-- Though in "real time" (rather than ancient history) ...perception of an object (event/state of affairs) is a necessary condition of "ordinary" inductive/empirical arguments. And that's what Armstrong means by a Truthmaker. IMO (ie, a smoking gun with X's fingerprints in a murder case, where X is charged with murder). NO? Then what is it.

Anthony said...

A is the truthmaker for "A exists" if and only if A exists.

Truthmakers do not exist for false propositions.

Anthony said...

In any case, are you taking a presentist or anti-presentist view? You seem to be mixing the two, taking a presentist view of "A exists" but an anti-presentist view of "makes true".

J said...

Gosh golly.

have you read David Armstrong's essay yet, or the Wiki, or maybe a paragraph on Truthmakers? Good place to start, "Ant.".

Without a human to perceive it, the "Truthmaker" wouldn't be known---.

Edward Ockham said...

>>Truthmakers do not exist for false propositions.

Ergo, Socrates himself is not the truthmaker for 'Socrates exists'. Glad you have finally nailed this point.

Edward Ockham said...

>>have you read David Armstrong's essay yet, or the Wiki, or maybe a paragraph on Truthmakers? Good place to start, "Ant.".
<<

This violates my comments 101 policy, J. If you are referring to some view which you think another commenter has misunderstood, say what the view is, and say why you think the other commenter has misunderstood it.

Comments should be self-citing, as it were.

Edward Ockham said...

>>In any case, are you taking a presentist or anti-presentist view? You seem to be mixing the two, taking a presentist view of "A exists" but an anti-presentist view of "makes true".
<<

No. On the presentist view, 'Socrates makes 'Socrates exists' false', the reading of both 'makes' and 'exists' is presentist.

Perhaps you mean that I am using the term 'Socrates' to refer to a non-existent individual. This is perfectly consistent with my presentism.

Anthony said...

>> Ergo, Socrates himself is not the truthmaker for 'Socrates exists'.

If by "exists" you mean "exists currently", sure.

>> Glad you have finally nailed this point.

I still don't get it. There are some propositions for which truthmakers don't exist. No one is making a claim otherwise.

But you seem to be making a claim that no truthmakers exist. To show that you are wrong, a single counterexample is sufficient.

So your points about false propositions, and your points about future-tensed or past-tensed propositions, and any points you would make about negative propositions, or propositions about abstracts, or any other difficult (or impossible) cases, are irrelevant.

That the sun exists is a true proposition. And the sun is the truthmaker for that proposition.

J said...
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J said...

Vallicella is not presenting D. Armstrong's views on Truthmakers correctly, if at all. So you're attacking a fiction, and missing out on most of his ideas (including the obvious problem of historical verification).

You're not a muslim, are you? They really hate Randians.

And as usual you ignored a difficult issue--the necessity/sufficiency issue. Observation of an object would be necessary for certain...evidential claims (whether in legal, scientific or journalistic contexts). But perhaps not sufficient. Would take some explaining ..but a gun thought to be used in a crime might turn out to be wrong. At any rate the gun was necessary for the charges/trial.

I would say there's ..a constructivist point as well .But it's probably a bit complex for you, since you tend to favor T or F. (ie, rules of evidence themselves part of a social contract, etc)

Edward Ockham said...

>>I still don't get it. There are some propositions for which truthmakers don't exist. No one is making a claim otherwise.

The claim I am trying to undermine here is the claim that Socrates himself is a truthmaker for 'Socrates exists', not the claim that there are no truthmakers.

>>But you seem to be making a claim that no truthmakers exist. To show that you are wrong, a single counterexample is sufficient.
<<

I am inferring that as the conclusion of an argument, one of whose premisses is 'Socrates does not make 'Socrates exists' true'. See the previous post, which I even linked to in this post.

Look at the previous post and see if you agree that the argument is valid - note that an argument can be valid even with all its premisses false. Then look at the premisses, etc etc.

Anthony said...

>> On the presentist view, 'Socrates makes 'Socrates exists' false', the reading of both 'makes' and 'exists' is presentist.

You're not saying that Socrates makes "Socrates exists" false, are you?

>> Perhaps you mean that I am using the term 'Socrates' to refer to a non-existent individual. This is perfectly consistent with my presentism.

Well, now that you make that clear, I think I understand what you're saying. But I still don't see the problem. Let me summarize:

A current-truthmaker is an entity that currently-makes a proposition like ‘Socrates sits’ currently-true.

If Socrates himself is the current-truthmaker for ‘Socrates exists’ then, from the definition of current-truthmaker, Socrates currently-makes the proposition ‘Socrates exists’ currently-true.

But that is currently-false, given that Socrates does not currently-exist. For he only currently-makes that proposition currently-true when it is currently-true.

But it is currently-false. Socrates past-existed, but does not currently-exist, so "Socrates exists" is currently-false. So Socrates does not currently-make the proposition "Socrates exists" currently-true, and therefore, by the definition of truthmaker, Socrates himself is not the current-truthmaker of "Socrates exists".

Anthony said...

>> The claim I am trying to undermine here is the claim that Socrates himself is a truthmaker for 'Socrates exists', not the claim that there are no [sic] truthmakers.

Who made that claim?

>> Look at the previous post and see if you agree that the argument is valid - note that an argument can be valid even with all its premisses false.

Well, I don't really understand the argument. It seems to me that it amounts to:

1) There are truthmakers (assumption)
2) If Not-P, then there is a contradiction (by infinite, vicious regress)
3) Not-P.
4) (Contradiction) Therefore there are no truthmakers

which amounts to:

1) There are truthmakers (assumption)
2) P.
3) Not-P.
4) (Contradiction) Therefore there are no truthmakers

Edward Ockham said...

>>which amounts to:

1) There are truthmakers (assumption)
2) P.
3) Not-P.
4) (Contradiction) Therefore there are no truthmakers

The 'P' of this version is different from the 'P' of the summarised argument.

There is also a enthymematic premiss in my argument, namely that if there are truthmakers, 'A exists' has a truthmaker. This is either A itself, or not. If not A itself, this leads to a contradiction. But it is not A itself etc etc.

J said...

A different issue, Ock. ("maximalism"--which D Armstrong discusses). Is BV saying...for any "truth" whatsoever, a Truthmaker exists?? In that case, Im not sure...I would agree. How about "Hitler is Evil"? Or "Laissez faire economics doesn't work." Or..."the Beegees suck"??? Etc. So, were you engaging D. Armstrong's entire argument you'd run into that.

Edward Ockham said...

>>Is BV saying...for any "truth" whatsoever, a Truthmaker exists??

I think he is saying that for any present tense proposition, a truthmaker exists.

David Brightly said...

OK, I'll bite. Bill's working definition is that entity T is the truthmaker of p iff the proposition 'T exists' entails p. So what's the truthmaker of 'Vallicella exists'? Formally, it looks to be the entity Vallicella, because substituting Vallicella for T in 'T exists' gives a proposition that does entail 'Vallicella exists'. This is superficially convincing. What do you think is wrong with this argument? Let's not get sidetracked into presentism or 'tenseless existence'.

Anthony said...

>> The 'P' of this version is different from the 'P' of the summarised argument.

It doesn't matter. Your premise (2) contradicts your premise (3). You even seem to admit this.

>> There is also a enthymematic premiss in my argument, namely that if there are truthmakers, 'A exists' has a truthmaker.

For all A? For some A?

First of all, the proposition that A exists only has a truthmaker if A exists (or, under your brand of presentism, only has a truthmaker when A exists). If you are going to allow A to refer to "non-existent things" (I have to put it in quotes because I find it so absurd), then your premise does not hold for all A.

Secondly, I think you are confusing the truthmaker principle (*), which neither Vallicella nor I agree with with, with the concept of a truthmaker.

(*) If φ , then there is an x such that necessarily, if x exists, then φ .

Anthony said...

"I think he is saying that for any present tense proposition, a truthmaker exists."

I believe he has stated that he believes that truthmakers exist for any "contingently true proposition". However, he is starting out by trying to show that they exist for at least some "positive, present tense, contingently true, propositions".

Anthony said...

>> Bill's working definition is that entity T is the truthmaker of p iff the proposition 'T exists' entails p. So what's the truthmaker of 'Vallicella exists'?

Isn't a more accurate definition, at least if one is going to allow references to "non-existing entities", that entity T is the truthmaker of p iff the proposition 'T exists' entails p, and p?

Do false propositions have truthmakers? Is a unicorn the truthmaker for "A unicorn exists"? I suppose Vallicella would say that this is not even a proposition, though I suppose Ed would say that it is.

Edward Ockham said...

OK, I'll bite. Bill's working definition is that entity T is the truthmaker of p iff the proposition 'T exists' entails p.

>>What do you think is wrong with this argument?

The first thing wrong is the 'symmetry problem'. We agreed that Vallicella himself can't be the truthmaker of 'Vallicella runs'. So why should the verb 'exists' be different? Arguing that existence is not a predicate is wrong, because the verb 'exists' clearly is a predicate. We are asking about the status of the verb 'exists', not about the status of some abstract thing 'existence', if there is such a thing. #

The second thing wrong is that this definition does not eliminate spurious truthmakers, such as the sunrise causing day. The sun is out (i.e exists) iff it is day. But the sun is not the truthmaker of 'it is day', according to Vallicella. It is not enough for the existence of T to be a necessary and sufficient condition of the truth of p. There needs to be a proximate and direct connection that I fail to understand.

>>Let's not get sidetracked into presentism or 'tenseless existence'.

I don't think that is a sidetrack.

David Brightly said...

I don't think the sun is a spurious truthmaker 'for it is day' under the working definition for 'it is day' because 'the sun exists' does not entail 'it is day'---it might be night. Can we stick with this definition regardless of whether it captures our intuition as to what truthmaking might be? And we agree that Vallicella is not the truthmaker of 'Vallicella exists'---nothing is, so we don't need to reiterate the symmetry argument.

Neither of us thinks truthmaking makes sense so there must be something badly wrong with the definition, perhaps in the same way as the 'definitions' in the Barber paradox or Grelling's paradox. However it seems to convince Bill and Peter. Can we put our finger exactly on the problem?

J said...

You mean like..an existential generalization that any 2nd year logic student would use, DB? (ie backwards E"(x)")

Within a domain (say, Arizona)== Ex V(x) "there exists a person X named Vallicella" . Ergo, BV would be the Truthmaker

Google time Ant!

Edward Ockham said...

>> Can we stick with this definition regardless of whether it captures our intuition as to what truthmaking might be?
<<

Now you've lost me.

Anthony said...

>> We agreed that Vallicella himself can't be the truthmaker of 'Vallicella runs'. So why should the verb 'exists' be different? Arguing that existence is not a predicate is wrong, because the verb 'exists' clearly is a predicate.

Well, it is in the sense that you are using it (basically, "exists" = "exists currently"). But not in the sense that Vallicella is using it (where "exists" = "is a valid subject of a proposition").

My understanding is that Vallicella's use is more typical, but I don't think I can say that your use is wrong. In fact, you've got me wondering if maybe Vallicella's use is the wrong one.

With that said, however, I think the notion of "truthmaker" can be adapted to your use of "exists".

David Brightly said...

Sorry, hasty response. The idea is this. We may not understand the nature of truthmaking but Bill gives us a rule for finding a truthmaker for any proposition p, viz, any entity t such that 't exists' entails p will do the job. So we have an 'equation' to solve. When p = 'Vallicella exists' a solution would appear to be t = Vallicella. Bill is persuaded by this reasoning, but if you are right about truthmaking it must be flawed. It would be especially convincing if we were able to expose the flaw. I make a stab at it here.

J said...

It's not entailment, but just basic instancing, EG:..."There exists an X named Vallicella." Though Armstrong's book goes into many other issues (ie, what of induction, indirect evidence, probability, etc). OK deny knowledge via sense impressions altogether (as Frege..mostly does in the Gedanken essay). But thats another issue (ie, metaphysics, more or less). Ordinary claims require reference to an object (ie, seeing that Rush is obese, to say..yes, Rush is obese, or "there exists an X named Rush who is obese", falls in class of obese).

It's hardly as mysterious as you make it, Brightly.

Edward Ockham said...

David >>any entity t such that 't exists' entails p will do the job.
<<

I'm worried about that. In Ockham world 'any entity' ranges only over existing entities. Brentano equivalence, you remember. Are you saying that a truthmaker for a proposition is anything such that if it exists, p is true?

Also, the asymmetry means that if T is the truthmaker for 'sun is shining', it is also a truthmaker for 'T exists'. So every truthmaker makes at least two propositions true, namely the p it makes true (e.g. 'sun is shining'), plus the proposition that asserts its own existence.

It may not be a fatal flaw, but it is messy. (Which to nominalists and desert-lovers, is a fatal flaw).

Anthony said...
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Anthony said...
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Anthony said...

"So every truthmaker makes at least two propositions true"

Only if you're a Platonist with respect to propositions.

And even then, only if you assert that two sentences which mean the exact same thing are two propositions, and not one.

Edward Ockham said...

>>And even then, only if you assert that two sentences which mean the exact same thing are two propositions, and not one.

True.

Edward Ockham said...

>>Only if you're a proposition-realist.

But truthmakerists are proposition realists.

David Brightly said...

>> Are you saying that a truthmaker for a proposition is anything such that if it exists, p is true? <<

Not quite. There's a modal element. The 'proximate and direct' connection you seek is some sort of necessitation. t is a truthmaker for p only if in every world in which t exists, p is true. I can't for the moment find a post where he casts this in stone but here's a quote from Truthmaker Maximalism Questioned which gets the spirit.

Argument from Necessitation.  Assume for reductio that Peter by himself can serve as truthmaker.  Now, by Truthmaker Necessitarianism, whatever truthmakers are, they broadly logically  necessitate the truth of their corresponding truthbearers.  So if X is the truthmaker of *Peter is tired at t,* then there is no possible world in which X exists and *Peter is tired at t* is not true.  But there are plenty of worlds in which Peter exists but *Peter is tired at t* is not true.  So Peter by himself cannot be the truthmaker of *Peter is tired at t.*

This is what rules out Vallicella as truthmaker for 'Vallicella is sitting'. Bill claims that the tm of the latter is the entity 'Vallicella's being seated'. Though we use such phrases as subjects in sentences we don't normally think to quantify over them.

Bill's tm rule seems to work 'formally', as it were, by substitution of words into sentences. I can't make sense of it otherwise. And I agree it's messy. This cuts no ice with the Phoenicians, of course.

J said...

That's the usual problem the nominalists here overlook.
Does a class of Obesity exist? How about mammals? Triangles? We say Yes, without thereby endorsing big P Platonism (perhaps the classes are not a priori but mindmade, or constructed. Either way, "Rush is Obese" is meaningful, as are many other adjectivals. Verbs make things a bit more difficult...but merely a different sort of class--ie, horses belong to a class of animals who can run (gallop, stride, etc).

Anthony said...

>> But truthmakerists are proposition realists.

What in the definition of truthmaker entails proposition-realism?

Anthony said...

>> Bill's tm rule seems to work 'formally', as it were, by substitution of words into sentences. I can't make sense of it otherwise.

Well, for starters, do you agree that, when Vallicella is seated, Vallicella's being seated exists?

If not, what does exist?

Edward Ockham said...

>>What in the definition of truthmaker entails proposition-realism?

I’m not sure. My point was that truthmakerists tend to be proposition-realists.

>> Bill's tm rule seems to work 'formally', as it were, by substitution of words into sentences. I can't make sense of it otherwise.

I have the same problem.

>> Well, for starters, do you agree that, when Vallicella is seated, Vallicella's being seated exists? If not, what does exist?

As discussed before, I hold that “Vallicella is seated”, “’ Vallicella is seated’ is true”, “it is true that Vallicella is seated”, “Vallicella's being seated is a fact”, “Vallicella's being seated is the case”, “Vallicella's being seated exists” etc are all different ways of saying the same thing. So, yes, I agree that Vallicella's being seated exists when Vallicella is seated, though it is an odd an idiosyncratic way of saying it.

Anthony said...

>> My point was that truthmakerists tend to be proposition-realists.

Well, "tend to be" isn't sufficient to use it as an assumption when disproving truthmakerists.

>> So, yes, I agree that Vallicella's being seated exists when Vallicella is seated, though it is an odd an idiosyncratic way of saying it.

I'm surprised you agree with that. I thought you complained earlier about wanting a picture.

It certainly brings up the question of, if "Vallicella's being seated" can exist, what is it? But maybe this is getting off topic?

Edward Ockham said...

>>"Vallicella's being seated" can exist, what is it? But maybe this is getting off topic?
<<

It's an interesting subject but, yes, slightly off-topic.

J said...

Does a class/group/universal "mammalness" exist or not, Ock. (or obesity, "triangleness", etc). It would seem that if you grant the class, you would have to assume there are individuals in the class (ie, jaguars are mammals). And the objects are "truthmakers" in Armstrong-Speak (tho, granted the terminology's a bit weird---but were one to see a jag. say in south AZ-land, one might say there is a causal relation--see it--via yr handy Bushnells' scope, and you say, lo,a jaguar (and write it down later..jag sighted, etc). Seeing it made it true).