Can you expand on this "modal actualizer" thing? — Wallows

In some modal logics, a world is set aside in the frame, to be the distinguished 'actual world,' sometimes symbolized @. An operator that means 'actual' then operates on a formula to make it true at any world just in case the formula it operates on is true at @.

If you write this as 'actual,' then 'the actual president of the US' denotes Donald Trump, not just at the actual world, but at any world. So, it is a rigid designator.

But this is a technical device, since the English word 'actually' doesn't work this way.

A description can be a rigid designator, if its descriptive material happens to pick out the same individual in every world. This can be done pending your view on the necessity of numbers, for example, using a description like "the successor of 2," which rigidly picks out the number 3, or by using a technical device like a modal actualizer, so that "the actual, current president of the US" picks out Trump in all worlds.

For the most part, descriptions made use of in natural languages are not rigid designators. But this is a contingent, and so interesting, fact about language. In constructing an artificial language, there is no problem with constructing rigid descriptions.

Nope.

Thanks – I've actually read that paper, believe it or not (I used to be interested in the semantics of names).

I'm sympathetic to the view that names do not exhibit this distinction, as Kripke predicts, due to their being rigid designators. The effects described have to do with independent mechanisms, though articulating exactly what they are is somewhat difficult. I doubt they have anything to do with names specifically.

So, when we talk about possible worlds, and specifically make stipulations about counterfactuals, then we are restricted to the domain of the actual world? Does that make sense? — Wallows

Not really. Are you talking about the domain of individuals?

What do you mean? — Wallows

In a standard quantified modal logic, there is a domain of individuals, and a set of possible worlds. Each world does not have 'its own' domain of individuals associated with it.

I believe the point I'm trying to make is the following and bears some semblance to the Barcan Formula in restricting the domain of truth-aptness to the actual world: — Wallows

The Barcan formula doesn't 'restrict the domain of truth-aptness,' whatever that's supposed to mean. It is just a formula, valid on an ordinary modal logic, and its validity follows from the way quantifiers and modal operators are ordinarily interpreted.

The issue you're talking about is that the Barcan formula's validity makes it impossible that worlds accessible from a world have 'larger' domains than the world from which they're accessed: in other words, domains don't 'grow' across accessibility relations. This is fine, however, not because of commitments to modal actualism, but because to think that distinct worlds are associated with distinct domains in the first place is a mistake. One can make a logic this way, but it is probably a bad idea. There is just one domain of individuals, and it is not anchored to worlds to begin with.

The validity of the Barcan formulae follows independently from ordinary, independently plausible semantics for the universal quantifier and the box. If one objects to it, one had better have a pretty good reason, and I'm not aware of one.

I suspect that resistance to it is due to the confusion that distinct worlds 'have' distinct domains of individuals associated with them, over which quantifiers operate. You can make your logics this way, but it's probably a bad idea. Many bad ideas in logic come from philosophers having qualms independent of the logic, and trying to force their prejudices back into the logic, with bad results. Presumably, in this case it has something to do with the idea that the domain of quantification represents what 'exists,' which is not right.

This depends on whether you are an actualist or possibilist for QML. — Wallows

No it doesn't. The modal logic is a formal device, indifferent to metaphysical interpretations of modality.

Again, I am professing an actualist interpretation of QML. If you assume my position then Counterfactuals can only be truth apt relative to our world. This is an assumption that I understand applies to both actualist and possibilist interpretations. — Wallows

There is no modal logic that in principle only allows the evaluation of a formula for truth relative to the actual world (you could create a vacuous frame with only one possible world, but this would be a pointless exercise, and says something only about the frame, not the logic). Indeed the entire point and expressive power of the logic is that it allows evaluation relative to multiple worlds. If you remove this, then you have a vacuous modal logic, i.e. one that only has the expressive power of a non-modal logic.

So, bear with my confusion! If we are to quantify over possible worlds then, we can only "measure" (quantify) counterfactuals by an accessibility relation to our own world. Therefore how can we assert something as necessarily true in all possible world's if quantification of modal relations (counterfactuals) is/are restricted to only our world? — Wallows

This paragraph just doesn't make sense.

What do you mean by "measure" or "quantify" counterfactuals?

There is no such thing as "an accessibility relation to our own world." Accessibility relations hold among a set of worlds – it doesn't matter which one is actual, and the standard modal logic does not even mark an actual world.

Modal logic's semantics determines the truth of a formula relative to a model, world and variable assignment – this also makes no mention of the "actual world." If you want to include a special, designated actual world to the model, you can do this, but it's just not needed for the semantics. The whole point of the modal logic is that any arbitrary formula can be evaluated fro truth or falsity relative to any world. And once you have a semantics for counterfactuals, you can plug this into your modal logic.

So far as I know, Quine isn't taken seriously on this matter.

Formally, there is no problem with it. I have never seen a philosophical criticism that was compelling either.

For a long time I thought that there was no convincing evidence one way or the other on this issue. The arguments of classical idealists are fallacious, but the materialist responses are very poor, and typically misunderstand the position or raise laughable objections against it. So I thought they were just two interesting speculative hypotheses in logical space.

I believe, however, that there may be some reason to favor the anti-idealist position, that I've recently come across. The argument is a little hard to articulate, and doesn't so much show a consideration against idealism as that it forces idealism to slide into panpsychism of some sort. But then again, I haven't thought much about the plausibility of panpsychism, which does not strike me as a priori absurd.

I really don't think intellectuals should bother engaging the public.

You mean, that all formulae are evaluated with respect to the actual world? — Wallows

No.

I'm not following. What does this have to do with the Barcan formulas?

In your standard modal semantics, all formulae are evaluated with respect to a possible world. This will include conditional or counterfactual formulae, however you translate or interpret them. Actualism about modality isn't a position affecting the modal logic per se. It's a metaphysical position, so when you're committing to using a modal logic, it becomes an interpretation of the metaphysical commitments of that logic.

I gather that you and Andrew have history. I'm not interested in playing. Yet. — Banno

Not that I remember or am invoking.

It may be just that I have been exposed to NN too much (people return to it often, because analytic philosophy is light on 'classics').

Do you think that Kripke does it well? I ask because andrewk's insistence that these are matters of taste is false – and I doubt this can be shown to him via the text on its own. Once you get to brass tacks, these things can be shown in more interesting ways.

I have also seen people try to work through NN over and over, and the same mistakes tend to be made, and explanation of them doesn't seem to help dispel them.

I don't really agree, but it doesn't matter. I think the intuitive glosses on these arguments just lead to interminable confusion. The 'telescope' theory of possible worlds needs to be shown to be undesirable by showing how it would have to be formalized, e.g. by Lewis' unwieldy and unattractive logic of counterparts, as opposed to the elegant Kripke-frames, where the domain of individuals is simply separate from the worlds of evaluation, which captures the phenomena he talks about wonderfully. The notion of a rigid designator is in addition just confusing outside of modal logic, because it's only there that the sense of 'in every world' receives any application: what's meant is in any world of evaluation, which is not a lay concept.

That article isn't addressing descriptivism about names. It's addressing the Russellian account of definite descriptions.

The translation you provide of the sentence isn't one available to the Russellian, though, so your defense here won't work. I can explain why if you want, but I just wanted to flag that this is a separate issue that NN doesn't deal with.

Do you know what the modal argument is? Can you restate it for me in your own words?

Have you read NN?

Not no one, but many of the objections are clearly confused, in a way that it would be unproductive to respond to. The notion of rigid designation, and how the same individual can be referred to across possible worlds, and how this accounts for the modal constructions Kripke is talking about, doesn't need all this explaining if you know how the modal logic works. Then one can focus on the actual claims Kripke is making.

Kripke invented the notion of accessibility relations in modal semantics.

I think reading NN without knowing about modal logic is pointless, as evidenced by this thread.

Myself, I think Russell's theory of definite descriptions is basically right. — Pierre-Normand

Russell's theory is probably not right. It makes a number of wrong predictions as to the behavior of definite descriptions in embedded environments.

https://www.readcube.com/articles/10.1007%2Fs10988-010-9072-3?author_access_token=SVx2QIwFk3kTTo8IyEVDRve4RwlQNchNByi7wbcMAY7iNlNgpGRzM_WD4_srx4OSluaaYmnLCu53v9bvVDa92yUqe-uN_ec2lwOPjxmkaterOX7qM5JgxBKBMjrqfPx6CudiP6v1X4Hp3jXoWtKFow==

I feel that my approach is the most natural in the world. — andrewk

That's not really relevant. There's a body of data w.r.t. how counterfactuals behave, and a theory to capture them. What you feel about the naturalness of anything doesn't matter.

One has to be careful how one sets up counterfactuals, because they usually end up being nonsense, no matter what metaphysics or language philosophy one favours. — andrewk

This is really not a good sign. Counterfactuals are ordinary tools of reasoning, and in many cases their meanings, and even truth conditions, aren't difficult to figure out. I am suspicious of error-theoretic or revisionary accounts of them, as I think Kripke is right to be in exploiting modal intuitions.

The idea that when we suppose something were some other way, we are not really doing that but positing some 'counterpart' to it, is otiose and makes understanding the semantics of referential expressions difficult for no payoff.

Syntactically, the subject is 'it.'

Semantically, there is no subject.

The subject is not the rain, because 'the rain is raining' makes no sense. Likewise for pretty much anything you put in place of 'it.'

Notice also that the question 'is it raining?' makes sense, but the question 'what is raining?' does not.

In languages, unlike English, where an overt syntactic subject is not obligatory, you often cannot put a subject before meteorological verbs like 'rain.'

If we're just saying that in counterfactual (or "possible worlds") talk, we can refer to things so that they're "the same x" as they are in the actual world, barring counterfactual modifications we make to them, and to some extent that's necessary to make sense of counterfactual talk at all, that shouldn't take a whole book/series of lectures to note. — Terrapin Station

It shouldn't, no. But David Lewis remained puzzled, I think, to the day he died.

I'm not sure in what sense the examples I gave are 'improper.' I'd rather say that a definite description has a certain semantic function, which in some environments yields a single referent, and in others doesn't. A name, perhaps, yields a single referent in a wider variety of contexts, though names also don't always behave this way either.

But not the other way around, yes? — Posty McPostface

Right, an object (that isn't a word) doesn't designate anything, in Kripke's terminology.

SO if "Neil Armstrong" means "The man who first walked on the moon", and yet it is true that some other person, not Armstrong, might have accomplished that task in his stead, then...

Are we to conclude that the man who was first to walk on the moon, might not have been the first to walk on the moon? Or does this give some undue importance to the actual world? So the statement "Armstrong might not have been the first man to walk on the moon" really means that the man who, in the actual world, was first to walk on the moon, might not, in some other world, have been first to walk on the moon... — Banno

The significance of the claim, as I read it, is that the sentence 'Neil Armstrong might not have been the first man to walk on the moon' is true, and has no intuitively false reading. But if Neil Armstrong has the same semantic value as 'the first man to walk on the moon,' then there should be a false reading of that sentence (though there may be a true one as well, which you highlight here). In other words, the definite description account overgenerates readings here, and there is no way to read the sentence as necessarily false. This is evidence that the name refers to that man, and not to whoever was the first to do what he did.

A definite description is (supposedly) a predication that picks out an individual by what it true of them. "The first man to walk on the moon" picks out Armstrong.

A rigid designator (supposedly) picks out the very same individual regardless of what is true of them. "Neil Armstrong might not have been the first man to walk on the moon." — Banno

A couple things here:

-Definite descriptions and rigid designators aren't mutually exclusive. Most definite descriptions aren't rigid designators, but some, perhaps, are (I think Kripke's example is 'the even prime,' which rigidly designates 2).

-"The first man to walk on the moon" picks out not Armstrong, but whoever happens to have been the first man to walk on the moon. In actuality that happens to be Armstrong, so in the modal logic, relative to the actual world, it picks out Armstrong. "Armstrong," we might say, then just picks out Armstrong simpliciter, and its semantics has nothing to do with walking on the moon.

I really don't think these things can be elucidated without understanding the modal logic, so maybe we differ here. I'm almost inclined to think that reading NN is pointless without a first course in modal logic.

I will let Banno clarify my confusion. I've always held that objects are rigid designators to the act of baptism of a name. — Posty McPostface

Nope. "Rigid designator" applies to terms, or words. The definition is on p. 48. You can say that a name rigidly designates an object.

I'm still playing catch up. But, if you want to hear my dribble then a name attains meaning when it has a rigid designator that instantiates a concepts or a web of beliefs about it or otherwise known as definite descriptions in the world. My only concern is how do definite descriptions obtain wrt. to rigid designators. — Posty McPostface

A terminological thing here: a name doesn't have a rigid designator according to Kripke, it is a rigid designator. A rigid designator is a kind of term or word. A name has a referent.

My bolding.

Consider pp. 31-33, where Kripke points to a difference between a name having a meaning, and a name singling out its referent. "Moses does not exist". If the sentence is true, and Moses does not exist, then "Moses" means, say "the man who led the Israelites out of Egypt"; and refers to nothing, since there is no such man.

So there seems to be a difference between the meaning of a name and what it refers to. — Banno

I don't think there's any reason to think the name refers to nothing if there is no such man. That is, Moses need not exist for us to refer to him – we refer to all sorts of things that don't exist. Prima facie the opposite opinion isn't plausible, so I wouldn't adopt it without some good ulterior reason. And so I think this problem, or distinction, or whatever, doesn't get very far.

A definite description picks out one and only one individual. Agreed? — Banno

Sometimes. Definite descriptions also have covarying readings with no single referent:

"Every author who writes a story shows the story to an editor."

Here "the story" does not refer to a single story.

Some definite descriptions do not even refer to any existing individual:

"If I had written a story, I would have shown the story to an editor."

I'll do it.

But you said the argument had nothing to do with interest, and the argument in the first post very explicitly does. In order to address the issue, you need to be clear about what you're actually claiming.

I think both arguments are very bad, but the response will change depending on which is addressed.

Which posts are you referring to?

Would you rather people address the argument in this post:
https://thephilosophyforum.com/discussion/comment/220479

Than the one in the OP (they are not the same)?

Here's a bad way to argue:

We're trying to decide between two positions, A and B.

You present an argument that A is true, because of fact X.

Your interlocutor points out that nothing about the truth of X entails A, and so this is a bad argument: the conclusion has nothing to do with the premises.

You respond by saying, well of course it's still possible that B given X, if you take for granted that B!

This is not an effective argumentation strategy.

The fact is that whether or not mathematical objects are interesting to creatures that study or make use of them has nothing to do prima facie with whether there are not such objects. This is, as it stands, a terrible argument. If you want to try to make it better by trying to provide some bridge principles (why should we think that the existence of mathematical objects is contingent on, or interestingly tracked by, the interests of creatures? We're not inclined to think such a thing for any non-human creatures: things are still countable by number, even though there are no creatures who can count!), that's fine, but you can't simply double down.

In other words, we are looking for some reason to accept a premise like:

"A mathematical object exists only if it is interesting to some creature."

This is on its face an absurd claim. Can you give us a reason to believe it?

It's only a 'conflation' if one assumes from the outset the Platonic position on mathematical objects. — StreetlightX

No, not really. If you begin with the neutral position, it is the one making the argument that begs the question.

It doesn't matter if you're a Platonist or not; the argument is simply bad.

The vast majority of it is simply useless, and of no interest to anyone whatsoever. — StreetlightX

So?

The argument straightforwardly conflates mathematical objects with mathematical practices developed using, or developed to describe, those objects. No one doubts that the mathematical practices of organisms are fluid, but that's not relevant to the Platonist's claim.

SO the argument would be that he understands the concept, but is unable to use the word. — Banno

No, he understands the word, without impediment. Yet his use of it is restricted.

Hence, your original claim, that to understand a word is to be able to use it, cannot be right.

No, but being able to say it is a huge part of it.

Lacking the ability to say it hugely hampers your ability to use it; it does not hamper your ability to understand it. Hence, understanding and ability to use cannot be the same.