I don't it's a case of ambiguity. You just don't have enough information to know what's being asked. You'd have to go back and get the request clarified, right? — frank

Because it's ambiguous. I'm struggling here to guess how you understand that word.

But communication failure is not the main point here; it's that you have the option to treat shared abstract properties as singletons, but you do not have that option with the objects instantiating them.

That sounds very promising.

This is definitely a tangent, but I was just thinking of a puzzle that can arise with properties -- it's close to the distinction between in sensu diviso and in sensu composito, or maybe it's just the order of quantifiers, I'm not sure really. Suppose you have a bunch of marbles, some red and some blue, and you are asked to "list the colors of these marbles." There are two good answers: {red, blue} and {red, blue, red, red, blue, red,...} What is wanted? "Of each color, that it is represented"? Or "Of each marble, its color"?

I thought of this because if instead you were told to sort the marbles by color, there's no ambiguity -- well, not this particular ambiguity. Someone might distinguish the reds and blues more finely, but then we'd be back at the first ambiguity, which is really along a different axis, right?

I wouldn't even throw this little puzzle out there if it weren't for what Kimhi says about propositions versus actual occurrences. The options you get dealing with marbles are different from the options you get dealing with the colors of marbles.

I think abstract objects are products of analysis. — frank

Yes, but I would suggest that we shouldn't take the word "analysis" there to indicate a practice that stands outside the everyday use of language, as if this is only something done by a linguist examining a corpus or a philosopher examining whatever she does, arguments, intuitions and whatnot.

Instead, this kind of analysis is engaged in every day by ordinary speakers and listeners; making distinctions like what-you-said vs how-you-said-it are strategies we all use, sometimes to understand each other and sometimes for other reasons. Doing this kind of thing is as much part of being a member of a linguistic community as knowing the word for "window" or the polite use of pronouns.

I hope I didn't suggest that there's only one type of abstract object. Quite the contrary. Mathematics alone provides a considerable menagerie.

For purposes of this thread, the ones that would matter would be, at least, content and force.

There is a suggestion, speaking roughly and quite broadly, that a system of logic intended to deal with our utterances only as content, without force, is somehow mistaken. That may be so, but it's no argument to say that our utterances also have force if the whole point of the enterprise is to set force aside without denying it.

It might be closer to the argument given to say that Frege, in particular, does not set aside force (even if other and later logicians do) but that he brings it in in a way that is somehow at odds with the unity of force and content in our utterances. That might be a claim that it is a fool's errand to distinguish force and content (somewhat as Quine argued the impossibility of separating the analytic and synthetic 'components' of a sentence), or it might be a claim that Frege has distinguished them incorrectly, or something else, I don't know.

I've not spent as much time as I might have thinking about Kimhi's argument, but the claim of conflation suggests that there is a point you can make about content, the proposition, and a different point you can make about actual occurrences, in which that content features, but Frege, I think it is claimed, forgets what he's about and tries to make a single point about both, or tries to make a point about one that can only be made about the other, and somehow tricks himself into thinking he has not mixed up the two.

That's the terrain of the argument I'm unable quite to present, I think.

That's what a proposition is supposed to be: that thing we can agree or disagree on.

If you start with a strongly materialistic bias, you're likely to lean toward behaviorism, which says that we never really agree on anything. — frank

I can say we agree, and I can say what we agree on, without attributing to "what we agree on" independent existence, but instead treating it hylomorphically as an abstract object that is immanent within our agreement. "Our agreement" is another such abstraction. Does it exist independently of our agreeing?

These two objects have the same mass.

These two cartons have the same number of eggs.

These two sentences mean the same thing.

I take this passage to be central to what Kimhi wants to say — J

For this thread, it is absolutely central, this claim of conflation.

You can consider a physical object as having properties such as mass, velocity relative to a frame of reference, and so on. The mass of an object, for instance, can be treated as an abstract object, but hylomorphism comes naturally here, and almost no one is tempted to say that the mass of the object has some existence separate from it. Nor does its velocity or any other property.

Now consider things people say to each other. You might very well find reason to distinguish what someone says from how they say it, or what someone says from the importance they attach to it, and so on. You might distinguish what someone says from the specific words they used to say it, including which language they used, so that people speaking English and German can say "the same thing".

"What he said" looks a lot like an abstract object, along the lines of mass, but for some reason many people, perhaps including Frege, have been tempted to treat "what he said" as having an existence independent of the words he used or the sounds he made.

For the issue Kimhi wants to raise, the issue would be whether you are conflating two different objects (or kinds of objects) that have independent existence, or whether Geach and Frege have conflated two different 'descriptions', I suppose we could say, two different 'qua ... ' formulations.

Does it matter what's being conflated?

I think it might for Kimhi's argument because one way of buttressing the idea that propositions have independent existence is to align them with the mental, rather than the physical. There's more, of course, but here, I think clearly, the question is in what sense "what he said" is a thought, while the actual words spoken were merely a physical "expression" or even representation of that thought.

If we take a more hylomorphic view, there may still be an argument, but it won't be this one.

I still don't see that this follows. — J

This is a good response. Heidegger relies on exactly this hermeneutic circle in everything he writes. It's prima facie a reasonable description of learning.

"make-believe" is a lovely phrase. I should have used it.

I agree that a picture is not capable of depicting that it is true. However, I question the practical import of that to some extent. — wonderer1

Maybe it's only important to philosophers and other such model builders.

On the other hand, I think people often tend to treat memories as a class of "pictures", broadly, that vouch for their own truth by being the kind of picture they are. And of course they're wrong.

It's an interesting question though. What was Wittgenstein trying to block by making this point? I should go back to TLP and look, but one thing that comes to mind is this: if you want to know if a picture presents the truth, you need another picture that says that. You can see where this is headed.

It seems to be a denial that there is any self-evident truth -- which would be handy for capping off the regress -- but that's not quite right; I think the claim would be that there is no substantive, we might say, self-evident truth. It's in the TLP (according to my lazy history of logic) that we get the presentation of tautology as a true statement that says nothing. And if it says nothing, evidently not a picture. So the truths of logic are something else entirely, and it is only there, among these whatever-they-ares, that we get self-evident truth.

Isn't it a category error to challenge the fiction author regarding warrant? — Leontiskos

CHAPTER I.

YOU don't know about me without you have read a book by the name of The Adventures of Tom Sawyer; but that ain't no matter. That book was made by Mr. Mark Twain, and he told the truth, mainly. There was things which he stretched, but mainly he told the truth.

My point is that first and foremost the fiction writer *pretends* to have such warrant. In early prose fiction this is almost universal (in English anyway).

Nowadays, we're used to how fiction works and it's dramatically less common to go through this little dance.

And the point of all this is to clarify how we usually offer and receive declarative utterances, so that we know what's been stripped away when we consider the bare words, as we might when playing at logic.

I *think* this is in the neighborhood of Kimhi. I'm under the impression he wants to restore the thinker to the thought, or maybe it's thinking as what links what is thought to what is. I haven't put a lot of time into figuring out what he's after, obviously.

It's not novel to say that something is stripped away when we engage in logical analysis. It's more or less the point. The question is whether what you have left, that you'll submit to logical analysis, is what you think it is, and whether the pieces fit when you try to reassemble the living use of language.

You can have beliefs and intuitions about them all you like, you just can't smell, see, taste, touch them (except figuratively). — fdrake

That's close to my answer.

The obvious candidate for what's missing is belief, but I don't think that's quite it.

(I'm only indulging here because I keep seeing echoes of the actual topic...)

The main pretense in story telling, I claim, is about the story teller. They pretend to know a story they're actually making up (or that someone else made up). In early prose fiction, there's often a bit of BS at the beginning about how the writer stumbled on these letters, how he came to have this diary, or (nearby in poetry but right time period) some mad old man stopped me on my way to attend a wedding.

I think more than belief is at stake, because we judge beliefs on how they were arrived at. The challenge of someone who doesn't believe a story you're telling, even a true or at least honest one, is "How do you know that's what happened?" It's not just a question of whether the teller believes the tale, but whether their life history entitles them to it, gives them warrant to tell it. Hence the pretend warrant fiction writers sometimes display.

So yes, somewhere back in the chain of how I come to be telling this story, to be in a position to tell this story, there must be witness or even participation. I was there and I saw it, or I had it from a guy who was there. The storyteller pretends to be such a person.

This is, perhaps, a more colorful version of the Parmenides stuff.

One consequence of such a view might be that it's not really the tale we believe but the teller. We do not adopt a propositional attitude of "belief" toward the story, except perhaps as a consequence of adopting a social attitude of "trust" toward the storyteller.

--- back to work ---

pretending and playing is very different from the logical thinking that Frege and Russell prefer — Leontiskos

Pretending, as your examples demonstrate, is complicated, but I think it's actually very important to logic because of hypothetical reasoning (not to mention counterfactuals). I think it's very difficult to give an account of what happens when we entertain an hypothesis, but it looks a bit like pretending. When doing philosophy or mathematics, we say things like "Suppose I have an urn with 100 marbles in it..." and we could very nearly (?) say "Pretend I have an urn... " "Pretend you've drawn a red marble", and so on.

--- More to come later, but I really have to work for a few hours.

something like examining a corpse — Leontiskos

Very plausible. Taking down the words someone spoke leaves an awful lot behind. As musical notation is a somewhat limited representation of someone playing an instrument.

Coming back to fiction, it's probably a blind alley to think there's something added to the words in place of assertion; the pretense is that you are removing something and pretending you haven't. And the audience agrees to pretend you haven't -- to a degree, or in some particular way. ("Willing suspension of disbelief" is probably much too strong, if not just wrong, because people watch horror movies.)

A better form for my question would be, what have you removed? What's missing, that everyone kinda pretends isn't, when you tell a (fictional) story? Does it overlap with what's left out when you only have a record of the words spoken, the bare, lifeless sentences?

Are you thinking of a sentence or a proposition? — frank

Sentences or maybe utterances, depending on how you'd like to slice it. It's not obvious to me you can utter a sentence without uttering it in a particular way, which would include something like force.

I would love not to talk about propositions at all, so I'll leave that to you.

And one last point -- sorry for the multiple posts -- the whole point of my view of fiction is that it is parasitic on candid account giving or reporting. If we did not already have such a practice of reporting on real events that happened to real people in real places, and so on, we could not pretend to report on events we've made up (and maybe people and places as well).

Another way to look at it: if you're not sure whether assertion is something we add on (rather than being built in), does showing that we can add something else instead of assertion show that assertion is something we add?

if telling a non-fiction story is a form of assertion, and telling a fiction story is not really assertion, then what is it? — Leontiskos

Yeah that was the idea. Is assertion something added on to the words? If you can add on assertion, are there other things you could add on?

It seems clear that Kimhi accepts a logical subject in the way that (early?) Wittgenstein does not, and can thus introduce consciousness. — Leontiskos

Shaky ground for me, but I don't think that's right. The alternative title for the Tractatus is "The World As I Found It". "The limits of my language are the limits of my world." There's that business with the eye, and the little picture showing how the eye is its own horizon, never included in what it can see. The issue of solipsism is addressed directly. There's a pretty strong sense of "I" at least in parts of the Tractatus, and it would probably be fair to call it "logical". -- Honestly not an aspect of the book I ever gave much thought to though, so I might be off base here.

Fiction is a minefield for discussions like this, and I don't want to derail the thread, if that's even possible, but I'll make one point.

My view is that in a work of fiction the author pretends to be telling a story, as she might tell a story about something that really happened. We pretend to believe she's telling a story. An author pretends to be telling the truth. (I think it's a pretty sophisticated thing, and it's easy to be culture-bound and miss how unusual it is.)

A relevant (for this thread) question might be: what exactly is an author pretending to do that he isn't? Can we say, there's the sentences you speak and the order you speak them in, on the one hand, and something else that makes your speaking "reporting a sequence of events" or "(merely) telling a (fictional) story" on the other?

My memory of the Tractatus is that Wittgenstein also says that a picture is a fact, it's part of the world, and so to say this is a picture of that is to say that between this fact and this other fact there is a special picturing relation. And he wants to figure out what it means to say two facts are so related and how it is possible for them to be. (I'm thinking of this in part because Kimhi ends up talking about consciousness, right? So you might take consciousness as the locus of this relation, or even as constituted by it.)

The more natural move for later Wittgenstein is to say that sometimes we see something as a picture of something else, sometimes we don't, and that it is a far more flexible business than it might seem in the Tractatus. The duck-rabbit shows flexibility in what something is a picture of; the possibilities for what counts, or what someone might count, as a picture of a given thing are too numerous to contemplate. (Think of how often only a parent can understand the first indistinct words of their own child. Now consider the range of possible pictures of a dog, from that toddler's wobbly shapes to a cubist painting or an abstract sculpture, and "everything in between", photos, icons, words, pantomime, on and on. Clouds!)

Is there then something between assertion and non-assertion? — Leontiskos

Almost everything I've posted in this thread.

There are a couple places where I was moved to think, but nothing much came of it.

Most of my posts have been pretty lazy, stuff I can post on auto-pilot. Sometimes I do this just in case I happen to know something someone else would find useful. If you asked me if I believe any of it, I'm not sure what I would say.

I like the stuff about the screwdriver. And I'm right about triangulation. Everything else was chit chat. Philosophical gossip.

I was a bit puzzled by this so I asked ChatGPT o1-preview the following question — Pierre-Normand

Just so you know, I'm not going to read that.

just tell me whether you understand the word on the paper or not — J

Are you puzzling over the context principle, is that it? Are you asking if Frege is literally saying a word isolated like this, not part of a sentence, is meaningless?

Don't worry about it. Frege is not that dumb. I believe Dummett's formula ends up being: "The meaning of a word is the contribution it makes to the truth conditions of the sentences in which it is used."

You can still get some straightforward compositional semantics out of that. But the approach Dummett is championing has to put sentences first: sentences have truth conditions, and words don't, so the sentence is where we start.

As for your "Berlin" example, you don't understand it. It could be a lot of things. Name of a city, name of a band, name of a book, an adjective describing a strain of flu. Without the context of a sentence -- and honestly much more context than that -- you can't know what referent "Berlin" is intended to pick out if any. You might know a lot of options, but even for a single word there are more possibilities than you can imagine.

is it possible to see that something is true before going on to assert it? — Leontiskos

There's a couple ways to read this, but at any rate, a couple obvious options:

1. Under the usual understanding of assertion -- just to get this out of the way -- it's perfectly ordinary for people to make claims the truth of which they do not know. They may indeed be aiming at truth, but when you loose the arrow, while you may feel some confidence of the result, you cannot know whether you've hit the target.

2. From the other side, once you "grasp" the truth of a situation, have you any choice but to affirm it? This would seem to be somewhat closer to the sense of assertion intended. In other words, Moore's paradox is a simple impossibility: to see the truth of a situation or a proposition is to believe it.

But I want to make a bit of a different point. On my (admittedly limited) understanding of the Tractatus, one thing a picture is entirely incapable of depicting is that it is true. A picture can show how things might be, and things may indeed be that way, but the picture cannot include itself in its depiction and vouch for its own accuracy.

Just so, my belief that a picture is accurate does not count as evidence that it is.

We have talked some -- whether we should have or not, I'm not sure --- about whether there's some sense in which propositions are self-asserting. In these terms, whether a picture at least inherently claims that things stand as it shows, even if it cannot itself substantiate that claim.

On the one hand, this seems a bit foolish. Pictures can show how things aren't, so why would they have to be claiming that things do so stand, how would they, and why would anyone care if they did: if all pictures claim to be true, you can ignore their claims. If, per impossible, a picture could show that it was the truth, that would be something to pay attention to. They can't, and claims are cheap.

On the other hand, in the wake of the Tractatus and Carnap and the rest, we got possible-world semantics; so you could plausibly say that a picture showing how things could be is a picture showing how things are in some possible world, this one or another.

The feeling of "claiming" is gone, but was probably mistaken anyway. In exchange, we get a version of "truth" attached to every proposition, every picture. Under such a framework, this is just how all propositions work, they say how things are somewhere, if not here. Wittgenstein's point could be adjusted: a picture does need to tell you it's true somewhere -- it is -- but it can't tell you if it's true here or somewhere else.

I don't want to get into this too much, but yes, in trying to keep conscious, attentive decoding out of it, I do make understanding sound too passive. I think the evidence is that understanding is pretty darn active (we predict the ends of sentences before we hear them, guess what the other person is going to say next, back-channel to guide their speech, and so on). It might still make sense to say that we don't choose to understand other people's speech this way, it's just what we do.

I was very impressed by Austin's claim that it normally doesn't make sense to say that I sat in the chair "voluntarily" or that I sat in the chair "involuntarily" -- as doctrinaire views on free will would require -- but each fits special circumstances which call for such an adverb. Just so, I'm resistant to analysis that treats all of our declarative utterances as deserving an "I judge that ..." or "I believe that ..." in front of them. Sometimes we judge, sometimes we go out of our way to mark what we're saying as our personal belief, and sometimes, probably mostly, we just talk.

I still don't know what this thread is about, but I'm pretty sure it starts in a place pretty far from me and goes in the opposite direction.

Here's a fun read on Carroll and inference --- also handy because it mentions a lot of the best-known work, including a few I've missed. (You could probably get something similar out of SEP, but I'm allergic to SEP.)

the way in which Frege forbids predicating existence — J

Consider this: if you can predicate existence, can you also predicate non-existence? (Or, what is the same thing, negate a predication of existence.) And *what* would you predicate non-existence of?

I'm tempted to warn you off this whole thing -- which gets rehashed regularly -- but there is a sense in which Frege's system automatically narrows the the field of true statements to statements about real things, and that does seem relevant to Kimhi's whole invocation of Parmenides. Somehow. Not waters I like to swim in.

Do you know Russell?

The thing about "The grass in my backyard" as a denotative phrase is that it has that "the" in it, which Russell gives a famous analysis of, claiming it includes a sort of hidden existential quantification.

Frege is not giving a simplification or a model — Leontiskos

That may be true, but it's been a serious point of contention in the post-Frege discussion of language.

And here I'll mention, for the nth time on TPF, the comparatively little-known view of Tarski's star student, Richard Montague, that there is no distinction between formal and natural languages, because natural languages are "formal" in the intended sense, and that linguistics is a branch of mathematics. Montague presents his analysis of the logical constants as the semantics of natural language. Certainly a maximalist take on the formal view of language.

And I guess we ought to leave this more general discussion of the underlying issues there.

Broadly -- I think everyone knows this, but here we are -- the two principal strands of thought about language are: language as symbol system (which facilitates thought); language as communications system. Frege is generally treated as part of the former camp, and early Wittgenstein, and the latter camp includes later Wittgenstein, Grice, et al. (David Lewis makes an heroic attempt to marry them in Convention, and admits that he cannot.) For what it's worth, I'm in the latter camp, but see the sort of analysis the former produces as a useful strategy in some cases.

But language is easy (!) compared to logic. It appears to me that research overwhelmingly supports the communication-first view, but there is no simple path from there to a similarly robust take on logic, not that I've found anyway. That's uncomfortable for me, but oh well.

And Kimhi seems to me mostly to be talking about a pretend world, or at least mistaking the simplifications (that is, fictions) we employ, like "grasping the truth of a proposition", for reality. (And note that mathematics is such a pretend world where logic runs like a champ without any of this psychological baggage.)

The puzzle is explicit in Frege's requirement that only true sentences can be asserted, a requirement that is incomprehensible to, and thus not even understood by Russell and Wittgenstein. If only true sentences can be asserted, then what exactly is the difference between calling a sentence true and asserting it? Frege has an uncommonly objective notion of truth (and also assertion) (at least as far as contemporary logic is concerned). — Leontiskos

Indeed it is so incomprehensible that I didn't even remember this was Frege's view.

Which suggests to me that "assertion" is really not a word we should be using at all here, given its modern meaning.

I may have missed it, but I suppose this applies to "judgment" as well, that you cannot judge as true what is false.

All of which points toward that favorite (never defined) word, "grasping". So it's about grasping the meaning of a proposition, grasping its truth, the difference between those, and so on.

and the class of things which are thus and so is not empty — Leontiskos

Eek. Not only is this part redundant but it requires classes to be objects, which pill, though bitter, even Quine swallowed for the sake of mathematics. But we don't have to go there just for this.

(It's also Quine who pointed out that names for individuals are eliminable. You just make a predicate like "Socratizes" that is satisfied by a single individual. That might not strike you as either intuitive or felicitous, but it's a typical math move, to subsume a particular problem into a more general one.)

a kind of thinking together — Leontiskos

It's ironic you say this.

My deep dissatisfaction with everything I've read of Kimhi was precisely the emphasis on assertion, judgment (a word I've never had any use for because of its libertarian aura), and this "I" of logic.

I've been thinking a lot the last few days about the "we" of logic, but so far it's not in good enough shape for the thread I promised.

Anyway, this "I" stuff is why I'm not bothering about Kimhi anymore.

I don't even want to talk about Kimhi, so new thread it is.

A logic which presupposes judgment is something fundamentally different from a logic that does not. Frege and Kimhi both maintain that logic presupposes judgment. — Leontiskos

Well, that's the thing. You're talking about Frege says about his system. And I'll grant you, the first version of the system we all know now as "classical logic" included some notation that Frege thought important, which it turns out had so little to do with how the system was actually used that it disappeared without a trace, leaving the system essentially unchanged. You're right that Frege might not see it that way, but the facts on the ground tell a different story.

What's ironic about this story, is that it's as if we're talking about Frege's "interpretation" of the predicate calculus, considered as a system of symbol manipulation, which in a sense is precisely what's at issue. That means each side can retreat to their preferred view and consider the other misguided. Not a great result. (And of course a third party might see the dispute as "merely verbal".)

I'm going to propose what I hope is an alternative view in a separate post, so as to please no one.

Sorry, I didn't understand a word of that.

We can understand “The grass is green” without knowing whether or not it is true, and whether we should affirm or deny it. — J


It is that last part I am trying to focus on.. As clearly Frege believes it and Kimhi agrees. — schopenhauer1

I think the argument has been that Frege believes this must be so, and Kimhi claims it ain't necessarily so, but sometimes it is. I haven't wrapped my head around what is supposedly the main topic of this thread yet.

what is the criteria for truth, for Frege or otherwise — schopenhauer1

This phrase "criteria for truth" -- what could that possibly mean? How can anyone have one of those?

Frege simplifies what is not simple. — Leontiskos

Shrug. That's how simplification works. It's a model; all models are wrong.

Frege and Kimhi do not seem to be at odds on this point — Leontiskos

For instance, my little triangulation model is waaaaaay simplified.

Correctly understood as Wittgenstein’s point, Frege’s observation concerns actual occurrences of a proposition and amounts to the full context principle — Kimhi, Thinking and Being, 38-9

I always read the "language-game" analysis as an expansion of the context principle, so I have some sympathy with this view.

I do want to note the alternative approach, though, which is Grice's, and which I also have considerable sympathy with. Grice distinguishes sentence meaning from speaker's meaning, and defends the usual logical analysis of the meaning of a sentence as essentially correct, even if in a given context a speaker means something else by saying it.

An example I've used before: you're driving somewhere with a friend and ask, "Should we stop here to eat?" Your friend checks his phone and says, "The next town is like 70 miles." What he means by saying this is "yes", but that doesn't change the meaning of the sentence he uttered or of any of the words in it. --- Nor is "yes" logically implied by what he said; it is only implicated, and he might in fact be willing to wait.

I say all this because if you want to identify the meaning of a sentence with its use, as a move in a language-game -- what I think Kimhi might be pointing at with "actual occurrences" and so on -- you can get speaker's meaning right but skip entirely over sentence meaning, which in this case is a verifiable claim about geography.

It does seem like the principal subtext here is the picture theory of the Tractatus and its abandonment.

Russell is stultifying. — Leontiskos

Awww. :(

Sitting in the library reading "On Denoting" changed my life. It felt like coming home.

"There are a great many qualities one could attribute to the First Gentleman of Europe, but an interest in the law of identity is not among them."

Happy times.



Antinatalism is the poster boy for playing with Big Important Ideas not always leading to wisdom or insight. At least the minutia-mongerers among us aren't so foolish as to think there could be such a thing as an argument against life.

I think we can say this: a world with declarative sentences in it, or a world in which they can be produced, is a world that also includes assertion. A screwdriver is an element in a system of fastening: without screws of the appropriate material and materials to be fastened that screws can be driven into, there's no reason to have screwdrivers. To then take the screwdriver as having, shall we say, significance in itself, would clearly be mistaken.

What that gets us, I'm not sure. If you say, for instance, that assertion "aims at truth" (which, perhaps mistakenly, I suppose is the sort of thing Kimhi will want to say), then a declarative sentence must be the sort of thing that can be aimed at truth, whatever that means. One adjustment to this I would probably make is to say the goal of assertion is to aim someone else at truth -- at what you take for truth, anyway, so that's another adjustment. It's a triangulation: if you imagine yourself at vertex A, observing a truth at vertex B, then you speak to someone else at C to guide their gaze toward the (purported) truth at B.

There is something faintly Fregean about this, because of B. Frege's arguments for the "third realm" were often intersubjective: there is not "my pythagorean theorem" and "your pythagorean theorem" but "the pythagorean theorem"; if I claim that P is true, in order to agree or disagree you must be considering the very same P, else we talk past each other; and, finally, there was the telescope, where we can each in turn view the image on the mirror, rather than viewing the moon directly, but it is the same image we observe -- this to explain the difference between sense and reference, as I recall, and to insist that senses are not subjective.