I gave a clear illustration of what categorical non-existence would be like: Every modification of "A does not exist" is true. "A does not exist as an idea" is true. "A does not exist as a potential idea" is true. "A does not exist as a symbol representing something else" is true. And so on. — WISDOMfromPO-MO

This still just looks like the copula to me. "A is not an idea." "A is not a potential idea." "A is not a symbol representing something else."

There is weirdness here even Frege couldn't get around. Something that can be said to fall under or not fall under a concept is an object. What's a concept? Yuck. We have no choice sometimes but to talk about them as things, because grammar, but insofar as you talk about a concept this way, you're talking about it as an object, not as a concept. It doesn't really matter, so long as you get the knack of working with objects and concepts, and we all do.

So there is an "easy" answer to your question: Fregean concepts are predicated of objects but are not themselves objects and are not predicated of. They're never on the left-hand side of the copula, always on the right.

And the other easy answer is, everything that doesn't exist. I don't have a sister. The phrase "my sister" when spoken by me is a vacuous singular term. You can choose between saying all statements of the form "My sister is (not) ..." are false or not well-formed, as you like, but none of them will be true.

There is so much stuff that categorically doesn't exist, you couldn't begin to count it.

Again, a case could be made that in some way, shape, form, constitution, state, etc. the Empire State Building has a long existence--the beginning of which cannot be demarcated.
Somebody might say that the thing in the minds of business people, architects, etc. was the idea of the Empire State Building or the design of the Empire State Building, not the Empire State Building itself. At what point did that idea or design come into existence? I think that any attempt to answer that question is going to end up like the original question (at what point did the Empire State Building come into existence?). We get an infinite regression with no demarcation ever emerging, it seems. — WISDOMfromPO-MO

Does it bother you that people often report the exact moment when an idea occurred to them?

Yes. At least we can readily understand that feeling and understand what it would mean for it be true that people are staring at you. That is not generally the case with when it comes to purported experiences of God. You get obscurity, you get confusion, you get speculation, you get descriptions of feelings. But feelings aren't God. — Sapientia

Suppose I candidly describe the experience I am having right now as the feeling that people are staring at me. That I am having some feeling, you would consider reliable, maybe even incorrigible. But do I also know that it is the kind of feeling that in the past has been correlated with people staring at me? It would be an additional step to say, because I'm having the feeling, people must be staring at me, but is there something you would call interpretation at the previous step, of identifying it as that sort of feeling? Do I interpret my feeling to be the one I think it is, and describe it as, or is this something I reliably, if imperfectly, know?

I'm still trying to figure out what part of a person's candid report of their experience they are expected to justify.

Anecdotal evidence is evidence, and not proof, so it is not absolutely reliable. — Sapientia

Sorry, I was unclear. I was thinking of "reliable" in a slightly different sense. A person might conceivably be mistaken, say, about being happy, but it seems unlikely; we might decide to treat candid reports of emotional states as reliable, in the sense that people are seldom wrong about their own emotional state. I'm not talking, yet, about how we treat their reports as evidence, but about how they describe their experience when they have the intent to describe it truthfully.

That I had an experience a moment ago is not something that requires interpretation. It is self-evident. That it was an experience of this or that may require some interpretation. There are plenty of cases in which it does involve some degree of interpretation, and this is perhaps most evident when we get things wrong. We can be adamant that it was thus and such, when it was otherwise. Sometimes we realise our mistakes, other times we're oblivious. Justification is especially required if it's not a minor detail, but something hugely controversial.

It isn't necessary to reason backwards as you describe. What I describe is about reasoning forwards from accumulated experience. — Sapientia

Are you saying that an individual learns how to judge her own descriptions of her own experience in a way similar to how someone else might? Maybe inductively, something like, almost every time in the past I've thought I was looking at a refrigerator, it turned out I was. Maybe there can be other guides too: I am having that feeling that people are staring at me, but I have learned from my therapist that's probably not true. Is this the idea?

Btw, I once heard Hugh Kenner talk about Chuck Jones, and he said Jones's favorite author was Mark Twain. Jones, he said, seemed very nearly to have Twain memorized, could quote at length from many of his books, etc. Ever since then, I've thought of Bugs as having Twain's sardonic worldview.

This doesn't answer your questions, but I can't pass up the opportunity to post it:

My taste is for keeping open house for all sorts of conditions of entities, just so long as when they come in they help with the housework. Provided that I can see them work, and provided that they are not detected in illicit logical behaviour (within which I do not include a certain degree of indeterminacy, not even of numerical indeterminacy), I do not find them queer or mysterious at all…. To fangle a new ontological Marxism, they work therefore they exist, even though only some, perhaps those who come on the recommendation of some form of transcendental argument, may qualify for the specially favoured status of entia realissima. To exclude honest working entities seems to me like metaphysical snobbery, a reluctance to be seen in the company of any but the best objects. — Paul Grice

Almost definitely (b) with a few reservations (I could be wrong) and possibly (a). With regards to the latter, one cannot have an experience of God if, upon analysis, this makes no sense or implies a contradiction. And with regards to the former, how could one know that the experience is an experience of God and not an experience of something else? I'm not convinced that one could. One could of course be certain that it's the former, but that doesn't say much. I might be certain that my experience the other day was of ghosts, when it could in fact turn out to be just of a dim, candle lit, shadowy hallway, when I was tired, and in a heightened emotional state. Of course, I'd need to justify that it was of ghosts, but how?

Why wouldn't I take someone at their word when they give a description of their experience that doesn't contain anything controversial, like it being of God or ghosts or whatnot? That's being charitable, and it goes back to what I said in relation to anecdotal evidence. We know that people can and do have experiences which are profound or shocking or which they find remarkable in some way. It's quite natural and ordinary for someone to have such an experience or even multiple experiences of this kind in their lifetime. We also know that people can and do jump to the wrong conclusions after having certain experiences. I can relate both of these to my own experience. — Sapientia

There are (at least) two layers here:
(1) is there a reliable and and an unreliable part of a person's report of their own experiences?
(2) if (1) is true, is it only the unreliable part that is interpreted, and subject to standards of justification?

It stands to reason that if you believe part of a person's report can be rejected, then at least part of their report is unreliable. Perhaps you will hold that nothing in a person's report of their own experience is reliable, but perhaps you will hold (1), that there is a reliable part and an unreliable part. Then you would need to show how you are making that distinction.

It might seem that the distinction in (2) automatically matches up with the distinction in (1), but that is not so. It may be that all of the report involves interpretation, but the reliable part is interpreted in a way that meets our standards of justification.

Can you reason from the justification end backwards to distinguish which part of the report is reliable? That is, can you say, if part of the report is justified, that part was reliable; if part of the report is unjustified, then that was the unreliable part? I don't think so. It could still be that no part of the report is reliable.

(3) is just inconsistent with (1) and (2).

I understand that you're frustrated, because you're experiencing some of the weirdness of propositional logic for the first time.

I'll make it worse for you.
Let LH="Pippen has a left hand" and RH="Pippen has a right hand."
See if you can prove the following: (LH→RH) ∨ (RH→LH), with no other premises.

You want to say that having a left hand doesn't entail having a right hand and vice versa. While that's undoubtedly true, it's not really something material implication (→) all by itself is suited to express, as you should have just discovered. Happily ☐(P→Q)∨☐(Q→P) is not a tautology.

Material implication is odd, and takes some getting used to, because it is always true when the antecedent is false. That's useful for doing lots of things, but it's confusing when you're trying to express things like causal connections, for instance.

Here's one way (I learned from Michael Dummett) to think about it: material implication is more like a conditional command than a conditional bet.

Suppose you make the following wager: "If Brazil is in the finals, they will win the World Cup." If Brazil is beaten in the semi-finals, your bet never takes effect and you are not rewarded. (Analogous to False.)

On the other hand, if your mother tells you, "Do not leave the house without wearing a coat," you could rephrase that as "If you leave the house, wear a coat." In this case, not leaving the house counts as obeying the command. (Analogous to True.)

WIYF.

Non-referring words can have a meaning (e.g. the word "and"), and words can mean different things but refer to the same thing, e.g. "the father of Elizabeth II" and "the son of George V". — Michael

"and" refers to the addition of other things. — Harry Hindu

Does the phrase "the addition of other things" also refer to the addition of other things?

When expressions refer to the same thing, you should be able to substitute one expression for another salva veritate, in non-intensional contexts at least. So the following are equivalent in truth-value:

(1) The father of Elizabeth II was King of the United Kingdom and the Dominions of the British Commonwealth from 11 December 1936 until his death.

(2) The son of George V was King of the United Kingdom and the Dominions of the British Commonwealth from 11 December 1936 until his death.

You may not know those are equivalent in truth-value, but we'll leave that aside for now.

Are (1) and (2) equivalent in truth-value to the following?

(3) The father of Elizabeth II was King of the United Kingdom the addition of other things the Dominions of the British Commonwealth from 11 December 1936 until his death.

(4) The son of George V was King of the United Kingdom the addition of other things the Dominions of the British Commonwealth from 11 December 1936 until his death.

If not, why not?

I said that if we are able to talk about something then it must exist in some form. — WISDOMfromPO-MO

I get what you're talking about it here; I just don't think it's the best approach. You're thinking of existing "as an idea" or "as a concept" or "as a social construct" as the sort-of fall-back position for things that don't physically exist. So, Santa Claus and Harry Potter exist "as ideas," or something. And that seems to make sense, because how can you talk about something that doesn't exist?

I've focused so far on that last part, to try to nudge you in another direction. Let's talk about the first part.

Donald Trump does exist, and so do people's ideas about him. Does Donald Trump, besides just existing as himself, as a person, also exist as people's ideas about him? You could say that, but there's not much need to: you can just say people have ideas and some of those ideas are about Donald Trump. That seems to cover everything and there's little temptation to say he also exists as an idea. You can do everything you want--distinguish between what he's really like and what different people think he's like, for instance--without giving him an extra way of existing besides the one he's already doing.

But what about Santa Claus? Here we only have people's ideas about Santa Claus, people pretending to be Santa Claus who aren't (people who sit on a throne of lies), people talking about Santa Claus. Santa Claus does not exist as a person in just the same way that Donald Trump does. But here the temptation is strong to say that Santa Claus exists somehow, because otherwise what are people's ideas about? What do we talk about when we talk about Santa Claus? It's tempting to say he exists "as an idea."

But that doesn't really do what you want. Now that you have Santa existing as an idea, what do you do with that? Can you say what people's ideas about Santa are about? It doesn't look right to say people's ideas about Santa are ideas about Santa as an idea, no more than people's ideas about Donald Trump are ideas about Donald Trump as an idea. Children don't believe that the idea of Santa Claus comes down the chimney; they believe a person does that.

We also don't seem to feel this temptation in the same way when we're talking about things that really do exist in some non-physical or abstract way. The United States is a real thing, but it's not exactly physical. Social institutions are abstract. This again is not the same as being an idea, because someone's ideas about the United States are neither the United States itself, nor are they ideas about the United States as an idea. They are ideas about an abstract thing, the United States. The same goes for numbers. The same goes for voices, traditions, habits, migrations, wars. Those are real things, objects you can talk and think about, but still aren't physical things like a car or Donald Trump.

Is Santa Claus one of those sorts of things? Now we have language problems. If you believe, or if you pretend, that Santa Claus is a real person, you have a belief or a pretense, but those are not the thing you are believing or pretending. Those are still just what they are, your beliefs and pretenses. And those beliefs and pretenses are about a person, not something like a number or a concept or social construct. They are about a person who doesn't exist. His not existing does not change what the content of your thoughts and words is.

But in the case of Donald Trump, we want to say that the content of our ideas about Donald Trump come, however indirectly, from the object Donald Trump. Where could our ideas about Santa Claus come from, if what they're about doesn't exist? Of course, for most of us, our ideas about Santa and about Donald Trump come from other people, and we don't have direct access to the object. Some people do with Trump, but nobody does with Santa. What we really want to know is what the very first thought about Santa was about.

Which brings us back to Harry Potter. J. K. Rowling writes a whole book about someone she made up, with lots of other stuff in there she just made up. Fiction, pretending, imagining, hypothesis-- they're all on a spectrum that includes lying. All ways of saying something is so that isn't, or of talking as if something were the case, whether it is or not. I'm just going to point out that the content of a lie has to be exactly what it seems to be and not something else. If I tell you there's a tiger in the bushes, so I can swipe your dinner, I want you to have a belief that there is a tiger in the bushes. The content of that belief has to be [ tiger in the bushes ] for the lie to be successful.

So do you think you could manage an executive summary of the argument? I spotted bits of it here & there in your posts, but I couldn't possibly reconstruct it.

I think it might help make your position clearer. A change of scenery. Anti-reductionism is more or less a lemma for you, so maybe if you just presented the lemma separately, that would be tidier. (I was going to say something about people not having entrenched views about meteorology, but ...)

The statement "A does not exist, period" is contradictory. A must exist in some way, because a person is making a statement about it. — WISDOMfromPO-MO

The issue you're raising right here is known as the problem of "vacuous singular terms," that is, expressions that look like they refer to a real object, that are constructed just like expressions that do refer to real objects, but do not. Your interpretation, that they exist in some special way, is not the only interpretation available. I see the whole thing as a quirk of our language. Okay, maybe more than a quirk, but at any rate I do not feel compelled at all to say that whatever I talk about exists.

The question is if it is possible for something to in no way, shape, form, constitution, state, etc. exist. — WISDOMfromPO-MO

I took this to mean, is there something that not only does not but cannot exist, and of course the answer for me will be, sure.

But for you, if anything you talk about or imagine, or whatever, exists in some fashion, then your question is more like this: could there be anything that cannot even be talked about or imagined? And that is a conundrum. If you know that to be true of something, you'd have thought of it, and there you are, it now exists. On the other hand, if there is something no one can imagine, then no one will. That seems to mean that if there is such a thing, you cannot possibly know that there is such a thing.

EDIT: Hmmm. The phrase "thing I cannot possibly know no one can think of" looks like it refers to something.

It might help if you could sketch the case against reductionism-- I remember finding Fodor's argument pretty convincing in that paper about special sciences, but it's been way too long since I read it.

"Contradicts" has a weird ring to it in this context. Some of the differences here aren't really much like the calculus/statistics distinction.

Some systems, like intuitionistic logic, set tighter restrictions on how you get from A to B. There's a sense in which it "gets along" with classical logic, but some of the things you can't do in intuitionistic logic are things people are pretty attached to.

Using more than the usual two truth-values is obviously more of a game-changer.

Logic can be treated as, in essence, of branch of mathematics, the investigation of structures for their own sake, but many are interested in logic primarily for its usefulness in formalizing reasoning. The standard classical logic was invented expressly for the purpose of formalizing mathematical argument. Some non-standard logics are of the mathematical sort, but many are attempts at remedying perceived shortcomings in classical logic as a tool for reasoning.

You could say something similar I suppose about axiomatic set theory: in some cases, it's just pure investigation, but in some cases the goal is providing a foundation for the rest of mathematics. That means at least one question that naturally arises is just how much of the existing superstructure of mathematics can be built on a given proposed foundation.

That may be a common human experience, and one that I would take you at your word when you say that you've had it.

Interpreting it as God might be understandable, but that doesn't make it any less "crazy" in my sense — Sapientia

And no, if I have had such an experience, I haven't jumped to the conclusion that it was God - I'm not crazy. — Sapientia

This is the part I'm curious about.

Is it your position that (a) one cannot have an experience of God, or (b) one cannot know that one has had an experience of God? You seem to accept that there is something reliable about a person's description of their own experience; but there is also something you describe as interpreting that experience, and this part requires justification.

I'd like to understand how you see this distinction.

We categorically deny that you were ever a member of the Church of the Invisible Pink Unicorn. It's all lies! Lies and falsehoods! And innuendoes! Icky ones, with little thingies growing on them.

You sure you want to go down this road? I can dispatch a team before you get your agent on the phone.

I saw the edit. Your new IPU is make-believe and you know it. Admit your failing, pay the indulgence, and we'll take you back. Oh, there's also a lecture tour where you tell the story of your fall and redemption. And maybe a book. Yes, we will require a book. But that's all.

You can edit your own post, but I will require some consideration to edit mine that documents your weakness.

I am eternally damned! What did I do? — Marchesk

I tried to help you.

Invisible Pink Uniform — Marchesk

infidel

Autocorrect or heretic?

"If A does not exist, how are you able to talk about A?" — WISDOMfromPO-MO

Here is a hypothesis:

(1) If something does not exist, then we cannot talk about it.

It has a contrapositive:

(2) If you can talk about something, then it exists.

I believe (2) can easily be shown to be false, and I believe I have done so in this thread. Therefore (1) is false as well.

If something categorically does not exist, how are we able to talk about it? — WISDOMfromPO-MO

Here is a different hypothesis:

(3) if something is impossible, then we cannot talk about it.

Its contrapositive would be:

(4) If we can talk about something, then it is possible.

It may very well be that the current consensus among philosophers is that (4) is true, because possible world semantics. I'm not in love with PWS, and lean toward (4) being false. "There's no ball of ice at the center of the Sun," feels to me like a statement that cannot possibly be false. Does anything turn on whether that statement is about the non-existent ball of ice?

EDIT: This is silly. Obviously people who make regular use of PWS talk about impossibility too. It just annoys me for some reason. Unnecessary aspersions on the character of PWS hereby retracted.

If you can't communicate like you're having a conversation rather than someone with some sort of logorrheic disorder there is something wrong with you. — Terrapin Station

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Yeah, and it runs pretty deep. There are certain sorts of things people say, certain words they use together, and so on. In chess there are automatic moves. I could analogize here forever. I guess we'll have to give Wittgenstein some credit here, because it also comes back to a shared way of living, not just talking.

I'm proud to say the astrology reference didn't even occur to me.

As far as pure mathematics and logic are concerned, their plurality is not even controversial. — SophistiCat

This is certainly true, and with logic there can even be controversy about different systems because there's already controversy about what the systems are for. Is the same thing true in mathematics? I've just never gotten that sense, but maybe I missed the really juicy controversies. For example, it's my impression that Bayesians and frequentists never end up accusing each other of not really doing mathematics.

For my knowledge, could you give an example of an axiom that would change the classic logic? — Samuel Lacrampe

You could start here.

Nah, "constellation" has this static feel to it. Maybe "convergence" is best if we're wedded to "influences."

(That second sentence is strangely poetic.)

Since we were talking of communication, it might be worth noting how redundancy carried the con-versation my son and I were having-- I knew exactly what he was trying to say, what he meant, despite his extravagantly erroneous word choice.

Yeah I tried to think of all sorts of "con-" words! People even use "constellation" in related ways.

My teenage son once described an album to me as resulting from a "conflagration of influences." I convinced him that was not the word he wanted, though it has a certain metaphorical charm. The problem is "confluence of influences" is hideous, so maybe his brain just refused to let him say that.

I guess I still haven't exactly addressed the question of whether you could be said to be really using a word if you don't understand it. As I tried to indicate earlier, whether you individually use a word, or use it correctly, isn't even directly relevant for theory. It's how the word is used that matters there.

But for you, beyond the training and learning stuff, there's a little that you already do know that entitles you to use the word: you know it's the name of a medical condition, and you know how to use expressions in that class; you know it's something someone with a life like yours could have (it's not like malaria, say); you might know some of the symptoms if that's why you were taking to the doc. And I think the person you talk to would get all that too.

So you're not quite in the position of the congenitally blind person with color-words.

Act as if ye had understanding, and understanding will be given ye, or something. Fake it till you make it.

Except that "Schnarrglop's" is actually the right word. Think about teaching someone to play chess or to use a tool, teaching them any kind of skill. Their first attempts will be tentative and uncertain. "Is this right?" "Yes, that's how the knight moves." (Ain't it funny how the knight moves?) Their understanding is limited, but the training includes them doing something barely right at first. Similarly for the guy you tell you have S. syndrome. If he googles it, he'll have that statement you made to connect his new knowledge to.

Thinking more about what you and @Michael said, there is still this oddity about what use you can possibly be making of a word, or even an entire sentence, that you don't understand.

I do think, as I said before, that this is something you'll often see with people learning a new word. And I think there are obvious limits to how far this can go.

But the other thing to note, following on what @Michael said, is that the meaningfulness of a word or a sentence is not dependent on whether you understand it, even if you're the one speaking.

And that's why "meaning is use" and related doctrines are usually expressed in the passive voice, so to speak. The user that matters for theory is not really you the individual speaker, but a fictive omni-competent speaker.

But it's your particular uses that language is put to, that make using language useful. It's as if you ask yourself, what would the ideal speaker say if she wanted to say what I want to say the way I want to say it?

Surely I'm saying something meaningful, even though I don't understand it. — Michael

Looking back, I don't think I ever said I agree with this.

I think I get what you're saying.

There are lots of occasions where the distinction between what you literally say and what you mean, or what you communicate, matters. Logic is exclusively concerned with what is literally said. Libel law. And we manipulate the distinction in our daily lives by suggesting and insinuating and implying things we don't actually say.

Am I in the neighborhood of what you were asking?

Lol. I was confused.