It seems that the caravan has moved on while I was away. But thank you both for making me think through what I was saying.

If Aristotle, and perhaps Homer, never actually existed, yet Aristotle and Homer are rigid designators, then what is Aristotle and Homer actually designating. — RussellA

Well, Homer is the author of the Iliad and the Odyssey. So presumable "Homer" designates that person whoever he may be. The difficulty is not just that someone else wrote those epics, but that they were a) not written down (until long after they were created) and b) not created by a single author. The poems were part of an oral tradition in which each poet created their own version(s), so b) our ideas of authorship and texts do not apply in that culture. I wouldn't press this as any kind on knock-down argument here. It's just an interesting conundrum.
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That would be very interesting if you could explain a reasonable difference between these two. The former would be an actual predication, the latter would be an imaginary predication. Is that what you're saying? — Metaphysician Undercover

It's easier than that. Existence is not a predicate. I'm not quite sure whether being imaginary counts as a predicate, but there's no doubt that "imaginary" excludes "exists". What does exist (in our world) is the account that people give of what they have imagined. Whatever has been imagined would then count as a possible object, and so existent in another world, not this one. Yes?

Perhaps we don't need a theory about the nature of possible worlds in order to use modal logic to regiment modal discourse. An open rather than a close approach. — Banno

It so happens that I think that many, though not necessarily all, questions about the nature of things are ill-formed, because what is meant by nature is not well-defined in the relevant context. So I am extremely comfortable with that approach.

However, Kripke argues for necessary a posteriori knowledge, that some truths can only be known through empirical observation. Therefore, even though my knowledge of Aristotle may be totally false, when I use the name Aristotle, it is still a rigid designator because the name still refers to the actual Aristotle. — RussellA

So is the name "Homer" a rigid designator in this case?
Wikipedia - Homer,

This conflates possibility with potential. It's true that, given what occurred, the counterfactual is not possible. But the question is whether or not what occurred was necessary or contingent. — Relativist

Well, my question is how to tell the difference between necessary and contingent. It seems that any contingent statement becomes necessary if the relevant conditions hold. I don't see that distinction as particularly interesting.

That you do not have at hand a definite description of Aristotle does not make your reference fail. The person you are mistaken about is Aristotle... the reference still works, even in near-complete ignorance. Indeed, there are examples in the literature of reference working in complete ignorance. — Banno

I'll have a look at Donnellan and see. There's something going on here that I haven't pinned down.

“Learning” smuggles in a representational picture: as if what is transmitted along the chain is a mental grasp of an object. That’s exactly the picture Wittgenstein is trying to loosen. On his later view, what is transmitted is not knowledge of a bearer but participation in a practice. Hence my suggestion. — Banno

Oh dear! That was so far from my intention that I lost sight of the possibility. I thought everything that I said emphasized knowing how to use the term.

I probably should not have mentioned the fiction argument at present. It works by rejecting maximal consistency, which has it's own consequences. They may be treated as partial, consistent worlds. Poor pedagogy on my part. But it's were we might go.... — Banno

It wasn't your fault. I brought the topic up, in my innocence. But I think the issue here is what the limits of possibility are and the complication is that there are different limits at different levels. For example, it is not physically possible that the sun does not rise in the morning, but it is logically possible. Whether it is possible to imagine such an event is different again.

Yes, but the same could be said for any so-called "possible" world one entertains with the semantics. If I had my way, we'd distinguish between fictional and possible worlds. — Relativist

I don't disagree. I made the connection because I thought the analogy/similarity between fictional worlds and possible worlds made it easier to understand the latter. I underestimated the difference.

I agree that there is this difference between a fictional world and a possible world, that the possible world might or might not exist - become actual, if you will...
— Ludwig V
Only if it pertains to the future, and is consistent with the history of the world up to the present, and everything else we know about the world. — Relativist

Well, "it is possible" does pertain to the future, because it is in the future that the possibility resolves. If it is possible that I win the race, I win or lose the race in the future. Past possibilities - "it was possible" - are, by implication resolved and I have already won or lost. I do think that, like probabilities, the future is part of the concept.

However, when entertaining counterfactuals about the past or present, the implication is that this counterfactual world could possibly have happened. But could it? This is analyzable and debatable. It's a very different debate if we're simply examining the coherency of a fictional world. — Relativist

It is tempting to agree that counter-factual is a possibility. But the game of alternative history suggests that a counterfactual does not contemplate a possibility, but an event, whether it is possible or not. "How would things be now if Hitler had won the war?" Since he did not, it is not possible that he did. Yet somehow we can contemplate that eventuality and build a coherent story from it.

That's the role of w₀. You answered your own question, I think. — Banno

I'm glad you agree with my answer. It gives me confidence that I'm not thinking rubbish.

I've again got "A nice derangement of epitaphs" in the back of my mind here. A reference is successful if the enterprise in which it is involved is a success. — Banno

I wouldn't quarrel with that. I wish I could get hold of the article, but the only source I found wants £55 for a copy.

I am assuming that each possible world will have a similar recursion and therefore be capable as functioning as a world of origin. Yes?
— Ludwig V
Yes. — Banno

So each world serves as the origin of its transworld identifications. Which world is the origin depends on which world we are in. Each world is the actual world in that world.

This is a different point, further complicating the issue; that since in the actual world Tolkien developed Frodo as a fictional character, we might decide that Frodo is necessarily a fiction - a fiction in any possible world in which he occurred. What this would mean is that were we to come across a small hairy man with nine fingers who was a friend to the elves and wizards, that would not be Frodo, because he is actual and Frodo is a fiction. — Banno

I think that works for this case. But fictions are a varied bunch, so a story about a real or possible person in our world might well count as a possibility and what you say here wouldn't apply. What about stories that mix real and fictional characters and/or places?

What you learned is irrelevant. You heard someone use the word Aristotle, and you started to use the word; and crucially, you would be talking about Aristotle even if what you think you know about him were completely wrong. — Banno

H'm. I'm working this out as I go. You have a point. But I'm inclined to say that other people would take me to be talking about Aristotle. I, on the other hand, don't know what I'm talking about. But there is an objectivity here. The interpretation of people in general determines what is the case, so it is not wrong to say my deviant use is wrong.

(Remember - what preserves the causal chain is people using the tag.)
— Ludwig V
Yes! And that alone! — Banno

But surely the causal chain is a chain of people learning to use Aristotle in that way. I agree that one person does not determine anything.

If you overheard the bloke on the TV say that Aristotle Taught Alexander, and assumed he meant that Aristotle taught Alexander Graham Bell, and that was all you knew about Aristotle, you would be mistaken, and importantly, you would be mistaken about Aristotle. The reference works despite all you know about Aristotle being wrong. — Banno

Yes. But the causal chain is a chain of people learning to refer to Aristotle correctly. Isn't it? What else could it be?

1 - For me, the name Aristotle is a tag to what I learnt about Aristotle.
3 - There is a reality to Aristotle in 350 BCE, even though I may not know what it is. — RussellA

1. What you learnt about Aristotle enables you to refer to Aristotle - to use the tag. (Remember - what preserves the causal chain is people using the tag.)
3. Yes. It is that reality that enables Kripke to pass off "rigid designation" as a real thing. It is what enables other people to think of Aristotle even when a parrot or speaking machine says Aristotle. Nonetheless, the link is established by the continuous use of the name by people who understand it.

iii) “There are possible concrete worlds other than ours” presupposes that there are other concrete worlds
iv) “Possibly there are concrete worlds other than ours” does not presuppose that there are other concrete worlds — RussellA

That's perfectly clear. Thank you.

We produce a fictional idea, a possibility, then to make it fit within the possible worlds semantics, we assign concrete existence to it. This is unacceptable, to arbitrarily, or for that stated purpose, assign concrete existence to something completely imaginary. — Metaphysician Undercover

No, we don't have to assign existence to it. All we have to do is to imagine or suppose that it exists.

There is no logical problem with imagining something as being actual and concrete. — RussellA

Quite so.

"May not a paranoid's delusions of persecution be frighteningly coherent? May not a patient's faith that a mere placebo is a wonder drug be therapeutically useful? Russell was quick to claim in opposition to Joachim that multiple systems of beliefs may be internally consistent, though incompatible with each other. Nietzsche had already suggested well before James that false beliefs may be not merely useful but indispensable for life. "
--Truth -PRINCETON FOUNDATIONS OF CONTEMPORARY PHILOSOPHY ; Burgess & Burgess, pg 3 — Relativist

I wouldn't disagree with any of that or with the familiar point that none of those uses or benefits is a substitute for truth.

The book establishes a fiction. We could examine this fictional world for coherence, and draw valid inferences if (and only if) it is, but the inferences are all qualified by, "within Tolkien's fictional world...". But no unqualified objective truths can be inferred. — Relativist

That's true so far as it goes. But the existence of the book does establish that there is a fictional world in which.....

And critically- nothing here establishes the hobbit world (in toto) as anything more than a fiction, so calling it a "possible world" is misleading. — Relativist

I agree that there is this difference between a fictional world and a possible world, that the possible world might or might not exist - become actual, if you will, but we know that the events in LOTR could not possibly take place. On the other hand, many stories seem entirely possible - and there are docudramas. Characterizing the verisimilitude that is required to persuade us to suspend our disbelief is not easy. Aristotle, if I remember right, uses a word that is translated as "plausible". Is that better?

Not within the logic. We might do that when we give the edifice an interpretation. — Banno

Oh, yes. I'm happy to respect the distinction. I may not always understand it.

So, if there exists possible worlds, are they all existing together as a collection in some world that contains them all? — QuixoticAgnostic

That's not quite what my analogy of the bookshelf of possible worlds proposed. It is the descriptions of all the possible worlds that exist in our world. What the descriptions describe or refer to is something else. Where they exist, in my opinion, is not a question that has an answer. Compare this question with "What happened before the Big Bang? Where did the Big Bang happen?" It is not possible to define a framework that could enable a normal answer to be given. Similarly, but differently, those questions about Middle Earth are unanswerable. Fiction is a curious and paradoxical business. It works very hard at what we might call verisimilitude while at the same time denying that anything in them is real - except, confusingly, those elements of reality the authors insert into the fiction. Our ability to immerse ourselves in these worlds ought to be astonishing, but is too much part of our everyday lives to be noticed as such. It's no wonder that sometimes people don't know where the boundaries are.

Kripke’s solution bypasses any metaphysical problems as to the essence of Aristotle. The name Aristotle is just a tag to something else, and in this case that something baptised Aristotle. — RussellA

Yes and no. A name is not like a tag, though a tag is, in some ways, very like a name. Both serve us as ways of identifying things and people. But what maintains the connection between name and named is the use of both. It is handed down from one person to another, and that is the connection Kripke identifies. But this means that anyone using the name needs to know what and who Aristotle is, so it is very odd to say that the link between name and named exists even if no-one know about it. It seems plausible because we - the audience - know what we need to know.

Aristotle is necessarily Aristotle even if no one knows it. An instance of necessary a posteriori. — RussellA

I find that remark almost impossible to understand. Such understanding as I have of it rests on my knowledge of who and what Aristotle is.

Anyway, note that the name of that individual in w₀ - Aristotle - is used as a rigid designator in order to stipulate the very same individual in a different possible world in which he is called Barry. See how the designation w₀ functions in this game? It's the from where that the rigid designation is fixed. — Banno

Yes, I get that. But that gives w₀ a special status that differentiates it from all the other possible worlds. I suppose, though, that one could point out that for someone in that different possible world in which he is called Barry would make the same claim, with the names reversed. So who a name refers to depends on what world one posits as the world of origin. My question is, whether the system can work without positing some world as the world of origin.

I hope we might leave the theory of reference to one side - we have enough distractions. But I might just suggest that there does not appear to be any reason to think there must be One True Account of reference - there may be many ways in which we can use a proper name. What is salient is that Kripke and Donnellan showed that proper names do not always and only refer in virtue of an attached definite description. — Banno

I wouldn't argue with any of that. The idea that there may not be One True Account of reference seems very plausible to me.

The claim that “there is a possible world in which hobbits exist” amounts to nothing more than the claim that the predicate hobbit is satisfied by at least one object in the domain of some world. No commitment follows to hobbits existing outside that domain, nor to their being actual, concrete, or real in any further sense. — Banno

Quite so.

It's a neat point to put pressure on. The simple answer is that the possible worlds are in w₀, the actual world. But all this means is that it is we, in this world, who are talking about them and quantifying them, and they are in our domain of discourse.
What looks a bit paradoxical is actually a recursion. That recursion enters when we describe all possible worlds from the standpoint of a particular world — that’s the “loop” that looks tricky, but it isn’t a real contradiction. — Banno

I am assuming that each possible world will have a similar recursion and therefore be capable as functioning as a world of origin. Yes?

There is a difference between saying “there are possible concrete worlds other than ours” and “possibly there are concrete worlds other than ours.” — RussellA

I've puzzled about this a great deal. Can you explain the difference to me?

Another way to ask this: what is it that establishes the truth of the statement, "there is a possible world in which Hobbits, Trolls and Orcs exist" — Relativist

Why isn't a copy of the book(s) enough?

Ludwig V is right to point out that whenever we speak of "owning" somebody or somebody's life, unless we do mean slavery, there is something odd about this sort of speech. — Gregory of the Beard of Ockham

There is indeed something odd. I think there are two aspects to it. The first is fairly straightforward "A owns B" asserts that A has the means to control B and is not inhibited from exercising it. The second plays of the implicit reference to slavery and suggests that B is a lesser person as a result. It is like calling a human being an animal. In one way, it is a fact, but in another, it is an insult.

It is not univocal with "owning" a car, a house, a picture, or even a pet. — Gregory of the Beard of Ockham

I agree. And it is even less univocal with "I own my own life". But perhaps the point here is to assert one's right to decide whether and when I have the right to end my own life. The bad news is that it is not an argument.
Perhaps, in some contexts, the relevant part of the metaphor is the assertion that I do not own my own life. The implicit claim is that there are some decisions about my own life that I do not have the right to make. This may well be true, in the sense that we all have responsibilities to others, in one way or another. But it does not follow that there may be circumstances when those responsibilities fall away, as when I am no longer able to meet them.

For my own part, the possiblism/actualism debate is much ado about very little. — Banno

I find it keeps slipping from my grasp.

What we don't have here is any inconsistency... — Banno

It wasn't that I saw an inconsistency, it was just that I didn't see how it fitted together. However, doesn't the idea that we can choose which world is actual conflict with the definition of "truth simipliter" as "true in w₀"? Or, better, if we choose to locate the world in which we construct the possible worlds in w₀, (which isn't a problem in itself) doesn't that conflict with the idea that we find ourselves in that world, and do not choose it. That's why I've been trying to locate that move in a different context from the choices we can make about other possible worlds. Don't we need to mark a distinction between that world and any world we choose to treat as actual for purposes of logical analysis? just labelling it metaphysical doesn't explain anything unless we have a good definition of "metaphysical".

Sea water >96% H2O unsafe to drink
Purified water >99% H2O safe to drink but long term use may deplete essential minerals
Purified heavy water >99% D2O ok to drink in very small quantities but very hazardous in larger amounts
All use the term “water” but there is no common essence between them. — Richard B

I don't have a problem with this. It all goes back to the concept of a game as a network of common elements - more like a rope (which has no thread running through its entire length, but is composed of shorter threads that overlap and interlock) than a filament (like a fishing line) which isn't made up of strands. But it's not an actual argument, more of a challenge. On the other hand, so far as I know, no-one has yet risen to it, so it is very persuasive. Kripke is the exception here. No doubt he would sweep it under some carpet. But that doesn't mean it is not true.

Contingent
A modal variability across worlds, something is contingent if it exists in some, but not all, possible worlds. And similarly, sentences are contingent if ◇P ^ ◇~P. If it exists in all possible worlds it is necessary. If it doesn't exist in any world, it is impossible. — Banno

So what do you do with Kripke's Aristotle that necessarily names Aristotle in all worlds in which Aristotle exists? (Is it really impossible that Aristotle could not have had some other name, if he was born at the right time of the right parents and did all the right things?)

So, if there exists possible worlds, are they all existing together as a collection in some world that contains them all? — QuixoticAgnostic

Yeah, and it doesn't help when folk throw "concrete" into the mix... — Banno

Oh, very good. Concrete is the mix.

Seems to me that the answer is to understand "actual" as an indexical. It's our world. It will change as "our" changes. — Banno

That's a good idea.

But I'm bothered by the facts a) that the actual world is the one in which we are constructing the possible worlds and the point of view from which we are surveying them and identifying which world we wish to treat as actual and b) that we do not choose that world - we are lumbered with it - even thrown into it.

I think this is what you mean when you say that the issue is metaphysical. However we classify it, it looks as if we can ask the question which of my books describes it. But we cannot choose that book, only recognize that it has a certain relationship to the world in which I am surveying the books. It would invole self-referentiality, but I think you have already accepted that.

I'm trying to explain this by positing two different contexts (points of view) - the context of the world according to modal logic and the context of ordinary life. It's not a problem unique to modal logic or logic in general. It's a problem for physics as well. Perhaps even for philosophy.

Oh, yes - I emphatically agree - natural language comes first; indeed I'd suggest that formal logic is just a game within our natural language, and not something seperate from it. — Banno

It does seem that we are on the same page after all.

So, what conclusions do we draw here? — Banno

I don't know about conclusions. However, I do think that a practice that pays attention to cases and sometimes is happy to jump one way and sometimes the other is all that is appropriate. (I like Wittgenstein's ideas of a) a map - knowing one's way about and b) philosophy as giving peace from certain kinds of torment - notably the torment of being bewildered in a world that ought to make sense.
I would put in a word for fun and curiosity as well.

I do not see the problem; could you say it in another way? — NotAristotle

All the talk of "Aristotle" referring to Aristotle is all very well - if the metaphysical link is all that matters. We can agree that the link exists, in some sense. But "Aristotle" has another life, in language and the use that people make of it. A referential link that obtains whether or not it is known to language users will not explain how language works, or, more accurately, how we make language work. Note that without language and its speakers, metaphysical truths cannot be formulated, never mind communicated.
Does that help?

What does “water” mean? "Water" means different things to different people. To a scientist, "water" is necessarily H2O. To me, "water" is necessarily wet, in that if not wet it cannot be water. To a linguist, “water” is necessarily a noun. There is no one meaning of “water”, though each meaning is necessary within its own context. — RussellA

And yet all these people can communicate. How is that possible? There must be common elements to all these different meanings that enable communication across contexts. Those common elements are what we might call ordinary life, which is the common context that links all three people.

The challenge is to use formal grammar to exhibit the incoherences and inconsistencies in our philosophical meanderings. It's not picking a logic that gives the answer we want, but looking at what we have to say using formal tools that set out clearly the problems. — Banno

A standard of clarity. Tempting, very tempting.
But you quoted Austin -

"Real" is best treated as Austin suggested, as a relative term - it's not real, it's a counterfeiter; it's not real, it's artificial... and so on. — Banno

I think he would have take issue with you. So perhaps I can suggest that things are not anything like as clear as you seem to propose here.
Ryle, in "Dilemmas" draws an interesting distinction between technical and untechnical concepts, which clarifies, to some extent, his talk of parade ground language and informal logic. The point about ordinary language, for him, is that it is inescapable and even technical concepts rely on it. To put it another way, formal logic starts from ordinary language, which remains basic to our understanding. Formal languages are in that sense parasitic. (Scientists, mathematicians, logicians all live and work in the ordinary world,)
Surely I don't need to try to summarize Wittgenstein's critique.
Which is not to say that formal logic never does the job you identify for it. Whether Russell's theory of descriptions is correct or not, it is, to my mind, a good example of what can be done.
But formal logic has problems of its own. The logical explosion (ex falso quodlibet - from a false proposition anything follows) is a good example - to my mind, at least.
Even modal logic has issues. Trans-world identity seems to be one of them.
Perhaps that is enough for present purposes.

Water is necessarily H20 even before anyone knew that this was the case. — RussellA

Well, you/Kripke have your reasons for saying that, I suppose. But it is clear that whatever "water" means is not based on that information.

Aristotle is necessarily Aristotle even if no one knows it. — RussellA

Again, perhaps so. But it follows that, whoever is called Aristotle is not necessarily the philosopher that we know and love.

Well if they aren't using the term the same way I would think that they would not get the meaning. If the meanings of the speaker diverge, they cannot have a discussion; but this appears to be something like a rule of conversation (see rules of conversational implicature by Grice). — NotAristotle

But Kripke thinks that those are the possible ways of fixing the reference of any term. So the whole practice of referring becomes pointless.

It is a separate question how such speakers come to agree on the meaning of a term. — NotAristotle

Yes, but isn't this the question that matters. A reference that cannot be used is utterly pointless.

For the Indirect Realist, we only know the actual world as representations in the mind, .... — RussellA

Clearly, I'm not a indirect realist, because I don't accept that we only know the actual world as representations in the mind, because, as Berkeley pointed out, unless you can compare a representation with its original, you can't establish what, if anything, it is a representation of.

...whereas for the Direct Realist, we directly perceive an actual world existing independently of our representations of it. — RussellA

Clearly, I'm not a Direct Realist because I don't accept that we directly perceive an actual world existing independently of our representations of it.

I don't think that "directly" and "indirectly" are applicable in this context and I have my doubts about "real", because "unreal" in this context does not have a clear meaning.

That Aristotle is the same individual is not because of any knowledge about his essence or identity, but because of a casual chain linking Aristotle back through time to being the son of his parents at the moment of his baptism. — RussellA

The implication is that the existence of the causal chain is necessary and sufficient, presumably whether or not we know it. That's extremely hard to understand, because it suggests that we do not necessarily know who Aristotle is, if anyone.

IE, it is wrong to say that there are actual possible worlds. — RussellA

I would agree with you if you mean that the idea of a possible possible world is incoherent. But all possible worlds are possible actual worlds. When we designate one of them, we are making that possibility actual. We do not make the possible world vanish and an exactly similar, but numerically different actual world appear.
The candidates in an election are all possible office-holders. When one of them wins, that very same possible office-holder becomes an actual office-holder. It is very confusing to think of that office-holder as an actual possible office-holder, but very easy to think of that actual office-holder as an erstwhile possible office-holder.

The take-away: the structure of possible world semantics that Kripke set up has been used to formalise a wide variety of situations by amongst other things constructing suitable accessibility relations. Since these are dependent on the core possible world semantics, it might be good practice to make sure we understand what that is before we go off talking about these applications of that logic. — Banno

I think I understand all that. We seem (not only in this context, but in most modern discussions of logic) to have got to a situation where what logic one uses is just a function of what project one is pursuing. Logic as pragmatism. Is that grossly unfair?

In other words, if my composition of H2O and NaCl is what determines what I am referring to, then yeah, that would also determine what is meant by water. On the other hand, if what I mean by water is in some sense prior to or co-relational to the thing in the world that is being picked out, then I am not so sure that we have to use the actual-world instantiation of something when we refer. — NotAristotle

It looks as if you are saying that what determines reference is simply a question of how each speaker is using the word. I can see a sense in which that is true. But then I want to know how it is that other people can "get" what I am referring to, given that they may or may not be using the word in the same way as the speaker.

There is no need to appeal to essences in all possible worlds to understand what the name is referring to in this example (sc. "warder" is s composed of 98% H2O and 2% NaCl). — Richard B

It does seem obvious that the way a community refers to something cannot be determined by all possible future discoveries about that substance. We have to adapt how we refer to things as we go along - future cases are determined as they crop up. It seems to me that rigid designation sweeps away all the problems in pursuit of the timeless present.

This is the problem Kripke has with using the natural language term "water" and trying to call it identical with the scientific term "H2O". His only choice is to massage that vague term "water" into a precise term like "H2O" to fit in with his domain of logic. — 'Cartesian Linguistics' - James McGilvray

That's exactly right. But I would say that "massaging" our meanings is how we manage things. Our critique ought to not to target the massaging, but the sad consequence that we end up with a misleading view of our world.

I think the real answer here is it does not matter what you say, only what we humans agree upon. — Richard B

I would agree. But we need to give more of an answer to those who think it does matter. There is what may be a side-issue, but we need to be aware that just as there are many things that humans agree on, there are also many things that they disagree on. Paradoxically, human agreements may also be the frame of human disagreements.

No, that's not what contingent means. Suppose necessitarianism is true. Necessitarianism is the theory that every that event that occurs (past and future) occurred necessarily. — Relativist

I agree with you. Necessitarianism does seem to sweep the concept of contingency away. So we need to show why we need it. I don't have an answer.

Actual worlds may exist or possibly exist. — RussellA

We have to be very careful about our terms here. As a result of reading this thread, I have become quite confused about what "actual" actually means (!) and how it relates to "exists" (and "real"). I don't see how actual world could only possible exist. It seems to mean something close to "exists" and like it, in that neither are, in Kant's sense, predicates. (Nor, come to think of it, is "real")

But let's forget about that." -Naming and Necessity p43
If he can't account for identity over time, then he can't account for true trans-world identity either — Relativist

I think you misunderstand Kripke's project. It is, it seems to me, to find a way of forgetting about everything that makes a problem for the project of logic. In which, perhaps, he succeeds. Then we will ask more pragmatic questions about the project.

...every concept we have misleads intellectually by producing the illusion that something not understand is understood. — RussellA

I think that's far too strictly binary. Understanding is not a whole, but is (almost always) partial. No single concept can cater for all contexts, but they can be useful and helpful in some contexts. That is enough.

Well, since we were talking about suicide, I thought it understood that we were talking about the life in question. Sorry for the imprecision. — Questioner

Not an unreasonable assumption. But I wanted to put owning a life into a context that made it clearer, IMO, how absurd the idea of owning one's own life is.

Just a note - if it's assisted death we are talking about, it is not referred to as euthanasia, which removes the agency of the person making the decision. — Questioner

You are right. I'm a bit old-fashioned and forgot about this.

Who owns a life?
Do obligations to others supersede that ownership?
Is interference in one's desire to kill themselves morally sound? — Questioner

1. The question is badly formulated. If someone owns a life, that is slavery. The idea that I might or might not own my own life is meaningless. But if you are asking, who has the right to make decisions such as ending a life, it seems crystal clear to me that only I can decide to end my own life. What about capital punishment? I oppose that. What about the life of someone who is not competent? That's much more difficult. But this thread is about suicide, so those situations are off topic.
2. DIgnitas are very clear that people contemplating their euthanasia should talk to their nearest and dearest and do their very best to persuade them to accept their decision. But there's a corresponding obligation, I think, on relatives not to unreasonably oppose it.
3. It depends on the details of the case. But sometimes it is not - and sometimes it is.

I don’t know if that’s true. I am currently well and healthy, but I want to retain the option of ending my own life if circumstances deteriorate. If I were to develop a terminal illness that involved significant suffering, I would want that option available. — Tom Storm

Me too.
I have heard that in Canada, it is not unusual for people to go through the procedure for euthansia but never use it.

DIGNITAS’ experience shows that only a very few people who enrol as members take advantage of the service for assistance with suicide. They usually feel sufficiently protected by the Patient’s Instructions. If these are observed – because they specify that no life prolonging measures are to be initiated – any life-threatening situation will lead to a natural death. Membership of DIGNITAS endows members with confidence: in the event of a hopeless situation, a member can say “I have had enough now, I want to die.” This feeling of security is of exceptional importance to mature human beings. — Dignitas Information Brochure

Don't forget about the instruction not to prolong life unnecessarily. It has legal force in many countries, though it goes by different names.

I read Naming and Necessity some years ago. Later, I read Mackie's How Things Might Have Been*. The latter was written after Kripke's work; she references Kripke, Lewis, Plantinga, and others - and demonstrates the problems I have been relating to you. Responding, "but Kripke said...." is not a refutation. — Relativist

H'm. I thought @Banno was only aiming to explain Kripke's system as being the one that is most widely accepted in the relevant discipline.

trans-world identity is controversial. Kripke does not solve the contoversy- he just alligns to one side of it. — Relativist

That's one of the reasons I can't accept the possible worlds device as anything but a way of making a formal logical system for possibility and necessity. Kripke sweeps away all the philosophical problems by inventing rigid designation.

This is the issue Banno and I debated endlessly in the other thread. The position that Banno insisted on, which I insisted is clearly false, is that the actual must be possible. This means that the actual world (and this is the factual "actual world") must be a possible world. — Metaphysician Undercover

It seem that you and @Banno had incommensurable views. He was explaining Kripke's views, and I've benefited by getting a better understanding of what those views are. But to understand K, I think you have to understand what he is proposing. I proposed earlier that we think of the description of each possible world should be thought of as a book on a shelf; then the description of the actual world can be placed on that same shelf and thought of as a possible world along with all the others. We can take any book off the shelf and think of it as the actual world. So any world can be thought of as a possible world and that same world can also be thought of as the actual world.
Think of it this way. You are being asked to set aside the world as you know it and think about a different world. One's thinking in this mode involves suspending (bracketing) one's normal beliefs and disbeliefs. So, the world in which one is performing this thought experiment is set aside. While you are experimenting, we think of that world and the goings-on in it, as real. When we switch back to normal life, the actual world, in which all those books exist and we choose to take one off the shelf becomes, again, part of our thinking.
You may be thinking that this is all just pretending, but it is something was can do. It is how fiction ("Pride and Prejudice" or "Star Wars") works. You probably know Coleridge's phrase about the suspension of disbelief and his recognition that in some ways it is special, even weird. But it is clear that we can do it.
I don't think there is much difference, though, between thinking about a different world, in which, for example pigs and horses can fly and imagining that pigs and horses can fly. Kripke seems to think not.
That's why he proposes that we treat all possibilities in this same way. So perhaps we should only think of this as a fancy way of thinking about what would have been different if Nixon had lost the election. If it works for his project, it is justified.

Since possibilities can be boundless, any set of possible worlds which we produce can never be "in fact the set of all possible worlds". — Metaphysician Undercover

If possibilities can be boundless, it follows that they might not be. In that case, we can produce a set of all possible worlds. But we can define the set of all natural numbers, prove that it is infinite, and still calculate.

The possible worlds we present, are really ideas which we produce. But it is implied that there is an independent set of all possible worlds. — Metaphysician Undercover

The distinction between an idea and what it is an idea of what is sometimes called it's object, even though it may not be an object at all in the other sense of the word, is implicit in the idea of an idea. You seem to confuse the two when you say that the possible worlds are really ideas.
To understand this, may I go back to Frodo (just for the sake of an example).

Frodo" refers to Frodo, a fictional character in LOTR. It does not refer to the idea of Frodo.— Banno
A fictional character is an idea, not a thing. — Metaphysician Undercover

This is more complicated than it may appear. An idea is defined by reference to what it is an idea of. The idea has no existence without reference to its object. It is, in that way, parasitic on its object. But in some cases, the object of an idea may not exist, as in the case of Frodo. Here, we are presented with all the descriptions that we normally use to describe something in the world, but there is no such thing in the world. So, does Frodo exist or not? He is a fictional character, and so the answer must be, No. But there is an idea of him, which is created by the stories about him. So the answer must be Yes. Classic philosophical stuff, produced in the familiar way by extending the rules of a language game into a context where standard interpretations do not work, and we must decide how to apply the rules.
What we cannot do is say that Frodo is an idea, because ideas and people are objects of different categories. So we say, for example, that Frodo subsists or some such phrase. Perhaps better is to say that he is a fictional character, which means that he exists in the mode that fictional characters exist in, which, I accept, is to say nothing. In the end, we can work with this paradox without much trouble, so we do not need to resolve the problem, but only recognize it.
:LOTR is a possible world, in some sense of possible. So this problem, and its non-solution, apply to possible worlds, as well as fictional ones.
Do we want to say that possibilities exist or are real independently of our ideas of them? It could go either way. But what we cannot say is that ideas of possibilities can exist independently of the possibilities that constitute their objects. The dependence only goes one way.

The modern logician says, “For all x…,” but when asked what he actually means by ‘x’ he has no idea. He doesn’t know whether imaginary entities count, or whether theoretical entities count, or whether propositions themselves count, etc. In essence he does not know to which of the categories of being his quantifier is supposed to apply, and his presuppositions ensure that he will be unable to answer such a central question. — Leontiskos

I thought the point of modern-style logic was precisely to avoid metaphysical issues. Anything that is distinguishable as a distinct entity (within its category) can be substituted into the formulae, provided a suitable domain is defined for the variables. But the formal system is independent of that definition. Hence Quine's "To be is to be the value of a variable". Which doesn't solve any metaphysical problems, but then, I doubt if it was supposed to. But perhaps I've misunderstood.

Therefore all life on earth has a moral duty to carry on until the old age and inevitable natural deaths. — Corvus

I think that's a little sweeping. Most life on earth doesn't have a choice in the matter. That excludes choice, which excludes morality. (Incidentally, it also rules out the widely respected activity of defending one's family, etc.at the cost of one's own life.)
In fact, the idea that we have a moral duty to carry on until we drop acknowledges that we have a choice. The discovery of suicide by human beings is a radical difference from most other life forms in that respect. One cannot expect to simply rule out the choice if it exists, so the question "why carry on?" needs a response, not a ban.
True, in many cases, thoughts of suicide pass. They may be the product of circumstances or illnesses. But it does not follow from that that it can never be a sober, rational choice. The sceptical "Are you sure?" or "You can never tell what the future might bring" can be appropriate. But if it is not to dissolve into the arid wastes of philosophical scepticism, it needs to be backed up with solid answers - not mere gestures.

Can you imaging a suffering so great in this life that you want to give this life up? — Questioner

I can't imagine that. But I've seen it. Twice.
In those cases, there was no choice available. But if someone in that situation makes a choice, it seems to me to be straightforwardly cruel to try to prevent them achieving their goal. Loved ones may grieve, but active prevention would not be an act of love, but of selfishness.
Now someone will ask me how I know that the choice was a real choice. The answer is, the same way that I know that the choice to stay alive until the bitter end is a real choice, when it is.

On the other hand, I never managed to find the insightful and brilliant in his books, because the first one I read was so dull it put me off reading any others: Musicophilia. My loss, I suppose. — Jamal

I've only ever read "The Man Who Mistook His Wife...".
At the time, I found it interesting, but didn't know what to make of it. Now, I think that there was an important contribution in that he took the mistake out of the joke-book and into a real life. Neither laughter nor condescending pity were enough any more. He belongs with R.G. Laing and the others in his insistence that mental patients do have something to say about their condition that is not merely meaningless noise.

The history of psychology and psychoanalysis is replete with meaningful and insightful works that are not "scientific". Freud revolutionized how we see ourselves and our subconsciouses, but his psychoanalyses have not been found effective in treating psychological disorders. Does that mean they are worthless? — Ecurb

It all depends, doesn't it, on what you think is worthy? "Unscientific" understanding of people involves models that do not align with standard ideas of scientific understanding. Even if there were pills to sort out every mental illness, it would still be necessary to understand the "patient" and their life beyond the clinic. There's no single answer to that, so we need to take on board alternative approaches.

2007. What was that like 5 years ago? Come on man. Imagine if we judged every artist by his or her first work. Imagine the kind of world we would be living in. :chin: — Outlander

Well, yes. But he wrestled with what he was trying to do throughout his career. Everything is a way-marker. No actual conclusions - here is the Sacks method.

one has nonetheless said something metaphysically fundamental! -- indeed, something of great importance. — J

I guess you are right. But I didn't think of it in those terms. It was simply an observation about the conceptual (and engineering) resources we have available.

And yes, we can “understand subjectivity.” But we can only ever be one subject; the only instance of subjectivity we directly know is our own, and that by being it, not by knowing it objectively. — Wayfarer

People often speak as if actually experiencing something gave one some knowledge that was not available to anyone who had not had the same experience - Mary's room. There's supposed to be a puzzle about whether that knowledge is of the same kind as third person knowledge or not. I think it is not, and only dubiously described as knowledge. However, actually experiencing something can make it real in a way that nothing else can. That's not an addition to third person knowledge, but something quite different.
There's a story, possible apocryphal, about WW2. When the US entered the war, a lot of people who had absolutely no experience of the sea or ships were drafted into the Navy. There were problems with sea-sickness. The scientists said that nothing could be done. So a number of them were put on board a ship and taken across the Atlantic, in bad weather. Six months later, there were sea-sickness pills.

According to phenomenology, consciousness is no thing or property that may exist or not exist. “Consciousness” is the misleading name we give to the precondition for any ascription of existence or inexistence. What makes this remark obvious for phenomenologists and almost incomprehensible for physicalists, is that phenomenologists are settled in the first-person standpoint, whereas physicalist researchers explore everything from a third-person standpoint. — Wayfarer

I'm not sure that calling consciousness a precondition for acts of consciousness like "ascription" helps very much. Surely consciousness can only exist when acts of consciousness are possible. But what might it mean to ascribe a motive to someone unless there are other people. How can even ascriptions of motives to myself be meaningful unless they can also be ascribed to others?
It is a puzzle. Third person and first person stand-points seem incommensurable, yet inter-dependent.

The expression 'the primacy of consciousness' doesn't really imply that consciousness is causal. It's more that before anything can be given, there must be a subject to whom it is disclosed. — Wayfarer

You (Bitbol) are trapping yourselves in a binary choice, which does not exhaust the possibilities. In fact, it makes a lot more sense to me to think of consciousness and its (intentional) objects as co-arising.

"Life is meaningless" is surely a mood everyone has felt at some time. How can we fall into such a mood? (other than reading Sartre's Nausea :smile: ). Usually by noticing, often with horror, that the values we hold, and organize our lives around, cannot be discovered in the world in the same way we discover what Heidegger called (in Manheim's translation) "essents" -- rocks and birds and math problems and everything else that has being but not being-there-for-us (Dasein, more or less). But as you say, living as a human is more than that, or at least so some of us believe. — J

Yes, of course that's true. We don't necessarily get it from scientific or other theoretical stances, since it is a methodological decision to treat the world as meaningless; theoretical and scientific projects are not set up to answer such questions. So the experience of meaninglessness is just a part, or a phase, in the meaning of our lives.

Right, Heidegger captures that mood nicely in his idea of Vorhandenheit translated as 'present-at-hand" in its contrast with Zuhandenheit, translated as 'ready-to-hand. When we are dealing seamlessly with the world the ready to hand becomes transparent, and the meaning of things is found in their use as "affordances". The hammer and nails "disappear" when we are in that 'flow' state, and it's when something goes wrong and we suddenly become aware of the hammer as just a brute object, a bare existent, without meaning other than to be analyzed into its components, that we fall into a state of "rootlessness" (my word, not Heidegger's) wherein things become meaningless objects. — Janus

This is a part of Heidegger that I can get my head around, and I think he is quite right.

What makes you think the background mental processing couldn't be programmed? It's algorthimically complex, involving multiple parallel paths, and perhaps some self-modifying programs. But in principle, it Seems straightforward. .As I said, feelings are the only thing problematic. — Relativist

It is a methodological decision to represent our mental processes on the model of the information technology that we already understand. Nothing wrong with that. But it means that feelings can't be represented. They require, it seems to me, a different methodology.

Yes, Kripke suggested "possible states (or histories) of the world" or "possible situations." — SophistiCat

Either would be much better. The possible worlds model seems far too elaborate to me and quite implausible as a description of what's going on.

A model does not aspire to completeness - only to pragmatic relevance. — SophistiCat

Well, completeness is unobtainable, IMO. So why not settle for something we can do?

One shortcoming of modal logic is that it has nothing to say about probabilities. — SophistiCat

I've often wondered how possibilities and probabilities fit together. No-one seems to be interested. But here's an analysis of the possibilities of a dice game when we already have an analysis of the same game in terms of probabilities.

But what if the die throw never occurs? Or a die is lost? Or it balances on its corner instead of landing on a side? And what of all the "extraneous" possibilities - the weather conditions, the configurations of air molecules in the room, the possible ways the Battle of Waterloo could have played out, the possible alternative endings to the Game of Thrones series? — SophistiCat

Quite so. But can't we just lump all these together as "no throws", which is what would happen in real life. Not that we can ever know all the possible outlandish outcomes that might possibly occur.

Kripke himself regretted his choice of "worlds" terminology — SophistiCat

H'm. Did he, by any chance, suggest a better term?

If you continue to insist that you can use the same term to refer to different things, — Metaphysician Undercover

@Banno must speak for himself. But it is possible that he is not doing that. I may have misunderstood, but I think the idea is that the actual world is regarded as a possible world, which does not imply that there are two worlds here.

I don't see that contradiction is ever good. And, I think that might be reasonable as an expressible starting principle for good philosophy. — Metaphysician Undercover

I'm sorry, I wasn't very clear.

When good philosophy is contrary to everyday speech, there is a really good reason for that. — Metaphysician Undercover

This is the context for the remark you quoted. I was referring to contradictions between philosophy and everyday speech, and your acceptance that such differences needed to be justified.

Language on the other hand is a sort of surface feature of the highly developed conscious mind. In other words, beings were living, and developing features which we've inherited, long before we learned how to speak, and these features make a more natural, therefore I believe better, starting point for philosophy. So it is natural that if common speech is producing philosophy which is deceptive and misleading to these inner intuitions which guide us in the will to know, then we ought to reject it as a poor starting point for philosophy. This is why logic is based in placing special restrictions on language, it curbs the tendency to fall back on ordinary language, which misleads. — Metaphysician Undercover

We're getting sucked in to all-or-nothing positions. Ordinary language sometimes misleads and sometimes doesn't. One of the tasks for philosophy is to sort out the misleading bits and those that are not. I notice, however, that many major issues in philosophy are precisely based on misleading features of ordinary language - such as the pursuit of "Reality" and "Existence".
I don't think of language as a sort of bolt-on extra that human beings possess and other creatures don't (on the whole). In the first place, many animals have communication systems that are recognizably language-like and look very like precursors of language. In the second place, language is something that humans developed under evolutionary pressure, and hence no different from any other feature developed in the same way by other creatures. In the third place, you seem to think that our "inner intuitions" are not as liable to mislead us as language is; I see no ground for supposing that.

Might be more of a surprise that □p→(p∨¬p) is also true. — Banno

I hadn't thought of that, but it makes sense. If one element of a disjunction is true, the whole disjunct is true. Presumably, then, we can also write □¬p→(p∨¬p) and (□p→(p∨¬p) & □¬p→(p∨¬p)). No surprise, since □(p∨¬p).

@Banno, @Metaphysician Undercover
An excellent discussion, trembling on the brink of an agreement. I'm biting my nails here.

Keep in mind that the equation he rejects, p→◇p, is valid in both S4 and S5. — Banno

I'm curious. Can we also write ◇p→(p v ~p)? I'm not saying that it has any particular significance for the discussion.

When good philosophy is contrary to everyday speech, there is a really good reason for that. — Metaphysician Undercover

H'm. How to we decide which contradictions are good philosophy and which are not? In other words, there may be a reason for it, but it does not follow that it is a good reason. The point about ordinary speech is that it is inescapable, at least as a starting-point. Specialised dialects presuppose it and develop out of it. That's because ordinary life is inescapable.

There is no logical contradiction in saying that the actual world is a possible world inside the model, while also treating the metaphysical actual world as mind-independent. — Banno

It all seems perfectly clear. I'm thinking of each description that defines a possible world as contained in a book, so that I can line up all the possible worlds on a shelf; I might call it an encyclopaedia. One of those volumes is identified as the actual world; the possibility of being actual is contained in every description, but the identification of a specific volume as actual cannot based on any criterion within the books and from that point of view is arbitrary, Does this make sense?
I had the impression that identification as actual is not based on, and does not cause, any change in the description contained in the book. That is, it is a change in the status of that world, not a change in the world. The actual and possible worlds are not two worlds, but the same world with a new status, in a context that is independent of the books. The other worlds have the status of being possible, which I understand as something like the status of a work of fiction.
The discussion between you and @Metaphysician Undercover seems to me to centre on the question what each of these worlds consist in. I don't see this as a killer problem, because there is no determinate answer to the question what a work of fiction consists in.
There is a different issue about what world my project (and Kripke's) takes place in. Clearly, it must be a God's Eye view. But are they to be contained in the description of each world? If they are, that would undermine the idea that the actual world is exactly the same as all the other possible worlds. But the idea of the God's Eye view seems to be inherent in formal logic, so, again, it is not a killer problem.

The "if any" was meant to acknowledge your point: No answers may be forthcoming, and that could be for (at least) two reasons: We can't find the answer, or the question is badly put because it implies that "how the world really is" is meaningful when in fact it isn't. I'm not sure I know how we would "work out what will count as an answer," exactly, though I rather like putting it that way because it's a reminder that there's probably no way to simply discover the answer. — J

Yes. Questions need to be nested in a considerable web of beliefs. There's quite a lot of different things that can go wrong. The fact that there's so much debate suggests that something is wrong here. "Real" is being used outside or beyond the structure that it usually carries with it.
But sometimes there does seem to be a meaning to it. For example, there is a real puzzle about how to make sense of the physics of colours and sounds in relation to our experience of them - and why not add pain, for that matter. It is, to me, unbearably paradoxical to assert that there are no colours and sounds in the world, and yet colours etc. are not objects in the world. The facts suggest to me that those sensations are produced by the interaction of our sense organs with the world. But then, how to make sense of the fact that we see colours and hear sounds at spatial locations - not in our heads or eyes.

I know, but I deliberately chose an outrageous example so I can illustrate the idea that "point of view" is uncomfortably ambiguous, though it gets invoked constantly in these discussions. As you say, my deluded self has "most likely . . . adopted a way of interpreting the information that you have, so let's allow that it is a point of view." But is a point of view merely a perspective, any perspective? How is what I do when I take a deluded point of view different from what any non-insane, objective, scientifically respectable point of view does? I think it's a lot different, myself, but why? What makes objectivity different from "just what I think"? — J

"Point of view", "perspective", "interpretation", "presupposition" are all involved here. It wouldn't be hard to work out distinct senses for them in this context, and it would help to prevent people over-simplifying things. But I'm just as lazy as the rest of humankind.

Sider doesn't mean grounding in any physical sense. Rather, it's a question of what must be metaphysically fundamental -- what concepts give rise to, or secure, other concepts. Jonathan Schaffer's excellent essay, "On What Grounds What," gives a clear picture of these issues, influenced by both Sider and Aristotle. — J

I didn't think he did. On the other hand, metaphors affect our thinking, so it is worth paying attention to them. However, I don't think that "metaphysically fundamental" helps much. I'm trying to suggest we should pay attention to different kinds of case. Russell's project, for example, was (if I remember right) about the foundations of mathematics. That's completely different from the Wittgensteinian idea that the foundation of mathematics is our practices of counting and measuring things.
Thanks for the reference. I'll certainly look at it.

To conclude: metaphysics as I understand it is about what grounds what. It is about the structure of the world. It is about what is fundamental, and what derives from it.

I have a weakness for reading last paragraphs first. So here we go - three different metaphors in two lines - and still the assumption that any one of them applies universally. ?

I think the question presupposes not so much that there is some way, but that the question can be meaningfully asked, and is important. — J

Presupposing that the question can be meaningfully asked is not the same as knowing how to answer it. Perhaps you are thinking that we can work out what will count as an answer and go on from there. It may be possible, but it doesn't exclude the possibility that it cannot be answered because nothing would count as an answer. On the other hand we can answer lots of questions about the world and, for me, these count as telling us how the world really is. What is puzzling is why you think those answers do not count.

If my point of view is such that aliens have secretly replaced my family, that is not how the world really is. — J

That's not quite what I mean by a point of view. It is a conclusion which you have no doubt reached from some point of view. Most likely, you have adopted a way of interpreting the information that you have, so let's allow that is a point of view. The issue then comes down to your principles of interpretation and how you are applying them. Certainly, it is not likely that a direct challenge to your conclusion will be particularly persuasive. Changing the subject might help.

For Sider, what's fundamental is structure, grounding. — J

Structure and grounding are not the same thing. There such things as self-supporting structures that do not require grounding or even require not to be grounded. Planets, for example, and space-ships.

we're supposed to conclude that the only reason the latter truth is more important than the former is because it reflects our interests and our way of life. — J

I'm open to ideas. Actually, in this case, I would suggest that it is important that "The sum of the angles of a triangle is 180 degrees" is embedded in a complex web of beliefs, whereas "grue" and "bleen" don't seem to be embedded in anything.

So for me it is meaningless to say that our experience gives us no true picture of the real. It doesn't give us a complete picture, but that is a different consideration. — Janus

I can buy that.

*

The problem, I think, comes when we ask which of these points of view (if any) reflect how the world really is. Is there any way to make the case that some points of view are ontologically privileged? -- that is, that they describe the world more accurately than their competitors? — J

The question in the first sentence presupposes that there is some way we can know how the world really is. But there isn't. Or rather, how the world really is depends on your point of view.

If you say "There are no fundamental notions," you have nonetheless made an important statement about what is and isn't fundamental. — J

I haven't said that there are no fundamental notions. In some cases, there clearly are. In other, there don't seem to me. Much turns on what you mean by fundamental.

As to the Wheeler diagram, it says nothing about whether the ways in which the world can be divided up are more or less in accordance with the actual structure of the world. — Janus

We need to resist the temptation to think that there is just one answer. In some cases, how we think of the world does reflect the actual structure of the world. In others, it doesn't.

Individually we inhabit the inner world of our own experience―yet that experience is always already mediated by our biology, our language, our culture, our upbringing with all its joys and traumas. Our consciousness is not by any means the entirety of our psyche. — Janus

No, we don't. We inhabit the world in which we live. Inner experience is what reveals that world to us.

that our usual construals of how the world is are useful because they're true, not vice versa -- but the problem is, truth isn't enough. — J

No, truth isn't enough. But the truths we recognize reflect our interests and our way of life. That's the something more you are looking for.

I gave one example, to view all life as one being, as a starting point, there are many more. — Punshhh

You could start there. But you could also start from viewing the world as one being. But the starting-point will depend on the project, so it's more a matter of what you do next.

I think that shared experience requires an actual world, which is in various ways perceived by all. — Janus

Definitely.

he critiques Galilean science (in his Crisis of the Modern Sciences) for over-valuing the abstract and objective, at the expense of the subject to whom mathematics is meaningful. — Wayfarer

It is true that the new science was set up to remove the subject from the description of the world. But it failed, of course, because the presence of the subject is revealed in the description.

a new approach, as opposed to the orthodox materialism, reductionism, dualism, versus monism etc etc. — Punshhh

I think the problem may go deeper than that. As things stand, if you developed a new approach, a label would be slapped on it, and it would join the list you gave. It's easy to see why - a label is very convenient short-hand and makes it easier to argue about it in the familiar confrontational, binary, ways.

Therefore if we assign to one of the possible worlds the status of "actual world" by realist principles, (which would constitute a modal difference), we would be attributing a difference to this world which violates the modal system which dictates "no modal difference". — Metaphysician Undercover

I don't know what realist principles are. The thing is, there is a system of modal logic which, I understand works reasonably well by the relevant standards. I've no desire to interfere in something I don't understand. So, if the logic says there is no modal difference, I shall treat that in the same way that I treat the logical operators of implication, conjunction and disjunction - as technical concepts which do not need to mirror ordinary language. That mutual tolerance seems to work quite well.
However, it seems that it is not a question of two worlds, with a difference between them, but a difference of the same world. If the difference involved here is not a difference in the description of the possible world, it must be a difference in status of that same world. (Compare Kant's argument that existence is not a predicate, because to assert that X exists is not to identify that there is any difference between X as conceived (or even possible) and X as existent (or actual).

The alternative, non-Platonic realism would say that we create, produce or "construct" knowledge while something other than knowledge is what is independent from us. There are also forms of realism which blur the boundary between these two by invoking concepts like "information". — Metaphysician Undercover

I don't think that any of the critical terms in this debate are at all well defined and there's a wide range of choice available. It can make it very difficult to know just what label applies to oneself.

So we can avoid "annoying debates about what is a thing and what is not", and move along with our mundane communications without the need to address metaphysical differences. If however, metaphysics is the subject of discussion, then avoiding these annoying discussions is a mistake conducive to misunderstanding. — Metaphysician Undercover

H'm. Maybe. I agree, however, that more would need to be said about what "discover" means. But I like the implication that discovery presupposes an independent pre-existing something. It's not difficult with the empirical, but the a priori needs careful handling.

his is formalised by accessibility relations. metaphysically, before the race is run, both the worlds in which you win and those in which you do not are accessible; any might become the actual world. After you win, only the worlds in which you win are accessible. Semantically, both before and after the race is won, we can access both the worlds in which you won and those in which you did not. — Banno

This is hard to decipher into my idiolect. Before the race I can access two possible worlds, the one in which I win and the one in which I don't. After the race, only the world in which I win is accessible. Going by what you said to Meta "One of the possible worlds is the actual world", that world - in which I win - has become the actual world.
I don't understand the bit about semantics, and how they enable me to do something I can't do metaphysically. I think you may be referring to the point that after the race, "I might have lost" is true. ?

So, we must clear up the equivocation in that statement, where "p" refers to a particular, and also to a type. — Metaphysician Undercover

Yes. No more "a possibility" or "an actuality". We'll need to specify whether we are speaking about a particular or a general/universal possibility/actuality.

Strictly speaking it would not be correct to call the unknown "things", because that implies some sort of knowledge of the unknown, knowledge that the unknown consists of things. — Metaphysician Undercover

I take your point. Perhaps we should restrict ourselves to talking of "the unknown". It might clearer to change tack and only talk about the possibilities of discovering new knowledge.

If we look at EricH's example of the coin, there is implied an unknown real thing, the coin before looking at it. But that is not a statement, it is simply something unknown. — Metaphysician Undercover

That's an example of using thing in a generously vague way. It is useful because it avoids annoying debates about what is a thing and what is not, etc;

So while it is not necessarily so (the coin could be tails), something can be both possible and also be real/actual at the same time. — EricH

I'm afraid this doesn't address the problem, but it is a nice try. The possibility and the actuality exist in different contexts. From outside the room, it is possible and from inside the room, not. What's at stake is the P implies possibly P. That means within a single context.

How's that relevant? You change from a specific possibility to a more general, so it is a different referent. — Metaphysician Undercover

So for some p, the possibility of p ends when p occurs and for other p it doesn't. Furthermore, the ending of the possibility of my winning the Kentucky Derby 2025 does not depend on whether I win or lose or even take part. It depends only the the race happening. The disappearance of this specific p depends only on the date, not on whether I win or not.

What I was responding to was unknown true statements, not unknown things. — Metaphysician Undercover

Yes. You are right about that. I took the original claim in a generous senses, that would see it as equivalent "unknown truths"

If we look at EricH's example of the coin, there is implied an unknown real thing, the coin before looking at it. But that is not a statement, it is simply something unknown. — Metaphysician Undercover

So do you accept that there are some unknown things?

Now I can say to myself, "If the actual world was not a possible world, then it could not exist." — Richard B

One of the ways of seeing this is more or less what you describe. One can think of possibility as a kind of ante-chamber to existence. So all sorts of possibilities (possible worlds) hang about in there, waiting to be promoted. It does capture, in a metaphorical way, that our actual world has had a previous quasi-
life.

It seems to me that the what is be said, that "If the actual world was not a possible world, then it could not exist." seems to fall in the latter camp, that it is to say nothing at all. — Richard B

You could say that. It's not exactly analytic, but it is trying to capture (express/show) a conceptual relationship.

The possibility for something, precedes in time the actual existence of that thing. Once it is actualized, it is not longer a possibility, but an actuality. — Metaphysician Undercover

I'll give you this - I cannot win the 2025 Kentucky Derby twice. But that's not because I won it, but because it has happened that the result - win or lose - is settled. But if whatever the result of the 2025 race, it remains possible for me to win the 2026 race. So the possibility of my winning the Kentucky Derby does not cease when I win it.

So while it is not necessarily so (the coin could be tails) — EricH

That's a nice example. But it needs a bit of caution. While I do not know what the result is, I can say "The coin could be tails", but if I say it while I'm looking at the result, I'm falling into the sceptical morass. After you know the result, you need to say "the coin could have been tails".

The existence of statements is dependent on human beings. — Metaphysician Undercover

That's true. But the fact that the existence of the statement that Mount Everest is 29,000 ft high depends on human beings, does not show that the existence of Mount Everest depends on human beings at all. De re and de dicto.

Because the difference is not modal. It's metaphysical. — Banno

I wouldn't argue about that. But I don't thoroughly understand either or metaphysical. So I prefer to say that it's a question of how you look at it - or represent it.

Possible worlds are not independent. — Metaphysician Undercover

I don't understand this. The possibility that it will rain tomorrow does not depend on whether we recognize it. Framing possibilities as possible worlds is something that we do. Compare the platypus, which came into existence independently of is and lives mostly independently of us. How we classify the platypus is up to us.

A realist says the actual world contains true statements that are beyond our knowledge. — frank

The trouble is that we cannot know what they are. So we have to argue that what we already know is not self-contained but leads us to look for and sometimes to happen upon things that we did not know before. I have much more trouble with the idea that there are things we cannot know. I cannot know the exact value of pi, but that's a fact about pi, which I can know. It is not a deficiency of mine.

That the actual world is a possible world is contrary to the realist assumption stated above. — Metaphysician Undercover

If the actual world was not a possible world, then it could not exist.

Seems to me that the notion of accessibility does just this. In a world in which p is false, not-p is indeed impossible. That is within the one world. In other worlds, not-p might be true. — Banno

Neat. Thank you.

The actual world is an abstract object like any other possible world. A realist says the actual world contains true statements that are beyond our knowledge. — frank

If they are beyond our knowledge, they are not statements.

A possible world does not consist of stipulations, so much as a complete description of a state of affairs - which statements are true and which are false. In an informal sense it is convenient to think of possible worlds as stipulated, by setting out how, if at all, a possible world differs form the actual world.
The actual world can for logical purposes be set out in the same way, as statements setting out what is the case and what isn't. But of course the actual world doesn't consist of such statements, nor of stipulations. — Banno

The actual world doesn't consist of statements, although statements do exist in it. The actual world, as the Tractatus recognizes, consists of states of affairs which are what statements refer to, if they are true.
So, going back to the first sentence, it is true that one can define a possible world by describing it, i.e. making a number of statements about it. It is also true that one could describe the actual world in the same way. But this way of defining a world leads us to think of lining up all the possible worlds (including the actual world, of course) and then asking what the difference is. But there is no difference of the kind that we can see in the lists.
But the actual world is the world is the world in which you are carrying out the thought-experiment. To put it another way, although the actual world is exactly like the possible world, in that it can be defined by a series of statements, it is importantly different in that it is actual and the others are not. But this is a difference of status, which doesn't show up in the lists. Compare the difference between the concept of a horse and an actual horse; It is not something that could show up in the concept. Perhaps being actual is like existing - not a predicate.

I would be interested in that.

On Bitbol’s reading, quantum theory supports neither position. .... What it destabilises is the very framework in which “mind” and “matter” appear as separable ontological kinds in the first place. — Wayfarer

We certainly a conception of mind vs matter that not only distinguishes them, but shows their interdependence - co-existence in the same world. The concept of categories was supposed to do this, but it seems to me to posit them as separate without explaining their unity.

Because both dualism and materialism tacitly treat consciousness as something—a thing among other things—while also presuming that physical systems exist independently of observation, the observer problem then appears as a paradox. The realist question becomes: what are these objects really in themselves, prior to or apart from any observation? — Wayfarer

That's the beginning of a diagnosis of the problem. But it doesn't help much in trying to resolve it. Your realist question doesn't help either. Trying to describe objects "in themselves" apart from any observation is like trying to pick up a pen without touching it.

It is true, for instance, that several stars, when grouped together, make a constellation. But that is so because of something we humans do. It is not actually a feature of the natural world (using a common sense of what is natural). — J

This is a real problem. I don't know the answer and perhaps there isn't one - or not just one. In this case, we should compare constellations with another case. I suggest the solar system as being an actual feature of the world. ("natural" just makes additional complexity). These cases could also usefully be compared with the sun. My first instinct is to say that the solar system is maintained by a collection of what we call "laws of nature". The sun falls into the class of concepts of objects (medium-sized dry goods is not particularly helpful in this case, but indicates what I have in mind).

Second, how far can this be pushed? See Ted Sider's ideas about "objective structure." His "grue" and "bleen" people divide up the visual world in a bizarre way, yet everything they say about it is true. Sider argues, and I agree, that nonetheless they are missing something important about how the world really is. — J

I agree with you. My first stab at identifying what is missing is that this notion of truth is very thin. It is neither use nor ornament. It consequently doesn't have a future in our everyday language. I don't rule out the possibility of concepts like these finding a use somewhere some day. On the other hand, I'm a bit doubtful whether "how the world really is" is a useful or usable criterion for what we are trying to talk about.

I had a look at the article you linked to. It's very promising, so I've saved it. The concluding paragraph has a lot going for it.

The point of metaphysics is to discern the fundamental structure of the world. That requires choosing fundamental notions with which to describe the world. No one can avoid this choice. Other things being equal, it’s good to choose a set of fundamental notions that make previously unanswerable questions evaporate. There’s no denying that this is a point in favor of ontological deflationism. But no one other than a positivist can make all the hard questions evaporate. If nothing else, the choice of what notions are fundamental remains. There’s no detour around the entirety of fundamental metaphysics. — 'Ontological Realism' - Theodore Sider

The first task is to clarify the sense of "fundamental" in this context.

The irony enters when those, who generally take science to have only epistemic or epistemological, and not ontological, significance, then seek to use the results of quantum physics to support ontological claims, such as that consciousness really does, as opposed to merely seems to we observers to, collapse the wave function, and that consciousness or mind is thus ontologically fundamental. — Janus

That's a new one to me.

But a good metaphysician will recognize the category division, and the danger of contradiction if we allow that the actual is also possible. — Metaphysician Undercover

I'm sorry, but I don't understand what you mean by "the danger of contradiction". I'm used to contradictions existing or not - contradictions as a risk are new to me.

But I hope this is obviously not true. We can talk about what it would be like in Jindabyne, had it snowed, even though it did not. — Banno

Yes, it is obviously possible to discuss the consequences of a counterfactual. But "p is true" rules out "p is false"; or that p is incompatible with not-p. It seems natural to say that, in some circumstances, that there is no possibility that p is false - not that naturalness is the final court of appeal. So I think that this needs a little more clarification. Perhaps we need to say something like before the race is run, it is possible that my horse will win and possible that it will lose, but that after my horse has won, it was possible. Alternatively, we could explain a counterfactual as positing a context in which to consider various possibilities (I would have won my bet)