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)

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

Take a weather map, a geological map and a road map of the same territory. They are not competitors, and they describe different aspects of the world. The question of which is the most accurate doesn't apply. They are all about truth, but not about the same truth. The question which is the best map depends on the context - what you are doing, what your interests are.
Some puzzle pictures can be taken in more than one way. Again, those questions don't arise - the interpretations are not in competition with each other.
The territory and the picture are such that they can be represented in more than one way. That's the reality. There's no way to make a choice.
On the other hand, I'm not at all sure that the "interpretations" model applies to this debate. Some form of realism seems to me much more satisfying than anti-realism or idealism. The latter seems to be make far too much of our limitations and failing to recognize that our senses and our language are very powerful tools.

Yes, quite so. Two my eyes, this debate looks like a microcosm for idealism vs realism. But with a difference, that in some sense it is for real. But then I ask myself How is that possible unless reality and our ideas are really in conflict? We have come up with some new ideas - wavicles, entanglement, etc - and no doubt more will be required.

I may be making myself misunderstood. The error I mean is to treat the "observer" as in a separate world from the "observed." They're not one and the same, though. — Ciceronianus

It's quite simple really. From one point of view, the teams on the field are separate entities; from another, they are a unity - together, they are a fight, or a match. (From a third point of view, each team is made up of 11 individuals.) Each pair of shoes is a unity of two individual shoes. I don't see a problem here.

"things, as phenomena, determine space; that is to say, they render it possible that, of all the possible predicates of space (size and relation), certain may belong to reality" (CPR). — SophistiCat

I agree with most of that. I can see that we need to say that the actual is possible - even if that is a bit awkward in some ways. It certainly beats saying that the actual is not possible.
I'm not sure I understand this sentence. But if you mean that things determine space, rather than the other way round, I'm with you.

But Banno seems to be influenced by some sort of common language intuition which makes him think that it's nonsense to say that what is actual is not possible. — Metaphysician Undercover

There's a false dilemma there. There's something wrong with saying that the actual world is possible and something wrong with saying that it is not possible. I am trying to express that by saying that the actual world is not merely possible and that it is different from all the other possible worlds in that respect.

What you propose here is just ridiculous, because one could just as easily stipulate that the world which Branson's wife did not die, is the actual world. — Metaphysician Undercover

You are missing the point. You cannot stipulate which possible world is actual. That's not a decision that we can make. We can only recognize the status of the actual world.

That was behind his legendary remark 'does the moon continue to exist when nobody is looking?' I think the rhetorical import was 'Of course it does!" — Wayfarer

No doubt about that. But one needs more than that to refute the opposition, which will repeat its mantra "Give me evidence" - and of course that requires looking and not looking at the same time. So the standing of that response is not just that of a straightforward assertion. The interpretation of the language here needs to be laid out in a different dimension.

This is why we have ontologies like model-dependent realism, which the adherents recognize is not consistent with traditional realism, but they give it that name anyway, to create the illusion of consistency. — Metaphysician Undercover

Why would anyone want to create an illusion of consistency? Most often, it seems to be the primary aim of philosophy to puncture illusions.

You are stipulating that there is an actual world, which is not stipulated, but is already there. — Metaphysician Undercover

I don't know about modal logic. But I understand the concept of a possibility as inherently allowing that there is something that would count as its realization. It is possible that it will rain tomorrow is incomprehensible unless there are circumstances in which it is raining and others in which it is not. In the context of probability we call this requirement an outcome. It refers to the result of the coin toss or whatever. When we formulate a possibility we are stipulating the circumstances in which the stipulated possibility will be realized, but not whether they obtain or not. Actuality is what realizes some possibilities and kicks others into touch. If there were not such things, both probability and possibility become meaningless.

But for the rest of us, the actual world is considered to be one of the possible worlds. — Banno

That seems to me a bit confusing, because it suggests that the actual world is merely a possible world. Surely one needs to say something to the effect that the actual world is different from all the possible worlds. Compare the difference between an image on a screen, which gives us a possibility, and the actual/real scene, which is in a different category. Perhaps the point is that an image is always an image of something. What is actual is that something.

Definitely. It's taken me a while to realise that its required to claim antirealism. It makes me very uncomfortable as I need to push back hard on the likes on Banno claiming that perception is direct. — AmadeusD

It seems to me that "direct" and "indirect" do not have a determinate application in the context of perception. So it's like "glass half full" and "glass half-empty". Which means one should not draw dramatic conclusions from either.
But do we think that noise-cancelling headphones prevent us from hearing what's going on, or do we think that they enable us to hear what is going on?
Do they distort reality? In one sense yes, in another sense no.

This thread provides good evidence that you need to put your money down on specific definitions or you’ll never\\ be able to discuss beyond just the surface of metaphysics. If we come back in a month and have the same discussion, the same arguments will just get recycled over and over without ever having a resolution. If you want to go deeper, you have to commit. — T Clark

I agree that one has to pay attention to the ways that words are used - the concepts that define the discussion. But I do not agree that laying down a definition at the start avoids the issues - though I do not deny that it may sometimes be helpful.
But no definition (rule) can cater for all future possibilities - there can always be cases where interpretations of the rule differ. There's no reason why these can't be sorted out, but they can only be sorted out when they appear; they cannot be sorted out in advance.
This is all particularly tricky in philosophy, because disagreements so often turn on different uses of words - different presuppositions.

We can write "Kp" for "we know p", and "◇Kp" for "we might know p", and "~Kp" for "we don't know p" and "~◇Kp" for "we can't know p", none of which are tensed. — Banno

W can write "Kp" for whatever we like. Once we have interpreted it, however, (I think that's the right word), there are consequences.

"we know p", is compatible (awkwardly) with "we might know p". But it is incompatible with "we don't know p" and "we can't know p".
"we might know p" compatible with "we know p" and "we don't know p"; it is incompatible with "we can't know p",

In other words, we can interpret "Kp" however we like, but that does not mean we can substitute any interpretation for any other. "We know that p" and "We might know that p" are not inter-substitutable.

In addition, we have the issue of tensed or tenseless. This is complicated and doubly complicated in this context, because we have two verbs involved. But I'm stuck on "it is raining" does not follow from "It might be raining".

I might well be confused about what tensed and untensed truths.

I think the biggest argument for antirealism is the actual facts of eyes, ears, noses and mouths (and skin, I guess). I do, however, think its possible I've not come across a name for the position I actually think its reasonable, because its not idealism as antirealism might suggest.
I suggest antirealism about perception is roughly, unavoidable, but that antirealism as a metaphysical comment seems... tenuous as best, and seemingly ridiculous at worst. Maybe that clears up where I'm not understanding the issues in the previous comments. — AmadeusD

I agree with you that we're not all that far apart. There is a truth in anti-realism; where I disagree with it is the inflation of that truth into a Grand Doctrine. In the case of perception, it is inescapable true that what we know about the world around us comes to us from our senses.
But it is what the anti-realist (idealist) makes of this mundane fact that bothers me.
The point of the discussion in that post is the idea that our perceptions (or language) are not self-contained but point beyond themselves to a mind-independent reality, which can be known by us. Which does not mean that we will ever know everything about everything, so that there are always some things that are not known.