Seems to me that the history of 'civilization' has always treated those with disabilities as if they did not belong in the same places as 'normal' people. — creativesoul

I gave evidence earlier that this is not quite so; it's a relatively recent development, consequent on the development of the modern medical system.

I don't know how to reply to that. It's not clear to me where you want to go with what you have said.

Correspondence is not a deflationary theory of truth. Tarksi is compatible with any theory of truth worthy of consideration. Whether it counts as a deflationary theory is a subject of some considerable discussion, but Tarksi thought not.

I don't see how introducing yet another theory - truth makers - is illuminating.

Can we move on?

For the read-through, I think we are up to 2.2.3 Actuality and Actualism.

This thread was set up specifically to work through the two articles. Look:

This thread is for a read through of two SEP articles on possibility and actuality. — frank

I've said previously that before we embark on a critique of the implications of possible world semantics, we need both a strong grasp of modal logic and an understanding of the main theories concerning its application. That's what I have been doing. I don't think what you have said demonstrates such a grasp on your part.

Again, it seems to me that what you are doing is attempting to critique modal theory, which is based on semantic theories of truth, by replacing that basis with a correspondence theory. It's no surprise that this doesn't work.

I'm more than happy to consider the consequences of possible world semantics. Indeed, with others here, we have been doing just that. But not by first misunderstanding it.

Are you a proponent of virtue ethics? — Jeremy Murray

Sometimes. Ethics is not algorithmic.

Hard to figure out what you're talking about. — AmadeusD

Well, yes - you'd have to change your mind... :wink:

Wouldn't it benefit your organisation to find out why it hasn't attracted anyone, over the last twenty years, who needed an accessible toilet? There's a large part of the population that you are not accessing.

This definition is neutral in terms of the social and medical model. — bert1

It is a classic, straight-forward example of the Medical Model.

The Equality Act definition makes disability depend on "an impairment (physical or mental)", and
the "effects of that impairment on the person’s abilities". It sets up disability as something that is wrong with the person. And is "normal day-to-day activities" is explicitly normative, treating deviation from that baseline as a deficit in the individual. As so often, the law adopts a medical model for pragmatic reasons.

That's not just my view. A quick search will find Parliamentary enquiries and academic papers pointing to this issue.

The social model sees disability as when society’s structures, attitudes, and practices create barriers that prevent folk from fully participating in social, economic, and cultural life, regardless of their physical or mental differences. Disability is not caused by the person’s impairment, but by the mismatch between the person and the environment.

The capabilities model sees a person as disabled to the extent that they are unable to achieve or exercise the essential capabilities necessary for living a life they value, due to a combination of personal, social, and environmental factors. Disability is understood not solely as an impairment, but as a constraint on the real opportunities (“capabilities”) available to the person.

If a fish jumps out of the water and land on the path and starts exhibiting challenging behaviour, the medical model would have us fit it with artificial lungs and a trolley at great taxpayer expense. Proponents of the social model will pop it back in the water where it is not disabled. — bert1

Yep.

As usual. you reject my arguments because they are inconsistent with what you believe, without even addressing the the truth or falsity of the premises, or the validity of the argument. — Metaphysician Undercover

Nuh. I reject your arguments because they are muddled.

Take:

Possibilities are infinite, so we cannot have "the set of all possible worlds", as required for the truth conditions. That is impossible because any proposed set will be incomplete. We will never have the true actual world (M), therefore the stated truth conditions for possible worlds semantics are necessarily violated, truth cannot be obtained. — Metaphysician Undercover

It contains at least a half-dozen compounding errors. There are infinite sets, and indeed uncountably infinite sets; and we can give truth conditions for those sets. Consider ℕ and ℝ. These sets are not "incomplete" - you trade on an ambiguity here. M is not the actual world, as you think, but an interpretation of a modal system. A model M is an ordered structure ⟨W, R, V⟩, and the actual world is a distinguished element w∈W. Kripke prooved that K, T, S4, and S5 are both complete and consistent, so truth can be "obtained" (your term) for those systems.

You are still looking for epistemic truth in a semantic system.

You haven't followed what is going on in the SEP articles.

I was referring to a correspondence theory of truth. — Relativist

Indeed, but very clearly what is being used in modal logic is a semantic theory of truth.

...you've been referring to indexicality, which is beyond Tarski. — Relativist

Well, we can use Kaplan's account, if you like. It's an extension of the semantic theory of truth that does deal with indexicals.

This actually does apply to correspondence theory, which is deflationary. Deflationary theories are based on the equivalence principle: — Relativist

Nuh. It's not deflationary. It's very much one of the substantive theories of truth.

The core problem with what you are saying seems to be that you are trying to use the correspondence theory in the place of the semantic theory, and bumping up against the problems this causes.

, , keep in mind that a rigid designator only refers to an individual in those possible worlds in which that individual exists.

If Homer didn't exist, then "Homer" doesn't refer to anyone.

Yep. Bullshit.

The question of what establishes the truth of a statement then depends on which definition of truth is being used. — RussellA

And the one being used in the article is Tarski’s Truth Definition.

I brought the topic up, in my innocence. — Ludwig V

It's good - it brought out another aspect into my response to the article. The SEP article presumes maximally complete worlds, but the logical work these theories are actually used for does not require maximality.

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.

So....treating it as a possible world, even though it's not possible. — Relativist

What, exactly, is not possible?

Doing what you suggest is inconsistent with correspondence theory of truth - the Frodo statement is not "true" under this theory. — Relativist

Have you an argument to go along with that? And what of it - we are using Tarski's semantics, not correspondence.

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....

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

Yep, and we need not be referring anybody or anything at all for it to be meaningful, as Wittgenstein said we must not confound the meaning of a name with the bearer of the name. — Richard B

The word "learning" is problematic. It'd be better to say "the causal chain is a chain of people using the name to refer to Aristotle correctly.

“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.

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. — Ludwig V

Yep.

...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. — Ludwig V

Yes, I think so. The point - lost on some - is that the logic is much the same.

What about stories that mix real and fictional characters and/or places? — Ludwig V

That'd just make yet another possible world, with some characters in common with our own...?

I, on the other hand, don't know what I'm talking about. — Ludwig V

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.

Maybe have a read of section X of Donnellan's Proper Names and Identifying Descriptions - the Thales example.

Yep.

Jamal was very generous with giving Bob enough rope. The result was inevitable.

While what you say is mostly correct, his views were in the end small and nasty.

1. What you learnt about Aristotle enables you to refer to Aristotle - to use the tag. — Ludwig V

No!

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.

(Remember - what preserves the causal chain is people using the tag.) — Ludwig V

Yes! And that alone!

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.

So its not "What you learnt about Aristotle enables you to refer to Aristotle"!

the inferences are all qualified by, "within Tolkien's fictional world...". — Relativist

Yep - treating it as a possible world, and truth as true-in-a-world.

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

"unqualified" is problematic; we can take this world, the one we are in, to be w₀ and then define truth simpliciter as true-in-w₀. And note thatin w₀ it is true that in Tolkien's world Frodo is a hobbit...

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

Yes. 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.

Fun, isn't it?

I don't think so, but I'm not sure...

The idea is somewhat ill-formed, but it's related to the idea that some differences make no difference. I need to think on it some more.

As I've shown... — Metaphysician Undercover

You pretend your already repudiated arguments were adequate. They are not.

If Determinism is true, there can only be one actual world, meaning that there cannot be possible worlds. — RussellA

This rather depends on how one understands "determinism".

Determinism is a thesis about law-governed evolution within a world, not about the space of logically or metaphysically possible worlds. Even a perfectly deterministic world can be one among many possible worlds, perhaps differing in their initial conditions. Determinism only blocks alternative futures for this world, not alternative worlds altogether.

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. — Ludwig V

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

The idea that there may not be One True Account of reference seems very plausible to me. — Ludwig V

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.

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.

We have never, in over 20 years (i've not been here the entire time) required one for any disabled person. — AmadeusD

Given that one in six folk have a disability, your organisation might do well to reconsider it's clientele and hiring strategy. Or is your accessible toilet at the top of the stairs?

But here's the reason your contributions are unproductive: they express personal opinions and anecdotes.

The three most common impairment types New Zealanders experienced were mobility (13 percent), hearing (9 percent) and agility (7 percent). — Appendix: disabled people population and life outcome statistics

While what you say might be so, it remains that the common thread in Bob's justification of racism, homophobia and transphobia was a form essentialism that he took to derive from Aristotle and Aquinas. None of that rescues Bob’s position, because the problem is not essentialism simpliciter, it is the specific way essentialism is being used.

His essentialism was unfalsifiable by design. Counterexamples were dismissed as “pathological,” “deformed,” or “non-natural,” while conformity were treated as confirmation. That is not an epistemology; it is an immunisation strategy. An essence that cannot be contradicted by any actual instance is doing no explanatory work.

His appeal to Aristotle and Aquinas was selective and anachronistic. Neither thinker held that every natural tendency grounds a fixed social role, nor that deviation implies defect in a moral sense. Aquinas in particular is careful to separate natural inclination from law and from virtue. Bob reads later ideological commitments back into scholastic metaphysics.

Tim is correct that racism is not wrong because race is unreal, and that essentialism alone is not the issue. But it remains true that Bob’s justifications for racism, homophobia, and transphobia rely on a misguided essentialism that illegitimately converts descriptive generalisations into normative constraints while insulating itself from criticism.

As you wish.

"there is a possible world in which Hobbits, Trolls and Orcs exist" — Relativist

A thing exists if it is in the domain of a world. That is, if it can be used in an existential quantification. Existence is what the existential quantifier expresses. Things can exist in one world and not in another. One point of difference between Lewis and Kripke is that for Lewis things exist only within a world, while for Kripke the very same thing can exist in multiple worlds. — Banno

On the account given here we make sense of existence within worlds. Frodo is a Hobbit - h(a). By existential generalisation there is something that is a hobbit - ∃(x)(h(x) - which can be read as "something is a hobbit" or as "hobbits exist".

There is a world w whose domain contains at least one object satisfying each of the predicates hobbit, troll, and orc.

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.

The question I have then is about the scope of possible worlds, and what exactly their metaphysical claim is to reality. — QuixoticAgnostic

The logic itself is (almost) metaphysically neutral. The concrete approach is one interpretation among many. And the answers to your questions will depend on what approach is adopted. Alien Properties are intriguing, but the response will very much depend on what else one accepts. It's not difficult so much as complex.

Impossible worlds. Have a look, but we might here stick to the present article.

You are babbling. Kripke showed how give truth conditions for modal claims using Tarski's semantics.

See the Island Universe for a related reflection.

Yep.

This thread reeks of Americans being surprised that their values are not universal.

All I mean by "meta-world" is, basically, some world where all possible worlds exists. Based on the definitions given wrt AW1, that seems impossible, because possible worlds exist maximally, and a "meta-world" would connect possible worlds, hence not maximal, hence a contradiction. — QuixoticAgnostic

Yep. Nice.

And does that not introduce a conflict with how we describe existence? — QuixoticAgnostic

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.

An interesting point, though.

@frank

One last word on intensionality for Abstractionism, concerning that paragraph about methodology.

We saw earlier how speaking roughly, the intension of π is the rule that tells you what π’s truth-value would be in every possible world. At issue now is, which is to be master?

The concretist starts with worlds as given (from AW1) and treats intensions as derivative: once we have worlds, an intension is just a way of tracking truth across them.

The abstractionist reverses the order. Intensionality, understood as truth-at-a-world, is taken as basic, and possible worlds are introduced as whatever is needed to make sense of modal variation.

My own intuition is that the disagreement is not about whether worlds or intensions exist; it’s about which we take as explanatorily primary. Seen this way, the two positions, concrete and abstract, are complementary rather than contradictory: they are different “perspectives” on the same metaphysical landscape. That it's more a difference about how we say it than about what is being said.

@frank, it's clear and got lost somewhere. I'm not going back for Meta, who will double down and object to whatever is suggested. Relativist might catch up.

So I think we move on?

but how are they absolutely separate? — Metaphysician Undercover

Again, that's explained in AW1.

But you claim to have read and understood that... :roll:

How can you expect to be taken seriously?

What would make such a world POSSIBLE? IOW, how do you account for its existence? — Relativist

AW1 w is a possible world =def w is a maximal connected object. — SEP

I'd sugest you go back and read that section.

I think you're alluding to modal logic as a formal system. — Relativist

No allusion. I was quite specific.

One can utilize the formal system to go through the mechanics of the logic, without committing to possibilism/actualism much less necessitarianism/contingentarianism. — Relativist

Yep. I've pointed this out, several times. see for example

Filling out that last point, Kripke and Lewis give different ontological readings of the same formal machinery. Their logic is the same, but the metaphysical story differs.

Kripke (Naming and Necessity):
Proper names refer rigidly to the same individual across worlds.
Necessity is primitive and tied to rigid designation.
Modality is not reduced to something non-modal; it is taken as metaphysically basic.


Lewis (Modal Realism / counterpart theory):
Worlds are concrete; individuals do not literally exist in more than one world.
Identity across worlds is determined via counterpart relations.
Modality is reduced to quantification over concrete worlds.

Shared Logic / Semantics
Possible worlds semantics: Both use worlds as the basis for evaluating modal statements.
Quantified modal logic: Both accept first-order quantification over individuals.
Transworld reference: Both presuppose a way to interpret identity or counterparts across worlds.
Truth-at-a-world: Both define modal truth in terms of what holds at particular worlds.
Accessibility relations: Both can accommodate structured relations between worlds (for temporal or metaphysical distinctions).
Formal rigour: Both agree that modal claims can be modelled systematically, independent of metaphysical interpretation.

Summarised by ChatGPT — Banno

Yep.

This cannot be correct. If each possible world is separate from every other, in an absolute sense, then there would be no point to considering them, as they'd be completely irrelevant. — Metaphysician Undercover

You'd think the penny had dropped... but:

So, it's kind of clear that you aren't reading along. Can you remedy that? — frank

Yep. And

If there is no causal connection sometime in history, in what sense are they possible? — Relativist

Fucksake.

How does Kripke get around a name being a rigid designator when it is not known that in a causal chain one event necessarily follows another. For example, being a rigid designator would require there was a necessary connection between two events. — RussellA

Kripke did not fill out his theory of reference. Never did.

It was offered only as an example of how references might be fixed apart from a definite description. At the time his audience would have bee somewhat incredulous; this kid (he was a teenager when he published the first few articles) saying that Russell's logic was wrong.

So he suggested a possible (!) alternative, more as a rhetorical tool than a tight bit piece of argument.

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.