So you're claiming that potentials exist as something "independent" basically? — Terrapin Station

I think possible worlds exist independently of the actual world, yeah.

So is there a spatial location of your computer in the possible world you mentioned? — Terrapin Station

Yes, but only potentially as opposed to actually. It could have a physical instantiation but it doesn’t.

Ah - I see what you’re saying now. Well that’s fine, I don’t mind being in agreement with anyone on that point. But some nominalists such as Terrapin claim that abstract objects don’t exist in any sense, which I do disagree with.

An analogy that's entirely different than what we're analogizing? — Terrapin Station

I think you’ve misread my post.

In which case you are really in little disagreement with the nominalist: like you, they hold potentials are non-existent. — TheWillowOfDarkness

I don’t hold that potentials are non-existent. I hold that they exist in a sense analogical to the way actual things exist.

All the properties of a possible world would have to be non-physical.

Remember the problem was supposedly that possibilities had to exist, had to possess the univocal or equivocal sense of an actual state. — TheWillowOfDarkness

I haven’t said they need to exist in the sense univocal to something actual. My view is potentials have being, but in a sense analogical to the sense in which actuals have being: not in the same way, but not in an entirely different way.

but it has a serious consquence for our account of possible worlds: they cannot exist all (since existing things are actual). — TheWillowOfDarkness

This isn’t true if you accept the analogical use of language, in which case potentials have being in an analogical sense rather than in a way univocal or equivocal to the sense in which actual things have being.

You asked what properties non-material existents can have. On my view possible worlds are non-material existents and have properties in the way I described.

It seems to me a possible world where everything is identical apart from there isn’t a blue mug in front of me would have all the properties this world has minus the blue mug, but it would have them potentially rather than actually.

I'm not just assuming for no reason that possible worlds can't exist nonmaterially. It's via reasoning that we justify that they can't exist nonmaterially. — Terrapin Station

What is your reasoning that they can’t exist non-materially?

1.There are possibilities
2. They can’t be grounded nonmaterially in the nonphysical world
3. So they must be an upshot of material facts
4. If they’re upshots of material facts, they can’t exist in the nonphysical world but must exist in the physical world — Terrapin Station

Underlying the above is this:

the whole idea of nonphysical existents is incoherent. It's not worth bothering with. — Terrapin Station

You’re justification for believing possibilities are groundable materially is an assumed materialism. I’m not assuming the alternative (I actually think a fully cogent materialist world view would be really interesting), rather I’m reasoning in this case that possible worlds can’t exist materially, and so if they do exist it’s as abstract objects.

1. There are possibilities
2. They can’t be grounded materially in the physical world
3. So they must be abstract objects
4. If they’re abstract objects they can’t exist in the physical world but must exist in a mind or collection of minds
5. To remain possibilities in the absence of contingent minds they must exist within an absolutely necessary mind — AJJ

I don’t see at what point I beg the question.

So I suspect what you’d be doing there is begging the question, i.e. more circularity.

But I have actually shown them (in a non-circular fashion) to be groundable that way, in the divine intellect.

It isn’t actually a restatement. The premise is that possibilities can’t be grounded materially in the physical world, and the justification is that they haven’t (despite the opportunity offered) been shown to be groundable materially in the physical world.

Your 2 is that one can't describe the way that possibilities are grounded in the physical world, so if that's your justification for 2, that's circular. — Terrapin Station

I disagree. I’m not saying they can’t be grounded in the physical world by simply assuming they can’t; rather I’m offering you the chance to disprove the premise - if the justification was circular it wouldn’t be open to that disproof. If you were to offer one and I rejected it by simply assuming the premise then in that case it would be circular.

I mean to sum up my (adopted) explanation of things:

1. There are possibilities
2. They can’t be grounded materially in the physical world
3. So they must be abstract objects
4. If they’re abstract objects they can’t exist in the physical world but must exist in a mind or collection of minds
5. To remain possibilities in the absence of contingent minds they must exist within an absolutely necessary mind

Yours it seems to me is this:

1. There are possibilities
2. They can be grounded materially in the physical world

So the reason yours is circular and mine isn’t is our justifications for 2 in each case. I justify my 2 by showing that you seemingly can’t describe the way possibilities are grounded in the physical world, or that you do so simply by arguing in a circle. You justify your 2 by repeating your 1 (while assuming nominalism and materialism).

Of course, then we're just disagreeing on whether different things are logical necessities. You'd say your explanation is; I'd say my explanation is. — Terrapin Station

I’ve demonstrated mine is. Can you demonstrate your conclusion is a logical necessity (without arguing in a circle)?

If it’s a logical necessity that abstract objects obtain within the divine intellect then it isn’t circular. If possibilities conceived of as abstract objects remain possibilities in the absence of contingent minds, then they must exist within an absolutely necessary mind, one that can’t not exist. It seems to me that once you’ve reached a logical necessity you’re at the end of a straight line of reasoning.

It seems to me the circularity is avoided by the abstract objects existing necessarily within a Platonic third realm or the divine intellect. Obviously objections can be raised against both possibilities, but I don’t think circularity is one of them.

If abstract objects exist aside from "the divine intellect," and that's what we're talking about re possibilities being abstract objects, is that circular? — Terrapin Station

You’ll have to clearer yourself, I don’t know exactly what you’re saying there.

You wouldn't think that an explanation has to conclude that something can't depend on the present world, would you? — Terrapin Station

And I actually think I’ve been unfair to myself, since my explanation doesn’t conclude with what you say. The reason my explanation doesn’t wind up being circular is that abstract objects can be said to obtain within the divine intellect, which (if abstract objects exist) must exist necessarily unless abstract objects can be said to exist otherwise. Not an explanation you agree with obviously, but it doesn’t to my understanding wind up being circular.

If the explanation concludes "being concrete objects is what allows possible worlds to exist, since they CAN depend on the present world for that," why wouldn't that be an explanation just like yours, simply with a different conclusion? — Terrapin Station

Your claim that possible worlds can depend materially on the present world would have to be backed up in a non-circular fashion. And your explanation there isn’t a parallel to mine, which includes the claim that possible worlds can’t exist materially (which is valid so long as you remain unable to explain how possible worlds obtain materially).

So put simply the reason I reject your explanation as an explanation is its circularity, which isn’t something I think mine exhibits.

So when I say that possibilities are concrete facts, I'm not saying something additional about how they obtain? — Terrapin Station

You’ve not been saying that in answer to my question of how they obtain. You’ve been saying simply that they’re a consequence of the world not being strongly/causally deterministic, which as I’ve pointed out is circular.

So what seems to have happened is you said this:

Possibilities are real--they're the fact(s) that the world isn't strongly/causally deterministic. That doesn't hinge on thought, but it's not abstract, either. — Terrapin Station

Which is circular as well it seems, but it does say implicitly that possibilities are concrete (material) facts. So then I asked you this:

How on your terms do those possibilities obtain? — AJJ

And you started giving circular explanations for how possibilities obtain, when what I’ve wanted to know the whole time is how possible worlds such as one where this planet doesn’t exist can obtain as something concrete as opposed to something abstract.

So I made an error in my last post: What I’ve been saying that’s additional is not simply that possibilities are abstract objects, but that their being abstract objects is what allows possible worlds to exist since they can’t depend on the present world for that - it’s that last claim I’ve been trying to verify by asking you how on your terms possible worlds obtain (where the answers so far appear to be point-missing and circular).

I’m saying there are possibilities/possible worlds (ways things could have been) and that these are abstract objects (something additional about how they obtain).

But that's what I did. The world could be strongly deterministic. It's not. That's how (non-actual) possible worlds exist. — Terrapin Station

And I’m saying that amounts to a simple assertion that there are possibilities without saying anything additional about how precisely they obtain.

So your reasoning it seems is circular: possible worlds are explained by there being possibility which is explained by there being possible worlds. I’m saying that’s inadequate reasoning and so not a justification and so not an explanation as per the definitions I’ve quoted.

My justification gives an explantion for how the possible world obtains on my terms, i.e. I reason that being a consequence of a metaphysics that's not strongly(/causally) deterministic allows it to exist because on other terms it would not be able to. — Terrapin Station

You’re reasoning there is to the effect that possible worlds exist because possible worlds exist. I’m saying that’s not reasoning anything, rather it’s making an assertion that possible worlds exist and leaving it there.

It seems to me you can condense yours down to this: “There can be possible worlds because there are possible worlds.” — Terrapin Station

But you can’t because I’m saying something additional to that, i.e. I’m explaining how possible worlds exist (as abstract objects) and not simply asserting that they do without any enabling reason why they do/can.

So I reject your claim that you can make the same objection from your side.

So in short:

Mine: “Possible worlds exist on my terms by being abstract objects which allows them to exist where on other terms they can’t.”

Yours: “Possible worlds exist on my terms because they do.”

What did you do different than I did? — Terrapin Station

Here’s mine again: “There can be a possible world where this planet doesn’t exist [belief] because the possibility doesn’t depend on the material world from which we would not be able to derive that possibility [justification].”

My justification gives an explanation for how the possible world obtains on my terms, i.e. I reason that it’s being an abstract object which allows it to exist because on other terms it would not be able to.

It seems to me you can condense yours down to this: “There can be possible worlds because there are possible worlds.”

Here’s a parallel example to yours to press the point: “Unicorns can exist because there are unicorns.”

You’re not giving an explanation for how possible worlds can exist on your terms, just asserting that they do without offering that explanation of how I’ve been asking for.

As you could probably guess, I don't think that positing real abstracts is either right or reasonable. So should I say you're not offering an explanation? — Terrapin Station

You could, but that would be another assertion. I’m not asserting that you’re not providing a justification for the point under discussion - it seems to me I’ve demonstrated that.

Here’s the definition you get when you Google justification: “the action of showing something to be right or reasonable.”

You haven’t in my view shown yourself to be right or reasonable on that point - rather you’ve made an assertion that you haven’t yet backed up.

Here’s the second definition when I Google explanation: “a reason or justification given for an action or belief.”

So what your formulation amounts to structurally is: “There can be a possible world where this planet doesn’t exist [belief] because the possibility is a factor of the material world having possibilities [justification].”

Mine is the same structurally. The problem I have with yours is it doesn’t actually offer a proper justification, so what you’ve made there is an assertion rather than given an explanation.

What yours amounts to is: “There can be a possible world where this planet doesn’t exist because the possibility is a factor of the material world having possibilities.”

What mine amounts to is: “There can be a possible world where this planet doesn’t exist because the possibility doesn’t depend on the material world from which we would not be able to derive that possibility.”

That's just saying what a possibility is on your view. — Terrapin Station

I disagree - it’s taking an example of a possible world where this planet doesn’t exist and saying such a possibility can only exist if you’re a realist about possible worlds, i.e. it’s explaining how that possibility exists.

So "positing abstract objects called possible worlds" isn't another way of saying there are possibilities? — Terrapin Station

It is a way of saying that, sure - but it also explains how there are possibilities: There can be a possible world where this planet doesn’t exist because the possibility is an abstract object that exists independently of the material world.

You'd have to explain why on your view the fact that the world isn't strongly/causally deterministic isn't an explanation for how possibilities obtain. — Terrapin Station

Just to make this clear: Saying the world isn’t “strongly/causally deterministic” is to my mind just another way of saying there are possibilities. Saying there are possibilities doesn’t explain how there are possibilities. If you’re saying it’s simply a brute fact about the world that there are possibilities then fine - I don’t think that’s an adequate way to understand things, but we don’t need to argue about that.

Can I take it that what you’re positing is that the existence of possible worlds is some kind of brute fact?

What would be the explanation of rain that wouldn't be identical to the fact(s) that enable(s) rain? — Terrapin Station

Those would be identical. But saying “there is an explanation” about something (which I see what you’re doing as) isn’t the same as explaining it.

I explain possibilities by positing abstract objects called possible worlds, with this world being a manifestation of some of them.
— AJJ

On your view, isn't that the fact that makes possible worlds obtain? If so, how is that an explanation per your criteria? — Terrapin Station

It’s an explanation for how possibilities as you described them earlier obtain. All you’ve done it seems to me is describe possibilities without offering an equivalent explanation for how they obtain.