iwpoe wrote:

Well, I'm trying to think of a case of something that is both a potency but can also be said to not exist, which does go back to his question. I understood Feser to gloss potencies as things which exist qua capacity to become actual. (SM p 33 par 1) The flatness of a ball that is now round "is not nothing".

I see.

When a potency is actualized, it doesn't go from non-being to being. It goes from one kind of being, being-in-potency, to another kind of being, being-in-act. Everything that has being exists. So, potencies exist. So, there are no cases of potencies that do not exist. 

iwpoe wrote:

So, I'm trying to think of what Daniel could possibly mean to speak of when he asks "After all how can a non-existent being stand in potency to anything?" What is something that might exist that doesn't stand in potency of anything? "Unicorns" and "square-circles" are standard things that are said to not exist, though in different ways, so I tried them out and hoped they would be clarifactory.

“Things” that don't exist can't stand in potency to anything, because they don't exist. We're not referring to anything when we write “Things that don't exist”. The term is vacuous, having no referent. It's meaningful, but vacuous.

edit: I misread this:

iwpoe wrote:

What is something that might exist that doesn't stand in potency of anything?

Sorry about that. Late night. I see Daniel's already replied, so I'll leave it there. Dinosaurs are another example.
 

Etzelnik wrote:

John West wrote:

I would also point out, in case you're a classical theist, that given creatio ex nihilo and God as pure being-in-act, it follows that there must have been metaphysical possibilities preceding potencies. If you're not a classical theist, then, of course, this kind of argument is likely unconvincing.

 
You mean ontologically? Or even temporally?

I mean that metaphysical possibility is ontologically prior or more basic than potency such that there are metaphysical possibilities that have nothing to do with potency, but no potencies that have nothing to do with metaphysical possibility.

I didn't have temporal priority in mind. Not too sure about temporal priority.

truthseeker wrote:

I would say that it's practically impossible for the ice cube to be melted relative to the circumstances, but metaphysically possible for the ice cube to be melted.

Well, okay. But on the supposition it's declared by divine fiat that the ice cube won't melt, then since God is radically immutable—and therefore cannot change his mind—it's impossible for the ice cube to be melted. It's a metaphysical stipulation[1], following from Divine Omnipotence and Divine Immutability. If you want to argue about metaphysical principles, then we can but the impossibility follows cleanly from metaphysical principles.

The talk of relativity to circumstances itself implies a non-potency-based notion of metaphysical possibility. In fact, it sounds a lot like implicit possible worlds talk.

[1]On a Lewisian scheme, it follows from the principle of recombination. In fact, on most extant modal metaphysics, the example works.

edit:

truthseeker wrote:

Then I understand 'x has a potency to be F' as 'x is not F and it is metaphysically possible for x to be F.' Would you agree that x has a potency to be F iff x is not F and it is metaphysically possible for x to be F, given my definition of metaphysical possibility?

I'm not sure I would say that "x is not F and it is metaphysically possible for x to be F." fully captures everything there is to say about potency, but if I understand your "x is not F" correctly as "F is not in-act for x" then I would say that iff your conjunction holds, "x has a potency to be F". Yes.

truthseeker wrote:

Could you give an example of an x satisfying the following propositions?

1. It is metaphysically possible for x to be F.
2. x has no potency for being F (or what I take to be equivalent formulations, x isn't potentially F, x isn't F in potentia, etc.). 

Actually, there is an easier way to demonstrate. The distinction between possibility and potency comes up lots with counterfactuals. To wheel out my stock example, consider an ice cube on some planet no living entity will ever go near. The ice cube has the potentiality to be melted, but it's declared by divine fiat that the ice cube will never be melted – space is dead, and cold, so the ice cube will never be in circumstances where it would melt. So, it's impossible for the ice cube to be melted even though it has the potentiality to be melted. But this implies that possibility and potentiality are distinct, and that possibility therefore cannot be completely analyzed in terms of potentiality.

One might respond that God could have created the world such that a solar flare melts the ice cube, or something. But that just admits distinct modal notions like possible worlds, or at least notions of possibility wherein P is possible iff P does not conflict with the Divine Nature. It says God could have brought about a different possible world where He did not declare such a fiat, or at least that it would not have been against His Nature to do so.


-----
A couple elaborations:

[1] It's the same style of argument with the negation symbol moved around: 

1. It is metaphysically not possible for x to be F.
2. x has a potency for being F. 

Incidentally, since x would otherwise require a substantial change and therefore—on scholasticism at least—a change in identity, the statement “It is metaphysically possible for x to be F only if x has a p

DanielCC wrote:

I am wondering what would be the best way to tactfully advertise these boards - I think there's most definitely niche for this type of site in Philosophy of Religion circles; a way to set up a sort of dialogue with all those WLC fan-bloggers (that's meant with no disrespect) out here.

What I saw Jeremy do yesterday was tasteful. Usually there is a function that lets you turn your username into a link. If you link your name to this forum and provide good, clear, cogent arguments (at philosophy of religion blogs you already read I mean), then that advertises better for this forum than bopping around dropping links like some internetized used car salesman ever could. In fact, it's the only thing I've seen that I consider even a little tasteful.