Metaphysics Of Modality

Front 1

What are the two classes of fictions in Armstrong's 1989 modal fictionalist account?

Back 1

Two step fictionalism—there is a great fiction which asserts the existence of a bunch of little fictions. The idea of the two step fictionalism is supposed to be, according to the great fiction, that at each world it is true that it is the only actual world but according to the little fiction at that world, there are other worlds.

Front 2

Contrast strong and timid modal fictionalisms

Back 2

The difference comes down to how you answer the question: Is the fiction supposed to provide an explanation of the applicability of the modal vocabulary?
• According to strong views, the answer is yes. Gideon and Armstrong go this way.
• Acccording to timid views, the answer is no. Hartry and Ted (in the Ersatz Pluriverse paper) go this way

Front 3

Give a problem with strong version of modal fictionalism.

Back 3

You can't state the view using any modal terms since you're claiming that the fiction is actually explaining the applicability of those terms. Gideon points out that this is going to be hard to do because the `according to' locution is itself modal.

Front 4

What is the Brock-Rosen objection to modal fictionalism?

Back 4

Problem arises when we consider modal status of certain claims about possible worlds. Consider the biconditionals that the modal fictionalist employs and ask: are those biconditionals necessarily true? Well, yes, because according to the modal fiction, at every world there are many possible worlds. So then it's true that there are necessarily many possible worlds. But then it has to be actually true that there are many possible worlds.

Front 5

What is Hale's Dilemma for modal fictionalism?

Back 5

Gideon thinks that the fictions aren’t literally true. So now he has a dilemma on his hands, are the fictions necessarily or contingently false?
• If they’re necessarily false, you can’t nontrivially say ‘If it had been the case that the possible worlds fiction was true then . . . ’ because this is going to have a necessarily false antecedent. So every conditional of that form would be true, not just the conditionals which comport to some degree with our normal linguistic practice
• If they’re contingently false, then the fiction could have been literally true!

Front 6

What is the incompleteness objection to modal fictionalism?

Back 6

Consider some proposition who’s modal status is unknown to us. If you’re a modal fictionalist it’s not just that it’s modal status is unknown, but downright there is no matter of fact about its modal status. Lewis makes a similar objection to sparse linguistic ersatzism.