van Inwagen isn’t noted as an epistemologist, but he’s a modal skeptic. I thought I’d post the view, and see what people might have been working on in this area that I don’t know about.
The view is not about epistemic modals, but about modal claims of, as Plantinga puts it, the broadly logical sort. Most call this modality ‘metaphysical modality’. I can’t recall exactly the extent of vI’s skepticism, but for purposes here, I propose to talk only of metaphysical modals that are not logical modals. About these, vI holds, I believe, that we do not have the epistemic powers necessary for knowing the truth value of such claims.
There seem to be obvious counterexamples to this skepticism, however.
I know that nothing can be completely red and completely green all over, and I don’t think this is a logical truth (i.e., provable in the, or a, correct modal logic). Other cases are harder to assess. For example, take any counterfactual that is not a logical truth or falsehood. Then append a possibility operator to it. If the counterfactual is true, then the possibility claim is true as well. So take the false counterfactuals. The possibility claim will then be a metaphysical modal, but I think I know that many of these are true. For a specific case, consider the counterfactual “If Rhode Island were within the present boundaries of Texas, it would be a county instead of a state.” That’s not a true counterfactual, but it is metaphysically possible that it’s true, and I think I know that this is the case, but I’m less confident about the knowledge claim here than in the above case.
So I think vI’s position is not discriminating enough. I know Paul Tidman has written on this issue, but there must be other sources as well?