“For example, the modal non-rationalist (or, following Ayn Rand's naming conventions, irrationalist) thinks that there’s no deeper account of why zombies, ghosts, or inverted qualia scenarios are impossible.”
This is not, in fact, what all those who deny a freewheeling modal rationalism think. Many don’t.
O’Connail gives a pretty standard argument here for why the conceivability of zombies doesn’t show that they’re possible. ( https://link.springer.com/article/10.1007/s11098-021-01665-6 ). Why does his argument commit him to the view you ascribe to all mitigated modal skeptics?
I'll read the paper, but I'm dubious. What could the explanation lie in? It couldn't be something we can know a priori, nor could it be something we discover empirically. So what could it be?
The explanation could lie in something knowable a priori, but just not by us. (God might know modal truths that are beyond our ken, and might know it in a different way than the way he knows empirical truths. But human modal knowledge, the cool kids claim, is way, way more limited than that of an omniscient being. So even if the modal facts are knowable a priori, they just aren’t knowable in this way by us, at least if conceivability is the only tool in play.
Speaking of God, God is a nice toy example to motivate the mitigated modal skeptic’s position: the failure of the ontological argument, as well as the failure of the reverse ontological argument, shows us that there is at least one modal fact which - even if it could be known a priori by a more epistemically advanced being - can’t be known a priori. In the God case, conceivability is a dud. The mitigated modal skeptic’s (hella attractive) explanation of this is that God is far removed from day to day experience, and our modal knowledge doesn’t extend that far beyond the relatively humdrum.)
I agree the knowable a priori but not by us theory is possible--but then that's still an example of something being knowable a priori. On the topic of god, I don't think god is ideally conceivable, because god entails existing in all possible worlds, but we can conceive of a god that doesn't exist in all possible worlds. God is just as inconceivable as a necessary goat.
I agree with Premise 1 - I think it's incoherent to say that something is necessary while also saying that there's no reason it's true. I'm a bit apprehensive about the second premise because of Kripke's counterexamples. Before learning of them, I thought modal rationalism was self-evident, and after learning of them, I thought it was false, despite still believing that there must be a PSR for necessary truths. I'm still trying to figure out what I think of the objection given to Kripke's counterexamples. On the one hand, it seems like, "Water is H2O," is itself an proposition that is true in all possible worlds despite not being knowable a priori, and that that fact alone refutes modal rationalism. Which part of this does the objection attack? Is it not a proposition? Is it not necessary? Is it not knowable a priori? Are we conflating two different propositions, one of which is necessary and a priori and the other of which is contingent and a posteriori? Initially, I thought the meaning of, "Water is H2O," could be spelled out explicitly in terms of rigid designations in a way that shows it to be necessary and a posteriori, but it's not so simple - it seems that any way of spelling it out like this either makes it contingent or a priori.
I don't think the refutation of Kripke's counterexamples gives you much ground against a lot of the positions that modal rationalism supposedly refutes, though. Take the impossibility of zombies for example. This seems quite analogous to the impossibility of having water without H2O. It doesn't really matter why it's impossible. If it's impossible to have water without having H2O because, despite knowing fully what the word "water" means, there's still some further modal fact about it that we can't know a priori, then the same could be said of zombies. If it's impossible to have water without having H2O because that's just part of the meaning of the word "water," and we don't know this a priori, then the same could be true of zombies. So even if modal rationalism can be saved from Kripke's counterexamples, it doesn't seem to save certain applications of it.
“For example, the modal non-rationalist (or, following Ayn Rand's naming conventions, irrationalist) thinks that there’s no deeper account of why zombies, ghosts, or inverted qualia scenarios are impossible.”
This is not, in fact, what all those who deny a freewheeling modal rationalism think. Many don’t.
O’Connail gives a pretty standard argument here for why the conceivability of zombies doesn’t show that they’re possible. ( https://link.springer.com/article/10.1007/s11098-021-01665-6 ). Why does his argument commit him to the view you ascribe to all mitigated modal skeptics?
I'll read the paper, but I'm dubious. What could the explanation lie in? It couldn't be something we can know a priori, nor could it be something we discover empirically. So what could it be?
The explanation could lie in something knowable a priori, but just not by us. (God might know modal truths that are beyond our ken, and might know it in a different way than the way he knows empirical truths. But human modal knowledge, the cool kids claim, is way, way more limited than that of an omniscient being. So even if the modal facts are knowable a priori, they just aren’t knowable in this way by us, at least if conceivability is the only tool in play.
Speaking of God, God is a nice toy example to motivate the mitigated modal skeptic’s position: the failure of the ontological argument, as well as the failure of the reverse ontological argument, shows us that there is at least one modal fact which - even if it could be known a priori by a more epistemically advanced being - can’t be known a priori. In the God case, conceivability is a dud. The mitigated modal skeptic’s (hella attractive) explanation of this is that God is far removed from day to day experience, and our modal knowledge doesn’t extend that far beyond the relatively humdrum.)
I agree the knowable a priori but not by us theory is possible--but then that's still an example of something being knowable a priori. On the topic of god, I don't think god is ideally conceivable, because god entails existing in all possible worlds, but we can conceive of a god that doesn't exist in all possible worlds. God is just as inconceivable as a necessary goat.
I agree with Premise 1 - I think it's incoherent to say that something is necessary while also saying that there's no reason it's true. I'm a bit apprehensive about the second premise because of Kripke's counterexamples. Before learning of them, I thought modal rationalism was self-evident, and after learning of them, I thought it was false, despite still believing that there must be a PSR for necessary truths. I'm still trying to figure out what I think of the objection given to Kripke's counterexamples. On the one hand, it seems like, "Water is H2O," is itself an proposition that is true in all possible worlds despite not being knowable a priori, and that that fact alone refutes modal rationalism. Which part of this does the objection attack? Is it not a proposition? Is it not necessary? Is it not knowable a priori? Are we conflating two different propositions, one of which is necessary and a priori and the other of which is contingent and a posteriori? Initially, I thought the meaning of, "Water is H2O," could be spelled out explicitly in terms of rigid designations in a way that shows it to be necessary and a posteriori, but it's not so simple - it seems that any way of spelling it out like this either makes it contingent or a priori.
I don't think the refutation of Kripke's counterexamples gives you much ground against a lot of the positions that modal rationalism supposedly refutes, though. Take the impossibility of zombies for example. This seems quite analogous to the impossibility of having water without H2O. It doesn't really matter why it's impossible. If it's impossible to have water without having H2O because, despite knowing fully what the word "water" means, there's still some further modal fact about it that we can't know a priori, then the same could be said of zombies. If it's impossible to have water without having H2O because that's just part of the meaning of the word "water," and we don't know this a priori, then the same could be true of zombies. So even if modal rationalism can be saved from Kripke's counterexamples, it doesn't seem to save certain applications of it.