Well, I don't know if PSR implies "everything has an explanation" as that sounds like it could regress. The first principles actually ground explanation and are a source and cause of them, which is why they and PSR seem absolutely necessary if we are going to have any real and sure understanding of things whatsoever.

The more I've considered it, the more I've wondered about Feser's point to Arif in their debate regarding responses to the argument begging the question.

I think your first response after the ad hoc problem is interesting. They must, as you say, offer some principled reason for assuming their faculties have sufficient reasons, while rejecting it for other domains. But, in drawing the distinction, which presumably must be justified in accord with principles of rationality, aren't they going to be presupposing their cognitive faculties are properly functioning, and therefore presupposing PSR holds for their faculties? If so, it seems like this wouldn't really be an option for them to take in explaining how they can be justified in assuming their faculties have sufficient reasons given the supposition that there really are brute facts.

I'm not sure if that's precisely the direction you wanted to take it, but it seems there could be difficulties in attempting to formulate the distinction while avoiding a kind of circularity.

Not from what I saw. I think one line of response to the notion the argument is parallel to the evil demon scenario is drawing a distinction between logical and epistemic possibility. The logical possibility that there is a demon deceiving me clearly isn't enough to undermine trust in our faculties. But, assuming PSR to be false, it's not merely a logical possibility that our faculties are without reasons, but it's an epistemic possibility, i.e. we have some reason to think it could really be occurring, and therefore would need some justification for holding it isn't happening, which, I think, raises the problems of circularity.

That is to say, a different way to argue for PSR in a retorsion argument would be to say that if my inference that "Socrates is mortal" regresses in an explanatory chain ("Because Socrates is a man and I know that", "Every man is mortal and I know that", "Because men are material and material beings decompose, and because we observe that all men die", "because we have seen such and such and because XYZ" etc) that may culminate in a contingent brute fact ("because... No explanation!"), then the whole inference is logically compromised. And since our inferences ultimately trace back to extremely long series of contingent facts in reality, we cannot open the door for "a little bruteness" in reality without compromising the intelligibility of our inferences and reasoning processes.

What do you think?

RomanJoe wrote:

There were two discussions in two different comboxes. I originally sided with Tyler's objection to Feser. I'm not sure I do anymore though. Basically he was arguing that Feser is making an argument from epistemic possibility. That is, if it's possible that your cognitive faculties are unreliable then this entails radical skepticism concerning said faculties. Or, in Feser's words, if it's even possible that your cognitive faculties are victim to brute facts, then you cannot trust their deliverances at all. Tyler was claiming that radical skepticism concerning our cognitive faculties does not follow from the mere possibility that they may be unreliable. He used the evil demon scenario to make his point. Tough such a scenario is possible, we don't think this entails radical skepticism. Therefore, epistemic possibility concerning the undermining of our cognitive faculties does not necessitate radical skepticism concerning their deliverances.

Tyler frequently made the case that there is a parity between the evil demon case and the brute fact case, insofar as on both scenarios there's the possibility that our cognitive faculties are unreliable. Therefore, if we don't think the former necessitates radical skepticism then we shouldn't think the latter does.

Mr. Green made some good counter points to Tyler. One of them was that brute facts wouldn't just undermine our cognitive faculties they would make them completely irrational. In the evil demon case if the demon causes you to go blank every time you try to come to the conclusion of a syllogism (All men are mortal...) he is not undermining the fact that from the two premises "Socrates is mortal" does follow. With brute facts, it would actually be the case that from those two premises "Dogs are books" may follow from the preceding two premises. It's not that you are following a logical process that is just halted or thwarted, it's that your logical process may ACTUALLY yield irrelevant conclusions given a brute fact scenario.

The evil demon can't change the fact that "Socrates is mortal" follows from "All men are mortal; Socrates is a man," no matter how much he screws around with your mind. And it would still be the case that you would come to the proper conclusion if the demon wasn't messing with you. However, with brute facts those two premises may lead to irrelevant conclusions, they would make it the case that there is no necessary connection at all between "Socrates is mortal" and "All men are mortal; Socrates is a man." In fact there would be no necessary connection between any premises and their conclusions.

 
Another response, which I pointed out durig discussion back then, is that common solutions to the demon scenario are not available to the PSR one. In particular, something that I think a lot of people miss when discussing this retorsion argument, but is actually explicitly explained by Koons, Pruss and Feser, is how if we're doubting PSR then we can't even say the skeptical scenario is *improbable*, because objective probabilities attach to objects and their dispositions and patterns, but of course that assumes intelligibility. So common replies to the evil demon scenario are not available here. We can't actually say that it is improbable that we're prey to the skeptical scenario. We can't use abductive arguments here either (as is often done with the demon scenario to argue that the demonless one is simpler etc etc) without somehow accepting PSR (which *is* the best explanation). We also can't use basic beliefs to move away from the problem, as what would these basic beliefs be, if not basic beliefs in the intelligibility of reality?

The problem is that the PSR denier is denying the very principle that would allow him to get out of the skeptical scenario. It is a lot different from the situation of someone postulating another *potential explanation* for the observed facts, which is what is done with Descartes's demon, brain in a vat, etc. The suggestion that there may not be any explanation whatsoever is very different from the suggestion of different competing (even though bizarre) explanations for the same facts. I don't think anyone can get out of a skeptical scenario without accepting some form of intelligibility, because that's the very issue at hand -- but then the only alternative would be for the PSR denier to limit such intelligibility in a principled way that doesn't imply PSR. How one can do that without proposing something ad hoc or facing the problems I mentioned, I don't know.