Callum:

I've considered the point regarding inscrutable probabilities and I don't think it has any bite against PC either. Even on the strongest reading, all it implies is that there's no way we can make an objective probability judgment regarding our cognitions having explanations. But from that fact it simply does not follow that either (a) we have evidence that our beliefs don't have explanations; and / or (b) we have evidence the relevant appearance was the result of faulty information.

Last edited by UGADawg (7/31/2017 11:37 pm)

He doesn't have to have a reason to think the appearances are reliable, though. All that's required is the absence of compelling evidence that they are formed defectively-- and the retorsion argument doesn't fulfill that condition-- so long as it appears they're formed reliably.The entire point of PC is that we don't need that kind of justification and that arguably such a justification would be impossible in any event. After all, how could I justify it? I cannot use my own rationality or perceptions to do so, as that would just be question begging. But nor could I possibly get outside myself or my rationality, so to speak, to justify it either. 

And if you see his section on the self-defeat argument at IEP, this makes sense. When we try to justify claims, if someone keeps pressing us for justifications of the justifications of the justifications, at some point the only possible answer is just going to be "Well, that's just how things seem to be." And so to reject the notion that appearances are sufficient for at least some justification in the absence of defeaters would actually undermine all knowledge claims.

Last edited by UGADawg (8/01/2017 2:48 pm)

Yeah, let me make it clear I don't think PSR is false, rather I just think the retorsion argument isn't conclusive, as you say. On the other hand Feser might have some response that could make it work. In fact I'd be surprised if he didn't update the argument in his forthcoming Five Proofs book. When Feser debated Keith Parsons, Parsons made a very similar objection to the one I'm making here. I don't think Feser ever responded, though of course that was largely because Parsons had the last word per the agreed upon rules of the debate. So it'd be pretty natural for him to include a response to this kind of objection, I would think, given that Feser seems to think it's one of the most important considerations in favor of accepting PSR.

​If I was arguing for PSR, though, I would still probably treat it as a first principle of rational inquiry in the way John Haldane does in his book with JJC Smart: whenever we find something that isn't self-explanatory we seek external explanations. And that just is PSR. So if we're going to abandon that for some specific scenario, e.g. to reject the cosmological argument, we'd have to provide a very good reason for doing so. That at least shifts the burden of proof on the denier of PSR.

I'm not entirely clear on why we'd have to take metaphysics to be prior to epistemology. I know Feser has sometimes briefly commented that any epistemology is going to rest on certain metaphysical assumptions, but I'm not sure that's conclusive, for we could also say any theory of metaphysics is going to rest on certain epistemological assumptions.

Last edited by UGADawg (8/01/2017 6:26 pm)

Jumping to this thread a bit late, I note that the subject was discussed in June 2016 by user RBrad and myself. On that thread, my position was stated in my last two posts, as my previous posts were not really addressing the core of the issue. As can be seen, my position is in agreement with that of UGADawg here. To sum it up, I will quote from my last post:

Johannes wrote:

The problem is that if a PSR denier should allow the PSR retorsion argument to instill in him doubts on his basic accuracy as fact perceiver, retainer and rational processor, his later acceptance of PSR would not be sufficient to clear those doubts, since reality might perfectly be thouroughly rationally explainable while he might still be an utterly defective fact perceiver, retainer and rational processor! Thus, if you allow the PSR retorsion argument to throw you down the hole of doubting your own intellectual faculties, then you cannot get out of that hole by just accepting PSR. Which shows clearly that you should not have allowed the PSR retorsion argument to throw you down that hole in the first place, the reason for the argument's unsoundness being that it implies the denial of not only PSR but also of basic realism.

Thus, assuming your basic accuracy as fact perceiver, retainer and rational processor is (at least an essential component of) a sound foundation for building your whole intellectual edifice, but radically doubting that accuracy and assuming just PSR is not.

Notably, your latest quote from Feser illustrates most clearly the break from realism implied in the PSR retorsion argument:

Feser wrote:

If there really could be unintelligible “brute facts,” then even the things we think are not brute facts may in fact be brute facts, and the fact that it falsely seems otherwise to us may itself be yet another brute fact.  We could have no reason to believe anything.

If, while in a forest, you believe that those ever-closer howls are unintelligible brute facts, and act in accordance to that belief by not taking any precautionary measures, you will promptly be eaten by the wolfs that explain the howls. So, you have the strongest reason to believe that the howls are not brute facts.

As the PSR retorsion argument implies a radical break from realism into pure rationality, its formulation can be described as a true Cartesian moment for Feser (and not "Parmenidean" as I wrote in my previous post, which I cannot edit now probably due to its length).

UGADawg wrote:

That said he gives a very brief formal version of the argument in the relevant section of the book when he says something to the effect of:

1. If PSR were false we could not trust our cognitive faculties.
2. But we can trust our cognitive faculties.
3. So PSR is true.

Elsewhere in the book when he's giving his views on conditions needed for knowledge claims, he says something like for S to know P, P must be true, S must believe P, and S's belief that P must be the result of some reliable process of thought formation. So I'm guessing Feser would say PSR being false means we don't know we believe what we do as a result of reliable processes of thought formation (which is similar enough to the premise 2 above). 

I still don't know if that works, though. What do you think?

It does not work against the usual denial of PSR, which amounts to assuming that reality is rationally explainable up to a point, usually the existence and laws of the universe, where we find a brute fact.

Referring to PSR, which amounts to assuming that reality is ultimately rationally explainable, as PSR-U (for "Ultimate"), and to the usual denial of PSR as PSR-L (for "Limited"), a holder of PSR-L wholly agrees with Feser about the argument 1..3 above, just replacing PSR with PSR-L. And clearly PSR-L being true is enough for us to be sure that we believe what we do as a result of a reliable processes of thought formation.

Thus, you can charge the usual objection to PSR with commiting what some apologetics sites call "the taxicab fallacy" [1], but you cannot use the PSR retortion argument against it.

I will add a couple of observations on this issue.

1. Some arguments for PSR, probably out of zeal to persuade, are actually inconsistent. The previously referred article [1], e.g., charges the "ultimate brute fact" position with:

- being inconsistent with their approach to facts of ordinary life,
- committing the taxicab fallacy,
- entailing radical skepticism about perception, and
- entailing a denial of rational argumentation, i.e. being subject to the PSR retortion argument.

It is straightforward that the charge of commiting the taxicab fallacy is mutually incompatible with the other three charges. It is also clear that most, if not all, deniers of PSR reject it only as it applies to the ultimate explanation of the universe, not to the explanation of facts within the universe, so that only the taxicab fallacy argument applies to them.

2. The term "taxicab fallacy" has an interesting history, which I learned from an article by an atheist blogger [2].

The first occurrence of a similar term seems to have been in a 2003 paper by Alexander Pruss [3], where he mentioned "Schopenhauer’s taxi-cab objection" against the Cosmological Argument, which was "that once the existence of the First Cause is inferred, the PSR is dismissed, like a taxi after it has brought us to our destination, instead of being applied to the First Cause or its creative act." Obviously that objection against the Cosmological Argument is baseless because the First Cause is a necessary Being.

The term "taxicab fallacy" itself seems to have been coined by W. L. Craig in a 2007 article [4]:

"W. L. Craig in [4 wrote:

"]1. Everything that exists has an explanation of its existence (either in the necessity of its own nature or in an external cause).
[...]
Premise 1 is the premise that the atheist typically rejects. Sometimes atheists will respond to premise 1 by saying that it is true of everything in the universe but not of the universe itself. But this response commits what has been aptly called “the taxicab fallacy.” For as the nineteenth century atheist philosopher Arthur Schopenhauer quipped, premise 1 can’t be dismissed like a hack once you’ve arrived at your desired destination!

Apparently the original quote referenced by Pruss and Craig is:

"Arthur Schopenhauer" wrote:

"Science is not a taxi-cab that we can get in and out of whenever we like."

As an aside, a blogger noted in 2012 that Schopenhauer "lived from 1788-1860, so it’s fairly doubtful he knew what a taxi was" [5], to which a reader answered in a comment: "Schopenhauer could have actually been familiar with horse-drawn taxi cabs during his lifetime. At least in London, small two-wheeled Hansom cabs were a fixture in the mid 19th century, through to the invention of the automobile. There were other designs before that, extending back into at least the 18th century." [5].

Clearly the original quote, featuring "science", was intended as objection to the Cosmological Argument, as mentioned by Pruss. Craig's appropriation of the quote in order to use it as argument for the PSR requires replacing "science" with "rational explicability". (As an aside, Craig does not make a clear distinction between physical and metaphysical explanations in that article.)

References

[1] Karlo Broussard. (2016, July 06). Why the Universe Can’t Be Merely a Brute Fact [Online].
Available: https://www.catholic.com/magazine/online-edition/why-the-universe-cant-be-merely-a-brute-fact

[2] neopolitan. (2012, September 19). The Misquoting WLC [Online].
Available: http://neophilosophical.blogspot.com/2012/09/the-misquoting-wlc.html

[3] Alexander Pruss. (2003, March 21). A Restricted Principle of Sufficient Reason and the Cosmological Argument [Online].
Available: http://alexanderpruss.com/papers/RPSR.html

[4] William Lane Craig. (2007, October 07). Argument from Contingency [Online].
Available: http://www.reasonablefaith.org/argument-from-contingency

[5] https://wickershamsconscience.wordpress.com/2012/11/23/fallacies-the-taxi-cab-fallacy/
 

Last edited by Johannes (8/31/2017 5:36 pm)