UGADawg wrote:

It's worth mentioning Feser does have two different arguments in support of PSR that claim we cannot have any principled reason for denying PSR while maintaining that there are at least some genuine explanations. [...]

Those may be sufficient to address what the denier of PSR is trying to do in accepting your PSR-L while denying PSR-U, and if so then they would either have to reject PSR entirely or accept PSR-U (because no principled reason for rejecting U but not L), in which case the retorsion argument may still work.

Of course PSR deniers "cannot have any principled reason for denying PSR". What they claim is that they do not have any principled reason for holding it either, i.e. that holding - as they do - that facts within the universe are physically rationally explainable does not require them to also hold that the universe itself is metaphysically rationally explainable.

IMV, while it is well known that the latter assumption leads straight to theism [1], it can be argued that it also pressuposes theism or panentheism. Because, why should we assume that reality is ultimately rationally explainable if not on the (at least implicit) assumption that Ultimate Reality is Logos, i.e. Reason [2], by/of Which everything was created/emanated, and in the image of Which human reason has been created/emanated? Of course, the panentheistic flavor of the underlying assumption can then be corrected to classical theism by reasoning based on the PSR [3].

Thus, IMV the teaching in First Vatican Council's Constitution "Dei Filius" "that God, the source and end of all things, can be known with certainty from the consideration of created things, by the natural light of human reason "for his invisible attributes, ever since the creation of the world, have been clearly perceived, being understood through the things that have been made."" (ch. 2 "On Revelation", which in turn quotes (Rom 1:20)) presupposes the implicit condition "if the person in question assumes that reality is ultimately intelligible/explainable by human reason".

Now, the atheists' position is further weakened when science shows that the universe must have had a beginning in time, so that a creative act by God is needed not only as metaphysical explanation for the existence of the universe but also as physical explanation for its beginning. But metaphysicians seem to have little regard, if any, for this line of argumentation.

Notes

[1] Prof. Feser once stated that "to see the world as intelligible or rational through and through is implicitly to be a (classical) theist".
http://edwardfeser.blogspot.com/2014/10/could-theist-deny-psr.html

[2] I am referring to Logos (in the sense of Reason) as a divine attribute synonymous to Wisdom (Sophia), which by absolute divine simplicity is identical with the divine essence, and not to Logos (in the sense of Word and also of Reason) as a divine Person in trinitarian theology. Benedict XVI used the term "creative Reason" in this sense in his answer to the last question in this 2006 meeting, where he stated a view similar to the one I stated here:
http://w2.vatican.va/content/benedict-xvi/en/speeches/2006/april/documents/hf_ben-xvi_spe_20060406_xxi-wyd.html

[3] An instance of the panentheistic flavor of the underlying assumption behind PSR was the position of Scott Ryan, moderator and patron saint of this forum, in his 2003 book Objectivism and the Corruption of Rationality: A Critique of Ayn Rand's Epistemology, pp. 390-393.
Available: https://books.google.com/books?id=re02xxLU_MEC
 

Last edited by Johannes (9/05/2017 8:07 pm)

Actually, atheists have been willing to do exactly that since long ago (see appendix below).

Personally, I think that arguing for PSR is to no avail, first because atheists see that it leads straight to theism, and secondly because, as I said, it may itself presuppose theism or at least panentheism.

Now, if your real goal is to argue for the existence of God, there are other ways. After all, St. Paul's statement that "His invisible qualities, both His eternal power and divinity, are clearly seen, being understood through the things that have been made" (Rom 1:20) is not restricted to the cosmological argument from contingency. Moreover, can't our advancement in the knowledge of "the things that have been made" play a role in this understanding?  I'm thinking about:

- Ever stronger evidence of an absolute beginning of the universe in time, which requires God not only as metaphysical explanation for the existence of the universe but also as physical explanation for its beginning. (If interested, see https://arxiv.org/abs/1705.00192)

- Reinforcing the previous point, conclusive evidence since 1998 of the acceleration of the expansion of the universe, which discards the possibility of an eternal cyclic universe whose last "big bang" was a bounce from a "big crunch". Because if the "current instance" of the universe will expand forever in an exponential regime, it is against reason to assume that there was a "previous instance" which entered a phase of contraction.

- The fine tuning of the universe for the development of intelligent life. Though this argument may be dismissed by positing a multiverse, that hypothesis is just as outside science as God's.

- The mathematical structure of the laws of nature, as pointed out by Benedict XVI in his last answer in this meeting:

http://w2.vatican.va/content/benedict-xvi/en/speeches/2006/april/documents/hf_ben-xvi_spe_20060406_xxi-wyd.html


Appendix. Examples of atheistic positions based on the assumption that reality is not ultimately rationally intelligible/explainable.

1. David Hume's position as summarized by Texas A&M University Prof. of Philosophy Stephen H. Daniel in option 101.(b) in
http://philosophy.tamu.edu/~sdaniel/quesrel.html

"(b) The argument assumes that the world's existence can be explained rationally by appeal to God as its cause; but why should we think that the world's existence is rationally explainable?"

2. Bertrand Russell's position in his famous debate with Fr. F. C. Copleston:
http://www.scandalon.co.uk/philosophy/cosmological_radio.htm

"R: The whole concept of cause is one we derive from our observation of particular things; I see no reason whatsoever to suppose that the total has any cause whatsoever.

R: what I'm saying is that the concept of cause is not applicable to the total.

R: I should say that the universe is just there, and that's all.

R: for my part, I do think the notion of the world having an explanation is a mistake. I don't see why one should expect it to have,

C: But your general point then, Lord Russell, is that it's illegitimate even to ask the question of the cause of the world?

R: Yes, that's my position."

3. Prof. Sean Carroll's position, as stated in 2007:
http://www.preposterousuniverse.com/blog/2007/11/25/turtles-much-of-the-way-down/

"There is a chain of explanations concerning things that happen in the universe, which ultimately reaches to the fundamental laws of nature and stops. ... There is a strong temptation to approach the universe with a demand that it make sense of itself and of our lives, rather than simply accepting it for what it is."

4. Prof. Sean Carroll's position, as stated in 2012:
http://www.preposterousuniverse.com/blog/2012/04/28/a-universe-from-nothing/

"It’s okay to admit that a chain of explanations might end somewhere, and that somewhere might be with the universe and the laws it obeys, and the only further explanation might be “that’s just the way it is.” ... I could be wrong about that, but an insistence that “the universe must explain itself” or some such thing seems like a completely unsupportable a priori assumption."
 

Hi Jeremy

Yes, I do think we do eliminate those scenarios in practice, and, as I believe I mentioned elsewhere in this topic, Feser does present the argument similarly to Reppert's in his formal presentation of the rationalist proof (in his new Five Proofs book). It's essentially: (a) If PSR is false, then we cannot trust our cognitive faculties. (b) But we can trust our cognitive faculties. (c) Therefore PSR is true.

I don't think anyone could reject premise (b) without undermining themselves. The question is whether (a) is true, and that involves cashing out exactly what denying PSR entails w.r.t. the reliability of our cognitive faculties. The problem, I think, is that denying PSR doesn't entail our cognitive faculties are actually unreliable, rather it entails they're possibly unreliable. Or perhaps at most it entails that we can have no reason for thinking they're reliable, or perhaps that the probability of our cognitive faculties being reliable is inscrutable, etc. 

But I think many epistemologists would happily accept this. Certainly the mere possibility that ~P doesn't undermine our justification in believing P, otherwise all our knowledge would be undercut. And I don't even know that it's problematic if we agree the probability that our faculties are reliable is inscrutable. After all, what reason could we possibly appeal to in showing it's likely our faculties are reliable that wouldn't presuppose their reliability? So in short, the possibility that our faculties are unreliable, or perhaps inscrutability w.r.t. the the reliability of our faculties, might not commit us to the position that we cannot trust our faculties. Therefore we might have grounds for rejecting or doubting (a), even if we haven't conclusively shown it to be false.

Now, Feser might have answers for all these questions. But I think at the very least what I'm trying to illustrate here is clear in the sense that the retorsion argument really raises more questions than it answers. I don't think the brief one paragraph argument in his Scholastic Metaphysics or Five Proofs is really sufficient to make the argument compelling without getting into deeper epistemological issues.

Last edited by UGADawg (9/13/2017 12:40 am)

Jeremy Taylor wrote:

If we hold a position that implies we can't know if we can generally trust them, or have no reason to generally trust them, then this position does conflict with (b) 

Well, I'm not sure this is correct, at least perhaps not in the sense in which you mean it. If you look elsewhere in this topic, for instance, you'll see that I've discussed Michael Huemer's view of epistemology called phenomenal conservatism. I won't repeat what I've already said, so I'd direct you to those posts, but the general emphasis is just that one can be justified in trusting one's cognitive faculties solely on the basis that it appears that they're trustworthy or reliable, so long as there are no defeaters offered for that appearance. 

And it's not clear at all how PSR being false would undermine that appearance. To do so it would need to either (a) provide evidence the appearance is false; or (b) provide evidence the appearance was formed due to defective or unreliable processes of thought formation. ~PSR certainly doesn't satisfy (a), as it in no way entails our faculties are actually unreliable. And I'm not sure how it would satisfy (b) either, given that it just raises the possibility that our thoughts are unreliable, and again, doesn't give any positive reason to think this is actually happening.
 

Well, I think my point is that if Huemer's view is accepted (that S has some justification for P if P appears to be true and there are no defeaters for P) then it's not clear to me how one would be unjustified in accepting that one's cognitive faculties were reliable on the grounds that it appears they're reliable even if PSR is assumed to be false, because PSR being false does not seem to either provide what Huemer calls a rebutting defeater or an undercutting defeater (see the IEP article on phenomenal conservatism for explanation).

Also it looks like there's a discussion of the retorsion argument on Feser's blog in the comments for anyone interested. http://edwardfeser.blogspot.com/2017/09/radio-activity.html

The user "Tyler" has some interesting thoughts that are similar to mine.