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Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/09/2018 10:48 pm

UGADawg
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Also, since we're discussing the modal collapse argument, I'm curious what you think of Vallicella's way of defusing the problem: http://maverickphilosopher.typepad.com/maverick_philosopher/2016/05/explanatory-rationalism-and-the-collapse-of-modal-distinctions.html

Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/09/2018 8:54 pm

UGADawg
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If P explains Q, and there are possible words with P but not Q, given PSR there must be some reason Q doesn't follow from P in those possible worlds (otherwise brute), which he's calling a defeater. In every possible world with P & no defeater, then, Q obtains as well. So if there are no contingent defeaters it's an entailment.

At least that's how I understand him. If I can get in touch with him I'll ask him if he ever formally checked it with a computer; he's literally a professional logician, though, so I tend to trust his intuitions when it comes to formal logics.

Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/09/2018 5:25 pm

UGADawg
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Miguel with the "a true explanation that succeeds entails the truth of what it explains" he's just talking about those explanations that account for all their possible defeaters. He's not assuming, prior to the argument, all explanations are entailments; rather he's arguing that for any situation in which an explanation accounts for all its contingent defeaters (and it must have contingent defeaters in the first place, otherwise it's already an entailment), and the explanation is true, then all the defeaters must be false, so we have an entailment. This kind of situation obviously holds for the relationship between E and the BCCF, therefore it's an entailment.

Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/09/2018 4:08 pm

UGADawg
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FWIW it's not exactly difficult to prove the move from the necessary being to the BCCF must be an entailment, even if we allow that some explanations aren't entailments. To quote from one of my friends:

What I'm trying to get at is if explanation are (sometimes) not entailments, then it's possible that they fail, even when the conclusion is also true - the explanation from P to Q has defeaters. In the example I gave, even though someone being pushed off a building explains that he died, and he did die, it was defeated by the man being shot on his way down. And, if the PSR is true, there is a fact to whether or not any given explanation is defeated for each defeater, and these facts must have an explanation. 

Therefore, given the explanation E, for the Big Conjunctive Contingent Fact (BCCF), I believe we can demonstrate that it is an entailment, if we accept than an explanation that gives an account of every possible defeater of it, forms an entailment. I haven't sketched out the formal proof of that part, but it seems reasonable - if it's impossible for there to be any other ways for the explanation could fail, then we know whether it does in fact succeed or not. And a true explanation that succeeds entails the truth of what it explains. 


i) An explanation with necessary defeaters or no defeaters is an entailment (as it would either always succeed or never succeed). 
ii) Therefore, if E is not an entailment, it must have contingent defeaters.
iii) Therefore, the defeaters of E are part of the BCCF
iv) Therefore, E explains the defeaters of E
v) Therefore, E is an entailment.

Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/08/2018 7:47 pm

UGADawg
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Also forgot to just say I thought the article was very good and raises pertinent issues. I think you're entirely right that Feser moves far too quickly through the modal fatalism objection. You also made a point I've been trying (and failing, evidently) to make for a while now, which is that the retorsion argument requires a great deal of fleshing out in terms of the details before it becomes fully convincing. 

Theoretical Philosophy » Five Proofs Critique - PSR Argument » 1/08/2018 4:25 pm

UGADawg
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Daniel what do you think of the claim that modal collapse arguments rest on a fallacy of equivocation on the notion of necessity, namely between absolute or metaphysical necessity on the one hand, and hypothetical or physical necessity on the other? One of the papers Feser cites in his discussion, Gerson's Two Criticisms of the Principle of Sufficient Reason, explicitly makes this point. To get a PSR style cosmological argument to work, one is explaining contingency in terms of dependence relations, which ultimately terminates in a metaphysically necessary entity, so even if PSR entails all beings are hypothetically necessary, it would by no means block the cosmological argument.

To be sure this would involve accepting necessitarianism, although it's not clear why that would be objectionable from the point of view of many atheists who are already committed to, or at least see no significant problems with, determinism. Some theists may find this objectionable insofar as it undermines libertarian notions of free will, though I'm not sure that's especially problematic; Leibniz certainly didn't think so.

Theoretical Philosophy » Feser's retorsion argument for PSR » 1/04/2018 11:12 am

UGADawg
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Miguel it's definitely not question begging and your response just seems to miss the point.

Edit: Should've expanded on this, I suppose. What I mean by it not begging the question is that pointing out the reasons you offer in response to the evil demon hypothesis could itself be products of the evil demon does not seem to presuppose said responses are false. For instance, take the point that the ED is less parsimonious and therefore not a very good explanation of our experiences compared to the usual explanation; even if this is true, this just gives us some reason to think the ED scenario is less likely to obtain. It doesn't imply, with deductive certainty, that it doesn't obtain, and so I don't see how pointing out the possibility the ED scenario could still obtain, and therefore possibly be causing the belief that it's less parsimonious, is presupposing the falsity of the arugment. Indeed it seems they're logically consistent in the relevant sense.

Theoretical Philosophy » Feser's retorsion argument for PSR » 12/31/2017 7:09 pm

UGADawg
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After thinking on this some more, is there not a way the critic of the retorsion argument could insist the charge of begging the question is odd?

For example Miguel you mentioned how evil demon scenarios might be rejected on the grounds that that they are objectively improbable, or on the basis that they provide an inferior explanation insofar as they are positing unneeded entities, etc. But couldn't the skeptic charge this response with a similar kind of circularity, i.e. in making these claims you're presupposing you can make the relevant judgments concerning the weighing of probabilities or explanatory adequacy, which presupposes you're not being misled by the demon?

There's sort of an inherent difficulty in attempting to reason about something that necessarily stands outside of it.

Theoretical Philosophy » Feser's retorsion argument for PSR » 12/31/2017 4:35 pm

UGADawg
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I'm not sure you're right about Kant. It's not that he's supposing PSR is true for phenomena and not other objects, rather he's arguing PSR is a necessary condition for any possible objects of experience, and so, insofar as we experience them, it must be the case that PSR holds for them.

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