PSR thread

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Posted by Miguel
5/07/2018 9:02 pm
#1

Thread dedicated to discussing our favorite obsession. Share arguments and thoughts.

What do you think of using Pruss's Weak Weak Principle of Sufficient Reason as an argument for PSR?

The Weak Principle states: for every contingent truth p, p possibly has an explanation.

So p doesn't have to actually have an explanation, but at least it should be possible for it to have one. Now, WPSR entails PSR, because if X has no explanation, then the conjunction of X with the claim that X is unexplained not only has no explanation, but cannot have an explanation. (Since if it could have an explanation then there would be a contradiction, as X would both be explained and unexplained). But, contra Oppy, this should actually make us accept PSR, since it follows from such a modest and intuitive principle as WPSR.

Then there's the Weak Weak PSR. WWPSR states that WPSR is possibly true. That, however, is sufficient for entailing PSR.

(Of course, one could also use WWPSR directly in a cosmological argument and then argue that the necessary being, by S5, exists in the actual world)

Is there any other principle that has such a comparable support? A PSR skeptic would have to hold that it's impossible for every contingent truth to even possibly possibly have an explanation.

 
Posted by Miguel
5/07/2018 9:14 pm
#2

One could also argue from a very limited principle: anything that *can* have an explanation actually has an explanation. This avoids problems with BCCF, for example.

But then what about the existence of contingent things? What about the question "why do things exist?"? If it can have an explanation, then it has such an explanation. But that implies PSR is true, at least a PSR for contingent things.

 
Posted by Miguel
5/07/2018 9:42 pm
#3

We could also use Weak Weak Weak Weak Weak Weak Weak PSR. The WWWWWWWPSR says that it is possible that it is possible that it is possible that it is possible that it is possible that it is possible for every contingent truth p to possibly have an explanation, and we can run from there. We could also use the Weak Weak Weak Weak Weak Weak Weak Weak PSR, which states that WWWWWWWPSR is possibly true, and argue directly to a necessary being from S5

 
Posted by seigneur
5/08/2018 1:14 am
#4

I'm not that obsessed with PSR. It may very well be that everything has an explanation, but this does not mean that we are going to find it. Still, the rational way of going about things is with explanations. This is my PSR.

 
Posted by aftermathemat
5/08/2018 7:18 am
#5

seigneur wrote:

I'm not that obsessed with PSR. It may very well be that everything has an explanation, but this does not mean that we are going to find it. Still, the rational way of going about things is with explanations. This is my PSR.

The PSR as argued for by theists does not state that the explanations of things must be understandable or findable in principle.

It just states that everything  has  an explanation, not that we are necessarily able to find it out. To infer from the existence of explanation to the knowability of that explanation by us one must believe in something additional to the PSR, something the medievals called the  adequatio intellectus ad rem - the adequation of the intellect to things, i.e. the idea that our categories of thought in some sense map and reflect reality as it is.

 
Posted by aftermathemat
5/08/2018 7:27 am
#6

Miguel wrote:

Thread dedicated to discussing our favorite obsession. Share arguments and thoughts.

One of the interesting things I noticed is that we tend to use explicability arguments for existence as well as explicability arguments for other things.

How? Imagine you created 2 small rooms that are completely empty, and you isolated both rooms from any and all possible external causal and explanatory influences that could generate any new objects or disturbances within them. And let's say you also removed any and all possible causal and explanatory influences inside the rooms as well, such that you are guaranteed to have the rooms be simple rooms where nothing happens inside of them.

Let's say you close yourself up in room 1 for five minutes. Nothing happens.

Now close yourself up in room 2 for five minutes. You would expect nothing to happen, no bricks materialising above your head, no strange sounds appearing for no reason, no interferences whatsoever. 

Yet this is an explicability argument that rules out objects starting to exist / just appearing for no reason and interfering with your experiment. What this entails is that we already accept explicability arguments for the existence of things, and as such the contingency argument goes through on that intuition.


2) Another interesting thing I noticed is that in all explicability arguments, the thing that is problematic is the inexplicability / bruteness of the things that are rejected. 

It's not that an Archimedian scale cannot fail to balance if equal weights are on it (since it surely can fail to balance if a certain object were causing the other scale to stay up, if the screws on the second part of the scale aren't properly attached and are preventing the second scale from working, etc.), and it's not that a dissolvable tablet cannot possibly fail to dissolve in the water (since there can be causal / explanatory influences that can cause that to happen), it's that these things cannot happen because they do so  inexplicably.

It's the inexplicability that's the problem, not the events that happen. So explicability arguments are arguments that generally go against inexplicability / bruteness  as such, rather than being merely localised in a given particular case. The same applies to the existence of things. So it seems that the very absurdity of inexplicability is something that universalises on all domains, not just on local cases as presented by Della Rocca.

I am pretty sure that if you were to ask an average non-theist on the street, say an agnostic that isn't hostile to religion and just doesn't care much either way and also doesn't know much about the various arguments pro and con either, he would pretty much reject the idea that something can start existing inexplicably as much as he would reject the idea of a dissolvable tablet failing to dissolve inexplicably. 

The issue would be the inexplicability, no matter what area it happens to allegedly be in.

Miguel wrote:

What do you think of using Pruss's Weak Weak Principle of Sufficient Reason as an argument for PSR?

I am a bit skeptical with regards to Pruss's arguments for God on the basis of the sheer possibility of principles that imply God's existence. They remind me a little bit too much of the ontological argument and it's attempt to prove that God exists from the sheer possibility of a necessary maximally great being existing.

I guess I just don't see how the sheer possibility of a necessary being existing can somehow be modally manipulated to entail that the possible necessary being is an actual necessary being by the sheer possibility of it's own necessity.

In the same way, I don't see how the sheer possibility of the existence of things having an explanation and there possibly being a necessary being that explains existence somehow entails that there really is an actually existing necessary being from the sheer possibility of it.

Last edited by aftermathemat (5/08/2018 7:39 am)

 
Posted by Hypatia
5/08/2018 9:58 am
#7

My concern with this particular argument is that there seems to be some equivocation with the meaning of the word "possible." From an epistemological standpoint, is it possible that PSR is true? Assuming that any argument against it can be defeated, then yes. We're not in a position to declare it false.

However, from an ontological perspective, is it possible that PSR is true? No, since possibility entails contingency. The choices are necessary and impossible--God is not like a horse that could possibly exist in one universe in fail to exist in another. I think ontological arguments are really good for demonstrating this, but I do not see how strengthening the argument that God is possible from an epistemological standpoint could ever affect the second question.

I am suspicious of S5 logic in general, though, except insofar as it concludes that something cannot be both necessary and possible at the same time.

 
Posted by Miguel
5/08/2018 11:32 am
#8

But we don't even need S5. Though I have no problems at all with S5 (it's quite obvious to me that if a necessary being possibly exists then it does in fact exist; to me the problem with OA is arguing for the first premiss specifically, but it can be good to combine with cosmological args like those), the thing is that WPSR entails PSR and you don't even need S5 to do so.

I don't think you are correct in saying PSR would not be ontologically possible because it's necessary. Every necessary fact or object that is actually the case is by definition possible. An actual necessary being would exist in every possible world, but obviously would also exist in at least one possible world, satisfying the definition. If PSR is true then it is obviously also possible, and ontologically so, because if it were not possible ontologically then it wouldn't be actual at all. Possibility here need not imply potentiality as in the A-T framework. (If however one insists on ground alethic modality in aristotelian powers etc, then we could run Pruss's argument for PSR from that theory)

Regardless, we can use epistemic possibility as a guide to ontology, and we generally do so. It can be defeasible and need not be failproof, but the idea is that if we can at least conceive of something being the case, then we have some reason to regard it as possible. (But it's defeasible. The problem with Hume's argument, in my view, is that we can't really conceive what he's asking us to conceive - cf. Anscombe - and still that wouldn't be enough to deal away with reasons we can have for holding PSR - self-evidence, inductive generalization, the fact that there is no arbitrary chaos happening right now, etc)

So if WPSR is possibly true, which to me seems self-evident and very hard to deny, it would be possible that every contingent fact could at least have an explanation even if it were not the case that every cf actually had an explanation. But that entails the actual PSR. I don't see how it would be reasonable to reject WWPSR.

Last edited by Miguel (5/08/2018 11:35 am)

 
Posted by DanielCC
5/08/2018 12:17 pm
#9

Re the Gale-Pruss PSR think of it as the claim that for any contingent being that exists possibley its existence has an explaination (to get away from PSR language for any contingent being that contingent being could have been bought into existence by another). The upholder of this principle could grant Hume’s conceivability argument about the brick as they only need insist that said brick could have been brought into existence with a cause (after all we encounter plenty of bricks that are).

The big problem here is with orgins essentialism. If individual beings have their origins essentially it significantly weakens the case for Gale-Pruss PSR being that different from the normal PSR. Not only would bricks that come to be without a cause have that property necessarily but even bricks produced by regular methods would not have been able to come about in slightly different circumstances e.g. by being the work of a different brick cutter or coming from a different batch of clay.

 
Posted by aftermathemat
5/08/2018 12:21 pm
#10

Miguel wrote:

 Every necessary fact or object that is actually the case is by definition possible. An actual necessary being would exist in every possible world, but obviously would also exist in at least one possible world, satisfying the definition.

I think I would have to disagree with that. Necessary facts aren't  "possible",  if by that one means they are like abstract possibilities and contingent beings. Necessary facts come prior to and before contingent facts, and they actually tell us what is possible and what is not possible, since they are grounded in the Divine Nature, and as such are logically prior to abstract possibilities.

 


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