## Monday, April 8, 2019

### The probability of the universe popping into existence

Consider the hypothesis that contingent reality popped into existence uncaused.

Now, either popping into existence uncaused is astronomically unlikely or not astronomically unlikely.

If it is astronomically unlikely, then we have a very strong Bayesian argument for theism. For then P(contingent reality | no God) is astronomically small while P(contingent reality | God) is at least moderately high.

If uncaused popping into existence is not astronomically unlikely, then there are two main options. The first option is that there is no meaningful probability of such an event. In that case, there is no meaningful probability of Maxwell’s Demon popping into existence for no cause at all in one’s lab. But if Maxwell’s Demon were to pop into existence in one’s lab, then one wouldn’t expect to get the predicted observations. Thus, if there is no meaningful probability of things popping into existence for no cause at all, then there is no meaningful probability of our scientific predictions, and science falls apart. That’s not acceptable.

The other option is that there is a probability, and it’s not astronomically small. But then at every moment of time, it is not astronomically unlikely that an object would causelessly pop into existence. Since there are astronomically many moments of time during a second (perhaps infinitely many, but at least equal to the number of Planck times in a second, i.e., of the order of 1043), it seems we should expect to see lots of objects pop into existence causelessly. And we don’t observe that.

There is lots of technical detail to fix in this argument.

Wesley C. said...

It's not just the popping into existence at the beginning that is uncaused, though. The continued existence of anything at every moment is also uncaused, meaning that a similar analysis applies to the momentary / continued existence of things.

If the continued existence of things at any moment is unlikely, then the universe should have stopped existing a long time ago. Or it should be expected to stop anytime soon now. If there's no meaningful probability, then our common-sense judgement that reality will continue to exist in the future is false and we should be agnostic about it's continued existence.

If the probability is that it is quite likely that existence will continue, then we still should have seen things ceasing to exist, because the probability should have been exhausted by now, or we should expect it to be. A deck of 10 cards, out of which 8 are aces and 2 are jokers cannot constantly yield aces all the time, but must give in to the jokers eventually.

Walter Van den Acker said...

Alex

I don't think popping into existence is possible at all, but there is one thing in your post that I believe is wrong. If the chance of contingent reality popping into existence is not zero, then P(contingent reality|God) is not moderately high. In fact, in that case, P(contingent reality|God) is zero. If there is a non-zero chance of an alternative for an alleged necessary being, then such being is impossible and that's because if X can pop into existence, there is no reason why wX (a world with only X and nothing else) is not possible.
And if wX is a possibke world, God isn't necessary and hence God doesn't exist.

Of course the proponent of popping into existence can always say it is a mystery why we don't see more things popping into existence.

Red said...

I really like this sort of argumentation but I guess this needs a more fine-grained analysis of Popping into existence to be really convincing.

IanS said...

Alex:

I’m not following. No doubt I have missed some points.

I’m assuming that ‘contingent reality’ means this world, or perhaps some suitably similar world.

Surely an advocate of popping would distinguish popping of worlds (i.e. from nothing) from popping of things (like Maxwell’s demons) into existing worlds. Why should we treat them as similar? Common observation tells us that not much popping happens in this world, at least of macroscopic objects. But we have (and can have) no experience relevant to the popping of worlds from nothing. So that is open for philosophers to speculate on.

Planck time (or anything based in this-world physics) is surely irrelevant to the popping of this world (if indeed it did pop). Only ‘God’s time’, so to speak, or something outside time could be relevant to that.

Atno said...

I think an atheist could try to resist this argument by rejecting that the universe "popped into existence". He might accept a limited causal principle to the effect that everything that begins to exist has a cause, while resisting a full-blown PSR. So he can avoid skeptical scenarios such as the idea that there would be no meaningful probabilities for things coming into being in front of us in the next second, etc. Oppy argues that the atheist could limit causal principles to things that begin to exist, or perhaps "non-first" events.

But I think we can develop chaotic scenarios that might include eternal contingent things, and perhaps even general states of affairs such as the existence of any totality of contingent things. Wesley mentioned persistence, for example. If (even eternal) contingent reality has no probability for its existence, then we could not say it is improbable that it will continue to exist in the next second - if it is possible for things to cease to exist.

Or perhaps we can consider this scenario: if no meaningful probabilities attach to the unexplained existence of the totality of contingent things, then we cannot say it is improbable that our universe has always had a crazy fundamental law (or crazy particles) with the effect of changing all water molecules into some kind of acid after April 10th 2019. But that is crazy and would violate all our expectations. So we must hold that contingent reality, even if eternal, has an explanation (or some probability for its existence).

Someone might reply that a property involving a specific date like "April 10th 2019" cannot be a real property attaching to any law, but we can say that this is just a manner of speaking; metaphysically, the crazy law is such that its effects have a certain duration, taking some time to actualize the crazy results (perhaps in the next second). This type of law seems possible.

If the hypothesis that our contingent reality has a crazy law like that has no meaningful objective probability, then we need to assume a full-blown PSR to rule it out. Otherwise we cannot say it is improbable that we live in a chaotic contingent totality.

What do you think?

Alexander R Pruss said...

A number of commenters have suggested a difference between the universe popping into existence and a particular object in the universe popping into existence. The differences I see are that it should be *harder* for the universe to pop into existence. The universe has more energy than any particular object. And its popping into existence requires the popping into existence of spacetime as such, while a particular physical object coming into existence can make use of a preexisting spacetime for its location.

I like this thought experiment. Imagine a universe that is just a single walnut. That universe shouldn't be any harder to have come into existence causelessly than our universe. but if the walnut universe can come into existence, why can't an ordinary walnut do so now just as easily, or more easily?

Wesley: It seems plausible that the existence of things at earlier times causes the existence of things at later times.

Walter: Good point. What we really should compare are the probability of something popping into existence for not cause given atheism (for on theism, such popping is impossible as you note) and the probability of there being a contingent reality given theism. The "given" in both cases indicates an epistemic conditional probability.

Miguel: Another move, without supposing any weird laws of nature, would be to consider the possibility that when the world popped into existence, then the initial state was such as to throw off all our predictions as of tomorrow. Specifically, it could be that at the beginning there was some gigantic source of high energy particles that was just outside the backwards light cone centered on the earth today, but within the backwards light cone centered on the earth tomorrow. If we cannot assign any meaningful probability to this, then all our ordinary projections for tomorrow will be off.

Red said...

Isn't there a difference between universe popping into existence and it simply having a temporal boundary in the past without having a further explanation? or Are these two cases equivalent?

And what exactly is meant by universe in this particular argument, some particular narrow scientific understanding or just another name for the all the contingent beings of the actual world?

Alexander R Pruss said...

The main difference is that in the one case there may be even earlier times and the other case there are not. But earlier times only make it EASIER for the universe to come into existence, since if there is an earlier time, at least there is something, so we don't have a complete _ex nihilo_.

Universe = sum total of all contingent beings.

Wesley C. said...

Alex,

You say, "It seems plausible that the existence of things at earlier times causes the existence of things at later times."

How can the existence of something at one point in time cause it's existence at a later time? The object clearly cannot be it's own source of existence at any point (as self-causation is incoherent), and it seems awkward at the very least to view the object's very existence as a cause of even further existence. And isn't what you're proposing existential inertia?

If so, that would contradict many of the traditional cosmological arguments that argue God is the sustaining cause of the existence of things at any moment it exists.

Alexander R Pruss said...

Wesley:

A couple of minutes ago I came into this room. Thus, a couple of minutes ago I caused myself to occupy this location in space. Why is it any more mysterious that I should cause myself to occupy a particular location in time? (Maybe because you think time is very different from space. I don't.)

If a dog saves the life of a cat, then the dog is a cause of the cat's future existence. This doesn't seem to be at all problematic metaphysically. But if the cat later saves the dog's life, then the dog could well be the cause of its own future existence.

Of course, on Thomistic views about the relationship between divine and creaturely causality, this causation--like all causation--will only function because of divine cooperation.

IanS said...

Alex:

One reason that it is hard for a walnut (or any macroscopic object) to pop into this world is that this-world physics makes it hard. But popping ex nihilo (if it happened) would not have been constrained by this-world physics. (Note that if this world had popped, it is not just ‘stuff’ that would have popped, but space-time and the laws of this-world physics.) So it is not obvious that the difficulty of popping ex nihilo would have had any particular relation to that of popping into this world.

A note on energy. Some cosmologists think that the universe has zero energy – positive mass-energy is balanced by negative gravitational energy. In any case, energy is a concept in this-world physics. If the world had popped, this world-physics would not have applied to the popping.

Walter Van den Acker said...

Alex

"Popping into existence" is either possible or it isn't. I don't think probability is all that important here.
Sure, the probability of a contingent reality may be (much) higher given theism, but only if it is possible for something to come from nothing. If ex nihilo nihil fit is true, then neither scenario is possible.

Alexander R Pruss said...

Ian:

I can kind of see how the laws of physics can constrain the causal activity of existing things. But I don't see how they can stop a non-existing thing from causelessly coming into existence.

Of course, it's very much a mystery how laws of nature do any constraining...

Wesley C. said...

Alex:

Divine cooperation is what I was getting at in my first comment. What you're describing in the space-occupation scenario and dog-cat life saving scenario is secondary causality. But such causality depends on God's conservation at every moment it exists. So the argument was that the continued conservation of anything in existence is also susceptible of your probability analysis in the OP, since it's fundamentally existential as well.

It also doesn't matter what time theory one prefers. The B-theory only reframes the continued existence of things in terms of continued extension rather than temporal duration, but the same principles of divine conservation and existential explanation apply.

Atno said...

Regardless of whether or not the existence of things at earlier times could cause their existence at later times, wouldn't this be a contingent fact? And if so, even the eternalist should entertain the possibility that things could cease to exist in the next second. It seems possible for every contingent thing to fail to exist in the next second. It is possible for all things which exist at earlier times to not cause their existence in the next second. (Or perhaps we could put it like this: our universe could be such that it extends all the way up until tx, even if it had always existed before that... And other universes could be such as to extend beyond tx).

If there is a contingent possibility for the universe to cease to exist in the next second, and no probability attaches to that, we would have a chaotic scenario. Unless the eternalist thinks contingent things at earlier times *have* to keep sustaining things at later times.

Walter Van den Acker said...

Miguel

I find the idea of something ceasing to exist just as counterintuitive as something popping into existence.

Alexander R Pruss said...

Wesley:

On theological and philosophical grounds, I think all creaturely causation depends on God. But I do not know how to argue for a need for such dependence without presupposing the existence of God.

Wesley C. said...

Alex:

That's actually rather easy to do. The foundational premises of many Thomistic (and non-Thomistic) cosmological arguments is that the existence of contingent beings in the here-and-now requires a cause or explanation.

The arguments, without even having proven God at that point, point out that the existence of things at any moment in time requires a cause, precisely because of their contingency. And that their contingency (they could conceivably stop existing at any moment) shows that they don't have existence as if by inertia.

The here-and-now existence of things requires a cause just as much as their first popping into existence does.

Alexander R Pruss said...

I agree that the here-and-now existence of things requires a cause. But why can't that cause be contingent things (the same ones or different ones) at an earlier time?

It may be true that all contingent things could conceivably stop existing at any moment. But it is not clear that they could do so without something exercising a causal power to annihilate them.

Wesley C. said...

Because contingent things at an earlier time aren't strictly speaking the cause of existence of later things. If everything that exists at every moment requires a conserving cause, then the cause cannot be yet another contingent thing from a previous point in time - that confuses accidentally ordered causation with essentially ordered ones. A dog might be the cause of the cat's continued existence at a later point in time, but the cat's existence strictly speaking is not caused by the dog at any moment at all.

Well, if brute facts are possible, then that might as well happen in the next five seconds for no reason. The continued existence of things is an activity, and the ceasing to be of something is for an activity to cease. And in that sense the ceasing to be of something is not a positive action that occurs, but the stopping of something altogether.

Wesley C. said...

To clarify my first point, what I mean when I say that the dog isn't the cause of the cat's existence is that the dog isn't what actually conserves the cat's existence in being at any moment.

The dog is a cause of existence only in a secondary, analogous sense - his saving the cat's life ensures that the cat will continue to live, but only insofar as God continues to conserve it in being. God could, after all, in principle remove existence from the cat at the moment the dog saves it's life.

Atno said...

Walter,

To me it is kinda analogous to the idea of a contingent reality existing without any cause or explanation. If a contingent possibility can simply be real with no cause, I see no reason why it cannot cease to be real with no explanation. Otherwise it would be like saying that it is a necessary fact that if there is a contingent reality, this contingent reality must necessarily continue to exist. I see no reason whatsoever for accepting this principle, and it in fact seems false to me. If X is a contingent being, and its existence at t0 isn't therefore necessary,nits existence at t1 also shouldn't be necessary. Its non-existence would be possible at any moment, whether or not it is actualized; but then it should be possible for X to cease to exist.

I think this scenario could still be a problem even if things at earlier times cause things at later times. (But to be frank, this view of causation seems to me very odd. I'm inclined to think all causation is simultaneous, and so if I'm supposed to exist at t1, I need to be caused at t1, not at t0).

Walter Van den Acker said...

Miguel

I don't think that, as far as beginning or ceasing or exist is concerned, the difference between necessary and contingent is all that relevant. What matters is existential inertia. If something exists, as Alex says, it is not clear that things can stop existing without something exercising a causal power to annihilate them. I would even go further, because to me, a thing stopping to exist is just as inconceivable as a thing popping into existence, and just as a causal cannot really annihilate anything, a causal power cannot really make a thing exist either.

Wesley C. said...

Walter:

Well, if brute facts are possible, then a thing can easily stop existing without any cause whatsoever.

As for the idea that it's just inconceivable that things could stop existing, most people don't have such a weird intuition. If a contingent thing's existence at any moment of it's existence is clearly contingent and not necessary, it means that it's not necessary that it exists or continues to exist at any moment, therefore opening up the possibility that it could cease or fail to exist.

One can easily imagine a thing disappearing to aid one's understanding of how a thing could stop existing - precisely because if a thing stopped existing it would disappear as well.

Walter Van den Acker said...

Wesley

You could just as well say that if brute facts are possible, a thing can easily start existing without any cause whatsoever. But that is the very question: does it make sense for a thing to pop into existence or not? To me, that doesn't make sense.
If something can exist eternally without a cause or a reason it doesn't follow that a thing can start existing without a cause or a reason.

I can easily image a thing disappearing, but I can also imagine a thing appearing, but that doesn't mean it can really stop or start existing.
BTW, I am not talking about a thing changing form, about snow melting, or matter becoming energy because those examples do not involve completely going out of exsietnce.

Alexander R Pruss said...

Wesley:

1. If x is any contingent thing, then all the secondary causes of x's persistence could be active and yet x could cease to exist.
2. If all the secondary causes of x's persistence could be active and yet x would cease to exist, then when x does persist, there is an explanation of x's persistence that goes beyond the secondary causes.
3. So, if x is any contingent thing, there is an explanation of x's persistence that goes beyond the secondary causes.

I think 2 needs support. The mere fact that a cause A could fail to effect B does not seem to imply that there is some explanation of B that goes beyond A, unless one either accepts theism (in which case we get circularity) or one accepts both the PSR and the principle that if p explains q, then p entails q. But one cannot accept both the PSR and that principle, as they imply modal fatalism (that everything that is is necessary).

I also think 1 is counterintuitive, unless one independently believes there is a God who can annihilate anything at any time.

Red said...

Don't we experience things going out of existence all the time? Unless one believes in some crazy kind of monism I don't see how it could even make sense to doubt that things go out of existence. And we do talk about things going out of existence, its part of natural ordinary language so I don't see how it could be counter-intuitive.

Or at the very least even if we are not talking about substances going out of existence we its at least obvious that state of affairs do.

Alexander R Pruss said...

Sure, things do go out of existence, but normally we can point to either causes of their going out of existence (e.g., a cat goes out of existence when hit by a car), or the cessation of causes of their continuation (e.g., a plan goes out of existence when deprived of sunlight). Something going out of existence without an explanation is much more controversial.

Wesley C. said...

Alex:

I wasn't specifically making an argument that continued existence has an explanation. Rather, I was only arguing for premise 1. All it takes to establish that premise is that things could fail to exist at any moment. Even if the moment-to-moment existence of things were without explanation, it would still be true that secondary causes do not account for a thing's sheer existence per se. The dog could save the cat's life and in this sense be a secondary analogous cause of existence, but the sheer moment-to-moment existence of the cat (whether or not it has an explanation) is of a different category.

Walter:

I don't see why saying a thing could cease to exist doesn't make sense. It's easy to demonstrate that a thing could conceivably stop existing at any moment. For any contingent thing x, it's existence at any moment is contingent. Therefore, it's existence at any moment is not necessary. Therefore, it's existence at any moment could in principle fail to obtain.

IanS said...

Alex:

Can a walnut pop to a location that is already occupied? If so, what happens to the stuff that is already there? If not, the popping process somehow has to check in advance that the target location is empty. How would that work?

It would be hard to find a strictly empty place in this universe. Even in outer space, there are neutrinos, cosmic rays and interstellar gas.

These issues do not apply (at least not in the same way) to popping ex nihilo. So it is not obvious that popping a walnut into this world would be easier than popping a walnut universe ex nihilo.

Walter Van den Acker said...

Wesley

If it's easy to demonstrate, the please go ahead and demonstrate it.
That a contingent things isn't necessary is not the issue here, but your last sentence begs the question. If a thing is continegnt, then its non-existence doesn't entail a contradiction, but it does not follow that if it exists, it could go out of existence.

Wesley C. said...

Walter,

Actually, that a thing is contingent by definition implies that it really could have been otherwise. If not, then the term "contingent" is merely shorthand for "logically possible".

The idea that things can't actually stop existing is a very weird metaphysical premise. Usually God is thought of as being the sole metaphysical principle that by His very nature cannot stop existing. If contingent substances can't actually stop existing, then they are metaphysically necessary in that respect.

What you end up with is a type of weird quasi-pantheism where we have superficial change in terms of substances, but the underlying substratum is necessary.

Atno said...

Another eternal chaos scenario:

If brute facts have no probability, Robert Koons has argued we canno rule out the idea that our current conscious state has always changelessly existed from eternity. This is clearly incompatible with all our common empirical knowledge, but if it is a possibility (an eternal, contingent brute fact) then we cannot say it is improbable.

Atno said...

Another similar skeptical scenario would be this: from eternity, there has always existed a Cartesian demon who constantly feeds me false experiences and information. No probability for this demon existing.
Or, from eternity, my brain has existed in a vat, etc...

Walter Van den Acker said...

Wesley

Contingent means that there is a possible world in which a thing doesn't exist. It does not mean that there is a possiblle world in which that thing did not exist, then came into existence and then stopped existing. So, "contingent" really is shorthand for "logically possible without making a claim of necessity".

As for your second paragraph, "weird" is a subjective term. And until I have seen your demonstration that a thing could conceivably stop existing, I find the idea of some God willing things and and out of into existence while remaining completely the same much weirder.

Wesley C. said...

Walter,

First of all, I would reject the possible world language when describing contingency.

Second, if a thing's existence at any moment is contingent, then that means it could not exist at that moment. It means that a thing could exist at previous moments, but have failed to exist at that particular later moment.

This is really obvious. You really have to be stretching things in order to deny that.

And if you deny that a thing could possibly fail to exist at one moment even though it existed previously, then you end up with a really weird quasi-pantheistic metaphysics where it's metaphysically impossible for something to stop existing full stop if it actually exists (substantial change not being existential change).

That is, to say the least, a minority view, and something only some type of pantheist would accept. I take it you are not a pantheist though.

Walter Van den Acker said...

Wesley

You may reject possible world language, but it is still a fact that contingent simply means that there is no logical contradiction in the thing's existence and neither is there a logical contradiction in the thing's non-existence.

And yes, I hold to a kind of metaphysics where it's metaphysically impossible for something to stop existing full stop if it actually exists and where it is metaphysicall impossible for something to start existing full stop. Reality exists but as long as there is no contradiction in its non-existence, I think it's premature to call it necessary.

This is not a pantheistic view because it doesn't involve any sort of deity or anything god-like.

Wesley C. said...

Walter,

This is quite ironic. Most atheists usually accept the possibility and actuality of brute facts simply on the basis that they are logically possible (not contradictory) and thus metaphysically conceivable in that sense. And you are saying that the logical possibility of something ceasing to exist is not enough to accept that as an actual possibility.

As far as contingency is concerned, if we take the possible worlds talk seriously as describing what actually could be the case in some possible world (which is what it is describing), then your objection doesn't make any sense. If it's metaphysically impossible for something either to start or to cease existing, then there is no possible world where that can actually happen. It's metaphysically impossible (and therefore actually impossible) and no world could countenance such a thing.

And as far as pantheism is concerned, it's not strictly a matter of thinking everything is a deity, but generally imbuing creation with qualities that are usually ascribed only to divinity. Impossibility of not existing is such a trait. If we take this seriously, then this means that creation could not have had a beginning and cannot stop existing as a matter of metaphysical necessity. Every moment of it's existence would be necessary.

So the answer to the question of why anything exists would be that the existence of the universe is necessary......are you still sure you're an atheist?

Dagmara Lizlovs said...

I have an atheist co-worker who believes that the material and energy to create the Universe popped into existance out of nothing. If we have a total vacuum and an absolute nothing, then how could something come from it. Which requires more faith? A Creator causing energy and matter to appear or energy and matter generating themselves out of an absolute nothing or vacuum? Which of these positions takes greater faith. I must say my atheist co- worker has greater faith than I.

Atno said...

Walter,

Contingency may be that which occurs in one possible world but not in all of them. But that does not explain what contingency is or what grounds it. We can use possible worlds talk but it does not help explain what makes something possible, contingent, necessary, etc.. Aristotelians and Thomists would explain and ground contingency in real things, and in particular in features such as the distinction between act and potency and essence and existence (which in turn can lead to causal theories of possibility, such as the one Pruss defends...). And *these* explanations of contingency would imply there is no difference between something possibly not existing and something possibly not existing at t. That which is contingent is always contingent; that which has contingent existence will also have contingent "persistence"; there is no such thing as "continuing to exist", just existence at different times. Frankly I find it bizarre how anyone could suggest X somehow can fail to exist, but once it actually exists it is necessarily the case that it cannot fail to exist (from that moment onwards). You could reject this explanation of contingency, and refrain from grounding possibilities in the natures of real beings. But then how would you explain what makes something contingent? How would you ground the possibility of a contingent thing not existing? And even if someone is in principle open to brute facts, they should still be very undesirable and a last resort - brute facts count against a theory.

Walter Van den Acker said...

Wesley

There is nothing ironic about this. I do think that popping into (or out of) existence is metaphysically impossible because I believe in ex nihilo nihil fit.
But I am not aware of any conclusive arguments against the possibility of eternal brute facts, and that why I do not reject those.
I do think reality may be necessary in some way, but since I can't really prove that, I am not going to claim it.

Miguel

It's a matter of either ... or. Either something is necessary or everything is contingent. If something is necessary, its non-existence entails a contradiction, and that is what 'grounds' it.
I agree that on Thomism, my view wouldn't make any sense, but I reject Thomism for various reasons, so your argument here does not in any way convince me.
I also agree that brute facts are undesirable, but possibility is not based on desires. Moreover, I do not claim brute facts exist, I just do not want to commit to something i cannot prove. So, I leave open the possibility of brute facts.

Dagmara

I agree that energy and matter generating themselves out of an absolute nothing 'takes great faith', and that's why I reject it. Eenrgy and matter generating themselves out of a vacuum (or something), however, does not take great faith at all. It doesn't violate the principle that ex nihilo nihil fit, because the vacuum is not absolutely nothing.

Now, I really enjoyed this discussion, but I am going to bow out.

Wesley C. said...

Wesley,

It is ironic. After all, it's clearly at least logically possible for something to start or cease existing, yet the intuition ex nihilo nihil fit somehow makes you reject it as metaphysically impossible, though logically possible. In the same way, even though brute facts seem at least logically possible, theists reject it as metaphysically impossible due to the common-sensical intuition that things can't just happen for no reason at all, or PSR. (And it's not at all clear why or how ex nihilo nihil fit entails something can't start or cease to exist. After all, things aren't coming to exist from nothing, but are given being by Being itself, Who is not nothing)

As for the idea of brute facts, this contradicts your idea that the existence of the universe is metaphysically necessary. If something happens as a matter of brute fact, then it's obviously not necessary in any way; yet every moment of the universe's eternal existence is metaphysically necessary; therefore the existence of anything cannot be a brute fact. So the universe doesn't exist for no reason. So brute facts do not apply to the realm of existence.

And yes, your position obviously entails the universe is metaphysically necessary. It's a type of pantheism similar to Spinozistic rationalism, where everything is necessary (whether or not you see the universe as divinity, metaphysical necessity is an aspect of divinity, and so that's a variety of pantheism).

Wesley C. said...

Walter,

My mistake! I should have written "Walter," in the beginning, not Wesley!

Atno said...

Walter,

But you're still not explaining contingency. You have merely redescribed the necessary x contingency distinction, but we want an explanation for *why* a thing's non-existence is such as to not imply a contradiction, why something falls into the contingent category instead of the necessary one, etc. Thomism and Aristotelianism provide reasons for that. We have explanations for why something is contingent grounded in its own nature being distinct from existence; etc. You might reject their explanation, but then you have to provide your own explanation or grounding. Otherwise you'd just be relying on a furher brute fact, and that is a very bad position to be in, epistemically.

"Possibility is not based on desires" no one has implied it is. The thing is, brute facts should be a last resort. It counts against a theory if it multiplies brute facts. In this sense, brute facts are "undesirable". This is a further cost to your view which you must consider.

Alexander R Pruss said...

Ian:

I don't think there is anything really problematic about there being two things in one place. As far as we know, it is physically possible for bosons to do it. It may not be *physically* possible for some other types of particles to do it, but I don't see that it's metaphysically impossible.

Atno said...

Pruss,

I think a further problem with brute facts in general - if they have no meanigful probability - is that not only would we be incapable of ruling out bizarre scenarios (random things popping in and out of being; weird laws producing unpredictable effects; etc), but we would be going against some very strong explanatory intuitions. Consider design arguments for God, for instance. John Leslie rejects the idea that we could not make any probabilistic inferences about the universe, or that fine tuning doesn't need any explanation (either in terms of design, or a multiverse):

"So let us imagine that on measuring the strength ratio of two fundamental forces we find that the one is 11.201210020210002000021102002100 times stronger. Intrigued— for when numbers are expressed decimally you expect something other than twos, ones and zeros—a scientist tests the idea that a Designer has here left a message in Morse code: zeros for dots, ones for dashes, and twos for spaces. The test yields MADE BY GOD. Whereupon philosophers comment that this is nowise ‘contrary to chance’, ‘a defiance of probability’, since the universe cannot happen more than once, etc."

The same kind of scenario would apply if contingent brute facts have no meaningful probability simply by being brute facts. But that would be bizarre. We could imagine even more obvious ways in which the universe could exhibit design; but if the existence of the universe were due to a brute fact, we wouldn't be justified in concluding it was created by God even if all the fundamental laws (for example) include the entire Old and New Testaments in morse code, alongside prophecies and predictions that turned out to be true in the next day, etc. But that is clearly absurd. So we know something is wrong with this reasoning, and the more plausible option is that brute facts are absurd and impossible (at least if someone is convinced they could have no probability). We should be able to infer design from these facts.

This kind of scenario would hold for the whole universe, and it seems entirely general. It has the advantage that even people who reject the possibility of other scenarios (things popping into existing; things ceasing to be; weird laws; or anything else) would still be open to it. Someone could try to bite the bullet, but I think it'd be hard to deny that the imagined scenarios should allow us to rationally conclude design, or at least give us probabilistic evidence for design.

Any thoughts?

IanS said...

Alex:

It is no doubt metaphysically possible for two things to occupy the same space. But is it physically possible in this world for two macroscopic objects to occupy to same space? That is not so obvious. If it is not physically possible, it complicates your walnut-popping argument.

Alexander R Pruss said...

Ian:

Surely there is nothing physically impossible--and indeed the probability should be strictly bigger than zero--about your particles all quantum tunneling to be inside me. Of course, the result is that we'd both die.