Friday, May 27, 2011

JFK's assassination

Here's a theory about JFK assassination:

  1. a speedily moving bullet came into existence out of nothing for no cause at all an inch from JFK's body.
This theory is crazy. It is crazy given what we know about Oswald, but it would also have been crazy if no assassin had ever been found.

Yet this theory isn't that different from the atheist's theory of the origins of the cosmos (the sum total of all contingent existence).

And notice that it is, intuitively, easier for a speedily moving bullet to come into existence ex nihilo than for a cosmos with the low entropy and high energy of our cosmos to do so.

38 comments:

  1. Could you say what exactly the atheist would give up by claiming that the cosmos is necessary (or point me to a helpful reference)?

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  2. If tbe cosmos is necessary, are its parts necessary too?

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  3. I suppose that if the cosmos is necessary, then its parts are necessarily just as they are. I'm not confident about that judgment, though.

    It looks like your question presents the following dilemma. On the one hand, if everything in the universe is necessarily just as it is, then there is only one possible world and the usual semantics for modal logic doesn't make much sense. That seems like a high cost, but I'm no modal logician. Are there other options for making modal logic work?

    On the other hand, if the parts are not necessarily just as they are, then there is still a question about why the parts are the way that they actually are. And I suppose that that open question brings back the cosmological argument via a principle of sufficient reason or some such.

    Is that the way you see things?

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  4. Given your background in physics, I'm curious: do you think the claim that subatomic particles are (ontologically) indeterminate is consistent with traditional theism?

    After reading your post, my thinking was like this:

    "Theists endorsing indeterminacy might say that there are brute facts and God just knows them. Wait, but how can a theist accept brute facts and still endorse PSR?"

    Cheers,
    David

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  5. Is God included in the set of things that we called the "universe"?

    If not are God's actions "parts" of the universe?

    If not are the results/products/effects of God's actions "parts" of the universe?

    Etc?

    If God is a necessary being, how are things that come from God not necessary beings?

    Is that what you are asking, Jon?

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  6. The appearing bullet theory sounds better than the Oswald theory to me, but maybe I'm just too much of a conspiracy theorist!

    In any case, your exchange with Jonathan puzzles me profoundly. As far as I can see the question is whether the cosmos exists eternally not whether it exist necessarily and, at least in principle, it can exist eternally even if its parts do not, isn't it?

    As for the low entropy "initial" conditions, I've always been fascinated by the suggestion that the universe might go through cycles of higher- and lower-level entropy. Assuming the universe is a closed dynamical system (how could it not be?), Poincaré recurrence theorem would seem to require that for an eternal univers.

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  7. In any case, your exchange with Jonathan puzzles me profoundly. As far as I can see the question is whether the cosmos exists eternally not whether it exist necessarily and, at least in principle, it can exist eternally even if its parts do not, isn't it?

    I'm not sure I see that. Insofar as some naturalists accept the Big Bang as the start of the universe and time itself, it seems that Alex's question applies.

    And even if not, then the question (I take it) can be applied to the laws, etc. The PSR is far-reaching.

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  8. Crude,

    That's not necessarily the right way to think of the Big Bang, but (unless Alex is happy with that) I don't want to hijack this thread by turning it into a discussion of philosophy of cosmology.

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  9. Crude,

    And even if not, then the question (I take it) can be applied to the laws, etc. The PSR is far-reaching.

    I'm not sure I follow you there, but, personally, I believe that the so-called laws of nature are metaphysically necessary.

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  10. Gabriele:

    I think an eternal contingent universe should be seen as just as puzzling as a non-eternal contingent universe. After all, why should making the universe spatiotemporally bigger make it less puzzling? If anything, we should be more puzzled by the bigger universe.

    As for the eternal recurrence, current inflationary physics appears to imply a finite past.

    Jonathan:

    It seems that there would be nasty consequences of everything being necessarily as it is. First, this radically violates our modal intuitions. Second, current indeterministic physics ends up being incomplete. Third, free will is endangered.

    David:

    In quantum mechanics under something like the Copenhagen interpretation, the wavefunction is perfectly determinate. It just says things like: the unobserved particle in a superposition of being here and of being there. We may describe this feature of the perfectly determinate wavefunction by saying "the particle's position is indeterminate", but at the fundamental level there are no positions, just wavefunctions. And of course it's not determined (but "determined" and "determinate" differ relevantly here) which way the wavefunction will collapse if you observe the position--you might see the particle in one place or you might see the particle in the other place. But your seeing, on the Copenhagen interpretation, makes it be in one place or the other--it wasn't true before your seeing that it was there.

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  11. Gabriele:

    "but, personally, I believe that the so-called laws of nature are metaphysically necessary."

    I am guessing that the view you hold is something like an Aristotelian view that the laws are grounded in the essences of objects. If not, you can disregard what I say below.

    I am not sure that view of laws is complete. I am open to there also being something like laws that specify what sorts of things exist. For instance, there might be something like a law that says that all the material things that exist have essences that conserve mass-energy. It's not necessary that mass-energy be conserved--surely, there could be objects that don't do that--but there aren't, and it's something like a law that there aren't.

    So I am open to the idea that in addition to laws grounded in essences or powers, there are also laws in the Mill-Ramsey-Lewis sense of axioms in the best systematization of nature that do not supervene on the essences of things. However, as a theist I can solve the main problem about such laws, namely the question of the way in which Mill-Ramsey-Lewis laws are explanatory. They are explanatory because they are intended by God due to their elegance.

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  12. "I don't want to hijack this thread by turning it into a discussion of philosophy of cosmology."

    But it is a post about cosmology. :-)


    One way to see my little "argument" is along the lines of Taylor's little argument that, surely, if the universe were the size of a walnut we'd require a cause for it, and that it's bigger doesn't make it require a cause less!

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  13. Or maybe he even says that if the universe consisted of just one walnut, then, etc.

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  15. It seems to me that, if the cosmos is necessary, and if mereological atomism is true, it follows that the mereological atoms of the cosmos are necessary too.

    That is to say, all atoms would have their properties essentially, and, moreover, the cardinality of the atoms 'taken together' would be a necessary truth as well.

    Yet, a necessary cosmos might contain many contingent composites, such as tables and chairs, etc.

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  16. I was thinking that all sorts of arrangements are going to be part of the universe, too, but let's suppose it's just atoms.

    It seems we get a lot more necessities. Suppose that in the lab I choose to crash an electron and positron together to make two photons. Call these two particular photons Castor and Pollux. Then on the view, I have to say either that: (a) it was necessary that I crash this electron and positron, or (b) necessarily, if I did not crash this electron and positron, Castor and Pollux would have come into existence on some other occasion. Neither (a) nor (b) is plausible.

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  17. Alexander:

    I think an eternal contingent universe should be seen as just as puzzling as a non-eternal contingent universe. After all, why should making the universe spatiotemporally bigger make it less puzzling? If anything, we should be more puzzled by the bigger universe.

    Of course, you would agree that it's not a question of bigger. One wouldn't need to explain how the bullet came into existence if the bullet never came into existence.

    As for the eternal recurrence, current inflationary physics appears to imply a finite past.

    I only had a quick look at it from my phone but I can't see how the article you link implies that. Could you please elaborate?

    I am guessing that the view you hold is something like an Aristotelian view that the laws are grounded in the essences of objects.

    I believe that the natural fundamental properties are powers and I think you can get conservation laws for free, but I'm still not very happy with my argument for that.

    But it is a post about cosmology.

    Obviously, I meant 'physical cosmology'.

    One way to see my little "argument" is along the lines of Taylor's little argument that, surely, if the universe were the size of a walnut we'd require a cause for it, and that it's bigger doesn't make it require a cause less!

    I really can't see the cogency of this argument.

    G. J. E.:

    I'm not sure what you mean by mereological atomism, but, if I interpret you correctly, then most mereological atomists would say that there is no such thing as 'the cosmos.' In any case, I don't see why, if atomism is true and "the cosmos" is necessary, then the atoms would also be necessary. I find it even harder to understand how you take that to imply that each atom has all its properties necessarily. Am I missing something?

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  18. Gabriele,

    I just meant the thesis that every composite object is composed of simple objects. This does not exclude there being composites.

    My point was that, if the cosmos exists necessarily, then the atoms it is comprised of would have to exist necessarily as well. After all, if the atoms of the cosmos are contingent, how could one say that the cosmos itself is necessary?

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  19. I see what you meant by 'mereological atomism now'. But why can't there be, say, just one necessary simple and infinitely many contingent ones? Or why can't it be the case that all of the simples are contingent but, as a law of nature, at least one simple needs to exist at all time? (not that I take these possibilities seriously but I take we are doing abstract metaphysics here not serious metaphysic)

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  20. And I am still not clear as to why something that exists necessarily should have all of its properties necessarily.

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  21. A composite composed of one necessary simple and infinitely contingent ones is not necessary.

    For, plausibly, such a composite would not exist in the possible world that contains only the necessary simple.

    Thus, assuming a 'de re' reading of cosmos, a necessary cosmos couldn't be composed as suggested.

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  24. GJE:

    

A composite composed of one necessary simple and infinitely contingent ones is not necessary. For, plausibly, such a composite would not exist in the possible world that contains only the necessary simple. 



    As far as I can see, that's true only if you assume mereological essentialism.

    

Thus, assuming a 'de re' reading of cosmos, a necessary cosmos couldn't be composed as suggested.



    Doesn't 'the cosmos' in this context refer to the totality of what exist (maybe other than any God(s))? If so, insofar as something exists, the cosmos exist. So, the cosmos exists necessarily insofar as necessarily something exists even if nothing exists necessarily. Isn't it?

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  25. As far as I can see, that's true only if you assume mereological essentialism

    We do not have to assume such a strong thesis as mereological essentialism. I take it that composites can survive losing one or more parts as long as their intrinsic structure remains the same. For example, our body survives losing one or more skin cells, but, plausibly, it would not survive losing its organs.

    Now, I take it that a composite that is composed of one necessary simple and infinitely many contingent simples cannot survive losing all of its infinitely many contingent simples, since such a loss would change its intrinsic structure.

    Doesn't 'the cosmos' in this context refer to the totality of what exist (maybe other than any God(s))? If so, insofar as something exists, the cosmos exist. So, the cosmos exists necessarily insofar as necessarily something exists even if nothing exists necessarily. Isn't it?

    You seem to pursue a 'de dicto' reading of the word 'cosmos'. But, as mentioned, I'm assuming a 'de re' reading of that word.

    If we assume a 'de re' reading of 'cosmos', our cosmos could surely be a contingent object, even if something exists in each and every possible world.

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  26. You are right about mereological essentialism being too strong (I should have worded that more carefully), but my general point stands though. I took issue with assuming that the necessity of the whole cosmos implies the necessity of (all of) its simple parts (and the necessity of their properties, but I assume you no longer wish to defend that claim). Now you seem to want to defend something weaker, but I'm still not sure I see how.
    For example, if you assume the view of persistence for composites you seem to assume, why couldn't all simples be contingent but the structure necessary and the universe undergo a gradual replacement of all the simples while retaining its structure? I just think your initial stronger thesis and the weaker one you seem to be defending now rely on too many hidden and questionable assumptions.

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  27. [W]hy couldn't all simples be contingent but the structure necessary and the universe undergo a gradual replacement of all the simples while retaining its structure?

    Such a construal implies (gradual) change and hence (cosmic) time.

    Now, if you agree that current physics implies a finite past of the cosmos, it follows that your cosmos must have an initial state.

    Following your construal, this initial state consists of some collection of contingent simples.

    But then, why does the initial state consists of *these* simples instead of some other collection of contingent simples?

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  28. Gabriele:

    The paper is usually taken to show that the past timeline cannot be extended infinitely.

    If cosmoi aren't mereological sums, what are they? They don't have to have any kind of organic unity.

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  29. GJE:

    Now, if you agree that current physics implies a finite past of the cosmos, it follows that your cosmos must have an initial state.

    As I already said, no, I don't agree. And I seem to be in good company. There is people that know much more physics than me (or, I bet, any other reader of this blog) that don't agree with that either (Roger Penrose is perhaps the most famous of them).

    Alexander:

    As far as I can see, the authors of the paper are being quite cautious about the implications of their results for cyclic cosmologies and, anyway, as I said above, cyclic cosmologies seem to be still considered a live option by many working physicists.

    If cosmoi aren't mereological sums, what are they? They don't have to have any kind of organic unity.

    I'm not sure why you are asking that, but my considered answer would be long. Anyway, yes, if composition ever occured, the cosmos would a mereological sum of parts.

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  31. "With the proof now in place, cosmologists can no longer hide behind the possibility of a past-eternal universe. There is no escape: they have to face the problem of a cosmic beginning"

    (Many Worlds in One, Vilenkin, p. 176)

    Vilenkin is one of the authors of the paper cited by Pruss. In the quote above Vilenkin refers to that paper.

    (Note: quote obtained from web)

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  32. Gabriele:

    In addition to my previous post, which was directed to yourself, I believe your construal is not an example of a necessary cosmos at all, even if we would assume an infinite past.

    Let me briefly explain. Your construal was:

    [W]hy couldn't all simples be contingent but the structure necessary and the universe undergo a gradual replacement of all the simples while retaining its structure?

    Now, on my view, persistence of structure of a composite is a necessary condition for the persistence of the composite itself.

    But, this does not entail at all that persistence of structure is also a sufficient condition for the persistence of composites.

    For example, if your shoes would change into ice, than I take it that your shoes have not survived this change, even if the structure has remained fully intact.

    Therefore, in your example, even if the structure of the universe would be necessary, it does not follow that the universe itself (being the composite, not the structure) is necessary.

    For, plausibly, the actual world's universe does not exist in some other possible world which contains an entirely different collection of contingent simples at any given time.

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  33. GJE:

    I don't think I can do much but restate what I already said:

    a) Cyclical or infinite cosmologists are considered a live option by many working physicists.

    b) I think your initial stronger claim relied on way too many questionable assumptions and, as far as I can see, your weaker claims still do.

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  34. Of course I meant 'cosmologies' not 'cosmologists'! Although it would be cool to meet a cyclical cosmologist :-)

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  35. Gabriele:

    Well, if universes are mereological sums, then the necessity of the universe's existence entails the necessity of the existence of the universe's parts, and the latter claim is absurd. :-)

    My ontology doesn't actually include bullets or universes. However, I think they exist "virtually"--i.e., sentences that say things like "There is a universe" are true, but they do not express a quantified proposition--and one can still ask explanatory questions in that context.

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  36. My feeling is that the natural course of this conversation has run, so unless something significantly new is to be said, it might be good to say no more.

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  37. Atheism does not say anything about if anything existed before the universe or not. Atheism is simply non-belief in any deities.

    You are making yourself sound like a creationist...

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