Monday, March 26, 2012

Ex nihilo ... something something

Lawrence Krauss has recently published A Universe from Nothing: Why There Is Something Rather Than Nothing wherein he seeks to explain the origin of the universe in purely physicalist, specifically quantum physicalist, terms. Bill Vallicella has berated Krauss for his nonsensical metaphysical musings wrapped up in the garb of scence before and will soon begin reading Universe from Nothing (he will check it out from a library, not wanting to grant it the dignity of actually purchasing it). But he also points to this interesting critique in the New York Times of Krauss's book from which I quote liberally:

What on earth, then, can Krauss have been thinking? Well, there is, as it happens, an interesting difference between relativistic quantum field theories and every previous serious candidate for a fundamental physical theory of the world. Every previous such theory counted material particles among the concrete, fundamental, eternally persisting elementary physical stuff of the world — and relativistic quantum field theories, interestingly and emphatically and unprecedentedly, do not. According to relativistic quantum field theories, particles are to be understood, rather, as specific arrangements of the fields. Certain ­arrangements of the fields, for instance, correspond to there being 14 particles in the universe, and certain other arrangements correspond to there being 276 particles, and certain other arrangements correspond to there being an infinite number of particles, and certain other arrangements correspond to there being no particles at all. And those last arrangements are referred to, in the jargon of quantum field theories, for obvious reasons, as “vacuum” states. Krauss seems to be thinking that these vacuum states amount to the relativistic-­quantum-field-theoretical version of there not being any physical stuff at all. And he has an argument — or thinks he does — that the laws of relativistic quantum field theories entail that vacuum states are unstable. And that, in a nutshell, is the account he proposes of why there should be something rather than nothing.

But that’s just not right. Relativistic-quantum-field-theoretical vacuum states — no less than giraffes or refrigerators or solar systems — are particular arrangements of elementary physical stuff. The true relativistic-quantum-field-­theoretical equivalent to there not being any physical stuff at all isn’t this or that particular arrangement of the fields — what it is (obviously, and ineluctably, and on the contrary) is the simple absence of the fields! The fact that some arrangements of fields happen to correspond to the existence of particles and some don’t is not a whit more mysterious than the fact that some of the possible arrangements of my fingers happen to correspond to the existence of a fist and some don’t. And the fact that particles can pop in and out of existence, over time, as those fields rearrange themselves, is not a whit more mysterious than the fact that fists can pop in and out of existence, over time, as my fingers rearrange themselves. And none of these poppings — if you look at them aright — amount to anything even remotely in the neighborhood of a creation from nothing.

Krauss, mind you, has heard this kind of talk before, and it makes him crazy. A century ago, it seems to him, nobody would have made so much as a peep about referring to a stretch of space without any material particles in it as “nothing.” And now that he and his colleagues think they have a way of showing how everything there is could imaginably have emerged from a stretch of space like that, the nut cases are moving the goal posts. He complains that “some philosophers and many theologians define and redefine ‘nothing’ as not being any of the versions of nothing that scientists currently describe,” and that “now, I am told by religious critics that I cannot refer to empty space as ‘nothing,’ but rather as a ‘quantum vacuum,’ to distinguish it from the philosopher’s or theologian’s idealized ‘nothing,’ ” and he does a good deal of railing about “the intellectual bankruptcy of much of theology and some of modern philosophy.” But all there is to say about this, as far as I can see, is that Krauss is dead wrong and his religious and philosophical critics are absolutely right. Who cares what we would or would not have made a peep about a hundred years ago? We were wrong a hundred years ago. We know more now. And if what we formerly took for nothing turns out, on closer examination, to have the makings of protons and neutrons and tables and chairs and planets and solar systems and galaxies and universes in it, then it wasn’t nothing, and it couldn’t have been nothing, in the first place. And the history of science — if we understand it correctly — gives us no hint of how it might be possible to imagine otherwise.

Perhaps my ignorance of quantum physics allows me to feel greater awe at the mystery of particles popping into existence than the reviewer's fist when he rearranges his fingers, but I still get the point. I have often heard that physicists have five different definitions of "nothing". Krauss, if his critic is right, seems to be saying that we can have creation from nothing in one (trivial) sense, and if we insist on asking if we can have creation from nothing in a stronger (untrivial) sense, well just shut up.

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Wednesday, March 14, 2012

It's better to remain silent and be thought a fool

then open your mouth in front of a scholar with the cameras rolling and remove all doubt.

Update (17 March): The full video can be seen here. The other gentleman in the video (not the one who asks the question about Osiris) is Jason Danner and the venue is the University of Central Florida. To see earlier posts I've written comparing Jesus to pagan mythology, including Osiris, see here and here.

Update (22 March): Another post I've written on this topic that I neglected to link to is here. A post where I quote Ben Witherington on the uniqueness of the virgin birth is here, and is interesting in part for the comments.

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Sunday, March 11, 2012

Skepticism and Agrippa's Trilemma

Most forms of global skepticism, skepticism about everything, are only hypothetical or methodological. We are not asked to actually withhold belief in everything, we are merely being told that for all we know we may be, e.g., brains in vats being stimulated to think there is an external world. The reason this is just hypothetical is that we are given no reason to think this is actually the case, it's just that the skeptical scenario takes away any reason we could have for thinking it is not the case. Any evidence we could have, any test we could construct to make sure that the world we experience really exists, is just as readily explained by the skeptical theory. (Of course, this is controversial: Hilary Putnam has argued, brilliantly, that on a linguistic-externalist view our words obtain their meaning by virtue of their relation to their object in the world. So our word "vat" means something because there are vats in the external world. But then in order for the brains-in-vats skeptical scenario to be correct, it has to be based on an actually experienced external world, which of course contradicts the scenario.)

In contrast, real skepticism gives you a positive reason for disbelieving, or at least withholding belief in, everything. Plantinga's skepticism is an example of this, but he provides an escape clause: one can always deny naturalism and avoid the skepticism. Perhaps the best example of real skepticism is Agrippa's Trilemma: the question asked is, how is any belief justified? and there are only three ultimate answers we can give. First, we could say that it's justified by another belief, which is justified by another belief, which is justified by another belief... and this chain goes on to infinity. So it's a case of infinite reference. Second, we could say the belief is justified by another belief, which is justified by another belief, which is justified by another belief ... which is justified by the first belief. This is a case of circular reference. Third, you could say the belief is justified by another belief which is justified by another belief ... and that belief requires no justification. This is a case of foundational reference, i.e., it refers to a belief that functions as a foundation.

So what's the problem with infinite reference? Generally, philosophers point to infinite regresses as refutations of positions, but what exactly is the problem with it here? Roughly, the first belief is alleged to derive its justification from another belief, which derives its justification from another, etc. In other words, each step in the chain only has derivative justification. But without some source outside the system to input justification into it, no step will have any. It's like some of the cosmological arguments: imagine you have an infinite number of freight cars connected to each other and ask how they are moving. The first is moving because it's being pulled by the one in front of it, which is being pulled by the one in front of it, etc. But if the chain of cars goes on to infinity then why are the cars moving at all rather than just standing still? It doesn't matter how many cars you add to the chain, without some source of motion, they're not going to move. The only philosopher I know of who defends infinitism is Peter Klein in his "Human Knowledge and the Infinite Regress of Reasons", Philosophical Perspectives 13 (1999): 297-325, "When Infinite Regresses Are Not Vicious", Philosophy and Phenomenological Research 66 (2003): 718-29, and elsewhere.

What's the problem with circular reference? Essentially, it's the same problem: each step in the process is justified in virtue of its relation to the previous step, that is, it has derivative justification. Circling back to a step already referred to in the process does not somehow bring the needed justification into the picture. As Victor Reppert writes, "Circularity is the epistemic equivalent of counterfeiting" ("Eliminative Materialism, Cognitive Suicide, and Begging the Question", Metaphilosophy 23 [1992]: 386), since it gives the illusion of providing a source of justification without doing so. Nevertheless, circular reference is vastly more popular a position than infinite reference, in the form of coherentism. As far as I can tell it's still the minority view, but it's defended by many of the top philosophers around: Keith Lehrer, Nicholas Rescher, the early Laurence BonJour, Brand Blanshard, names could be multiplied. These are some of the smartest people of the last century, so coherentism cannot be dismissed without interacting with their writings.

(Another interesting claim that I've read about but have not read any actual proponents of is that a belief does not only derive justification from another belief but from the actual derivation process. So even if the beliefs themselves have no original justification, if you have enough steps involved, you will eventually build up enough justification that the beliefs will become justified. This could potentially rescue both infinite and circular reference.)

What's the problem with foundational reference? Historically, foundationalism has been the near-universal position among epistemologists, and as far as I can tell, is still the majority view today. Some beliefs simply don't need justification, or they carry their justification in themselves, they are self-justifying. The problem here is dogmatism. To say that some beliefs are the ground level, to say that some beliefs don't need to be justified by something else is to say that we don't need to question them, we don't need to verify them. But virtually every class of belief that has been proposed for this position has been challenged precisely because they can be. We need to have a reason for a belief and to continue believing in the absence of a reason is mere dogmatism. Again, most epistemologists would disagree with this, they would say that there are some foundational beliefs and that not having a reason for a belief does not make it irrational or unacceptable in this case. Some, such as Plantinga, seek to escape the charge of dogmatism by making these beliefs defeatable: they can be questioned, they can be challenged, they are just innocent until proven guilty.

So Agrippa's Trilemma says there are three options -- infinitism, coherentism, and foundationalism -- and none of these are acceptable. Therefore, we have a reason to reject each one, and therefore to reject the possibility of having any knowledge whatsoever. Thus, we are left with actual skepticism, not hypothetical or methdological skepticism. The only alternative is to do what virtually all epistemologists have done: accept one of three options.

(cross-posted at Agent Intellect)

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