The best talk I heard at the International Congress of Logic Methodology and Philosophy of Science in Beijing was, somewhat to my surprise, the Presidential Address by Adolf Grünbaum. I wasn’t expecting much, as the genre of Presidential Addresses by Octogenarian Philosophers is not one noted for its moments of soaring rhetoric. I recognized Grünbaum’s name as a philosopher of science, but didn’t really know anything about his work. Had I known that he has recently been specializing in critiques of theism from a scientific viewpoint (with titles like “The Poverty of Theistic Cosmology“), I might have been more optimistic.
Grünbaum addressed a famous and simple question: “Why is there something rather than nothing?” He called it the Primordial Existential Question, or PEQ for short. (Philosophers are up there with NASA officials when it comes to a weakness for acronyms.) Stated in that form, the question can be traced at least back to Leibniz in his 1697 essay “On the Ultimate Origin of Things,” although it’s been recently championed by Oxford philosopher Richard Swinburne.
The correct answer to this question is stated right off the bat in the Stanford Encyclopedia of Philosophy: “Well, why not?” But we have to dress it up to make it a bit more philosophical. First, we would only even consider this an interesting question if there were some reasonable argument in favor of nothingness over existence. As Grünbaum traces it out, Leibniz’s original claim was that nothingness was “spontaneous,” whereas an existing universe required a bit of work to achieve. Swinburne has sharpened this a bit, claiming that nothingness is uniquely “natural,” because it is necessarily simpler than any particular universe. Both of them use this sort of logic to undergird an argument for the existence of God: if nothingness is somehow more natural or likely than existence, and yet here we are, it must be because God willed it to be so.
I can’t do justice to Grünbaum’s takedown of this position, which was quite careful and well-informed. But the basic idea is straightforward enough. When we talk about things being “natural” or “spontaneous,” we do so on the basis of our experience in this world. This experience equips us with a certain notion of natural — theories are naturally if they are simple and not finely-tuned, configurations are natural if they aren’t inexplicably low-entropy.
But our experience with the world in which we actually live tells us nothing whatsoever about whether certain possible universes are “natural” or not. In particular, nothing in science, logic, or philosophy provides any evidence for the claim that simple universes are “preferred” (whatever that could possibly mean). We only have experience with one universe; there is no ensemble from which it is chosen, on which we could define a measure to quantify degrees of probability. Who is to say whether a universe described by the non-perturbative completion of superstring theory is likelier or less likely than, for example, a universe described by a Rule 110 cellular automaton?
It’s easy to get tricked into thinking that simplicity is somehow preferable. After all, Occam’s Razor exhorts us to stick to simple explanations. But that’s a way to compare different explanations that equivalently account for the same sets of facts; comparing different sets of possible underlying rules for the universe is a different kettle of fish entirely. And, to be honest, it’s true that most working physicists have a hope (or a prejudice) that the principles underlying our universe are in fact pretty simple. But that’s simply an expression of our selfish desire, not a philosophical precondition on the space of possible universes. When it comes to the actual universe, ultimately we’ll just have to take what we get.
Finally, we physicists sometimes muddy the waters by talking about “multiple universes” or “the multiverse.” These days, the vast majority of such mentions refer not to actual other universes, but to different parts of our universe, causally inaccessible from ours and perhaps governed by different low-energy laws of physics (but the same deep-down ones). In that case there may actually be an ensemble of local regions, and perhaps even some sensibly-defined measure on them. But they’re all part of one big happy universe. Comparing the single multiverse in which we live to a universe with completely different deep-down laws of physics, or with different values for such basic attributes as “existence,” is something on which string theory and cosmology are utterly silent.
Ultimately, the problem is that the question — “Why is there something rather than nothing?” — doesn’t make any sense. What kind of answer could possibly count as satisfying? What could a claim like “The most natural universe is one that doesn’t exist” possibly mean? As often happens, we are led astray by imagining that we can apply the kinds of language we use in talking about contingent pieces of the world around us to the universe as a whole. It makes sense to ask why this blog exists, rather than some other blog; but there is no external vantage point from which we can compare the relatively likelihood of different modes of existence for the universe.
So the universe exists, and we know of no good reason to be surprised by that fact. I will hereby admit that, when I was a kid (maybe about ten or twelve years old? don’t remember precisely) I actually used to worry about the Primordial Existential Question. That was when I had first started reading about physics and cosmology, and knew enough about the Big Bang to contemplate how amazing it was that we knew anything about the early universe. But then I would eventually hit upon the question of “What if they universe didn’t exist at all?”, and I would get legitimately frightened. (Some kids are scared by clowns, some by existential questions.) So in one sense, my entire career as a physical cosmologist has just been one giant defense mechanism.
Sean,
One does not need an ensemble of things in order to speak of “likeliness” of one thing or another. It depends on one’s idea of “likeliness”: the bayesians can talk about the likeliness of our universe, to them the entropy of our universe is a valid idea and not based on phase space of universe or multiverse etc.
Robert L. Kuhn wrote an article in the most recent issue of Skeptic Magazine addressing the “Why not nothing” question. Ha! just found out that its online now, you can read it here: http://www.skeptic.com/the_magazine/featured_articles/skeptic13-2_Kuhn.pdf
(.9999999999…) does not equal 1!!!!
/snark
If it looks like a question is unanswerable, even in principle, is it cheap to call it meaningless?
I think so, because the honest answer is “I don’t know.”
I think the attempt to answer the question might be pointless, but I don’t think the question itself is meaningless.
If it looks like a question is unanswerable, even in principle, is it cheap to call it meaningless?
You could replace “a question is unanswerable” with “string theory is unfalsifiable”, but some might find that objectionable 😉
That fact that a question has the power to induce existential terror in a young child is significant (ten years is awfully young for that). It’s a question that will keep coming up again and again, so if can’t be answered, at least it deserves some kind of explanation, elaboration, deconstruction, or mutation into a question that can be dealt with. Maybe this thread is a small step in that direction.
Nature abhors a “nothing”, or the absence of something defines the need for it… 😉
You could replace “a question is unanswerable” with “string theory is unfalsifiable”, but some might find that objectionable
Only because your statement is false. The multiverse is unfalsifiable, but it too can still be justified IF you could prove that it is necessary to a valid tested theory of quantum gravity, or the ToE.
There should be a time limit on that tho!
Sean, I am surprised that you didn’t bring up the issue of whether “something” versus “nothing” even makes sense apart from logical description. Seriously, you just can’t logically explain the distinction between substantive existence and logical existence, because “existence” is not a describable property except for mathematical concepts like roots of equations, which numbers are prime etc. Not that I think it really is meaningless, just that it is in strictly logical terms (I mean, you can appeal to conscious experience or some non-logical, ironically mystical distinction.) Even if you somehow can make substantive existence coherent, there’s then the issue of why what existed would be like this and not otherwise. So, the basic choices are:
A. “Existing” (in some special, substantive sense over and above logical description) is meaningless and therefore “everything exists” (modal realism, which my readers tire of, but right here it is spot-on relevant.) That creates a huge mess, with there being no expectation of our being in an orderly world. (Even if we don’t have a specific idea of measure, we can come to some conclusions about what is generally likely in crude terms, especially about some conditions being “very unlikely.”
B. If substantive existing is taking as meaningful, then it is a logically peculiar brute fact for this possible world with its properties (even given the supposed rules of variation from place to place) to “exist” and others not to (aside from the simplicity issue.)
C. There is some organizing principle etc. behind what exists and what it is like, and what does not. That can’t be just the background platonics or logic per se, as I explained.
BTW, for those who like to critique on the basis of “falsifiability:
Statements like “Things continue to exist even while not being observed” are not strictly falsifiable. If you don’t like such major dislocations, consider that the specifics of what you said to someone yesterday aren’t either, unless it was recorded etc. Also, probability claims are not falsifiable: Consider the long-term frequentist perspective. Any particular run of potentially falsifying results (10,000 heads in a row, one billion heads in a row etc. during the flipping of a coin with alleged 50/50 chances) will eventually happen, which is self-contradictory. Food for thought and humbleness.
There is no such thing as existence or non-existence, only observable reality.
There is no such thing as time or space, there are only interacting extended objects.
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Thomas: “Observable” implies observers and/or experience, or in what sense would it mean more than the tautology that what exists is what exists? Making a special deal out of the sort of activities by complex “entities” that are interacting with other things, and not just the “simple”actions by themselves? Those activities are part of the describable model universes (possible worlds) too. It is easy to imagine too that observing is not really a matter of inferring from experience, if you have been beguiled by naive realism and the sophistry of ordinary language philosophers like Ludwig Wittgenstein, Gilbert Ryle, etc. But any intelligent and candid person who plays with optical magnification, focus, distorting optical media etc, realizes that the visual scene is a representation, a mental construct, not the world out there just given before us.
Another problem with defining reality in terms of the “observable,” which cannot be taken for granted: is a field really observable, or just a way of talking about how the (pretended to be) “directly observable objects” like charges etc. behave? We know there are rules about how they behave, but what does it mean to say “fields actually exist?” This gets back to the modal realism issue, but in segmented form (ie, different categories in the universe, instead of whether the universe as a whole exists apart from logical description.)
Sean wrote:
There is no way to do away with a certain number of brute facts, if you believe that there is more than one conceivable universe (and I do).
Sure there is a way to do away with brute facts: deny the existence of any contingent facts. If every fact is a necessary one, then none of them are brute.
And that is why the question of why there is something is rather than nothing is a meaningful question: it’s really asking, why are there any contingent facts? A contingent fact is a fact that could have been otherwise, right? But if it could have been otherwise, then it is certainly meaningful to ask why isn’t it otherwise.
If, as it turns out, there are no contingent facts, however, then we have a rather elegant answer to the original question: The reason why things are the way they are, is because this is the only possible way for them to be.
Your cosmologist colleague Max Tegmark has a theory that asserts this. As does David Lewis’s Modal Realism, as was mentioned by Neil B. above.
Douglas, that’s why I wrote “if you believe that there is more than one conceivable universe (and I do).” To me it’s pretty obvious that there are contingent facts. Why couldn’t the universe be a Rule 110 automaton? And how do you know? And if every possible universe exists, that itself is a contingent fact. Certainly didn’t have to be that way.
Douglas:
I think you are confused about Modal Realism/Tegmark’s idea (which is essentially the same, perhaps more logically well-ordered, and BTW MR is really an old idea in essence. I don’t really agree with MT, but Wow was his Sci. Am. article about parallel (multiple) universes in 5/03 cool as heck – “good to read stoned.”) The idea of MR is not at all that “this” is the only logically possible way for things to be, but the polar opposite: There is every possible way for things to be, and no reason in logical principle to select some or one, and not others, with a special magic wand of substantialization, “making real” etc. Max believes that “everything” exists (in a platonic multiverse, some universes do literally have flying spaghetti monsters or any other configuration possible….) It is like the principle of sufficient reason applied to existing itself. Take another look at my previous discussion and I think you’ll at least get the point, whether you want to agree. I just can’t accept either a suspiciously singled-out logical possibility made manifest, or the mess of “everything goes, and does,” so that turned me into an abstract philosophical theologian who thinks that some management, “God only knows what”, is keeping order in some sense (not to be confused with being omnipotent etc, over instances: this is more like a high-class Deism.)
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Neil B.
Max Tegmark’s papers have convinced me but then I am only a chemist suffering from “physics envy”. I have been following them on and off right back to his original 1997 ? TOE paper.
It seems to me you either have to accept a multiverse/modal realist position or be some sort of deist/theist. Of course you have the interesting position of Max’s colleague Martin Rees (the British Astronomer Royal and President of the Royal Society) who on the one hand is a practicing Anglican (Episcopalian to you US’ians) for family and community reasons, but on the other hand is a declared atheist and who seems to use the multiverse concept in his work as part of an atheist agenda for cosmology.
Douglas
The view you falsely attribute to MT is close to the position Einstein held.
Finally as an atheist I think it really really cool that MT is managing to extract money from the Templeton Foundation.
Excelent article friends, congratulations, you have clarified a question that i have had since my childhood, thanks.
So Martin has the choice on the one hand to believe in a ‘God’, which he cannot observe, or an ensemble of other universes that cannot be observed…..
Garth
The opposite of a great truth is also a great truth – T. Mann
for example, the opposite of empty set {} is a non-empty set, such as the set of integers, or the finite sets we experience in our mundane lives.
also a lesser context can define the greater context, and vice versa. that is, each is defined by what it is not i.e. its antithesis; for example, the antithesis of quanta and spacetime manifold.
so what if our universe, or a divergent cyclical set of universes (hence non-empty set with 1:1 correspondence to integers), has a greater context of the simplest case i.e. empty set? Could this be indirectly inferred; of course without perturbing such alleged greater context? Such as if there were multiple ‘universes’.
Well you can definitely get nothing from something (just ask my broker)as well as something from nothing (just look at my baby boy) but you can’t not get nothing from nothing, though if you could, wouldn’t that be something? 😉
Finn
Again, you can’t ask the question of why not “nothing” if you have no presidence that “nothing” is even relevent.
Leibniz, in his 1697 essay “On the Ultimate Origin of Things”
What “origin of things”… ?
First, we would only even consider this an interesting question if there were some reasonable argument in favor of nothingness over existence.
What “nothingness”… ?
It is only valid to speak of something else, not “nothing”, unless you can prove that “nothing” is even relevant.
What am I missing?
Nothing.
Why do I set myself up like that… ?
… might be the best question… 🙂