A good question!
Or is it?
I’ve talked before about the issue of why the universe exists at all (1, 2), but now I’ve had the opportunity to do a relatively careful job with it, courtesy of Eleanor Knox and Alastair Wilson. They are editing an upcoming volume, the Routledge Companion to the Philosophy of Physics, and asked me to contribute a chapter on this topic. Final edits aren’t done yet, but I’ve decided to put the draft on the arxiv:
Why Is There Something, Rather Than Nothing?
Sean M. CarrollIt seems natural to ask why the universe exists at all. Modern physics suggests that the universe can exist all by itself as a self-contained system, without anything external to create or sustain it. But there might not be an absolute answer to why it exists. I argue that any attempt to account for the existence of something rather than nothing must ultimately bottom out in a set of brute facts; the universe simply is, without ultimate cause or explanation.
As you can see, my basic tack hasn’t changed: this kind of question might be the kind of thing that doesn’t have a sensible answer. In our everyday lives, it makes sense to ask “why” this or that event occurs, but such questions have answers only because they are embedded in a larger explanatory context. In particular, because the world of our everyday experience is an emergent approximation with an extremely strong arrow of time, such that we can safely associate “causes” with subsequent “effects.” The universe, considered as all of reality (i.e. let’s include the multiverse, if any), isn’t like that. The right question to ask isn’t “Why did this happen?”, but “Could this have happened in accordance with the laws of physics?” As far as the universe and our current knowledge of the laws of physics is concerned, the answer is a resounding “Yes.” The demand for something more — a reason why the universe exists at all — is a relic piece of metaphysical baggage we would be better off to discard.
This perspective gets pushback from two different sides. On the one hand we have theists, who believe that they can answer why the universe exists, and the answer is God. As we all know, this raises the question of why God exists; but aha, say the theists, that’s different, because God necessarily exists, unlike the universe which could plausibly have not. The problem with that is that nothing exists necessarily, so the move is pretty obviously a cheat. I didn’t have a lot of room in the paper to discuss this in detail (in what after all was meant as a contribution to a volume on the philosophy of physics, not the philosophy of religion), but the basic idea is there. Whether or not you want to invoke God, you will be left with certain features of reality that have to be explained by “and that’s just the way it is.” (Theism could possibly offer a better account of the nature of reality than naturalism — that’s a different question — but it doesn’t let you wiggle out of positing some brute facts about what exists.)
The other side are those scientists who think that modern physics explains why the universe exists. It doesn’t! One purported answer — “because Nothing is unstable” — was never even supposed to explain why the universe exists; it was suggested by Frank Wilczek as a way of explaining why there is more matter than antimatter. But any such line of reasoning has to start by assuming a certain set of laws of physics in the first place. Why is there even a universe that obeys those laws? This, I argue, is not a question to which science is ever going to provide a snappy and convincing answer. The right response is “that’s just the way things are.” It’s up to us as a species to cultivate the intellectual maturity to accept that some questions don’t have the kinds of answers that are designed to make us feel satisfied.
Why is there something rather than nothing?
Suppose there were nothing. Then there would be no laws because laws are something. If there were no laws, then everything would be permitted. If everything were permitted, then nothing would be forbidden. So if there were nothing, nothing would be forbidden. Thus nothing forbids itself. Therefore, there must be something. QED.
Jeff Jones says: “Another way of articulating this objection is to say that even though causality applies to the known world, it does not necessarily apply to the universe writ large. Concisely put, it is unwise to draw conclusions from an extrapolation of causality beyond our experience.”
But in fact, astronomers make such applications all the time about the stars and galaxies, and exoplanets far from us. That is, they extrapolate from known causes here locally to things distantly To take Jeff’s view is to limit ones ability to explain to the very local area, perhaps even less than the solar system.
So if there were nothing, nothing would be forbidden.
No. If there were nothing, everything would be forbidden.
I personally like the “nothing is unstable” answer in this sense: if there is nothing there are no laws (laws are something) so there is nothing to prevent nothingness from separating into something and anti-something, with laws and anti-laws. I don’t claim this is mathematically compelling as an answer, just that those who claim “something can’t come from nothing” are trying to impose a law on nothingness.
I do however personally apply Dr. Carroll’s argument to subjective experiences, such as the scent of a rose. Why don’t the chemicals of a rose’s scent smell like the scent of an orange, and vice-versa? That’s just the way those chemicals happen to smell to our sense organs in this universe. (The same is true for the feeling of consciousness. In order to exist as an experience it has to feel like something and given our brains and nervous systems that’s the way it feels.)
In this universe, DNA life can exist in an insignificant fraction of its volume for a cosmically insignificant period of time. We happen to occupy part of that volume during that period (as we would have to), and some of us (not I), ignoring the vastness of uninhabitable space and time, conclude the whole universe was made for us.
What a great article Sean, thanks for sharing it. And what a fantastic blog also. Have you considered the late E.J. Lowe’s (amongst other philosophers) notion of metaphysical categories, when it comes to something rather than nothing?
I anticipate this paper will be more physics than metaphysics, but wanted to comment on the post’s remark about theism. The most convincing argument for theism I have encountered, indeed the one I subscribe to, is a variant of that put forward by the philosopher-theologian Diogenes Allen.
First, there is the admission that there is no apparent reason why science cannot explain everything that we humans can understand about the physical universe. I dig the idea that “Why the universe?” may simply not be a sensical question to pose when it comes to science. In Allen’s formulation, questions like “Why the universe?” may prompt the thought that there is a “reason” for all this, for which there are two options: there is a God, or there isn’t a God. There are no physical indicators for God, beyond the fact that we are prompted to consider the existence of God, and there is no real good reason why science should be expected to discover those indicators in the future (not impossible, but unlikely).
The only ways we know about God are through various religious revelations, which are themselves the products of human minds (emergent products of the physical universe.) Contrary to the claims of fundamentalists, these do not provide a coherent view of the physical universe so much as they give a sense of human significance and meaning–a frame of reference whereby people and societies can figure out how to live. Many of these contain spurious ideas, but others, as time-tested, complex products of evolution, endure. Me, I subscribe to the idea of a kind of Spinozan pantheistic/panentheistic spirit, of indeterminate posture towards individual human longings and suffering–the cosmos becoming aware of itself. We are playing a type of language game not about nature and its properties, but about “spiritual” significance; logic, though useful in conveying arguments about this realm, is not going to make you believe (it’s called “faith,” after all). You either believe or you don’t. Another kind of “brute” reality, in a sense.
Insofar as proponents of naturalism would propose that science says something about how we ought to live, they venture into the realm of religion and philosophy, a type of Scientism (as much as everyone evidently hates the “separate magisteria” argument, I’m not convinced it is wrong.) There is nothing wrong with Scientism, necessarily, except that historical instances of applying science to this realm haven’t always ended well (because of the provisional, self-correcting nature of science as an investigative tool).
The one curious thing I have with some atheists is this idea that the human desire for spiritual sustenance is somehow an illusion. Just because we can define hunger as a function of metabolism does not make hunger any less real–the same thing goes for our evolved desire for larger meaning, that mystical impulse. If there’s nothing provided to satiate it, it will find something.
Should we be asking the question why or how? How does the universe exist and then I suppose you can explain this by using the known laws of physics without a need for a creator.
There are questions we cannot (yet) answer because they are difficult, and there are questions we cannot answer because they don’t make sense/don’t have answers. To avoid begging the question, any answer to the question “why is there something rather than nothing” cannot invoke anything that’s something rather than nothing (i.e. the kind of thing we were supposed to explain). So the question is: Can there be a sensible answer that doesn’t invoke something? As Sean points out, appealing to pure logic is not going to do the trick, since there is no contradiction involved in imagining the absence of anything at all.
It is very difficult to define a containment when you are contained within. Ones perception is limited to ones location relative to the whole of exstence.
Apologists such as William Lane Craig for example try to argue–in reversing the causal chain of all events to the very beginning–by stating that the first cause behind the existence of the universe is a transcendental cause. This cause would be some divine volition or intension from God I’m presuming. But the concept of causation in a physical sense as it relates to the universe is entirely different from Craig’s transcendental cause. Craig simply tacks this divine causal link onto the supposed creation of the universe; it is never defined. So there seems to be a logical problem with an argument such as; ‘transcendental (divine volition) causes physical effect (the universe).
A further problem is that believers assume there was nothing before this transcendental act. The idea that the universe is one of an infinite number of past cycles or is one universe out of an endless number of other universes as in the multiverse, are automatically discounted.
Thank you for this article. I find your question rather good! There is an alternative hypothesis to theism proposed here: https://aeon.co/essays/cosmopsychism-explains-why-the-universe-is-fine-tuned-for-life
Quite interesting, giving up the “why” ( the meaning of why is there something ) exemplifies well Noah Hariri’s idea ( Homo Deus) of modern contract: we traded the meaning against the power;
According to Hariri, we cannot have both: as long as we want to have the extensive benefits of a techno-scientific society, the metaphysical layer and related questions are a burden, go against the efficiency of the “how”.
On another hand, it becomes obvious that in order to answer your question, we cannot avoid the question of consciousness.
The hard question of consciousness seems to be intimately linked to our own existence, it’s the new limit and “far west” for science.
Yes, the wrong question. Asking why assumes a reason, which implies a purpose. The universe has no purpose, no meaning. The right question is, “Why are we here asking that question?” The answer is that it was not enough that the universe have no meaning. In order to complete the meaninglessness of the universe, the universe had to be aware of its meaninglessness. So it evolved a part of itself that was aware and could know and understand that the universe is meaningless.
This is a very interesting area, thank you for your contributions Sean. Might I add, perhaps another question to ask is ‘What is existence?’
Does the universe ‘exist’ to the insentient mind? How is ‘existence’ defined for a bumble bee, or a whale?
And does anything really ‘exist’ if there is nothing to contemplate it’s existence?
If the universe ‘exists’ only because it can be perceived, then perhaps it exists only to be perceived, and its perceived scale (time & space, incl beginning) are directly correlated to the capacities of the sentience perceiving it.
Sean, I enjoyed reading your post and paper. Quite a challenge to summarize the topic in 15-pages (while Krauss had an entire book to tackle the question). I concur on the need to cultivate intellectual maturity regarding bygone metaphysics. No gigantic turtles, eh.
So, regarding perspectives on this question, what’s changed in the last 50 years? 100 years or more? Your paper provides a backstory. “The general trend of scientific discovery over the last few centuries has been to explain disparate complex phenomena in terms of comparatively simple and powerful frameworks.” [p. 11] “As our knowledge of the universe improves, questions that once seemed urgent can become un-asked, as we realize that the context in which they were posed was not appropriate.” [p. 15]
I like the overview on pages 4 – 5 of your paper. Also, a reminder on page 10 about Leibniz’s Principle of Sufficient Reason: “Once we think of the laws of nature as describing patterns rather than causal forces, and the notion of cause and effect as being appropriate to higher-level emergent descriptions of the world rather than the fundamental level, the PSR loses its luster.” Or, as Neil deGrasse Tyson put it, “The universe is under no obligation to make sense to you.” Or whether nothing is more natural than something [p. 13]. Or nothingness is a coherent idea [p. 14].
I revisited this question last year when I read Krauss’ book A Universe from Nothing: Why There Is Something Rather than Nothing; and was interested in comparing your perspective or characterization (cf. The Big Picture: On the Origins of Life, Meaning, and the Universe Itself). Krauss sets the question in the context of a class of questions which are really “how” questions. Hence, positing the “nothing is unstable” answer (Chapter 10).
Personally, I’d like to see a broader interdisciplinary framework for the question. More inclusive than a general religion and science divide, theism and naturalism. Interdisciplinary sciences of all kinds. Certainly at Caltech that’s one dramatic change in the last 50 years — all kinds of interdisciplinary centers and titles.
The context that we have grown out of the universe (rather than come into or been placed into it) — that we are an emergent organism rather than a zero-day fully realized creature — makes a difference. Perhaps the question may continue to move us away from arbitrary habits and ways of thinking, especially those which place us at the center of the universe. So, the question may be meaningful rather than “good” or meaningless. Or, as you wrote, help us to be wary of ingrained “intuitive and metaphorical reasoning.” [p. 13]
“But the concept of causation in a physical sense as it relates to the universe is entirely different from Craig’s transcendental cause. Craig simply tacks this divine causal link onto the supposed creation of the universe; it is never defined. So there seems to be a logical problem with an argument such as; ‘transcendental (divine volition) causes physical effect (the universe).
A further problem is that believers assume there was nothing before this transcendental act. The idea that the universe is one of an infinite number of past cycles or is one universe out of an endless number of other universes as in the multiverse, are automatically discounted.”
Transcendant volition causes physical effect all the time. Our minds (a sort of transcendent thing) cause physical effects every day.
Infinite cycles fail because of entropy. Each cycle cannot reach the same stage as the previous, so they eventually collapse.
The multiverse is inaccessible so cannot be observed. it is thus impossible to determine whether it or they exist. God is just as valid a postulate as a multiverse, and is observable by the fine tuning of this one, to me a more reasonable postulate because of mind.
Why the assumption that the universe came into being ex nihilo?
Our only experience is that stuff exists. Why imagine it was ever the case that no stuff existed?
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Look at the state of scientific knowledge 2000 years ago. If you were to talk to a scientist from 2000 years ago, you’d say “keep up the good work, but, wow, you have no idea….” and “worrying about how many angels it takes to push the sun around the earth” is, well, the wrong question. I can’t kick the feeling that a scientist 2000 years in the future would say the same to us, particularly as regards some of the metaphysical ideas that are being batted around.
I don’t think humans have an innate hunger for religious meaning – but many of us have a hunger for control of our environment, and if unable to accomplish this personally, will postulate deities who could be urged to intervene in the environment on our behalf, on the grounds that it couldn’t hurt and might help. No one denies we have evolutionary urges, but the meanings of those urges can be mis-interpreted.
The basic answer to fine-tuning, as Dr. Sabine Hossenfelder has pointed out, is “compared to what?” Until a concrete mechanism for such tuning is shown to exist there is no basis for determining our universe is or isn’t fine-tuned. Neither the god nor multiverse hypotheses provides any specified tuning mechanism. “Let there be a universe” is not a mechanism, nor is waving a wand and saying “abracadabra” – magicians pull their rabbits from hats by specific mechanisms which obey physical laws.
(It may have seemed to our ancestors that some events, such as moving our limbs, occur by sheer will, but we know better now – we know the physical mechanisms by which muscles work, and can build and program machines to make similar motions.)
The rational for assuming fine-tuning seems to be that DNA-life is special, and the huge (possibly infinite) number of things that could exist in other universes with different physical laws are not. That seems an arrogant and not well-justified assumption to me. Even with that assumption, it has been shown that DNA-life is theoretically possible in a number of different universes with different laws, such as (if I recall correctly) no weak nuclear force.
In about 5 billion years, the Sun will grow to cover the Earth’s orbit and the only so-far-known, natural habitat for DNA-life will cease to exist. I expect the universe will continue regardless, and for a much longer time. Even in the current, favorable conditions, the case that the universe is fine-tuned for bacteria is much stronger than the case that it is fine-tuned for humans. (The mass of all bacteria on Earth outweighs the masses of all other creatures combined, by a factor of ten.)
Sean Carroll,
I agree with you that there is a level beyond which “why” will never be answered. Personally, I think this has little to do with the existence or non-existence of a god. It might have a great deal to do with the form a god would necessarily take, but that isn’t really relevant here.
I spent most of my life contemplating “something” separated by “nothing”. The crux to solving the most fundamental lies in “nothing” rather than in “something”. At the lowest level different laws of physic apply. These are the two major reasons that scientists have been unsuccessful in determining the most fundamental building block for our universe and everything in it.
Science doesn’t need to provide a snappy and convincing answer. It already exists. As you once pointed out there is so much garbage out there that the real answer could just be buried.
I know these comments sound like a wannabe person making them. That’s about as far from the truth as you can get. These comments are made by a person who simply wants to get the burden of knowledge off of his back. It should be possible to get at least one person to listen long enough to understand. I get why people don’t listen, but it doesn’t make it any less frustrating.
If at some point you decide to gamble and throw me a line, I would appreciate it more than you likely would understand. What you can’t know is how much you would appreciate it as well. The answer is quite amazing; and, it is all physical with no magic. This is a tool that will enable physicists such as yourself to make even more incredible advances then they have already.
It answers very specifically how gravity operates from its very beginning. It answers what the structure of the electron is. It answers what a likely structure of a quark is. It even has features that someone well-versed in quantum physics could likely use. Something similar to MOND gravity is indicated.
All I want to do is pass this ball to someone who can use it so that it won’t be lost. The likelihood of finding this in the next century is quite slim. Frankly, I wish it didn’t work. Then I wouldn’t have to be begging for someone to listen to what will be the most amazing story they have ever heard.
I have a website, but this is not something that can be understood very well without talking through the story. There are too many concepts that are foreign to our usual experiences.
Thanks for listening.
Richard
What is the reasoning behind the claim that nothing exists necessarily?
And doesn’t the claim itself constitute a claim of metaphysical necessity, is it asserts that necessarily there is nothing that exists necessarily?
I think Leibniz get sold a little short here. His point was that if there is a reason for everything then something, at least, must be its own reason.
The converse is that if something is not its own reason, then something, at least, is the case without any why or how.
Whilst the idea that our knowledge of the universe must terminate in “that is just the way it is” seems plausible, it does run into the problem that then any conceivable configuration of anything would have been equally likely to be the fundamental substance of reality. There would then be no objective way of preferring any one candidate fundamental substance over any other, so the fundamental substance could just as well have been a dead cat or a leprechaun or anything else at all.
Generally in science things are explained in terms of their constituent parts and I guess many of us have the intuition that the fundamental basis of reality must be something simple (the final set of parts), but not so simple that it can not account for our observations. But if the fundamental substance really is just a “brute fact” then we have no basis for this kind of reductionism and the floodgates are open to any kind of mysticism.
This sounds like late 19th century physics when we thought we had a handle on all the facts. They only had a few minor mysteries to clear up, and those could be trusted to future generations. Any chance that any of those brute facts could be an “emergent approximation” of something more fundamental? I mean, a fact is only a fact in the context of the present, right?
I think you are too quick to dismiss the modal realism/MUH answer. You acknowledge the difficulty in formulating the probability of any given universe, which I agree with. But you then assume, without justification, that our universe is improbable in whatever the correct formulation is. In the absense of such a formula, I don’t see any particular reason to doubt that a “typical” possible universe looks like ours.
You say that most observers would find themselves in smaller universes, but why? In the space of possible universes, are smaller universes more numerous than big ones? It seems like the opposite would be true. Furthermore, big universes presumably have many more observers than small ones. Our universe could be nearly saturated with observers, for all we know. So, finding ourselves in an enormous universe, surrounded by other observers, doesn’t seem particularly strange.
The Boltzmann Brain comparison is invalid. That thought experiment considers the number of Boltzmann vs Darwinnian brains *within a single universe*, and argues that the laws of physics must necessarily favor the latter. If the same reasoning is applicable to possible universes, then it only says that Darwinnian brains must be more numerous in the space of all possible universes, which seems entirely plausible to me.
I actually find this sort of anthropic reasoning highly suspect. I am skeptical that enumerating possible universes, or enumerating observers within a universe, are sensible concepts. But I direct my skepticism at the anthropic reasoning, rather than modal realism. The ontological equality of possible universes seems inescapable to me, even if I have no idea what a typical universe looks like.
What can one mean by the absolute negation of the term nothing?
“I am that I am ” – There is a material difference between persistence and existence
I persist that I exist.
the term “Nothing” is giving and will give way to the term “Void”
Chemistry uses the term inert.
Software uses the term void – requiring tacit change.
The void is pandimentionally (Sp?) omnipresent.
The void is persistence and provides the capacity for existence.
Our universe exists suspended within the void.
The flesh of God