Perhaps the ultimate why question: Why is there something rather than nothing?
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.
It 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.
Chapter 25 “Why Does the Universe Exist?” of Carroll’s book has more on the topic, in particular addressing the “conviction that the existence of the universe demands some kind of explanation.” He notes that “just because these questions are common, it doesn’t mean they’re the right ones to ask.” And brute fact.
There may be answers to these questions, either in naturalism or in theism. Or we may have to live with simply accepting the universe the way it is. What we can’t do is demand explanations that the universe may not be able give us.
Krauss wrote an entire book which tackles the question.
So, regarding perspectives on this question, what’s changed in the last 50 years? 100 years or more? Carroll’s 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 concur on his point for the need to cultivate intellectual maturity regarding bygone metaphysics.1 No gigantic turtles, eh.2
I like the overview of possible answers on pages 4 – 5 of his paper: creation, metaverse, principle, coherence, brute fact. 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 Carroll’s 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), to which Carroll replied in his post:
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.
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) — are an emergent organism rather than a zero-day fully realized creature — makes a difference. Perhaps the question will continue to move us away from arbitrary habits and ways of thinking, especially those which place us at the center of the universe.3 So, the question may be meaningful rather than “good” or meaningless. Or, as Carroll wrote, help us to be wary of ingrained “intuitive and metaphorical reasoning.” (p. 13)4
 Compare Krauss, ibid, “Science changes the meaning of questions, especially why-like questions, as it progresses.” (Preface) He talks about Kepler’s planets and First Cause as well. But Krauss also allows a language of formlessness and emergent form (and later in Chapter 10 the terms featureless-ness versus a feature-full cosmos). And I like his remark: “The fact that we need to refine what we mean by ‘common sense‘ in order to accommodate our understanding of nature is, to me, one of the most remarkable and liberating aspects of science.” And he asks, “Can one ever say anything other than the fact that the nothing that became our something was a part of ‘something’ else, in which the potential for our existence, or any existence, was always implicit?” He has a more pragmatic agenda — tackling answerable physical questions, and makes no “claims to answer any questions that science cannot answer.”
Carroll shares that pragmatic tone in his post (“as a contribution to a volume on the philosophy of physics, not the philosophy of religion”).
The right question to ask isn’t “Why did this happen?”, but “Could this have happened in accordance with the laws of physics?”
So, although in Chapter 25 of his book, Carroll refers to the maxim “ex nihilo, nihil fit,” he does not get into the theological history of ex nihilo.
[Wiki] In theology, the common phrase creatio ex nihilo (“creation out of nothing”), contrasts with creatio ex materia (creation out of some pre-existent, eternal matter) and with creatio ex deo (creation out of the being of God). Creatio continua is the ongoing divine creation.
Krauss also asks, “What is the difference between arguing in favor of an eternally existing creator versus an eternally existing universe without one?” Carroll has no “gigantic turtle” story in his paper. Krauss likewise has a brute fact conclusion: “The universe is the way it is, whether we like it or not.” And he spends some time clarifying the notion of nothing like Carroll does (especially in Chapter 9).
In the context of moving from “causes” to laws of physics, Krauss also has a useful story about dispensing with the need for angels to guide the planets. In general, his book allows time to cover more traditional theological and religious topics, such as nonbeing, Intelligent Design, and God of the Gaps, as well as introduce Occam’s razor and a limit of plausibility (cf. Carroll’s discussion of credence).
Krauss also discusses the multiverse and anthropic arguments. He concludes that “Until we open our eyes and let nature call the shots, we are bound to wallow in myopia.” (p. 178)
Carroll’s paper concludes:
… at least some properties of our particular universe are ultimately contingent. … We are always welcome to look for deeper meanings and explanations. What we can’t do is demand of the universe that there be something we humans would recognize as a satisfactory reason for its existence.
 In his preface, Krauss uses a story about gigantic turtles to illustrate an infinite regress, a contingent chain:
These arguments always remind me of the famous story of an expert giving a lecture on the origins of the universe (sometimes identified as Bertrand Russell and sometimes William James), who is challenged by a woman who believes that the world is held up by a gigantic turtle, who is then held up by another turtle, and then another . . . with further turtles “all the way down!” An infinite regress of some creative force that begets itself, even some imagined force that is greater than turtles, doesn’t get us any closer to what it is that gives rise to the universe.
 Cf. Space.com: “Our Universe Isn’t As Special As We’d Like to Believe” (February 13, 2018).
The early Greeks knew the Earth was round, but most of them could not imagine that the land they walked on was anything but the dead center of reality.
It took more than 350 years for the Catholic Church to apologize (in 1992!) for imprisoning the great heliocentrist astronomer Galileo Galilei and forcing him to recant his description of the solar system.
In the modern era, no serious thinker argues that the Earth has some special physical centrality in the universe. … All the evidence of the great telescopes has shown that Earth is just another small, rocky world orbiting a smallish sun in a far-flung region of a medium-size galaxy.
 There’s quite a spectrum of comments to Carroll’s post. I like the comment containing a reminder about the “fallacy of composition.” And the one about “a frame of reference whereby people and societies can figure out how to live” and spurious ideas versus “time-tested, complex products of evolution.”
I first explored this question in grad school. After studying theology, I started a program in philosophy and psychology. Weird (if not senseless) questions like “Why is there something rather than nothing at all?” But also the problem of universals and cognitive theory.
In everyone’s consciousness there is a sense of the “big picture,” “what it’s all about,” a world view, a cosmology (vague, yes). One of my assumptions is that how a man describes himself and his environment, world, and/or universe affects his behavior. Likewise, as a learning being, his behavior and experience affect his description.That is, percepts, concepts, and behavior are interrelated and interact with each other. [Proposed thesis paper April, 1973]
Regarding philosophy of science, I assume that we’ve moved beyond logical positivism (see Wiki’s Critics and Retrospect sections on the term). Perhaps the context of universal statements includes universal questions, eh, regarding verification, validity or truth.
So some other comments (to Carroll’s post/paper) address whether the question is meaningless. (As distinct from not meaningful?) Krauss sets the question in a class of questions which are really “how” questions. One might also just take a pragmatic position — what questions or type of questions might produce useful results (be that technological, social, etc.). Or the context of expectations for the question — that something new might be learned or observed.
Is there “something” only because there’s an observer? (If a tree falls in the forest … I think therefore I am — there is something.) Quantum physics is increasingly based on the reality of things that cannot be observed. Yet, we increasingly can observe things at the atomic level. And theory increasingly guides experimental observation and detection — confirmation of predictions.
There’s a complex historical context to the concept of nothing (other than “nothing” being a reification). And whether it’s a sensible concept. Both Carroll and Krauss spend time discussing the contemporary framework. Empty space, non-existence, quantum vacuum, energy, space and time. Krauss sees a grasp of a “deeper nothing.”
In some ways, I see the scientific method (and frameworks of credence) as ways to increasingly move away from arbitrariness in habits and ways of thinking, especially those which place us — individuals, groups, nations, planet — at the center of the universe. That is, help us get beyond tribal beliefs (while celebrating cultural diversity).
The question “Why is there something rather than nothing?” has value in addressing that context — a mashup of what people consider facts and their behaviors and beliefs, including sources of authority and tolerance of uncertainty.
Interdisciplinary insights might help, as in biology, sociology, neuroscience (cf. Brain Games) and language development; and the context of shared values and species survival.