In a previous post, I have suggested that that might well be the best response to this question, because the existence of the universe is a brute fact that cannot and need not be explained, and the idea of absolute "nothing" that comes from the Christian theological idea of creation ex nihilo is not rationally comprehensible since it is beyond our natural experience of the world.
But some people insist that the existence of the universe needs to be explained, and particularly if the universe had a beginning in the Big Bang, then there must be a transcendent cause for the universe coming into being. And that transcendent cause must be a powerful disembodied mind--God. In this way, the modern cosmologists who believe that the universe began in the Big Bang might seem to be supporting a crucial premise for the cosmological argument for the existence of God.
Moreover, many modern cosmologists accept the anthropic principle--that the universe has been fine-tuned to provide the conditions for the emergence of human life--and thus they seem to be endorsing a premise for the teleological argument for the existence of God, as the intelligent designer of a universe that is purposefully designed to be habitable for human beings.
That's the claim of William Lane Craig and other Christian apologists who think modern science does indeed support some of the premises for some of the classic arguments for the existence of God. As I have indicated in some previous posts (here, here, and here), some modern scientists--Owen Gingerich, for example--agree with Craig about this. But most do not. Sean Carroll and Lawrence Krauss are two cosmologists who have debated Craig and argued that modern science supports naturalism rather than theism. Here are two videos of these debates:
Here is Craig's syllogism for the Cosmological Argument:
1. If the universe began to exist, then there is a transcendent cause which brought the universe into existence.
2. The universe began to exist.
3. Therefore, there is a transcendent cause which brought the universe into existence.
Craig claims that (1) is "obviously true," because no one believes that things just "pop into existence" without a cause, and if the whole universe came into existence at some point in time, the cause must have been transcendent--namely, a divine First Cause.
The controversial premise, he says, is (2). Previously, traditional proponents of the Cosmological Argument have made logical arguments for why the universe could not be eternal and so must have an absolute beginning in time. But now, beginning in the 20th century, we have scientific empirical evidence from astrophysical cosmology supporting the theory of the Big Bang--most importantly, evidence for the expansion of the universe and evidence from the second law of thermodynamics that the universe has moved from an original state of low entropy to high entropy.
Craig says that the scientific support for premise (2) coming from Big Bang cosmology is "religiously neutral," but when the empirical truth of premise (2) is combined with the metaphysical truth of premise (1), the logical conclusion supports the existence of a transcendent cause of the universe that must be God.
There are, however, good reasons to doubt those two premises as scientific statements rather than affirmations of religious faith.
Premise (1) is not "obviously true," because while we all have experience of how natural causes work within the universe to bring things into existence, we do not have experience with how transcendent causes work outside the universe to bring the universe itself into existence.
Carroll makes this argument, and Craig refuses to answer it. Craig just repeats how silly it sounds to say that things "just pop into existence" without a cause. But as Carroll observes, the language of "popping" implies a context within which cause and effect relationships make sense. So we can sensibly ask why the chicken crossed the road, because we have a contextual understanding of what roads are, what might be on the other side of a road, what might motivate chickens to cross a road, etc. We have a context here of things interacting within a universe governed by natural laws.
But if we try to ask why the universe exists, we have no context outside the universe that would make it possible for us to seek a causal explanation. Indeed, to even talk about transcendent causes implies that our natural experience of causality inside the universe has no application here. Thus, Craig is employing the sophistical technique of equivocation: if it's silly within our natural experience of the universe to say that things can just "pop into existence," then it is also silly standing outside our natural universe to say that our universe could have come into existence without a cause. This is a fallacious inference, because our ordinary experience of causality within the context of the universe does not necessarily apply outside that context.
As Carroll says, our natural experience of causality is in the context of time, so that things happen now because of things that happened in the past. But if the beginning of the universe in the Big Bang was the beginning of time, then there is no context of time for that beginning--there is no "before" the beginning. So while "popping into existence" sounds silly, "there was a first moment of time" does not sound so silly.
Consequently, while the "principle of sufficient reason"--that for everything there must be a causal explanation--might hold true for our ordinary experience of how things work within the universe, this principle does not necessarily apply to what things are like outside the universe, because none of us has ever stood "outside the universe" to see if the principle of sufficient reason holds true there. Standing "outside the universe"--experiencing the transcendent--is a matter of religious imagination that is beyond our empirical experience of the world and thus beyond empirical science.
Therefore, premise (1) of Craig's syllogism might be a statement of religious faith, but it is not a statement of scientific truth.
The same can be said about premise (2). As with Craig's premise (1), there is an implied equivocation in his premise (2). "The universe began to exist." What exactly is being stated here? There are two possibilities. The universe began to exist out of nothing. Or the universe began to exist out of something.
Craig's argument requires that he equivocate between these two different statements. The universe began to exist out of nothing is the Christian theological doctrine of creation ex nihilo. But, then, this would deny Craig's claim that this premise is "religiously neutral." In fact, that the universe began to exist out of nothing is not a scientific statement at all, because there is no human observational experience of absolute "nothing" that would make the study of "nothing" part of empirical science.
By contrast, the claim that the universe began to exist out of something can be a scientific statement, because there is human observational experience of how things can originate out of something.
Both Christian apologists like Craig and atheistic cosmologists like Krauss fail to acknowledge this point. Both sides refuse to admit that origin from something and creation from nothing are utterly different.
The title for Krauss's book A Universe From Nothing is wrong. The proper title would be A Universe From Something. Krauss proposes a model of how the universe could have evolved from a multiverse by the laws of relativistic quantum theories out of the empty space of quantum vacuum states into the universe as we observe it today. Aha, there you are, he proclaims, a universe from nothing without any need to posit a divine creator! But notice that there is no absolute "nothing" here. He assumes at the origin of the universe the reality of the laws of quantum mechanics and of quantum vacuum states. That's not nothing! That's something!
In a way, he even admits this when he writes: "to be fair, to make any scientific progress in calculating possibilities, we generally assume that certain properties, like quantum mechanics, permeate all possibilities. I have no idea if this notion can be usefully dispensed with, or at least I don't know of any productive work in this regard" (176-77).
So where are the laws of quantum mechanics supposed to have come from? He has no idea. And if our universe came out of the multiverse, where did the multiverse and the laws governing it come from? He has no idea. He can explain how the universe might have come from something, but not how it might have come from nothing.
In his lectures, Krauss likes to tell the story of how the first cosmologist to propose a Big Bang theory of the universe was a Jesuit priest--Georges Lemaitre--and how, when Pope Pius XIII in 1951 pointed to Lemaitre's Big Bang theory as scientific evidence for divine creation of the universe from nothing, Lemaitre criticized the Pope for failing to see how this scientific theory had nothing to do with the Christian doctrine of creation.
But what Krauss doesn't say is that Lemaitre explained that the theory of the Big Bang is not a theory of how the universe could arise "out of nothing," but rather it is a theory of how the universe could arise from what Lemaitre called a "primeval atom," or from a hyper-dense sphere of cold matter, disintegrating through radioactivity into an expanding universe, or from what some people called "the cosmic egg." Lemaitre thus separated the scientific theory of the universe's origin from something and the religious doctrine of the universe's creation from nothing. Here Lemaitre was in agreement with St. Thomas Aquinas, who declared that "It is by faith alone do we hold and not by any demonstration that can be proved, that the world did not always exist. . . . that the world began to exist is an object of faith, but not of demonstration or science" (Summa Theologica, I, q. 46, a. 2).
Krauss says nothing about this, because he wants to claim that his scientific theory of origin is actually an explanation of "a universe from nothing," which Lemaitre denied as a scientific claim. (My understanding of Lemaitre's position depends greatly on John Farrell's book The Day Without Yesterday: Lemaitre, Einstein, and the Birth of Modern Cosmology . Farrell has kindly confirmed in an email message that my interpretation is correct.)
Oddly, Craig makes exactly the same mistake as Krauss, because Craig repeats the Pope's claim that Big Bang theory confirms the scientific truth of creation from nothing, without answering Lemaitre's objections.
But, then, what about Craig's Teleological Argument? Here is how he frames it:
1. The fine-tuning of the universe is due to either physical necessity, chance, or design.
2. It is not due to physical necessity or chance.
3. Therefore, it is due to design.
By "fine-tuning of the universe," Craig is referring to certain fundamental constants and quantities, such as the gravitational constant and the amount of entropy in the early universe, that apparently must be exactly as they are for a universe hospitable to life to emerge.
In his response to Craig, Carroll admits that this teleological argument from fine-tuning is "the best argument that theists have when it comes to cosmology" (47). Nevertheless, he offers five reasons why theism is not a solution to the purported fine-tuning problem:
1. Fine-tuning for life is dubious at best.
2. God doesn't need to fine-tune anything. He's God.
3. Fine-tunings may be only apparent.
4. The multiverse is an obvious naturalistic explanation for fine-tuning.
5. Theism fails as an explanation for purported cosmological fine-tuning, because theism is so badly defined that it does not make precise falsifiable predictions about how God has fine-tuned the universe.
As I indicated in my post on Owen Gingerich (here), the evidence of cosmological fine-tuning does not clearly show a fine-tuning for human life. If we look at the entire history of the cosmos, we see that during the first 10 billion years, there was no life, during the first 13 billion years, there was no human-like intelligent life, and in the remote future, as the Sun and the other stars burn out, the universe will become dark, cold, and dead. So we could conclude that the universe has been fine-tuned for an eternity of mindless death, and so from the point of view of the universe, we are utterly insignificant.
It does not follow from this, however, that if the universe does not care about or for us, our lives have no meaning. As Carroll argues, and I agree, even if our lives have no cosmic meaning, they still have human meaning for us. The universe doesn't care. But we care about ourselves and others. Showing how this supports a naturalistic account of human morality and politics will be the subject of my next post.