23 February 2012
That’s the title of a glowing write-up in the New York Times Science section two days ago (Feb. 21) about the latest in a series of book trumpeting a supposed solution to the mystery of existence.
The book under review is Lawrence Krauss’s A Universe from Nothing (Free Press, 2012). It is basically a superior and accessible rehashing of the concept of the “landscape,” also known as the “multiverse”—the idea that our universe is embedded within an ensemble of other universes.
Though according to this hypothesis our universe is a “part” of the landscape in some sense, it has no spacetime connection with any of the other universes. This means that they can have no causal influence on us, or we on them.
That makes it tough to gather evidence that these other universes actually exist—but let that pass.
I won’t go into the details of the arguments for and against the landscape hypothesis here. There is no lack of popular books covering this material.(1)
In any case, the point of greatest interest is the extent to which the proposal is ad hoc speculation—as opposed to a genuine inference from hard facts—and on this point, expert opinion is divided. So, being no expert myself, I reserve comment.
In any event, it’s irrelevant to Krauss’s extravagant principal claim in the book—that the problem of the mystery of existence has been solved (more on that in a moment). With respect to this claim, it is pretty obvious that the landscape (if it exists) is no closer to being nothing than the visible universe we observe around us.
Rather the contrary, I’d have thought.
But more to the point, the landscape idea as such is not even directed at the mystery-of-existence question. Rather, it is directed at the fine-tuning problem.
This is the problem of explaining why there seems to be no good reason why a large number of physical constants take the exact values that they do. What makes this problem more interesting is the fact that if the values in question had been only slightly different, then various conditions necessary for the presence of life would not have been fulfilled.
This leads, naturally enough, to the idea that the universe is a “put-up job,” in the memorable words of the late Fred Hoyle, a distinguished astrophysicist who valued plain speaking.
The reason why the landscape idea seems to solve the fine-tuning problem is that it makes room for the thought that the values of the physical constants of all the different universes are set as they are at random.
In that case, it is hardly surprising that we find ourselves living in the universe with the values that make our existence possible. So, the theory does seem to address the fine-tuning problem—assuming, that is, the landscape exists and the random-constant concept make sense (and those are big assumptions).
But none of this has anything to do with Krauss’s principal claim about science’s now having explained the mystery of existence. So, let’s take a look at that.
If you haven’t encountered it before, the idea can be a little elusive. Indeed, it seems to have eluded Krauss.
The basic idea is traceable to Antiquity. More specifically, it is one of those respects in which Athens had to go to school to Jerusalem, for it was only in the highest reaches of the monotheistic tradition of thought—Augustine, al-Farabi (left), Ibn Sina, Anselm of Canterbury, Maimonides—that the problem of the mystery of existence finally became clearly articulated.
In a nutshell, it’s this: There is no contradiction involved in supposing that the universe never existed.
In other words, while I cannot consistently imagine a square circle, I can consistently imagine that nothing at all ever existed.
This means the universe is what philosophers call “contingent” (meaning not logically necessary).
This means that, since the universe apparently did not have to exist, we are entitled to ask why it does in fact exist.
Note that it does not help to say that the universe had to exist according to the laws of nature—by physical necessity as opposed to logical necessity—because the concept of natural law already assumes the existence of nature. Or, if one prefers to take a Platonist view of natural law, then one can simply move the question to that plane and inquire into the reason for the existence of Plato’s heaven. Therefore, invoking the laws of nature in this context is question-begging.
As an aside, one might well wonder: How is God an improvement over the laws of nature, in this respect? That’s a good question.
Theologians speak of God’s mode of being as “necessary,” unlike the world’s, which is contingent, as we have seen. So, it is a crude mistake simply to ask, as atheists are wont to do: “Who made God?”
However, it is not clear (to me, at any rate) that the concept of necessary being is fully intelligible. The question is: What sort of necessity are we really talking about? It certainly seems like we can imagine that God doesn’t exist without contradicting ourselves. But if that is so, then all really existing things—not just the universe, but God as well—turn out to be contingent.
There are several ways to go here, for the theist. One is to distinguish a third type of necessity, stronger than physical necessity, but weaker than logical necessity. Another is to distinguish among different modes of being. For instance, one might argue that God—as the source of Being (upper case) itself—must be distinguished from all individual beings (lower case), including the universe as a whole. And if that is right, then it is easier to see how the former can be necessary, whereas the latter are contingent.
This is a vast subject. Luckily, though, it need not detain us further here. For, I am not defending the claim that God is a sufficient solution to the mystery of existence.
What I am doing is attacking Krauss’s claim that science provides such a solution.
To return, then, to the main thread of my argument: It seems a perfectly coherent question to ask why the universe exists, and if that is so, then we evidently have every right to seek an answer to the question.
The late-antique and medieval Christian and Islamic thinkers who first clearly saw all this liked to express the point slightly differently: Creator and creation are two radically distinct things.
As Robert Sokolowski, a distinguished philosopher at the Catholic University of America, has put it:
[T]he Christian understanding introduces a new horizon or context for the modes of possibility, actuality, and necessity . . . [it] distinguishes the divine and the world in such a way that God could be, in undiminished goodness and greatness, even if everything were not.(2)
The idea received its classical modern statement in a little essay by Leibniz (right) called “On the Radical Origination of Things” (1697). Here is how he put the problem:
For a sufficient reason for existence cannot be found merely in any one individual thing or even in the whole aggregate and series of things. Let us imagine the book on the Elements of Geometry to have been eternal, one copy always being made from another; then it is clear that though we can give a reason for the present book based on the preceding book from which it was copied, we can never arrive at a complete reason, no matter how many books we may assume in the past, for one can always wonder why such books should have existed at all times; why there should be books at all, and why they should be written in this way. What is true of books is true also of the different states of the world; every subsequent state is somehow cpied from the preceding one (although according to certain laws of change). No matter how far we may have gone back to earlier states, therefore, we will never discover in them a full reason why there should be a world at all, and why it should be such as it is.(3)
In modern parlance—following Leibniz’s lead—the problem of the mystery of existence is most often expressed by means of the formula: “Why is there something rather than nothing?” This phrase also forms the subtitle to Krauss’s book.
Put like that, the idea does not seem so difficult to grasp. In fact, it can be reduced to three little words:
Why not nothing?
Nevertheless, Krauss doesn’t get it. He titles one of his chapters “Nothing is something.” What does he mean by this?
Just the familiar idea that according to quantum field theory, the vacuum state has complex properties such that matter can be created through quantum fluctuation events. As Krauss puts it in the title of another chapter: “Nothing is unstable.”
But the properties of the quantum vacuum are simply irrelevant to the question under discussion—the reason for the existence of anything at all—which Krauss has brazenly claimed to have solved in the title of his book. For, in spite of his protestations to the contrary, the quantum field is obviously not nothing in the relevant sense.
What, then, is the final verdict on Dr. Krauss’s latest book?
Yet another example of a perfectly good scientist out of his philosophical depth.(4)
(1) Stephen Hawking and Leonard Mlodinow, The Grand Design (Bantam, 2010); Lee Smolin, The Life of the Cosmos (Oxford UP, 1997); Leonard Susskind, The Cosmic Landscape (Little, Brown, 2005); Alex Vilenkin, Many Worlds in One (Hill and Wang, 2006).
(2) Robert Sokolowski, The God of Faith and Reason (University of Notre Dame Press, 1982); p. 41. See, also, Lloyd P. Gerson, God and Greek Philosophy (Routledge, 1990).
(3) Gottfried Wilhelm Leibniz, Philosophical Papers and Letters, ed. by Leroy E. Loemker (Kluwer Academic, 1989); p. 486.
(4) For further discussion, see John Leslie, Universes (Routledge, 1990); Milton K. Munitz, The Mystery of Existence (Appleton-Century-Crofts, 1965); and Robert Nozick, Philosophical Explanations (Harvard UP, 1981).