Why Does the World Exist?: An Existential Detective Story (13 page)

6

THE INDUCTIVE THEIST OF NORTH OXFORD

“
Y
ou’ve come a long way,” said Richard Swinburne as he welcomed me at his doorstep. Yes, I thought to myself, I have—all the way from the Café de Flore of post-Sartrean Paris to a philosopher-monk’s cell in medieval Oxford.

Swinburne, born in 1934, was lithe and youthful-looking for a man in his mid-seventies. He had pleasant, rather clerical features, and a serene manner. His forehead was high and narrow, topped by a full head of gray hair. He spoke in a quiet voice, with a slightly nasal timbre, precise vowels, and an infinity of subtle modulations. He was wearing a nicely tailored dark suit and a sweater, which was tucked into his pants.

Swinburne, I discovered, lived alone in his cozily austere duplex apartment. We walked up a narrow flight of stairs to his study, where a crucifix hung on the wall. He absented himself for a moment and returned with a pot of tea and a plate of sugar biscuits.

I mentioned the interesting day I had spent with his great cosmological adversary, Adolf Grünbaum, and how dismissive Grünbaum had been of Swinburne’s beliefs—in particular, his conviction that the sheer existence of the world cried out for some kind of explanation.

“Grünbaum misunderstands me,” he responded mildly, in the manner of a curate discussing a difficult rector. “He represents me as saying that reality ought to be geared to throw up Nothing, and that it is unusual and surprising that it has thrown up Something. But that’s not my position. My position is based on an epistemological principle: that the simplest explanation is most likely to be
true
.”

And why, I asked, is simplicity such an epistemic virtue?

“There are innumerable examples to illustrate this,” he said, “and not just from science. A crime has been committed. A bank has been robbed. There are three clues. A chap called Jones was reported to be near the scene of the crime at the time of the robbery. Jones’s fingerprints were found on the safe. Money from a bank robbery was found in Jones’s garret. Plausible explanation: Jones did the crime. Why do we think that? Well, if the hypothesis that Jones did the crime was true, you would probably find such clues; and if it wasn’t, you probably wouldn’t. But there are an infinite number of other hypotheses that meet this dual condition—for example, the hypothesis that somebody dressed up like Jones as a joke and happened to walk near the bank; and another person, not in collusion with the first, had a grudge against Jones and put Jones’s fingerprints on the safe; and a third person, having no connection to the previous two, put the proceeds from a quite different robbery in Jones’s garret. That hypothesis also meets the dual condition for being true. But we wouldn’t think much of any lawyer who put it forward. Why? Because the first hypothesis is
simpler
. Science always reaches for the simplest hypothesis. If it didn’t, one could never move beyond the data. To abandon the principle of simplicity would be to abandon all reasoning about the external world.”

He looked at me gravely for a moment and then said, “Would you like some more tea?”

I nodded. He refilled my cup.

“Descriptions of reality can be arranged in order of their simplicity,” Swinburne continued. “On
a priori
grounds, a simple universe is more likely than a complicated one. And the simplest universe of all is the one that contains
nothing
—no objects, no properties, no relations. So, prior to the evidence, that is the hypothesis with the greatest probability: the hypothesis that says there is Nothing rather than Something.”

But simplicity, I said, did not force this hypothesis to be true. I refuted it by holding up a sugar biscuit.

“Right,” said Swinburne, “so the question is, what is the simplest universe that contains the sugar biscuit and the teapot and us and everything else we observe? And my claim is that the simplest hypothesis explaining it all is the one that posits God.”

The notion that there’s anything simple about the God hypothesis is one that drives a lot of atheist thinkers—Richard Dawkins, for example—up a wall. So I had to challenge Swinburne on that. First, though, a slightly less fraught subject: did it matter to his case for God whether the universe had a finite or an infinite past?

“I know that a lot of thinkers look at the Big Bang through metaphysical spectacles,” he said. “But I don’t think the issue of a cosmic beginning is deeply relevant. Nor did Aquinas. Aquinas thought that, as far as philosophy was concerned, the universe might well have been infinitely old. It was a matter of Christian revelation that it came into existence at a particular moment in time. That’s one way of reading Genesis. But suppose the universe has been going on forever, and that it’s always been governed by the same laws. It remains true that there
is
a universe, and there might
not
have been. Whether the laws that govern its evolution have been in operation for a finite or an infinite time, they’re still the same datum. And, for those laws to give rise to humans, they have to be of a very special sort. You might think that, given an infinite amount of time, matter will rearrange itself sufficiently to produce conscious beings. But that’s not so! Think of the balls careening around on a billiard table. Even in an infinite time, they will not assume all possible configurations. A cosmos must meet some very precise conditions in order for humans to appear.”

But what if our world is just one among a vast multitude of universes, each with different laws? Wouldn’t some of them be bound to produce beings like us?

“Yes, I know that the multiple-universe idea has captured a lot of headlines,” he said. “But that’s not relevant to my case either. Suppose each universe throws off daughter universes that differ from the mother universe in various ways. How can we know such daughter universes exist? Only by studying our own universe and extrapolating backwards and finding that, at some point, another universe must have split off from it. Our sole source of knowledge about
other
universes is a detailed study of
this
universe and its laws. How then can we suppose that those other universes are governed by totally
different
laws?”

Perhaps, I said, the laws governing the other universes were the same, but the “constants” that occurred in those laws—the list of twenty or so numbers that determine the relative strength of the physical forces, the relative masses of elementary particles, and so forth—differed from one universe to the next. If our universe is but one among a vast ensemble of universes in which such constants varied at random, then isn’t it to be expected that some of these universes should have the right mix of constants for life to occur? And, as humans, wouldn’t we be bound to observe ourselves living in one of the universes whose features happened to be congenial to our existence? Doesn’t this “anthropic principle” make the apparent fine-tuning of our universe wholly unremarkable? And, in that case, wouldn’t the God hypothesis be unnecessary as an explanation of why we are here?

“Right,” he said, with a faintly audible chuckle, as though he had heard this very point innumerable times before. “But then we would need to find a
law
of how these constants varied from universe to universe. If the simplest theory is one where the constants of nature undergo some change when a mother universe gives birth to a daughter universe, then that raises the question of why the multiverse is like that, as opposed to all the infinite
other
ways a multiverse might be. Those other multiverses would
not
give rise to universes with life. In any case, to posit a trillion trillion other universes to explain the life-fostering features of our universe seems slightly mad when the much simpler hypothesis of God is available.”

But is the God hypothesis really all that simple? There is, I was willing to concede, a sense in which God might be the simplest thing imaginable. The God of the theologians is defined as the entity—or “substance,” to use the technical term—that possesses every positive attribute to an
infinite
degree. He is infinitely powerful, infinitely knowledgeable, infinitely good, infinitely free, eternally existing, and so forth. Setting all the parameters equal to infinity makes a thing easy to define. In the case of a finite being, by contrast, you have to say it’s of such-and-such size and has such-and-such degree of power, that it knows this much and no more, that it began to exist at such-and-such time in the past, and so on. In other words, there is a long and messy set of finite numbers to specify.

Now, in science, infinity is a very nice number, along with its opposite, zero. Neither infinity nor zero needs an explanation. Finite numbers do need explanations, however. If the number 2.7 occurs in your equation, someone will always ask, “Why 2.7? Why not 2.8?” The simplicity of zero and infinity precludes such awkward inquiries. The same logic might be said to apply to God. If the cosmic creator could make a universe only of such-and-such mass, but no heavier, then the question would arise of why there was such a constraint on its power. With an infinite God, there are no such limits to be explained.

So the God hypothesis does possess a certain sort of simplicity. But Swinburne’s God is not mere infinite substance. He also intervenes in human history. He answers prayers, reveals truths, causes miracles to occur. He even incarnated himself in human form. This is a God that acts with complex purposes. Doesn’t the ability to act according to complex purposes imply a corresponding complexity within the agent? Swinburne himself, I had noticed, seemed to assume as much in some of his writings. For instance,
in a 1989 essay
he observed that we humans could have complex beliefs and purposes only because we had complex brains. Wouldn’t God, in order to accomplish what he does, have to be internally complex on a much vaster scale—infinitely complex, in fact?

Swinburne knit his tall brow a bit when I asked the question. But in an instant, it was unknit again.

“Humans need bodies if they are to interact with the world and benefit one another,” he said. “And that necessitates having a complicated brain. But God doesn’t need a body or a brain. He acts on the world directly.”

But, I objected, if God created the world for a purpose, if he has complicated designs for his creatures, then his mind must contain complicated thoughts. So the divine “brain,” even if it is wholly immaterial, must still be a complex medium of representation, mustn’t it?

“It isn’t logically necessary to have a brain of any kind to have beliefs and purposes,” Swinburne replied. “God can see all of creation without a brain.”

Wouldn’t the ability to see all of creation, brainlessly or not, imply something other than simplicity? If God possessed within himself all knowledge of the world, wouldn’t his internal complexity have to be at least equal to that of the world?

“Hmmmm,” Swinburne said, stroking his chin. “I see what you’re getting at. But look, there are all sorts of things I can do—tie my shoelaces, for example—without thinking about how I do them.”

Yes, I said, but you can tie your shoelaces only because you have complicated neural circuits in your brain.

“That is, of course, true. But it’s one truth that I can tie my shoelaces without thinking. It’s another truth that there are certain things going on in my brain. These are two truths about the world, and they are not necessarily connected with one another.”

I wanted to protest this weird mind-body parallelism he seemed to be buying into, this idea that mental processes and brain processes somehow stream along independently of each other. But I was afraid I was beginning to bore him.

“Let me put the point slightly differently,” Swinburne said, “by way of an analogy. Someone like Dawkins might claim that science never posits the kind of ‘omni’ properties—omni-knowledge, omni-power—that we ascribe to God. But let’s look at Newton’s theory of gravitation. This theory postulates that every particle in the universe has one power and one liability. The power is to exert gravitational force, and the liability is to be subject to it. And the power is an
infinite
one: each particle influences every other particle in the universe, no matter how far away. So serious physicists have attributed an infinite power to very tiny particles. It’s considered quite proper in science to attribute omni-properties to very simple kinds of objects.”

We had apparently reached an impasse on the issue of simplicity. So I tried to find another weak point in Swinburne’s case.

“It seems to me that your God is closer to an abstract ontological principle than to the heavenly father-figure that religious believers pray to,” I said. “There may be, as you say, a supremely simple entity that explains the existence and nature of the universe. And it may even have some personal characteristics. But to equate this entity to the one that is worshipped in churches seems a bit far-fetched. It’s easy to see how today’s religions grew out of animistic cults and then got more sophisticated, as magical notions of the world gave way to scientific understanding. But those primitive cults weren’t hooking on to anything transcendental.”

“I think that’s wrong,” Swinburne said, quite abruptly and with some severity. “I think it’s
always
been a matter of the transcendental. The God written about in the New Testament and some of the Old Testament is an omnipotent, omniscient, and all-good creator. And going right back to Jeremiah, you have the idea that the visible world holds evidence of the transcendental. Jeremiah talked of the ‘covenant of night and day’ that God has made. What this means is that the regular alternation of night and day shows the
reliability
of the creator. And this is, in essence, what philosophers call the argument from design—one of the central arguments for the existence of God. The early Christian, Jewish, and Islamic traditions all have this kind of transcendental thinking in their background. They just don’t talk about it a lot, because the issue back then was not whether there is a God, but what he was like and what he had done.”