by Jim Holt
But then there was a noisy burst of activity. A woman of a certain age, evidently an old friend of Jimmy’s, breezed through the front door, accompanied by a pair of what appeared to be Cuban gigolos dressed in shell suits. Giggling and grinding their teeth, this trio sat down with us and began to jabber away. The woman’s face was a sallow mask of leathery jollity, and she talked in a low croak that put me in mind of Jeanne Moreau. I listened with a kind of ironic inattention, but my spirits began to flag.
It seemed a good time to leave.
The late-night air was chill and damp. As I started to walk back to my hotel, I glanced across the deserted square at the Église de Saint-Germain-des-Prés, built a thousand years ago. There, in one of the side chapels, reposed the body of Descartes. (Well, most of it, anyway—the whereabouts of his skull and right forefinger is a mystery.)
I wondered if Sartre, scribbling inside the Café de Flore, used to feel the Cartesian presence from across the square. And Descartes wasn’t the only philosophical specter lurking about. Directly across the Boulevard Saint-Germain from the café is the rue Gozlin, which runs for a single block. It is the last vestige of the rue Sainte-Marguérite, a medieval street that was absorbed into the boulevard during Baron Haussmann’s modernization of Paris in the mid-nineteenth century. There, some centuries ago, stood the Hôtel des Romains, where Leibniz lived for two of the very happy four years of his life he spent in Paris.
What was Leibniz doing in Paris? As usual with him, intrigue lay behind his visit. He had come to the French capital in 1672 on a secret diplomatic mission to persuade Louis XIV to invade infidel Egypt rather than Christian Germany. The mission was not a success. “As to the project of Holy War,” the Sun King was said to have politely responded to Leibniz, “you know that since the days of Louis the Pious such expeditions have gone out of fashion.” (In the event, France invaded Holland.)
But Leibniz’s time in Paris was hardly wasted. It was while staying in the Hôtel des Romains, in his thirtieth year—something of an annus mirabilis for him—that he invented the calculus (including the dx notation and the elongated “S” symbol for the integral that are in universal use today). And it was at that hotel, in his room overlooking the present site of the Café de Flore, that Leibniz began to lay the foundations for his later metaphysical philosophy, which would culminate with the posing of the deepest of all questions: Why is there something rather than nothing?
Both Leibniz and Descartes, in their rationalist way, confronted the mystery of existence. Both decided that the one sure ontological foundation for a contingent world like ours was an entity that carried within itself the logical guarantee of its own existence. Such an entity, they held, could only be God.
Like his philosophical forebears, Sartre too was a rationalist. Unlike them, he thought that the very idea of God was shot through with contradictions. Either a being has consciousness or it does not. If it does, it is pour soi (“for itself”), an activity rather than a thing, a “wind blowing from nowhere toward the world.” If it does not have consciousness, it is en soi (“in itself”), an object fixed and complete. God, were such a being to exist, would have to be both pour soi and en soi: both conscious and complete in himself. And that, submitted Sartre, is an impossibility. Still, this God-like combination of fluidity and fixity is one we humans cannot help aspiring to. Our desire to be radically free and yet absolutely secure in our identities is, for Sartre, nothing less than a desire to be God. It is mauvaise foi (“bad faith”), a sort of original sin. It was what, according to Sartre, my waiter at the Café de Flore was displaying. “His movement is quick and forward, a little too precise, a little too rapid. . . . He bends forward a little too eagerly; his voice, his eyes express an interest a little too solicitious for the order of the customer. . . . He is playing, he is amusing himself. But what is he playing? We need not watch long before we can explain it: he is playing at being a waiter in a café.” But a consciousness can never have an essence, like waiterhood or divinity. Thus God is a conceptual absurdity. And man is “a useless passion.”
Such Sartrean reflections engrossed me as I set out on my nocturnal walk home—past the elegantly illumined Théâtre de l’Odéon, around the edge of the Jardin du Luxembourg, and then toward my hotel in Montparnasse—which was not far, as it happened, from the cemetery where Sartre and Simone de Beauvoir are buried (Susan Sontag too). The quiet that comes over Paris in the small hours—on some streets you can even hear the echo of your footfall, which is unthinkable in New York—made my thoughts seem clear and compelling and true.
The next morning, however, a metaphysical fog had descended on me again. I wondered whether there wasn’t something unwholesome about the Café de Flore. Sartre’s paradoxes seemed too easy to me, his ontological despair slightly off key. After all, Leibniz and Descartes were far greater philosophers than he ever was. And both of them were convinced that the world of contingent being—the one Sartre found so gooey and absurd, so permeated with nothingness—must rest on a secure and necessary ontological foundation.
There must be serious thinkers who still believed this. But I wasn’t going to find them easily on the Left Bank, not, at least, in this century. Better to look for enlightenment in a more cloistral, medieval setting. So, after grabbing a tartine et café crème at the bar of Le Select, I hauled my bags onto the Métro and headed to the Gare du Nord, there to catch the Eurostar train to London. Arriving at Waterloo Station a few hours later, I caught the tube to Paddington, where I hopped on a local train to Oxford, debouching from the station into that city of dreaming spires well in advance of cocktail hour.
“I HAVE BEEN here before,” I thought to myself (rather derivatively) as I made my way down Oxford’s High Street. And I had—for the wedding of a friend just a few months earlier. Now it was midwinter, Hilary Term, and the clear light of the late afternoon leant an apricot glow to the Cotswold sandstone of Oxford’s colleges. Bells rang out over the gables, cupolas, and finials. Students hurried to and fro through the Gothic labyrinth of passageways, cloisters, alleys, and quadrangles. All around me I felt the soft breath of a thousand years of learning.
So much for the bogus poetry. Where was the next clue to the mystery of the world’s existence?
I had a pretty good idea. Years ago, in a stack of galleys I had been sent to review, one slim volume stood out. Its title, Is There a God?, was not in itself remarkable. Books with titles like that are a dime a dozen. What struck me were the credentials of the author, whose name was Richard Swinburne. He was a philosopher of religion, a practitioner of what is called “natural theology.” But he was also a philosopher of science, the author of rigorous treatises on space, time, and causality. And he was clearly a thinker alert to the mystery of existence. “It is extraordinary that there should exist anything at all,” I read on the back cover of the volume. “Surely the most natural state of affairs is simply nothing: no universe, no God, nothing. But there is something. And so many things. Maybe chance could have thrown up the odd electron. But so many particles!” What could account for the existence of such a rich and plenitudinous universe? And what could account for its many surprising features—notably its spatial and temporal order, its fine-tuned fostering of life and consciousness, its suitability as a theater for human action? “There is a complexity, particularity, and finitude about the universe that cries out for explanation,” he wrote.
The simplest hypothesis that explains the existence of such a world is the hypothesis that God is behind it—that was Swinburne’s conclusion. Admittedly, it was not a very original one. What was original was Swinburne’s methodology. He did not pretend to prove God’s existence by means of an abstract logical deduction, in the manner of Anselm, Aquinas, or Descartes. Instead, he used modern scientific reasoning. He endeavored to show that the God hypothesis was at least probable, more probable than its negation, and hence that belief in God was rational. “The very same criteria which scientists use to reach their own theories lead us to move beyond those theori
es to a creator God who sustains everything in existence,” Swinburne wrote. Each step in his case was painstakingly justified by appeal to the canons of inductive logic. He was especially expert in the use of “Bayes’s theorem,” a mathematical formula that describes how new evidence raises or lowers the probability of a hypothesis. Using Bayesian confirmation theory, Swinburne sought to show that on the total evidence—which includes not just the existence of the universe, but also its lawfulness, the patterns of its history, and even the presence of evil within it—it was more likely than not that there is a God. Intellectually, this struck me as a bravura performance. Yet I knew that it did not strike everyone that way. Swinburne’s fellow philosopher of science, Adolf Grünbaum, had been withering in his scorn for Swinburne’s pro-theist case, calling it “a very poor job.” Swinburne’s reasoning in behalf of theism was “unsound” and “defective,” Grünbaum had told me, full of “red herrings” and “strawmen.” Over the years, Swinburne and Grünbaum have tussled repeatedly in forums like the British Journal for the Philosophy of Science. When I went back and read their exchanges, it was like witnessing a fiendishly intricate metaphysical Ping-Pong match. “Why, oh why,” Grünbaum irritably asked at one point, “does Swinburne reason with Leibniz that even the bare of existence of the universe imperatively calls for a ‘cause acting from outside’?”
Richard Dawkins was also skeptical, to say the least. In The God Delusion, Dawkins mocked Swinburne’s claim that the God hypothesis possesses the scientific virtue of simplicity, calling his reasoning “a breathtaking piece of intellectual chutzpah.” How, Dawkins asked, could a being who created and sustained a complex universe like our own, a being supposedly capable of monitoring the thoughts of all his creatures and answering their prayers (“Such bandwidth!”), be simple? As for Swinburne’s argument that the existence of an omnipotent and infinitely loving God could be squared with a world containing evil and suffering, Dawkins deemed it “beyond satire.” He recalled a televised discussion in which Swinburne (in Dawkins’s words) “attempted to justify the Holocaust on the grounds that it gave the Jews a wonderful opportunity to be courageous and noble”—at which point a fellow panelist, the Cambridge chemist and arch anti-theist Peter Atkins, growled at Swinburne, “May you rot in hell.”
A man capable of producing such bold reasoning about the cosmos, and of evoking such acidulated reactions among his foes, was clearly a man worth talking to. Swinburne had recently retired from Oxford, where he had been the Nolloth Professor of the Philosophy of the Christian Religion and a fellow of Oriel College. When I managed to get in touch with him, he was the soul of kindness, inviting me to come over to his residence in North Oxford for tea and a chat.
So the next afternoon I left my hotel on the High Street, made my way down Queens Lane, passed under the Bridge of Sighs and by the Bodleian Library and Ashmolean Museum, and emerged finally onto the broad Woodstock Road, which I followed for a mile or two to North Oxford. I chanced to notice an Eastern Orthodox Church as I turned off the main road to seek the address Swinburne had given me, which proved to be that of a 1950s modernist apartment block bordered by a row of handsome Edwardian brick houses. The still winter air of the neighborhood was improbably rich with birdsong. It seemed a good portent.
6
THE INDUCTIVE THEIST OF NORTH OXFORD
“You’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 evoluti
on 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?