Why Does the World Exist?: An Existential Detective Story (27 page)

12

THE LAST WORD FROM
ALL SOULS

No question is more sublime than why there is a Universe: why there is anything rather than nothing.

—DEREK PARFIT

I
always knew that my quest for a resolution to the mystery of Being would bring me back to Oxford. And here I was, standing on the threshold of its most ethereal redoubt, the College of All Souls. I felt a little like Dorothy at the doors to the Emerald City. Inside was a wizard who might well have the final word on the question
Why is there something rather than nothing?
I hoped he would vouchsafe that word to me. And so he did, after a fashion. What I hadn’t counted on was that I would get a free lunch in the bargain.

ON MY WAY
from Paris back to Oxford, I had stopped for a couple of days in London—not for diversion, but to do some serious swotting up. I had made arrangements to stay at the Athenaeum Club, on Pall Mall. I arrived on a Saturday. The club was closed for the weekend. But when I rang the bell, a porter appeared at the door and let me in. He took me through the crepuscular entrance hall and past the grand staircase, above which hung a large clock. When I looked up to see the time, I noticed that the clock had two numerals for seven, but none for eight. Why, I wondered aloud, was that?

“No one really knows, sir,” the porter said, possibly with a wink.

Mystère
.

At the rear of the entrance hall was an old and tiny elevator. We took it all the way up to the club’s attic floor. I was then conducted through a maze of narrow hallways to what would be my bedroom. It was on the small side, with a couple of little windows that looked out over the statue of Pallas Athene above the portico of the club onto Waterloo Place. Adjoined to the bedroom, happily, was a capacious bath, with a large old-fashioned tub in the middle.

The Athenaeum Club has an impressive library, but I had brought my own reading material to London. It consisted of a Trollope novel—several scenes of which, as it happens, took place on the Doric-columned portico of this very club—and an essay, clipped from an old issue of the
London Review of Books
, by an English philosopher named Derek Parfit. The essay’s title was “
Why Anything? Why This?
”

My familiarity with Parfit as a thinker of rare originality stretched back to my undergraduate days. One summer vacation, while backpacking across Europe, I happened to be carrying around with me a little paperback anthology on the philosophy of mind. The last paper in that anthology, titled “Personal Identity,” was by Parfit, and I’ll never forget how, when I finally got around to reading it on a long train ride from Salzburg to Venice, it shook up my own sense of self. (Nor will I ever forgot how the prodigious quantity of bread, cheese, and dried sausage I devoured over the course of that train ride fortified my sense of corporeality.) Through a brisk and brilliant series of thought experiments, involving the successive fissioning and fusing of different selves, Parfit arrived at a conclusion that would have astonished even Proust:
personal identity is not what matters
. The permanent, identical “I” is a fiction, not a fact. There may be no determinate answer to whether, say, the callow JH who read Parfit’s essay as a student is the same self as the autumnal JH who is typing these words now.

That was how Parfit first came to my awareness. Some years later, in 1984 (by which time I was a philosophy grad student at Columbia University), he published a big book called
Reasons and Persons
. Here he meticulously drew out the implications of his theory of personal identity for morality and rationality, for our obligations to future generations and our attitude toward death. Many of Parfit’s conclusions—that we are not what we believe ourselves to be; that it is often rational to act against our self-interest; that our standard morality is logically self-defeating—were disquieting, to say the least. “
The truth is very different
from what we are inclined to believe,” the author coolly declared. But so lucid and powerful were Parfit’s arguments that the book gave rise to a veritable cottage industry of commentary in the English-speaking philosophical world. Now Parfit had turned his attention to the question that had engrossed me, the question that he himself considered to be the most “sublime” of all: why is there something rather than nothing? And he had managed to coax his thoughts on the matter into a spare, if sometimes gnomic, essay—one that I knew I had better master before meeting him.

And I
was
going to meet him. “I’m still very interested in ‘Why there is something rather than nothing,’ ” Parfit had responded when I wrote to him a few months earlier. As to the interview I proposed, he wrote, “I’m sure I’d enjoy it.” However, he added that since he was very slow in formulating his thoughts, he would prefer not to be quoted verbatim. Instead, he would try to answer any questions I had about his written work with a “yes” or “no” or some other brief response.

I spent much of that weekend in the bathtub under the roof of the Athenaeum, contentedly reading, soaking, sipping claret obligingly brought up to me by the porter from the club’s cellar, and pondering. Winston Churchill would have approved.

THERE ARE TWO
broad questions we can ask about the world:
why
it is, and
how
it is. Most of the thinkers I had encountered so far believed that the
why
question should come first. Once you know
why
the world is, they maintained, you’ll have a pretty good notion of
how
it is. Suppose, like John Leslie, or Plato and Leibniz before him, you believe that the world exists because it
ought
to exist. Then you would expect the world to be a very good world. And if the part of it you observed didn’t look especially good, you would conclude—again, like Leslie—that it must be just a tiny bit of a larger reality that, on the whole,
was
very good—
infinitely
good, in fact.

So one way of reasoning about the world is to go from
why
to
how
. But another, less obvious way is to move in the opposite direction. Suppose you look around at the world and notice that it has some special feature, one that marks it off from all of the other ways reality might have been. Perhaps, you might think, this peculiarity in
how
the world is could furnish a clue as to
why
the world is.

Going from
how
to
why
was, I discovered, the essence of Parfit’s approach. And his reversal of the usual explanatory vector made me see the mystery of existence in an entirely new light.

Think, Parfit begins, of all the different ways that reality could have turned out. One possible way, of course, is our own world—the universe that came into existence 14 billion years ago with the Big Bang. But reality might encompass more than just our world. There could be other worlds that exist in parallel with our own, even if we do not have direct access to them. And these worlds might be different in important respects from our world—in their histories, in their governing laws (or lack thereof), and in the nature of the substances that constitute them. Each of these individual worlds is what Parfit calls a “local” possibility. And the entire ensemble of individual worlds that might exist together adds up to a “cosmic” possibility.

“
Cosmic
possibilities,” Parfit says, “cover everything that ever exists, and are the different ways that the whole of reality might be. Only one such possibility can be actual, or the one that obtains.
Local
possibilities are the different ways that some part of reality, or local world, might be. If some local world exists, that leaves it open whether other worlds exist.”

So what sort of cosmic possibilities are there? Well, one cosmic possibility is that
every conceivable world exists
. Parfit calls this fullest of all realities the “All Worlds” possibility. At the other extreme is the cosmic possibility in which
no worlds at all exist
. This Parfit calls the “Null” possibility. In between the All Worlds possibility and the Null possibility range an infinity of intermediate cosmic possibilities. One of them is the possibility that all and only
good
worlds exist—that is, all worlds that are on the whole ethically better than nothing. This would be John Leslie’s “Axiarchic” possibility. Another cosmic possibility is the one in which our world and 57 other worlds similar but slightly different from it exist. One might call this the “58 Worlds” possibility. Another is that only worlds that conform to a certain set of physical laws exist—say, the laws of string theory. According to the current version of string theory, such worlds number on the order of 10 to the five-hundredth power, making up a cosmic ensemble that physicists call “the Landscape.” Still another cosmic possibility is that only those worlds that are devoid of consciousness exist. One might call this the “Zombie” possibility. And still another is that there are exactly seven worlds, each of a single color: respectively red, orange, yellow, green, blue, indigo, and violet. One might call this the “Spectrum” possibility.

The full range of such cosmic possibilities represents every way reality could have turned out. Even sheer nothingness is counted, in the form of the Null possibility. (Logical
im
possibilities, on the other hand, are
not
counted; no cosmic possibility includes a world of square circles or married bachelors.) And of all the possible ways reality could have turned out, one of them
has
to obtain.

Which raises two questions. Which of them
does
obtain? And why?

“These questions are connected,” Parfit goes on to observe. “If some possibility would be easier to explain, we have more reason to believe that this possibility obtains.”

The
least
puzzling of all of the cosmic possibilities, it would seem, is the Null possibility—that there is nothing at all. This is much the simplest possible reality, as Leibniz pointed out. It is also the only one that does not stand in need of a causal explanation. If there were no worlds at all, then no question would be raised as to what thing or force could have ushered those worlds into being.

But the Null possibility is evidently not the form reality chose to take. “In some way or another,” Parfit observes, “a Universe has managed to exist.”

And which is the least puzzling cosmic possibility that is consistent with the fact that our universe exists? That would be the All Worlds possibility: that
all
possible universes exist. “With every other cosmic possibility,” Parfit writes, “we have a further question. If ours is the only world, we can ask: ‘Out of all the possible worlds, why is this the one that exists?’ On any version of the Many Worlds Hypothesis, we have a similar question: ‘Why do just these worlds exist, with these elements and laws?’ But, if
all
these worlds exist, there is no such further question.”

The All Worlds possibility is thus the least arbitrary of the cosmic possibilities, since no local possibility is excluded. And this fullest of all possibilities could, for all we know, be the form that reality actually does take.

But what about the other cosmic possibilities? Well, if our world has a net goodness rating above zero, it might be part of the Axiarchic ensemble of worlds, whose existence would be the ethically best. Or if the laws governing our world turn out, in the final theory envisaged by Steven Weinberg, to be exceptionally elegant, then our world might be part of the most beautiful cosmic possibility. Or, if Schopenhauer and Woody Allen are right, our world might well be part of the
worst
cosmic possibility.

The point is that each of these cosmic possibilities has a special feature. The Null is the simplest, the All Worlds is the fullest, the Axiarchic is the best, and so on. Now, suppose that the cosmic possibility that actually obtains is also one that possesses such a special feature.
Perhaps that is no coincidence
. Perhaps that possibility obtains
because
it has this special feature. If that is the case, this special feature in effect
chooses
what reality is like. It is what Parfit calls “the Selector.”

Not every special feature a reality might have makes for a credible Selector. Suppose, for example, the 58 Worlds possibility mentioned earlier was how reality turned out. Now, the number 58 does have a special property: it is the smallest number that is the sum of seven different primes (2 + 3 + 5 + 7 + 11 + 13 + 17 = 58). But no one would imagine that this property could explain why reality turned out the way it did. It would be more reasonable to assume that the number of worlds merely happened to be 58. But features like
best
,
fullest
,
simplest
,
most beautiful
, and
least arbitrary
are different. If the cosmic possibility tapped to be reality had one of these features, it would be hard to think of this as simply a matter of chance. More likely, the cosmic possibility became reality
because
it had this feature.

But isn’t this use of “because” somewhat mysterious? Of course it is, Parfit admits. But even ordinary causation, he points out, is mysterious. Besides, he says, “if there is some explanation of the whole of reality, we should not expect this explanation to fit neatly into some familiar category. This extraordinary question may have an extraordinary answer.”

What Parfit had managed to do, I realized, was to reframe the mystery of existence in a way that made it vastly less mysterious. While everyone else was trying to bridge the unbridgeable gap between being and nothingness, he was running an ontological lottery. Or was it more like a beauty contest—the Miss Cosmos Pageant? The field of contestants comprised all the different ways reality could have turned out—all the cosmic possibilities. And since reality has to be some way or another, one of these cosmic possibilities is bound to prevail, as a matter of logical necessity. There is no conceivable alternative, and hence no need for any sort of “hidden machinery” to ensure that a selection is made. So the Selector, in tipping the outcome, doesn’t exert any force or do any actual work.