How far can we go—in science, mathematics, technology, medicine, the arts, even politics? Can our efforts in these fields advance indefinitely? Or will they eventually bump into limits? I have a weakness for such impossibly grand questions, and so, I was happy to discover, does the British physicist David Deutsch.
Mr. Deutsch has earned notice for his vigorous advocacy of the many-worlds interpretation of quantum mechanics—the idea that, although we see a particle follow only one path in our world, it actually follows all possible paths in other universes.
Mr. Deutsch touches on this and other esoteric concepts in “The Beginning of Infinity,” but his book is animated by an ambition much greater than defending a particular theory. Mr. Deutsch wants us to share his radically optimistic vision of humanity’s future, one in which progress continues forever.
I’m not a fan of “multiverse” theories, which I think of as science fiction with equations. And Mr. Deutsch knocks my 1996 book, “The End of Science,” for proposing that the glory days of science—especially pure science, the effort to map out and understand reality—may be over.
Mr. Deutsch equates my thesis with “dogmatism, stagnation and tyranny,” all of which, for the record, I oppose. But he makes the case for infinite progress with such passion, imagination and quirky brilliance that I couldn’t help enjoying his argument. More often than not I found myself agreeing with him—or at least hoping that he is right.
Mr. Deutsch notes that for most of history—apart from a few shining exceptions, such as Athens in the time of Pericles—knowledge scarcely evolved. Conformity reigned, and innovation was suppressed. But several centuries ago, Enlightenment figures such as Galileo, Newton and Voltaire helped propagate a powerful way of solving problems: propose an explanation of reality, test it and criticize it, pose a new and improved explanation, test and criticize that one, and so on.
Through this process we began to accumulate insight into nature, an achievement embodied by the scientific and industrial revolutions. We also advanced in the political realm, replacing archaic forms of governance with more just, representational systems.
The greatest threat to continued progress, Mr. Deutsch contends, is our belief that we can achieve—or, worse, have already achieved—ultimate solutions. We must accept that we are fallible, he says, and hence that our knowledge is tentative and improvable no matter how definitive it may seem at the moment.
He rejects end-points of all kinds, whether a “theory of everything” that answers every scientific riddle, a work of art so exquisite that it cannot be surpassed or even the Buddhist version of Enlightenment, a state of unsurpassable spiritual grace.
If we acknowledge our imperfections, Mr. Deutsch observes, then, paradoxically, there is no problem that we cannot tackle. Death, for instance. Or the apparent incompatibility between the two pillars of modern physics, quantum theory and general relativity.
Or global warming, which Mr. Deutsch believes we can overcome through innovation rather than drastic cutbacks in consumption. He gores the sacred cow of “sustainability”: Societies are healthiest, he declares, not when they achieve equilibrium but when they are rapidly evolving.
Making the case for science’s open-endedness, Mr. Deutsch mounts a compelling challenge to scientific reductionism, which explains all phenomena in terms of their physical components. Yes, atomic theory, chemistry and genetics have worked spectacularly well at explaining many features of nature. But small-scale processes, the author notes, spawn so-called emergent phenomena that require understanding on their own terms.
Bodies give rise to minds, which in turn give rise to ideas, which have no specific physical properties but can nonetheless influence human behaviour in profound ways, as the Enlightenment itself demonstrates.
Mr. Deutsch’s emphasis on the nonmaterial qualities of the mind dovetails with his insistence that progress stems, above all, from human creativity. Although we are subject to the laws of nature, he says, we can control our destiny through our own free choices.
This might not seem like a terribly controversial claim, but many leading scientists—from Albert Einstein and Francis Crick to Stephen Hawking—have argued that free will is an illusion, because our “choices” are pre-determined by physical processes beyond our conscious control. I am heartened that Mr. Deutsch resists this appalling scientific determinism.
“The Beginning of Infinity” is, as Mr. Deutsch’s own argument would stipulate, imperfect. He rejects appeals to authority but constantly defers to the philosopher Karl Popper, who can be a weirdly dogmatic opponent of dogmatism. And Mr. Deutsch’s optimism sometimes resembles that of a man standing on a mountaintop, high above the problems afflicting us ordinary folk in the lowlands.
Physics, for example, has stalled not for lack of a can-do spirit, as the author implies, but for mundane reasons: Society is reluctant to build the gigantic, expensive accelerators that might help physicists forge past current theories. It is true that neuroscience has the potential to yield discoveries of revolutionary import, but neuroscientists have yet to crack the code of the brain, which becomes more dauntingly complex as we learn more about it.
So when it comes to science it is easy to see limits where Mr. Deutsch sees boundless opportunities. But he has persuaded me that we can solve many of our problems as long as we don’t assume that we know more than we do. And, given a choice, why not choose hope?