STEVENWEINBERG

 What About God?

From Dreams of a Final Theory

STEVEN WEINBERG

Physics, biology, genetics, paleontology, anthropology—how much more punishment can religion take from the world of science and free inquiry? Professor Weinberg earned a Nobel Prize for his work, elucidated the big bang in his wonderful book The First Three Minutes, and has vastly expanded our knowledge of subatomic particles. He poses the inescapable question and proceeds to offer some equally inescapable answers.

“You know,” said Port, and his voice sounded unreal, as voices are likely to do after a long pause in an utterly silent spot, “the sky here’s very strange. I often have the sensation when I look at it that it’s a solid thing up there, protecting us from what’s behind.”

Kit shuddered slightly as she said: “From what’s behind?”

“Yes.”

“But what is behind?” Her voice was very small.

“Nothing, I suppose. Just darkness. Absolute night.”

—PAUL BOWLES, THE SHELTERING SKY

“The heavens declare the glory of God; and the firmament showeth his handiwork.” To King David or whoever else wrote this psalm, the stars must have seemed visible evidence of a more perfect order of existence, quite different from our dull sublunary world of rocks and stones and trees. Since David’s day the sun and other stars have lost their special status; we understand that they are spheres of glowing gas, held together by gravitation, and supported against collapse by pressure that is maintained by the heat rising up from thermonuclear reactions in the stars’ cores. The stars tell us nothing more or less about the glory of God than do the stones on the ground around us.

If there were anything we could discover in nature that would give us some special insight into the handiwork of God, it would have to be the final laws of nature. Knowing these laws, we would have in our possession the book of rules that governs stars and stones and everything else. So it is natural that Stephen Hawking should refer to the laws of nature as “the mind of God.” Another physicist, Charles Misner, used similar language in comparing the perspectives of physics and chemistry: “The organic chemist, in answer to the question, ‘Why are there ninety-two elements, and when were they produced?’ may say ‘The man in the next office knows that.’ But the physicist, being asked, ‘Why is the universe built to follow certain physical laws and not others?’ may well reply, ‘God knows.’” Einstein once remarked to his assistant Ernst Straus that “What really interests me is whether God had any choice in the creation of the world.” On another occasion he described the aim of the enterprise of physics as “not only to know how nature is and how her transactions are carried through, but also to reach as far as possible the Utopian and seemingly arrogant aim of knowing why nature is thus and not otherwise…. Thereby one experiences, so to speak, that God Himself could not have arranged these connections in any other way than that which factually exists…. This is the Promethean element of the scientific experience…. Here has always been for me the particular magic of scientific effort.” Einstein’s religion was so vague that I suspect that he meant this metaphorically, as suggested by his “so to speak.” It is doubtless because physics is so fundamental that this metaphor is natural to physicists. The theologian Paul Tillich once observed that among scientists only physicists seem capable of using the word “God” without embarrassment. Whatever one’s religion or lack of it, it is an irresistible metaphor to speak of the final laws of nature in terms of the mind of God.

I encountered this connection once in an odd place, in the Rayburn House Office Building in Washington. When I testified there in 1987 in favor of the Superconducting Super Collider (SSC) project before the House Committee on Science, Space, and Technology, I described how in our study of elementary particles we are discovering laws that are becoming increasingly coherent and universal, and how we are beginning to suspect that this is not merely an accident, that there is a beauty in these laws that mirrors something that is built into the structure of the universe at a very deep level. After I made these remarks there were remarks by other witnesses and questions from members of the committee. There then ensued a dialogue between two committee members. Representative Harris W. Fawell, Republican of Illinois, who had generally been favorable to the Super Collider project, and Representative Don Ritter, Republican of Pennsylvania, a former metallurgical engineer who is one of the most formidable opponents of the project in Congress:

MR. FAWELL:…Thank you very much. I appreciate the testimony of all of you. I think it was excellent. If ever I would want to explain to one and all the reasons why the SSC is needed I am sure I can go to your testimony. It would be very helpful. I wish sometimes that we have some one word that could say it all and that is kind of impossible. I guess perhaps Dr. Weinberg you came a little close to it and I’m not sure but I took this down. You said you suspect that it isn’t all an accident, that there are rules which govern matter and I jotted down, will this make us find God? I’m sure you didn’t make that claim, but it certainly will enable us to understand so much more about the universe.

MR. RITTER: Will the gentleman yield on that? If the gentleman would yield for a moment I would say…

MR. FAWELL: I’m not sure I want to.

MR. RITTER: If this machine does that I am going to come around and support it.

I had enough sense to stay out of this exchange, because I did not think that the congressmen wanted to know what I thought about finding God at the SSC and also because it did not seem to me that letting them know what I thought about this would be helpful to the project.

Some people have views of God that are so broad and flexible that it is inevitable that they will find God wherever they look for Him. One hears it said that “God is the ultimate” or “God is our better nature” or “God is the universe.” Of course, like any other word, the word “God” can be given any meaning we like. If you want to say that “God is energy,” then you can find God in a lump of coal. But if words are to have any value to us, we ought to respect the way that they have been used historically, and we ought especially to preserve distinctions that prevent the meanings of words from merging with the meanings of other words.

In this spirit, it seems to me that if the word “God” is to be of any use, it should be taken to mean an interested God, a creator and lawgiver who has established not only the laws of nature and the universe but also standards of good and evil, some personality that is concerned with our actions, something in short that it is appropriate for us to worship.1 This is the God that has mattered to men and women throughout history. Scientists and others sometimes use the word “God” to mean something so abstract and unengaged that He is hardly to be distinguished from the laws of nature. Einstein once said that he believed in “Spinoza’s God who reveals Himself in the orderly harmony of what exists, not in a God who concerns himself with fates and actions of human beings.” But what possible difference does it make to anyone if we use the word “God” in place of “order” or “harmony,” except perhaps to avoid the accusation of having no God? Of course, anyone is free to use the word “God” in that way, but it seems to me that it makes the concept of God not so much wrong as unimportant.

Will we find an interested God in the final laws of nature? There seems something almost absurd in asking this question, not only because we do not yet know the final laws, but much more because it is difficult even to imagine being in the possession of ultimate principles that do not need any explanation in terms of deeper principles. But premature as the question may be, it is hardly possible not to wonder whether we will find any answer to our deepest questions, any sign of the workings of an interested God, in a final theory. I think that we will not.

All our experience throughout the history of science has tended in the opposite direction, toward a chilling impersonality in the laws of nature. The first great step along this path was the demystification of the heavens. Everyone knows the key figures: Copernicus, who proposed that the earth is not at the center of the universe; Galileo, who made it plausible that Copernicus was right; Bruno, who guessed that the sun is only one of a vast number of stars; and Newton, who showed that the same laws of motion and gravitation apply to the solar system and to bodies on the earth. The key moment I think was Newton’s observation that the same law of gravitation governs the motion of the moon around the earth and a falling body on the surface of the earth. In our own century the demystification of the heavens was taken a step farther by the American astronomer Edwin Hubble. By measuring the distance to the Andromeda Nebula, Hubble showed that this, and by inference thousands of other similar nebulas, were not just outlying parts of our galaxy but galaxies in their own right, quite as impressive as our own. Modern cosmologists even speak of a Copernican principle: the rule that no cosmological theory can be taken seriously that puts our own galaxy at any distinctive place in the universe.

Life, too, has been demystified. Justus von Liebig and other organic chemists in the early nineteenth century demonstrated that there was no barrier to the laboratory synthesis of chemicals like uric acid that are associated with life. Most important of all were Charles Darwin and Alfred Russel Wallace, who showed how the wonderful capabilities of living things could evolve through natural selection with no outside plan or guidance. The process of demystification has accelerated in this century, in the continued success of biochemistry and molecular biology in explaining the workings of living things.

The demystification of life has had a far greater effect on religious sensibilities than has any discovery of physical science. It is not surprising that it is reductionism in biology and the theory of evolution rather than the discoveries of physics and astronomy that continue to evoke the most intransigent opposition.

Even from scientists one hears occasional hints of vitalism, the belief in biological processes that cannot be explained in terms of physics and chemistry. In this century biologists (including antireductionists like Ernst Mayr) have generally steered clear of vitalism, but as late as 1944 Erwin Schrodinger argued in his well-known book What Is Life? that “enough is known about the material structure of life to tell exactly why present-day physics cannot account for life.” His reason was that the genetic information that governs living organisms is far too stable to fit into the world of continual fluctuations described by quantum mechanics and statistical mechanics. Schrodinger’s mistake was pointed out by Max Perutz, the molecular biologist who among other things worked out the structure of hemoglobin: Schrodinger had ignored the stability that can be produced by the chemical process known as enzymatic catalysis.

The most respectable academic critic of evolution may currently be Professor Phillip Johnson of the University of California School of Law. Johnson concedes that evolution has occurred and that it is sometimes due to natural selection, but he argues that there is no “incontrovertible experimental evidence” that evolution is not guided by some divine plan. Of course, one could never hope to prove that no supernatural agency ever tips the scales in favor of some mutations and against others. But much the same could be said of any scientific theory. There is nothing in the successful application of Newton’s or Einstein’s laws of motion to the solar system that prevents us from supposing that every once in a while some comet gets a small shove from a divine agency. It seems pretty clear that Johnson raises this issue not as a matter of impartial open-mindedness but because for religious reasons he cares very much about life in a way that he does not care about comets. But the only way that any sort of science can proceed is to assume that there is no divine intervention and to see how far one can get with this assumption.

Johnson argues that naturalistic evolution, “evolution that involves no intervention or guidance by a creator outside the world of nature,” in fact does not provide a very good explanation for the origin of species. I think he goes wrong here because he has no feeling for the problems that any scientific theory always has in accounting for what we observe. Even apart from outright errors, our calculations and observations are always based on assumptions that go beyond the validity of the theory we are trying to test. There never was a time when the calculations based on Newton’s theory of gravitation or any other theory were in perfect agreement with all observations. In the writings of today’s paleontologists and evol tionary biologists we can recognize the same state of affairs that is so familiar to us in physics; in using the naturalistic theory of evolution biologists are working with an overwhelmingly successful theory, but one that is not yet finished with its work of explication. It seems to me to be a profoundly important discovery that we can get very far in explaining the world without invoking divine intervention, and in biology as well as in the physical sciences.

In another respect I think that Johnson is right. He argues that there is an incompatibility between the naturalistic theory of evolution and religion as generally understood, and he takes to task the scientists and educators who deny it. He goes on to complain that “naturalistic evolution is consistent with the existence of ‘God’ only if by that term we mean no more than a first cause which retires from further activity after establishing the laws of nature and setting the natural mechanism in motion.”

The inconsistency between the modern theory of evolution and belief in an interested God does not seem to me one of logic—one can imagine that God established the laws of nature and set the mechanism of evolution in motion with the intention that through natural selection you and I would someday appear—but there is a real inconsistency in temperament. After all, religion did not arise in the minds of men and women who speculated about infinitely prescient first causes but in the hearts of those who longed for the continual intervention of an interested God.

The religious conservatives understand, as their liberal opponents seem often not to, how high the stakes are in the debate over teaching evolution in the public schools. In 1983, shortly after coming to Texas, I was invited to testify before a committee of the Texas Senate on a regulation that forbade the teaching of the theory of evolution in state-purchased high-school textbooks unless equal emphasis was given to creationism. One of the members of the committee asked me how the state could support the teaching of a scientific theory like evolution that was so corrosive of religious belief. I replied that just as it would be wrong for those who are emotionally committed to atheism to give evolution more emphasis than would be otherwise appropriate in teaching biology, so it would be inconsistent with the First Amendment to give evolution less emphasis as a means of protecting religious belief. It is simply not the business of the public schools to concern themselves one way or the other with the religious implications of scientific theories. My answer did not satisfy the senator because he knew as I did what would be the effect of a course in biology that gives an appropriate emphasis to the theory of evolution. As I left the committee room, he muttered that “God is still in heaven anyway.” Maybe so, but we won that battle; Texas high-school textbooks are now not only allowed but required to teach the modern theory of evolution, and with no nonsense about creationism. But there are many places (today especially in Islamic countries) where this battle is yet to be won and no assurance anywhere that it will stay won.

One often hears that there is no conflict between science and religion. For instance, in a review of Johnson’s book, Stephen Gould remarks that science and religion do not come into conflict, because “science treats factual reality, while religion treats human morality.” On most things I tend to agree with Gould, but here I think he goes too far; the meaning of religion is defined by what religious people actually believe, and the great majority of the world’s religious people would be surprised to learn that religion has nothing to do with factual reality.

But Gould’s view is widespread today among scientists and religious liberals. This seems to me to represent an important retreat of religion from positions it once occupied. Once nature seemed inexplicable without a nymph in every brook and a dryad in every tree. Even as late as the nineteenth century the design of plants and animals was regarded as visible evidence of a creator. There are still countless things in nature that we cannot explain, but we think we know the principles that govern the way they work. Today, for real mystery, one has to look to cosmology and elementary particle physics. For those who see no conflict between science and religion, the retreat of religion from the ground occupied by science is nearly complete.

Judging from this historical experience, I would guess that, though we shall find beauty in the final laws of nature, we will find no special status for life or intelligence. A fortiori, we will find no standards of value or morality. And so we will find no hint of any God who cares about such things. We may find these things elsewhere, but not in the laws of nature.

I have to admit that sometimes nature seems more beautiful than strictly necessary. Outside the window of my home office there is a hackberry tree, visited frequently by a convocation of politic birds: blue jays, yellow-throated vireos, and, loveliest of all, an occasional red cardinal. Although I understand pretty well how brightly colored feathers evolved out of a competition for mates, it is almost irresistible to imagine that all this beauty was somehow laid on for our benefit. But the God of birds and trees would have to be also the God of birth defects and cancer.

Religious people have grappled for millennia with the theodicy, the problem posed by the existence of suffering in a world that is supposed to be ruled by a good God. They have found ingenious solutions in terms of various supposed divine plans. I will not try to argue with these solutions, much less to add one more of my own. Remembrance of the Holocaust leaves me unsympathetic to attempts to justify the ways of God to man. If there is a God that has special plans for humans, then He has taken very great pains to hide His concern for us. To me it would seem impolite if not impious to bother such a God with our prayers.

Not all scientists would agree with my bleak view of the final laws. I do not know of anyone who maintains explicitly that there is scientific evidence for a divine being, but several scientists do argue for a special status in nature for intelligent life. Of course, everyone knows that as a practical matter biology and psychology have to be studied in their own terms, not in terms of elementary particle physics, but that is not a sign of any special status for life or intelligence; the same is true of chemistry and hydrodynamics. If, on the other hand, we found some special role for intelligent life in the final laws at the point of convergence of the arrows of explanation, we might well conclude that the creator who established these laws was in some way specially interested in us.

John Wheeler is impressed by the fact that, according to the standard Copenhagen interpretation of quantum mechanics, a physical system cannot be said to have any definite values for quantities like position or energy or momentum until these quantities are measured by some observer’s apparatus. For Wheeler, some sort of intelligent life is required in order to give meaning to quantum mechanics. Recently Wheeler has gone further and proposed that intelligent life not only must appear but must go on to pervade every part of the universe in order that every bit of information about the physical state of the universe should eventually be observed. Wheeler’s conclusions seem to me to provide a good example of the dangers of taking too seriously the doctrine of positivism, that science should concern itself only with things that can be observed. Other physicists including myself prefer another, realist, way of looking at quantum mechanics, in terms of a wave function that can describe laboratories and observers as well as atoms and molecules, governed by laws that do not materially depend on whether there are any observers or not.

Some scientists make much of the fact that some of the fundamental constants have values that seem remarkably well suited to the appearance of intelligent life in the universe. It is not yet clear whether there is anything to this observation, but even if there is, it does not necessarily imply the operation of a divine purpose. In several modern cosmological theories, the so-called constants of nature (such as the masses of the elementary particles) actually vary from place to place or from time to time or even from one term in the wave function of the universe to another. If that were true, then as we have seen, any scientists who study the laws of nature would have to be living in a part of the universe where the constants of nature take values favorable for the evolution of intelligent life.

For an analogy, suppose that there is a planet called Earthprime, in every respect identical to our own, except that on this planet mankind developed the science of physics without knowing anything about astronomy. (E.g., one might imagine that Earthprime’s surface is perpetually covered by clouds.) Just as on earth, students on Earthprime would find tables of fundamental constants at the back of their physics textbooks. These tables would list the speed of light, the mass of the electron, and so on, and also another “fundamental” constant having the value 1.99 calories of energy per minute per square centimeter, which gives the energy reaching Earthprime’s surface from some unknown source outside. On earth this is called the solar constant because we know that this energy comes from the sun, but no one on Earthprime would have any way of knowing where this energy comes from or why this constant takes this particular value. Some physicist on Earthprime might note that the observed value of this constant is remarkably well suited to the appearance of life. If Earthprime received much more or much less than two calories per minute per square centimeter the water of the oceans would instead be vapor or ice, leaving Earthprime with no liquid water or reasonable substitute in which life could have evolved. The physicist might conclude that this constant of 1.99 calories per minute per square centimeter had been fine-tuned by God for man’s benefit. More skeptical physicists on Earthprime might argue that such constants are eventually going to be explained by the final laws of physics, and that it is just a lucky accident that they have values favorable for life. In fact, both would be wrong. When the inhabitants of Earthprime finally develop a knowledge of astronomy, they learn that their planet receives 1.99 calories per minute per square centimeter because, like earth, it happens to be about 93 million miles away from a sun that produces 5,600 million million million million calories per minute, but they also see that there are other planets closer to their sun that are too hot for life and more planets farther from their sun that are too cold for life and doubtless countless other planets orbiting other stars of which only a small proportion are suitable for life. When they learn something about astronomy, the arguing physicists on Earthprime finally understand that the reason why they live on a world that receives roughly two calories per minute per square centimeter is just that there is no other kind of world where they could live. We in our part of the universe may be like the inhabitants of Earthprime before they learn about astronomy, but with other parts of the universe instead of other planets hidden from our view.

I would go further. As we have discovered more and more fundamental physical principles, they seem to have less and less to do with us. To take one example, in the early 1920s it was thought that the only elementary particles were he electron and the proton, then considered to be the ingredients from which we and our world are made. When new particles like the neutron were discovered it was taken for granted at first that they had to be made up of electrons and protons. Matters are very different today. We are not so sure anymore what we mean by a particle being elementary, but we have learned the important lesson that the fact that particles are present in ordinary matter has nothing to do with how fundamental they are. Almost all the particles whose fields appear in the modern standard model of particles and interactions decay so rapidly that they are absent in ordinary matter and play no role at all in human life. Electrons are an essential part of our everyday world; the particles called muons and tauons hardly matter at all to our lives; yet, in the way that they appear in our theories, electrons do not seem in any way more fundamental than muons and tauons. More generally, no one has ever discovered any correlation between the importance of anything to us and its importance in the laws of nature.

Of course it is not from the discoveries of science that most people would have expected to learn about God anyway. John Polkinghorne has argued eloquently for a theology “placed within an area of human discourse where science also finds a home” that would be based on religious experience such as revelation, in much the way that science is based on experiment and observation. Those who think that they have had religious experiences of their own have to judge for themselves the quality of that experience. But the great majority of the adherents to the world’s religions are relying not on religious experience of their own but on revelations that were supposedly experienced by others. It might be thought that this is not so different from the theoretical physicist relying on the experiments of others, but there is a very important distinction. The insights of thousands of individual physicists have converged to a satisfying (though incomplete) common understanding of physical reality. In contrast, the statements about God or anything else that have been derived from religious revelation point in radically different directions. After thousands of years of theological analysis, we are no closer now to a common understanding of the lessons of religious revelation.

There is another distinction between religious experience and scientific experiment. The lessons of religious experience can be deeply satisfying, in contrast to the abstract and impersonal worldview gained from scientific investigation. Unlike science, religious experience can suggest a meaning for our lives, a part for us to play in a great cosmic drama of sin and redemption, and it holds out to us a promise of some continuation after death. For just these reasons, the lessons of religious experience seem to me indelibly marked with the stamp of wishful thinking.

In my 1977 book, The First Three Minutes, I was rash enough to remark that “the more the universe seems comprehensible, the more it seems pointless.” I did not mean that science teaches us that the universe is pointless, but rather that the universe itself suggests no point. I hastened to add that there were ways that we ourselves could invent a point for our lives, including trying to understand the universe. But the damage was done: that phrase has dogged me ever since. Recently Alan Lightman and Roberta Brawer published interviews with twenty-seven cosmologists and physicists, most of whom had been asked at the end of their interview what they thought of that remark. With various qualifications, ten of the interviewees agreed with me and thirteen did not, but of those thirteen, three disagreed because they did not see why anyone would expect the universe to have a point. The Harvard astronomer Margaret Geller asked, “Why should it have a point What point? It’s just a physical system, what point is there? I’ve always been puzzled by that statement.” The Princeton astrophysicist Jim Peebles remarked, “I’m willing to believe that we are flotsam and jetsam.” (Peebles also guessed that I had had a bad day.) Another Princeton astrophysicist, Edwin Turner, agreed with me but suspected that I had intended the remark to annoy the reader. My favorite response was that of my colleague at the University of Texas, the astronomer Gerard de Vaucouleurs. He said that he thought my remark was “nostalgic.” Indeed it was—nostalgic for a world in which the heavens declared the glory of God.

About a century and a half ago Matthew Arnold found in the withdrawing ocean tide a metaphor for the retreat of religious faith, and heard in the water’s sound “the note of sadness.” It would be wonderful to find in the laws of nature a plan prepared by a concerned creator in which human beings played some special role. I find sadness in doubting that we will. There are some among my scientific colleagues who say that the contemplation of nature gives them all the spiritual satisfaction that others have traditionally found in a belief in an interested God. Some of them may even really feel that way. I do not. And it does not seem to me to be helpful to identify the laws of nature as Einstein did with some sort of remote and disinterested God. The more we refine our understanding of God to make the concept plausible, the more it seems pointless.

Among today’s scientists I am probably somewhat atypical in caring about such things. On the rare occasions when conversations over lunch or tea touch on matters of religion, the strongest reaction expressed by most of my fellow physicists is a mild surprise and amusement that anyone still takes all that seriously. Many physicists maintain a nominal affiliation with the faith of their parents, as a form of ethnic identification and for use at weddings and funerals, but few of these physicists seem to pay any attention to their nominal religion’s theology. I do know two general relativists who are devout Roman Catholics; several theoretical physicists who are observant Jews; an experimental physicist who is a born-again Christian; one theoretical physicist who is a dedicated Muslem; and one mathematical physicist who has taken holy orders in the Church of England. Doubtless there are other deeply religious physicists whom I don’t know or who keep their opinions to themselves. But, as far as I can tell from my own observations, most physicists today are not sufficiently interested in religion even to qualify as practicing atheists.

Religious liberals are in one sense even farther in spirit from scientists than are fundamentalists and other religious conservatives. At least the conservatives, like the scientists, tell you that they believe in what they believe because it is true, rather than because it makes them good or happy. Many religious liberals today seem to think that different people can believe in different mutually exclusive things without any of them being wrong, as long as their beliefs “work for them.” This one believes in reincarnation, that one in heaven and hell; a third believes in the extinction of the soul at death, but no one can be said to be wrong as long as everyone gets a satisfying spiritual rush from what they believe. To borrow a phrase from Susan Sontag, we are surrounded by “piety without content.” It all reminds me of a story that is told about an experience of Bertrand Russell, when in 1918 he was committed to prison for his opposition to the war. Following prison routine, a jailer asked Russell his religion, and Russell said that he was an agnostic. The jailer looked puzzled for a moment, and then brightened, with the observation that “I guess it’s all right. We all worship the same God, don’t we?”

Wolfgang Pauli was once asked whether he thought that a particularly ill-conceived physics paper was wrong. He replied that such a description would be too kind—the paper was not even wrong. I happen to think that the religious conservatives are wrong in what they believe, but at least they have not forgotten what it means really to believe something. The religious liberals seem to me to be not even wrong.

One often hears that theology is not the important thing about religion—the important thing is how it helps us to live. Very strange, that the existence and nature of God and grace and sin and heaven and hell are not important! I would guess that people do not find the theology of their own supposed religion important because they cannot bring themselves to admit that they do not believe any of it. But throughout history and in many parts of the world today people have believed in one theology or another, and for them it has been very important. One may be put off by the intellectual muzziness of religious liberalism, but it is conservative dogmatic religion that does the harm. Of course it has also made great moral and artistic contributions. This is not the place to argue how we should strike a balance between these contributions of religion on one hand and the long cruel story of crusade and jihad and inquisition and pogrom on the other. But I do want to make the point that in striking this balance, it is not safe to assume that religious persecution and holy wars are perversions of true religion. To assume that they are seems to me a symptom of a widespread attitude toward religion, consisting of deep respect combined with a profound lack of interest. Many of the great world religions teach that God demands a particular faith and form of worship. It should not be surprising that some of the people who take these teachings seriously should sincerely regard these divine commands as incomparably more important than any merely secular virtues like tolerance or compassion or reason.

Across Asia and Africa the dark forces of religious enthusiasm are gathering strength, and reason and tolerance are not safe even in the secular states of the West. The historian Hugh Trevor-Roper has said that it was the spread of the spirit of science in the seventeenth and eighteenth centuries that finally ended the burning of witches in Europe. We may need to rely again on the influence of science to preserve a sane world. It is not the certainty of scientific knowledge that fits it for this role, but its uncertainty. Seeing scientists change their minds again and again about matters that can be studied directly in laboratory experiments, how can one take seriously the claims of religious tradition or sacred writings to certain knowledge about matters beyond human experience?

Of course, science has made its own contribution to the world’s sorrows, but generally by giving us the means of killing each other, not the motive. Where the authority of science has been invoked to justify horrors, it really has been in terms of perversions of science, like Nazi racism and “eugenics.” As Karl Popper has said, “It is only too obvious that it is irrationalism and not rationalism that has the responsibility for all national hostility and aggression, both before and after the Crusades, but I do not know of any war waged for a ‘scientific’ aim, and inspired by scientists.”

Unfortunately I do not think that it is possible to make the case for scientific modes of reasoning by rational argument. David Hume saw long ago that in appealing to our past experience of successful science we are assuming the validity of the very mode of reasoning we are trying to justify. In the same way, all logical arguments can be defeated by the simple refusal to reason logically. So we cannot simply dismiss the question why, if we do not find the spiritual comfort we want in the laws of nature, we should not look for it elsewhere—in spiritual authority of one sort or another, or in an independent leap of faith?

The decision to believe or not is not entirely in our hands. I might be happier and have better manners if I thought I were descended from the emperors of China, but no effort of will on my part can make me believe it, any more than I can will my heart to stop beating. Yet it seems that many people are able to exert some control over what they believe and choose to believe in what they think makes them good or happy. The most interesting description I know of how this control can work appears in George Orwell’s novel 1984. The hero, Winston Smith, has written in his diary that “freedom is the freedom to say that two plus two is four.” The inquisitor, O’Brien, takes this as a challenge, and sets out to force Smith to change his mind. Under torture Smith is perfectly willing to say that two plus two is five, but that is not what O’Brien is after. Finally, the pain becomes so unbearable that in order to escape it Smith manages to convince himself for an instant that two plus two is five. O’Brien is satisfied for the moment, and the torture is suspended. In much the same way, the pain of confronting the prospect of our own deaths and the deaths of those we love impels us to adopt beliefs that soften that pain. If we are able to manage to adjust our beliefs in this way, then why not do so?

I can see no scientific or logical reason not to seek consolation by adjustment of our beliefs—only a moral one, a point of honor. What do we think of someone who has managed to convince himself that he is bound to win a lottery because he desperately needs the money? Some might envy him his brief great expectations, but many others would think that he is failing in his proper role as an adult and rational human being, of looking at things as they are. In the same way that each of us has had to learn in growing up to resist the temptation of wishful thinking about ordinary things like lotteries, so our species has had to learn in growing up that we are not playing a starring role in any sort of grand cosmic drama.

Nevertheless, I do not for a minute think that science will ever provide the consolations that have been offered by religion in facing death. The finest statement of this existential challenge that I know is found in The Ecclesiastical History of the English, written by the Venerable Bede sometime around A.D. 700. Bede tells how King Edwin of Northumbria held a council in A.D. 627 to decide on the religion to be accepted in his kingdom, and gives the following speech to one of the king’s chief men:

Your majesty, when we compare the present life of man on earth with that time of which we have no knowledge, it seems to me like the swift flight of a single sparrow through the banqueting-hall where you are sitting at dinner on a winter’s day with your thanes and counsellors. In the midst there is a comforting fire to warm the hall; outside, the storms of winter rain or snow are raging. This sparrow flies swiftly in through one door of the hall, and out through another. While he is inside, he is safe from the winter storms; but after a few moments of comfort, he vanishes from sight into the wintry world from which he came. Even so, man appears on earth for a little while; but of what went before this life or of what follows, we know nothing.

It is an almost irresistible temptation to believe with Bede and Edwin that there must be something for us outside the banqueting hall. The honor of resisting this temptation is only a thin substitute for the consolations of religion, but it is not entirely without satisfactions of its own.