[I]gnorance more frequently begets confidence than does knowledge: it is those who know little, and not those who know much, who so positively a.s.sert that this or that problem will never be solved by science.

Charles Darwin, Introduction, The Descent of Man The Descent of Man (1871) (1871)

By 'Newton's sleep', the poet, painter and revolutionary William Blake seems to have meant a tunnel vision in the perspective of Newton's physics, as well as Newton's own (incomplete) disengagement from mysticism. Blake thought the idea of atoms and particles of light amusing, and Newton's influence on our species 'satanic'. A common critique of science is that it is too narrow. Because of our well-demonstrated fallibilities, it rules out of court, beyond serious discourse, a wide range of uplifting images, playful notions, earnest mysticism and stupefying wonders. Without physical evidence, science does not admit spirits, souls, angels, devils or dharma bodies of the Buddha. Or alien visitors.

The American psychologist Charles Tart, who believes the evidence for extrasensory perception is convincing, writes: An important factor in the current popularity of 'New Age' ideas is a reaction against the dehumanizing, despiritualizing effects otscientism, otscientism, the philosophical belief (masquerading as objective science and held with the emotional tenacity of born-again fundamentalism) that we are the philosophical belief (masquerading as objective science and held with the emotional tenacity of born-again fundamentalism) that we are nothing but nothing but material beings. To unthinkingly embrace anything and everything labeled 'spiritual' or 'psychic' or 'New Age' is, of course, foolish, for many of these ideas are factually wrong, however n.o.ble or inspiring they are. On the other hand, this New Age interest is a legitimate recognition of some of the realities of human nature: People have always had and continue to have experiences that seem to be 'psychic' or 'spiritual'. material beings. To unthinkingly embrace anything and everything labeled 'spiritual' or 'psychic' or 'New Age' is, of course, foolish, for many of these ideas are factually wrong, however n.o.ble or inspiring they are. On the other hand, this New Age interest is a legitimate recognition of some of the realities of human nature: People have always had and continue to have experiences that seem to be 'psychic' or 'spiritual'.

But why should 'psychic' experiences challenge the idea that we are made of matter and nothing but? There is very little doubt that, in the everyday world, matter (and energy) exist. The evidence is all around us. In contrast, as I've mentioned earlier, the evidence for something non-material called 'spirit' or 'soul' is very much in doubt. Of course each of us has a rich internal life. Considering the stupendous complexity of matter, though, how could we possibly prove that our internal life is not wholly due to matter? Granted, there is much about human consciousness that we do not fully understand and cannot yet explain in terms of neurobiology. Humans have limitations, and no one knows this better than scientists. But a mult.i.tude of aspects of the natural world that were considered miraculous only a few generations ago are now thoroughly understood in terms of physics and chemistry. At least some of the mysteries of today will be comprehensively solved by our descendants. The fact that we cannot now produce a detailed understanding of, say, altered states of consciousness in terms of brain chemistry no more implies the existence of a 'spirit world' than a sunflower following the Sun in its course across the sky was evidence of a literal miracle before we knew about phototropism and plant hormones. And if the world does not in all respects correspond to our wishes, is this the fault of science, or of those who would impose their wishes on the world? All the mammals - and many other animals as well - experience emotions: fear, l.u.s.t, hope, pain, love, hate, the need to be led. Humans may brood about the future more, but there is nothing in our emotions unique to us. On the other hand, no other species does science as much or as well as we. How then can science be 'dehumanizing'?

Still, it seems so unfair: some of us starve to death before we're out of infancy, while others - by an accident of birth - live out their lives in opulence and splendour. We can be born into an abusive family or a reviled ethnic group, or start out with some deformity; we go through life with the deck stacked against us, and then we die, and that's it? Nothing but a dreamless and endless sleep? Where's the justice in this? This is stark-and brutal and heartless. Shouldn't we have a second chance on a level playing field? How much better if we were born again in circ.u.mstances that took account of how well we played our part in the last life, no matter how stacked against us the deck was then. Or if there were a time of judgement after we die, then - so long as we did well with the persona we were given in this life, and were humble and faithful and all the rest - we should be rewarded by living joyfully until the end of time in a permanent refuge from the agony and turmoil of the world. That's how it would be if the world were thought out, preplanned, fair. That's how it would be if those suffering from pain and torment were to receive the consolation they deserve.

So societies that teach contentment with our present station in life, in expectation of post mortem of post mortem reward, tend to inoculate themselves against revolution. Further, fear of death, which in some respects is adaptive in the evolutionary struggle for existence, is maladaptive in warfare. Those cultures that teach an afterlife of bliss for heroes - or even for those who just did what those in authority told them - might gain a compet.i.tive advantage. reward, tend to inoculate themselves against revolution. Further, fear of death, which in some respects is adaptive in the evolutionary struggle for existence, is maladaptive in warfare. Those cultures that teach an afterlife of bliss for heroes - or even for those who just did what those in authority told them - might gain a compet.i.tive advantage.

Thus, the idea of a spiritual part of our nature that survives death, the notion of an afterlife, ought to be easy for religions and nations to sell. This is not an issue on which we might antic.i.p.ate widespread scepticism. People will want to believe it, even if the evidence is meagre to nil. True, brain lesions can make us lose major segments of our memory, or convert us from manic to placid, or vice versa; and changes in brain chemistry can convince us there's a ma.s.sive conspiracy against us, or make us think we hear the Voice of G.o.d. But as compelling testimony as this provides that our personality, character, memory - if you will, soul - resides in the matter of the brain, it is easy not to focus on it, to find ways to evade the weight of the evidence.

And if there are powerful social inst.i.tutions insisting that there is is an afterlife, it should be no surprise that dissenters tend to be spa.r.s.e, quiet and resented. Some Eastern, Christian and New Age religions, as well as Platonism, hold that the world is unreal, that suffering, death and matter itself are illusions; and that nothing really exists except 'Mind'. In contrast, the prevailing scientific view is that the mind is how we perceive what the brain does; i.e., it's a property of the hundred trillion neural connections in the brain. an afterlife, it should be no surprise that dissenters tend to be spa.r.s.e, quiet and resented. Some Eastern, Christian and New Age religions, as well as Platonism, hold that the world is unreal, that suffering, death and matter itself are illusions; and that nothing really exists except 'Mind'. In contrast, the prevailing scientific view is that the mind is how we perceive what the brain does; i.e., it's a property of the hundred trillion neural connections in the brain.

There is a strangely waxing academic opinion, with roots in the 1960s, that holds all views to be equally arbitrary and 'true' or 'false' to be a delusion. Perhaps it is an attempt to turn the tables on scientists who have long argued that literary criticism, religion, aesthetics, and much of philosophy and ethics are mere subjective opinion, because they cannot be demonstrated like a theorem in Euclidean geometry nor put to experimental test.

There are people who want everything to be possible, to have their reality unconstrained. Our imagination and our needs require more, they feel, than the comparatively little that science teaches we may be reasonably sure of. Many New Age gurus - the actress Shirley MacLaine among them - go so far as to embrace solipsism, to a.s.sert that the only reality is their own thoughts. 'I am G.o.d,' they actually say. 'I really think we are creating our own reality,' MacLaine once told a sceptic. 'I think I'm creating you right here.'

If I dream of being reunited with a dead parent or child, who is to tell me that it didn't really really happen? If 1 have a vision of myself floating in s.p.a.ce looking down on the Earth, maybe I was really there; who are some scientists, who didn't even share the experience, to tell me that it's all in my head? If my religion teaches that it is the inalterable and inerrant word of G.o.d that the Universe is a few thousand years old, then scientists are being offensive and impious, as well as mistaken, when they claim it's a few billion. happen? If 1 have a vision of myself floating in s.p.a.ce looking down on the Earth, maybe I was really there; who are some scientists, who didn't even share the experience, to tell me that it's all in my head? If my religion teaches that it is the inalterable and inerrant word of G.o.d that the Universe is a few thousand years old, then scientists are being offensive and impious, as well as mistaken, when they claim it's a few billion.

Irritatingly, science claims to set limits on what we can do, even in principle. Who says we can't travel faster than light? They used to say that about sound, didn't they? Who's going to stop us, if we have really powerful instruments, from measuring the position and the momentum of an electron simultaneously? Why can't we, if we're very clever, build a perpetual motion machine 'of the first kind' (one that generates more energy than is supplied to it), or a perpetual motion machine 'of the second kind' (one that never runs down)? Who dares to set limits on human ingenuity?

In fact, Nature does. In fact, a fairly comprehensive and very brief statement of the laws of Nature, of how the Universe works, is contained in just such a list of prohibited acts. Tellingly, pseudoscience and superst.i.tion tend to recognize no constraints in Nature. Instead, 'all things are possible'. They promise a limitless production budget, however often their adherents have been disappointed and betrayed.

A related complaint is that science is too simple-minded, too 'reductionist'; it naively imagines that in the final accounting there will be only a few laws of Nature - perhaps even rather simple ones - that explain everything, that the exquisite subtlety of the world, all the snow crystals, spiderweb latticework, spiral galaxies, and flashes of human insight can ultimately be 'reduced' to such laws. Reductionism seems to pay insufficient respect to the complexity of the Universe. It appears to some as a curious hybrid of arrogance and intellectual laziness.

To Isaac Newton - who in the minds of critics of science personifies 'single vision' - it looked like a clockwork Universe. Literally. The regular, predictable orbital motions of the planets around the Sun, or the Moon around the Earth, were described to high precision by essentially the same differential equation that predicts the swing of a pendulum or the oscillation of a spring. We have a tendency today to think we occupy some exalted vantage point, and to pity the poor Newtonians for having so limited a world view. But within certain reasonable limitations, the same harmonic equations that describe clockwork really do describe the motions of astronomical objects throughout the Universe. This is a profound, not a trivial parallelism.

Of course, there are no gears in the solar system, and the component parts of the gravitational clockwork do not touch. Planets generally have more complicated motions than pendulums and springs. Also, the clockwork model breaks down in certain circ.u.mstances: over very long periods of time, the gravitational tugs of distant worlds - tugs that might seem wholly insignificant over a few orbits - can build up, and some little world can go unexpectedly careening out of its accustomed course. However, something like chaotic motion is also known in pendulum clocks; if we displace the bob too far from the perpendicular, a wild and ugly motion ensues. But the solar system keeps better time than any mechanical clock, and the whole idea of keeping time comes from the observed motion of the Sun and stars.

The astonishing fact is that similar mathematics applies so well to planets and to clocks. It needn't have been this way. We didn't impose it on the Universe. That's the way the Universe is. If this is reductionism, so be it.

Until the middle twentieth century, there had been a strong belief - among theologians, philosophers and many biologists -that life was not 'reducible' to the laws of physics and chemistry, that there was a 'vital force', an 'entelechy', a tao, a mana that made living things go. It 'animated' life. It was impossible to see how mere atoms and molecules could account for the intricacy and elegance, the fitting of form to function, of a living thing. The world's religions were invoked: G.o.d or the G.o.ds breathed life, soul-stuff, into inanimate matter. The eighteenth-century chemist Joseph Priestley tried to find the 'vital force'. He weighed a mouse just before and just after it died. It weighed the same. All such attempts have failed. If there is soul-stuff, evidently it weighs nothing, that is, it is not made of matter.

Nevertheless, even biological materialists entertained reservations; perhaps, if not plant, animal, fungal and microbial souls, some still undiscovered principle of science was needed to understand life. For example, the British physiologist J.S. Haldane (father of J.B.S. Haldane) asked in 1932: What intelligible account can the mechanistic theory of life give of the ... recovery from disease and injuries? Simply none at all, except that these phenomena are so complex and strange that as yet we cannot understand them. It is exactly the same with the closely related phenomena of reproduction. We cannot by any stretch of the imagination conceive a delicate and complex mechanism which is capable, like a living organism, of reproducing itself indefinitely often.

But only a few decades later and our knowledge of immunology and molecular biology have enormously clarified these once impenetrable mysteries.

I remember very well when the molecular structure of DNA and the nature of the genetic code were first elucidated in the 1950s and 1960s, how biologists who studied whole organisms accused the new proponents of molecular biology of reductionism. (They'll never understand even a worm with their DNA.') Of course reducing everything to a 'vital force' is no less reductionism. But it is now clear that all life on Earth, every single living thing, has its genetic information encoded in its nucleic acids and employs fundamentally the same codebook to implement the hereditary instructions. We have learned how to read the code. The same few dozen organic molecules are used over and over again in biology for the widest variety of functions. Genes bearing significant responsibility for cystic fibrosis and breast cancer have been identified. The 1.8 million rungs of the DNA ladder of the bacterium Haemophilis influenzas, Haemophilis influenzas, comprising its 1,743 genes, have been sequenced. The specific function of most of these genes is beautifully detailed - from the manufacture and folding of hundreds of complex molecules, to protection against heat and antibiotics, to increasing the mutation rate, to making identical copies of the bacterium. Much of the genomes of many other organisms (including the roundworm comprising its 1,743 genes, have been sequenced. The specific function of most of these genes is beautifully detailed - from the manufacture and folding of hundreds of complex molecules, to protection against heat and antibiotics, to increasing the mutation rate, to making identical copies of the bacterium. Much of the genomes of many other organisms (including the roundworm Caenorhabditis elegans) Caenorhabditis elegans) have now been mapped. Molecular biologists are busily recording the sequence of the three billion nucleotides that specify how to make a human being. In another decade or two, they'll be done. (Whether the benefits will ultimately exceed the risks seems by no means certain.) have now been mapped. Molecular biologists are busily recording the sequence of the three billion nucleotides that specify how to make a human being. In another decade or two, they'll be done. (Whether the benefits will ultimately exceed the risks seems by no means certain.) The continuity between atomic physics, molecular chemistry, and that holy of holies, the nature of reproduction and heredity, has now been established. No new principle of science need be invoked. It looks as if there are are a small number of simple facts that can be used to understand the enormous intricacy and variety of living things. (Molecular genetics also teaches that each organism has its own particularity.) a small number of simple facts that can be used to understand the enormous intricacy and variety of living things. (Molecular genetics also teaches that each organism has its own particularity.) Reductionism is even better established in physics and chemistry. I will later describe the unexpected coalescence of our understanding of electricity, magnetism, light and relativity into a single framework. We've known for centuries that a handful of comparatively simple laws not only explains but quant.i.tatively and accurately predicts a breathtaking variety of phenomena, not just on Earth but through the entire Universe.

We hear - for example from the theologian Langdon Gilkey in his Nature, Reality and the Sacred - Nature, Reality and the Sacred - that the notion of the laws of Nature being everywhere the same is simply a preconception imposed on the Universe by fallible scientists and their social milieu. He longs for other kinds of 'knowledge', as valid in their contexts as science is in its. But the order of the Universe is not an a.s.sumption; it's an observed fact. We detect the light from distant quasars only because the laws of electromagnetism are the same ten billion light years away as here. The spectra of those quasars are recognizable only because the same chemical elements are present there as here, and because the same laws of quantum mechanics apply. The motion of galaxies around one another follows familiar Newtonian gravity. Gravitational lenses and binary pulsar spin-downs reveal general relativity in the depths of s.p.a.ce. We that the notion of the laws of Nature being everywhere the same is simply a preconception imposed on the Universe by fallible scientists and their social milieu. He longs for other kinds of 'knowledge', as valid in their contexts as science is in its. But the order of the Universe is not an a.s.sumption; it's an observed fact. We detect the light from distant quasars only because the laws of electromagnetism are the same ten billion light years away as here. The spectra of those quasars are recognizable only because the same chemical elements are present there as here, and because the same laws of quantum mechanics apply. The motion of galaxies around one another follows familiar Newtonian gravity. Gravitational lenses and binary pulsar spin-downs reveal general relativity in the depths of s.p.a.ce. We could could have lived in a Universe with different laws in every province, but we do not. This fact cannot but elicit feelings of reverence and awe. have lived in a Universe with different laws in every province, but we do not. This fact cannot but elicit feelings of reverence and awe.

We might have lived in a Universe in which nothing could be understood by a few simple laws, in which Nature was complex beyond our abilities to understand, in which laws that apply on Earth are invalid on Mars, or in a distant quasar. But the evidence - not the preconceptions, the evidence - proves otherwise. Luckily for us, we live in a Universe in which much can can be 'reduced' to a small number of comparatively simple laws of be 'reduced' to a small number of comparatively simple laws of Nature. Otherwise we might have lacked the intellectual capacity and grasp to comprehend the world.

Of course, we may make mistakes in applying a reductionist programme to science. There may be aspects which, for all we know, are not reducible to a few comparatively simple laws. But in the light of the findings in the last few centuries, it seems foolish to complain about reductionism. It is not a deficiency but one of the chief triumphs of science. And, it seems to me, its findings are perfectly consonant with many religions (although it does not prove prove their validity). Why should a few simple laws of Nature explain so much and hold sway throughout this vast Universe? Isn't this just what you might expect from a Creator of the Universe? Why should some religious people oppose the reductionist programme in science, except out of some misplaced love of mysticism? their validity). Why should a few simple laws of Nature explain so much and hold sway throughout this vast Universe? Isn't this just what you might expect from a Creator of the Universe? Why should some religious people oppose the reductionist programme in science, except out of some misplaced love of mysticism?

Attempts to reconcile religion and science have been on the religious agenda for centuries - at least for those who did not insist on Biblical and Qu'ranic literalism with no room for allegory or metaphor.

The crowning achievements of Roman Catholic theology are the Summa Theologica Summa Theologica and the and the Summa Contra Gentiles Summa Contra Gentiles ('Against the Gentiles') of St Thomas Aquinas. Out of the maelstrom of sophisticated Islamic philosophy that tumbled into Christendom in the twelfth and thirteenth centuries were the books of the ancient Greeks, especially Aristotle, works even on casual inspection of high accomplishment. Was this ancient learning compatible with G.o.d's Holy Word?* In the ('Against the Gentiles') of St Thomas Aquinas. Out of the maelstrom of sophisticated Islamic philosophy that tumbled into Christendom in the twelfth and thirteenth centuries were the books of the ancient Greeks, especially Aristotle, works even on casual inspection of high accomplishment. Was this ancient learning compatible with G.o.d's Holy Word?* In the Summa Theologica, Summa Theologica, Aquinas set himself the task of reconciling 631 questions between Christian and cla.s.sical sources. But how to do this where a clear dispute arises? It cannot be accomplished without some supervening organizing principle, some superior way to know the world. Often, Aquinas appealed to common sense and the natural world, i.e., science used as an error-correcting device. With some contortion of both common sense and Nature, he managed to reconcile all 631 problems. (Although when push came to shove, the desired answer was simply a.s.sumed. Faith always got the nod over Reason.) Similar attempts at reconciliation permeate Talmudic and post-Talmudic Jewish literature and medieval Islamic philosophy. Aquinas set himself the task of reconciling 631 questions between Christian and cla.s.sical sources. But how to do this where a clear dispute arises? It cannot be accomplished without some supervening organizing principle, some superior way to know the world. Often, Aquinas appealed to common sense and the natural world, i.e., science used as an error-correcting device. With some contortion of both common sense and Nature, he managed to reconcile all 631 problems. (Although when push came to shove, the desired answer was simply a.s.sumed. Faith always got the nod over Reason.) Similar attempts at reconciliation permeate Talmudic and post-Talmudic Jewish literature and medieval Islamic philosophy.

[* This was no dilemma for many others. 'I believe; therefore I understand' said St Anselm in the eleventh century.]

But tenets at the heart of religion can be tested scientifically. This in itself makes some religious bureaucrats and believers wary of science. Is the Eucharist, as the Church teaches, in fact and not just as productive metaphor, the flesh of Jesus Christ, or is it, chemically, microscopically and in other ways, just a wafer handed to you by a priest?* Will the world be destroyed at the end of the 52-year Venus cycle unless humans are sacrificed to the G.o.ds?** Does the occasional uncirc.u.mcised Jewish man fare worse than his co-religionists who abide by the ancient covenant in which G.o.d demands a piece of foreskin from every male worshipper? Are there humans populating innumerable other planets, as the Latter Day Saints teach? Were whites created from blacks by a mad scientist, as the Nation of Islam a.s.serts? Would the Sun indeed not rise if the Hindu sacrificial rite is omitted (as we are a.s.sured would be the case in the Satapatha Brahmand)! Satapatha Brahmand)!

[* There was a time when the answer to this question was a matter of life or death. Miles Phillips was an English sailor, stranded in Spanish Mexico. He and his fellows were brought up before the Inquisition in the year 1574. They were asked 'Whether we did not believe that the Host of bread which the priest did hold up over his head, and the wine that was in the chalice, was the very true and perfect body and blood of our Saviour Christ, Yea or No? To which,' Phillips adds, 'if we answered not "Yea!" then there was no way but death.']

[** Since this Mesoamerican ritual has not really been practised for five centuries, we have the perspective to reflect on the tens of thousands of willing and unwilling sacrifices to the Aztec and Mayan G.o.ds who reconciled themselves to their fates with the confident faith that they were dying to save the Universe.]

We can gain some insight into the human roots of prayer by examining those of unfamiliar religions and cultures. Here, for example, is what is written in a cuneiform inscription on a Babylonian cylinder seal from the Second Millennium BC: Oh, Ninlil, Lady of the Lands, in your marriage bed, in the abode of your delight, intercede for me with Enlil, your beloved. [Signed] Mili-Shipak, Shatammu of Ninmah.

It's been a long time since there's been a Shatammu in Ninmah, or even a Ninmah. Despite the fact that Enlil and Ninlil were major G.o.ds - people all over the civilized western world had prayed to them for two thousand years - was poor Mili-Shipak in fact praying to a phantom, to a societally condoned product of his imagination? And if so, what about us? Or is this blasphemy, a forbidden question, as doubtless it was among the worshippers of Enlil?

Does prayer work at all? Which ones?

There's a category of prayer in which G.o.d is begged to intervene in human history or just to right some real or imagined injustice or natural calamity - for example, when a bishop from the American West prays for G.o.d to intervene and end a devastating dry spell. Why is the prayer needed? Didn't G.o.d know of the drought? Was he unaware that it threatened the bishop's parishioners? What is implied here about the limitations of a supposedly omnipotent and omniscient deity? The bishop asked his followers to pray as well. Is G.o.d more likely to intervene when many pray for mercy or justice than when only a few do? Or consider the following request, printed in 1994 in The Prayer and Action Weekly News: Iowa's Weekly Christian Information Source: The Prayer and Action Weekly News: Iowa's Weekly Christian Information Source: Can you join me in praying that G.o.d will burn down the Planned Parenthood in Des Moines in a manner no one can mistake for any human torching, which impartial investigators will have to attribute to miraculous (unexplainable) causes, and which Christians will have to attribute to the Hand of G.o.d?

We've discussed faith-healing. What about longevity through prayer? The Victorian statistician Francis Gallon argued that, other things being equal, British monarchs ought to be very long-lived, because millions of people all over the world daily intoned the heartfelt mantra 'G.o.d Save the Queen' (or King). Yet, he showed, if anything, they don't live as long as other members of the wealthy and pampered aristocratic cla.s.s. Tens of millions of people in concert publicly wished (although they did not exactly pray) that Mao Zedong would live 'for ten thousand years'. Nearly everyone in ancient Egypt exhorted the G.o.ds to let the Pharaoh live 'forever'. These collective prayers failed. Their failure const.i.tutes data.

By making p.r.o.nouncements that are, even if only in principle, testable, religions, however unwillingly, enter the arena of science. Religions can no longer make unchallenged a.s.sertions about reality so long as they do not seize secular power, provided they cannot coerce belief.

This, in turn, has infuriated some followers of some religions. Occasionally they threaten sceptics with the direst imaginable penalties. Consider the following high stakes alternative by William Blake in his innocuously t.i.tled Auguries of Innocence: Auguries of Innocence: He who shall teach the Child to Doubt The rotting Grave shall ne'er get out. The rotting Grave shall ne'er get out. He who respects the Infant's Faith He who respects the Infant's Faith Triumphs over h.e.l.l Death Triumphs over h.e.l.l Death

Of course many religions, devoted to reverence, awe, ethics, ritual, community, family, charity, and political and economic justice, are in no way challenged, but rather uplifted, by the findings of science. There is no necessary conflict between science and religion. On one level, they share similar and consonant roles, and each needs the other. Open and vigorous debate, even the consecration of doubt, is a Christian tradition going back to John Milton's Areopagitica Areopagitica (1644). Some of mainstream Christianity and Judaism embraces and even antic.i.p.ated at least a portion of the humility, self-criticism, reasoned debate, and questioning of received wisdom that the best of science offers. But other sects, sometimes called conservative or fundamentalist - and today they seem to be in the ascendant, with the mainstream religions almost inaudible and invisible - have chosen to make a stand on matters subject to disproof, and thus have something to fear from science. The religious traditions are often so rich and multivariate that they offer ample opportunity for renewal and revision, again especially when their sacred books can be interpreted metaphorically and allegorically. There is thus a middle ground of confessing past errors, as the Roman Catholic Church did in its 1992 acknowledgement that Galileo was right after all, that the Earth does revolve around the Sun: three centuries late, but courageous and most welcome none the less. Modern Roman Catholicism has no quarrel with the Big Bang, with a Universe 15 billion or so years old, with the first living things arising from prebiological molecules, or with humans evolving from ape-like ancestors -although it has special opinions on 'ensoulment'. Most mainstream Protestant and Jewish faiths take the same st.u.r.dy position. (1644). Some of mainstream Christianity and Judaism embraces and even antic.i.p.ated at least a portion of the humility, self-criticism, reasoned debate, and questioning of received wisdom that the best of science offers. But other sects, sometimes called conservative or fundamentalist - and today they seem to be in the ascendant, with the mainstream religions almost inaudible and invisible - have chosen to make a stand on matters subject to disproof, and thus have something to fear from science. The religious traditions are often so rich and multivariate that they offer ample opportunity for renewal and revision, again especially when their sacred books can be interpreted metaphorically and allegorically. There is thus a middle ground of confessing past errors, as the Roman Catholic Church did in its 1992 acknowledgement that Galileo was right after all, that the Earth does revolve around the Sun: three centuries late, but courageous and most welcome none the less. Modern Roman Catholicism has no quarrel with the Big Bang, with a Universe 15 billion or so years old, with the first living things arising from prebiological molecules, or with humans evolving from ape-like ancestors -although it has special opinions on 'ensoulment'. Most mainstream Protestant and Jewish faiths take the same st.u.r.dy position.

In theological discussion with religious leaders, I often ask what their response would be if a central tenet of their faith were disproved by science. When I put this question to the current, Fourteenth, Dalai Lama, he unhesitatingly replied as no conservative or fundamentalist religious leaders do: in such a case, he said, Tibetan Buddhism would have to change.

Even, I asked, if it's a really really central tenet, like (I searched for an example) reincarnation? central tenet, like (I searched for an example) reincarnation?

Even then, he answered.

However, he added with a twinkle, it's going to be hard to disprove reincarnation.

Plainly, the Dalai Lama is right. Religious doctrine that is insulated from disproof has little reason to worry about the advance of science. The grand idea, common to many faiths, of a Creator of the Universe is one such doctrine - difficult alike to demonstrate or to dismiss.

Moses Maimonides, in his Guide for the Perplexed, Guide for the Perplexed, held that G.o.d could be truly known only if there were free and open study of both physics and theology [I, 55]. What would happen if science demonstrated an infinitely old Universe? Then theology would have to be seriously revamped [II, 25]. Indeed, this is the one conceivable finding of science that could disprove a Creator -because an infinitely old universe would never have been created. It would have always been here. held that G.o.d could be truly known only if there were free and open study of both physics and theology [I, 55]. What would happen if science demonstrated an infinitely old Universe? Then theology would have to be seriously revamped [II, 25]. Indeed, this is the one conceivable finding of science that could disprove a Creator -because an infinitely old universe would never have been created. It would have always been here.

There are other doctrines, interests and concerns that also worry about what science will find out. Perhaps, they suggest, it's better not to know. If men and women turn out to have different hereditary propensities, won't this be used as an excuse for the former to suppress the latter? If there's a genetic component of violence, might this justify repression of one ethnic group by another, or even precautionary incarceration? If mental illness is just brain chemistry, doesn't this unravel our efforts to keep a grasp on reality or to be responsible for our actions? If we are not the special handiwork of the Creator of the Universe, if our basic moral laws are merely invented by fallible lawgivers, isn't our struggle to maintain an orderly society undermined?

I suggest that in every one of these cases, religious or secular, we are much better off if we know the best available approximation to the truth, and if we keep before us a keen apprehension of the errors our interest group or belief system has committed in the past. In every case the imagined dire consequences of the truth being generally known are exaggerated. And again, we are not wise enough to know which lies, or even which shadings of the facts, can competently serve some higher social purpose, especially in the long run.

16.

When Scientists Know Sin

The mind of man - how far will it advance? Where will its daring impudence find limits? If human villainy and human life shall wax in due proportion, if the son shall always grow in wickedness past his father, the G.o.ds must add another world to this that all the sinners may have s.p.a.ce enough.

Euripides, Hippolytus Hippolytus (428 BC) (428 BC)

In a post-war meeting with President Harry S Truman, J. Robert Oppenheimer - the scientific director of the Manhattan nuclear weapons project - mournfully commented that scientists had b.l.o.o.d.y hands; they had now known sin. Afterwards, Truman instructed his aides that he never wished to see Oppenheimer again. Sometimes scientists are castigated for doing evil, and sometimes for warning about the evil uses to which science may be put.

More often, science is taken to task because it and its products are said to be morally neutral, ethically ambiguous, as readily employed in the service of evil as of good. This is an old indictment. It goes back probably to the flaking of stone tools and the domestication of fire. Since technology has been with our ancestral line from before the first human, since we are a technological species, this problem is not so much one of science as of human nature. By this I don't mean that science has no responsibility for the misuse of its findings. It has profound responsibility, and the more powerful its products the greater its responsibility.

Like a.s.sault weapons and market derivatives, the technologies that allow us to alter the global environment that sustains us should mandate caution and prudence. Yes, it's the same old humans who have made it so far. Yes, we're developing new technologies as we always have. But when the weaknesses we've always had join forces with a capacity to do harm on an unprecedented planetary scale, something more is required of us - an emerging ethic that also must be established on an unprecedented planetary scale.

Sometimes scientists try to have it both ways: to take credit for those applications of science that enrich our lives, but to distance themselves from the instruments of death, intentional and inadvertent, that also trace back to scientific research. The Australian philosopher John Pa.s.smore writes in his book Science and Its Critics: Science and Its Critics: The Spanish Inquisition sought to avoid direct responsibility for the burning of heretics by handing them over to the secular arm; to burn them itself, it piously explained, would be wholly inconsistent with its Christian principles. Few of us would allow the Inquisition thus easily to wipe its hands clean of bloodshed; it knew quite well what would happen. Equally, where the technological application of scientific discoveries is clear and obvious - as when a scientist works on nerve gases - he cannot properly claim that such applications are 'none of his business', merely on the grounds that it is the military forces, not scientists, who use the gases to disable or kill. This is even more obvious when the scientist deliberately offers help to governments, in exchange for funds. If a scientist, or a philosopher, accepts funds from some such body as an office of naval research, then he is cheating if he knows his work will be useless to them and must take some responsibility for the outcome if he knows that it will be useful. He is subject, properly subject, to praise or blame in relation to any innovations which flow from his work.

An important case history is provided by the career of the Hungarian-born physicist Edward Teller. Teller was marked at a young age by the Bela Kuhn communist revolution in Hungary, in which the property of middle-cla.s.s families like his was expropriated, and by losing part of his leg in a streetcar accident, leaving him in permanent pain. His early contributions ranged from quantum mechanical selection rules and solid state physics to cosmology. It was he who chauffeured the physicist Leo Szilard to the vacationing Albert Einstein on Long Island in July 1939 - a meeting that led to the historic letter from Einstein to President Franklin Roosevelt urging, in view of both scientific and political events in n.a.z.i Germany, that the United States develop a fission, or 'atomic' bomb. Recruited to work on the Manhattan Project, Teller arrived at Los Alamos and promptly refused to cooperate -not because he was dismayed at what an atomic bomb might do, but just the opposite: because he wanted to work on a much more destructive weapon, the fusion, or thermonuclear, or hydrogen bomb. (While there is a practical upper limit on the yield or destructive energy of an atomic bomb, there is no such limit for a hydrogen bomb. But a hydrogen bomb needs an atomic bomb as trigger.) After the fission bomb was invented, after Germany and j.a.pan surrendered, after the war was over, Teller remained a persistent advocate of what was called 'the Super', specifically intended to intimidate the Soviet Union. Concern about the rebuilding, toughened and militarized Soviet Union under Stalin and the national paranoia in America called McCarthyism, eased Teller's path. A substantial obstacle was offered, though, in the person of Oppenheimer, who had become the chairman of the General Advisory Committee to the post-war Atomic Energy Commission. Teller provided critical testimony at a government hearing, questioning Oppenheimer's loyalty to the United States. Teller's involvement is generally thought to have played a major role in the aftermath: although Oppenheimer's loyalty was not exactly impugned by the review board, somehow his security clearance was denied, he was retired from the AEC, and Teller's way to the Super was greased.

The technique for making a thermonuclear weapon is generally attributed to Teller and the mathematician Stanislas Ulam. Hans Bethe, the n.o.bel laureate physicist who headed the Theoretical Division at the Manhattan Project and who played a major role in the development of both the atomic and the hydrogen bombs, attests that Teller's original suggestion was flawed, and that the work of many people was necessary to bring the thermonuclear weapon to reality. With fundamental technical contributions from a young physicist named Richard Garwin, the first US thermonuclear 'device' was exploded in 1952. It was too unwieldy to be carried by a missile or bomber; it just sat there where it was a.s.sembled and blew up. The first true hydrogen bomb was a Soviet invention exploded one year later. There has been debate on whether the Soviet Union would have developed a thermonuclear weapon if the United States had not, and whether a US thermonuclear weapon was even needed to deter Soviet use of their hydrogen bomb, since the US by then possessed a substantial a.r.s.enal of fission weapons. The preponderance of current evidence is that the USSR, even before it exploded its first fission bomb, had a workable design for a thermonuclear weapon. It was 'the next logical step'. But Soviet pursuit of fusion weapons was much aided by the knowledge, from espionage, that the Americans were working on them.

From my point of view, the consequences of global nuclear war became much more dangerous with the invention of the hydrogen bomb, because airbursts of thermonuclear weapons are much more capable of burning cities, generating vast amounts of smoke, cooling and darkening the Earth, and inducing global-scale nuclear winter. This was perhaps the most controversial scientific debate I've been involved in (from about 1983-90). Much of the debate was politically driven. The strategic implications of nuclear winter were disquieting to those wedded to a policy of ma.s.sive retaliation to deter a nuclear attack, or to those wishing to preserve the option of a ma.s.sive first strike. In either case, the environmental consequences work the self-destruction of any nation launching large numbers of thermonuclear weapons even with no retaliation from the adversary. A major segment of the strategic policy of decades, and the reason for acc.u.mulating tens of thousands of nuclear weapons, suddenly became much less credible.

The global temperature declines predicted in the original (1983) nuclear winter scientific paper were 15-20C; current estimates are 10-15C. The two values are in good agreement considering the irreducible uncertainties in the calculations. Both temperature declines are much greater than the difference between current global temperatures and those of the last Ice Age. The long-term consequences of global thermonuclear war have been estimated by an international team of 200 scientists, who concluded that through nuclear winter the global civilization and most of the people on Earth, including those far from the northern mid-lat.i.tude target zone, would be at risk, mainly from starvation. If large-scale nuclear war ever occurs, with cities targeted, the effort of Edward Teller and his colleagues in the United States (and the counterpart team headed by Andrei Sakharov in the Soviet Union) might be responsible for lowering the curtain on the human future. The hydrogen bomb is by far the most horrific weapon ever invented.

When nuclear winter was discovered in 1983, Teller was quick to argue both (1) that the physics was mistaken, and (2) that the discovery had been made years earlier under his tutelage at the Lawrence Livermore National Laboratory. There is in fact no evidence for such a prior discovery, and considerable evidence that those in every nation charged to inform their national leaders of the effects of nuclear weapons had consistently overlooked nuclear winter. But if Teller is right, then it was unconscionable of him not to have disclosed the purported discovery to the affected parties - the citizens and leaders of his nation and the world. As in the Stanley Kubrick movie Dr Strangelove, Dr Strangelove, cla.s.sifying the ultimate weapon - so no one knows that it exists or what it can do - is the ultimate absurdity. cla.s.sifying the ultimate weapon - so no one knows that it exists or what it can do - is the ultimate absurdity.

It seems to me impossible for any normal human being to be untroubled by helping to make such an invention, even putting nuclear winter aside. The stresses, conscious or unconscious, on those who take credit for the contrivance must be considerable. Whatever his actual contributions, Edward Teller has been widely described as the 'father' of the hydrogen bomb. In an admiring 1954 article, Life Life magazine described his 'almost fanatic determination' to build the hydrogen bomb. Much of his subsequent career can, I think, be understood as an attempt to justify what he begat. Teller has contended, not implausibly, that hydrogen bombs keep the peace, or at least prevent thermonuclear war, because the consequences of warfare between nuclear powers are now too dangerous. We haven't had a nuclear war yet, have we? But all such arguments a.s.sume that the nuclear-armed nations are and always will be, without exception, rational actors, and that bouts of anger and revenge and madness will never overtake their leaders (or military and secret police officers in charge of nuclear weapons). In the century of Hitler and Stalin, this seems ingenuous. magazine described his 'almost fanatic determination' to build the hydrogen bomb. Much of his subsequent career can, I think, be understood as an attempt to justify what he begat. Teller has contended, not implausibly, that hydrogen bombs keep the peace, or at least prevent thermonuclear war, because the consequences of warfare between nuclear powers are now too dangerous. We haven't had a nuclear war yet, have we? But all such arguments a.s.sume that the nuclear-armed nations are and always will be, without exception, rational actors, and that bouts of anger and revenge and madness will never overtake their leaders (or military and secret police officers in charge of nuclear weapons). In the century of Hitler and Stalin, this seems ingenuous.

Teller has been a major force in preventing a comprehensive treaty banning nuclear weapons tests. He made it much more difficult to accomplish the 1963 Limited (above-ground) Test Ban Treaty. His argument that above-ground testing was essential to maintain and 'improve' the nuclear a.r.s.enals, that ratifying the treaty would 'give away the future safety of our country' has proven specious. He has also been a vigorous proponent of the safety and cost-effectiveness of fission power plants, claiming himself to be the only casualty of the Three Mile Island nuclear accident in Pennsylvania in 1979; he had a heart attack, he says, debating the issue.

Teller advocated exploding nuclear weapons from Alaska to South Africa, to dredge harbours and ca.n.a.ls, to obliterate troublesome mountains, to do heavy earth-moving. When he proposed such a scheme to Queen Frederika of Greece, she is said to have responded, 'Thank you, Dr Teller, but Greece has enough quaint ruins already.' Want to test Einstein's general relativity? Then explode a nuclear weapon on the far side of the Sun, Teller proposed. Want to understand the chemical composition of the Moon? Then fly a hydrogen bomb to the Moon, explode it, and examine the spectrum of the flash and fireball.

Also in the 1980s, Teller sold President Ronald Reagan the notion of Star Wars, called by them the 'Strategic Defense Initiative', SDI. Reagan seems to have believed a highly imaginative story of Teller's that it was possible to build a desk-sized orbiting hydrogen-bomb-driven X-ray laser that would destroy 10,000 Soviet warheads in flight, and provide genuine protection for the citizens of the United States in case of global thermonuclear war.

It is claimed by apologists for the Reagan administration that, whatever the exaggerations in capability, some of it intentional, SDI was responsible for the collapse of the Soviet Union. There is no serious evidence in support of this contention. Andrei Sakharov, Yevgeny Velikhov, Roald Sagdeev, and other scientists who advised President Mikhail Gorbachev made it clear that if the United States really went ahead with a Star Wars programme, the safest and cheapest Soviet response would be merely to augment its existing a.r.s.enal of nuclear weapons and delivery systems. In this way Star Wars could have increased, not decreased, the peril of thermonuclear war. At any rate, Soviet expenditures on s.p.a.ce-based defences against American nuclear missiles were comparatively paltry, hardly of a magnitude to trigger a collapse of the Soviet economy. The fall of the USSR has much more to do with the failure of the command economy, growing awareness of the standard of living in the west, widespread disaffection from a moribund Communist ideology, and - although he did not intend such an outcome - Gorbachev's promotion of glasnost, glasnost, or openness. or openness.

Ten thousand American scientists and engineers publicly pledged they would not work on Star Wars or accept money from the SDI organization. This provides an example of widespread and courageous non-cooperation by scientists (at some conceivable personal cost) with a democratic government that had, temporarily at least, lost its way.

Teller has also advocated the development of burrowing nuclear warheads, so that underground command centres and deeply buried shelters for the leadership (and their families) of an adversary nation might be dug down to and wiped out; and 0.1-kiloton nuclear warheads that would saturate an enemy country, obliterating its infrastructure 'without a single casualty'. Civilians would be alerted in advance. Nuclear war would be humane.

As I write, Edward Teller - still vigorous and retaining considerable intellectual powers into his late eighties - has mounted a campaign, with his counterpart in the former Soviet nuclear weapons establishment, to develop and explode new generations of high-yield thermonuclear weapons in s.p.a.ce, in order to destroy or deflect asteroids that might be on collision trajectories with the Earth. I worry that premature experimentation with the orbits of nearby asteroids may involve extreme dangers for our species.

Dr Teller and I have met privately. We've debated at scientific meetings, in the national media, and in a closed rump session of Congress. We've had strong disagreements, especially on Star Wars, nuclear winter and asteroid defence. Perhaps all this has hopelessly coloured my view of him. Although he has always been a fervent anticommunist and technophile, as I look back over his life it seems to me I see something more in his desperate attempt to justify the hydrogen bomb: its effects aren't as bad as you might think. It can be used to defend the world from other hydrogen bombs, for science, for civil engineering, to protect the population of the United States against an enemy's thermonuclear weapons, to wage war humanely, to save the planet from random hazards from s.p.a.ce. Somehow, somewhere, he wants to believe that thermonuclear weapons, and he, will be acknowledged by the human species as its saviour and not its destroyer.

When scientific research provides fallible nations and political leaders with formidable, indeed awesome powers, many dangers present themselves: one is that some of the scientists involved may lose all but a superficial semblance of objectivity. As always, power tends to corrupt. In this circ.u.mstance, the inst.i.tution of secrecy is especially pernicious, and the checks and balances of a democracy become especially valuable. (Teller, who has flourished in the secrecy culture, has also repeatedly attacked it.) The CIA Inspector General commented in 1995 that 'absolute secrecy corrupts absolutely'. The most open and vigorous debate is often the only protection against the most perilous misuse of technology. The critical piece of the counterargument may be something obvious that many scientists or even lay people could come up with provided there were no penalties for speaking out. Or it might be something more subtle, something that would be noted by an obscure graduate student in some locale remote from Washington, DC, who, if the arguments were closely held and highly secret, would never have the opportunity to address the issue.

What realm of human endeavour is not morally ambiguous? Even folk inst.i.tutions that purport to give us advice on behaviour and ethics seem fraught with contradictions. Consider aphorisms -haste makes waste; yes, but a st.i.tch in time saves nine. Better safe than sorry; but nothing ventured, nothing gained. Where there's smoke, there's fire; but you can't tell a book by its cover. A penny saved is a penny earned; but you can't take it with you. He who hesitates is lost; but fools rush in where angels fear to tread. Two heads are better than one; but too many cooks spoil the broth. There was a time when people planned or justified their actions on the basis of such contradictory plat.i.tudes. What is the moral responsibility of the aphorist? Or the Sun-sign astrologer, the Tarot card reader, the tabloid prophet?

Or consider the mainstream religions. We are enjoined in Micah Micah to do justly and love mercy; in to do justly and love mercy; in Exodus Exodus we are forbidden to commit murder; in we are forbidden to commit murder; in Leviticus Leviticus we are commanded to love our neighbour as ourselves; and in we are commanded to love our neighbour as ourselves; and in the Gospels the Gospels we are urged to love our enemies. Yet think of the rivers of blood spilled by fervent followers of the books in which these well-meaning exhortations are embedded. we are urged to love our enemies. Yet think of the rivers of blood spilled by fervent followers of the books in which these well-meaning exhortations are embedded.

In Joshua Joshua and in the second half of and in the second half of Numbers Numbers is celebrated the ma.s.s murder of men, women, children, down to the domestic animals in city after city across the whole land of Canaan. Jericho is obliterated in a is celebrated the ma.s.s murder of men, women, children, down to the domestic animals in city after city across the whole land of Canaan. Jericho is obliterated in a kherem, kherem, a 'holy war'. The only justification offered for this slaughter is the ma.s.s murderers' claim that, in exchange for circ.u.mcising their sons and adopting a particular set of rituals, their ancestors were long before promised that this land was their land. Not a hint of self-reproach, not a muttering of patriarchal or divine disquiet at these campaigns of extermination can be dug out of holy scripture. Instead, Joshua 'destroyed all that breathed, as the Lord G.o.d of Israel commanded' (Joshua, x, 40). And these events are not incidental, but central to the main narrative thrust of the Old Testament. Similar stories of ma.s.s murder (and in the case of the Amalekites, genocide) can be found in the books of a 'holy war'. The only justification offered for this slaughter is the ma.s.s murderers' claim that, in exchange for circ.u.mcising their sons and adopting a particular set of rituals, their ancestors were long before promised that this land was their land. Not a hint of self-reproach, not a muttering of patriarchal or divine disquiet at these campaigns of extermination can be dug out of holy scripture. Instead, Joshua 'destroyed all that breathed, as the Lord G.o.d of Israel commanded' (Joshua, x, 40). And these events are not incidental, but central to the main narrative thrust of the Old Testament. Similar stories of ma.s.s murder (and in the case of the Amalekites, genocide) can be found in the books of Saul, Esther, Saul, Esther, and elsewhere in the Bible, with hardly a pang of moral doubt. It was all, of course, troubling to liberal theologians of a later age. and elsewhere in the Bible, with hardly a pang of moral doubt. It was all, of course, troubling to liberal theologians of a later age.

It is properly said that the Devil can 'quote Scripture to his purpose'. The Bible is full of so many stories of contradictory moral purpose that every generation can find scriptural justification for nearly any action it proposes, from incest, slavery and ma.s.s murder to the most refined love, courage and self-sacrifice. And this moral multiple personality disorder is hardly restricted to Judaism and Christianity. You can find it deep within Islam, the Hindu tradition, indeed nearly all the world's religions. Perhaps then it is not so much scientists as people who are morally ambiguous.

It is the particular task of scientists, I believe, to alert the public to possible dangers, especially those emanating from science or foreseeable through the use of science. Such a mission is, you might say, prophetic. Clearly the warnings need to be judicious and not more flamboyant than the dangers require; but if we must make errors, given the stakes, they should be on the side of safety.

Among the IKung San hunter-gatherers of the Kalahari Desert, when two men, perhaps testosterone-inflamed, would begin to argue, the women would reach for their poison arrows and put the weapons out of harm's way. Today our poison arrows can destroy the global civilization and just possibly annihilate our species. The price of moral ambiguity is now too high. For this reason - and not because of its approach to knowledge - the ethical responsibility of scientists must also be high, extraordinarily high, unprecedent-edly high. I wish graduate science programmes explicitly and systematically raised these questions with fledgling scientists and engineers. And sometimes I wonder whether in our society, too, the women - and the children - will eventually put the poison arrows out of harm's way.