That was a false start. More recently, the Soviet scientists, who had been following two radically dissimilar lines, discovered one that was promising, maybe more than promising. It has been christened by the acronym 'tokamak'. The Americans, who were following a similar path, took up tokamak with vigour, using, as a pleasant cordiality, the same nickname. There had been signs, still being argued about, of a step forward. The tokamak is a ring-shaped tube, like a hollow doughnut. Magnetic fields keep the super-hot hydrogen at the central axis of the tube, so that it cannot touch the metal walls and burn its way out. Another, completely different, approach to fusion power is to package the hydrogen into small pellets only a few millimetres across, and blast them from all sides with laser power or beams of electrons.

At present, no outsider could say more about the state of fusion power with meaning, and the insiders, if they can, prefer not to. It may be years before they know for sure, and longer before either society gets to work on practical engineering. The cost, to begin with, will be stupendous but the rewards will be stupendous too.

What the physicists have done, speaks for itself. It would be jejune to add anything. Their own intellectual structure waits there to be added to, but is unshakeable. The application which has come out of that structure has left us with some threats and more promises. It is for the general intelligence of us all to make the best of both.

Appendices.

I: A New Means of Destruction.

Editorial by C P Snow in Discovery, September 1939 Some physicists think that, within a few months, science will have produced for military use an explosive a million times more violent than dynamite. It is no secret; laboratories in the United States, Germany, France and England have been working on it feverishly since the Spring. It may not come off. The most competent opinion is divided upon whether the idea is practicable. If it is, science for the first time will at one bound have altered the scope of warfare. The power of most scientific weapons has been consistently exaggerated; but it would be difficult to exaggerate this.

So there are two questions. Will it come off? How will the world be affected if it does?

As to the practicability, most of our opinions are worth little. The most eminent physicist with whom I have discussed it thinks it improbable; I have talked to others who think it as good as done. In America, as soon as the possibility came to light, it seemed so urgent that a representative of American physicists telephoned the White House and arranged an interview with the President. That was about three months ago. And it is in America where the thing will in all probability be done, if it is done at all.

The principle is fairly simple, and is discussed by Mr D W F Mayer in more detail on p. 459. Briefly, it is this: a slow neutron knocks a uranium nucleus into two approximately equal pieces, and two or more faster neutrons are discharged at the same time. These faster neutrons go on to disintegrate other uranium nuclei, and the process is self-accelerating. It is the old dream of the release of intra-atomic energy, suddenly made actual at a time when most scientists had long discarded it; energy is gained by the trigger action of the first neutrons.

The idea of the uranium bomb is to disintegrate in this manner an entire lump of uranium. As I have said, many physicists of sound judgement consider that the technical difficulties have already been removed; but their critics ask if this scheme were really workable, why have not the great uranium mines (the biggest are in Canada and the Congo) blown themselves up long ago? The percentage of uranium in pitchblende is very high: and there are always enough neutrons about to set such a trigger action going.

Well, in such a scientific controversy, with some of the ablest physicists in the world on each side, it would be presumptuous to intrude. But on the result there may depend a good many lives, and perhaps more than that.

For what will happen, if a new means of destruction, far more effective than any now existing, comes into our hands? I think most of us, certainly those working day and night this summer upon the problem in New York, are pessimistic about the result. We have seen too much of human selfishness and frailty to pretend that men can be trusted with a new weapon of gigantic power. Most scientists are by temperament fairly hopeful and simple-minded about political things: but in the last eight years that hope has been drained away. In our time, at least, life has been impoverished, and not enriched, by the invention of flight. We cannot delude ourselves that this new invention will be better used.

Yet it must be made, if it really is a physical possibility. If it is not made in America this year, it may be next year in Germany. There is no ethical problem; if the invention is not prevented by physical laws, it will certainly be carried out somewhere in the world. It is better, at any rate, that America should have six months' start.

But again, we must not pretend. Such an invention will never be kept secret; the physical principles are too obvious, and within a year every big laboratory on earth would have come to the same result. For a short time, perhaps, the U S Government may have this power entrusted to it; but soon after it will be in less civilized hands.

THE EDITOR.

II: Einstein's Letter to President Roosevelt.

Albert Einstein.

Old Grove Rd.

Na.s.sau Point Peconic, Long Island August 2nd, 1939.

F D Roosevelt, President of the United States, White House Washington, DC.

Sir:.

Some recent work by E Fermi and L Szilard, which has been communicated to me in ma.n.u.script, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration. I believe therefore that it is my duty to bring to your attention the following facts and recommendations: In the course of the last four months it has been made probable through the work of Joliot in France as well as Fermi and Szilard in America that it may become possible to set up a nuclear chain reaction in a large ma.s.s of uranium, by which vast amounts of power and large quant.i.ties of new radium-like elements would be generated. Now it appears almost certain that this could be achieved in the immediate future.

This new phenomenon would also lead to the construction of bombs, and it is conceivable though much less certain that extremely powerful bombs of a new type may thus be constructed. A single bomb of this type, carried by boat and exploded in a port, might very well destroy the whole port together with some of the surrounding territory. However, such bombs might very well prove to be too heavy for transportation by air.

The United States has only very poor ores of uranium in moderate quant.i.ties. There is some good ore in Canada and the former Czechoslovakia, while the most important source of uranium is Belgian Congo.

In view of this situation you may think it desirable to have some permanent contact maintained between the Administration and the group of physicists working on chain reactions in America. One possible way of achieving this might be for you to entrust with this task a person who has your confidence and who could perhaps serve in an inofficial capacity. His task might comprise the following: a) to approach Government Departments, keep them informed of the further development, and put forward recommendations for Government action, giving particular attention to the problem of securing a supply of uranium ore for the United States; b) to speed up the experimental work, which is at present being carried on within the limits of the budgets of University laboratories, by providing funds, if such funds be required, through his contacts with private persons who are willing to make contributions for this cause, and perhaps also by obtaining the co-operation of industrial laboratories which have the necessary equipment.

I understand that Germany has actually stopped the sale of uranium from the Czechoslovakian mines which she has taken over. That she should have taken such early action might perhaps be understood on the ground that the son of the German Under-Secretary of State, von Weizscker, is attached to the Kaiser-Wilhelm-Inst.i.tut in Berlin where some of the American work on uranium is now being repeated.

Yours very truly, (Albert Einstein).

III: The Moral Un-neutrality of Science.

Speech by C P Snow delivered in 1960 to the American a.s.sociation for the Advancement of Science Scientists are the most important occupational group in the world today. At this moment, what they do is of pa.s.sionate concern to the whole of human society. At this moment, the scientists have little influence on the world effect of what they do. Yet, potentially, they can have great influence. The rest of the world is frightened both of what they do that is, the intellectual discoveries of science and of its effect. The rest of the world, transferring its fears, is frightened of the scientists themselves and tends to think of them as radically different from other men.

As an ex-scientist, if I may call myself so, I know that is nonsense. I have even tried to express in fiction some kinds of scientific temperament and scientific experience. I know well enough that scientists are very much like other men. After all, we're all human, even if some of us don't look it. I think I would be prepared to risk a generalization. The scientists I have known and because of my official life I think I've known as many as anyone in the world have been in certain respects at least as morally admirable as most other groups of intelligent men.

That is a sweeping statement and I mean it only in a statistical sense. But I think there is just a little in it. The moral qualities I admire in scientists are quite simple ones, but I am very suspicious of attempts to over-subtilize moral qualities. It is nearly always a sign, not of true sophistication, but of a specific kind of triviality. So I admire in scientists very simple virtues like courage, truth-telling, kindness in which, judged by the low standards which the rest of us manage to achieve, the scientists are not deficient. I think on the whole the scientists make slightly better husbands and fathers than most of us, and I admire them for it. I don't know the figures, and I should be curious to have them sorted out, but I am prepared to bet that the proportion of divorces among scientists is slightly but significantly less than that among other groups of similar education and income. I do not apologize for considering that a good thing.

A close friend of mine is a very distinguished scientist. He is also one of the few scientists I know who have lived what we used to call a Bohemian life. When we were both younger, he thought he would undertake historical research to see how many great scientists had been as miscellaneously fond of women as he was. I think he would have felt mildly supported if he could have found a precedent. I remember his reporting to me that his researches hadn't had any luck. The really great scientists were depressingly 'normal'. The only gleam of comfort was in the life of Jerome Cardan; and Cardan just wasn't anything like enough to outweigh all the others.

So scientists are not much different from other men. They are certainly no worse than other men. But they do differ from other men in one thing. That is the point I started from. Whether they like it or not, what they do is of critical importance for the human race. Intellectually, it has transformed the climate of our time. Socially, it will decide whether we live or die, and how we live or die. It holds decisive powers for good and evil. That is the situation in which the scientists find themselves. They may not have asked for it, or may only have asked for it in part, but they cannot escape it. They think, many of the more sensitive of them, that they don't deserve to have this weight of responsibility heaved upon them. All they want to do is get on with their work. I sympathize. But the scientists can't escape the responsibility any more than they, or the rest of us, can escape the gravity of the moment in which we stand.

There is, of course, one way to contract out. It has been a favourite way for intellectual persons caught in the midst of water too rough for them.

It consists of the invention of categories or, if you like, of the division of moral labour. That is, the scientists who want to contract out say, we produce the tools. We stop there. It is for you the rest of the world, the politicians to say how the tools are used. The tools may be used for purposes which most of us would regard as bad. If so we are sorry. But as scientists, that is no concern of ours.

This is the doctrine of the ethical neutrality of science. I can't accept it for an instant. I don't believe any scientist of serious feeling can accept it. It is hard, some think, to find the precise statements which will prove it wrong. Yet we nearly all feel intuitively that the invention of comfortable categories is a moral trap. It is one of the easier methods of letting the conscience rust. It is exactly what the early nineteenth-century economists, such as Ricardo, did in the face of the facts of the first industrial revolution. We wonder now how men, intelligent men, can have been so morally blind. We realize how the exposure of that moral blindness gave Marxism its apocalyptic force. We are now, in the middle of the scientific or second industrial revolution, in something like the same position as Ricardo. Are we going to let our consciences rust? Can we ignore that intimation we nearly all have, that scientists have a unique responsibility? Can we believe it, that science is morally neutral?

To me it would be dishonest to pretend otherwise there is only one answer to those questions. Yet I have been brought up in the presence of the same intellectual categories as most Western scientists. It would be dishonest to pretend that I find it easy to construct a rationale which expresses what I now believe. The best I can hope for is to fire a few sighting shots. Perhaps someone who sees more clearly than I can will come along and make a real job of it.

Let me begin by a remark which seems some way off the point. Anyone who has ever worked in science knows how much aesthetic joy he has obtained. That is, in the actual activity of science, in the process of making a discovery, however humble it is, one can't help feeling an awareness of beauty. The subjective experience, the aesthetic satisfaction, seems exactly the same as the satisfaction one gets from writing a poem or a novel, or composing a piece of music. I don't think anyone has succeeded in distinguishing between them. The literature of scientific discovery is full of this aesthetic joy. The very best communication of it that I know comes in G H Hardy's book A Mathematician's Apology. Graham Greene once said he thought that, along with Henry James' prefaces, this was the best account of the artistic experience ever written. But one meets the same thing throughout the history of science. Bolyai's great yell of triumph when he saw he could construct a self-consistent non-Euclidian geometry: Rutherford's revelation to his colleagues that he knew what the atom was like: Darwin's slow, patient, timorous certainty that at last he had got there all these are voices, different voices, of aesthetic ecstasy.

That is not the end of it. The result of the activity of science, the actual finished piece of scientific work, has an aesthetic value in itself. The judgements pa.s.sed on it by other scientists will, more often than not, be expressed in aesthetic terms: 'That's beautiful,' or 'That really is very pretty!' (as the understating English tend to say). The aesthetics of scientific constructs, like the aesthetics of works of art, are variegated. We think some of the great syntheses, like Newton's, beautiful because of their cla.s.sical simplicity, but we see a different kind of beauty in the relativistic extension of the wave equation, or the interpretation of the structure of dioxyribonucleic acid, perhaps because of the touch of unexpectedness. But scientists know their kinds of beauty when they see them. They are suspicious, and scientific history shows they have always been right to be so, when a subject is in an 'ugly' state. For example, most physicists feel in their bones that the present bizarre a.s.sembly of nuclear particles, as grotesque as a stamp collection, can't possibly be, in the long run, the last word.

We should not restrict the aesthetic values to what we call 'pure' science. Applied science has its beauties, which are, in my view, identical in nature. The magnetron has been a marvellously useful device, yet it was a beautiful device, not exactly apart from its utility, but because it did, with such supreme economy, precisely what it was designed to do. Right down in the field of development, the aesthetic experience is just as real to engineers. When they forget it, when they begin to design heavy power equipment about twice as heavy as it needs to be, engineers are the first to know that they are lacking virtue.

There is no doubt, then, about the aesthetic content of science, both in the activity and the result. But aesthetics has no connection with morals, say the categorizers. I don't want to waste time on peripheral issues but are you quite sure of that? Or is it possible that these categories are inventions to make us evade the human and social conditions in which we now exist? But let's move straight on to something else, which is right in the grain of the activity of science and which is at the same time quintessentially moral. I mean, the desire to find the truth.

By truth I don't intend anything complicated, once again. I am using truth as a scientist uses it. We all know that the philosophical examination of the concept of empirical truth gets us into some curious complexities, but most scientists really don't care. They know that the truth, as they use the word, and as the rest of us use it in the language of human speech, is what makes science work. That is good enough for them. On it rests the whole great edifice of modern science. They have a sneaking sympathy for Rutherford who, when asked to examine the philosophical bases of science, was inclined to reply, as he did to the metaphysician, Samuel Alexander: 'Well, what have you been talking all your life, Alexander? Just hot air! Nothing but hot air!'

Anyway, truth in their own straightforward sense is what scientists are trying to find. They want to find what is there. Without that desire, there is no science. It is the driving-force of the whole activity. It compels the scientist to have an overriding respect for truth, every stretch of the way. That is, if you're going to find what is there, you must not deceive yourself or anyone else. You mustn't lie to yourself. At the crudest level, you mustn't fake your experiments.

Curiously enough, scientists do try to behave like that. A short time ago I wrote a novel where the story hinged on a case of scientific fraud. But I made one of my characters, who was himself a very good scientist, say that, considering the opportunities and temptations, it is astonishing how few such cases there are. We have all heard of perhaps half a dozen open and notorious ones, which are on the record for anyone to read ranging from the 'discovery' of L-radiation to the singular episode of the Piltdown man.

We have all, if we have lived any time in the scientific world, heard private talk of something like another dozen cases which for various reasons are not yet public property. In some of those cases, we know the motives for cheating sometimes, but not always, sheer personal advantage, such as getting money or a job. But not always. A special kind of vanity has led more than one man into scientific faking. At a lower level of research, there are presumably some more cases. There must have been occasional PhD students who sc.r.a.ped by with the help of a bit of fraud.

But the total number of all these men is vanishingly small by the side of the total number of scientists. Incidentally, the effect on science of such frauds is also vanishingly small. Science is a self-correcting system. That is, no fraud (or honest mistake) is going to stay undetected for long. There is no need for an extrinsic scientific criticism, because criticism is inherent in the process itself. So that all that a fraud can do is waste the time of the scientists who have to clear it up.

The remarkable thing is not the handful of scientists who deviate from the search for truth but the overwhelming numbers who keep to it. That is a demonstration, absolutely clear for anyone to see, of moral behaviour on a very large scale.

We take it for granted. Yet it is very important. It differentiates science in its widest sense (which includes scholarship) from all other intellectual activities. There is a built-in moral component right in the core of the scientific activity itself. The desire to find the truth is itself a moral impulse, or at least contains a moral impulse. The way in which a scientist tries to find the truth imposes on him a constant moral discipline. We say a scientific conclusion such as the contradiction of parity by Lee and Yang is 'true' in the limited sense of scientific truth, just as we say that it is 'beautiful' according to the criteria of scientific aesthetics. We also know that to reach this conclusion took a set of actions which would have been useless without the moral motive. That is, all through the experiments of Wu and her colleagues, there was the constant moral exercise of seeking and telling the truth. To scientists, who are brought up in this climate, this seems as natural as breathing. Yet it is a wonderful thing. Even if the scientific activity contained only this one moral component, that would be enough to let us say that it was morally un-neutral.

But is this the only moral component? All scientists would agree about the beauty and the truth. In the Western world, they wouldn't agree on much more. Some will feel with me in what I'm going to say. Some will not. That doesn't affect me much, except that I am worried by the growth of an att.i.tude I think very dangerous, a kind of technological conformity disguised as cynicism. I shall say a little more about that later. As for disagreement, G H Hardy used to comment that a serious man never ought to waste his time stating a majority opinion there are plenty of others to do that. That was the voice of cla.s.sical scientific non-conformity. I wish that we heard it more often.

Let me cite some grounds for hope. Any of us who were doing science before 1933 can remember what the atmosphere was like. It is a terrible bore when ageing men speak about the charms of their youth. Yet I'm going to irritate you just as Talleyrand irritated his juniors by saying that unless one was on the scene before 1933, one hasn't known the sweetness of the scientific life. The scientific world of the Twenties was as near a full-fledged international community as we're likely to get. Don't think I'm saying that the men involved were superhuman or free from the ordinary frailties. That wouldn't come well from me, who've spent a fraction of my writing-life pointing out that scientists are, first and foremost, men. But the atmosphere of the Twenties in science was filled with an air of benevolence and magnanimity which transcended the people who lived in it.

Anyone who ever spent a week in Cambridge or Gttingen or Copenhagen felt it all round him. Rutherford had many human faults, but he was a great man with abounding human generosity. For him the world of science was a world that lived on a plane above the nation-state, and lived there with joy. That was at least as true of those two other great men, Niels Bohr and Franck, and some of that spirit rubbed off on to the pupils round them. The same was true of the Roman school of physics.

The personal links within this international world were very close. It is worth remembering that Peter Kapitsa, who was a loyal Soviet citizen, honoured my country by working in Rutherford's laboratory for many years. He became a Fellow of the Royal Society, a Fellow of Trinity College, Cambridge, and the founder and king pin of the best physics club Cambridge has known. He never gave up his Soviet citizenship and is now Director of the Inst.i.tute of Physical Problems in Moscow. Through him a generation of English scientists came to have personal knowledge of Russian scientists. These exchanges were then, and have remained, more valuable than all the diplomatic exchanges ever invented.

The Kapitsa phenomenon couldn't take place now. I hope to live to see the day when a young Kapitsa can once more work for sixteen years in Berkeley or Cambridge and then go back to an eminent place in his own country. When that can happen, we are all right. But after the idyllic years of world science we pa.s.sed into a tempest of history: and, I suppose by an unfortunate coincidence, we pa.s.sed into a technological tempest too.

The discovery of atomic fission broke up the world of international physics. 'This has killed a beautiful subject,' said Mark Oliphant, the father-figure of Australian physics, in 1945, after the bombs had dropped. In intellectual terms, he has not turned out right. But in spiritual or moral terms, I sometimes think he has.

A good deal of the international community of science remains in other fields in great areas of biology, for example. Many biologists are feeling the identical liberation, the identical joy at taking part in a magnanimous enterprise, that physicists felt in the Twenties. It is more than likely that the moral and intellectual leadership of science will pa.s.s to the biologists, and it is among them that we shall find the Einsteins, Rutherfords and Bohrs of the next generation.

Physicists have had a bitterer task. With the discovery of fission, and with some technical breakthroughs in electronics, physicists became, almost overnight, the most important military resource a nation-state could call on. A large number of physicists became soldiers-not-in-uniform. So they have remained, in the advanced societies, ever since.

It is very difficult to see what else they could have done. All this began in the Hitler war. Most scientists thought then that n.a.z.ism was as near absolute evil as a human society can manage. I myself think so, without qualification. That being so, n.a.z.ism had to be fought, and since the n.a.z.is might make fission bombs which we thought possible until 1944 and which was a constant nightmare if one was remotely in the know well, then, we had to make them too. Unless one was an unlimited pacifist, there was nothing else to do. And unlimited pacifism is a position which most of us cannot sustain.

Therefore I respect, and to a large extent share, the moral att.i.tudes of those scientists who devoted themselves to making the bomb. But the trouble is, when you get on to any kind of moral escalator, to know whether you're ever going to be able to get off. When scientists become soldiers, they give up something, so imperceptibly that they don't realize it, of the full scientific life. Not intellectually. I see no evidence that scientific work on weapons of maximum destruction has been in any intellectual respect different from other scientific work. But there is a moral difference.

It may be and scientists who are better men than I am often take this att.i.tude, and I have tried to represent it faithfully in one of my books that this is a moral price which, in certain circ.u.mstances, has to be paid. Nevertheless, it is no good pretending that there is not a moral price. Soldiers have to obey. That is the foundation of their morality. It is not the foundation of the scientific morality. Scientists have to question, and if necessary to rebel. I don't want to be misunderstood. I am no anarchist. I am not suggesting that loyalty is not a prime virtue. I am not saying that all rebellion is good. But I am saying that loyalty can easily turn into conformity, and that conformity can often be a cloak for the timid and self-seeking. So can obedience, carried to the limit. When you think of the long and gloomy history of man, you will find that far more, and more hideous, crimes have been committed in the name of obedience than have ever been committed in the name of rebellion. If you doubt that, read William Shirer's Rise and Fall of the Third Reich. The German officer corps were brought up in the most rigorous code of obedience. To themselves, no more honourable and G.o.d-fearing body of men could conceivably exist. Yet in the name of obedience they were party to, and a.s.sisted in, the most wicked large-scale actions in the history of the world.

Scientists must not go that way. Yet the duty to question is not much of a support when you're living in the middle of an organized society. I speak with feeling here. I was an official for twenty years. I went into official life at the beginning of the war, for the reasons that prompted my scientific friends to make weapons. I stayed in that life until a year ago, for the same reason that made my scientific friends turn into civilian soldiers. The official's life in England is not quite so disciplined as a soldier's, but it is very nearly so. I think I know the virtues, which are very great, of the men who live that disciplined life. I also know what for me was the moral trap. I, too, had got on to an escalator. I can put the result in a sentence: I was hiding behind the inst.i.tution, I was losing the power to say 'No'.

Only a very bold man, when he is a member of an organized society, can keep the power to say 'No'. I tell you that, not being a very bold man or one who finds it congenial to stand alone, away from his colleagues. We can't expect many scientists to do it. Is there any tougher ground for them to stand on? I suggest to you that there is. I believe that there is a spring of moral action in the scientific activity which is at least as strong as the search for truth. The name of this spring is Knowledge. Scientists know certain things in a fashion more immediate and more certain than those who don't know what science is. Unless we are abnormally weak or abnormally wicked men, this knowledge is bound to shape our actions. Most of us are timid, but to an extent, knowledge gives us guts. Perhaps it can give us guts strong enough for the jobs in hand.

Let me take the most obvious example. All physical scientists know that it is astonishingly easy to make plutonium. We know this, not as a journalistic fact at second hand, but as a fact in our own experience. We can work out the number of scientific and engineering personnel it needs for a nation-state to equip itself with fission and fusion bombs. We know that for a dozen or more states, it would only take perhaps five years, perhaps less. Even the best informed of us always exaggerate these periods.

This we know, with the certainty of what shall I call it engineering truth. We also, most of us, are familiar with statistics and the nature of odds. We know, with the certainty of established truth, that if enough of these weapons are made, by enough different states, some of them are going to blow up through accident, or folly, or madness; but the numbers don't matter, what does matter is the nature of the statistical fact.

All this we know. We know it in a more direct sense than any politician can know it, because it comes from our direct experience. It is part of our minds. Are we going to let it happen?

All this we know. It throws upon scientists a direct and formal responsibility. It is not enough to say scientists have a responsibility as citizens. They have a much greater one than that, and one different in kind. For scientists have a moral imperative to say what they know. It is going to make them unpopular in their own nation-states. It may do worse than make them unpopular. That doesn't matter. Or at least, it does matter to you and me, but it must not count in the face of the risks.

For we genuinely know the risks. We are faced with an either/or and we haven't much time. The either is acceptance of a restriction of nuclear armaments. This is going to begin, just as a token, with an agreement on the stopping of nuclear tests. The United States is not going to get the 99.9 per cent 'security' that it has been asking for. This is un.o.btainable, though there are other bargains that the United States could probably secure. I am not going to conceal from you that this course involves certain risks. They are quite obvious, and no honest man is going to blink them. That is the either. The or is not a risk but a certainty. It is this. There is no agreement on tests. The nuclear arms race between the United States and the USSR not only continues but accelerates. Other countries join in. Within, at the most, six years, China and six other states have a stock of nuclear bombs. Within, at the most, ten years, some of those bombs are going off. I am saying this as responsibly as I can. That is the certainty. On the one side, therefore, we have a finite risk. On the other side, we have a certainty of disaster. Between a wish and a certainty, a sane man does not hesitate.

It is the plain duty of scientists to explain the either/or. It is a duty which seems to me to live in the moral nature of the scientific activity itself.

The same duty, though in a much more pleasant form, arises with respect to the benevolent powers of science. For scientists know, and again with the certainty of scientific knowledge, that we possess every scientific fact we need to transform the physical life of half the world. And transform within the span of people now living. I mean, we have all the resources to help half the world live as long as we do, and eat enough. All that is missing is the will. We know that. Just as we know that you in the United States, and to a slightly less extent, we in the United Kingdom, have been almost unimaginably lucky. We are sitting like people in a smart and cosy restaurant, and we are eating comfortably, looking out of the window into the streets. Down on the pavement are people looking up at us, people who by chance have different-coloured skins from ours, and are rather hungry. Do you wonder that they don't like us all that much? Do you wonder that we sometimes feel ashamed of ourselves as we look out through the plate gla.s.s?

Well, it is within our power to get started on that problem. We are morally impelled to. We all know that, if the human species does solve that one, there will be consequences which are themselves problems. For instance, the population of the world will become embarra.s.singly large. But that is another challenge. There are going to be challenges to our intelligence and to our moral nature as long as man remains man. After all, a challenge is not, as the word is coming to be used, an excuse for slinking off and doing nothing. A challenge is something to be picked up.

For all those reasons, I believe the world community of scientists has a final responsibility upon it a greater responsibility than is pressing on any other body of men. I do not pretend to know how they will bear this responsibility. These may be famous last words, but I have an inextinguishable hope. For, as I have said tonight, there is no doubt that the scientific activity is both beautiful and truthful. I cannot prove it, but I believe that, simply because scientists cannot escape their own knowledge, they won't be able to avoid showing themselves disposed to good.

Acknowledgements.

Thanks to Nigel Henbest for his invaluable a.s.sistance as scientific adviser. Einstein's letter to President Roosevelt is reproduced by kind permission of the Estate of Albert Einstein. 'The Moral Un-neutrality of Science' first appeared in Public Affairs, published by Macmillan in 1971.

Endnotes

[1] See Appendix I for C. P. Snow's editorial in Discovery magazine, September 1939.

[2] See Appendix II.

Synopses (Both Series & 'Stand-alone' t.i.tles)

Published by House of Stratus A. Strangers and Brothers Series (series order) These t.i.tles can be read as a series, or randomly as stand-alone novels George Pa.s.sant

In the first of the Strangers and Brothers series Lewis Eliot tells the story of George Pa.s.sant, a Midland solicitor's managing clerk and idealist who tries to bring freedom to a group of people in the years 1925 to 1933.

The Light & The Dark