J. Robert Oppenheimer
SPEECH TO THE ASSOCIATION OF LOS ALAMOS SCIENTISTS
Los Alamos, November 2, 1945

I am grateful to the Executive Committee for this chance to talk to you. I should like to talk tonight -- if some of you have long memories perhaps you will regard it as justified -- as a fellow scientist, and at least as a fellow worrier about the fix we are in. I do not have anything very radical to say, or anything that will strike most of you with a great flash of enlightenment. I don't have anything to say that will be of an immense encouragement. In some ways I would have liked to talk to you at an earlier date -- but I couldn't talk to you as a Director. I could not talk, and will not tonight talk, too much about the practical political problems which are involved. There is one good reason for that -- I don't know very much about practical politics. And there is another reason, which has to some extent restrained me in the past. As you know, some of us have been asked to be technical advisors to the Secretary of War, and through him to the President. In the course of this we have naturally discussed things that were on our minds and have been made, often very willingly, the recipient of confidences; it is not possible to speak in detail about what Mr. A thinks and Mr. B doesn't think, or what is going to happen next week, without violating these confidences. I don't think that's important. I think there are issues which are quite simple and quite deep, and which involve us as a group of scientists -- involve us more, perhaps than any other group in the world. I think that it can only help to look a little at what our situation is -- at what has happened to us -- and that this must give us some honesty, some insight, which will be a source of strength in what may be the not-too-easy days ahead. I would like to take it as deep and serious as I know how, and then perhaps come to more immediate questions in the course of the discussion later. I want anyone who feels like it to ask me a question and if I can't answer it, as will often be the case, I will just have to say so.

What has happened to us -- it is really rather major, it is so major that I think in some ways one returns to the greatest developments of the twentieth century, to the discovery of relativity, and to the whole development of atomic theory and its interpretation in terms of complementarity, for analogy. These things, as you know, forced us to re-consider the relations between science and common sense. They forced on us the recognition that the fact that we were in the habit of talking a certain language and using certain concepts did not necessarily imply that there was anything in the real world to correspond to these. They forced us to be prepared for the inadequacy of the ways in which human beings attempted to deal with reality, for that reality. In some ways I think these virtues, which scientists quite reluctantly were forced to learn by the nature of the world they were studying, may be useful even today in preparing us for somewhat more radical views of what the issues are than would be natural or easy for people who had not been through this experience.

But the real impact of the creation of the atomic bomb and atomic weapons -- to understand that one has to look further back, look, I think, to the times when physical science was growing in the days of the renaissance, and when the threat that science offered was felt so deeply throughout the Christian world. The analogy is, of course, not perfect. You may even wish to think of the days in the last century when the theories of evolution seemed a threat to the values by which men lived. The analogy is not perfect because there is nothing in atomic weapons -- there is certainly nothing that we have done here or in the physics or chemistry that immediately preceded our work here -- in which any revolutionary ideas were involved. I don't think that the conceptions of nuclear fission have strained any man's attempts to understand them, and I don't feel that any of us have really learned in a deep sense very much from following this up. It is in a quite different way. It is not an idea -- it is a development and a reality -- but it has in common with the early days of physical science the fact that the very existence of science is threatened, and its value is threatened. This is the point that I would like to speak a little about.

I think that it hardly needs to be said why the impact is so strong. There are three reasons: one is the extraordinary speed with which things which were right on the frontier of science were translated into terms where they affected many living people, and potentially all people. Another is the fact, quite accidental in many ways, and connected with the speed, that scientists themselves played such a large part, not merely in providing the foundation for atomic weapons, but in actually making them. In this we are certainly closer to it than any other group. The third is that the thing we made -- partly because of the technical nature of the problem, partly because we worked hard, partly because we had good breaks -- really arrived in the world with such a shattering reality and suddenness that there was no opportunity for the edges to be worn off.

In considering what the situation of science is, it may be helpful to think a little of what people said and felt of their motives in coming into this job. One always has to worry that what people say of their motives is not adequate. Many people said different things, and most of them, I think, had some validity. There was in the first place the great concern that our enemy might develop these weapons before we did, and the feeling -- at least, in the early days, the very strong feeling -- that without atomic weapons it might be very difficult, it might be an impossible, it might be an incredibly long thing to win the war. These things wore off a little as it became clear that the war would be won in any case. Some people, I think, were motivated by curiosity, and rightly so; and some by a sense of adventure, and rightly so. Others had more political arguments and said, "Well, we know that atomic weapons are in principle possible, and it is not right that the threat of their unrealized possibility should hang over the world. It is right that the world should know what can be done in their field and deal with it." And the people added to that that it was a time when all over the world men would be particularly ripe and open for dealing with this problem because of the immediacy of the evils of war, because of the universal cry from everyone that one could not go through this thing again, even a war without atomic bombs. And there was finally, and I think rightly, the feeling that there was probably no place in the world where the development of atomic weapons would have a better chance of leading to a reasonable solution, and a smaller chance of leading to disaster, than within the United States. I believe all these things that people said are true, and I think I said them all myself at one time or another.

But when you come right down to it the reason that we did this job is because it was an organic necessity. If you are a scientist you cannot stop such a thing. If you are a scientist you believe that it is good to find out how the world works; that it is good to find out what the realities are; that it is good to turn over to mankind at large the greatest possible power to control the world and to deal with it according to its lights and its values.

There has been a lot of talk about the evil of secrecy, of concealment, of control, of security. Some of that talk has been on a rather low plane, limited really to saying that it is difficult or inconvenient to work in a world where you are not free to do what you want. I think that the talk has been justified, and that the almost unanimous resistance of scientists to the imposition of control and secrecy is a justified position, but I think that the reason for it may lie a little deeper. I think that it comes from the fact that secrecy strikes at the very root of what science is, and what it is for. It is not possible to be a scientist unless you believe that it is good to learn. It is not good to be a scientist, and it is not possible, unless you think that it is of the highest value to share your knowledge, to share it with anyone who is interested. It is not possible to be a scientist unless you believe that the knowledge of the world, and the power which this gives, is a thing which is of intrinsic value to humanity, and that you are using it to help in the spread of knowledge, and are willing to take the consequences. And, therefore, I think that this resistance which we feel and see all around us to anything which is an attempt to treat science of the future as though it were rather a dangerous thing, a thing that must be watched and managed, is resisted not because of its inconvenience -- I think we are in a position where we must be willing to take any inconvenience -- but resisted because it is based on a philosophy incompatible with that by which we live, and have learned to live in the past.

There are many people who try to wiggle out of this. They say the real importance of atomic energy does not lie in the weapons that have been made; the real importance lies in all the great benefits which atomic energy, which the various radiations, will bring to mankind. There may be some truth in this. I am sure that there is truth in it, because there has never in the past been a new field opened up where the real fruits of it have not been invisible at the beginning. I have a very high confidence that the fruits -- the so-called peacetime applications -- of atomic energy will have in them all that we think, and more. There are others who try to escape the immediacy of this situation by saying that, after all, war has always been very terrible; after all, weapons have always gotten worse and worse; that this is just another weapon and it doesn't create a great change; that they are not so bad; bombings have been bad in this war and this is not a change in that -- it just adds a little to the effectiveness of bombing; that some sort of protection will be found. I think that these efforts to diffuse and weaken the nature of the crisis make it only more dangerous. I think it is for us to accept it as a very grave crisis, to realize that these atomic weapons which we have started to make are very terrible, that they involve a change, that they are not just a slight modification: to accept this, and to accept with it the necessity for those transformations in the world which will make it possible to integrate these developments into human life.

As scientists I think we have perhaps a little greater ability to accept change, and accept radical change, because of our experiences in the pursuit of science. And that may help us -- that, and the fact that we have lived with it -- to be of some use in understanding these problems.

It is clear to me that wars have changed. It is clear to me that if these first bombs -- the bomb that was dropped on Nagasaki -- that if these can destroy ten square miles, then that is really quite something. It is clear to me that they are going to be very cheap if anyone wants to make them; it is clear to me that this is a situation where a quantitative change, and a change in which the advantage of aggression compared to defense -- of attack compared to defense -- is shifted, where this quantitative change has all the character of a change in quality, of a change in the nature of the world. I know that whereas wars have become intolerable, and the question would have been raised and would have been pursued after this war, more ardently than after the last, of whether there was not some method by which they could be averted. But I think the advent of the atomic bomb and the facts which will get around that they are not too hard to make -- that they will be universal if people wish to make them universal, that they will not constitute a real drain on the economy of any strong nation, and that their power of destruction will grow and is already incomparably greater than that of any other weapon -- I think these things create a new situation, so new that there is some danger, even some danger in believing, that what we have is a new argument for arrangements, for hopes, that existed before this development took place. By that I mean that much as I like to hear advocates of a world federation, or advocates of a United Nations organization, who have been talking of these things for years -- much as I like to hear them say that here is a new argument, I think that they are in part missing the point, because the point is not that atomic weapons constitute a new argument. There have always been good arguments. The point is that atomic weapons constitute also a field, a new field, and a new opportunity for realizing preconditions. I think when people talk of the fact that this is not only a great peril, but a great hope, this is what they should mean. I do not think they should mean the unknown, though sure, value of industrial and scientific virtues of atomic energy, but rather the simple fact that in this field, because it is a threat, because it is a peril, and because it has certain special characteristics, to which I will return, there exists a possibility of realizing, of beginning to realize, those changes which are needed if there is to be any peace.

Those are very far-reaching changes. They are changes in the relations between nations, not only in spirit, not only in law, but also in conception and feeling. I don't know which of these is prior; they must all work together, and only the gradual interaction of one on the other can make a reality. I don't agree with those who say the first step is to have a structure of international law. I don't agree with those who say the only thing is to have friendly feelings. All of these things will be involved. I think it is true to say that atomic weapons are a peril which affect everyone in the world, and in that sense a completely common problem, as common a problem as it was for the Allies to defeat the Nazis. I think that in order to handle this common problem there must be a complete sense of community responsibility. I do not think that one may expect that people will contribute to the solution of the problem until they are aware of their ability to take part in the solution. I think that it is a field in which the implementation of such a common responsibility has certain decisive advantages. It is a new field, in which the position of vested interests in various parts of the world is very much less serious than in others. It is serious in this country, and that is one of our problems. It is a new field, in which the role of science has been so great that it is to my mind hardly thinkable that the international traditions of science, and the fraternity of scientists, should not play a constructive part. It is a new field, in which just the novelty and the special characteristics of the technical operations should enable one to establish a community of interest which might almost be regarded as a pilot plant for a new type of international collaboration. I speak of it as a pilot plant because it is quite clear that the control of atomic weapons cannot be in itself the unique end of such operation. The only unique end can be a world that is united, and a world in which war will not occur. But those things don't happen overnight, and in this field it would seem that one could get started, and get started without meeting those insuperable obstacles which history has so often placed in the way of any effort of cooperation. Now, this is not an easy thing, and the point I want to make, the one point I want to hammer home, is what an enormous change in spirit is involved. There are things which we hold very dear, and I think rightly hold very dear; I would say that the word democracy perhaps stood for some of them as well as any other word. There are many parts of the world in which there is no democracy. There are other things which we hold dear, and which we rightly should. And when I speak of a new spirit in international affairs I mean that even to these deepest of things which we cherish, and for which Americans have been willing to die -- and certainly most of us would be willing to die -- even in these deepest things, we realize that there is something more profound than that; namely, the common bond with other men everywhere. It is only if you do that that this makes sense; because if you approach the problem and say, "We know what is right and we would like to use the atomic bomb to persuade you to agree with us," then you are in a very weak position and you will not succeed, because under those conditions you will not succeed in delegating responsibility for the survival of men. It is a purely unilateral statement; you will find yourselves attempting by force of arms to prevent a disaster.

I want to express the utmost sympathy with the people who have to grapple with this problem and in the strongest terms to urge you not to underestimate its difficulty. I can think of an analogy, and I hope it is not a completely good analogy: in the days in the first half of the nineteenth century there were many people, mostly in the North, but some in the South, who thought that there was no evil on earth more degrading than human slavery, and nothing that they would more willingly devote their lives to than its eradication. Always when I was young I wondered why it was that when Lincoln was President he did not declare that the war against the South, when it broke out, was a war that slavery should be abolished, that this was the central point, the rallying point, of that war. Lincoln was severely criticized by many of the Abolitionists as you know, by many then called radicals, because he seemed to be waging a war which did not hit the thing that was most important. But Lincoln realized, and I have only in the last months come to appreciate the depth and wisdom of it, that beyond the issue of slavery was the issue of the community of the people of the country, and the issue of the Union. I hope that today this will not be an issue calling for war; but I wanted to remind you that in order to preserve the Union Lincoln had to subordinate the immediate problem of the eradication of slavery, and trust -- and I think if he had had his way it would have gone so -- to the conflict of these ideas in a united people to eradicate it.

These are somewhat general remarks and it may be appropriate to say one or two things that are a little more programmatic, that are not quite so hard to get one's hands on. That is, what sort of agreement between nations would be a reasonable start. I don't know the answer to this, and I am very sure that no a priori answer should be given, that it is something that is going to take constant working out. But I think it is a thing where it will not hurt to have some reasonably concrete proposal. And I would go a step further and say of even such questions as the great question of secrecy -- which perplexes scientists and other people -- that even this was not a suitable subject for unilateral action. If atomic energy is to be treated as an international problem, as I think it must be, if it is to be treated on the basis of an international responsibility and an international common concern, the problems of secrecy are also international problems. I don't mean by that that our present classifications and our present, in many cases inevitably ridiculous, procedures should be maintained. I mean that the fundamental problem of how to treat this peril ought not to be treated unilaterally by the United States, or by the United States in conjunction with Great Britain.

The first thing I would say about any proposals is that they ought to be regarded as interim proposals, and that whenever they are made it be understood and agreed that within a year or two years -- whatever seems a reasonable time -- they will be reconsidered and the problems which have arisen, and the new developments which have occurred, will cause a rewriting. I think the only point is that there should be a few things in these proposals which will work in the right direction, and that the things should be accepted without forcing all of the changes, which we know must ultimately occur, upon people who will not be ready for them. This is anyone's guess, but it would seem to me that if you took these four points, it might work: first, that we are dealing with an interim solution, so recognized. Second, that the nations participating in the arrangement would have a joint atomic energy commission, operating under the most broad directives from the different states, but with a power which only they had, and which was not subject to review by the heads of State, to go ahead with those constructive applications of atomic energy which we would all like to see developed -- energy sources, and the innumerable research tools which are immediate possibilities. Third, that there would be not merely the possibility of exchange of scientists and students; that very, very concrete machinery more or less forcing such exchange should be established, so that we would be quite sure that the fraternity of scientists would be strengthened and that the bonds on which so much of the future depends would have some reinforcement and some scope. And fourth, I would say that no bombs be made. I don't know whether these proposals are good ones, and I think that anyone in this group would have his own proposals. But I mention them as very simple things, which I don't believe solve the problem, and which I want to make clear are not the ultimate or even a touch of the ultimate, but which I think ought to be started right away; which I believe -- though I know very little of this -- may very well be acceptable to any of the nations that wish to become partners with us in this great undertaking.

One of the questions which you will want to hear more about, and which I can only partly hope to succeed in answering, is to what extent such views -- essentially the view that the life of science is threatened, the life of the world is threatened, and that only [by] a profound revision of what it is that constitutes a thing worth fighting for and a thing worth living for can this crisis be met -- to what extent these views are held by other men. They are certainly not held universally by scientists; but I think they are in agreement with all of the expressed opinions of this group, and I know that many of my friends here see pretty much eye to eye. I would speak especially of Bohr, who was here so much during the difficult days, who had many discussions with us, and who helped us reach the conclusion that [it was] not only a desirable solution, but that it was the unique solution, that there were no other alternatives.

I would say that among scientists there are certain centrifugal tendencies which seem to me a little dangerous, but not very. One of them is the attempt to try, in this imperilled world, in which the very function of science is threatened, to make convenient arrangements for the continuance of science, and to pay very little attention to the preconditions which give sense to it. Another is the tendency to say we must have a free science and a strong science, because this will make us a strong nation and enable us to fight better wars. It seems to me that this is a profound mistake, and I don't like to hear it. The third is even odder, and it is to say, "Oh give the bombs to the United Nations for police purposes, and let us get back to physics and chemistry." I think none of these are really held very widely, but they show that there are people who are desperately trying to avoid what I think is the most difficult problem. One must expect these false solutions, and overeasy solutions, and these are three which pop up from time to time.

As far as I can tell in the world outside there are many people just as quick to see the gravity of the situation, and to understand it in terms not so different from those I have tried to outline. It is not only among scientists that there are wise people and foolish people. I have had occasion in the last few months to meet people who had to do with the Government -- the legislative branches, the administrative branches, and even the judicial branches, and I have found many in whom an understanding of what this problem is, and of the general lines along which it can be solved, is very clear. I would especially mention the former Secretary of War, Mr. Stimson, who, perhaps as much as any man, seemed to appreciate how hopeless and how impractical it was to attack this problem on a superficial level, and whose devotion to the development of atomic weapons was in large measure governed by his understanding of the hope that lay in it that there would be a new world. I know this is a surprise, because most people think that the War Department has as its unique function the making of war. The Secretary of War has other functions.

I think this is another question of importance: that is, what views will be held on these matters in other countries. I think it is important to realize that even those who are well informed in this country have been slow to understand, slow to believe that the bombs would work, and then slow to understand that their working would present such profound problems. We have certain interests in playing up the bomb, not only we here locally, but all over the country, because we made them, and our pride is involved. I think that in other lands it may be even more difficult for an appreciation of the magnitude of the thing to take hold. For this reason, I'm not sure that the greatest opportunities for progress do not lie somewhat further in the future than I had for a long time thought.

There have been two or three official statements by the President which defined, as nearly as their in some measure inevitable contradictions made possible, the official policy of the Government. And I think that one must not be entirely discouraged by the fact that there are contradictions, because the contradictions show that the problem is being understood as a difficult one, is temporarily being regarded as an insoluble one. Certainly you will notice, especially in the message to Congress, many indications of a sympathy with, and an understanding of, the views which this group holds, and which I have discussed briefly tonight. I think all of us were encouraged at the phrase "too revolutionary to consider in the framework of old ideas." That's about what we all think. I think all of us were encouraged by the sense of urgency that was frequently and emphatically stressed. I think all of us must be encouraged by the recognition, the official recognition by the Government of the importance -- of the overriding importance -- of the free exchange of scientific ideas and scientific information between all countries of the world. It would certainly be ridiculous to regard this as a final end, but I think that it would also be a very dangerous thing not to realize that it as a precondition. I am myself somewhat discouraged by the limitation of the objective to the elimination of atomic weapons, and I have seen many articles -- probably you have, too -- in which this is interpreted as follows: "Let us get international agreement to outlaw atomic weapons and then let us go back to having a good, clean war." This is certainly not a very good way of looking at it. I think, to say it again, that if one solves the problems presented by the atomic bomb, one will have made a pilot plant for solution of the problem of ending war.

But what is surely the thing which must have troubled you, and which troubled me, in the official statements was the insistent note of unilateral responsibility for the handling of atomic weapons. However good the motives of this country are -- I am not going to argue with the President's description of what the motives and the aims are -- we are 140 million people, and there are two billion people living on earth. We must understand that whatever our commitments to our own views and ideas, and however confident we are that in the course of time they will tend to prevail, our absolute -- our completely absolute -- commitment to them, in denial of the views and ideas of other people, cannot be the basis of any kind of agreement.

As I have said, I had for a long time the feeling of the most extreme urgency, and I think maybe there was something right about that. There was a period immediately after the first use of the bomb when it seemed most natural that a clear statement of policy, and the initial steps of implementing it, should have been made; and it would be wrong for me not to admit that something may have been lost, and that there may be tragedy in that loss. But I think the plain fact is that in the actual world, and with the actual people in it, it has taken time, and it may take longer, to understand what this is all about. And I am not sure, as I have said before, that in other lands it won't take longer than it does in this country. As it is now, our only course is to see what we can do to bring about an understanding on a level deep enough to make a solution practicable, and to do that without undue delay.

One may think that the views suggested in the President's Navy Day speech are not entirely encouraging, that many men who are more versed than we in the practical art of statesmanship have seen more hope in a radical view, which may at first sight seem visionary, than in an approach on a more conventional level.

I don't have very much more to say. There are a few things which scientists perhaps should remember, that I don't think I need to remind us of; but I will, anyway. One is that they are very often called upon to give technical information in one way or another, and I think one cannot be too careful to be honest. And it is very difficult, not because one tells lies, but because so often questions are put in a form which makes it very hard to give an answer which is not misleading. I think we will be in a very weak position unless we maintain at its highest the scrupulousness which is traditional for us in sticking to the truth, and in distinguishing between what we know to be true from what we hope may be true.

The second thing I think it right to speak of is this: it is everywhere felt that the fraternity between us and scientists in other countries may be one of the most helpful things for the future; yet it is apparent that even in this country not all of us who are scientists are in agreement. There is no harm in that; such disagreement is healthy. But we must not lose the sense of fraternity because of it; we must not lose our fundamental confidence in our fellow scientists.

I think that we have no hope at all if we yield in our belief in the value of science, in the good that it can be to the world to know about reality, about nature, to attain a gradually greater and greater control of nature, to learn, to teach, to understand. I think that if we lose our faith in this we stop being scientists, we sell out our heritage, we lose what we have most of value for this time of crisis.

But there is another thing: we are not only scientists; we are men, too. We cannot forget our dependence on our fellow men. I mean not only our material dependence, without which no science would be possible, and without which we could not work; I mean also our deep moral dependence, in that the value of science must lie in the world of men, that all our roots lie there. These are the strongest bonds in the world, stronger than those even that bind us to one another, these are the deepest bonds -- that bind us to our fellow men.


Oppenheimer refers approvingly at one point to a speech by Harry S Truman -- he writes, "I think all of us were encouraged at the phrase 'too revolutionary to consider in the framework of old ideas'." The full text of Truman's speech is available elsewhere on this website.