"What do I know of religion and politics? Several friends in the physics departments here and in other places laughed and said, 'I'd like to come and hear what you have to say. I never knew you were interested very much in those things.' They mean, of course, I am interested, but I would not dare talk about them.

In talking about the impact of ideas in field on ideas in another field, one is always apt to make a fool of oneself. In these days of specialization there are there are too few people who have such a deep understanding of two departments of our knowledge that they do no make fools of themselves or the other.

The ideas I wish to describe are old ideas There is practically nothing that I am going to say tonight that could not have easily been said by philosophers of the seventeenth century. Why repeat all this? Because there are new generations born every day. Because there are great ideas developed in the history of man, and these ideas do not last unless the are passed purposely and clearly from generation to generation." (3-4)

"What is science? The word is usually used to mean one of three things, or a mixture of them. I do not think we need to be precise— it is not always a good idea to be too precise. Science means, sometimes, a special method of finding things out. Sometimes is means the body of knowledge arising from the things found out. It may also mean the new things you can do when you have found something out, or the actual doing of new things. This last field is usually called technology— but if you look at the science section in Time magazine you will find it covers about 50 percent what new things are found out and about 50 percent what new things can be and are being done. And so the popular definition of science is partly technology, too." (4-5)

"The most obvious characteristic of science is its application, the fact that as a consequence of science one has a power to do things. And the effect of this power had need hardly be mentioned. The whole industrial revolution would almost have been impossible without the development of science. The possibilities today of producing quantities of food adequate for such a large population, of controlling sickness— the very fact that there can be free men without the necessity of slavery for full production— are very likely the result of the development of scientific means of production.

Now this power to do things carries with it no instructions on how to use it, whether to use it, whether to use it for good or for evil. The product of this power is either good or evil, depending on how it is used. We like improved production, but we have problems with automation. We are happy with the development of medicine, and then we worry about the number of births and the fact that no one dies from the diseases we have eliminated. Or else, with the same knowledge of bacteria, we have hidden laboratories in which men are working as hard as they can to develop bacteria for which no one else will be able to find a cure. We are happy with the development of air transportation and are impressed by the great airplanes, but are also aware of the severe horrors of air war. We are pleased by the ability to communicate between nations, and then we worry about the fact that we can be snooped upon so easily. We are excited by the fact that space can now be entered; well, we will undoubtedly have a difficulty there too. The most famous of these imbalances is the development of nuclear energy and its obvious problems.

Is science of any value?

I think a power to do something is of value. Whether the result is a good thing or a bad thing depends on how it is used, but the power is a value.

One in Hawaii I was taken to a Buddhist temple. In the temple a man said,  'I am going to tell you something that you will never forget.' And then he said, 'To every man is given the key to the gates of heaven. The same key will open the gates of hell.'

And so it is with science. In a way it is the key to the gates of heaven, and the same key opens the gates of hell, and we do not have any instructions as to which is which gate. Shall we throw away the key and never have a way to enter the gates of heaven? Or shall we struggle with the problem of which is the best way to use the key? That is, of course, a very serious question, but I think that we cannot deny the value of the key to the gates of heaven." (5-7)

"The next aspect of science is its contents, the things that have been found out. This is the yield. This is the gold. This is the excitement, the pay you get for all the disciplined thinking and hard work. The work is not done for the sake of an application. It is done for the excitement of what is found out. Perhaps most of you know this. But to those of you who do not know it, it is almost impossible for me to convey in a lecture this important aspect, this exciting part, the real reason for science. And without understanding this you miss the whole point. You cannot understand science and its relation to anything else unless you understand and appreciate the great adventure of our time. You do not live in your time unless you understand that this is a tremendous adventure and a wild and exciting thing. " (9)

"And it has been discovered that all the world is made of the same atoms, that the stars are of the same stuff as ourselves. It then becomes a question of where our stuff came from. Not just where did life come from, or where did the earth come from, but where did the stuff of life and earth come from? It looks as if it was belched from some exploding star, much as some of the stars are exploding now. So this piece of dirt waits four and a half billion years and evolves and changes, and now a strange creature stands here with instruments and talks to the strange creatures in the audience. What a wonderful world!

Or take the physiology of human beings. It makes no difference what I talk about. If you look closely enough at anything, you will see that there is nothing more exciting than the truth, that pay dirt of the scientist, discovered by his painstaking efforts." (12-13)

"The exceptions to any rule are most interesting in themselves, for they show us that the old rule is wrong. And it is most exciting, then, to find out what the right rule, if any, is. The exception is studied, along with other conditions that produce similar effects. The scientist tries to find more exceptions and to determine the characteristics of the exceptions, a process that is continually exciting as it develops. He does not try to avoid showing that the rules are wrong; there is progress and excitement in the exact opposite. He tries to prove himself wrong as quickly as possible.

The principle that observation is the judge imposes a severe limitation to the kind of questions that can be answered. They are limited to questions that can be put this way: 'If I do this, what will happen?' There are ways to try it and see. Questions like, 'Should I do this?' and 'What is the value of this?' are not of the same kind." (16)

"Scientific reasoning requires a discipline, because even on the lowest level such errors are unnecessary today." (18)

"The rules that describe nature seem to be mathematical. This is not a result of the fact that observation is judge, and it is not a characteristic necessity of science that it be mathematical. It just turns out the you can state mathematical laws, in physics at least, which  work to make powerful predictions. Why nature is mathematical is, again, a mystery." (24)

"It has to be done because the extrapolations are the only things that have any real value. It is only the principle of what you think will happen in a case you have not tried that is worth knowing about. Knowledge is of no real value if all you can tell me is what happened yesterday. It is necessary to tell what will happen tomorrow if you do something— not only necessary, but fun. Only you must be willing to stick your neck out." (25)

"It is necessary and true that all of the things we say in science, all of the conclusions, are uncertain, because they are only conclusions. They are guesses as to what is going to happen, and you cannot know what will happen, because you have not made the most complete experiments." (26)

"I believe that to solve any problem that has never been solved before, you have to leave the door to the unknown ajar. You have to permit the possibility  that you do not have it exactly right. Otherwise, if you have made up your mind already, you might not solve it." (26-27)

"If we were not able or did not desire to look in any new direction, if we did not have a doubt or recognize ignorance, we would not get any new ideas. There would be nothing worth checking, because we would know what is true. So what we call scientific knowledge today is a body of statements of varying degrees of certainty." (27)

"How you get to know is what I want to know." (28)

"Why can't we conquer ourselves? Because we find that even the greatest  forces and abilities don't seem to carry with them any clear instructions on how to use them. As an example, the great accumulation of understanding as to how the physical world behaves only convinces one that this behavior has a kind of meaninglessness about it. The sciences do not directly teach good and bad." (32)

"Throughout all the ages, men have been trying to fathom the meaning of life. They realize that if some  direction or some meaning could be given to the whole thing, to our actions, then great human forces would be unleashed. So, very many answers have been given to the question of the meaning of it all. But they have all been of different sorts. And the proponents of one idea have looked with horror at the actions of the believers of another— horror because from a disagreeing point of view all the great potentialities of the race were being channeled into a false and confining blind alley. In fact, it is from the history of the enormous monstrosities that have been created by false belief that philosophers have come to realize the fantastic potentialities and wonderous capacities of human beings." (32-33)

"There are thousands of years in the past, and there is an unknown amount of time in the future. There are all kinds of opportunities, and there are all kinds of dangers. Man has been stopped before  by stopping his ideas. Man has been jammed for some long periods of time. We will not tolerate this. I hope for freedom for future generations— freedom to doubt, to develop, to continue the adventure of finding out new ways of doing things, of solving problems." (56)

"No government has the right to decide on the truth of scientific principles, nor to prescribe in any way the character of the questions investigated. Neither may a government determine the aetheitc value of artistic expression. Nor should it pronounce on the validity of economic, historic, religious, or philosophical doctrines. Instead it has a duty to its citizens to maintain freedom., to let those citizens contribute to the further adventure and the development of the human race." (57)

"The speed at which science has been developing  for the last two hundred years has been ever increasing, and we reach a culmination of speed now. We are in particular in the biological sciences, on the threshold of the most remarkable discoveries. What they are going to be I am unable to tell you. Naturally, this is the excitement of it. And the excitement that comes from turning one stone after another and finding underneath new discoveries has  been going on now perpetually for severeal hundred years, and it is and ever, rising crescendo. This is, in that sense, definitely a scientific age. It has been called a heroic age, by a scientist, of course. Nobody else knows about it. Sometime when history books look back at this age they will see that it was a most dramatic and remarkable age, the transformation from not knowing much about the world to knowing a great deal more than was known before. But if you mean that this is an age of science in the sense that  in art, in literature, and in people's attitudes and understandings, and so forth science plays a large part, I don't think it's a scientific age at all. You see, if you take the heroic age of the Greeks, say, there were poems about the military heroes. In the religious period of the Middle Ages, art was related directly to religion, and people's attitudes toward life were definitely  were definitely closely knit to religious viewpoints. It was a religious age. This is not a scientific age from that point of view." (62-63)

"This is in the attitude of the mind of the populace, that they have to have an answer and that a man who gives an answer is better than a man who gives no answer, when the real fact of the matter is, in most cases, it is the other way around. And the result of this of course is that the politician must give an answer. And the result of this is that political promises can never be kept. It is a mechanical fac; it is impossible. The result of that is that nobody believes campaign promises. And the result of that is a general disparaging of politics, a general lack of respect for the people who are trying to solve problems, and so forth. It's all generated from the very beginning (maybe— this is a simple analysis). It's all generated, maybe, by the fact that the attitude of the populace is to try to find the answer instead of trying to find a man who has a way of getting at the answer." (66)

"Anyway, there is an example of how to deal with uncertainty and how to look at something scientifically. To be prejudiced against mind reading a million to one does not mean that you can never be convinced that a man is a mind reader. The only way that you can never be convinced that a man is a mind reader is one of two things: If you are limited to a finite number of experiments, and he won't let you do any more, or if you are infinitely prejudiced at the beginning that it's absolutely impossible.

Now, another example of a test of truth, so to speak, that works that works in the sciences that would probably work in other fields to some extent is that if something is true, really so, if you continue observations and improve the effectiveness of the observations, the effects stand out more obviously. Not less obviously. That is, if there is something really there, and you can't see good because the glass is foggy, and you polish the glass and look clearer, then it's more obvious that it's there, not less." (71)

"I met a girl at about thirteen or fourteen whom I loved very much, and we took about thirteen years to get married. It's not my present wife, as you will see. And she got tuberculosis and had it, actually, for several years. And when she got tuberculosis I gave her a clock which had nice big numbers that turned over rather than ones with a dial, and she liked it. The day she got sick I gave it to her, and she kept it by the side of her bed for four, five, six years while she got sicker and sicker. And ultimately she died. She died at 9:22 in the evening. And the clock stopped at 9:22 in the evening and never went again. Fortunately, I noticed some part of the anecdote I have to tell you. After five years the clock gets kind os weak in the knees. Every once in a while I had to fix it, so the wheels were loose. And secondly, the nurse who had to write on the death certificate the time of death, because the light was so low in the room, took the clock and turned it up a little bit to see the numbers a little bit better and put it down. If I hadn't noticed that, again I would be in some trouble. So one must be very careful in such anecdotes to remember all the conditions, and even the ones that you don't notice may be the explanation of the mystery." (83)

"Not only are there faith healers on the radio, there are also radio religion people who use the Bible to predict all kinds of phenomena that are going to happen. I listened intrigued to a man who in a dream visited God and received all kinds of special information for his congregation, etc. Well, this unscientific age... But I don't know what to do with that one. I don't know what rule of reasoning to use to show right away that it's nutty. I think it belongs to a general lack of understanding of how complicated the world is and how elaborate and unlikely it is that such a thing would work." (94)

"What I am asking for in many directions is an abject honesty. It think that we should have a more abject honesty in political matters. And I think we'll be freer that way." (106)