01UndatedIf someone were to propose that the planets go around the sun because all planet matter has a kind of tendency for movement, a kind of motility, let us call it an ‘oomph,’ this theory could explain a number of other phenomena as well. So this is a good theory, is it not? No. It is nowhere near as good as the proposition that the planets move around the sun under the influence of a central force which varies exactly inversely as the square of the distance from the center. The second theory is better because it is so specific; it is so obviously unlikely to be the result of chance. It is so definite that the barest error in the movement can show that it is wrong; but the planets could wobble all over the place, and, according to the first theory, you could say, ‘Well, that is the funny behavior of the ‘oomph.Richard Feynman / quote ↗
02UndatedI 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.Richard Feynman / quote ↗
03UndatedI happen to know this, and I happen to know that, and maybe I know that;and I work everything out from there. Tomorrow I may forgot that this is true, but remember that something else is true, so I can reconstruct it all again. I am never quite sure of where I am supposed to begin or where I am supposed to end. I just remember enough all the time so that as the memory fades and some of the pieces fall out I can put the thing back together again every dayRichard Feynman / quote ↗
04UndatedWords can be meaningless. If they are used in such a way that no sharp conclusions can be drawn.Richard Feynman / quote ↗
06UndatedYou have no responsibility to live up to what other people think you ought to accomplish. I have no responsibility to be like they expect me to be. It's their mistake, not my failing.Richard Feynman / quote ↗
07UndatedI learned from her that every woman is worriedabout her looks, no matter how beautiful she is.Richard Feynman / quote ↗
08UndatedA few years after I gave some lectures for the freshmen at Caltech (which were published as the Feynman Lectures on Physics), I received a long letter from a feminist group. I was accused of being anti-women because of two stories: the first was a discussion of the subtleties of velocity, and involved a woman driver being stopped by a cop. There's a discussion about how fast she was going, and I had her raise valid objections to the cop's definitions of velocity. The letter said I was making the women look stupid. The other story they objected to was told by the great astronomer Arthur Eddington, who had just figured out that the stars get their power from burning hydrogen in a nuclear reaction producing helium. He recounted how, on the night after his discovery, he was sitting on a bench with his girlfriend. She said, "Look how pretty the stars shine!" To which he replied, "Yes, and right now, I'm the only man in the world who knows how they shine." He was describing a kind of wonderful loneliness you have when you make a discovery. The letter claimed that I was saying a women is incapable of understanding nuclear reactions. I figured there was no point in trying to answer their accusations in detail, so I wrote a short letter back to them: "Don't bug me, Man!Richard Feynman / quote ↗
09UndatedI believe, therefore, that although it is not the case today, that there may some day come a time, I should hope, when it will fully appreciated that the power of governments should be limited; that governments ought not to be empowered to decide the validity of scientific theories, that this is a ridiculous thing for them to try to do; that they are not to decide the description of history or of economic theory or of philosophy.Richard Feynman / quote ↗
10UndatedYou can’t say A is made of B or vice versa. All mass is interaction.Richard Feynman / quote ↗
11UndatedI took a little walk outside for a while. I was surprised that I wasn't feeling what I thought people were supposed to feel under the circumstances. May be I was fooling myself. I wasn't delighted, but I didn't feel terribly upset, perhaps because we had known for a long time that it was going to happen.It's hard to explain. If a Martian(who, we'll imagine never dies except by accident) came to Earth and saw this peculiar race of creatures-these humans who live about seventy or eighty years, knowing that death is going to come--it would look to hi like a terrible problem of psychology to live under those circumstances, knowing that life is only temporary Well, we humans somehow figure out how to live despite this problem: we laugh, we joke, we live.The only difference for me and Arlene was, instead of fifty years, it was five years. It was only a quantitative difference--the psychological problem was just the same. The only way it would have become any different is if we had said to ourselves, "But those other people have it better, because they might live fifty years." But that's crazy. Why make yourself miserable saying things like, "Why do we have such bad luck? What has God done to us? What have we done to deserve this?"--all of which, if you understand reality and take it completely into your heart, are irrelevant and unsolvable. They are just things that nobody can know. Your situation is just an accident of life..We had a hell of good time together...Richard Feynman / quote ↗
12UndatedThis is not a new idea; this is the idea of the age of reason. This is the philosophy that guided the men that made the democracy that we live under. The idea that no one really knew how to run a government led to the idea that we should arrange a system by which new ideas could be developed, tried out, and tossed out if necessary, with more new ideas brought in—a trial and error system.Richard Feynman / quote ↗
13UndatedI noticed that the [drawing] teacher didn't tell people much... Instead, he tried to inspire us to experiment with new approaches. I thought of how we teach physics: We have so many techniques - so many mathematical methods - that we never stop telling the students how to do things. On the other hand, the drawing teacher is afraid to tell you anything. If your lines are very heavy, the teacher can't say, "Your lines are too heavy." because *some* artist has figured out a way of making great pictures using heavy lines. The teacher doesn't want to push you in some particular direction. So the drawing teacher has this problem of communicating how to draw by osmosis and not by instruction, while the physics teacher has the problem of always teaching techniques, rather than the spirit, of how to go about solving physical problems.Richard Feynman / quote ↗
14UndatedThe scientist has a lot of experience with ignorance and doubt and uncertainty, and this experience is of very great importance, I think. When a scientist doesn’t know the answer to a problem, he is ignorant. When he has a hunch as to what the result is, he is uncertain. And when he is pretty damn sure of what the result is going to be, he is still in some doubt. We have found it of paramount importance that in order to progress, we must recognize our ignorance and leave room for doubt. Scientific knowledge is a body of statements of varying degrees of certainty — some most unsure, some nearly sure, but none absolutely certain. Now, we scientists are used to this, and we take it for granted that it is perfectly consistent to be unsure, that it is possible to live and not know. But I don’t know whether everyone realizes this is true. Our freedom to doubt was born out of a struggle against authority in the early days of science. It was a very deep and strong struggle: permit us to question — to doubt — to not be sure. I think that it is important that we do not forget this struggle and thus perhaps lose what we have gained.Richard Feynman / quote ↗
16UndatedDetails that could throw doubt on your interpretation must be given, if you know them. You must do the best you can—if you know anything at all wrong, or possibly wrong—to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition.Richard Feynman / quote ↗
17UndatedIf I could explain it to the average person, I wouldn't have been worth the Nobel Prize.Richard Feynman / quote ↗
18UndatedI suddenly remembered that Murray Gell-Mann and I were supposed to give talks at that conference on the present situation of high-energy physics. My talk was set for the plenary session, so I asked the guide, "Sir, where would the talks for the plenary session of the conference be?""Back in that room that we just came through.""Oh!" I said in delight. "Then I'm gonna give a speech in that room!"The guide looked down at my dirty pants and my sloppy shirt. I realized how dumb that remark must have sounded to him, but it was genuine surprise and delight on my part. We went along a little bit farther, and the guide said, "This is a lounge for the various delegates, where they often hold informal discussions." They were some small, square windows in the doors to the lounge that you could look through, so people looked in. There were a few men sitting there talking. I looked through the windows and saw Igor Tamm, a physicist from Russia that I know. "Oh!" I said. "I know that guy!" and I started through the door.The guide screamed, "No, no! Don't go in there!" By this time he was sure he had a maniac on his hands, but he couldn't chase me because he wasn't allowed to go through the door himself!Richard Feynman / quote ↗
19UndatedPhysicists like to think that all you have to do is say, these are the conditions, now what happens next?Richard Feynman / quote ↗
20UndatedThe next question was — what makes planets go around the sun? At the time of Kepler some people answered this problem by saying that there were angels behind them beating their wings and pushing the planets around an orbit. As you will see, the answer is not very far from the truth. The only difference is that the angels sit in a different direction and their wings push inward.Richard Feynman / quote ↗
21UndatedThe laws of physics could be like an onion, with new laws becoming operational as we probe new scales. We simply don't know!Richard Feynman / quote ↗
23UndatedI can live with doubt and uncertainty and not knowing. I think it's much more interesting to live not knowing than to have answers that might be wrong.Richard Feynman / quote ↗