Richard Feynman

“We can't define anything precisely. If we attempt to, we get into the paralysis of thought that comes to philosophers... one saying to the other: you don't know what you are talking about! The second one says: what do you mean by talking? What do you mean by you? What do you mean by know?”

“Everything is interesting if you go into it deeply enough”

“Nature has a great simplicity and therefore a great beauty”

“Why nature is mathematical is, again, a mystery.”

“It doesn't make a difference how beautiful your guess is. It doesn't make a difference how smart you are, who made the guess, or what his name is. If it disagrees with experiment, it's wrong.”

“I was terrible in English. I couldn't stand the subject. It seemed to me ridiculous to worry about whether you spelled something wrong or not, because English spelling is just a human convention--it has nothing to do with anything real, anything from nature. Any word can be spelled just as well a different way.”

“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 him 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.”

“All mass is interaction.”

“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.”

“If u think u can u mayif u think u can't u r right”

“I'm smart enough to know that I'm dumb.”

“Science is a way of trying not to fool yourself. The principle is that you must not fool yourself, and you are the easiest person to fool.”

“There is no authority who decides what is a good idea.”

“It was thought in the Middle Ages that people simply make many observations, and the observations themselves suggest the laws. But it does not work that way. It takes much more imagination than that.So the next thing we have to talk about is where the new ideas come from. Actually, it does not make any difference, as long as they come.”

“To every man is given the key to the gates of heaven. The same key opens the gates of hell. And so it is with science.”

“Of course, you only live one life, and you make all your mistakes, and learn what not to do, and that's the end of you.”

“There is nothing that living things do that cannot be understood from the point of view that they are made of atoms acting according to the laws of physics.”

“Science is what we have learned about how to keep from fooling ourselves.”

“If I could explain it to the average person, I wouldn't have been worth the Nobel Prize.”

“Odiaría morir dos veces, sería tan aburrido!.”

“i have a friend who’s an artist and he’s sometimes taken a view which i don’t agree with very well. he’ll hold up a flower and say, “look how beautiful it is,” and i’ll agree, i think. and he says - “you see, i as an artist can see how beautiful this is, but you as a scientist, oh, take this all apart and it becomes a dull thing.” and i think that he’s kind of nutty. first of all, the beauty that he sees is available to other people and to me, too, i believe, although i might not be quite as refined aesthetically as he is; but i can appreciate the beauty of a flower. at the same time i see much more about the flower than he sees. i can imagine the cells in there, the complicated actions inside which also have a beauty. i mean it’s not just beauty at this dimension of one centimeter, there is also beauty at a smaller dimension, the inner structure. also the processes, the fact that the colors in the flower evolved in order to attract insects to pollinate it is interesting - it means that insects can see the color. it adds a question: does this aesthetic sense also exist in the lower forms? why is it aesthetic? all kinds of interesting questions which shows that a science knowledge only adds to the excitement and mystery and the awe of a flower. it only adds; i don’t understand how it subtracts..”

“Tell your son to stop trying to fill your head with science — for to fill your heart with love is enough. ”

“I'd hate to die twice. It's so boring.”

“The female mind is capable of understanding analytic geometry... The difficulty may just be that we have never yet discovered a way to communicate with the female mind. If it is done in the right way, you may be able to get something out of it.”

“Physics is to math what sex is to masturbation.”

“Philosophers say a great deal about what is absolutely necessary for science, and it is always, so far as one can see, rather naive, and probably wrong.”

“Philosophy of science is about as useful to scientists as ornithology is to birds.”

“I don't know what's the matter with people: they don't learn by understanding, they learn by some other way — by rote or something. Their knowledge is so fragile!”

“You say you are a nameless man. You are not to your wife and to your child. You will not long remain so to your immediate colleagues if you can answer their simple questions when they come into your office. You are not nameless to me. Do not remain nameless to yourself — it is too sad a way to be. Know your place in the world and evaluate yourself fairly, not in terms of the naïve ideals of your own youth, nor in terms of what you erroneously imagine your teacher's ideals are.”

“Poets say science takes away from the beauty of the stars - mere globs of gas atoms. I too can see the stars on a desert night, and feel them. But do I see less or more? The vastness of the heavens stretches my imagination - stuck on this carousel my little eye can catch one - million - year - old light. A vast pattern - of which I am a part... What is the pattern, or the meaning, or the why? It does not do harm to the mystery to know a little about it. For far more marvelous is the truth than any artists of the past imagined it. Why do the poets of the present not speak of it? What men are poets who can speak of Jupiter if he were a man, but if he is an immense spinning sphere of methane and ammonia must be silent?”

“People often think I'm a faker, but I'm usually honest, in a certain way--in such a way that often nobody believes me!”

“There are 10^11 stars in the galaxy. That used to be a huge number. But it's only a hundred billion. It's less than the national deficit! We used to call them astronomical numbers. Now we should call them economical numbers.”

“In physics the truth is rarely perfectly clear, and that is certainly universally the case in human affairs. Hence, what is not surrounded by uncertainty cannot be the truth.”