Richard Feynman citáty (206 citátů, strana 6)

Richard Feynman: 206 citátů 193 lajků

Richard Feynman nejznámější citáty

„Fyzika je jako sex, může přinést praktické výsledky, ale to není důvod, proč to děláme.“

Richard Feynman

„Fyzika se má k matematice tak, jako se má sex k masturbaci.“

Richard Feynman

„Einstein byl obr. Měl hlavu v oblacích, ale nohama pořád stál pevně na zemi. My, kteří nejsme tak vysocí, si musíme vybrat.“

Richard Feynman

„Pro ty, kteří neznají matematiku, je složité dostat se k takovým pocitům jako je krása, nejhlubší krása přírody… Pokud se chcete něco dozvědět o přírodě, oceňovat přírodu, je nutné rozumět jazyku, kterým mluví.“

Richard Feynman

„Byli jsme vedeni k představě věcí nekonečně zázračnějších než představy básníků a snílků minulosti. Ukazuje to, že imaginace přírody je mnohem, mnohem větší než imaginace člověka. Například o kolik pozoruhodnější je pro nás to, že jsme připoutáni vlivem záhadné přitažlivosti k otáčející se kouli – polovina z nás vzhůru nohama – která si miliardy let pluje prostorem, než představa, že jsme neseni na hřbetu slona nadnášeného želvou plovoucí v bezedném moři.“

Richard Feynman

„Fyzikální zákony platí i tam, kam jsme se ještě nedívali.“

Richard Feynman

Zdroj: [Grygar, Jiří, Jiří Grygar, Vesmír, jaký je: současná kosmologie (téměř) pro každého, 1, Mladá fronta, Praha, 1997, 217, Kolumbus, 135, 12, 80-204-0637-9]

Richard Feynman: Zamilované citáty

„V galaxii je 1011 hvězd. Kdysi to bývalo opravdu velké číslo. Ale je to jenom 100 miliard, to je míň než schodek státního rozpočtu. Takovým číslům jsme říkali astronomická, teď bychom jim měli říkat čísla ekonomická.“

Richard Feynman

„Proč nám příroda dovoluje uhodnout z vlastností jedné části chování zbytku? Jde o nevědeckou otázku. Nevím jak na ni odpovědět jinak než zcela nevědecky. Myslím, že je to tím, že důležitou vlastností přírody je jednoduchost – a proto je velmi krásná.“

Richard Feynman

„Věda je dlouhou historií školení o tom, jak si přestat lhát do kapsy.“

Richard Feynman

„Jací jsou to lidé – básníci, kteří dokáží hovořit o Jupiterovi jako o člověku, a zmlknou, když jde o ohromnou rotující kouli metanu a čpavku?“

Richard Feynman

Richard Feynman citáty a výroky

„Každý člověk obdrží klíč od nebeské brány. Tentýž klíč však také odemyká bránu pekel.“

Richard Feynman

citace neznámého průvodce z Havaje

O pekle

„Fyzikové si rádi myslí, že stačí říci: Toto jsou výchozí podmínky, co se stane pak?“

Richard Feynman

„Kdyby nějaký Marťan (který nikdy nezemře, snad jen při nehodě) přišel na Zemi a viděl tento zvláštní druh bytostí – tyto lidi žijící asi sedmdesát nebo osmdesát let s vědomím, že přijde smrt – zdálo by se mu, že musí být nesmírně depresivní žít a vědět, že život je jen dočasný. My lidé nějak přijdeme na to, jak žít i přes tento problém: smějeme se, vtipkujeme, žijeme.“

Richard Feynman

O lidech , O smrti , O problémech , O životě

„Rozvoj vědy a pokrok poznání se stávají stále obtížnější. Na experimentování již nestačí zápalky a sláma.“

Richard Feynman

O poznání , O vědě

„Svého času se v novinách objevil článek, v němž se uvádělo, že teorii relativity rozumí pouze dvanáct lidí. Nevěřím, že tomu tak kdy bylo. Možná jí rozuměl jenom jeden člověk, autor dosud nezveřejněného objevu. Ale poté, co se ostatní vědci seznámili s jeho myšlenkami, většinou tuto teorii tím nebo oním způsobem pochopili, a jistě jich bylo víc než dvanáct. Na druhé straně si však myslím, že mohu klidně prohlásit, že kvantové teorii nerozumí nikdo.“

Richard Feynman

O lidech , O myšlenkách , O čase

„Navštěvoval jsem kurz o bakteriofázích, ve kterém jsme se dozvěděli, jak se bakteriofágy zkoumají (bakteriofág je virus, který obsahuje DNA a napadá bakterie). Hned na začátku jsem zjistil, že mám ušetřenou spoustu práce díky tomu, že znám trochu fyziku a matematiku. Věděl jsem, jak se chovají atomy v kapalinách, takže jsem neviděl nic záhadného v tom, jak funguje odstředivka. Znal jsem dost statistiky, abych rozuměl statistickým chybám při počítání flíčků v misce. Takže zatímco se všichni moji kolegové-biologové snažili pochopit tyhle „novinky“, já mohl věnovat čas biologii.“

Richard Feynman

Dílo, To nemyslíte vážně, pane Feynmane!

O matematice , O chybách , O čase

„Byli jsme vedeni k představě věcí nekonečně zázračnějších než představy básníků a snílků minulosti. ukazuje to, že imaginace přírody je mnohem, mnohem větší než imaginace člověka.“

Richard Feynman

O minulosti , O přírodě

„Když vědec nezná odpověď na problém, žije v nevědomosti. Když výsledek tuší, žije v nejistotě. A když má proklatě velkou jistotu o charakteru výsledku, ještě pořád ho hlodají nějaké pochybnosti. Zjistili jsme, že pro dosažení pokroku to má ohromný význam. Musíme uznat naši ignoranci a ponechat prostor pochybám. Vědecké poznatky jsou souborem tvrzení pronesených s různým stupněm jistoty – některá tvrzení jsou naprosto nejistá, některá skoro jistá, ale žádná nejsou jistá absolutně.“

Richard Feynman

O životě , O problémech , O pochybnosti

„Nechtěl bych umírat dvakrát. Je to tak nudné.“

Richard Feynman

poslední slova

„V počátcích všech vědeckých pozorování jsme při hledání rozumného vysvětlení jevů vystačili s pouhou intuicí, založenou opravdu jen na prosté zkušenosti s všedními objekty. Ale jak se snažíme vypracovat lepší popis naší zkušenosti, která začíná zahrnovat stále širší rozsah jevů, přestávají být naše vysvětlení jednoduchá a stávají se tím, co nazýváme zákony. Často se zdá, že jsou čím dál nerozumnější a stále více vzdálené od toho, co považujeme za zřejmé.“

Richard Feynman

O hledání , O vzdálenosti , O zákonech

„Podívejte se, podle toho, co vím o okolním světě, soudím, že je mnohem pravděpodobnější, že zprávy o létajících talířích pocházejí spíše ze známých iracionálních charakteristik myslí pozemšťanů, než z neznámých racionálních snah myslících bytostí z jiných planet.“

Richard Feynman

O snaze , O světě

„Věda je hodně podobná sexu. Někdy z ní vzejde něco užitečného, ale to není ten jediný důvod, proč ji děláme.“

Richard Feynman

Zdroj: [Pincott, Jena, Mají muži radši blondýnky?: láska, sex a přitažlivost, Nicolle Knapová, Dobrovský s.r.o., Praha, 2017, 296, Knihy Omega, Úvod, 9, 978-80-7390-460-9]

O sexu , O vědě

„Ty knihy prostě nestály za nic. Byly špatné, byly odfláknuté. Snažily se být exaktní, ale používaly příkladů, které byly skoro správné, ale vždycky na nich byly nějaké mouchy. Definice nebyly přesné. Všechno bylo trochu mnohoznačné - autoři nebyli dost chytří na to, aby chápali, co „přesnost“ znamená. Jen ji předstírali. Vykládali něco, čemu nerozuměli a co bylo v dané chvíli dítěti úplně k ničemu. Psal to někdo, kdo pořádně nevěděl, o čem mluví, takže to bylo vždycky trochu špatně! A jak dobře učit podle knížek napsanými lidmi, kteří pořádně nerozumějí tomu, o čem mluví, to nedovedu pochopit. Nevím proč, ale ty knížky byly mizerné; MIZERNÉ PO VŠECH STRÁNKÁCH! Něco vypadalo na první pohled dobře, a pak mě z toho jímal děs. A takhle to vypadalo se všemi těmi knihami. Vykládaly o věcech, které byly neužitečné, zmatené a matoucí, mnohoznačné a částečně nesprávné.“

Richard Feynman

O dětech , O knihách

Richard Feynman

Psal to někdo, kdo pořádně nevěděl, o čem mluví, takže to bylo vždycky trochu špatně! A jak dobře učit podle knížek napsanými lidmi, kteří pořádně nerozumějí tomu, o čem mluví, to nedovedu pochopit. Nevím proč, ale ty knížky byly mizerné; MIZERNÉ PO VŠECH STRÁNKÁCH! Něco vypadalo na první pohled dobře, a pak mě z toho jímal děs. A takhle to vypadalo se všemi těmi knihami. Vykládaly o věcech, které byly neužitečné, zmatené a matoucí, mnohoznačné a částečně nesprávné.
Dílo, To nemyslíte vážně, pane Feynmane!

O dětech , O knihách

„Naše svoboda pochybovat se zrodila z boje proti autoritám v počátcích vědy. Byl to velmi hluboký a silný boj: dovolte nám klást otázky, pochybovat... a nebýt si jistí. Myslím, že je důležité, abychom na tento boj nezapomněli - i když tím možná ztratíme to, co už jsme získali.“

Richard Feynman

O boji , O svobodě , O vědě

Richard Feynman: Citáty anglicky

“The same equations have the same solutions”

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Richard Feynman

volume II; lecture 12, "Electrostatic Analogs"; p. 12-1
The Feynman Lectures on Physics (1964)

“So in order to understand the physics one must always have a neat balance and contain in his head all of the various propositions and their interelationships because the laws often extend beyond the range of their deductions. This will only have no importance when all the laws are known.”

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Richard Feynman kniha The Character of Physical Law

Zdroj: The Character of Physical Law (1965), chapter 2, “ The Relation of Mathematics to Physics http://www.youtube.com/watch?v=M9ZYEb0Vf8U”

“So, ultimately, in order to understand nature it may be necessary to have a deeper understanding of mathematical relationships. But the real reason is that the subject is enjoyable, and although we humans cut nature up in different ways, and we have different courses in different departments, such compartmentalization is really artificial, and we should take our intellectual pleasures where we find them.”

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Richard Feynman

volume I; lecture 22, "Algebra"; section 22-1, "Addition and multiplication"; p. 22-1
The Feynman Lectures on Physics (1964)

“Looking back at the worst times, it always seems that they were times in which there were people who believed with absolute faith and absolute dogmatism in something. And they were so serious in this matter that they insisted that the rest of the world agree with them. And then they would do things that were directly inconsistent with their own beliefs in order to maintain that what they said was true.”

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Richard Feynman kniha The Meaning of It All

lecture II: "The Uncertainty of Values"
The Meaning of It All (1999)

“Suppose two politicians are running for president, and one goes through the farm section and is asked, "What are you going to do about the farm question?" And he knows right away - bang, bang, bang. Now he goes to the next campaigner who comes through. "What are you going to do on the farm problem?" "Well, I don't know. I used to be a general, and I don't know anything about farming. But it seems to me it must be a very difficult problem, because for twelve, fifteen, twenty years people have been struggling with it, and people say that they know how to solve the farm problem. And it must be a hard problem. So the way I intend to solve the farm problem is to gather around me a lot of people who know something about it, to look at all the experience that we have had with this problem before, to take a certain amount of time at it, and then to come to some conclusion in a reasonable way about it. Now, I can't tell you ahead of time what solution, but I can give you some of the principles I'll try to use - not to make things difficult for individual farmers, if there are any special problems we will have to have some way to take care of them," etc., etc., etc.
Now such a man would never get anywhere in this country, I think. It's never been tried, anyway. This is in the attitude of 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 fact; 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.”

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Richard Feynman kniha The Meaning of It All

lecture III: "This Unscientific Age"
The Meaning of It All (1999)

“If the professors of English will complain to me that the students who come to the universities, after all those years of study, still cannot spell "friend," I say to them that something's the matter with the way you spell friend.”

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Richard Feynman kniha The Meaning of It All

lecture III: "This Unscientific Age"
The Meaning of It All (1999)

“…I don't believe in the idea that there are a few peculiar people capable of understanding math and the rest of the world is normal. Math is a human discovery, and it's no more complicated than humans can understand. I had a calculus book once that said, "What one fool can do, another fool can." What we've been able to work out about nature may look abstract and threatening to someone who hasn't studied it, but it was fools who did it, and in the next generation, all the fools will understand it. There's a tendency to pomposity in all this, to make it all deep and profound…”

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Richard Feynman kniha The Pleasure of Finding Things Out

From Omni interview, "The Smartest Man in the World" (1979) or from the book p. 194.
The Pleasure of Finding Things Out (1999)

“…In that same period there was Newton, there was Harvey studying the circulation of the blood, there were people with methods of analysis by which progress was being made! You can take every one of Spinoza's propositions and take the contrary propositions and look at the world--and you can't tell which is right. Sure, people were awed because he had the courage to take on these great questions, but it doesn't do any good to have the courage if you can't get anywhere with the question…”

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Richard Feynman kniha The Pleasure of Finding Things Out

From Omni interview, "The Smartest Man in the World" (1979) or from the book p. 195.
The Pleasure of Finding Things Out (1999)

“I had too much stuff. My machines came from too far away.”

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Richard Feynman

Reflecting on the failure of his presentation at the "Pocono Conference" of 30 March - 1 April 1948.
interview with Sylvan S. Schweber, 13 November 1984, published in QED and the Men Who Made It: Dyson, Feynman, Schwinger, and Tomonaga (1994) by Silvan S. Schweber, p. 436

“A very great deal more truth can become known than can be proven.”

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Richard Feynman

"The Development of the Space-Time View of Quantum Electrodynamics," Nobel Lecture http://nobelprize.org/physics/laureates/1965/feynman-lecture.html (11 December 1965)

“And this is medicine?”

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Richard Feynman

Comment to psychiatrist who examines Feynman and states he (the psychiatrist) has studied medicine.
Part 3: "Feynman, The Bomb, and the Military", "Uncle Sam Doesn't Need <u>You</u>", p. 159
Surely You're Joking, Mr. Feynman! (1985)

“This dying is boring.”

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Richard Feynman

last words (15 February 1988), recalled by sister Joan Feynman, in Christopher Sykes, editor, No Ordinary Genius: The Illustrated Richard Feynman (1994), p. 254

“What I cannot create, I do not understand.Know how to solve every problem that has been solved.”

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Richard Feynman

on his blackboard at the time of death in February 1988; from a photo in the Caltech archives http://archives.caltech.edu/pictures/1.10-29.jpg

“Of course if we make good things, it is not only to the credit of science; it is also to the credit of the moral choice which led us to good work. Scientific knowledge is an enabling power to do either good or bad — but it does not carry instructions on how to use it. Such power has evident value — even though the power may be negated by what one does with it.I learned a way of expressing this common human problem on a trip to Honolulu. In a Buddhist temple there, the man in charge explained a little bit about the Buddhist religion for tourists, and then ended his talk by telling them he had something to say to them that they would never forget — and I have never forgotten it. It was a proverb of the Buddhist religion:To every man is given the key to the gates of heaven; the same key opens the gates of hell.What then, is the value of the key to heaven? It is true that if we lack clear instructions that enable us to determine which is the gate to heaven and which the gate to hell, the key may be a dangerous object to use.But the key obviously has value: how can we enter heaven without it?”

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Richard Feynman

The Value of Science (1955)

“The real problem in speech is not precise language. The problem is clear language. The desire is to have the idea clearly communicated to the other person. It is only necessary to be precise when there is some doubt as to the meaning of a phrase, and then the precision should be put in the place where the doubt exists. It is really quite impossible to say anything with absolute precision, unless that thing is so abstracted from the real world as to not represent any real thing.Pure mathematics is just such an abstraction from the real world, and pure mathematics does have a special precise language for dealing with its own special and technical subjects. But this precise language is not precise in any sense if you deal with real objects of the world, and it is only pedantic and quite confusing to use it unless there are some special subtleties which have to be carefully distinguished.”

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Richard Feynman

" New Textbooks for the "New" Mathematics http://calteches.library.caltech.edu/2362/1/feynman.pdf", Engineering and Science volume 28, number 6 (March 1965) p. 9-15 at p. 14
Paraphrased as "Precise language is not the problem. Clear language is the problem."

“We absolutely must leave room for doubt or there is no progress and no learning. There is no learning without having to pose a question. And a question requires doubt. People search for certainty. But there is no certainty. People are terrified — how can you live and not know?”

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Richard Feynman kniha The Pleasure of Finding Things Out

It is not odd at all. You only think you know, as a matter of fact. And most of your actions are based on incomplete knowledge and you really don't know what it is all about, or what the purpose of the world is, or know a great deal of other things. It is possible to live and not know.
from lecture "What is and What Should be the Role of Scientific Culture in Modern Society", given at the Galileo Symposium in Italy (1964)
The Pleasure of Finding Things Out (1999)

“This is not a new idea; this is the idea of the age of reason. This is the philosophy that guided the men who 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. This method was a result of the fact that science was already showing itself to be a successful venture at the end of the eighteenth century. Even then it was clear to socially minded people that the openness of possibilities was an opportunity, and that doubt and discussion were essential to progress into the unknown. If we want to solve a problem that we have never solved before, we must leave the door to the unknown ajar.”

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Richard Feynman

The Value of Science (1955)

“But, in admitting this, we have probably found the open channel.”

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Richard Feynman

The Value of Science (1955)

“The philosophy of science is as useful to scientists as ornithology is to birds.”

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Richard Feynman

Attributed to Feynman, many times, by the British historian of science Brian Cox.
Disputed and/or attributed

“I, therefore, did learn a lesson: The female mind is capable of understanding analytic geometry. Those people who have for years been insisting (in the face of all obvious evidence to the contrary) that the male and female are equally capable of rational thought may have something. 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.”

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Richard Feynman

address " What is Science? http://www.fotuva.org/feynman/what_is_science.html", presented at the fifteenth annual meeting of the National Science Teachers Association, in New York City (1966), published in The Physics Teacher, volume 7, issue 6 (1969), p. 313-320

“Do not keep saying to yourself, if you can possibly avoid it, "But how can it be like that?"”

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Richard Feynman kniha The Character of Physical Law

because you will get "down the drain", into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that.
Concerning the apparent absurdities of quantum behavior.
Zdroj: The Character of Physical Law (1965), chapter 6, “Probability and Uncertainty — the Quantum Mechanical View of Nature,” p. 129

“What do we mean by “understanding” something? We can imagine that this complicated array of moving things which constitutes “the world” is something like a great chess game being played by the gods, and we are observers of the game. We do not know what the rules of the game are; all we are allowed to do is to watch the playing. Of course, if we watch long enough, we may eventually catch on to a few of the rules. The rules of the game are what we mean by fundamental physics.”

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Richard Feynman

Even if we knew every rule, however, we might not be able to understand why a particular move is made in the game, merely because it is too complicated and our minds are limited. If you play chess you must know that it is easy to learn all the rules, and yet it is often very hard to select the best move or to understand why a player moves as he does. So it is in nature, only much more so.
volume I; lecture 2, "Basic Physics"; section 2-1, "Introduction"; p. 2-1
The Feynman Lectures on Physics (1964)

“Western civilization, it seems to me, stands by two great heritages. One is the scientific spirit of adventure — the adventure into the unknown, an unknown which must be recognized as being unknown in order to be explored; the demand that the unanswerable mysteries of the universe remain unanswered; the attitude that all is uncertain; to summarize it — the humility of the intellect. The other great heritage is Christian ethics — the basis of action on love, the brotherhood of all men, the value of the individual — the humility of the spirit.
These two heritages are logically, thoroughly consistent. But logic is not all; one needs one's heart to follow an idea. If people are going back to religion, what are they going back to? Is the modern church a place to give comfort to a man who doubts God — more, one who disbelieves in God? Is the modern church a place to give comfort and encouragement to the value of such doubts? So far, have we not drawn strength and comfort to maintain the one or the other of these consistent heritages in a way which attacks the values of the other? Is this unavoidable? How can we draw inspiration to support these two pillars of western civilization so that they may stand together in full vigor, mutually unafraid? Is this not the central problem of our time?”

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Richard Feynman

remarks (2 May 1956) at a Caltech YMCA lunch forum http://calteches.library.caltech.edu/49/2/Religion.htm

“It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesn't get confined, permanently blocked, as it has so many times before in various periods in the history of man.”

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Richard Feynman kniha The Meaning of It All

lecture II: "The Uncertainty of Values"
The Meaning of It All (1999)

“I can live with doubt, and uncertainty, and not knowing. I think it's much more interesting to live not knowing than to have answers which might be wrong. I have approximate answers, and possible beliefs, and different degrees of certainty about different things, but I'm not absolutely sure of anything. There are many things I don't know anything about, such as whether it means anything to ask "Why are we here?"”

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Richard Feynman kniha The Pleasure of Finding Things Out

I might think about it a little bit, and if I can't figure it out then I go on to something else. But I don't have to know an answer. I don't feel frightened by not knowing things, by being lost in the mysterious universe without having any purpose — which is the way it really is, as far as I can tell. Possibly. It doesn't frighten me.
Zdroj: No Ordinary Genius (1994), p. 239, from interview in "The Pleasure of Finding Things Out" (1981): video http://www.youtube.com/watch?v=NEwUwWh5Xs4&t=48m10s

“Poets say science takes away from the beauty of the stars — mere globs of gas atoms. Nothing is "mere."”

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Richard Feynman

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! 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?
volume I; lecture 3, "The Relation of Physics to Other Sciences"; section 3-4, "Astronomy"; p. 3-6
The Feynman Lectures on Physics (1964)

“The only way to have real success in science, the field I'm familiar with, is to describe the evidence very carefully without regard to the way you feel it should be. If you have a theory, you must try to explain what's good and what's bad about it equally. In science, you learn a kind of standard integrity and honesty.”

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Richard Feynman

“I think it's much more interesting to live not knowing than to have answers which might be wrong… I don't feel frightened not knowing things, by being lost in a mysterious universe without any purpose, which is the way it really is as far as I can tell.”

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Richard Feynman

Zdroj: Curious Character

“If you want to master something, teach it. Teaching is a powerful tool for learning.”

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Richard Feynman

“…study hard what interests you the most in the most undisciplined, irreverent and original manner possible.”

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Richard Feynman

excerpt from letter to J. M. Szabados (30 November 1965), quoted in "Perfectly Reasonable Deviations from the Beaten Track The Letters of Richard P. Feynman" (2005) by Michelle Feynman and Carl Feynman, p. 206