Feynman on Scientific Method.

situation now I'm going to discuss how we would look for a new law in general we look for new law by the following process first we get it then we come don't let that's what's really true then we compute the consequences of the guest to see what if this is right if this law that we guessed is right we see what it would imply and then we compare those computation results to nature or we say compared to experiment or experience compare it directly with observation to see if it if it works if it disagrees with experiment it's wrong in that simple statement is the key to science it doesn't make a difference how beautiful your guess is it doesn't make even as smart you are who made the get or what his name is if it disagrees with experiment draw a tourist toy it's therefore not unscientific to take a guess although many people who are not in science think it is for instance I had a conversation about flying saucers some years ago with lamely because I'm scientific I know all about flying saucers so I said I don't think there are flying saucers so the other my antagonist said is it impossible that they were flying closer can you prove it it's impossible you know I can't prove it's impossible it's just very unlikely that they say you are very unscientific if you can't prove it impossible then right how can you say it's likely that is unlike well that's the way that is scientific it is scientific only to say what's more likely and less likely and not to be proving all the time possible impossible to define what I mean I finally said to him listen I mean that for my knowledge of the world that I see around me I think that it is much more likely that the reports of flying saucers are the result of them known he rational characteristics of terrestrial intelligence rather than the unknown rational efforts of extraterrestrial intelligence it's just more likely that's and it's a good guess and we always tried to guess the most likely explanation keeping in the back of the mind the fact that if it doesn't work then we must discuss the other possibility there was for instance for awhile a phenomenon called superconductivity that still is the phenomenon which is that metals conduct electricity without resistance at low temperatures and it was not at first obvious that this was a consequence of the known laws with these particles but it turns out that it has been thought through caffeine up and it's seen in fact to be a consequence of known laws there are other phenomena such as extrasensory perception which cannot be explained by this known knowledge of physics here and it is interesting however that that phenomenon has not been well established and that we cannot guarantee that it's there so if it could be demonstrated of course that would prove that the physics is incomplete of therefore it's extremely interesting to physicists whether it's right or wrong and many many experiments exist which show it doesn't work the same goes for theological influences if they were true that the Stars could affect the day that it was good to go to the dentist then that there's an America we have that kind of astrology then it would be wrong the physics theory would be wrong because there's no mechanism by understandable and principle from these things that would make it golf and that's the reason that there's some skepticism among scientists with regard to those ideas now you see of course that with this method we can disprove any definite theory you have a definite theory a real guess from which you can clearly compute consequences which could be compared to experiment that in principle we can get rid of any theory we can always prove any definite theory wrong notice however we never prove it right suppose that you invent a good guess calculate the consequences to discover that big consequence that you calculate agrees with experiment the theory is then right no it is simply not food law because in the future there could be a wider range of experiments you could include a wider range of consequences and you may discover then that this thing is wrong that's why I laws like Newton's laws for the motion of planets less such a long time he guessed the law of gravitation calculate all the kinds of consequences for the solar system and so on compare them to experiment and it took several hundred years before the slight error of the motion of mercury was developed during all that time the theory had been failed to be true wrong and could be taken to be temporarily right but it can never be proved right because tomorrow's experiment may succeed in proving what you thought was right wrong so we never are right we can only be sure we're wrong however it's a rather remarkable that we can last so long I mean have some idea what your last so long I must also point out you that you cannot prove a vague theory wrong if the guest that you make is fully expressed rather bay and the method that you use for car figuring out the consequences is rather a little vague you're not sure I mean you say I think everything's because it's all due to Mughals and Mughals do this and not more or less so I can sort of explain how this work then you see that that theory is good because it can't be proved wrong if the process of computing the consequences is indefinite then with a little skill any experimental result can be made to look like an expected consequence you're probably familiar with out another fields for example a hates his mother the reason is of course because she didn't caress him or love him enough when he was a child actually if you investigate you find out that it's a matter of fact he did love him very much and everything was alright well then it's because she was overindulgent when he was so by having a vague theory it's possible to get either resolved not a cure for this one is the following it would be possible to say if it were possible to state ahead of time how much love is not enough and how much love is overindulgent exactly and then there would be a perfectly legitimate theory against which you can make tests it is usually said when this is pointed out how much love is and so on oh you're dealing with psychological matters the fees can't be defined so precisely yes but then you can't claim to know anything about it now I want to concentrate from now on because I'm a theoretical physicist and more the lighter with this end of the problem as to what goes on how do you make the guesses now as strictly as I said before not of any importance where the guess comes from it's only important that it should agree with experiment and that it should be definite as possible as definite as possible but you say then is very simple we've set up a machine a great computing machine which has a random wheel in it that makes the succession of guesses and each time it guesses hypothesis about how nature should work computer media view the consequences and makes a comparison to a list of experimental results that has it the other end in other words guessing is a dumb man's job actually it's quite the opposite and I will try to explain why the first problem is how to start you see our style thought with all the known principles but the principles that are all known are inconsistent with each other so something has to be removed so we get a lot of letters from people always getting letters from people who are insisting that we ought to make holes in our guesses as follows you make a hole to make room for a new guest somebody says to you know you oh people always say space is continuous but how do you know when you get to a small enough dimension that they really are enough points in between it isn't just a lot of dot separated by little distances or they say you know those quantum mechanical amplitude is you told me about they're so complicated I'm sorry what makes you think those are right maybe they aren't right I get a lot of letters with such content but I must say that such remarks are perfectly obvious and now well are perfectly clear to anybody who's working on this problem and it doesn't do any good to point this out the problem is not what might be wrong but what might be substituted precisely in place of it if you say first anything precise for example in the case of a continuous space suppose the precise proposition is that space really consists of a series of dots only in the space between them doesn't mean anything and the dots are in a cubic array then we can prove that immediately is wrong that doesn't work you see the problem is not to make to change or to say something might be wrong but they replace it by something and that is not so easy as soon as any real definite idea is substituted that becomes almost immediately apparent that it doesn't work secondly there's an infinite number of possibilities on these of these simple types it's something like this you're sitting working very hard you work for a long time trying to open a safe and some Joe comes along who hasn't doesn't know anything about what you're doing or anything except that you're trying to open to say because you know why don't you try the combination ten twenty thirty because you're busy you tried a lot of things maybe you're already fried ten twenty thirty maybe you know that the middle number is already thirty-two and not twenty maybe you know that as a matter of fact this is a five digit combination so these letters don't do any good and so please don't send me any letters trying to tell me the thing is going to work I don't I read them to make sure I haven't already thought of that but it takes too long to answer them because they're usually in the class try 10 20 30 [Music]

Channel: seabala

Views: 1,194,698

Rating: 4.9715004 out of 5

Keywords: Richard, Feynman, Physicist, science, pseudoscience, astrology

Id: EYPapE-3FRw

Length: 9min 59sec (599 seconds)

Published: Fri Feb 18 2011

Reddit Comments

[u/mac_question]

God I love him so much. "Surely You're Joking, Mr. Feynman" is a great read.

For that matter, his physics books are some of the most down-to-earth explanations I've ever seen.

[u/Whargod]

This clip needs to be posted any time someone says "it's just a theory" when arguing against science.

[u/DefaultPlayer]

I've watched a lot of videos with Feynman in them, and while I love his accent, his way of thinking, his passion... I am so jealous of his god damned handwriting. It's so damn neat.

[u/ThavinceGene]

Motherfucker just explained to me how I should formulate my senteces when I'm arguing with people who are acting smart by saying things like "how can you be sure of evolution" or whatever...

[u/computer_d]

Perfect.

Too often when I'm discussing space and stuff I get told that I have a closed mind because I refute the likely existence of God (ironic that only Christianity comes to their mind concerning religion) as I can't prove God does not exist. It is so fucking frustrating to have people who don't even read; they don't read the news, they don't read any books, they don't even take part in discussions, instead just recite opinions, so listening to Feynman break it down so succinctly brings a huge sense of relief to me.

[u/BetterDadThanVader]

I love watching any footage of him. As a teacher (and physicist), he is such an inspiration.

[u/Octosphere]

I love listening to him talk. His excitement just oozes out.

[u/WATTHEBALL]

I can watch him write on the chalkboard all day.

[u/Azthioth]

His cursive and penmanship on that black board is phenomenal.