Jed Buchwald: Isaac Newton and the Philosophy of Science | Lex Fridman Podcast #214

1. 0:00 – 0:31

   Introduction

   1. LFLex Fridman0:00

      The following is a conversation with Jed Buchwald, a professor of history and a philosopher of science at Caltech, interested especially in the development of scientific concepts and the instruments used to create and explore new effects and ideas in science. To support this podcast, please check out our sponsors in the description. This is the Lex Fridman Podcast, and here is my conversation with Jed Buchwald.

2. 0:31 – 16:44

   How does science progress?

   1. LFLex Fridman0:31

      Does science progress via paradigm shifts and, uh, revolutions, as philosopher Thomas Kuhn said, or does it progress gradually? What do you think?

   2. JBJed Buchwald0:41

      Well, I got into this field 'cause I was Tom Kuhn's research assistant 50 years ago-

   3. LFLex Fridman0:47

      Wow.

   4. JBJed Buchwald0:47

      ... 52 years ago.

   5. LFLex Fridman0:49

      Really?

   6. JBJed Buchwald0:49

      He pulled me into it out of physics instead, so I know his work pretty well. And in the years when I was at MIT running an institute, he was then in the philosophy department. He used to come over all the time to the talks we held and so on. So what would I say about that? He, of course, developed his ideas a lot over the years.

   7. LFLex Fridman1:11

      Yes.

   8. JBJed Buchwald1:11

      The thing that he's famous for, The (laughs) H- (clears throat) Structure of Scientific Revolutions, came out in '62. And, um, as you just said, it offered, um, an outline for what he called a paradigmatic structure, namely the notion that (clears throat) you have to look at what scientists do is forming a community of investigators, and that they're trying to solve various puzzles, as he would put it, that crop up. Figuring out how this works, how that works, and so on. And of course, they don't do it out of the blue. They do it within a certain framework. The framework can be pretty vague. He called it a paradigm. And his notion was that eventually, they run into troubles or what he called anomalies that kind of cracks things. Somebody new comes along with a different way of doing it, et cetera. Do I think things work that way? No, not really. Tom and I used to have lengthy discussions about that over the years. Um, w- I do think there is a common structure that formulates both theoretical and experimental practices.

   9. LFLex Fridman2:24

      Mm-hmm.

   10. JBJed Buchwald2:24

       And historians nowadays of science like to refer to scientific work as what scientists practice. It's, uh, almost craftsman-like. They can usually adapt in various ways. Uh, and I can give you all kinds of examples of that. I once wrote a book on the origins of wave theory of light, and that is one of the paradigmatic examples that Tom used, only it didn't work that way exactly, because he thought that what happened was that the, um, wave theory ran into trouble with a certain phenomenon which it couldn't crack.

   11. LFLex Fridman3:05

       Mm-hmm.

   12. JBJed Buchwald3:05

       Well, it turned out that, in fact, historically, that phenomenon was actually, um, not relevant later on to the wave theory. And when the wave theory came in, uh, the alternative to it which had prevailed, which was Newton's views, light as particles, that, it seemed, couldn't explain what the wave theory could explain. Again, not true. Not true. Uh, much more complex than that, the wave theory offered the opportunity to deploy novel experimental and mathematical structures which gave younger scientists, mathematicians and others, the opportunity to effect, manufacture, make new sorts of devices. It's not that the alternative couldn't sort of explain these things, but it never was able to generate them de novo, as novelties. In other words, if you think of it as something scientists want to progress in the sense of finding new stuff to solve-

   13. LFLex Fridman4:11

       Mm-hmm.

   14. JBJed Buchwald4:12

       ... then I think what often happens is, is that it's not so much that the prevailing view can't crack something as that it doesn't give you the opportunity to do new stuff.

   15. LFLex Fridman4:23

       When you say new stuff, are we referring to experimental science here or new stuff in the space of, uh, new theories?

   16. JBJed Buchwald4:29

       Could be both. Could be both, actually.

   17. LFLex Fridman4:33

       So how does that... Can you maybe elaborate a little bit on the story of the wave, your view of light?

   18. JBJed Buchwald4:36

       Sure. The prevailing view of light, at least in France where the wave theory really first took off, although it had been introduced in England by Thomas Young, the prevailing theory dates back to Newton that light is a stream of particles and that refraction and reflection involve sort of repulsive and attractive forces that deflect and bend the paths of these particles. (clears throat) Newton was not able successfully to deal with the phenomenon of what happens when light goes past a knife's edge or a sharp edge, what we now call diffraction. Now, he had cooked up something about it that no mathematical structure could be applied. Um, Thomas Young first, but really this guy named Augustin Fresnel in France deployed, in Fresnel's case, rather advanced calculus forms of mathematics which enabled computations to be done and observations to be melded with these computations in a way that you could not do or see how to do with Newton. Did that mean that the Newtonian explanation of what goes on in diffraction fails? Not really. You can, you can actually, um, make it work, but you can't generate anything new out of it, whereas using the mathematics of wave optics in respect to a particular phenomenon called polarization...Which ironically was discovered by partisans of Newton's way of doing things, you were able to generate devices which reflect light in crystals, do various things that the Newtonian way could accommodate only after the fact. They couldn't generate it from the beginning. And so if you want to be, uh, somebody who is working a novel vein, which increasingly becomes the case with, uh, people who become what we now call physicists in the 1820s, 30s, and 40s, in particular, then that's the direction you're gonna go. But there were holdouts until the 1850s.

   19. LFLex Fridman6:55

       I want to try to elaborate on the nature of the disagreement you have with Thomas Kuhn. So, do you still believe in paradigm shifts? Do, do, do you still see that there is ideas that really have a transformational effect on science, you just, the nature of the disagreement has to do with how those paradigm shifts come to be?

   20. JBJed Buchwald7:15

       How they come to be and how they change. I certainly think they exist. How strong they may be at any given time is maybe not quite as powerful as Tom thought in general. Although towards the end of his life, he was beginning to develop, uh, different, um, modifications of his original way of thinking. Uh, but I don't think that the changes happened quite so, um, neatly, if you will, in reaction to, um, novel experimental observations. They get much more complex than that.

   21. LFLex Fridman7:53

       In terms of neatness, how much of science progresses by individual lone geniuses and how much by the messy collaboration of competing and, um, cooperating humans?

   22. JBJed Buchwald8:12

       I don't think you can cut that with a knife to say it's this percent and that percent. It's almost always the case that there are one or two or maybe three individuals who are sort of central to what goes on when things begin to shift. Are they inevitably and solely responsible for what then begins to happen, um, in a major way? I think not. Uh, it depends. You can go f- very far back with this, uh, (clears throat) even into antiquity to see what goes on. Um, the locus, the major locus we always talk about from the beginning is, if you're talking about Galileo's work on motion, for example, uh, were there ways of accommodating it that others could adapt to without buying into the whole scheme? Yes. Um, did it eventually evolve and start convincing people because you could also do other things with it that you couldn't otherwise do? Also yes. Let me give you an example. The great French mathematician philosopher, Descartes, who, uh, was a mechanical philosopher, he believed the world was matter in motion, he never thought much of what Galileo had done in respect to motion, because he thought, "Well, at best, it's some sort of approximative scheme or something like that." But one of his, um, initial, uh, I wouldn't call him a disciple, but follower who then broke with him in a number of ways, was a man named Christiaan Huygens, who was, along with Newton, one of the two greatest scientists of the 17th century. Huygens is older than Newton. And Huygens nicely deployed Galilean relationships in respect to motion to develop all sorts of things, including the first pendulum-governed clock, and even figured out how to build one which is, keeps perfect time, except it didn't work.

   23. LFLex Fridman10:24

       (laughs)

   24. JBJed Buchwald10:24

       But he had the mathematical structure for it.

   25. LFLex Fridman10:27

       How well known is Huygens?

   26. JBJed Buchwald10:28

       Oh, very well known.

   27. LFLex Fridman10:29

       Should I be, should I know him well?

   28. JBJed Buchwald10:31

       Yes, you should.

   29. LFLex Fridman10:32

       Interesting.

   30. JBJed Buchwald10:33

       (laughs)
3. 16:44 – 28:37

   Theory of Everything

   1. JBJed Buchwald16:44

      century.

   2. LFLex Fridman16:45

      So maybe we just speak to that. You're referring to a hope, a dream, a reality of coming up with the theory of everything that, that explains everything. So there's a very specific thing that that currently means in physics, is the unification of the laws of physics. But I'm sure in antiquity or before, it meant maybe something else, or was it always about physics? 'Cause I... I mean, I think as you've kind of implied, in physics, there's a sense once you get to the theory of everything, you've understood everything. But there's a very deep sense in which you've actually understood not very much at all. You've understood at that particular level how things work, but you don't understand how the abstractions on top of abstractions form, all the way to the chemistry, to the human mind, and the human societies, and all those kinds of things. So, uh, may- maybe you can speak to the theory of everything and its history and, and comment on what the heck does that even mean-

   3. JBJed Buchwald17:42

      (laughs)

   4. LFLex Fridman17:42

      ... a theory of everything.

   5. JBJed Buchwald17:43

      Well, I don't think you can go back that far with something like that. Maybe to the, at best, to the 17th century. If you go back all the way in antiquity, there are, of course, discussions about the nature of the world.

   6. LFLex Fridman17:58

      Right.

   7. JBJed Buchwald17:59

      But first of all, you have to, um, you have to recognize that the manipulative character of physics and chemistry, the probing of... Uh, let me put it this way. We assume and have assumed for a long time, I'll come back to when in a moment, that if I take...... a, a little device which is really complicatedly made out of all kinds of things, and I put a piece of some material in it, and I monkey around with it and do all kinds of unnatural things to it, things that wouldn't happen naturally, and I find out how it behaves and whatnot, and then I try and make an argument about how that really applies even in the natural world without any artificial structures and so on, that's not a belief that was widely held, uh, by pretty much anyone until sometime maybe in the 1500s. And when it was first held, it was held by people we now call alchemists.

   8. LFLex Fridman19:09

      So alchemy was the first, the early days of the theory of everything, of a dream of a theory of everything.

   9. JBJed Buchwald19:14

      I would put it a little differently. I think it's more along the way a dream that by probing nature in artificially constructed ways, we can find out what's going on deep down there.

   10. LFLex Fridman19:32

       So that was, that's distinct from science being an observing thing, where you observe nature and you study nature. You're talking about probing, like, messing with nature to understand it.

   11. JBJed Buchwald19:45

       Indeed, I am. And, but that, of course, is the very essence of experimental science.

   12. LFLex Fridman19:50

       Yeah.

   13. JBJed Buchwald19:51

       Um, you have to, um, you have to manipulate nature to find out things about it, and then you have to convince, um, others that you haven't so manipulated it that what you've done is to produce what amounts to fake artifactual behavior that doesn't really hold purely naturally.

   14. LFLex Fridman20:14

       So where are we today, in your sense, to jump around a little bit, with the theory of everything? Maybe a, a, a quick kind of, uh, sense you have about the journey in the world of physics that we're taking towards the theory of everything.

   15. JBJed Buchwald20:31

       Well, I'm, of course, not a practicing physicist. I mean, I was trained in physics at Princeton a long time ago.

   16. LFLex Fridman20:38

       Until Thomas Kuhn stole you away.

   17. JBJed Buchwald20:41

       More or less. I was taking graduate courses in those days in general relativity. I was an undergraduate, but I moved up and then I took a course with him and-

   18. LFLex Fridman20:51

       Well, you made the mistake of, uh, being compelled by charismatic philosophers and, uh, never looked back.

   19. JBJed Buchwald20:57

       (laughs) I suppose so, in a way.

   20. LFLex Fridman21:00

       Okay.

   21. JBJed Buchwald21:00

       And, um, from what I understand, talking especially to my friends at Caltech, uh, like Kip Thorne and others, the, um, the fundamental notion is that actually the laws that even at the deepest level we can sort of divine and work with in the universe that we inhabit are perhaps quite unique to this particular universe as it formed at the Big Bang.

   22. LFLex Fridman21:33

       Mm-hmm.

   23. JBJed Buchwald21:34

       The question is, how deep does it go? If you are very mathematically inclined, the prevailing notion for, uh, several decades now has been what's called string theory.

   24. LFLex Fridman21:47

       Mm-hmm.

   25. JBJed Buchwald21:48

       Um, but that has not been able to figure a way to generate probative experimental evidence, although it's pretty good apparently at accommodating things. And then the question is, you know, what's before the Big Bang? Or, actually, the word "before" doesn't mean anything given the nature of time, but, but, um, why the, why do we have the laws that prevail in our universe? Well, there is a notion that those laws prevail in our universe because if they didn't, we wouldn't be here. (laughs)

   26. LFLex Fridman22:30

       (laughs) That's a bit of a cyclical, but, uh-

   27. JBJed Buchwald22:32

       (laughs)

   28. LFLex Fridman22:32

       ... nevertheless a compelling definition. And there's all kinds of things like the, it seems like the unification of those laws could be discovered by looking inside of a black hole, because you get both the general relativity and the quantum mechanics, quantum field theory in there. Uh, experimentally, of course, there's a lot of interesting ideas. We can't really look close to the Big Bang. We can't look that far back. Uh, there's, Caltech and MIT with LIGO looking at gravitational waves, perhaps allows us to march backwards and so on. Yeah, it's a really exciting space. And there's, of course, the theory of everything, like with a lot of things in science, captivates the dreams of those who are perhaps completely outside of science. It's the dream of discovering the key to how the, you know, the nature of how everything works. And that feels, uh, that feels deeply human. That's perhaps the thing, the, the basic elements of what makes up s- a, a scientist in the end is that curiosity, that longing to understand. Let me ask, uh, you mentioned a disagreement with Weinberg on, uh, reality. Uh, could you elaborate a little bit?

   29. JBJed Buchwald23:46

       Well, I, obviously, I don't disagree with Steve Weinberg on physics itself. I wouldn't know enough to even begin to do that. Uh, and clearly, you know, he's one of the founders of the standard model and so on, and it works, um, to a level of accuracy that no physical theory has ever worked at before. I suppose the question, in my mind, is something that, um, in one way could go back to the philosopher Immanuel Kant in the 18th century, namely, can we really ever convince ourselves that we have...... come to grips with something that is not in itself knowable to us by our senses, or even, except in the most remote way through the complex instruments that we make, as to what it is that underlies everything? Can we corral it with mathematics and experimental structures? Yes. Uh, do I think that a particular way of corralling nature will inevitably play itself out? I don't know. It always has. I'll put it to you that way. Um...

   30. LFLex Fridman25:08

       So the basic question is, can we know reality? Is that the, the, the Kant question, is that the Weinberg, uh, question? We humans-
4. 28:37 – 32:12

   Consciousness

   1. LFLex Fridman28:37

      outside of the reach of science? Can you maybe, as an example, talk about consciousness? I'm asking for a friend. Trying to figure this thing out.

   2. JBJed Buchwald28:50

      Well, boy, I mean, uh, I, I, uh, I read a fair bit about that, but I certainly don't, can't really say much about it. Um, I'm a materialist in the deepest sense of the term. I don't think there is anything out there except material structures which interact in various ways. Do I think, for example, that this bottle of water is conscious? No, I do not. Although, how would I know? I can't talk to it.

   3. LFLex Fridman29:24

      Yeah.

   4. JBJed Buchwald29:25

      But, so what do-

   5. LFLex Fridman29:26

      It's a hypothesis you have. It's an opinion, an educated opinion that may be very wrong.

   6. JBJed Buchwald29:31

      Well, I know that you're conscious because I can interact directly with you.

   7. LFLex Fridman29:35

      But am I?

   8. JBJed Buchwald29:36

      Well, unless you're a figment of my imagination, of course.

   9. LFLex Fridman29:39

      No, or, or I'm a, a robot that's able to generate the illusion, uh, the-

   10. JBJed Buchwald29:43

       Yes.

   11. LFLex Fridman29:44

       ... the illusion of consciousness effectively enough to facilitate a good conversation, 'cause we humans do want to pretend that we're talking to other conscious beings because that's how we respect them. If it's not conscious, we don't respect them. We're not good at talking to robots or whatever.

   12. JBJed Buchwald29:57

       That's true. Of course we generalize from our own inner sense-

   13. LFLex Fridman30:00

       Yeah.

   14. JBJed Buchwald30:00

       ... which is the kind of thing Descartes said-

   15. LFLex Fridman30:02

       Yes.

   16. JBJed Buchwald30:03

       ... uh, from the beginning, and we generalize from that. But, I do think that, um, consciousness must be something, whatever it is, that occurs as a result of some particular organizational structure of, um, uh, material elements.

   17. LFLex Fridman30:22

       Does materialism mean that it's all within a, within the reach of science?

   18. JBJed Buchwald30:28

       My sense would be that especially as, uh, neuroscience, um, progresses more and more, and at Caltech, we just built a whole neuroscience, um, arena and so on, and as more knowledge is gained about the ways in which animals, when they behave, what patterns show up at various parts of the brain and nervous system, and perhaps extending it to humans eventually as well, we'll get more of a handle on what brain activity is associated with, uh, experiences that we have as humans. Can we move from the brain activity to the experiences, uh, in terms of our per- No. You can't. Perception is perception.

   19. LFLex Fridman31:25

       That's a hypothesis once again. Maybe, maybe the, maybe consciousness is just one of the laws of physics that's yet to be discovered. Maybe it permeates all matter. Maybe it's... Uh, maybe it's as simple as trying to plug it in and, um, plug into th- the ability to generate and control that kind of law of physics that would crack open where we would understand that the wa- that the bottled water is in fact conscious, just much less conscious than us humans, and then we would be able to then generate, uh, beings that are more conscious.

   20. JBJed Buchwald32:02

       Well, that'll be unfortunate. I'd have to stop drinking the water after that.

   21. LFLex Fridman32:05

       (laughs)

   22. JBJed Buchwald32:05

       So. (laughs)

   23. LFLex Fridman32:06

       Every time you take a j- take a sip, there's a little bit of a s- suffering going on.

   24. JBJed Buchwald32:11

       Right.

5. 32:12 – 39:57

   Most Beautiful Moments in Science

   1. JBJed Buchwald32:12

   2. LFLex Fridman32:12

      What to you is the most interesting, beautiful moments in the history of science? What stands out?

   3. JBJed Buchwald32:18

      Uh.

   4. LFLex Fridman32:19

      And then we can pull at that thread.

   5. JBJed Buchwald32:21

      (laughs) Right. Well, I like to think of events that have a major impact and involve both beautiful, uh, conceptual, mathematical, if we're talking physical structures work, and are associated as well with probing experimental situations. So, um, among my favorites is one of the most famous which was, uh, the young Isaac Newton's work with the colors produced when you pass sunlight through a prism. And why do I like that? Um, it's not profoundly mathematical in one sense, doesn't need it initially. It needs the following though, which begins to show you, I think, a little bit about what gets involved when you've got a smart individual who's trying to monkey around with stuff and finds new things about it. Um, first let me say that the notion, the prevailing notion going back to antiquity was that, um, colors are produced in a sense by modifying or tinting white light.

   6. LFLex Fridman33:34

      Mm.

   7. JBJed Buchwald33:34

      That they're modifications of white light. In other words, the colors are not in the sunlight in any way.

   8. LFLex Fridman33:41

      Mm-hmm.

   9. JBJed Buchwald33:42

      Okay? Now, what Newton did, following experiments done by Descartes before him who came to very different conclusions, he took a prism. You might ask, where do you get prisms in the, you know, 1660s?

   10. LFLex Fridman33:57

       Good question.

   11. JBJed Buchwald33:58

       County fairs. They were very popular. They were pretty crude with bubbles in them and everything, but they produced colors, so you could buy them at county fairs and things. Very popular.

   12. LFLex Fridman34:08

       Oh, so they were modifying the white light-

   13. JBJed Buchwald34:10

       Well.

   14. LFLex Fridman34:10

       ... to, to create colors.

   15. JBJed Buchwald34:11

       They were creating colors from it, well-known. Um, and what he did was the following. He was, by this time, even though he's very young, a very good mathematician. And he could use the then known laws for how light behaves when it goes through glass to calculate what should happen if you took light from the sun, passed it from a hole, through a little hole, then hit the prism, goes out of the prism, goes strikes a wall a long distance away, and makes a splash of light. Never mind the colors for a moment. Makes a splash of light there. He was very smart. First of all, he abstracts from the colors themselves even though that's what everybody's paying attention to initially. And because what he knows is this, he knows that if you take this prism and you turn it to a certain particular angle that he knew what it should be because he could calculate things, and very few other people in Europe at the time could calculate things like he could, that if you turn the prism to that particular angle, then the sun, which is of course a circle, when its light passes through this little hole and then into the prism, on the far distant wall, should still make a circle.

   16. LFLex Fridman35:34

       Mm.

   17. JBJed Buchwald35:35

       But it doesn't. It makes a very long image. Okay? And, uh, this, uh, led him to a very different conception of light indicating that there are different types of light in the sunlight. Now, to go beyond that, what's particularly interesting I think is the following. When he published, uh, this paper, which got him into a controversy, uh, he really didn't describe at all what he did. He just gave you some numbers. Now I just told you that you had to set this prism at a certain angle, right? You would think, because we do have his notes and so on, um, you would think that he took a, some kind of complicated measuring device to set the prism. He didn't. He held it in his hand. That's all. And he twiddled it around.And what was he doing? It turns out that when you twiddle the prism around, at the point where you should get a circle from a circle, it also is the place where the image does not move very fast.

   18. LFLex Fridman36:43

       Mm.

   19. JBJed Buchwald36:43

       So if you want to get close to there, you just twiddle it. This is manipulative experimentation, taking advantage through his mathematical knowledge of the inherent inaccuracies that label, let you come to exact conclusions regardless of the built-in problematics of measurement. He's the only one I know of doing anything like that.

   20. LFLex Fridman37:11

       At the time.

   21. JBJed Buchwald37:12

       At the time. Yeah.

   22. LFLex Fridman37:14

       Well, even still, there are very few people that are able to have, to calculate as well as he did, to be a theoretician and an experimentalist, like, in the same moment. (laughs) Right?

   23. JBJed Buchwald37:26

       Um, it's, uh, it's true, although until, uh, the, um, really the, well into the 20th century, maybe the beginning of the 20th century really, um, most of the most, uh, significant experimental results produced in the 1800s which laid the foundations for light, electricity, electrodynamics, and so on, um, even in, uh, hydrodynamics and whatnot, were also produced by people who were both excellent calculators, uh, uh, very talented mathematicians, and good with their hands experimentally.

   24. LFLex Fridman38:09

       Mm. And then that led to the 21st century with Enrico Fermi that, uh, one of the, one of the last people that was able to do that, both of those things very well, and that, uh, he built a little device called an atomic bomb that has some positives and negatives.

   25. JBJed Buchwald38:29

       (laughs)

   26. LFLex Fridman38:29

       Many, many different types.

   27. JBJed Buchwald38:29

       Well, right, of course that actually did involve some pretty large-scale elaborate equipment too.

   28. LFLex Fridman38:35

       Yeah, well, holding a light, uh, prism in your hand is the same thing.

   29. JBJed Buchwald38:38

       Uh, right, no. (laughs)

   30. LFLex Fridman38:40

       What, uh, what's the controversy that Newton got into with that paper when he published it?
6. 39:57 – 1:06:10

   Isaac Newton

   1. LFLex Fridman39:57

      can you, uh, can we just step back? Can you say who was Isaac Newton? What are the things he contributed to this world in the space of ideas?

   2. JBJed Buchwald40:07

      Wow. (laughs) Uh, who was he? He was born in, uh, 1642 in, uh, near the small town of Grantham in England. In fact, the house he was born in and that his mother died in is still there and can be visited. Uh, h- his father died before he was born, uh, and his mother eventually remarried, uh, a man named Reverend Smith whom Newton did not like at all, uh, um, because Reverend Smith took his mother away to live with him a few miles away, leaving Newton to be brought up more or less by his grandmother-

   3. LFLex Fridman40:57

      Mm-hmm.

   4. JBJed Buchwald40:57

      ... over there. And he had huge resentment about that his whole life.

   5. LFLex Fridman41:03

      I think that gives you a little inkling that, uh, a little bit of trauma in childhood, maybe a complicated father-son relationship can be useful, uh, to create a good scientist.

   6. JBJed Buchwald41:14

      Could be, although this case it would be right the, you know, absent Father, non-father relationship-

   7. LFLex Fridman41:19

      Non-Father.

   8. JBJed Buchwald41:19

      ... so to speak.

   9. LFLex Fridman41:20

      Gotcha.

   10. JBJed Buchwald41:20

       He was known as a kid, the little that we do know, for, um, being very clever about, uh, flying kites and, uh, there are stories about him putting candles and putting flying kites and scaring the living devil out of people at night by doing that and things like that. Making things. Most of the, uh, uh, physicists and natural philosophers I've dealt with actually, uh, as children were very fond of making and playing with things. I can't think of one I know of who wasn't, actually. They're very good with their hands and whatnot. Uh, he, uh, was, uh, his mother wanted him to take over the manor. It was a kind of farming manor. They were the class of what are known as yeomans. Uh, there are stories that he wasn't very good at that. One day, one of the stories is he's sitting out in the field and the cows come home without him and he doesn't know what's going... Uh, anyway, uh, had relatives and, uh, he manages to get to Cambridge, sent to Cambridge because he's known to be smart. He's read books that he got from local dignitaries and some relatives. Uh, and he goes there as what's known as a subsizar. What does that mean? Well, it's not too pleasant. Basically, a subsizar was a student who had to clean the bedpans of the richer kids.

   11. LFLex Fridman42:47

       Okay.

   12. JBJed Buchwald42:48

       Right? Uh, that didn't last too long. He makes his way, um, and he becomes absorbed in some of the new ways of thinking that are being talked about on the parts of Descartes and others as well. There's also the traditional curriculum which he follows. And we have his notes, we have his n- uh, student notebooks, and so on. We can see gradually this young man's mind focusing and coming to grips with deeper questions of the nature of the world and perception even, and how we know things, and also probing and learning, uh, uh, mathematical structures to such an extent that he builds on some of the investigations that had been done in the period before him to create the foundations of a way of investigating processes that happen and change continuously instead of by leaps and bounds and so on-

   13. LFLex Fridman43:49

       Mm-hmm.

   14. JBJed Buchwald43:49

       ... forming the foundation of what we now call the calculus.

   15. LFLex Fridman43:52

       Calculus. Yeah. So, uh, (laughs) can you maybe just paint a little bit of a picture, you've already started, of what were the things that bothered him the most, that stood out to him the most about the traditional curriculum about the way people saw the world? You mentioned discreet versus continuous. Is there something where he began thinking in a revolutionary way? I mean, it's, 'cause it's fascinating. Most of us go to college, uh, at Cambridge or otherwise, and we just kind of take what we hear as gospel, right? Like, not gospel, but, um, as, like, facts. You don't begin to sort of see, "How can I expand on this aggressively?" Or, "H- how can I challenge everything we, th- that I hear, like, rigorously, mathematically, through the..." I mean, I don't even know how, how rigorous the mathematics was at that point. I'm sure it was geometry and so on. No calculus, huh? (laughs)

   16. JBJed Buchwald44:55

       There, there are elements of what turned into the calculus that predate Newton, but-

   17. LFLex Fridman45:00

       How much, how much rigor was there? How much, uh-

   18. JBJed Buchwald45:03

       Well, rigor-

   19. LFLex Fridman45:04

       ... w-

   20. JBJed Buchwald45:04

       ... no.

   21. LFLex Fridman45:04

       And then, of course, no scientific method, not really.

   22. JBJed Buchwald45:08

       Uh-

   23. LFLex Fridman45:08

       I mean, somewhat, like, I mean, uh, appreciation of data.

   24. JBJed Buchwald45:13

       Ah, that is a separate question from a question of method. Appreciation of data is a significant question, as to what you do with data. There's lots of things you're asking (laughs) here.

   25. LFLex Fridman45:23

       I apologize. So, so maybe let's backtrack and the first question is, was there something that was bothering him that he especially thought he could contribute or work on?

   26. JBJed Buchwald45:34

       Well, of course, we can't go back and talk to him, but we do have these student notebooks. There's two of them. One's called The Philosophical Questions, and the other is called The Waste Book. The Philosophical Questions has discussions of the nature of reality and various issues concerning it. And The Waste Book has things that have to do with motion in various ways, what happens in collisions and things of that sort. And it's a complicated story. But what's among the things that I think are interesting is, he took notes in The Philosophical Questions on stuff that was traditionally, um, given to you in the curriculums going back several hundred years, namely on what, uh, scholars refer to as scholastic or neo-scholastic ways of thinking about the world dating back to the reformulation of Aristotle in the Middle Ages by Thomas Aquinas in the Church. And this is a totally different way of thinking about things, which actually connects to something we were saying a moment ago. For instance, um, uh, so I'm wearing a blue shirt and I will sometimes ask students, "Where is the blue?" And they'll usually say, "Well, it's in your shirt." And then some of them get clever and they say, "Well, no, you know, light is striking it, photons are re-emitted, they strike the back of your retina," and et cetera, et cetera. And I said, "Yes. You, what that means is that the blue is actually an artifact of our perceptual system considered as the percept of blue."

   27. LFLex Fridman47:13

       Mm-hmm.

   28. JBJed Buchwald47:13

       It's not out there, it's in here.

   29. LFLex Fridman47:16

       Yeah.

   30. JBJed Buchwald47:17

       Right? That's not how things were thought about well into the 16th century. The general notion, dating back even to Aristotelian antiquity and formalized by the 12th century, uh, at, uh, Paris, uh, Oxford, and elsewhere, is that qualities are there in the world. They're not in us. We have senses and our senses can be wrong. You know, you could go blind, things like that. But if they're working properly, you get the actual qualities of the world. Now that break, which is v- occurring towards the end of the 16th century and is most visible in Descartes, uh, is the break between conceiving that the qualities of the world are very different from the qualities that we perceive. That, in fact, the qualities of the world consist almost entirely in shapes of various kinds and maybe hard particles or whatever, but not colors, not sounds, not smells, not softness and hardness. They're not in the world, they're in us. That break, Newton is picking up as he reads Descartes. He's gonna disagree with a lot in Descartes. But that break, he is, among other things, picking up very strongly. And that underlies a lot...... of the way he works later on when he becomes skeptical of the evidence provided by the senses.
7. 1:06:10 – 1:16:44

   Competition in Science

   1. JBJed Buchwald1:06:10

      Possibly independently of Newton, because he didn't publish this thing, although, uh, he became quite well-known as quite a brilliant young man, in part because, um, uh, people heard about his work and so on. Uh, when another young, uh, man by the name of Gottfried Leibniz visited London and he heard about these things, uh, it is said that he independently develops, uh, his form of the calculus, which is actually the form we use today, both in notation and perhaps in certain fundamental ways of thinking. It has remained, uh, a controversial point as to where exactly and how much independently Leibniz did it. Leibniz aficionados think and continue to maintain he did it completely independently. Newton, when he became president of the Royal Society, put together a group to go on the attack, saying, "No, he must've taken everything." We don't know. Um, but I will tell you this-... about, uh, 25 or so years ago, a scholar, uh, who's a professor at Indiana now, uh, named Domenico Meli got his hands on a Leibniz manuscript called the Tentamen, which was Leibniz's attempt to produce an alternative to Newton's mechanics.

   2. LFLex Fridman1:07:37

      Mm-hmm.

   3. JBJed Buchwald1:07:38

      And it comes to some conclusions that you have in the Newton's mechanics. Well, he published that, but Meli got the manuscript, and what Meli found out was that Leibniz reverse engineered the Principia and cooked it backwards, so that he could get the results he wanted. Now-

   4. LFLex Fridman1:07:55

      That was for the mechanics, so that means his mind allows for that kind of thing.

   5. JBJed Buchwald1:07:59

      Some people think so.

   6. LFLex Fridman1:08:01

      You're breaking some news today. You're starting some old drama.

   7. JBJed Buchwald1:08:04

      Some people, some people think so. I think most historians of mathematics do not agree with that. Uh, a, uh, friend of mine, rather f- well-known physicist, unfortunately died a couple of years ago, named Mike Nauenburg at UC Santa Cruz, had some evidence along those lines. It didn't pass muster with many of my friends who are historians of math. In fact, I edit with a historian of math, a technical journal, and, uh, we were unable to publish it in there because we couldn't get it through any of our colleagues. Uh, but I am... I remain suspicious.

   8. LFLex Fridman1:08:42

      What is it about those tense relationships and that kind of drama? Einstein doesn't appear to have much of that drama. Nobody claimed... I haven't heard claims that they've... (laughs) perhaps because it's such crazy ideas, of any of his major, uh, inventions, major ideas being those that are, um, basically, "I came up with it first or independently." There's not, as far as I'm aware, not many people talk about general relativity, especially in those terms. But with Newton, that was the case. I mean, is that just a natural outgrowth of how science works is there's going to be personalities that... but I'm not saying this about Leibniz-

   9. JBJed Buchwald1:09:24

      Yeah.

   10. LFLex Fridman1:09:24

       ... but maybe I am, that there's people who, uh, steal ideas for the... you know, because of ego, because of all those kinds of things?

   11. JBJed Buchwald1:09:35

       I don't think it's all that common, frankly. Um, the, the Newton, Hooke, Leibniz, contretemps, and so on, well, you know, you're at the beginnings of a lot of things there, and so on. These, uh, are difficult and complex times as well. These are times in which, um, science as an activity pursued by other than, let us say, interested aristocrats-

   12. LFLex Fridman1:10:01

       Mm.

   13. JBJed Buchwald1:10:02

       ... is becoming something somewhat different. It's not a professional community of investigators in the same way. Uh, it's also a period in which, um, procedures and rules o- of practice are being developed to avoid, um, attacking one another directly and pulling out a sword to cut off the other guy's head if he disagrees with you-

   14. LFLex Fridman1:10:27

       Okay.

   15. JBJed Buchwald1:10:27

       ... and so on. Uh, so it's a very different period. Um, controversies happen. People get angry. I can think of a number of others, including in the development of optics in the 19th century and so on. Uh, and it can get hot under the collar. Um, sometimes one character who's worked an area extensively, whether they've come up with something terribly novel or not, and somebody else kind of moves in and does completely different and novel things, the first guy gets upset about it because he's sort of muscled into what I thought was my area.

   16. LFLex Fridman1:11:05

       Yeah.

   17. JBJed Buchwald1:11:06

       You find that sort of stuff.

   18. LFLex Fridman1:11:07

       But, uh, do you have examples of cases where it worked out well, like, uh, that competition is good for the progress of science?

   19. JBJed Buchwald1:11:15

       Yeah, it almost always is good in that sense, so...

   20. LFLex Fridman1:11:17

       (laughs) It's just painful for the individuals involved.

   21. JBJed Buchwald1:11:20

       Can be, yeah. It doesn't have to be, you know, nasty, although sometimes it is.

   22. LFLex Fridman1:11:25

       So on a space... like for the example with optics, could you comment on that one?

   23. JBJed Buchwald1:11:29

       Well, yeah, sure. Let me... there are several, but I could give you, um... All right, so I'll give you this example that probably is the most pertinent. Um, the first, uh, polytechnic school, like MIT or Caltech, was actually founded in France during the French Revolution. It exists today. It's the Ecole Polytechnique.

   24. LFLex Fridman1:11:54

       Mm-hmm.

   25. JBJed Buchwald1:11:55

       All right? Uh, two people who were there, uh, were two young men in the 90s, 1790s, uh, named, on the one hand Francois Arago and the other Jean-Baptiste Biot. They both lived a long time, well into the 1850s. Arago became a major administrator of science and Biot's career started to peter out after about the late teens. Now, they are, uh, sent on an expedition, which was one of the expeditions involving measuring things to start the metric system.

   26. LFLex Fridman1:12:34

       Mm-hmm.

   27. JBJed Buchwald1:12:34

       There's a lot more to that story. Anyway, they come back. Arago gets separated. He's captured, uh, by, uh, pirates actually.

   28. LFLex Fridman1:12:45

       (laughs)

   29. JBJed Buchwald1:12:45

       Winds up in, uh, Tangier, escapes, is captured again. Everybody thinks he's dead. He gets back to Paris and so on. He's greeted as a hero and whatnot. In the meantime, Biot has pretty much published some of the stuff that he's done and Arago doesn't get much credit for it, and Arago g- starts to get very angry. And Biot is known for this kind of thing. So Arago... Anyway, Biot starts investigating a new phenomenon in optics involving something called polarization.

   30. LFLex Fridman1:13:21

       Mm-hmm.
8. 1:16:44 – 1:29:55

   Newton's Career

   1. JBJed Buchwald1:16:44

      He had a complicated young life, as we've said. Um, he had always been, um, very self-contained and solitary. He had acquaintances in France, and when he moved to London eventually, he had quite a career, a, a career for instance, that led him when he was famous by then, the 1690s, he moves to London. He becomes first, um, Warden of the Mint. The mint is what produces coins, and coinage was a complicated thing 'cause there was counterfeiting going on.

   2. LFLex Fridman1:17:17

      Yes.

   3. JBJed Buchwald1:17:18

      And he becomes Master of the Mint, to the extent, uh, and a guy at MIT, uh, wrote a book about this a little bit. We wrote something on it too. I forget, his name was Levin. Um, that Newton sent investigators out to catch these guys and sent at least one of them, a famous one named Chaloner, to the gallows.

   4. LFLex Fridman1:17:39

      Hm.

   5. JBJed Buchwald1:17:40

      So he was... Uh, he, and, and one of the reasons he probably was so particularly angry at Chaloner, was Chaloner had apparently said some nasty things about Newton in front of Parliament at some point.

   6. LFLex Fridman1:17:54

      Fair enough. Yeah.

   7. JBJed Buchwald1:17:55

      That was apparently not a good idea.

   8. LFLex Fridman1:17:57

      Well, he had a bit of a temper. So Newton had a bit of a temper.

   9. JBJed Buchwald1:17:59

      Clearly.

   10. LFLex Fridman1:18:00

       Okay.

   11. JBJed Buchwald1:18:01

       Clearly. Um, but he, um, he even as a young man at, uh, Cambridge, though he doesn't come from wealth, he attracts, um, uh, people who recognize his smarts. Uh, he, there's a young fellow named Humphrey Newton, uh, shared his rooms, you know, these students always shared rooms with one another, uh, became his kind of amanuensis to, uh, write down what Newton was doing and so on. Uh, and, um, there were others over time, uh, who he befriended in various ways and so on. He was solitary. Uh, he had, as far as we know, no relationships with either women or men in, uh, anything other than a formal way. Uh, the only-

   12. LFLex Fridman1:18:49

       Those get in the way, relationships.

   13. JBJed Buchwald1:18:51

       Right. Well, I mean-

   14. LFLex Fridman1:18:52

       The distractions.

   15. JBJed Buchwald1:18:52

       ...he was, he, uh, he was... I don't know if he was close to his mother. I mean, she passed away, everything left him, he went to be with her after she died. He was close to his niece, Catherine Barton, who basically came to run his household, uh, when he moved to London and so on. And she married, uh, a man named Conduitt, who became one of the, um, uh, people who controlled Newton's legacy later on, and so on. So he... And, and, and you can even see the house that, the townhouse that Newton lived in in those days, still there.

   16. LFLex Fridman1:19:31

       Nice. So there's the, the story of, uh, Newton coming up with quite a few ideas, uh, during a pandemic.We're, uh, on the outskirts-

   17. JBJed Buchwald1:19:41

       (laughs)

   18. LFLex Fridman1:19:41

       ... of a pandemic ourselves.

   19. JBJed Buchwald1:19:42

       Right.

   20. LFLex Fridman1:19:43

       And a lot of people use that example as motivation for everybody (laughs) while they're in lockdown to get stuff done. Uh, so what's that about? Can you tell the story of that?

   21. JBJed Buchwald1:19:53

       Well, I can. Let me first say that, uh, of course we've been teaching over Zoom-

   22. LFLex Fridman1:19:57

       Over Zoom.

   23. JBJed Buchwald1:19:57

       ... lately. And-

   24. LFLex Fridman1:19:58

       There was no Zoom back then?

   25. JBJed Buchwald1:20:00

       Yeah, (laughs) there was no Zoom back then.

   26. LFLex Fridman1:20:01

       Right.

   27. JBJed Buchwald1:20:01

       Right? Although, it wouldn't have made much difference because the story was Newton was so complicated in his lectures that at one point, uh, Humphrey Newton actually said that, uh, he might as well have just been lecturing to the walls 'cause nobody was there-

   28. LFLex Fridman1:20:13

       Yeah.

   29. JBJed Buchwald1:20:13

       ... to listen to it, so what difference. But, uh-

   30. LFLex Fridman1:20:16

       Also not a great teacher, huh?
9. 1:29:55 – 1:36:13

   Importance of Data

   1. LFLex Fridman1:29:55

      Where does data fit into this? We kind of earlier in the discussion, uh, mentioned data as part of the scientific method. How important was data to Newton?

   2. JBJed Buchwald1:30:08

      Okay.

   3. LFLex Fridman1:30:09

      So like you mentioned, uh, prism and playing with it and looking at stuff and then coming up with calculations and so on. Where does data fit into any of his ideas?

   4. JBJed Buchwald1:30:18

      All right, well, let me say two things first. One, we rarely use the phrase scientific method anymore because there is no one easily describable such method. In a certain, I mean, humans have been playing around with the world and learning how to repetitively do things and make things happen ever since, you know, humans became humans.

   5. LFLex Fridman1:30:41

      Mm-hmm.

   6. JBJed Buchwald1:30:41

      Um, the question-

   7. LFLex Fridman1:30:42

      Do you have, do you have a preferred definition of the scientific method? What are the various-

   8. JBJed Buchwald1:30:46

      Uh, uh, no, I don't. I prefer to talk about, um, the considered manipulation of artificial structures to produce results that can be worked together with schemes to construct other devices and make, uh, predictions, if you will, about the way such things will work.

   9. LFLex Fridman1:31:14

      So ultimately, it's about producing other devices. It like leads you down a-

   10. JBJed Buchwald1:31:19

       I think so, principally. Uh, I mean, you may have data, if you will, like astronomical data obtained otherwise and so on, but yes. And, but, but, but number two here is this question of data. What is data in that sense? See, when we talk about data today, um, we have a kind of complex notion which reverts to even issues of statistics and measurement procedures and so on.

   11. LFLex Fridman1:31:48

       Mm-hmm.

   12. JBJed Buchwald1:31:49

       So, uh, l- let me put it to you this way. So let's say I had a ruler in front of me.

   13. LFLex Fridman1:31:55

       Go on.

   14. JBJed Buchwald1:31:55

       And it's marked off in little black marks, separated by, let's say, distances a-... called a millimeter, okay? Now I make a mark on this piece of paper here. So I made a nice black mark, right? Nice black mark. And I ask you, I want you to measure that and tell me how long it is. You're gonna take the ruler, you're gonna put it next to it, and you're gonna look, and it's not gonna sit, even if you put one end as close as you can on one black mark, the other end probably isn't going to be exactly on a black mark.

   15. LFLex Fridman1:32:31

       Yeah.

   16. JBJed Buchwald1:32:31

       Well, you'll say it's closer to this or that, and you'll write down a number. And I say, "Okay, take the ruler away a minute." I take this away. "Come back in five minutes, put the piece of paper down, and do it again." You're gonna probably come up with a different number.

   17. LFLex Fridman1:32:44

       Yeah.

   18. JBJed Buchwald1:32:45

       And you're gonna do that a lot of times. And then if I tell you, "I want you to give me your best estimate of what the actual length of that thing is," what are you gonna do? You're going to average all of these numbers. Why?

   19. LFLex Fridman1:33:04

       Statistics.

   20. JBJed Buchwald1:33:06

       Well, yes, statistics.

   21. LFLex Fridman1:33:08

       (laughs)

   22. JBJed Buchwald1:33:08

       There's lots of ways of going around it, but the average is the best estimate on the basis of what's called the central limit theorem, a statistical theorem. We are talking about things, uh, that were not really developed until the 1750s, 60s, and 70s.

   23. LFLex Fridman1:33:25

       Mm-hmm.

   24. JBJed Buchwald1:33:25

       Newton died in 1727.

   25. LFLex Fridman1:33:27

       The, the intuition perhaps was there.

   26. JBJed Buchwald1:33:28

       Not really. I'll tell you what people did, including Newton, although Newton is partially the one exception. We talked a while ago about this guy, Christiaan Huygens. He measured lots of things, and he was a good, uh, mechanic himself.

   27. LFLex Fridman1:33:44

       Mm-hmm.

   28. JBJed Buchwald1:33:44

       He and his brother ground lenses. Huygens, I told you, developed the first pendulum mechanism, pendulum-driven clock with a mechanism, and so on. Also, a spring watch, where he got into a controversy with Hooke over that, by the way. Um, now-

   29. LFLex Fridman1:34:00

       What's with these mechanics and the controversy?

   30. JBJed Buchwald1:34:02

       Well, they get in an argument.
10. 1:36:13 – 1:40:28

    Alchemy

    1. LFLex Fridman1:36:13

       Okay, let me ask you again, for a friend, about, uh, this alchemy thing. You know, it'd be nice to create gold, but it also seems to, uh, come into play quite a bit throughout the history of science, uh, perhaps in positive ways, in terms of its impact. Can you say something to the history of alchemy?

    2. JBJed Buchwald1:36:34

       A little bit.

    3. LFLex Fridman1:36:34

       And its impact?

    4. JBJed Buchwald1:36:35

       Sure. Um, it used to be thought two things. One, that alchemy, which dates certainly back to the Islamic period, in Islam. Uh, you're talking, you know, 11th, 12th, 13th centuries, uh, among Islamic natural philosophers and experimenters. Uh, but it used to be thought that, um, alchemy, which picked up strikingly in the 15th, 16th century, 1500s and thereabouts, uh, was a sort of mystical procedure involving all sorts of strange notions and so on. And that's not entirely untrue, but it is substantially untrue, in that alchemists were engaged in what, uh, was known as chrysopoieia. That is, looking for ways to transform, um, invaluable materials into valuable ones.

    5. LFLex Fridman1:37:35

       Mm-hmm.

    6. JBJed Buchwald1:37:36

       But in the process of doing so, or attempting to do so, they, uh, learned how to, uh, create complex amalgams of various kinds. They used very elaborate apparatus, glass alembics, in which they would use heat to produce chemical decompositions. They would write down and observe these compositions. And many of the so-called really strange-looking alchemical formulas and statements, where they'll say something like, I, I can't produce it, but it would be, "The sole of Mars will combine with the," this-

    7. LFLex Fridman1:38:15

       Yes.

    8. JBJed Buchwald1:38:16

       ... et cetera, et cetera. These...... it has been shown are almost all actual formulas for how to engage in the production of complex amalgams.

    9. LFLex Fridman1:38:26

       Mm-hmm.

    10. JBJed Buchwald1:38:26

        And what to do. And by the time of Newton, Newton was reading the works of a, uh, fellow by the name of Starkey, who was actually came from Harvard, um, uh, shortly before, in which, um, things had progressed, if you will, to the point where the procedure turns into what historians call chrysopoieia, which basically runs into the notion of thinking that may, these things are made out of particles. This is the mechanical philosophy. Can we engage in processes, chemical processes, to rearrange these things? Which is not so stupid, after all.

    11. LFLex Fridman1:39:09

        Mm-hmm.

    12. JBJed Buchwald1:39:10

        I mean, we do it, except we happen to do it in reactors, not in chemical processes. Unless, of course, it had happened that cold fusion had worked, which it didn't. Um-

    13. LFLex Fridman1:39:20

        Not yet.

    14. JBJed Buchwald1:39:21

        Well, right. But, um, so that's the way they're thinking about these things. There's a kind of mix. And Newton engages extensively in those sorts of manipulations. In fact, more in that than almost anything else, uh, except for his optical investigations. If you look through the latter parts of the 1670s, the last five, six, seven years or so of that, there's more on that than there is on anything else.

    15. LFLex Fridman1:39:51

        Huh.

    16. JBJed Buchwald1:39:51

        He's not working on mechanics. He's pretty much gone pretty far in optics. He'll turn back to optics later on.

    17. LFLex Fridman1:39:58

        So optics and alchemy. So what you're saying is, Isaac Newton liked shiny things.

    18. JBJed Buchwald1:40:05

        Well, actually if you go online and look at what Bill Newman, the professor at Indiana, uh, at, uh, Bloomington, Indiana, has produced, you'll find the very shiny thing called the Star Regulus, which Newton describes as having produced according to a particular way, which Newman figured out and was able to do it. And it's very shiny. (laughs)

    19. LFLex Fridman1:40:26

        (laughs) There you go. It proves the theorem.

11. 1:40:28 – 1:43:41

    Newton and Religion

    1. LFLex Fridman1:40:28

       Uh, can I ask you about God, religion, and its role in Newton's life? Was there helpful, constructive, or destructive influences of religion in his work and i- and in his life?

    2. JBJed Buchwald1:40:48

       Well, there you begin to touch on a complex question. Um, the role that God played would be an interesting question to answer, should one go and be able to speak with this invisible character who doesn't exist. But putting that aside for the moment...

Episode duration: 1:52:16