back to indexJed Buchwald: Isaac Newton and the Philosophy of Science | Lex Fridman Podcast #214
link |
The following is a conversation with Jed Buckwald, a professor of history and a philosopher of
link |
science at Caltech, interested especially in the development of scientific concepts
link |
and the instruments used to create and explore new effects and ideas in science.
link |
To support this podcast, please check out our sponsors in the description.
link |
This is the Lex Friedman podcast and here is my conversation with Jed Buckwald.
link |
Does science progress via paradigm shifts and revolutions, as philosopher Thomas Kuhn said,
link |
or does it progress gradually? What do you think?
link |
Well, I got into this field because I was Tom Kuhn's research assistant 50 years ago, 52 years
link |
ago. He pulled me into it out of physics instead. So I know his work pretty well. And in the years
link |
when I was at MIT running an institute, he was then in the philosophy department, used to come
link |
over all the time to the talks we held and so on. So what would I say about that? He of course
link |
developed his ideas a lot over the years. The thing that he's famous for, the structure of
link |
scientific revolutions came out in 62. And as you just said, it offered an outline for what he
link |
called a paradigmatic structure, namely the notion that you have to look at what scientists do
link |
is forming a community of investigators and that they're trying to solve various puzzles,
link |
as he would put it, that crop up, figuring out how this works, how that works, and so on.
link |
And of course, they don't do it out of the blue, they do it within a certain framework. The framework
link |
can be pretty vague. He called it a paradigm. And his notion was that eventually they run into
link |
troubles or what he called anomalies, that kind of cracks things, somebody new comes along with
link |
a different way of doing it, etc. Do I think things work that way? No, not really. Tom and I used to
link |
have like the discussions about that over the years. I do think there is a common structure
link |
that formulates both theoretical and experimental practices. And historians nowadays of science
link |
like to refer to scientific work as what scientists practice. It's almost craftsmen like.
link |
They can usually adapt in various ways. And I can give you all kinds of examples of that.
link |
I once wrote a book on the origins of wave theory of light. And that is one of the
link |
paradigmatic examples that Tom used, only it didn't work that way exactly. Because he thought
link |
that what happened was that the wave theory ran into trouble with a certain phenomenon
link |
which it couldn't crack. Well, it turned out that in fact, historically that phenomenon was
link |
actually not relevant later on to the wave theory. And when the wave theory came in,
link |
the alternative to it, which had prevailed, which was Newton's views, light as particles,
link |
that it seemed couldn't explain what the wave theory could explain. Again, not true.
link |
Not true. Much more complex than that. The wave theory offered the opportunity to deploy
link |
novel experimental and mathematical structures which gave younger scientists, mathematicians
link |
and others the opportunity to effect, manufacture, make new sorts of devices. It's not that the
link |
alternative couldn't sort of explain these things, but it never was able to generate them
link |
de novo as novelties. In other words, if you think of it as something scientists want to
link |
progress in the sense of finding new stuff to solve, then I think what often happens is,
link |
is that it's not so much that the prevailing view can't crack something as that it doesn't give you
link |
the opportunity to do new stuff. When you say new stuff, are we referring to experimental science
link |
here or new stuff in the space of new theories? Could be both. Could be both, actually. So how
link |
does that, can you maybe elaborate a little bit on the story of the wave? Sure. The prevailing view
link |
of light, at least in France, where the wave theory really first took off, although it had
link |
been introduced in England by Thomas Young. The prevailing theory dates back to Newton,
link |
that light is a stream of particles and that refraction and reflection involve sort of repulsive
link |
and attractive forces that deflect and bend the paths of these particles. Newton was not able
link |
successfully to deal with the phenomenon of what happens when light goes past a knife's edge
link |
or a sharp edge, what we now call diffraction. He had cooked up something about it that no
link |
mathematical structure could be applied. Thomas Young first, but really this guy named Augustin
link |
Frenel in France, deployed, in Frenel's case, rather advanced calculus forms of mathematics,
link |
which enabled computations to be done and observations to be melded with these computations
link |
in a way that you could not do or see how to do with Newton. Did that mean that the Newtonian
link |
explanation of what goes on in diffraction fails? Not really. You can actually make it work, but
link |
you can't generate anything new out of it, whereas using the mathematics of wave optics
link |
in respect to a particular phenomenon called polarization, which ironically was discovered
link |
by partisans of Newton's way of doing things, you were able to generate devices which reflect
link |
light in crystals, do various things that the Newtonian way could accommodate only after the
link |
fact they couldn't generate it from the beginning. And so if you want to be somebody who is working
link |
a novel vein, which increasingly becomes the case with people who become what we now call
link |
physicists in the 1820s, 30s, and 40s in particular, then that's the direction you're going to go.
link |
But there were holdouts until the 1850s. I want to try to elaborate on the nature of the
link |
disagreement you have with Thomas Kuhn. Do you still believe in paradigm shifts? Do you still
link |
see that there is ideas that really have a transformational effect on science? The nature
link |
of the disagreement has to do with how those paradigm shifts come to be? How they come to be
link |
and how they change. I certainly think they exist. How strong they may be at any given time is maybe
link |
not quite as powerful as Tom thought in general, although towards the end of his life he was beginning
link |
to develop different modifications of his original way of thinking. But I don't think that the changes
link |
happen quite so neatly, if you will, in reaction to novel experimental observations. They get much
link |
more complex than that. In terms of neatness, how much of science progresses by individual
link |
lone geniuses and how much by the messy collaboration of competing and cooperating humans?
link |
I don't think you can cut that with a knife to say it's this percent and that percent.
link |
It's almost always the case that there are one or two or maybe three individuals who are sort
link |
of central to what goes on when things begin to shift. Are they inevitably and solely responsible
link |
for what then begins to happen in a major way? I think not. It depends. You can go very far back
link |
with this even into antiquity to see what goes on. The major locus we always talk about from the
link |
beginning is if you're talking about Galileo's work on motion, for example, were there ways of
link |
accommodating it that others could adapt to without buying into the whole scheme? Yes. Did it
link |
eventually evolve and start convincing people because you could also do other things with it
link |
that you couldn't otherwise do? Also, yes. Let me give you an example. The great French
link |
mathematician philosopher Descartes, who was a mechanical philosopher, he believed the world was
link |
matter in motion. He never thought much of what Galileo had done in respect to motion
link |
because he thought, well, it bested some sort of approximative scheme or something like that.
link |
But one of his initial, I wouldn't call him a disciple, but follower, who then broke with him
link |
in a number of ways, was a man named Christian Huygens, who was along with Newton, one of the
link |
two greatest scientists of the 17th century, Huygens is older than Newton, and Huygens nicely
link |
deployed Galilean relationships in respect to motion to develop all sorts of things,
link |
including the first pendulum governed clock and even figured out how to build one,
link |
which keeps perfect time, except it didn't work, but he had the mathematical structure for it.
link |
How well known is Huygens? Oh, very well known.
link |
Should I know him well? Yes, you should.
link |
Interesting. You should definitely know him well.
link |
No, no, no, no. Can we define should here? Okay.
link |
Because I don't. Right. So, is this should like a, yeah, can you define should?
link |
Should means this. If you had taken up to a second year of physics courses, you should,
link |
you would have heard his name because one of the fundamental principles and optics is called
link |
Huygens principle. Okay.
link |
Okay. Yeah, so I have, and I have heard his name. There you go.
link |
No, but I don't remember. But you don't remember.
link |
So, I mean, there's, there's a very different thing between names attached to principles and
link |
laws and so on that you sometimes let go of. You just remember the equations of the principles
link |
themselves and the personalities of science. And there's certain personalities, certain human
link |
beings that stand out. And that's why there is a sense to which the lone inventor, the lone
link |
scientist is the way I personally, I mean, I think a lot of people think about the history of science
link |
is these lone geniuses without them. The sense is if you remove Newton from the picture,
link |
if you remove Galileo from the picture, then science would, there's almost a feeling like
link |
it would just have stopped there. Or at the very least, there's a feeling like it would
link |
take much longer to develop the things that were developed. Is that a silly way to look at the
link |
history? That's not entirely incorrect, I suppose. I find it difficult to believe that had Galileo
link |
not existed, that eventually someone like Huygens, for instance, given the context of the times,
link |
what was floating around in the belief structure concerning the nature of the world and so on,
link |
the developments in mathematics and whatnot, that sooner or later, whether it would have been
link |
exactly the same or not, I cannot say. But would things have evolved? Yes.
link |
If we look at the long arc of history of science from back when we were in the caves,
link |
trying to knock two rocks together, or maybe make a basic tool to
link |
do a long time from now, many centuries from now, when human civilization finally destroys itself.
link |
If we look at that history, and imagine you're a historian at the end, like with the fire,
link |
the apocalypse coming upon us, and you look back at this time in the 21st century,
link |
how far along are we on that arc? Do you sense? Have we invented and discovered everything that's
link |
to be discovered, or are we at like below 1%? Well, you're going to get a lot of absurd questions
link |
today. I apologize. It's a Lugubrius picture you're painting there. I don't even know what
link |
the word Lugubrius is, but I love it. Lugubrius. Well, let me try and separate the question of
link |
whether we're all going to die in an apocalypse in several hundred years or not, from the question
link |
of where science may be sitting. Take this as an assumption.
link |
I find that hard to say, and I find it hard to say because in the deepest sense of the term,
link |
as it's usually deployed by philosophers of science today, I'm not fundamentally a realist.
link |
That is to say, I think our access to the inner workings of nature is inevitably mediated by
link |
what we can do with the materials and factors around us. We can probe things in various ways.
link |
Does that mean that I don't think that the standard model in quantum electrodynamics
link |
is incorrect? Of course not. I wouldn't even dream of saying such a thing. It can do a lot,
link |
especially when it comes to figuring out what's happening in very large expensive
link |
particle accelerators and applying results in cosmology and so on as well.
link |
Do I think that we have inevitably probed the depths of reality through this? I do not agree
link |
with Steven Weinberg who thinks we have about such things. Do I, on the other hand, think that
link |
the way in which science has been moving for the last hundred years, physics in particular is what
link |
I have in mind, will continue on the same course in that sense? I don't because we're not going
link |
to be building bigger and bigger and more and more expensive machines to rip apart particles
link |
in various ways. In which case, what are physicists going to do? They'll turn their
link |
attention to other aspects. There are all sorts of things we've never explained about the material
link |
world. We don't have theories that go beyond a certain point for all sorts of things.
link |
Can we, for example, start with the standard model and work our way up all the way to chemical
link |
transformations? You can make an argument about it and you can justify things, but in chemistry,
link |
that's not the way people work. They work with much higher level quantum mechanical relationships
link |
and so on. This notion of the deep theory to explain everything is a longstanding belief
link |
which goes back pretty far, although I think it only takes its fullest form
link |
sometime towards the end of the 19th century. Maybe we just speak to that. You're referring to
link |
a hope, a dream, a reality of coming up with a theory of everything that explains everything.
link |
There's a very specific thing that that currently means in physics,
link |
is the unification of the laws of physics, but I'm sure in antiquity or before it meant maybe
link |
something else or was it always about physics? I think as you've kind of implied,
link |
in physics there's a sense once you get to the theory of everything you've understood everything,
link |
but there's a very deep sense in which you've actually understood not very much at all.
link |
You've understood at that particular level how things work, but you don't understand how the
link |
abstractions on top of abstractions form all the way to the chemistry, to the human mind,
link |
and the human societies, and all those kinds of things. Maybe you can speak to the theory of
link |
everything in its history and comment on what the heck does that even mean, the theory of everything.
link |
Well, I don't think you can go back that far with something like that, maybe at best to the
link |
17th century. If you go back all the way in antiquity, there are of course discussions about
link |
the nature of the world, but first of all, you have to recognize that the manipulative
link |
character of physics and chemistry, the probing of, let me put it this way, we assume and have
link |
assumed for a long time, I'll come back to when in a moment, that if I take a little device which
link |
is really complicatedly made out of all kinds of things, and I put a piece of some material in it,
link |
and I monkey around with it and do all kinds of unnatural things to it, things that wouldn't
link |
happen naturally, and I find out how it behaves and whatnot, and then I try and make an argument
link |
about how that really applies even in the natural world without any artificial structures and so on.
link |
That's not a belief that was widely held by pretty much anyone until sometime maybe in the 1500s,
link |
and when it was first held, it was held by people we now call alchemists.
link |
So alchemy was the first, the early days of the theory of everything, of a dream of a theory of
link |
everything. I would put it a little differently, I think it's more along the way a dream that by
link |
probing nature in artificially constructed ways, we can find out what's going on deep down there.
link |
So that was that's distinct from science being an observing thing, where you observe nature
link |
and you study nature. You're talking about probing, like messing with nature to understand it.
link |
Indeed I am, and but that of course is the very essence of experimental science. You have to
link |
manipulate nature to find out things about it, and then you have to convince others that you
link |
haven't so manipulated it that what you've done is to produce what amounts to fake
link |
artifactual behavior that doesn't really hold purely naturally.
link |
So where are we today in your sense to jump around a little bit with the theory of everything?
link |
Maybe a quick kind of sense you have about the journey in the world of physics that we're taking
link |
towards the theory of everything. Well, I'm of course not a practicing physicist. I mean,
link |
I was trained in physics at Princeton a long time ago. Until Thomas Kuhn stole you away.
link |
More or less, I was taking graduate courses in those days in general relativity. I was an
link |
undergraduate, but I moved up and then I took a course with him and... Well, you made the mistake
link |
of being compelled by charismatic philosophers and never looked back. I suppose so in a way.
link |
From what I understand, talking especially to my friends at Caltech, like Kip Thorne and others,
link |
the fundamental notion is that actually the laws that even at the deepest level we can
link |
sort of divine and work with in the universe that we inhabit are perhaps quite unique to this
link |
particular universe as it formed at the Big Bang. The question is, how deep does it go?
link |
If you are very mathematically inclined, the prevailing notion for several decades now has
link |
been what's called string theory, but that has not been able to figure a way to generate
link |
probative experimental evidence, although it's pretty good apparently at accommodating things.
link |
Then the question is, what's before the Big Bang? Actually, the word before doesn't mean anything,
link |
given the nature of time, but why do we have the laws that prevail in our universe?
link |
Well, there is a notion that those laws prevail in our universe because if they didn't, we wouldn't
link |
be here. That's a bit of a cyclical, but nevertheless a compelling definition. There's
link |
all kinds of things like, it seems like the unification of those laws could be discovered
link |
by looking inside of a black hole because you get both the general relativity and the quantum
link |
mechanics, quantum field theory in there. Experimentally, of course, there's a lot of
link |
interesting ideas. We can't really look close to the Big Bang. We can look that far back.
link |
This in Caltech and MIT will lie go looking at gravitational waves, perhaps allows us to march
link |
backwards and so on. Yeah, it's really exciting space. There's, of course, the theory of everything
link |
with a lot of things in science captivates the dreams of those who are perhaps completely
link |
outside of science. It's the dream of discovering the key to how the nature of how everything works.
link |
That feels deeply human. That's perhaps the thing, the basic elements of what makes up
link |
a scientist in the end is that curiosity, that longing to understand.
link |
Let me ask, you mentioned a disagreement with Weinberg on reality. Could you elaborate a little
link |
bit? Well, obviously, I don't disagree with Steve Weinberg on physics itself. I wouldn't
link |
know enough to even begin to do that. Clearly, he's one of the founders of the standard model
link |
and so on. It works to a level of accuracy that no physical theory has ever worked at before.
link |
I suppose the question in my mind is something that, in one way, could go back to the philosopher
link |
Immanuel Kant in the 18th century. Namely, can we really ever convince ourselves that we have
link |
come to grips with something that is not in itself knowable to us by our senses or even except in
link |
the most remote way through the complex instruments that we make as to what it is that underlies
link |
everything? Can we corral it with mathematics and experimental structures? Yes. Do I think that
link |
a particular way of corraling nature will inevitably play itself out? I don't know.
link |
It always has. I'll put it to you that way.
link |
All right. The basic question is, can we know reality? Is that the Kant question? Is that
link |
the Weinberg question? We humans with our brains, can we comprehend reality? Sounds like a very
link |
trippy question because a lot of it rests on definitions of know and comprehend and reality, but
link |
get to the bottom of it. It's turtles on top of turtles. Can we get to the bottom turtle?
link |
Well, maybe I can put it to you this way in a way that I often begin discussions in a class on
link |
the history of science and so on and say, I'm looking at you. Yes. You are in fact a figment of
link |
my imagination. You have a messed up imagination. Yes. Well, what do I mean by that? If I were a
link |
dragonfly looking at you, whatever my nervous system would form by way of a perceptual structure
link |
would clearly be utterly different from what my brain and perceptual system altogether is forming
link |
when I look at you. Who's right? Is it me or the dragonfly?
link |
Well, the dragonfly is certainly very impressive, so I don't know. But yes, it's the observer matters.
link |
Well, what is that supposed to tell us about objective reality?
link |
Well, I think it means that it's very difficult to get beyond the constructs that our perceptual
link |
system is leading us to. When we make apparatus and devices and so on, we're still making things,
link |
the results of which or the outputs of which we process perceptually in various ways.
link |
An analogy I like to use with the students sometimes is this. All right, they all have their
link |
laptops open in front of them, of course. And I've sent them something to read and I say,
link |
okay, click on it and open it up. So PDF opens up. I said, what are you looking at?
link |
I said, well, I'm looking at the paper that you sent me. I said, no, you're not.
link |
What you're looking at is a stream of light coming off LEDs or LCDs coming off a screen.
link |
And I said, what happens when you use your mouse and move that fake piece of paper on the screen
link |
around? What are you doing? You're not moving a piece of paper around, are you? You're moving a
link |
construct around, a construct that's being processed so that our perceptual system can
link |
interact with it in the way we interact with pieces of paper. But it's not real.
link |
So are there things outside of the reach of science? Can you maybe, as an example, talk about
link |
consciousness, masking for a friend, trying to figure this thing out?
link |
Well, boy, I mean, I read a fair bit about that, but I certainly can't really say much about it.
link |
I'm a materialist in the deepest sense of the term. I don't think there is anything out there
link |
except material structures which interact in various ways. Do I think, for example,
link |
that this bottle of water is conscious? No, I do not. Although how would I know? I can't talk to it.
link |
But so what do… It's a hypothesis, yeah. It's an opinion, an educated opinion that may be very
link |
wrong. Well, I know that you're conscious because I can interact directly with you.
link |
But am I? Well, unless you're a figment of my imagination, of course.
link |
Nor am I a robot that's able to generate the illusion of consciousness effectively enough
link |
to facilitate a good conversation because we humans do want to pretend that we're talking
link |
to other conscious beings because that's how we respect them. If it's not conscious,
link |
we don't respect them. We're not good at talking to robots.
link |
That's true. Of course, we generalize from our own inner sense, which is the kind of thing Des
link |
Cartes said from the beginning. We generalize from that. But I do think that consciousness must be
link |
something, whatever it is, that occurs as a result of some particular organizational structure of
link |
material elements. Does materialism mean that it's all within the reach of science?
link |
My sense would be that especially as neuroscience progresses more and more, and at Caltech,
link |
we just built a whole neuroscience arena and so on. And as more knowledge is gained about the ways
link |
in which animals, when they behave, what patterns show up at various parts of the brain and nervous
link |
system, and perhaps extending it to humans eventually as well, we'll get more of a handle
link |
on what brain activity is associated with experiences that we have as humans. Can we move
link |
from the brain activity to the experiences in terms of our person? No, you can't. Perception
link |
is perception. That's a hypothesis once again. Maybe consciousness is just one of the laws of
link |
physics that's yet to be discovered. Maybe it permeates all matter. Maybe it's as simple as
link |
trying to plug it in and plug into the ability to generate and control that kind of law of physics
link |
that would crack open where we would understand that the bottle of water is in fact conscious,
link |
just much less conscious than us humans, and then we would be able to then generate beings that are
link |
more conscious. Well, that'll be unfortunate. I'd have to stop drinking the water after that.
link |
Every time you take a sip, there's a little bit of a suffering going on. What to use the
link |
most interesting beautiful moments in the history of science? What stands out?
link |
And then we can pull at that thread. Right. Well, I like to think of events that have
link |
a major impact and involve both beautiful conceptual, mathematical, if we're talking
link |
physical structures work and are associated as well with probing experimental situations.
link |
So among my favorites is one of the most famous, which was the young Isaac Newton's work with
link |
the colors produced when you pass sunlight through a prism. And why do I like that?
link |
It's not profoundly mathematical in one sense. It doesn't need it initially. It needs the
link |
following though, which begins to show you, I think, a little bit about what gets involved
link |
when you've got a smart individual who's trying to monkey around with stuff and finds new things
link |
about it. First, let me say that the notion, the prevailing notion going back to antiquity,
link |
was that colors are produced in a sense by modifying or tinting white light, that they're
link |
modifications of white light. In other words, the colors are not in the sunlight in any way.
link |
Now, what Newton did following experiments done by Descartes before him, who came to very different
link |
conclusions, he took a prism, you might ask, where do you get prisms in the 1660s, county fairs.
link |
They were very popular. They were pretty crude with bubbles in them and everything,
link |
but they produced colors. So you could buy them at county fairs and things very popular.
link |
So they were modifying the white light to create colors.
link |
Well, they were creating colors from it, well known. And what he did was the following. He was
link |
by this time, even though he's very young, a very good mathematician. And he could use the then
link |
known laws for how light behaves when it goes through glass to calculate what should happen
link |
if you took light from the sun, passed it from a hole through a little hole, then hit the prism,
link |
goes out of the prism, goes, strikes a wall a long distance away, and makes a splash of light.
link |
Never mind the colors for a moment. Makes a splash of light there. He was very smart.
link |
First of all, he abstracts from the colors themselves, even though that's what everybody's
link |
paying attention to initially. Because what he knows is this. He knows that if you take this
link |
prism and you turn it to a certain particular angle, that he knew what it should be because he
link |
could calculate things. Very few other people in Europe at the time could calculate things
link |
like he could. That if you turn the prism to that particular angle, then the sun, which is,
link |
of course, a circle, when its light passes through this little hole and then into the prism,
link |
on the far distant wall, should still make a circle. But it doesn't. It makes a very long
link |
image. And this led him to a very different conception of light, indicating that there are
link |
different types of light in the sunlight. Now, to go beyond that, what's particularly interesting,
link |
I think, is the following. When he published this paper, which got him into a controversy,
link |
he really didn't describe at all what he did. He just gave you some numbers.
link |
Now, I just told you that you had to set this prism at a certain angle. You would think,
link |
because we do have his notes and so on, you would think that he took some kind of complicated
link |
measuring device to set the prism. He didn't. He held it in his hand. That's all. And he
link |
twiddled it around. And what was he doing? It turns out that when you twiddled the prism around,
link |
at the point where you should get a circle from a circle, it also is the place where the image
link |
does not move very fast. So if you want to get close to there, you just twiddle it. This is
link |
manipulative experimentation, taking advantage through his mathematical knowledge of the inherent
link |
inaccuracies that let you come to exact conclusions, regardless of the built in
link |
problematics of measurement. He's the only one I know of doing anything like that at this time.
link |
Well, even still, there's very few people that are able to have, to calculate as well as he did,
link |
to be a theoretician and an experimentalist in the same moment. Right? It's true, although until
link |
the, really, well into the 20th century, maybe the beginning of the 20th century, really,
link |
most of the most significant experimental results produced in the 1800s,
link |
which laid the foundations for light, electricity, electrodynamics, and so on, even
link |
hydrodynamics and whatnot, were also produced by people who were both excellent calculators,
link |
very talented mathematicians, and good with their hands experimentally.
link |
And then that led to the 21st century with Enrico Fermi, that one of the last people that
link |
was able to do that, both of those things very well, and that he built a little device
link |
called an atomic bomb that has some positives and negatives.
link |
Right. Of course, that actually did involve some pretty large scale elaborate equipment.
link |
Yeah. Well, holding a president in your hands, same thing.
link |
What's the controversy that Newton got into with that paper when he published it?
link |
Well, in a number of ways, it's a complicated story. There was a very talented character
link |
known as a mechanic. Mechanic means somebody who was a craftsman who could build and make
link |
really good stuff, and he was very talented. His name was Robert Hook, and he was the guy who,
link |
at the weekly meetings of the Royal Society in London, and Newton's not in London,
link |
you know, he's at Cambridge, he's a young guy, he would demonstrate new things,
link |
and he was very clever. And he had written a book, in fact, called The Micrographia,
link |
which, by the way, he used a microscope to make the first depictions of things like a fly's eye,
link |
the structure of, you know, and had a big influence. And in there, he also talked about light.
link |
And so he had a different view of light. And when he read what Newton was
link |
wrote, he had a double reaction. On the one hand, he said, anything in there that is correct,
link |
I already knew, and anything that I didn't already know is probably not right anyway.
link |
Got a love egos. Okay. Can we just step back? Can you say who was Isaac Newton?
link |
What are the things he contributed to this world in the space of ideas?
link |
Wow. Who was he? He was born in 1642, and near the small town of Grantham in England.
link |
In fact, the house he was born in, and that his mother died in, is still there and can be visited.
link |
His father died before he was born, and his mother eventually remarried a man named Reverend
link |
Smith, whom Newton did not like at all. Because Reverend Smith took his mother away
link |
to live with him a few miles away, leaving Newton to be brought up more or less by his
link |
grandmother over there. And he had huge resentment about that his whole life.
link |
I think that gives you a little inkling that a little bit of trauma in childhood,
link |
maybe a complicated father son relationship can be useful to create a good scientist.
link |
Could be, although this case, it would be right, the absent father,
link |
nonfather relationship, so to speak. He was known as a kid, little that we do know for
link |
being very clever about flying kites, and there are stories about him putting candles and putting
link |
flying kites and scaring the living devil out of people at night by doing that and
link |
things like that, making things. Most of the physicists and natural philosophers I've dealt
link |
with, actually, as children, were very fond of making and playing with things. I can't think of
link |
one I know of who wasn't actually. They were very good with their hands and whatnot.
link |
His mother wanted him to take over the manner. It was a kind of farming manner. They were
link |
the class of what are known as yeomans. There are stories that he wasn't very good at that.
link |
One day, one of the stories is he's sitting out in the field and the cows come home without him,
link |
and he doesn't know what's going on. Anyway, add relatives, and he manages to get to Cambridge,
link |
sent to Cambridge, because he's known to be smart. He's read books that he got from local
link |
dignitaries and some relatives. He goes there as what's known as a subsizer. What does that mean?
link |
Well, it's not too pleasant. Basically, a subsizer was a student who had to clean the bedpans of the
link |
richer kids. That didn't last too long. He makes his way and he becomes absorbed in some of the new
link |
ways of thinking that are being talked about on the parts of Descartes and others as well.
link |
There's also the traditional curriculum which he follows. We have his notes. We have his student
link |
notebooks and so on. We can see gradually this young man's mind focusing and coming to grips
link |
with deeper questions of the nature of the world and perception even, and how we know things,
link |
and also probing and learning mathematical structures to such an extent that he builds
link |
on some of the investigations that had been done in the period before him to create the foundations
link |
of a way of investigating processes that happen and change continuously, instead of
link |
by leaps and bounds and so on, forming the foundation of what we now call the calculus.
link |
Can you maybe just paint a little bit of a picture? You've already started of
link |
what were the things that bothered him the most that stood out to him the most about the traditional
link |
curriculum, about the way people saw the world. You mentioned discreet versus continuous. Is there
link |
something where he began thinking in a revolutionary way? Because it's fascinating. Most of us go to
link |
college, Cambridge or otherwise, and we just take what we hear as gospel, not gospel, but
link |
as facts. You don't begin to see how can I expand on this aggressively or how can I challenge
link |
everything that I hear rigorously, mathematically through the—I mean, I don't even know how
link |
rigorous the mathematics was at that point. I'm sure it was geometry and so on, no calculus, huh?
link |
There are elements of what turned into the calculus that predate Newton, but—
link |
How much rigor was there? How much—
link |
And then, of course, no scientific method, not really. I mean, appreciation of data.
link |
Ah, that is a separate question from a question of method. Appreciation of data is a significant
link |
question as to what you do with data. There's lots of things you're asking.
link |
I apologize. So maybe let's backtrack in the first question. Was there something that was
link |
bothering him that he especially thought he could contribute or work on?
link |
Well, of course, we can't go back and talk to him, but we do have these student notebooks.
link |
There's two of them. One's called the Philosophical Questions and the other is called the Waste Book.
link |
The Philosophical Questions has discussions of the nature of reality and
link |
various issues concerning it. And the Waste Book has things that have to do with motion
link |
in various ways, what happens in collisions and things of that sort.
link |
And it's a complicated story. But what's—among the things that I think are interesting is
link |
he took notes in the Philosophical Questions on stuff that was traditionally
link |
given to you in the curriculums going back several hundred years, namely on what scholars refer to
link |
as scholastic or neoscholastic ways of thinking about the world, dating back to the reformulation
link |
of Aristotle in the Middle Ages by Thomas Aquinas in the church. And this is a totally
link |
different way of thinking about things, which actually connects to something we were saying
link |
a moment ago. For instance, so I'm wearing a blue shirt and I will sometimes ask students,
link |
where is the blue? And they'll usually say, well, it's in your shirt. And then some of them get
link |
clear and they say, well, no, you know, light is striking. Photons are reemitted. They strike
link |
the back of your retina and et cetera, et cetera. And I said, yes. You—what that means is that the
link |
blue is actually an artifact of our perceptual system considered as the percept of blue. It's not
link |
out there, it's in here, right? That's not how things were thought about well into the 16th
link |
century. The general notion dating back even to Aristotelian antiquity and formalized by the
link |
12th century at the Paris, Oxford, and elsewhere is that qualities are there in the world.
link |
They're not in us. We have senses and our senses can be wrong. You know, you could get blind,
link |
things like that. But if they're working properly, you get the actual qualities of the world.
link |
Now, that break, which is occurring towards the end of the 16th century and is most visible in
link |
Descartes, is the break between conceiving that the qualities of the world are very different
link |
from the qualities that we perceive. That, in fact, the qualities of the world consist almost
link |
entirely in shapes of various kinds and maybe hard particles or whatever, but not colors,
link |
not sounds, not smells, not softness and hardness. They're not in the world. They're in us.
link |
That break, Newton is picking up as he reads Descartes. He's going to disagree with a lot in
link |
Descartes, but that break, he is, among other things, picking up very strongly. That underlies a lot
link |
of the way he works later on when he becomes skeptical of the evidence provided by the senses.
link |
Yeah, that's actually, I don't know, the way you're describing is so powerful,
link |
it just makes me realize how liberating that is as a scientist, as somebody who's trying to
link |
understand reality, that our senses are not to be trusted, that reality is to be investigated
link |
through tools that are beyond our senses. Yes. Or that improve our senses.
link |
Improve our senses, in some ways. That's pretty powerful. I mean, that is,
link |
for a human being, that's like Einstein level. For a human being to realize, I can't trust
link |
my own senses at that time. That's pretty trippy. It's coming in. It's coming in. I think it arises
link |
probably a fair number of decades before that, perhaps in part with all chemical experimentation
link |
and manipulations, that you have to go through elaborate structures to produce things and ways
link |
you think about it. But let me give you an example that I think you might find interesting because
link |
it involves that guy named Hook that Newton had an argument with. He had lots of arguments with
link |
Hook, although Hook was a very clever guy and gave him some things that stimulated him later.
link |
Anyway, Hook, who was argumentative, and he really was convinced that the only way to gain
link |
real knowledge of nature is through carefully constructed devices. He was an expert mechanic,
link |
if you will, at building such things. Now, there was a rather wealthy man
link |
in Danzig by the name of Hevelius, Latinized name. He was a brewer in town. He had become
link |
fascinated with the telescope. This is 30 years or so, 20 or 30 years after the telescope had moved
link |
out and become more common. He built a large observatory on the top of his brewery, actually,
link |
and working with his wife, they used these very elaborately constructed grass and metal
link |
instruments to make observations of positions of the stars. He published a whole new catalog of
link |
where the stars are. He claimed it was incredibly accurate. He claimed it was so accurate that
link |
nothing had ever come close to it. Hook reads this, and he says, wait a minute. You didn't use
link |
a telescope here of any kind because what's the point? Unless you do something to the telescope,
link |
all you see are dots with stars, you just use your eyes. Your eyes can't be that good. It's
link |
impossible. So, what did Hook do to prove this? He said, what you should have done is you should
link |
have put a little device in the telescope that lets you measure distances between these dots.
link |
You didn't do that, and because you didn't, there's no way you could have been that good.
link |
At two successive meetings of the Royal Society, he hauls the members out into the courtyard,
link |
and he takes a card, and he makes successive black and white stripes on the card,
link |
and he pastes the card up on a wall, and he takes them one by one. He says, now,
link |
move back, looking at it, presumably with one eye, until you can't tell the black ones from the
link |
white stripes. He says, that I can then measure the distance. I can see the angles. I can give a
link |
number then for what is the best possible, what we would call perceptual acuity of human vision.
link |
And it turned out, he thought, to be something like 10 or more times worse than this guy,
link |
Hevelius had claimed. So, obviously, he says, well, years ago, I calculated Hevelius's numbers and
link |
so on using modern tables from NASA and so on, and they are even more accurate than Hevelius
link |
claimed, and worse than that, the Royal Society sent a young astronomer named Halley over to
link |
Danzig to work with him, and Halley writes back, and he says, I couldn't believe it, but he taught
link |
me how to do it, and I could get just as good as he, how is it possible? Well, here, and this
link |
shows you something very interesting about experiments, perception, and everything else.
link |
Hooke was right, but he was also wrong. He was wrong for the right reasons, and he was right
link |
for the wrong reasons, and what do I mean by that? What he actually found was the number
link |
for what we now call 2020 vision. He was right. You can't tell, except a few people, much better
link |
than that. But he was observing the wrong thing. What Hevelius was observing was a bright dot,
link |
a star moving past a pointer. Our eyes are rather similar to frog's eyes. You know,
link |
I'm sure you've heard the story, if I hold a dead fly on a string in front of a frog and don't
link |
move it, the frog pays no attention. As soon as I move the fly, the frog immediately tongue
link |
latches out because the visual system of the frog responds to motion. So does ours, and our
link |
acuity for distinguishing motion from statics, five or more times better.
link |
Yeah, that's fascinating. Damn. Of course, maybe you can comment on their understanding
link |
of the human perceptual system at the time. It's probably really terrible.
link |
Like, yeah, like I've recently been working with just almost as a fun side thing with vision
link |
scientists and peripheral vision. It's a beautiful complex mess, that whole thing.
link |
We still don't understand all the weird ways that human perception works, and they were probably
link |
terrible at it. They probably didn't even have any conceptual peripheral vision or the fovea or
link |
I mean, basically anything. They had some, I mean, because actually it was Newton himself
link |
who probed a lot of this. For instance, Newton, the young Newton, trying to work his way around
link |
what's going on with colors, wanted to try and distinguish colors that occur through
link |
natural processes out there, and colors that are a result of our eyes not operating rights.
link |
You know what he did? It's a famous thing. He took a stick, and he stuck that stick under
link |
his lower eyelid and pushed up on his eyeball, and what that did would produce colored circles
link |
at diametrically opposite positions of the stick in the eyeball, and he moved it around to see
link |
how they moved, trying to distinguish. Legit. Right? I always have to tell my students, don't do this,
link |
but... Or do it if you want to be great and remembered by human history. There's a lot
link |
of equivalent to sticking to your eye in modern day that may pay off in the end. Okay.
link |
As a small aside, is the Newton and the Apple story true? No.
link |
No. Was it a different fruit? As a colleague of mine named Simon Schaffer in England
link |
once said on a NOVA program that we were both on, the role of fruit in the history of science has
link |
been vastly exaggerated. Okay. So was there any, I mean, to zoom out, moments of epiphany?
link |
Is there something to moments of epiphany? Again, this is the paradigm shift versus the
link |
gradualism. There is a shift. It's a much more complex one than that, and we...
link |
As it happens, a colleague of mine and I are writing a paper right now on one of the aspects
link |
of these things based on the work that many of our colleagues have done over the last 30 and 40 years.
link |
Let me try and see if I could put it to you this way. Newton, until the early 1670s,
link |
and probably really until a fair time after that, first of all, was not very interested in
link |
questions of motion. He was working actually in all chemical relationships, or what is called
link |
by historians, chymistry, a kind of early modern chemical structure. Colleagues of ours at Indiana
link |
have even reproduced the amalgams that... Anyway, his way of thinking about motion involved a certain
link |
set of relationships, which was not conducive to any application that would yield
link |
computationally direct results for things like planetary motions, which he wasn't terribly
link |
interested in anyway. He enters a correspondence with his original nemesis, Robert Hook, and
link |
Hook says, well, have you ever thought about, and then Hook tells him a certain way you might
link |
think about it, and when Newton hears that, he recognizes that there is a way to inject time
link |
that would enable him to solve certain problems. It's not that he... That there was anything he
link |
thought before that was contrary to that way of thinking. It's just that that particular
link |
technical insight was not something that, for a lot of reasons that are complex, had never occurred to
link |
him at all, and that sent him a different way of thinking. But to answer your question about the
link |
Apple business, which is always about gravity and the moon and all of that being... No. The
link |
reason there is that the idea that what goes on here in the neighborhood of the earth and what goes
link |
on at the moon, let us say, remind the sun and the planets, can be due to a direct relationship
link |
between the earth, let's say, and the moon is contrary to fundamental beliefs held by many of
link |
the mechanical philosophers, as they're called at the time, in which everything has to involve
link |
at least a sequence of direct contacts. It has to be something between here and there
link |
that's involved. And Hook, probably not thinking terribly deeply about it based on what he said,
link |
along with others like the architect and mathematician Christopher Wren,
link |
a harken back to the notion that, well, maybe there is a kind of magnetic relationship between the
link |
moon and maybe the planets and the earth and gravity and so on, vague, but establishing a
link |
direct connection somehow, however it's happening, forget about it. Newton wouldn't have cared about
link |
that, if that's all they said, but it was when Hook mentioned this different way of thinking about
link |
the motion, a way he could certainly have thought of because it does not contradict anything. Newton
link |
is a brilliant mathematician and he could see that you could suddenly start to do things with that,
link |
that you otherwise wouldn't connect. And this led eventually to another controversy with Hook,
link |
in which Hook said, well, after Newton published his great Principia, I gave him how to do this.
link |
And then Newton, of course, got ticked off about that and said, well, listen to this, I did everything
link |
and because he had a Picayune little idea, he thinks he can take credit for it.
link |
Okay. So his ability to play with these ideas mathematically is what solidified the initial
link |
intuition that you could have, was that the first time he was born the idea that you have
link |
action at a distance, that you can have forces without contact, which is another revolutionary
link |
idea. I would say that in the sense of dealing with the mechanics of force like effects,
link |
considered to act at some distance, it is novel with both Hook and Newton at the time,
link |
the notion that two things might interact at a distance with one another without direct contact,
link |
that goes back to antiquity. Only there it would thought of more as a sympathetic reaction
link |
to a magnet and a piece of iron. They have a kind of mutual sympathy for one another.
link |
Like what, love? What are we talking about? Well, actually, they do sometimes talk like that.
link |
That is love. See, now I talk like that all the time. I think love is somehow in consciousness
link |
or forces of physics that yet to be discovered. Okay. Now there's the other side of things,
link |
which is calculus that you began to talk about. So Newton brought a lot of things to this world.
link |
One of them is calculus. What is calculus? And what was Newton's role in bringing it
link |
to life? What was it like? What was the story of bringing calculus to this world?
link |
Well, since the publication starting many decades ago by Tom Whiteside, who's now deceased of
link |
Newton's mathematical papers, we know a lot about how he was pushing things and how he was
link |
developing things. It's a complex question to say what calculus is. Calculus is the set of
link |
mathematical techniques that enable you to investigate what we now call functions, mathematical
link |
functions, which are continuous. That is, that are not formed out of discrete sets like the
link |
counting numbers, for instance. Newton, there were already procedures for solving problems
link |
involving such things as finding areas to under curves and tangents to curves by using
link |
geometrical structures, but only for certain limited types of curves, if you will. Newton as
link |
a young man, we know this is what happened, is looking at a formula which involves an expansion
link |
in separate terms, polynomial terms, as we say, for certain functions. I know I don't want to get
link |
complicated here about this, but he realizes it could be generalized and he tries the generalization
link |
and that leads him to an expansion formula called the binomial theorem. That enables him to move
link |
ahead with the notion that if I take something that has a certain value and I add a little bit
link |
to it and I use this binomial theorem and expand things out, I can begin to do new things. The
link |
new things that he begins to do leads him to a recognition that the calculations of areas
link |
and the calculations of tangents to curves are reciprocal to one another. The procedures that
link |
he develops is a particular form of the calculus in which he considers small increments and then
link |
continuous flows and changes of curves and so on. We have relics of it in physics today,
link |
the notation in which you put a dot over a variable indicating the rate of change of the
link |
variable. That's Newton's original type of notation. Possibly independently of Newton
link |
because he didn't publish this thing, although he became quite well known as quite a brilliant
link |
young man in part because people heard about his work and so on. When another young man by the
link |
name of Gottfried Leibniz visited London and he heard about these things, it is said that he
link |
independently develops his form of the calculus, which is actually the form we use today,
link |
both in notation and perhaps in certain fundamental ways of thinking. It has remained a
link |
controversial point as to where exactly and how much independently Leibniz did it. Leibniz
link |
aficionados think and continue to maintain. He did it completely independently. Newton,
link |
when he became president of the Royal Society, put together a group to go on the attack saying,
link |
no, he must have taken everything. We don't know, but I will tell you this. About 25 or so years ago,
link |
a scholar who's a professor at Indiana now named Domenico Melly got his hands on a Leibniz manuscript
link |
called the Ten Taman, which was Leibniz's attempt to produce an alternative to Newton's mechanics.
link |
It comes to some conclusions that you have in the Newton's mechanics. Well, he published that,
link |
but Melly got the manuscript. What Melly found out was that Leibniz reverse engineered the
link |
Principia and cooked it backwards so that he could get the results he wanted.
link |
That was for the mechanics. That means his mind allows for that kind of thing.
link |
You're breaking some use today. Some people think so. I think most historians of mathematics
link |
do not agree with that. A friend of mine, a rather well known physicist, unfortunately,
link |
died a couple of years ago named Mike Nowenberg at UC Santa Cruz, had some evidence along those
link |
lines. Didn't pass mustard with many of my friends who are historians of math. In fact,
link |
I edit with a historian of math, a technical journal, and we were unable to publish it in
link |
there because we couldn't get it through any of our colleagues, but I remain suspicious.
link |
What is it about those tense relationships and that kind of drama? Einstein doesn't appear to
link |
have much of that drama. Nobody claims, I haven't heard claims that they've, perhaps because it's
link |
such crazy ideas of any of his major inventions, major ideas being those that are, basically,
link |
I came up with it first or independently. There's not, as far as I'm aware, not many people talk
link |
about general relativity, especially in those terms, but with Newton that was the case.
link |
Is that just a natural algorithm of how science works? Is there going to be personalities that,
link |
I'm not saying this about Linus, but maybe I am, that there's people who steal ideas for the,
link |
because of ego, because of all those kinds of things?
link |
I don't think it's all that common, frankly. The Newton hook, Leibniz, Contratomps, and so on.
link |
Well, you're at the beginnings of a lot of things there and so on. These are difficult and complex
link |
times as well. These are times in which science as an activity pursued by other than, let us say,
link |
interested aristocrats is becoming somewhat different. It's not a professional community
link |
of investigators in the same way. It's also a period in which procedures and rules are
link |
practiced or being developed to avoid attacking one another directly and pulling out a sword to
link |
cut off the other guy's head if he disagrees with you and so on. There's a very different period.
link |
Controversies happen. People get angry. I can think of a number of others,
link |
including in the development of optics in the 19th century and so on. It can get hot under the collar.
link |
Sometimes one character who's worked an area extensively, whether they've come up with
link |
something terribly novel or not, and somebody else moves in and does completely different
link |
novel things. The first guy gets upset about it because he's muscled into what I thought was my
link |
area. You find that sort of stuff. Do you have examples of cases where it worked out well,
link |
like that competition is good for the progress of science?
link |
Yeah. It almost always is good in that sense.
link |
It's just painful for the individuals involved.
link |
It can be. It doesn't have to be nasty, although sometimes it is.
link |
So on the space, for example, with optics, could you comment on that one?
link |
Well, yeah, sure. There are several, but I could give you...
link |
All right. So I'll give you this example that probably is the most pertinent.
link |
The first polytechnic school, like MIT or Caltech, was actually founded in France during
link |
the French Revolution. It exists today. It's the egg called polytechnique.
link |
All right. Two people who were there were two young men in the 90s, 1790s, named,
link |
on the one hand, François Aragot and the other Jean Baptiste Biot. They both lived a long time,
link |
well into the 1850s. Aragot became a major administrator of science, and Biot's career
link |
started to peter out after about the late teens. Now, they are sent on an expedition,
link |
which was one of the expeditions involving measuring things to start the metric system.
link |
There's a lot more to that story. Anyway, they come back. Aragot gets separated.
link |
He's captured by pirates, actually. Wounds up in Tangier, escapes, is captured again.
link |
Everybody thinks he's dead. He gets back to Paris, and so on. He's greeted as a hero,
link |
and whatnot. In the meantime, Biot has pretty much published some of the stuff that he's done.
link |
An Aragot doesn't get much credit for it. An Aragot starts to get very angry.
link |
Biot is known for this kind of thing. Aragot, anyway,
link |
Biot starts investigating a new phenomenon and optics involving something called polarization,
link |
and he writes all kinds of stuff on it. Aragot looks into this and decides to write some things
link |
as well. And actually, Biot gets mostly interested in it when he finds out that Aragot is doing stuff.
link |
Now, Biot is actually the better scientist in a lot of ways, but Aragot is furious about this.
link |
So furious that he actually demands and forces the leader of French science, Laplace,
link |
the Marquis de la Place, and cohorts to write a note in the published journal saying,
link |
oh, excuse us. Actually, Aragot, et cetera, et cetera, blah, blah. So Aragot continues
link |
to just hold this antipathy and fear of Biot. So what happens? 1815,
link |
Napoleon is finished at Waterloo. A young Frenchman by the name of Augustin Fresnel
link |
was in the army, is going back to his home on the north coast of France in Normandy. He passes
link |
through Paris. Aragot is friends with Fresnel's uncle, who's the head of the École des Beaux
link |
at the time. Anyway, Fresnel is already interested in certain things in light. And he talks to Aragot.
link |
Aragot tells him a few things. Fresnel goes home, and Fresnel is a brilliant experimenter.
link |
He observes things, and he's a very good mathematician, calculates things. He writes
link |
something up. He sends it to Aragot. Aragot looks at it, and Aragot says to himself,
link |
I can use this to get back at Beaux. He brings Fresnel to Paris, sets him up in a room at the
link |
observatory where Aragot is for Fresnel to continue his work paper after paper comes out,
link |
undercutting everything Beaux had done.
link |
What is it about jealousy and just envy that could be an engine of creativity
link |
and productivity versus an Einstein where it seems like not? I don't know which one is better.
link |
I guess it depends on the personality. Both are useful engines in science.
link |
Well, in this particular story, it's maybe even more interesting because Fresnel himself,
link |
the young guy, he knew what Aragot was doing with him, and he didn't like it. He wrote his
link |
brother said, I don't want to get an argument with Beaux. I just want to do my stuff. Aragot
link |
is using him, but it's because Aragot kept pushing him to go into certain areas that stuff kept coming
link |
out. Ego is beautiful. Back to Newton. There's a bunch of things I want to ask, but let's say
link |
since we're on the Leibniz and the topic of drama, let me ask another drama question. Why was
link |
Newton a complicated man? We're breaking news today. This is like... Right. Why was it complicated?
link |
His brain structure was different. I don't know why. He had a complicated young life, as we've said.
link |
He had always been very self contained and solitary. He had acquaintances and friends,
link |
and when he moved to London eventually, he had quite a career. A career, for instance,
link |
that led him when he was famous by then, the 1690s. He moves to London. He becomes first
link |
warden of the Mint. The Mint is what produces coins, and coinage was a complicated thing because
link |
there was counterfeiting going on. He becomes master of the Mint to the extent. A guy at MIT
link |
wrote a book about this a little bit. We wrote something on it too. I forget his name was Levin.
link |
That Newton sent investigators out to catch these guys and sent at least one of them,
link |
a famous one named Chalender, to the gallows. One of the reasons he probably was so
link |
particularly angry at Chalender was Chalender had apparently said some nasty things about Newton
link |
in front of Parliament at some point. Fair enough. Yeah. That was apparently not a good idea.
link |
Well, he had a bit of a temper, so he didn't have a bit of a temper. Clearly. Okay. Clearly.
link |
But he, even as a young man at Cambridge, though he doesn't come from wealth, he attracts
link |
people who recognize his smarts. There's a young fellow named Humphrey Newton.
link |
Shared his rooms. You know, these students always shared rooms with one another.
link |
Became his kind of eminuences to write down what Newton was doing and so on.
link |
And there were others over time who he befriended in various ways and so on. He was solitary.
link |
He had, as far as we know, no relationships with either women or men
link |
in anything other than a formal way. Those get in the way relationships.
link |
Right. Well, I mean, he was, I don't know if he was close to his mother. I mean,
link |
she passed away. Everything left him. He went to be with her after she died. He was close to
link |
his niece, Catherine Barton, who basically came to run his household
link |
when he moved to London and so on. And she married a man named Conduit, who became one of the
link |
people who controlled Newton's legacy later on and so on. And you can even see the house that
link |
the townhouse that Newton lived in in those days still there.
link |
All right. So there's the story of Newton coming up with quite a few ideas during a pandemic.
link |
We're on the outskirts of a pandemic ourselves. Right.
link |
And a lot of people use that example as motivation for everybody while they're in lockdown to get
link |
stuff done. So what's that about? Can you tell the story of that?
link |
Well, I can. Let me first say that, of course, we've been teaching over Zoom lately.
link |
There was no Zoom back then? There was no Zoom back then. Although,
link |
it wouldn't have made much difference because the story was Newton was so complicated in his
link |
lectures that at one point, Humphrey Newton actually said that he might as well have just
link |
been lecturing to the walls because nobody was there to listen to it. So what difference, but...
link |
Also not a great teacher, huh? If you look at his optical notes, if that's what he's reading from...
link |
Oh, boy. Okay. No. So what can you say about that whole journey through the pandemic
link |
that resulted in so much innovation in such a short amount of time?
link |
Well, I mean, there's two times that he goes home. Would he have been able to do it and do
link |
do it if he'd stayed at Cambridge? I think he would have. I don't think it really...
link |
Although, I do like to tell my advanced students when I lecture on the history of physics to the
link |
physics and chemistry students, especially we've been doing it over Zoom the last year,
link |
when we get to Newton and so on because these kids are 21, 22. I like to say, well, you know,
link |
when Newton was your age and he had to go home during an epidemic, do you know what he produced?
link |
So can you actually summarize this for people who don't know how old was Newton and what did
link |
he produce? Well, Newton goes up to Cambridge, as it said, when he's 18 years old, in the 1660.
link |
And the so called miraculous year, the Annus Mirabilis, where you get the development in
link |
the calculus and in optical discoveries especially, is 1666. Right? So he's what, 24 years old at the
link |
time, but judging from his, the notebooks that I mentioned, he's already, before that, come to
link |
an awful lot of developments over the previous couple of years. Doesn't have much to do with
link |
the fact that he twice went home. It is true that the optical experiments that we talked of a while
link |
ago with the light on the wall moving up and down, were done at home. In fact, you can visit the
link |
very room he did it in to this day. Yeah, it's very cool. And if you look through the window
link |
in that room, there is an apple tree out there in the garden. So you might be wrong about this.
link |
You're lying to me. Maybe there's an apple involved after all. Well, it's not the same
link |
apple tree, but it's cuttings. How do you know? They don't last that long, but it's 400 years ago.
link |
Oh, not this. Oh, wow. I continue with the dumbest questions. Okay. So you're saying that perhaps
link |
going home was not... It may have given him an opportunity to work things through. And after
link |
all, he did make use of that room and he could do things like put a, you know, a shade over the
link |
window, move things around, cut holes in it and do stuff. Probably in his rooms at Cambridge,
link |
he maybe not, although when he stayed at Cambridge, subsequently, he became a fellow.
link |
And then the first, actually the second Lucasian professor there, he was actually really the
link |
first one because Isaac Barrow, who was the mathematician, professor of optics, recognized
link |
Newton's genius, gave up what would have been his position because he recognized,
link |
not, Newton may not have learned too much from him, although they did interact. And so Newton was
link |
the first Lucasian professor, really, the one that Stephen Hawking held till he died. And we know
link |
that the rooms that he had there at Cambridge, subsequently, because rooms are still there,
link |
he built an all chemical furnace outside, did all sorts of stuff in those rooms.
link |
And don't forget, you didn't have to do too much as a Lucasian professor. Every so often,
link |
you had to go give these lectures, whether anybody was there or not, and deposit the notes
link |
for the future, which is how we have all those things.
link |
Oh, they were stored and now we have them and now we know just how terrible of a teacher Newton
link |
was. Yeah, but we know how brilliant these notes are. In fact, the second volume of Newton's
link |
of the notes, really, on the great book that he published, The Optics, which he published in
link |
1704, that has just been finished with full annotations and analysis by the greatest
link |
analyst of Newton's optics, Alan Shapiro, who retired a few years ago at the University of
link |
Minnesota and been working on Newton's optics ever since I knew him and before, and I've known him
link |
since 1976. Is there something you could say broadly about either that work on optics or
link |
print KPA itself as something that I've never actually looked at as a piece of work? Is it
link |
powerful in itself or is it just an important moment in history in terms of the amount of
link |
inventions that are within, the amount of ideas that are within, or is it a really powerful work
link |
in itself? Well, it is a powerful work in itself. You can see this guy coming to grips with and
link |
pushing through and working his way around complicated and difficult issues, melding
link |
experimental situations which nobody had worked with before, even discovering new things,
link |
trying to figure out ways of putting this together with mathematical structures,
link |
succeeding and failing at the same time, and we can see him doing that.
link |
I mean, what is contained within print KPA? I don't even know in terms of the scope
link |
of the work. All right. Is it the entirety of the body of work of Newton?
link |
No, no, no, no. The print KPA Mathematica. Is it calculus?
link |
Well, all right. So the print KPA is divided into three books.
link |
Excellent. Book one contains his version of the laws of motion and the application of those laws
link |
to figure out when a body moves in certain curves and is forced to move in those curves
link |
by forces directed to certain fixed points, what is the nature of the mathematical formula
link |
for those forces? That's all that book one is about, and it contains not the kind of version of the
link |
calculus that uses algebra of the sort that I was trying to explain before, but is done in terms of
link |
ratios between geometric line segments when one of the line segments goes very, very small.
link |
It's called the kind of limiting procedure, which is calculus, but it's a geometrically structured,
link |
although it's clearly got algebraic elements in it as well. And that makes the print KPA's
link |
mathematical structure rather hard for people who aren't studying it today to go back to.
link |
Book two contains his work on what we now call hydrostatics and a little bit about hydrodynamics,
link |
hydrodynamics, a fuller development of the concept of pressure, which is a complicated concept.
link |
And book three applies what he did in book one to the solar system. And it is successful
link |
partially, because the only way that you can exactly solve, the only types of problems you
link |
can exactly solve in terms of the interactions of two particles governed by gravitational force
link |
between them is for only two bodies. If there's more than two, let's say it's A, B, and C,
link |
A acts on B, B acts on C, C acts on A, you cannot solve it exactly. You have to develop techniques.
link |
The fullest sets of techniques are really only developed about 30 or 40 years after Newton's
link |
death by French mathematicians like Laplace. Newton tried to apply his structure to the
link |
sun, earth, moon, because the moon's motion is very complicated. The moon, for instance,
link |
exactly repeats its observable position among the stars only every 19 years.
link |
That is, if you look up where the moon is among the stars at certain times and it changes,
link |
it's complicated. That's, by the way, that was discovered by the Babylonians.
link |
That fact in 19 years.
link |
That was a few years ago, yes.
link |
And then you have to develop a piece of data and how do you make sense of it?
link |
Let me know. That is data and you have to fit in.
link |
And it's complicated. So Newton actually kind of reverse engineered a technique that had been
link |
developed by a man named Horrocks using certain laws of Kepler's to try and get around this thing.
link |
And Newton then sort of, my understanding, I've never studied this, has reversed it
link |
and fit it together with his force calculations by way of an approximation.
link |
And was able to construct a model to make some predictions?
link |
It fit things backwards pretty well.
link |
Okay. Where does data fit into this? We kind of earlier in the discussion
link |
mentioned data as part of the scientific method. How important was data to Newton?
link |
So like you mentioned Prisman playing with it and looking at stuff and then coming up
link |
with calculations and so on. Where does data fit into any of his ideas?
link |
All right. Well, let me say two things first. One, we rarely use the phrase scientific method
link |
anymore because there is no one easily describable such method. I mean, humans have been playing
link |
around with the world and learning how to repetitively do things and make things happen
link |
ever since humans became humans. Do you have a preferred definition of the scientific method?
link |
What are the various? No, I don't. I prefer to talk about
link |
the considered manipulation of artificial structures to produce results that can be
link |
worked together with schemes to construct other devices and make
link |
predictions, if you will, about the way such things will work.
link |
So ultimately, it's about producing other devices. It's like leads you down a...
link |
I think so, principally. I mean, you may have data, if you will, like astronomical data obtained
link |
otherwise and so on, but yes. But number two here is this question of data. What is data?
link |
In that sense, see, when we talk about data today, we have a kind of complex notion which
link |
reverts to even issues of statistics and measurement procedures and so on. So let me put it to you
link |
this way. So let's say I had a ruler in front of me. Go on. And it's marked off in little black marks
link |
separated by, let's say, distances called a millimeter. Now, I make a mark on this piece
link |
of paper here. So I made a nice black mark, right? Nice black mark. And I ask you, I want you to
link |
measure that and tell me how long it is. You're going to take the ruler, you're going to put it
link |
next to it, and you're going to look. And it's not going to sit, even if you put one in as close as
link |
you can on one black mark, the other end probably isn't going to be exactly on a black mark. Well,
link |
you'll say it's closer to this or that. You'll write down a number. And I say, okay, take the ruler
link |
away a minute. I take this away, come back in five minutes, put the piece of paper down, do it again.
link |
You're going to probably come up with a different number. And you're going to do that a lot of times.
link |
And then if I tell you, I want you to give me your best estimate of what the actual length of that
link |
thing is, what are you going to do? You're going to average all of these numbers? Why?
link |
Statistics. Well, yes, statistics. There's lots of ways of going around it. But the average is the
link |
best estimate on the basis of what's called the central limit theorem, a statistical theorem.
link |
We're talking about things that were not really developed until the 1750s, 60s, and 70s. Newton
link |
died in 1727. The intuition perhaps was there. Not really. I'll tell you what people did,
link |
including Newton, although Newton is partially the one exception. We talked a while ago about
link |
this guy, Christian Huygens. He measured lots of things. And he was a good mechanic himself.
link |
He and his brother ground lenses. Huygens, I told you, developed the first pendulum mechanism,
link |
pendulum driven clock with a mechanism and so on. Also a spring watch, where he got into a
link |
controversy with Hook over that, by the way. What's with these mechanics and the controversy?
link |
Well, we also have Huygens's notes. They're preserved at Leiden University in Holland.
link |
He's Dutch for his work in optics, which was extensive. We don't have time to go into that,
link |
except the following. A number of years ago, I went through those things, because in this
link |
optical theory that he had, there are four numbers that you've got to be able to get good numbers on
link |
to be able to predict other things. So what would we do today? What in fact was done at the end of
link |
the 18th century, when somebody went back to this? You do what you just, I told you to do with the
link |
ruler. You make a lot of measurements and average results. We have Huygens's notes. He did make
link |
a lot of measurements, one after the other after the other. But when he came to use the numbers
link |
for calculations, and indeed when he published things at the end of his life, he gives you one
link |
number, and it's not the average of any of them. It's just one of them. Which one was it? The one
link |
that he thought he got so good at working by practice that he put down the one he was most
link |
confident in. That was the general procedure at the time. You wouldn't publish a paper in which you
link |
wrote down six numbers and said, well, I measured this six times. Let me put them together.
link |
None of them is really, they would have said the right number, but I'll put them together
link |
and give you a good number. No, you would have been thought of that. You don't know what you're
link |
doing. Yeah. By the way, there's just an inkling of value to that approach. Just an inkling. We
link |
sometimes use statistics as like a thing that like, oh, that solves all the problems. We'll
link |
just do a lot of it and we'll take the average or whatever it is as many excellent books on
link |
mathematics have highlighted the flaws in our approach to certain sciences that rely heavily
link |
on statistics. Let me ask you again for a friend about this alchemy thing. It'd be nice to create
link |
gold, but it also seems to come into play quite a bit throughout the history of science,
link |
perhaps in positive ways in terms of its impact. Can you say something to the history of alchemy?
link |
A little bit. Sure. It used to be thought two things. One, that alchemy, which dates certainly
link |
back to the Islamic period in Islam, you're talking 11th, 12th, 13th centuries among Islamic
link |
natural philosophers and experimenters, but it used to be thought that alchemy, which picked up
link |
strikingly in the 15th, 16th century, 1500s and thereabouts, was a sort of mystical procedure
link |
involving all sorts of strange notions and so on. That's not entirely untrue,
link |
but it is substantially untrue in that all chemists were engaged in what was known as
link |
Chrisl Poyer. That is looking for ways to transform invaluable materials into valuable ones,
link |
but in the process of doing so or attempting to do so, they learned how to create complex
link |
amalgams of various kinds. They used very elaborate apparatus, glass olympics in which they would
link |
use heat to produce chemical decompositions. They would write down and observe these compositions
link |
and many of the so called really strange looking alchemical formulas and statements where they'll
link |
say something like, I can't produce it, but it'll be built. The soul of Mars will combine with the
link |
this, etc., etc. It has been shown are almost all actual formulas for how to engage in the
link |
production of complex amalgams and what to do. By the time of Newton, Newton was reading the works
link |
of a fellow by the name of Starkey, who actually came from Harvard shortly before,
link |
in which things had progressed, if you will, to the point where the procedure turns into what
link |
historians call Chrisl Poyer, which basically runs into the notion of thinking that these
link |
things are made out of particles. This is the mechanical philosophy. Can we engage in processes,
link |
chemical processes, to rearrange these things, which is not so stupid after all. We do it,
link |
except we happen to do it in reactors, not in chemical processes, unless, of course,
link |
it had happened that cold fusion had worked, which it didn't.
link |
That's the way they're thinking about these things. There's a kind of mix. Newton engages
link |
extensively in those sorts of manipulations. In fact, more in that than almost anything else,
link |
except for his optical investigations, if you look through the latter parts of the 1670s,
link |
the last five, six, seven years or so of that, there's more on that than there is on anything
link |
else. He's not working on mechanics. He's pretty much gone pretty far in optics. He'll turn back
link |
to optics later on. Optics and alchemy. What you're saying is Isaac Newton liked shiny things.
link |
Actually, if you go online and look at what Bill Newman, the professor at Bloomington,
link |
Indiana has produced, you'll find the very shiny thing called the Star Regulus, which
link |
Newton describes as having produced according to a particular way, which Newman figured out and
link |
was able to do it. It's very shiny. There you go. Proves the theorem. Can I ask you about God,
link |
religion, and its role in Newton's life? Was there helpful, constructive, or destructive
link |
influences of religion in his work and in his life? Well, there you begin to touch on a complex
link |
question. The role that God played would be an interesting question to answer. Should one go
link |
and be able to speak with this invisible character who doesn't exist, but putting that aside for
link |
the moment? Yeah, we don't like to talk about others while they're not here.
link |
Newton is a deeply religious man, not unusually so, of course, with assignment.
link |
Clearly, his upbringing and perhaps his early experiences have exacerbated that in a number
link |
of ways, that he takes a lot of things personally, and he finds perhaps solace in thinking about
link |
a sort of governing, abstract, rulemaking, exacting deity. I think there is little question
link |
that his conviction that you can figure things out has a fair bit to do with his
link |
profound belief that this rulemaker doesn't do things arbitrarily. Newton does not think that
link |
miracles have happened since maybe the time of Christ, if then, and not in the same way. He was,
link |
for instance, an anti Trinitarian. He did not hold that Christ had a divine being,
link |
but was rather endowed with certain powers by the rulemaker and whatnot. He did not think that some
link |
of the tales of the Old Testament with various miracles and so on occurred in anything like that
link |
way. Some may have, some may not have. Like everybody else, of course, he did think that creation
link |
had happened about 6,000 years ago. Wait, really? Oh, yeah, sure. Well, biblical chronology can give
link |
you a little bit about that. It's a little controversial, but sure. Interesting. Wow.
link |
The deity created the universe 6,000 years ago. That didn't interfere with his playing around with
link |
the sun and the moon and the network. Oh, no, because he's figuring out, he's watching
link |
the brilliant construction that this perfect entity did 6,000 years ago. Yeah, has produced.
link |
Buster minus a few years. Well, if you go with Bishop Buster, it's 4,004 BCE.
link |
Want to be precise about it. We always, this is a serious program. We always want to be precise.
link |
Okay, let me ask another ridiculous question. If Newton were to travel forward in time
link |
and visit with Einstein and have a discussion about space time and general relativity, that
link |
conception of time and that conception of gravity, what do you think that discussion will go like?
link |
Put that way, I think Newton would sit there and shock and say, I have no idea what you're
link |
talking about. If, on the other hand, there's a time machine, you go back and bring a somewhat
link |
younger Newton, not a man my age, say. I mean, he lived a long time into his mid 80s,
link |
but take him when he's in his 40s, let's say. Bring him forward and don't immediately introduce
link |
him to Einstein. Let's take him for a ride on a railroad. Let him experience the railroad.
link |
Oh, that's right. Take him around and show him a sparking machine. He knows about sparks,
link |
sending off sparks. Show him wires, have him touch the wires and get a little shock.
link |
Show him a clicking telegraph machine of the kind. Then let him hear the clicks in a telephone
link |
receiver and so on. Do that for a couple of months. Let him get accustomed to things.
link |
Then take him into, not Einstein yet, let's say we're taking him into the 1890s. Einstein is a
link |
young man then. We take him into some of the laboratories. We show him some of the equipment,
link |
the devices, not the most elaborate ones. We show him certain things. We educate him
link |
bit by bit. The optics, maybe focus on that. Certainly on optics. You begin to show him things.
link |
He's a brilliant human being. I think bit by bit, he would begin to see what's going on.
link |
But if you just dumped him in front of Einstein, he'd sit there as eyes would glaze over.
link |
I mean, I guess it's almost a question of how big of a leap, how many leaps have been taken
link |
in science that go from Newton to Einstein? We sometimes in a compressed version of history
link |
think that not much. Oh, that's totally wrong. A lot. Huge amounts in multifarious ways,
link |
involving fundamental conceptions, mathematical structures, the evolution of novel experimentation
link |
and devices, the organization. It's not everything. Everything. I mean, to a point where I wonder,
link |
even if Newton was like, you said 40, but even like 30, so he's very, like if you would be able
link |
to catch up with the conception of everything. I wonder as a scientist, how much you load in from
link |
age five about this world in order to be able to conceive of the world of ideas that push
link |
that science forward. I mean, you mentioned the railroad and all those kinds of things.
link |
That might be fundamental to our ability to invent even when it doesn't directly
link |
obviously seem relevant. Well, yes. I mean, the railroad, the steam engine, the watt engine,
link |
et cetera. I mean, that was really the watt engine was developed pretty although what
link |
knew Joseph Black, a chemist, scientist, and so on, did stuff on heat, was developed pretty
link |
much independently of the developing thoughts about heat at the time. But what it's not independent of
link |
is the evolution of practice in the manufacture and construction of devices,
link |
which can do things in extraordinarily novel ways and the premium being gradually placed
link |
on calculating how you can make them more efficient. That is of a piece with a way of
link |
thinking about the world in which you're controlling things and working. It's something that humans
link |
have been doing for a long time, but in this more concerted and structured way, I think you really
link |
don't find it in the fullest sense until well into the 1500s and really not fully until the
link |
17th century later on. Newton had this year of miracles. I wonder if I could ask you briefly
link |
about Einstein and his year of miracles. I've been rereading, revisiting the brilliance of
link |
the papers that Einstein published in the year 1905, one of which one of the Nobel Prize,
link |
the photoelectric effect, but also Brownian motion, special theory of relativity, and of
link |
course the old E equals MC squared. Does that make sense to you that these two figures had such
link |
productive years that there's this moment of genius? Maybe if we zoom out, my work is very
link |
much in artificial intelligence, wondering about the nature of intelligence. How did evolution
link |
on earth produce genius that could come up with so much in so little time? To me, that gives me hope
link |
that one person can change the world in such a small amount of time.
link |
Well, of course, there are precedents in both Newton's and Einstein's cases for elements of
link |
what we're finding there and so on. Well, I have no idea. You know, I'm sure you must have read,
link |
it was a kind of a famous story that after Einstein died, he donated his brain and they sliced it up
link |
to see if they could find something unusual there, nothing unusual visibly in there. Clearly,
link |
there are people who for various reasons, maybe both intrinsic and extrinsic in the sense of
link |
experience and so on, are capable of coming up with these extraordinary results. Many years ago,
link |
when I was a student, a friend of mine came in and said, did you read about? Did you read this?
link |
I forget. Anyway, there was a story in the paper. It was about, I think it was a young woman who
link |
was, she couldn't speak and she was somewhere on the autism spectrum. She could not
link |
read other people's affect, in any ways, but she could sit down at a piano and having heard it once
link |
and then run variations on the most complex, pianistic works of Chopin and others. Right. Now, how?
link |
Some aspect of our mind is able to tune in some aspect of reality and become a master of it.
link |
And every once in a while, that means coming up with breakthrough ideas in physics. Yep. How
link |
the heck does that happen? Who knows? Jed, I'd like to say thank you so much for spending your
link |
valuable time with me today. It was a really fascinating conversation. I've learned so much
link |
about Isaac Newton, who's one of the most fascinating figures in human history. So thank you so much
link |
for talking to me. A pleasure. I enjoyed it very much. Thanks for listening to this conversation
link |
with Jed Buchwald. To support this podcast, please check out our sponsors in the description.
link |
And now, let me leave you with some words from Thomas Kuhn, a philosopher of science.
link |
The answers you get depend on the questions you ask. Thank you for listening and hope to see you