This is the last class until very near the end of the next semester where I have this broad focus instead of looking almost proposition by proposition. I'll talk about next week, after break, because what we'll be doing next week really is the beginning of the Principia. Tonight what I'm doing is introducing you to Newton and giving you a broad picture of what he was like.
In the first few minutes, I'll cover more or less his whole life for a brief time. Then I will focus on what he did between the time he entered Cambridge University in 1662, I guess it is. And 1679, when Hook initiates a brief correspondence with him that ultimately led to the Principia.
Though not right away as you'll see next week. But all that, starting next week we'll focus on the development of the Principia starts in 1679. So this the house in which Newton was born on Christmas Day, 1642 by the old calendar, the Julian calendar which at that time I think was 12 or 13 days different from the Gregorian calendar.
England didn’t switch over to the Gregorian calendar, to well into the 18th century. I’ve showed the picture, I’ve never been there, there is an apple tree there. And that's been greatly nurtured ever since. It is a sort of museum now. I lifted this picture out of a exhibition from the 1950s.
Which reminds me, both the notes and the appendix got updated today. The notes because I found the source for this picture is the sole change. The point I'm making with it is, Newton was not poor. He was never financially badly off, because his father owned this farm. His father died before he was born.
His father died two or three months before he was born. But the house, if you go back to 1642, this is not poverty. This is a rather nice house. And they had a full farm. And that meant they were land owners and there weren't that many people in Britain at the time who owned land.
This was a different era. So he was never really financially threatened. I'm gonna run through this. There are all sorts of chronologies of Newton's life. This is the best as far as I'm concerned. Rupert Hall did it, and it comes from this biography. This is probably the best straight biography that doesn't concentrate on, it's not an intellectual biography.
The best intellectual biography by far, I'll pass both of these around, is Sam Westfall's, Never at Rest. This is a paperback version of it. The only fault in this book, and boy I'm really being picky is Sam chose on too many occasions to take a position about when something happened or what occurred in a conversation for which the evidence is inadequate.
Now it's one thing to do that in conversation even in a classroom like this, it's another to do that in print. Because he sometimes gives more of an impression that we know more about the details of Newton's life than we actually know. We know surprisingly little. And that's one of the great things about this chronology.
So his mother, Hannah, married in April 1642, and he was born in December. His father could neither read nor write. She could, she was literate. She remarried in 1646 to a Barnabus Smith. At which point she moved away from Woolsthorpe, leaving three-year-old Newton in the hands of his maternal grandmother, who also could read or write.
She was literate that why his mother was literate, as his grandmother was literate. And again literacy was not commonplace in all of England at the time. Witness where unto was his father was not literate. So you picture this three-year-old handed to his grandparents, mother goes away. Seven years later, his mother returns with two half sisters and no husband anymore.
She's been widowed for the second time. So as a ten-year-old boy, he gets to be joined by two other children. I'm not sure that's the happiest way somebody lives from three to ten. With grandmother, with mother away and fairly properly there after, two years later he sent off to boarding school.
Where he stays. The principal thing said about him from his days in the Grantham school which is not. By the way, I should have told you Woolsthorpe is Northwest of Cambridge by I guess about 100 miles on the way up toward Leeds, but north of Cambridge in Lincolnshire.
I like to say about Newton, but when I looked at the map of Lincolnshire over the weekend just to see exactly where Woolsthorpe is, that Newton lived in England but never saw the ocean. Or the sound. That's a fairly remarkable claim to make to live on an island and never see it.
But I'm now dubious because it's about a one day trip from Woolsthorpe to the North Sea. But there's no report of his ever seeing the ocean. At any rate he went off to Grantham school and the one thing we know about him there is he had a knack for creating toys, especially mechanical toys, for the other boys.
But there was nothing distinctive about him as a boarding school student. He graduates from there, comes home and they thought what did they expect? They handed him over the farm and said now you run the farm. And after one year, Hannah, his mother, and her brother decided this is a mistake.
He's not cut out to run farms and her brother had gone to Cambridge, so pressed upon her maybe he should go to Cambridge. So they decided to send him back to Grantham to prepare to go to Cambridge. And he find them wrong. He matriculated in 1661, not 1662.
As a Caesar, a Trinity College. First of all, Cambridge consisted of separate colleges, as I trust you all know. Trinity's famous for many reasons, one of them is Newton and the other is Maxwell. Just to comment on the two most physicists in the history of Britain both having gone to the same college.
But them Bertrand Russell went there too. I could name a lot of other Trinity fellows. I'm sorry how did I do that. Being a Ceasar Mech that you waited on the fellows. You did odds and ends for the fellows. You waited tables, etc. And it's a comment that they didn't have so much money that they just threw them into college.
By 1664, he had impressed at least somebody within Trinity College that he was no longer a caesar mech, he was made a scholar which meant he had some money. He no longer had to work to have basic living while in college. It's in 1663 that he starts getting serious about things like mathematics.
As it says here, mathematical and scientific notes. He graduated in 1665. If you say he started in 1663, and he graduated in January 1665, what I like to say about him is in an 18 month period ending in May 1665. He went from a novice in mathematics knowing nothing more than a Grantham School and starting to read, to being the world's leading mathematician.
He was ahead of everybody else 18 months later. And that's fairly impressive. We'll see some of how he did it in a couple moments. But people at Cambridge, in particular Isaac Barrow the professor of Mathematics and his first newcasian professor of Mathematics at Trinity College, actually at Cambridge.
Newton was the second to name, what's his name, I'm drawing a blank. The person who has Lou Gehrig's disease. Hawking is the current Lucasian professor unless he's retired. There's been a list of very spectacular people in that position but we'll get to that in a moment. So he graduated in 1665.
The plague hit England at that time which meant Cambridge University was closed. He was home for a period. The year 1665 through 1666 is generally referred to as Newton's annus mirabilis because he basically came through with the first full exposition of the calculus. He did a number of breakthroughs in optics, he did various other things I'll be discussing.
He goes back to Cambridge, then the plague breaks out again, which sends him back home again. So this period, 1665 to roughly 1667 when he returns to Cambridge. That's a period of enormous productivity when he's approximately 25 years old. We don't know a lot about what happened there.
It's almost all anecdotal or his own notebooks and things like that. Newton had the unfortunate tendency not to date things he wrote. So we have thousands and thousands of pages with very few dates on things. On theology, on chemistry, on astronomy, in mathematics. His mathematical papers unpublished Tom Whiteside collected in a feat of accomplishments that still awes me, Tom died just three or four years ago.
This is one of eight volumes like this that he produced and most of it is Newton, facing pages Latin and English. But there are, almost as many footnotes and small print, almost as many words that way in those volumes. As there are texts from Newton. And it's Whiteside's having done that that really has made Newton's technical work available in a manner that it wouldn't simply be otherwise.
I'm gonna regale you with anecdotes about Tom Whiteside, but there are a lot to tell. His mentor and person he admired, well let's go back, in 1668 Mercator published his book on logarithms and that finally pushed Newton to thinking Mercator was gonna beat him to all the results he already had, he wrote a tract called De Analysi.
The analysis of infinite equations in English. And sent it off actually carried by Isaac Barrow to John Collins in London. And John Collins made copies of it and it circulated and very quickly within the in group Newton was recognized. Barrow had already recognized him Recognized as a really major mathematician still well under 30-years-old at the time.
It was that tract that when Leibniz visited John Collins in the 1670s, he saw that tract. And that's part of the controversy over whether, what Leibniz got from seeing that tract. The view now is very little. But at the time, there was no way to recognize that. And that made the priority dispute really nasty.
As you can see, Barrow resigned in 1669 the Lucasian Professorship because he didn't want to do math anymore. He wanted to focus on theology. And he recommended the 27-year-old Newton to replace him in the Lucatian professorship. So Newton sort of went rather quickly from a BA to being a fellow but not a fully registered fellow to having one of the most highly endowed full professorships in all of England.
Still in his 20s without publishing a thing, I might add, so much for that. His first publications come in 1671, the sequence is fairly striking, Barrow carried his reflecting telescope to London. People started looking at it, he got encouraged to publish, to send in and they came in in the form of letters that were published in fill transaction.
Two initial letters, one describing his results on optics, on refraction that I'll cover in a few minutes, and then the second on the telescope. That led to a very intense series of, letters in opposition. They came from a French priest, I guess. Pardes, from Hook, and from Huygens.
Huygens is a lot more polite than Hook and Pardes. Both Hook and Pardes, well everybody had great trouble reproducing Newton's experimental results. And it's fairly typical of Newton's life. He made very, very clear in the first paper you need a very, very dark room with a very small aperture for light getting into it.
And of course nobody did that and as a result light being dispersed off the walls etc killed the effect. But Hook finally reproduced it when it was made clear enough to him that it wasn't a trivial experiment to do. The controversy centered on, particularly from Huygens and Hook both of whom were recommending a wave theory of light that Newton seemed to be committed to a particle theory of light.
And no matter how many times Newton said no, I do not consider the particle account of light as established. I'm simply using talk of particles as a way of describing rays as a trace of a particle but the experimental results in no way whatsoever depend on, nor do they give evidence for a particle theory of light.
No matter how many times he said that, They kept thinking, he hasn't shown with his experiments that the particle theory of light is true. And so it led to enough of a controversy, that by 1675 he gets mad enough to show that his results can be derived both from wave theory and particle theory.
And then sort of announces, I'm through with philosophy. It's much too contentious. I want no part of this. And has no further publications in any area of philosophy publications before the Principia when he's 44 years old. So he just drops out at that time. Now this is all spelled out in here building up to the 1675.
The last paper and hypothesis explaining the properties of light is the one that shows if it's derivable from waves as well. At this time and until 1696 and Newton from time to time, this is when he started doing chemistry and also started into Theology. But he essentially just drops out.
Of being in the public at this time, he just becomes a professor of math doing various research on his own. About which we know remarkably little on the whole. Work's being done on his chemical experiments. He did hundreds of very carefully done chemical experiments, chemical and alchemical on which he had terrible trouble reproducing the results.