Welcome back to Season Three of The HPS Podcast, where we discuss all things history, philosophy, and social studies of science in an accessible way. I am Samara Greenwood and today I am talking with Dr Kirsten Walsh, a philosophy lecturer at the University of Exeter. Kirsten’s research primarily focuses on Isaac Newton’s methodology, but she is careful to always consider philosophical issues with a sensitivity and consideration for historical contexts.
In today’s episode Kirsten gives us a sense of how historical and philosophical understanding of Newton has changed over time, and the role various archival practices play in what knowledge is developed. Kirsten’s lively discussion gives us a wonderful insight into the detailed, everyday practices of Newton, but also of the archivists who decide what is to be kept, and the historians who interrogate those documents in varying ways.
Samara Greenwood: Now starting off in our usual style, how did you find your way to history and philosophy of science?
Kirsten Walsh: Well, I sort of stumbled into HPS. I was looking through a course catalogue with my dad figuring out what courses I was going to take and there was a course that just sounded really interesting. I took it as something fun alongside politics and psychology and all those sensible things. I was hooked on it from that first course. So, I ended up with a major in HPS at Melbourne Uni and went on and did honours in HPS.
What was weird was that while I did that, I always identified as a philosopher. I always thought that philosophy of science was the thing that I was really interested in. I did a master's at Melbourne Uni in HPS. But it was very much a philosophy of science masters.
It was near the end of that, that I started to become really aware that the kinds of case studies that philosophers of science use, the historical case studies, were really just toy cases. That a lot of the time the philosophers were just wrong about the history in these really interesting ways and ways that mattered for the kind of philosophy that they were doing. I started to realize that I was really interested in finding out what the history really was like to see if this would make a difference to philosophers’ understandings of how science works.
I didn't really have the concept of scientific practice at the time. It turns out that philosophers of science in Australia have been interested in philosophy of science in practice for a really long time, it's just that we never really called it that. We didn't realise that that's what it was. It was only when I came over to Britain that I realised that, oh, this is the thing that we've been doing all this time.
Then Peter Anstey, who was then at the University of Otago, was advertising for PhD students on his new project on early modern experimental philosophy. That seemed like a really good way into some of these issues and so I ended up doing a quite historically focused PhD on Newton's methodology. It was kind of surprising, I didn't see myself as someone interested in the historical stuff until quite late.
Samara Greenwood: Today you are talking to us about your work on Isaac Newton and how science historians’ study well known figures from the past. Now, many of our listeners probably have a fairly traditional understanding of Newton and Newton's role in the history of science. So, I was wondering if you could begin by telling us a little bit about how contemporary historians view Newton's role in the history of science.
Kirsten Walsh: Historians of the past have focused on these big figures. I mean, Newton is probably one of the biggest. We see the history of science as though it's a seamless trajectory from the past to the present punctuated by these big important men or these big important ideas that everybody just glommed onto and agreed were good.
But contemporary historians view Newton and the history of science a bit differently to that, where no one really disputes Newton's importance to the history of science. No one disputes the fact that the Principia was a really important book. This was a landmark in the history of celestial mechanics. But they recognize it much more as one of many kinds of achievements that were happening at the time. It turns out that that period in early modern science was just important. There was a lot going on.
I think people are much better at seeing Newton not just as this solitary genius, but as somebody who had colleagues and had people who he was talking to, who were involved in some of his research, who he was feeding off learning things from.
They also recognize that Newton was part of a movement. He was involved with the early Royal Society. He chose to explicitly identify as somebody who was using the methods of the early Royal Society. He was the president of the Royal Society. The Royal Society itself was this practically focused collaborative group of early modern scientists who approached science in a very kind of embodied way. They were very interested in carrying out experiments and doing things and seeing things for themselves, and Newton was really no different. He did his own experiments and dabbled in lots of different things.
Often when you're looking at the minutes of early Royal Society meetings, Newton has all sorts of interesting things to say in those meetings about stuff that we don't really think of as being in his wheelhouse, about experiments he'd done on animals and things like this. So, you get this sense of this person who's very much a product of his day. He's very much doing the kind of work that all the other natural philosophers around him are doing, as well as writing these landmark books.
Also, contemporary historians recognise Newton's scientific work as being just one of a large number of different scholarly activities that Newton was involved in. In fact, we have realised that traditional science was not really as central or significant to Newton's research profile as has been traditionally thought. When you start to look at all the different kinds of writings that are now available of Newton's, his alchemical work, his theology, his church history were clearly really important research interests for him as well.
That helps you to start putting a lot of his scientific research in a much broader context. You get a sense more about the kind of work he was really interested in doing, which was really trying to learn about God. He was really trying to figure out what our relationship should be with God and what our place in the universe is, given God's place in the universe.
Samara Greenwood: I understand your current work involves thinking about how we study historical figures like Newton, including archival practices and digital humanities, could you tell us about your work in this area?
Kirsten Walsh: I've been getting interested in the philosophy of history lately. This is a relatively new area in philosophy and honestly, I feel like those who have written on philosophy of history so far haven't quite captured, I think, what's important about historical practice.
Philosophers, because they're philosophers, tend to be interested in metaphysical and epistemological questions because this is what we're trained to do. Philosophers of history tend to want to talk about things like the ontological status of past events. So, they want to talk about things like, did World War Two actually happen or is this something we constructed after the fact once we put a label on that series of events? Important questions, but they tend to talk as though historians are the ones who are primarily responsible for doing history or for creating historical narratives. I think this overlooks the importance of all the people who are responsible for creating historical traces, in this case historical records, producing and putting together archives and things like that.
So, I got interested in what it takes to produce an archive, to create it. All of the people that needed to create records to begin with, and then decide to keep those records, as opposed to burning them or throwing them out or losing them, and then deciding to preserve them so that they would survive down through the generations. Then someone needs to curate these collections and put them into some sort of order such that you can find what you're looking for. There's this whole decision-making process that has occurred before historians even get their hands on any of this material. That's the thing that I've become interested in, archival practices and the role of archival practices in shaping the history of science.
Newton makes an interesting case study for this because of the really surprising, interesting journey that his papers went on. Sarah Dry wrote a book a few years ago that well documents what happened with these papers. I won't go into too much detail on that but, the basic idea is that after Newton's death, his niece and, and her husband did a good PR job on Newton. During his lifetime, he had written a lot of theological manuscripts that were quite heretical in a lot of ways. What Newton's niece and her husband did was to lock down these papers to make sure that they wouldn't get disseminated, that no one would find out about this part of his life. What they did was put out this story, this ideal of Newton as this rational, clever, cold, calculating scientist and it was effective. People just accepted this. It created this notion of Newton as the archetypal scientist, this secular genius.
They also kept all his manuscripts and hid them away. Eventually those ended up in the hands of the Portsmouth family who, in the 1830s I think, decided to hand over to the Cambridge University Library all of the ones that were on Newton's scientific work. They formed a council, and over the next 20 years or so, they went through all the papers and just kept the ones that were relating to his celestial mechanics, his optics, his mathematics and handed back all of the others as being of ‘no intellectual value’.
So, those papers sat with the Portsmouth family for another nearly one hundred years until they decided to auction them off in the early 20th century. This was a really well marketed auction, but no institutional buyers showed up. This was because everyone had bought into the idea that there was the clever, rational, sane Newton who did all the scientific work. Then there was the crazy old Newton who did all the alchemy and theology and church history and so on.
These papers got picked up by individuals and got scattered. Luckily there were two guys who recognised the value of these papers: Keynes and Yehuda. Keynes bought up as many of the alchemical papers as he could, and Yehuda bought up as many of the theology and church history manuscripts as he could. There was a lot of scrambling around after the fact to see if they could buy things from people who picked them up at the auction and both ended up with pretty good collections of papers. Keynes' have ended up at Oxford University now, and Yehuda’s have ended up at the Hebrew University in Jerusalem.
So, it's been very difficult to look at all these documents because they're in such different locations and you don't put them all together. But, in the last couple of decades, Scott Mandelbrote is in Cambridge and Rob Iliffe is now in Oxford, and they've been working really hard to produce The Newton Project, which is a digital collection of all of Newton's papers.
This has been a huge project. It has required huge numbers of man hours and human resources to get this thing to work but It's an excellent resource. Once you can see that they're all in one place, things look very different. You get a very different perspective on what Newton's life and his work was really all about. You recognise that there's much more overlap between these things than anyone had really recognised. That's one of the things that's interesting about this. Looking at archives and looking at the kind of decisions that get made.
I've also been looking at a contrast case, which is the archives of the Royal Society. They adopted experimental philosophy as their main methodology and a huge part of experimental philosophy is gathering facts, making observations, and keeping notes and records. Making sure that you've got tables of all your results and gathering facts and evidence from as far afield as you can and then bringing it all back and putting it all together.
So, the early Royal Society created this archive. I don't think they were prepared for how huge this was. There's a lot of early discussions about needing to bring on extra secretaries. One of the things that happened very quickly was that they didn't have the space to keep all these documents. So, they are scattered around people's houses. It was very messy and difficult and there's lots of challenges involved. It makes it very difficult to find documents when you need them. And, if too many people know that the documents are not where they should be, then people start to kind of lose faith in your organization's archive. People are less likely to send you their material because well, you're just going to lose it. So, then they send it to other places. It's interesting, I think, to look at how this archive formed and these challenges that it faced and how all this is reinforced by this ideology they had about the importance of keeping all these records.
I've been looking at those two cases as very different kinds of cases. Nevertheless, there's these ideas about what good scientific practice look like that inform how these archives are constructed.
Samara Greenwood: Has that changed over time? Has [the Royal Society archive] been digitised and revisited in different ways?
Kirsten Walsh: Only small bits of it have been digitised, but it has definitely been visited and revisited over the years. The most obvious signs of this are evidence of different numbering systems having happened over time and the documents being put into different orders and included among different collections.
Because the Royal Society kept minutes of all its meetings, I've also looked at the minutes for committees that were set up in the 19th and the 20th century to figure out what to do with the archive and with the library because this is an issue that's been going on for hundreds of years. They've never had enough space for this archive because it's so big and it's always been a problem to keep track of all the documents they have, and because people are sending them new stuff all the time as well.
Every couple of decades they set up a committee to figure out what to do with the library and archive. They have different approaches at different times. There was a point in the early 20th century where they decided to get rid of all the books in the library that weren't scientific or that were a bit old. Then, it was in the 1970s, I think, where they decided to start producing complete folios on every single fellow of the Royal Society that had ever existed, which is obviously a huge task. What you see in the minutes is discussions about what kind of material they want on each person. They agreed that anyone after 1830, they just wanted the scientific papers, anything that's loosely understood as being scientific, whereas before 1830, they decided they wanted everything, because there's an understanding that what it meant to be a professional scientist around the 1830s changed a lot. You have these layers of ideals and ideology around what it means to do good science coming into and informing their decisions about how their archives should develop. This seems to permeate everything.
Samara Greenwood: That's such a fascinating story. As you said, when making those decisions, for instance, of what books to get rid of, that can be quite a different decision if it's made in 1930 versus 1970 versus today. There are going to be different kinds of things that are deemed, ‘okay, we can get rid of that’.
I love those two cases because on one hand, you're talking about a specific individual and everything that could possibly be related to that person. In the other case, this massive beast of a thing that just keeps growing and continually being reinvented. Such a lovely contrast.
So, I wanted to know then, how do the practices that we use to study historical figures change the kinds of scholarship produced. For instance, if we're doing traditional archival work versus digital humanities or other kinds of practices, are there ways that changes what kind of scholarship we come up with?
Kirsten Walsh: The most obvious cases of this is having these digital archives through which we can learn about Newton because we're able to use digital tools to explore these manuscripts. It isn't just the case that we suddenly have them all available in the one location, that's a huge development in and of itself, but we can search phrases and terms across all the documents at the same time. You can count the usage of terms. You can notice how many times certain phrases come up. Being able to use these kinds of digital tools allows you to interrogate the text itself much more deeply.
Related to that, one of the things that the Newton project has managed to do is that Cambridge University Library has digitised all of their Newton papers. They've produced images of all of them, so you can blow them up to any size you want. You can look at things on these documents that you couldn't see if you were just sitting in the reading room, and you can often get a clearer view of what a word that's been crossed out is because you can blow it up. That is very nicely connected with the transcriptions at the Royal Society. You can click through and hold these different documents on your screen at the same time. You can look at the transcribed version as well as the digital version and get a much clearer understanding of what's going on in these documents. That's really changed the way that we interact with Newton's documents.
The upshot of this is that Newton's work is much less compartmentalised than people have assumed it was in the past. People treated him as though some days he's doing his scientific work. He puts on his, mathematics hat. Then at other times he's doing his theology work. But what we find is that there's so much overlap in the way that his work is unfolding. Often, we find the same kinds of ideas are being written about in different places, and because he'd written about something in a way that looked more theological it got sent off with the theological manuscripts, but actually the ideas and the phrasing is very similar to say what he was writing about in the queries at the end of his Optics. Often Newton would be doing a whole bunch of mathematics on the page, and then he would pick up that paper later, maybe the same day, maybe a decade later, who knows, he tended to reuse his paper a lot, and he'd just flip it upside down. Then he would do a whole bunch of alchemy on the other side of the page. So, it's all mixed in together in a way that's really interesting and gives you a sense of how it is that he worked and how he approached this stuff.
Another thing that you get from seeing all this material together is the sheer volume of draft material that Newton wrote. Editing things over and over again. He was constantly reworking and rethinking even the various aspects of his published works, like the Principia. He was constantly rethinking how the rules in Book Three should be articulated and going over proofs in other parts of the book. You see the same thing with his Optics, where what you find in his manuscript material is new versions of the queries and things that often were just abandoned. Some of it went into later editions, but some didn't. You get this sense that, even with his published work, he never really considered these to be finished, completed.
It helps you to recognize that in Newton's mind, there was no definitive version of the Principia, or the Optics. He saw changes that he could keep making. You also find in his work other abandoned draft manuscripts and abandoned plans for books that he could write. This gives you a sense of what it took to produce the work that he did. Newton was a really smart guy. You do get the sense that often when he was doing an experiment or doing a mathematical proof, it would happen very quickly for him. He would just arrive at the conclusion and have to work his way backwards and figure out how to explain that to somebody else.
We often talk about scientific work as though the discovery or the drawing of the conclusion, making the inference, is the real part of the work, and that everything else is just tidying up after yourself. But that's clearly not what it was like for Newton. He makes these inferences, he makes these discoveries, carries out these successful experiments, but then there's so much work involved in developing the position, explaining it, writing it out, figuring out all of the implications of that position. And this work was never finished for him. You do get a very different sense of what it takes to be someone like Newton. It gives you a sense of what genius really looks like on paper.
Samara Greenwood: I think that leads well on to the next question, which is what do you think practicing scientists might find interesting about contemporary Newton scholarship?
Kirsten Walsh: Good question. There are a lot of things that I think scientists take for granted about their field. I think they take for granted the idea that what scientists are really aiming for is objectivity. They take for granted the institutional structures within which they work, the setting of a lab and the idea that what you need is to be able to build consensus within a community. The understanding of what the role of expertise is in their scientific work. What we see with Newton and his interactions with the early Royal Society, and with the early Royal Society's work more generally, is that these are all standards that are being negotiated. These are all things that they are deciding to prioritise for various reasons. So, we see challenges to expertise coming up all over the place.
One notable case of this is when Newton, early in his career, when he first sent his new theory of light and colours to the Royal Society, it got challenged by the Jesuits of Liège, as they couldn't replicate some of his experiments. That led them to dispute the veracity of the experimental results. Newton ends up having to try to defend and justify and explain how to do these experiments. He runs into this difficulty where he just can't get them to replicate the experiment correctly. He's sure that if they just did it right, they would understand and they would see where he was coming from, and they would recognise that he was right about this. But they just can't do it. He ends up trying to get the Royal Society to replicate the experiment in front of as large a crowd as they can so that at least there are eyewitnesses to the fact that his experimental results are in fact, correct.
So, you see this negotiation happening here. How important it is to build consensus about certain kinds of issues and how important that is to his reputation. I think present day scientists take it for granted that's just how science is, but it wasn't always that way.
Samara Greenwood: Lastly, I wanted to ask where you would like to see Newton studies heading in the future?
Kirsten Walsh: That's a good question. In my heart of hearts, I believe in an ecumenical pluralism [unity in diversity]. I think people approach Newton in a lot of different ways from a lot of different directions and I think that's a good thing. I think it's good that people interrogate his work with very different kinds of questions, very different frameworks in mind. But I also believe in the value of doing proper integrated HPS, and I think that interrogating the texts themselves really matters to this. I think that's important that we at least get the history right.
Often philosophers of science tend to look at Newton's work, focusing on the successful parts, of the places where he got it right. Those are really interesting and important. Everybody loves the moon test, right? Or everybody loves the reasoning via which Newton justified universal gravitation and it's worth understanding that inference. But I think that we could stand to spend more time looking at the messy cases and the cases where things didn't work as expected. George Smith has done a lot of important work on Book Two of Newton's Principia, for example. This is a case where Newton starts exploring fluid dynamics. But it tends to have been ignored by philosophers of science as a case where it didn't really work. It's not correct. But Smith has rehabilitated the second book, or at least made us realise that we should be focusing more on this as a really important case where we see Newton's reasoning.
I think that in general this is something worth doing with Newton's work, looking at the cases where things don't quite work the way he was expecting them to, where he hasn't managed to arrive at a perfectly mathematical account of his Optics or something like that. Because I think these are the cases where we get better insight into what his practices, in fact, were or how he thought we should be approaching study of the natural world. One of the things we see when we look at his methodology not working is how the natural world matters to the kind of methodology that he's applying. Sometimes the world just doesn't do what you want it to do, so the nature of your target system seems to really matter to the kind of method you're going to use.
So, I'd like to see Newton scholarship continuing to be messy in a good way, and I think it could be messier by focusing a lot more on the things that we might think of as failures or the places where it doesn't work, or it doesn't conform to our expectations of what modern science should look like. I think we could also stand to recognize Newton's interactions with other people a lot more and think about him, not just as this kind of isolated genius, because I think all the evidence suggests that he was never as isolated as everybody has said, but recognising him as somebody who was interacting with other people and that he was learning from other people and drawing on ideas from other people and also influencing other people.
Samara Greenwood: That's fantastic and a great place to finish the episode. I wanted to thank you so much, Kirsten, for being on the podcast. I thoroughly enjoyed our conversation today.
Kirsten Walsh: Thank you for inviting me. It's always fun to talk about Newton and about my research.