Theme
RK: Please join us this month for an extended riff on our favorite early modern astronomer (and Platonist, sci-fi writer, and mom-defender, among other things): Johannes Kepler. He was a great scientist, but also so much more—and his intersection with the world of rare books is so much more than just as a writer of astronomical discoveries. Despite these facts, he often gets unfairly overshadowed by his less complex contemporaries, so we are here to bring a little bit of Keplerian evangelical fervor to your day. Jason, what is your Kepler origin story? How did you get Kepler-pilled?
JWD: CUE THE RACKETT PROCESSIONAL MUSIC! KEPLER IS HERE! I know we’ve hinted at our abiding love for Kepler around here since we started (we even snuck a Kepler reference in Paul’s interview), and it’s fun to finally come to the heart of the matter.
I think my love of Kepler is really in two phases (pun not intended). I have a very vague memory as a child of watching Carl Sagan’s Cosmos in reruns, because when I watched this clip about Kepler it was surprisingly familiar to me:
Watching the show as a child would have been on-brand for small Jason, who also enjoyed James Burke’s Connections. So, that was dose one for me - Cosmos.
The second dose (and when it became infectious) was when five years ago or so I read Arthur Koestler’s The Sleepwalkers: A History of Man’s Changing Vision of the Universe, which seems to be a big touchpoint for a lot of folks I know in the field.1 Koestler really sets the reader up to be keen on Kepler (is that the bumper sticker, RK?), contrasting him nicely with Brahe.
It’s that contrast that was at the core of my initial interest in Kepler - Brahe is undoubtedly important, and much of early modern astronomy would not have been possible without his observational data, and his work refining naked-eye observations. But Tycho, well, he loved shenanigans and goings on. Fake nose? Check. Getting a moose super drunk? Check. An island castle, complete with dungeon, fit for the man who seems low key to be the early modern evil genius of astronomy? Check! (although he lost Uraniborg). After all that noise and Brahe’s failure to publish his life’s work in his lifetime (which was only finished by Kepler at great effort and expense in the Rudolphine Tables), Johannes Kepler is really refreshing. (RK: as an aside, I have recently undergone a swell of newfound appreciation for Tycho—which got me slightly chastised by a consignor last season!! I recommend the In Our Time episode2 about him).
I think the other thing that really commends Kepler to me is that he, as Sagan talks about in the show, sought to find the harmonies of the universe he desperately wanted to find, but was willing to set those to the side when he was able to describe, conclusively, what he observed in the motions of the planets. An added bonus is that while he is bookended by more famous astronomers - Tycho Brahe and Galileo Galilei come to mind - he is less well known to the broader public, and I suppose that’s not surprising. Brahe had such a wild story and Galileo, is, well, Galileo. But Kepler and his work was so wide ranging: what we would today describe as one of the earliest works of science fiction - the Somnium, the three laws of planetary motion which finally described the motions of orbits correctly rather than epicycles, he brought Tycho’s work to fruition in the Rudolphine Tables, he improved the refracting telescope and laid the foundations of the reflecting telescope, and gave us some of the most charming and compelling early modern astronomical works.
What about you, Rhiannon? What was your road to Emmaus Prague moment with our boy?
RK: I had a vague awareness of Kepler during my classicist student days because of his Somnium—which has a few things in common with a work by one of my favorite ancient authors, Lucian of Samosata’s True Story. So there was already a cool factor. But the person who really inducted me into Kepler-world was James Voelkel, the curator of rare books at the Science History Foundation. He came to visit the Getty back when I was a wee assistant there and during lunch he explained the wonders of Kepler’s Astronomia nova to me.
James’s great monograph on the Astronomia nova goes into detail not only about the importance of Kepler’s discoveries, but his care in expressing them through not just language but in the structure of the book itself. Certain types of information are set in italic and others in roman, giving readers with different backgrounds a visual guide to the passages which are most of interest to them. I think this just really clued me in to the fact that Kepler had a lot going on intellectually which isn’t appreciated when he is viewed in a sort of “great men of astronomy” context. He was a Renaissance thinker deeply engaged with a wide range of ideas and technologies, both ancient and on the cutting edge.
The more one learns about his life, the more interesting he becomes—but he doesn’t fit into easy boxes. He was inspired to become an astronomer after his mother took him to see the Great Comet of 1577 at age 6. As a student of Michael Maestlin, he became an avowed Copernican and spent much of his career working to “solve” the mathematics of the Copernican system. While Galileo is famous for his (arguably somewhat self-inflicted) conflict with the Catholic church, Kepler’s career and life trajectory was certainly also affected by religious persecution—by both Catholic authorities and his fellow Lutherans, sadly for him. I have seen copies of his books expurgated by the censor. The intense religiosity and even mysticism of his work is inconvenient to those who love a narrative of science vs religion.
Kepler was incredibly prolific, both as a correspondent and an author. His books cover not just the astronomical discoveries he is most famous for now, but as we mentioned, a science-fiction fable about going to the moon, a guide to measuring the volume of wine barrels that prefigured the discovery of integral calculus, and a book on optics (after all, how can you write about anything if you don’t first know, literally, what you’re looking at?). His mother was accused of witchcraft and he defended her in court. We have barely even touched on the HBO-worthy drama of his relationship with Tycho and the struggle with his heirs. All this while transforming the science of astronomy!! Sweet saint Kepler (did you know, also, that Kepler and Copernicus are celebrated by a feast day in the Episcopal Church?). The frontispiece of the Rudolphine Tables kind of says it all: Tycho up front with all the biggies, and himself in the basement writing away.
His work has a such a clear vision of the unity of physical science and the abstraction of mathematics and harmonics, and a balance of theories as big as the universe with the sweetness of the little details of the world—like the physics of a snowflake. How can you resist?
Two Four Cool Things
While we normally talk about two cool books here, I mean, our prince Kepler deserves four!
RK: For the last decade, I’ve spent a lot of time thinking about the work of Plato and the reception of his philosophical legacy in the Renaissance (which I feel is badly misunderstood by many, but that’s for another time… maybe we’ll do an issue On Materialism someday!). How could I not be swept away by Kepler’s awesome Platonic vision of the universe in the Mysterium cosmographicum?
Published in 1596, his first serious work, the Mysterium explores ideas Kepler had begun to develop while teaching mathematics in Graz. According to Aviva Rothman,
"Kepler demonstrated that by nesting the Platonic solids one inside the other and then circumscribing circles around each one to represent the planetary orbits, one could arrive at the distances between the planets, ordered according to Copernican theory. Because there were only five Platonic solids, it was clear that there would be precisely six planets. Kepler further argued that the structuring of the cosmos according to the Platonic solids made perfect sense, for geometry was the tool with which God had created the universe and all things in it. To be intelligible was to be geometrical, Kepler contended, because the human mind was imprinted with the very geometrical archetypes that also structured the cosmos and was therefore uniquely suited to understand God's creations.”3
Obviously, this is a bit crazy—and also ultimately incorrect, as he acknowleged himself. The math didn’t quite work, although it was very suggestive (also, as we know now, there are more than six planets…). But it did catch the attention of powerful patrons on the world of astronomy, and present Kepler to the world as a man of unusual skill and genius. The basic underlying idea that the abstract world of mathematics should also reveal the physical truth of the universe was the seed of what is really Kepler’s legacy to the history of astronomy.
The questions Kepler was asking in this book: why are there six planets, and why they have the relationships to each other that they do, were questions he kept asking throughout his life. Although based on a partially flawed premise, they brought him to Tycho Brahe in search of new and better data—and ultimately to the discovery of the orbit of Mars, the laws of planetary motion, and a firm confirmation of the Copernican system. (And having just cataloged the Pasachoff copy of this book, although I don’t know how much control he had over the printing, I can’t help but think there is something relevant about the fact that it is perfectly imposed in 4s in gatherings signed A-Z—no funny business! That’s divine geometry for a bibliographer).
For my second Cool Thing, we’re moving from the big questions to the little ones, and one of Kepler’s very sweetest little books: Strena, seu, De niue sexangula, printed in 1611. The title translates as “The New Year’s Gift, or, On the Six-pointed Snowflake.” Written in the form of a letter to his patron, Wacker von Wackfels (recipient of said “gift”), it asks the question: why do all snowflakes have sixfold symmetry? And although he doesn’t actually answer that question, he uses it as a pretext to explore ideas about mathematics and pattern in nature.
I’m sorry, can we just contemplate this man as a math teacher for a moment? I’m sure if he had taught me, I would have made it to calculus (you know, if calculus had been invented yet). Now very rare, it would make a very good present indeed—I’ve only ever seen one copy in person; the one illustrated here is from Linda Hall.
JWD: I’m going to go a little outside the really well known Kepler works, I think, but remain on brand with two very small publications by Kepler, one in 1610, and one in 1612: the Dissertatio cum Nuncio Sidereo and the Narratio de observatis, respectively. Surprising no one, they are both related to Galileo’s Sidereus nuncius, and one of them is the direct result of one of two epistolary exchanges we have between titans of early modern astronomy. In 1597, our man Kepler sent Galileo a copy of Kepler’s semi-recently printed Mysterium cosmographicum, which GG acknowledged in a letter that same year.4 It’s not a long letter, really, and neither correspondent had yet reached the height of their fame and renown. Kepler sent an enthusiastic reply to GG’s acknowledgement and got… no response. I can only imagine how disappointing that might have been for Kepler, but given the pace of Galileo’s correspondence and his little fits he threw, it’s not too much of a surprise in hindsight. Kepler didn't give up and sent word a few times through colleagues he was keen to hear more from Galileo and that he held the Tuscan (he’s in Pisa at this point) mathematician and natural philosopher in high esteem. After a while, Kepler gets the hint that GG ghosted him and gives up.
Thirteen years later, things are much different for our golden boy (yes, Kepler) - he’s now in Prague, and has succeeded Tycho as the Imperial Mathematician to Emperor Rudolf II. Kepler held one of the most important and prominent “scientific” posts in early modern Europe. His immediate predecessor was the half-nosed villain, but Kepler’s work also landed him the post. He’d published some important work - De stella nova, Astronomia nova, and the now-famous Somnium. Galileo moved from Pisa to Padua, but now his star was dimmer than Kepler’s (yes I intended that joke).
When Galileo’s Sidereus appeared in March, 1610, Galileo sent a copy to Rudolf II, and Kepler was keen to read the book that was very much the talk of scholars at the time. Though the book was quickly unavailable due to intense interest, the learned community was initially very critical of the little book, and of the existence of the moons of Jupiter. Galileo was an astute political operator, and sought to appeal to - you guessed it - Kepler, the man he ghosted 13 years earlier!
On April 8th, Giuliani de Medici hand-delivered a copy of Sidereus for Kepler to read, with a covering letter from Galileo, requesting Kepler’s opinion of the work. GdM was to leave Prague for Florence on April 19 - in those 11 days in 1610, Kepler swallowed the epistolary slight and wrote the Dissertatio cum nuncio sidereo, which he both had printed and sent with GdM under a covering letter. Kepler really (pun not intended) did a SOLID for Galileo here (Platonic solid? RK?) and wrote what was a laudatory book review. Kepler did not have a telescope of sufficient quality and power to confirm Galileo’s observations, and so the Dissertatio was more of a “nice work, Galileo, you’re probably not wrong” situation. Kepler did as Galileo in the open letter for a review of his Astronomia nova, but well, Galileo didn’t even deign to send that. Again.
Of course, reading Sidereus whetted Kepler’s appetite to see these new fantastic satellites, and to look at the moon, etc etc. But, like I said above, our man in Prague didn’t have a telescope of acceptable quality to reproduce these results. He managed to borrow a Galilean telescope from Ernest of Cologne, Duke of Bavaria, who was gifted one of GG’s snazzy telescopes. From August 3 to September 9, Kepler finally was able to see the satellites with his own eyes! Here’s how Max Caspar describes it:
Thus the latter [Kepler] was finally in a position to observe with his own eyes what he had so longed to see. In the presence of Benjamin Ursinus, the young mathematician, and several other guests, he observed Jupiter from August 30 to September 9. To preclude any error, each one individually, without the knowledge of the others, had to draw in chalk on a tablet what he had seen in the telescope; only afterwards were the observations from time to time compared with one another. Kepler published the results of these observations in a booklet entitled Narratio de Jovis satellitibus. This was reprinted in Florence in the very same year so that, in Galileo’s native land too, it served as a strong witness for the credibility of the new discoveries.
That’s my last cool thing for this issue - the Narratio, which is crazy rare in the first Prague edition. The Narratio was the first independent, directly observed, confirmation of Galileo’s observations.
The books are so small, so not illustrated, so rare, and so important. It belies this triumphalist narrative around Galileo and Sidereus, and I think shows a generous side of Kepler - he really did help Galileo out when he repeatedly had little reason to. THANKS KEPLER.
Current Events
JWD: So one of the great folks out at the Getty Museum (former RK stomping ground!) Larisa Grollemond, just had an exhibit they curated open out at the Getty - Blood: Medieval/Modern which I desperately hope to get to be able to see (it runs February 27–May 19). Rhiannon, since we’re both lapsed anglo catholics, I suspect this would appeal to both of us. When she posted the notice about it on her instagram, I sent Larisa a lightly jokey message about trans substantiation - and good news there’s some “mass of st Gregory action,”per Larisa. The labels are really great, and I hope there will be some interactive content too in case folks can’t make it out to the hill over the city of angels.
I’m also poking around the big NYC museums for exhibition intel, and though not bookish, I will absolutely be visiting the Met for this AMAZING Pueblo pottery show - Grounded in Clay, another thing I collect (collectors gonna collect, I suppose). It’s really nice to see a rich website for the show too, and if you like the pottery, it’s a nice education, too. Friends, if you know of interesting exhibitions happening during NYABF, give me a shout?
Finally, I’ve recently announced our two After Hours programs for the year at LHL - the first one is open - I’m damn excited to be joined by noted internet person, scholar, and medievalist Seb Falk as we talk about one of LHL’s Sphaera mundi by Sacro Bosco - you can register here, it’s free, virtual, and will be in June. The second After Hours will be Finch presenting with Anna-Marie Roos, on the Listers and what we’ve taken to calling That Damn Shell Book.
RK: I’ve mostly been cloistered at my desk, but on the first of March, I escaped down to Baltimore to visit the students at the Virginia Fox Stern Center for the History of the Book in the Renaissance at Johns Hopkins. I had a really enjoyable and thought-provoking afternoon talking about the history (and present) of private collectors and bookselling, the wider ecosystem of “rare book world,” and how these players all interact to put together collections both private and public.
While there, I was able to catch one of the final days of the Walters Museum exhibition Ethiopia at the Crossroads, the first major art exhibition in America devoted to Ethiopia. It was curated by a former colleague from my Getty days, Christina Sciacca, so I knew it would have good book content and it did not disappoint! Unfortunately it has just closed, but there is an already back-ordered catalogue which will hopefully be available again soon.
Let’s Get Personal
RK: Well. My big news is that this is my final month at Christie’s! After almost seven years, I decided that I like selling books so much, I might as well become a “real” bookseller. So, if you need anything from “Christie’s-Rhiannon”, you better ask soon. I’ll be taking April off to decompress and move my worldly belongings down to Philadelphia, where I’ll be joining the brilliant crew at Bruce McKittrick Rare Books. I have enjoyed many things about the auction world, but I am looking forward to devoting myself more fully to continental books and bookselling. If you want to know more details, you’ll have to buy me a drink! Speaking of…
JWD: I know we’re both getting locked in for the New York Antiquarian Book Fair next month. It’s my first time in the city post Hertzog talk at Grolier, and Rhiannon is going to be moonlighting at Nina Musinsky’s stand. Our dance cards are filling up already, but if you’re reading this, please say hello - we’d love to chat with our readers!
We should also say to our surprise and great joy - Half Sheets to the Wind has well over 100 subscribers, which is amazing, given we’re only (including this one) 3.5 issues in. We’re thrilled with this, and surprised so many of you are interested in our little monthly musings. If you see us in person and have feedback - let us know! I mean this is mostly a thing we do for fun, but we’re interested in some small course corrections, issue ideas, interview ideas, etc. Also, encourage your friends and colleagues to sign up to keep in on the fun. We have some really great things in the mix coming soon.
One more thing - we’re gratified you all enjoyed our interview with Paul so much, and we’ve been sending each other things related to his interview. This quote from the recent profile of G. Thomas Tanselle in the Times Literary Supplement struck home:
“Books are physical objects made by human beings.” G. Thomas Tanselle’s words (in A Bibliographer’s Creed, 2014) are a reminder that bibliography involves not just he study of “physical objects,” but also of the motives of the “human beings” who shape the ways in which books are created. The challenges of such study are considerable at a technical level: they can involve the study of type, paper, typesetting, illustration and binding (and much else). They also require the bibliographer to have the instinct of a psychologist and to probe the human capacity for messiness, muddle and irrationality that can affect the book at every stage in its creation.
Conclusion
Speaking of NYABF, we’ve got a special surprise for the next issue - Lord willing (and the creek don’t rise), we’ll be doing our next issue live from NYABF! We’re already scheming about how that might work. Also, the Major New Acquisition Jason has been teasing will be shared in the next issue, since it will be announced generally in late March.
Rhiannon, I think you love that book, as do my colleagues Bill Ashworth and Ben Gross. Even noted Internet Hulk, Thony Christie likes it.
https://www.bbc.co.uk/programmes/m001hnlf online here (and the Kepler ep is great too of course
Aviva Rothman, The Pursuit of Harmony: Kepler on Cosmos, Confession, and Community—a really wonderful book on the philosophy underlying a lot of Kepler’s work.
Find this in Favaro’s Opere, vol. X, pp. 67-68.
Thanks for this piece. Kepler was only a name to me before I read it.