John Lynch has been posting the slides from his lectures for his course History of Science II (since 1700) at Whewell’s Ghost and very good they are too even without the lecture text. In the third lecture, The Scientific Revolution, he has a slide (#8) showing Copernicus’ De revolutionibus and he has written, “ Owen Gingerich has called it “the book nobody read””. Unfortunately he is here suffering from a misconception. It was actually Arthur Koestler in part three, The Timid Canon, of his book on the history of astronomy, The Sleepwalkers, who titled the first section of the second chapter (The System of Copernicus) The Book That Nobody Read. Gingerich used the title sarcastically for one of his own books because he believed that his researches had proved Koestler wrong. I’m going to go into more detail here not because I wish to correct the excellent Mr Lynch but because I think that Gingerich does Koestler a disservice.
Gingerich spent thirty years or more cataloguing all of the still existing copies of the first and second editions of De revolutionibus detailing all of the marginalia that they contain and publishing the results in his unbelievable An Annotated Census of Copernicus’ De Revolutionibus (Nuremberg, 1543 en Basel, 1566), Brill, Leiden/Bosten/Köln, 2002, an invaluable documentation for all historians of astronomy. In 2004 Gingerich published a popular book, The Book Nobody Read: Chasing the Revolutions of Nicolaus Copernicus, Walker & Company, New York, which details many of the adventures he had tracking down the copies of De revolutionibus in order to compile his census. In the preface to this book Gingerich writes,
De revolutionibus was branded “the book nobody read” by Arthur Koestler in his best-selling history of early astronomy, The Sleepwalkers. Koestler’s highly controversial account, published in 1959, greatly stimulated my interest in the history of science. [mine too] At the time, none of us could prove or disprove his claim about Copernicus’ text.
Koestler was, I am happy to report, quite wrong in declaring that De revolutionibus was the book that nobody read, though it took the better part of a decade to be sure and thirty years to carefully document the book’s impact.
In his census Gingerich does in fact show that nearly all the known astronomers and mathematicians in the second half of the 16th century and the early part of the 17th owned, read and annotated copies of De revolutionibus. Interestingly his census also shows that the vast majority of the readers only read the technical mathematical part of the book and completely ignored the cosmological heliocentrical first chapter. This shows that they were basically only interested in whether Copernicus’ models produced better astronomical predictions than those of Ptolemaeus. His heliocentrism found very little interest among the experts.
So why do I claim that Gingerich does Koestler a disservice? After all Gingerich’s researches clearly demonstrate that Copernicus’ contemporaries did ‘read the book’. Gingerich does Koestler a disservice because this is not what Koestler was claiming when he coined the disputed dictum. Koestler is concerned with ‘modern’ historians who claimed that Copernicus had substantially simplified Ptolemaeus’ model of the universe in De revolutionibus. In fact as Koestler shows Copernicus needs a total of 48 circles for his deferents and epicycles whereas the actual geocentric model in use in the middle of the 16th century only needed 34 circles. The people who did not read De revolutionibus were not Copernicus’ contemporaries but the modern historians writing about the book.