George Sarton is known as the "father of the modern history of science". He wrote many works on medieval history and was the first editor of Isis, an important journal of the history of science. George Sarton has been accused of a personal bias against Christianity and religion. If this is true, it is very important. Many of the myths about church and science have survived decades or even centuries longer than they should have (see The Galileo Myths). Since George Sarton was editor of Isis from 1913 to 1952, the answer might be in these volumes.
The seventeenth century saw many advances in many areas of modern science (see Galileo Contemporaries Timeline). One area was the study of motion (kinematics and dynamics). Galileo developed his Law of Free Fall and Galileo and Newton both contributed to an understanding of momentum and inertia. Their advances were considered important in the early volumes of Isis and were covered well. The advances of their predecessors in Medieval Europe were not. The takeaway was that there was nothing from these predecessors of value. That takeaway was wrong. And all the pieces were already there to tell George Sarton and other early historians of science that it was wrong.
Galileo and Newton didn't start from scratch in their study of motion. When Galileo's Law of Free Fall was first published around 1560, it was derived using theories and proofs proposed by the Oxford Calculators and Parisian Doctors three centuries earlier. When Galileo presented his concept of impetus, he was improving on the work of Jean Buridan, a Parisian doctor. When the scientists of the seventeenth century used mathematics to represent physical concepts, they were continuing a calculatory tradition begun by the Calculators and Parisian doctors (henceforth Calculatores will be used to refer to both Calculators and the Doctors).
So what's the problem with Isis overlooking a few obscure medieval academics from Oxford and Paris. The problem is that they weren't obscure! By the time Galileo was born, the work of the Calculatores was widely published and widely taught. You can find references to the Parisian Doctors in Galileo's school notes. They were important to the discussion of the church and science since they were all Roman Catholic clergy. The image below is derived from a book by Walther Hermann Ryff (see W. H. Ryff) published in Galileo's teenage years. It illustrates a projectile trajectory based on Buridan's impetus theory.
The Calculatores were very well known. One Calculator, Archbishop Thomas Bradwardine, had even been mentioned in one of the classics of English Literature, Geoffrey Chaucer's The Canterbury Tales. In a sign of special respect from the church, Bradwardine had been bestowed the honorary title of doctor profundus. The calculatory tradition of Oxford and Paris had spread to what is modern day Portugal, Spain, Italy, Germany, France, and Poland. The map below shows some of the universities associated with the Calculatores. Notice that these include Pisa, where Galileo studied, and Padua, where Galileo taught.
The Calculatores derived the Mean Speed Theorem, proved it geometrically, recognized that kinematics and dynamics should be studied separately, developed graphs to represent motion and proposed the equivalent of the odd number rule for uniformly accelerated motion. With this groundwork, it should surprise no-one that the first publication of Galileo's Law of Free Fall happened four years before Galileo was born. In 1560, Domingo de Soto, a Spanish calculator and priest, published a commentary on Aristotle's Physics, which outlines the correct law of free fall. It was already in its eight edition during Galileo's university days at Pisa [_1_] .
There was little mention of the Calculatores during Sarton's time as editor. There was one article (written in German) in Isis devoted to Thomas Bradwardine and none to Jean Buridan. Buridan was mentioned in a 16-page survey of physics that covered all physics over the entire middle ages [_2_] . The sparse mention the Calculatores and Parisian Doctors might be due to George Sarton's poor opinion of them. This was voiced in his own writings on the history of Medieval Science.
The pieces were there to tell Sarton that ignoring the Calculatores was a mistake. They were laid out in detail by an early historian of science, Pierre Duhem. Pierre Duhem's reward was to be made a persona non grata.
If George Sarton had a bias against the church or Christianity it would not have been unusual. It was common amongst the English-speaking historians of Science in the nineteenth and early twentieth century. As an editor, he would be expected to keep his biases in check. One test of his bias was the treatment of Pierre Duhem. Duhem was a world-renowned Thermodynamicist and Philosopher of Science who decided to investigate the history of science in later life. Duhem had discovered that Roman Catholic clergy (Calculatores) from the Middle Ages had made important advances in physics. These advances had been attributed to later scientists.
Duhem's discoveries must have been hiding in plain sight. He made them soon after starting his studies. Are we to believe they eluded other historians for another four decades? Or was it a question of editors not historians. In Sarton's own works on Medieval Science he had dismissed the importance of the Calculatores.
Duhem started with the same "dark age" bias as his colleagues. He expected to find nothing of importance from the middle ages. In studying the work of Leonardo da Vinci, he quickly stumbled upon the work of the Parisian doctors and realized that they had made some very important discoveries in physics. Showing that there was light in the 'dark ages' would prove disastrous.
Duhem's considerable body of work was referenced in barely one article per year while Sarton was editor. Shortly after Sarton founded Isis, Duhem submitted volume 1 of the Systeme du Monde, a 10-volume set on the history of cosmology from the Greeks to Copernicus. It received a positive review in Isis and Sarton let Duhem know he was looking forward to his other volumes. The first volume was the last one that would be reviewed. The first volume was focused on the Greek contributions to cosmology. Duhem's treatment of Medieval scholars in the succeeding volumes was a direct challenge to the conventional view of the history of science and the current view of church's relationship with science. Duhem died in 1916. A proper appreciation of his work in Isis would have to wait until after Sarton stepped down as editor in 1952.
Sarton authored several large volumes of work on medieval science. In some of Sarton's works on science in the middle ages, Duhem and his work aren't mentioned at all and in others he is only very rarely referenced. This for a man who is now considered the premiere student of European medieval science in the early twentieth century.
One article that George Sarton approved for publication deserves special mention; a 1936 article by a graduate student on Pierre Duhem's work on a medieval scientist, Jordanus Nemorarius. It was a combination of hit piece on Duhem the man, and a criticism of one of his works. It was tremendously condescending of Duhem, even questioning his scientific acumen [_3_] . A modern academic would be surprised that any editor would allow the publication of such an article, especially since the author was still a graduate student and Duhem was world renowned in thermodynamics and philosophy of science.
The important contributions of the Parisian Doctors and Calculators are now widely accepted. In fact, Duhem's work is of more interest to modern historians than that of his contemporaries; including George Sarton [_4_] . Duhem's discoveries happened shortly after he started his investigations. They must have been hiding in plain sight. It is difficult to believe that they would elude other investigators for four more decades.