I first stumbled across Isaac Beeckman when I was learning about the early history of the telescope. In his Journal, about which more later, he wrote how Johannes Zachariassen, who was teaching him lens grinding, explained how he and his father Zacharias Janssen invented the Dutch or Galilean telescope, the microscope and the long or astronomical telescope. Despite various dubious aspects to this claim this was one of the sources that Cornelis de Waard used at the beginning of the twentieth century in the first modern history of the telescope in naming Zacharias Janssen as one of the three inventors of the telescope. Modern research has shown that Janssen could not have been one of the inventors of the telescope.
The second time I came across Beeckman is when I discovered, I can’t remember where, that Newton’s first law of motion, the law of inertia, was not, as often claimed, taken from Galileo or from Galileo via Descartes but from Beeckman via Descartes. This is something that I have over the years pointed out also pointing out that Galileo’s law of inertia was false because he believed that natural motion was always circular whereas Beeckman hypothesised, correctly, that it is linear. I have also been systematically criticised over the years by people saying, also correctly, that Beeckman believed that linear and circular motion are both natural motion, of which also more later.
For a long time this was almost the sum total of my knowledge of Isaac Beeckman but it was enough to place him on the very long list of people I would like to know much more about. Recently Linda Hall Library had Beeckman as their scientist of the day and I discovered that Klaas van Berkel had written a biography of Beeckman, which appeared in English in 2013. Now I know Klaas van Berkel and know that he is an excellent historian of science, so I acquired his book and having now read it I know a lot about Isaac Beeckman, a truly fascinating seventeenth century scholar.
Isaac Beeckman was born, the son of Abraham Beeckman a candle maker, in Middelburg in Zeeland in 1588. His father was Counter-Remonstrant the strict orthodox wing of the Calvinist Church in the Dutch Republic and Isaac adhered to this theological stand point all of his life. Isaac went to the University of Leiden in 1607 but before he went he spent three months studying mathematics with Jan van den Broecke a distant relative. His course of studies in Leiden was the liberal arts and theology but he went to Rudolph Snel van Royan (Rudolph Snellius), the father of Willebrord Snel and an important figure in the early history of science in the Dutch Republic, and asked him to recommend books for a course of self-study in mathematics. He pursued this course of study so intensely that he suffered a minor breakdown. However, he recommenced his studies and left the university in 1610.
Back in Middelburg he went to work for his father and within a year he qualified as a master candle maker and set up his own company. Leaving the candle making to his foreman he devoted his energies to working as a hydro-engineer. In those years he travelled much and also studied much. In 1618 after two years of self-instruction he took his master’s degree in medicine at the University of Caen. In 1619 he became vice rector of a school run by one of his brothers. Later he would go on to become rector of his own school and schoolmaster remained his profession until his relatively early death in 1637, only 49 years old.
From his early days as a student Beeckman was a passionate natural philosopher and he wrote down his thoughts, speculations, theories, experiments and deductions in what he called his ideas book and which is now known as his Journal. Very early he rejected the dominant Aristotelian world-view and developed his own version of an atomist philosophy including the acceptance of a vacuum surrounding his atoms. He also developed a mechanistic philosophy of motion. This requires physical contact between objects for changes in motion. However Beeckman also took the step of rejecting rest as the natural state and developed a theory of inertia. In opposition to Galileo, whose theory he didn’t know at the time, Beeckman’s theory of inertia sees natural motion as linear and not circular. He also so accepted circular inertial motion but aware that objects on a rotating disc shoot off at a tangent thought that circular inertial motion would almost never be observed in normal circumstances.
In 1618 Beeckman met and got to know the young René Descartes in Breda in Holland. Descartes was much impressed with the Dutch amateur natural philosopher and eagerly read and absorbed the idea book. During their time together Beeckman explained to Descartes his physical theory of fall and Descartes correctly derived the mathematical laws of fall from it; he was a much better mathematician than Beeckman. This was of course well before Galileo published his own derivation. Curiously Descartes would later reject his own derivation because it was dependent on the acceptance of a vacuum, which he rejected.
Later Beeckman came into contact with Pierre Gassendi and Marin Mersenne who both visited the philosophical schoolmaster and read with interest the idea book. Both of them kept in touch by letter on their return to Paris.
Beeckman’s influence on Descartes and his later philosophy was substantial, although Descartes later denied it when he became famous and over the years Descartes scholars have tried to sweep it under the carpet. Beeckman, who produced the first mathematical law of music, corresponded fairly extensively with Mersenne on the subject, an area of interest that both men shared and he certainly influenced Mersenne’s work on the subject. Gassendi is credited with having made atomism acceptable to the Church, the Greek theory being tainted with its association with atheism. He did so after first becoming aware of Beeckman’s atomism a theory developed by a deeply religious Calvinist.
Beeckman’s Journal was never published in the seventeenth century and was for a long time thought lost until it turned up at the end of the nineteenth century. As a result and because of Descartes very nasty dismissal of his work he became a forgotten figure until Cornelis de Waard published the Journal in the twentieth century. Research, since that publication, has shown that Beeckman was an important and influential figure in the evolution of modern science in the seventeenth century.
An important aspect of the Beeckman story for the history of science lies in the fact that he published nothing during his own lifetime. Historians have a strong tendency to orientate themselves on published books and develop a cannon of the important books that delineate the evolution of science. Beeckman’s life story, however, shows that personal contact, private conversations and correspondence can play just as big a role if not an even bigger one in that evolution.
Klaas van Berkel’s book on Beeckman’s life and work is excellent and goes into much more detail than I can in a brief blog post. As well as the main text it has very extensive endnotes with many recommendations for further literature on every single topic dealt with in the main text. I would recommend it to anybody who is really interested in the history of the evolution of modern science in the seventeenth century.
 Klaas van Berkel, Isaac Beeckman on Mater and Motion: Mechanical Philosophy in the Making, The Johns Hopkins University Press, Philadelphia, 2013.