Experimental Cartesianism and the problem of space

Mihnea Dobre

University of Bucharest

Notoriously, Descartes does not have a concept of space. Or better said, he uses space as indistinguishable from matter or extension. Yet, to some of his contemporaries, his physics was successful at providing mechanical descriptions of the natural world. In this paper, I shall discuss the problem of “space” within a larger Cartesian framework, focusing on how experimentally-minded Cartesians took the challenge provided by Descartes’s restrictive ontology and tried to accommodate it with experimental results. One of the most famous debates in the seventeenth-century natural philosophy was about the existence of void space. New instruments were built with the particular purpose of providing clear evidence to support this claim. A large secondary literature was devoted to this problem, however, a study of the Cartesians involved into such discussions is still lacking. Most of the time, Descartes’s followers are taken to merely repeat his words about the contradictory nature of vacuum, hence, their experiments are portrayed as rather misplaced practices. At most, one would find in the literature a discussion about the pedagogical value of these experiments. The consequence is that new experimental approaches provided by Cartesians after Descartes’s death in 1650 are unfortunately neglected. By building upon a recent work on Cartesian Empiricisms, my aim in this paper is to explore the notion of space within Cartesian experimentalism. In doing so, I shall refer to the works of Burchard de Volder, Jacques Rohault, and Samuel Clarke’s annotations to Rohault’s text. Some of the questions I would like to address are as follows: why would a Cartesian natural philosopher perform experiments that are clearly connected to a concept of independent space? What would be the expected outcome? How does the theory (in this case, the Cartesian matter theory) relate with the empirical evidence? And how would the later influence the former? Such questions are relevant for the history of experiment in the early modern period. At the same time, they offer more insights into one of the most intricate problems of Cartesian philosophy, the relation between metaphysics and physics. Moreover, this problem can further illuminate our understanding of the transformations that lead eventually to the formation of modern science.