ABSTRACT
Sir Kenelm Digby’s posthumous reputation as a natural philosopher ought to be much greater than it is. He was the fi rst English natural philosopher to publish a fully worked-out system of mechanical philosophy. His Treatise on Body appeared in 1644, the same year as Descartes’ Principia philosophiae, and had something like the same range, if not the same intellectual power.1 It also had the advantage, at least for its prospects in anglophone historiography, that it was written in English. Although his system was clearly inspired by the philosophy of Descartes, which Digby knew about thanks to his association with Mersenne and his circle in Paris (Digby read the Discours de la méthode when it fi rst appeared in 1637, corresponded with Descartes the following year and in 1640 he visited Descartes in Amsterdam),2 and so ultimately derivative, there is a sense, nonetheless, in which Digby’s system of natural philosophy was genuinely original. At the detailed level its differences from all the other versions of the mechanical philosophy mark it out as particularly interesting. He should be given credit, therefore, for developing, and making public, a comprehensive and cogent natural philosophy before those who are more frequently mentioned as philosophical rivals to Descartes, such as Thomas Hobbes, Pierre Gassendi or Robert Boyle. Comparisons, as they say, are odious, and certainly arguable, but it could be argued that Digby’s mechanical philosophy is less derivative from that of Descartes than the systems of either Hobbes or Gassendi and compares favourably with theirs even though none of them achieve the internal consistency and power of the Cartesian system.
