 More followed this up with what he called an essay, but which was still written in sub-Spenserian stanzas, on “the Infinity of Worlds out of Platonick Principles”. Democritus Platonissans (1646), accordingly, is the part of More’s philosophical poem cycle which deals with the material side of the dualist dichotomy. He may have been inspired here by the Two Treatises of Sir Kenelm Digby (1603–1665) which had just appeared (1644), and which he mentions in the notes to his poem. Digby developed a version of atomistic natural philosophy and argued that all change is nothing more or less than a re-arrangement of the material atoms comprising all bodies. Consequently, Digby went on to argue, immaterial souls cannot change, and must therefore be immutable and immortal (Digby 1644, 350). More used the same general stratagem with regard to the relationship between body and soul in his poem, and it was presumably during the writing of Democritus Platonissans that More first became interested in the latest developments in natural philosophy (Thomson 2008, 94). In particular, it was at this time that More began to study the philosophy of Descartes (1596–1650) (Gabbey 1982). Clearly, More was sufficiently aware of developments in natural philosophy to know that Digby’s atomistic system was derivative from, and by no means as powerful as, the Principia philosophiae published in the same year as Digby’s Two Treatises by the great French mathematician turned metaphysician and physicist.