Prime Matter in Descartes and the Late Scholastics

Roger Ariew

University of South Florida

Descartes wrote the Principles of Philosophy as something of a rival to Scholastic textbooks. He initially conceived the project as a comparison of his philosophy and that of the Scholastics, intending the work to be a synopsis of his philosophy arranged in the same order as in the School curriculum, together with a summary of School philosophy; and he chose Eustachius a Sancto Paulo’s Summa Philosophiae Quadripartita for the task—“the best book of its kind ever made.” Descartes abandoned the design in part because he thought Scholastic philosophy was “so absolutely and so clearly destroyed by means of the establishment of [his] philosophy alone, that no other refutation is needed.” His project then transformed into that of the Principles, which does retain some of the flavor of the original design: after a reordered, abbreviated version of the Meditations, Part I of the Principles consists essentially of new materials resembling what Scholastics might have considered in their treatises on metaphysics: definitions of substance, attributes, modes and accidents, duration and time, number, and universals, followed by a theory of distinctions (real, modal, and of reason). I wish to discuss some of these materials and to compare them to what 17th century Scholastics (Eustachius, in particular) asserted in their treatises. Specifically, I ask: what happens to the traditional form-matter pair in the Cartesian program? How does matter get transformed by Descartes? Are there Scholastic precedents for Descartes’ views? The answer at first sight appears simple. Scholastics saw everything—with the possible exception of the human rational soul after death, and of course God—hylomorphically. That is to say, they saw it as matter, itself mere potentiality, informed, or actualized, in such and such ways to produce the nice, tidy variety of things, animate and inanimate, found around us. Within each specific form, matter is the principle of individuation, but in subordination to a form. Descartes changed all that by making matter independent, and replacing form, here and there only, by separate mind. So most of the former hylomorphic cosmos became just spread-out stuff, with minds dotted here and there as God decreed. This, it seems, was the Cartesian revolution: there are two kinds of created substances, distinct from one another, that need only the concurrence of God to exist; we discover them through their principal attributes, thought and extension. For Descartes extension (matter) is independent of mind (form) and subsists without it. Descartes also talks about mind informing or being substantially united to a body. Thus one substance can inform another substance. These Cartesian views do not seem to be compatible with strict hylomorphism. However, by the 17th century, the so-called standard, or Thomistic, view of form and matter had been significantly modified, so that strict hylomorphism no longer prevailed. There were Scotist positions everywhere which caused the Cartesian views not to look as strange as they might have from a Thomistic point of view.