Sennert and the Unity of Nature

Daniel Sennert (1572-1637), a Wittenberg professor of medicine in Wittenberg for over 30 years, is firmly rooted in the Aristotelian tradition. At the same time, Sennert is also an atomist, one of the doctrines most fervently combated by Aristotle. Sennert harmonizes the two positions by claiming that Aristotle’s central concept, the substantial form, extends to the atoms as well. To articulate this idea, he draws on a variety of influences: the medical tradition, the chemical theories of the Paracelsians and multiple different strands of scholastic Aristotelianism. Sennert’s medical and chemical ideas have been studied recently, but not their relation to his conception of natural philosophy.

Despite his atomism, Sennert always remained committed to the fundamental tenets of Aristotelianism. The paper will argue that it is precisely because of this conservative streak that his changes in the conception of the substantial form leads to a transformation of what can actually be explained in natural philosophy. In this way, Sennert’s gentle modification of Aristotle does change the discipline of natural philosophy after all.