The Doctrine of minima naturalia in the Commentaries on Aristotle’s Physics Attributed to Richard Rufus of Cornwall and Roger Bacon

Abstract This article examines the doctrine of minima naturalia (i.e., the smallest quantity of matter able to preserve the substantial form of a material substance) in three of the earliest extant Latin commentaries on Aristotle’s Physics: the two traditionally ascribed to Roger Bacon (1214/1220–1292), i.e., Questiones supra libros octo Physicorum Aristotelis and Questiones supra libros quatuor Physicorum Aristotelis, and the anonymous In Physicam Aristotelis, which Rega Wood attributes to Richard Rufus of Cornwall (fl. 1231–1256). The position presented by Bacon in Questiones supra libros octo Physicorum displays striking similarities with the one adopted by the author of In Physicam Aristotelis, but also important differences. Moreover, the fact that the view defended in Questiones supra libros quatuor Physicorum is openly rejected in Questiones supra libros octo Physicorum provides additional support to Silvia Donati’s hypothesis that the former is not an authentic work by Bacon.