Anneliese Maier: Galileo and Theories of Impetus

Abstract

In one of her late essays Anneliese Maier took up a theme that had interested her throughout a good part of her life and attempted to clarify, once again, the extent to which Galileo was indebted to fourteenth-century theories of impetus for the elaboration of his “new science” of motion (1967, pp. 465–490).¹ In the course of her exposition she pointed out how Galileo’s concept of impetus changed from his earliest writings on motion to his more mature works, but that even when such changes are taken into account, the way in which he thought of impetus was quite different from the view of the four-teenth-century Scholastics. She also raised a question about his reading of Aristotle’s texts bearing on this subject, suggesting that he might have gotten his knowledge of Aristotle “at second hand,” and so implying that the ideas about impetus being entertained in the latter part of the sixteenth century were different from those that were current in the fourteenth century (ibid., p. 468). Regardless of how Galileo came by his understanding of impetus, however, Maier contended that even his earlier view was closer than the medievals’ to the modern concept of inertia, and thus that it was easier for him to make the transition to the “new science” than it would have been had he well understood and subscribed to the fourteenth-century concept (ibid., pp. 468–469).