Abstract

In a long question, "Whether there is motion to quality," which became part of his Oxford Expositio omnium librorum Physicorum cum questionibus optime disputatis, composed before 1310, Walter Burley supported the succession-of-forms theory of qualitative change. After commenting on Peter Lombard's Sentences at Paris, Burley took part in disputations on controversial questions in the early 1320s, resulting in his De primo et ultimo instanti and his Tractatus Primus and Tractatus Secundus de intensione et remissione formarum. In these independent controversial works, Burley advanced and defended the succession-of-forms theory with greater detail and precision. This paper examines the treatment of the mathematics of alteration in Burley's final Parisian Expositio in libros octo de physico auditu in light of this earlier controversial work