Intensio and Remissio

Starting from the fourteenth century, “intension” (intensio) and “remission” (remissio) became terms linked to the philosophical attempt at quantifying qualitative changes. Although this attempt proved to some extent useful for the seventeenth-century emergence of a mathematized study of motion, its scope can only be understood within a frame of reference where “motion” has a broad, Aristotelian, sense. Also, intension and remission did not pertain to natural philosophy only – in fact, their meaning grew in philosophical importance within the purview of theology, metaphysics, and medicine. The doctrine of intension and remission has been hitherto studied especially with relation to late middle ages. Some studies have shed light on single instances of Renaissance developments, but a comprehensive study in this regard is yet to be done. A possibly deeper lacuna affects the study of its eighteenthcentury legacy. This being the case, the entry is meant to provide the essential coordinates to contextualize Renaissance contributions to intension and remission. The latter are considered in three aspects: university teach- ing; Aristotelian and non-Aristotelian criticisms; natural philosophy and medicine.