Philosophical works.  Grosseteste composed a number of short philosophical works. On Light (De luce) his minor masterpiece, develops his so-called light metaphysics; it appears to be the object of cross-references in his commentaries on Aristotle and thus written prior to them. Closely related to On Light is a short work On Bodily Movement and Light (De motu corporali et luce). Other short philosophical works are On Potency and Act (De potentia et actu), On the Halt of Causes (De statu causarum), On the Subsistence of a Thing (De subsistentia rei), and On the Truth of the Proposition (De veritate propositionis).  On the Finitude of Movement and Time (De finitate motus et temporis) (a longer version of which is appended to the commentary on the Physics) attacks Aristotle’s arguments for the infinitude of past time and movement; it was probably written in the 1230s