This text, the Questions concerning Aristotle's On Animals [Quaestiones super de animalibus], recovered only at the beginning of the twentieth century and never before translated in its entirety, represents Conrad of Austria's report on a series of disputed questions that Albert the Great addressed in Cologne ca. 1258.

This work is the first English translation of Scotus's commentary on Aristotle's Quaestiones super Praedicamenta. Although there are numerous Latin commentaries on Aristotle's Categories, Scotus's Questions is one of the few commentaries on the Categories written in the thirteenth century covering all of Aristotle's text, including the often neglected post-praedicamenta, and the only complete Latin commentary available in English. Moreover, unlike many of the commentaries, Scotus's text is one of the last commentaries to be written before the nominalist reduction of the categories to substance and quality. The question format allows Scotus a great deal of liberty to discuss the categories in detail, as well as matters that are only remotely raised by the text. Altogether, the forty-four questions cover the following subjects: questions 1-4 are prolegomena to the work itself and raise the question of its subject matter as well as whether there can be a science of the categories; questions 5-8 deal with equivocals, univocals, and denominatives; questions 9-11 discuss Aristotle's two rules regarding predication and the sufficiency of the categories; questions 12-36 discuss the four main categories treated by Aristotle, namely, substance, quantity, relation, and quality; and the remaining eight questions discuss the post-praedicamenta.