 In the Latin tradition, direct commentary on Aristotle remained central to most higher education until late in the seventeenth century  (§5.2),  but Arabic authors stopped commenting on his works directly after the twelfth century, and earlier outside Spain. Instead, they began to comment on Avicenna’s rethinking of Aristotle  (§2.3,  §2.10). Commentaries on his work continued to be written, but added to them were, successively, commentaries on later writers who had themselves rethought and rewritten Avicenna’s expositions. Islamic scholars saw commentary as a way of thinking not just on the basis of revered old texts, but on that of the best recent  textbooks.[5]  Although this constant replacement of texts to be commented was foreign to the Latin tradition, three medieval Latin texts were themselves vehicles for many commentaries. The two set texts in the university theology faculties  (§2.7)  were the Bible and a work written circa 1155 by Peter the Lombard, the Sentences, where he set out systematically all the problematic questions in theology and proposed solutions, quoting extensively from Augustine (Evans and Rosemann 2002–14). Much of the best theological and philosophical work in the period from 1250–1550 was done in commentaries on the Sentences, but usually the Lombard’s text was just the springboard for debate. Peter of Spain’s popular logical  Treatise (§4.2)  received commentaries, as did the greatest philosophical poem of the period, Dante’s Commedia Divina  (§2.8).[6]