It is worth noting that St. Thomas received his education before joining the Dominican order in the university of Naples, which had been founded by Frederick II. and was a centre of interest in the Arabic philosophers, and this probably goes far to account for his more accurate appreciation of their teaching. Unquestionably St. Thomas Aquinas must be regarded as the prince of the Latin scholastics, for it is he who first draws freely upon metaphysics and psychology and co-ordinates them with theology—the psychological analysis given in the Secunda secundae of the Summa is one of the best products of the Latin scholastics—and also he was the first to appreciate correctly the difficulties of translation and insist on an accurate rendering as essential to an understanding of Aristotle. For the most part, as we have noted, the mediæval scholars undervalued the translator’s task and were content with a hack interpreter, and saw no reason for applying themselves to the study of the original text, a view in which the Arabic philosophers shared. Incidentally St. Thomas was the first who makes free use of all the Arabic commentators and shows that he is fully aware of their defects. Undoubtedly he regarded Averroes as the best exponent of the Aristotelian text, and the supreme master in logic, but heretical in his metaphysics and psychology.
About 1256 Averroes’ teaching about the unity of intelligences was sufficiently widespread at Paris to induce Albertus to write his treatise “On the unity of the intellect against the Averroists,” a treatise which he afterwards inserted in his Summa. In 1269 certain propositions from Averroes were formally condemned. At this time his works were well known, and there was a distinct party at Paris which had adopted his views and which we may describe as a semi-Judaistic party. This time both Albertus and St. Thomas published treatises against the doctrine of the unity of intelligences.
Again in 1277 various Averroist theses were condemned at Paris, for the most part emanating from the Franciscans, who, as Bacon notes (opus Tert. 23), were strongly inclined towards Averroes both at Paris and in England, a condition which prevailed until the great Franciscan doctor Duns Scotus (d. 1308) took a definitely anti-Averroist line. Still, even in the 14th century, when Averroism was practically dead at Paris, it still retained its hold amongst the Franciscans in the English “nation.”
The Dominicans were less favourably disposed towards the Arabic writers, at least after the time of Albertus, and show a much more careful estimate of their work. This was no doubt due to the fact that they had a house of Arabic studies in Spain, and were actually engaged in controversy with the Muslims. As a rule a careful distinction is drawn between Averroes the commentator, who is treated with great respect as an exponent of the text of Aristotle, and Averroes the philosopher, who is regarded as heretical. It seems as though there was a deliberate policy to secure Aristotle by sacrificing the Arabic commentators. Very characteristic of the work of the Dominicans was the Pugio Fidei adversum Mauros et Judaeos of Raymund Martini, who lived in Aragon and Provence; he was familiar with Hebrew, and freely uses the Hebrew translations of the Arabic philosophers. His arguments are largely borrowed from al-Ghazali’s Destruction of the Philosophers. It is curious to note that, in his anxiety to defend Aristotle, he accuses Averroes of borrowing the doctrine of the unity of intelligences from Plato, and in a sense there was an element of truth in this, for the Averroist doctrine was ultimately derived from neo-Platonic sources. Raymund also cites the medical teaching of Averroes at a date earlier than any Latin version, and here again shows familiarity with the Hebrew translations.
John Baconthorp (d. 1346), the provincial of the English Carmelites and “doctor” of the Carmelite order, tends to palliate the heretical tendencies of Averroes’ teaching, and was called by his contemporaries “the prince of Averroists,” a title which was apparently regarded as a compliment.
Amongst the Augustinian friars Giles of Rome in his de Erroribus Philosophorum was an opponent of the teaching of Averroes, especially attacking the doctrine of the unity of souls and the union or ittisal, but Paul of Venice (d. 1429), of the same order, shows a tendency favourable to Averroism in his Summa.
The 13th century had generally used Ibn Sina (Avicenna) as a commentator on Aristotle, but in the 14th century the general tendency was to prefer Averroes, who was regarded as the leading exponent of the Aristotelian text even by those who disapproved his teaching.
The University of Montpelier as a centre of medical studies might be expected to use the Arabic authorities, but this university, though traditionally founded by Arabic physicians driven out of Spain, was re-founded as a distinctly ecclesiastical institution in the 13th century, and became the home of Greek medical studies based on Galen and Hippocrates, though probably the earlier texts in use were translated from the Arabic versions. To this more wholesome Greek character the university remained faithful, and there was always a tendency at Montpelier to regard the Arabic use of talismans and astrology in medicine as heretical. It was not until the beginning of the 14th century that the Arabic medical writers began to be used there at all, and they remained in quite a secondary rank. In 1304 Averroes’ Canones de medicinis laxativis was translated from the Hebrew, and in 1340 we find that i. and iv. of the Canons of Avicenna are included in the official syllabus set for candidates for medical degrees, and from this time forward the lectures include courses on the Arabic physicians. In 1567 the Arabic medical works were definitely struck off the list of books required for examination in the schools at the petition of the students, but occasional lectures on the Canons of Avicenna were given down to 1607.
The real home of Averroism was the University of Bologna, with its sister University of Padua, and from these two centres an Averroist influence spread over all N.E. Italy, including Venice and Ferrara, and so continued until the 17th century. It was a precursor of the rationalism and anti-church feeling of the renascence, perhaps assisted by Venetian contact with the East. At Bologna Arabic influence was predominant in medicine; already in the later 13th century the medical course centres in the Canon of Avicenna and the medical treatises of Averroes, with the result that astrology became a regular subject of study, and degrees were granted in it. Most of the physicians of Bologna and Padua were astrologers, and were generally regarded as free-thinkers and heretics. Bologna had at one time enjoyed the favour of Frederick II., and he had presented the University with copies of the Latin translations prepared by his order from Arabic and Greek.