Early in the 13th century we find various controversies at Paris on subjects very like those debated by the Arabic philosophers, but in reality derived from quite independent sources. Nothing would seem more suggestive of Arabic influence than discussion of the essential unity of souls, which seems as though it were an echo of Ibn Rushd; but this doctrine had been developed independently from neo-Platonic material in the Celtic church, and, in its main features not at all unlike the teaching of Ibn Rushd, was fairly common in Ireland (cf. Rènan: Averroes, 132-133). So we find Ratramnus of Corbey in the 9th century writing against one Macarius in refutation of similar views. Here Arabic influence is out of the question; at the time, indeed, Ibn Rushd was not yet born. So of Simon of Tournay, who was a teacher of theology at Paris about 1200 A.D., we read that “whilst he follows Aristotle too closely, he is by some recent writers accused of heresy” (Henry of Gand: Lib. de script. eccles. c. 24 in Fabrisius Bibliotheca, 2, p. 121), but this simply means that he carried to an extreme the application of the dialectical method to theology.
More interest attaches to the decrees passed at a synod held at Paris in 1209 and endorsed by the decisions of the Papal Legate in 1215. These measures were provoked by the pantheistic teaching of David of Dinant and Amalric of Bena, who revived the semipantheistic doctrines of John Scotus’ Periphysis, and the prohibitions dealing with them cite passages from Scotus verbatim. The Periphysis itself was condemned by Honorius III. in 1225. But the decrees of 1209 also forbade the use of Aristotle’s Natural Philosophy and the “commenta,” whilst the Legate’s orders of 1215 allowed the logical works of the old and new translations where perhaps the “new translations” refers to the “new” translations made from the Arabic as contrasted with the “old” versions of Boethius, though it is just possible that some version direct from the Greek was in circulation and known as the “new translations,” and also forbade the reading of the Metaphysics, Natural Philosophy, etc., all material which had become accessible through the Arabic.
In 1215 Frederick II. became Emperor, and in 1231 he began to reorganize the kingdom of Sicily. Both in Sicily and in the course of his crusading expeditions in the East Frederick had been brought into close contact with the Muslims and was greatly attracted to them. He adopted oriental costume and many Arabic customs and manners, but, most important of all, he was a great admirer of the Arabic philosophers, whose works he was able to read in the original, as he was familiar with German, French, Italian, Latin, Greek, and Arabic. Contemporary historians represent him as a free-thinker, who regarded all religions as equally worthless, and attributed to him the statement that the world had suffered from three great imposters, Moses, Christ, and Muhammad. This opinion of Frederick is expressed in passionate words by Gregory IX. in the encyclical letter “ad omnes principes et prelatos terrae” (in Mansi. xxiii. 79), where he compares the Emperor to the blaspheming beast of Apocalypse xiii., but Frederick in reply likened the Pope to the beast described in Apoc. vi., “the great dragon which reduced the whole world,” and professed a perfectly orthodox attitude towards Moses, Christ, and Muhammad. It is quite probable, as Rènan (Averroes, p. 293) supposes, that the views ascribed to Frederick really are based on a professed sympathy towards the Arabic philosophers, who regarded all religions as equally tolerable for the uninstructed multitude, and commonly illustrated their remarks by citing the “three laws” which were best known to them. In 1224 Frederick founded a university at Naples, and made it an academy for the purpose of introducing Arabic science to the western world, and there various translations were made from Arabic into Latin and into Hebrew. By his encouragement Michael Scot visited Toledo about 1217 and translated Ibn Rushd’s commentaries on Aristotle’s de coelo et de mundo, as well as the first part of the de anima. It seems probable also that he was the translator of commentaries on the Meteora, Parva Naturalia, de substantia orbis, Physics, and de generatione et de corruptione. Ibn Sina’s commentaries were in general circulation before this, so that they were very probably the “commentaries” referred to in the Paris decree of 1209, but we do not know who was responsible for their rendering into Latin, save that they almost certainly proceeded from the college at Toledo. The introduction of Ibn Rushd, not of great repute amongst the Muslims, bears evidence to the weight of Jewish influence in Sicily and in the new academy at Naples. We know that Michael Scot was assisted by a Jew named Andrew.
Another translator of this period was a German Hermann who was in Toledo about 1256, after Frederick’s death. He translated the abridgment of the Rhetoric made by al-Farabi, Ibn Rushd’s abridgment of the Poetics, and other less known works of Aristotle. Hermann’s translations were described by Roger Bacon as barbarous and hardly intelligible; he transliterated the names so as to show even the tanwin in Ibn Rosdin, abi Nasrin, etc.
By the middle of the 13th century nearly all the philosophical works of Ibn Rushd were translated into Latin, except the commentary on the Organon, which came a little later, and the Destruction of the Destruction, which was not rendered into Latin until the Jew Kalonymos did so in 1328. Some of his medical works also were translated in the 13th century, namely, the Colliget, as it was called, and the treatise de formatione; others were translated from the Hebrew into Latin early in the following century.
The first evidence of the general circulation of ideas taken from Averroes (Ibn Rushd) is associated with William of Auvergne, who was Bishop of Paris, and these show a considerable amount of inaccuracy in detail. In 1240 William published censures against certain opinions, which he states to be derived from the Arabic philosophers; amongst these he expresses his disapproval of the doctrine of the First Intelligence, an emanation from God, as being the agent of creation, a doctrine common to all the philosophers, but which he attributes specifically to al-Ghazali; he objects also to the teaching that the world is eternal, which he attributes correctly to Aristotle and Ibn Sina, but mentions Averroes as an orthodox defender of the truth; he further condemns the doctrine of the unity of intellects, which most incorrectly he attributes to Aristotle, and also refers to al-Farabi as maintaining this heresy; throughout he cites Averroes as a sounder teacher who tends to correct these ideas, but his description of the doctrine of the unity of intellects reproduces the features which are distinctive of Averroes. The arguments he uses against this latter doctrine are, on the whole, very much the same as those employed a little later by Albertus Magnus and St. Thomas, viz., that the doctrine undermines the reality of the individual personality, and is inconsistent with the observed facts of diversity of intelligence in different persons. He cites Abubacer (Ibn Bajja) as a commentator on Aristotle’s Physics, but in fact this was a book on which Ibn Bajja did not write a commentary, and the substance of the citation agrees with the teaching of Averroes. At that time evidently the position was that Aristotle and the Arabic commentators generally were regarded with suspicion save in the treatment of logic, the one exception being Averroes, who was considered to be perfectly orthodox. So strange a perversion of the facts could only be due to Jewish influence, for the Jews at that time were devoted adherents of Averroes.
When the friars began to take their place in the work of the universities we note two striking changes: (i.) the friars cut loose entirely from the timid policy of conservatism and begin to make free use of all the works of Aristotle and of the Arabic commentators, and also make efforts to procure newer and more correct translations of the Aristotelian text from the original Greek; under this leadership the universities gradually became more modern and enterprising in their scientific work, though not without evidence of strong opposition in certain quarters. (ii.) As a natural corollary a more correct appreciation was made of the tendencies of the several commentators.
The leader in these newer studies was the Franciscan Alexander Hales (d. 1245), who was the first to make free use of Aristotle outside the logical Organon. His Summa, which was left unfinished and continued by the Franciscan William of Melitona, was based on the Sentences of Peter Lombard, and serves as a commentary to it. Peter Lombard, however, had not quoted Aristotle at all, whilst Alexander uses the metaphysical and scientific works as well as the logic. From this time forth the Franciscans begin to use the Arabic commentators.
The more accurate study of Aristotle in mediæval scholasticism begins with Albertus Magnus (1206-1280), the Dominican friar who first really perceived the importance of careful and critical versions of the text, and thus introduced a strictly scientific standard of method. He studied at Padua, a daughter university of Bologna, but became a Dominican in 1223. His methods were followed and developed by his pupil, St. Thomas Aquinas (d. 1274), who arranged his work on the lines already indicated in Albertus’ commentary on Aristotle’s Politics, lines which became the regulation method in Latin scholastic writers, and he was at pains to get new translations made directly from the Greek, which was now freely accessible; a new translation direct from the Greek was made by William de Moerbeka at the request of St. Thomas. But there is a significant change from the time when Albertus delivered his lectures: in the work of Albertus the commentator chiefly used was Ibn Sina, but in that of St. Thomas there is a free use of Averroes (Ibn Rushd), although St. Thomas shows that he is perfectly well aware of the peculiar doctrines held by this latter philosopher, and guards himself carefully from them.
St. Thomas frequently enters into controversy with the Arabic commentators, and especially attacks the doctrines (i.) that there was a primal indefinite matter to which form was given at creation (cf. Summa. lae quaes. 66, art. 2); (ii.) that there were successive series of emanations, a doctrine which had now assumed an astrological character; (iii.) that the Agent Intellect was the intermediary in creation (cf. Summa. 1, 45, 5; 47, 1; 90, 1); (iv.) that creation ex nihilo is impossible; (v.) that there is not a special providence ruling and directing the world; and (vi.) most of all, the doctrine of the unity of intellects, a doctrine which, as he shows, is not to be found in Aristotle, Alexander of Aphrodisias, Avicenna, or Ghazali, but is a speculative theory of Averroes alone, at least in the form then becoming popular as pampsychism. All these objections were essentially the same as had been already brought forward by the orthodox scholastics of Islam, and undoubtedly al-Ghazali is used in refuting them. According to St. Thomas, the doctrine of pampsychism is entirely subversive of human personality and of the separate individuality of the ego, to which our own consciousness bears witness. God creates the soul for each child as it is born; it is no emanation, but has a separate and distinct personality. As a corollary he denies the ittisal or final “union,” which involves the reabsorption of the soul in its source.