It was this theory which Averroes (1126-1198), the last and most famous of the thinkers of Moslem Spain, carried out to his doctrine of the unity of intellect. The whole doctrine will be discussed under the heading AVERROES; but its general purport is this. Reproducing, on one hand, the customary psychology of Aristotle as it rises gradually from the mere sense to the understanding, it emphasizes, on another hand, the permanent subsistence and action of intellect apart from all materiality and from the individuals who share in the intellectual power. In the active intellect it finds the motive principle, and the full fruition of human reason. Sometimes this intellect is invested with the supremacy of the sphere beneath the moon, and connected with a more universal intelligence through a hierarchy of spiritual principles in the celestial system. Such a mind is the sole actual intellect in which the generations of thinking men live and move. In complete union with it lies their perfect beatitude; and, save as a temporary participant in the blessings of this universal form, the intellectual soul is a nonentity.
The philosophers thus characterized were in almost every case physicians; and with their medical knowledge they frequently combined studies in mathematics, astronomy, and alchemy. In all these departments they were the pupils of Greeks, text they accepted almost as a revelation. Their talent lay in the elaboration of details, and in correcting certain mistakes of their guides; but they never introduced any comprehensive change. Still their conjunct prosecution of physical and metaphysical studies gave them an advantage over their Latin contemporaries, with whom the schools of dialetic grew into exaggerated prominence, whilst few traces were left, as a Salerno, of the medical and scientific pursuits of the ancient world. Their acquaintance with art was another feature in favour of the Arabians. Al-Kendi, Al-Farabi, and Ibn-Badja were musicians of note: Ibn-Tofail and Ben-Gebirol were famous as poets. Their studies in the sacred law and in theology did not unduly dominate their philosophical investigations, and they combined much practical work as physicians and statesmen with an almost incredible industry in appropriating and systematizing the wisdom of Greece. But the great education value of Arabian philosophy for the later schoolmen consisted in its making them acquainted with an entire Aristotle. At the moment when it seemed as if everything had been made that could be made out of the fragments of Aristotle, and the compilations of Capella, Cassiodorus, and others, and when mysticism and skepticism seemed the only resources left for the mind, the horizon of knowledge was suddenly widened by the acquisition of a complete Aristotle. Thus the mistakes inevitable in the isolated study of an imperfect Organon could not henceforth be made. The real bearing of old questions, and the meaninglessness of many disputes, were seen in the new conception of Aristotelianism given by the Metaphysics, and other treatises. The former Realism and Nominalism were lifted into a higher phase by the principle of the universalizing action of intellect - (Intellectus in formis agit universalitatem). The commentaries of the Arabians in this respect supplied nutriment more readily assimilated by the pupils than the pure text would have
Arabian philosophy, whilst it promoted the exegesis of Aristotle and increased his authority, was not less notable as the source of the separation between theology and philosophy. Speculation fell on irreligious paths. In many cases the heretical movement was due less to foreign example than to the indwelling tendencies of the dominant school of Realism. But it is not less certain that the very considerable freedom of the Arabians from theological bias served indirectly to intensity the prevailing protest against Sacerdotalism, and prepared the time when philosophy shook off its ecclesiastical vestments. In the hurry of first terror, the struck Aristotle with the anathema launched against innovations in philosophy. The provincial council of Paris in 1209, which condemned Amalricus and his followers, as well as David of Dinant's works, forbade the study of Atistotle's Natural Philosophy, and the Commentaries. In 1215 the same prohibition was repeated, specifying the Metaphysics and Physics, and the Commentaries by the Spaniard Mauritius (i.e. probably Avveroes). Meanwhile Albertus Magnus and Thomas Aquinas, accepting the exegetical services of the Arabians, did their best to controvert the obnoxious doctrine of the Intellect, and to defend the orthodoxy of Aristotle against the unholy glosses of infidels. But it is doubtful whether even they kept as pure from the infection of illegitimate doctrine as they supposed. The tide meanwhile flowed in stronger and stronger. In 1270 Stephen Tempier, bishop of Paris, supported by an assembly of theologians, anathematized thirteen propositions bearing the stamp of Arabian authorship; but in 1277 the same views and others more directly offensive to Christians and theologians had to be censured again. Raymond Lyllu, in a dialogue with an infidel thinker, broke a lance in support of the orthodox doctrine, and carried on a crusade against the Arabians in every university; and a disciple of Thomas Aquinas drew up a list (De Erroribus philosophorum) of the several delusions and errors of each of the thinkers from Alkindius to Averroes. Strong in their conviction of the truth of Aristotelianism, the Arabians carried out their logical results in the theological field, and made the distinction of necessary and possible, of form and matter, the basis of conclusions in the most momentous questions. They refused to accept the doctrine of creation because it conflicted with the explanation of forms as the necessary evolution of matter. They denied the particular providence of God, because knowledge in the divine sphere did not descend to singulars. They excluded the Deity from all direct action upon the world, and substituted for a cosmic principle the active intellect,-thus holding a form of Pantheism. But all did not go the same length in their divergence from the popular creed.
The half-legendary accounts which attribute the intro duction of Arabian science to Gerbert, afterwards Pope Sylvester II., to Constantinus Africanus, and to Adelard of Bath, if they have any value, refer mainly to medical science and mathematics. It was not till about the middle of the 12th century that under the patronage of Raymond, archbishop of Seville, a society of translators, with the archdeacon Dominicus Gundisalvi at their head, produced Latin versions of the Commentaries of Avicenna and Algazel, of the Fons Vitoe of Avicebron, and of several Aristotelian treatises. The working translators were converted Jews, the best known among them being Joannes Avendeath. With this effort began the chief translating epoch for Arabic works. Avicenna's Canon of Medicine was first translated into Latin by Gerard of Cremona (d. 1187), to whom versions of other medical and astronomical works are due. The movement towards introducing Arabian science and philosophy into Europe, however, culminated under the patronage of the Emperor Frederick II. (1212-1250). Partly from superiority to the narrowness of his age, and partly in the interest of his struggle with the Papacy, this Malleus ecclesioe Romanoe drew to his court those savants whose pursuits were discouraged by the church, and especially students in the forbidden lore of the Arabians. He is said to have pensioned Jews for purposes of translation. One of the scholars to whom Frederick gave a welcome was Michael Scot, the first translator of Averroes. Scot had sojourned at Toledo about 1217, and had accomplished the versions of several astronomical and physical treatises, mainly, if we believe Roger Bacon, by the labours of a Jew named Andrew. But Bacon is apparently phypercritical in his estimate of the translators from the Arabic. Another protxgé of Frederick's was Hermann the German (Alemannus), who, between the years 1243 and 1256, translated amongst other things a paraphrase of Al-Farabi on the Rhetoric, and of Averroes on the Poetics and ethics of Aristotle. Jewish scholars held an honourable place in transmiting the Arabian commentators to the schoolmen. It was amongst them, especially in Maimonides, that Aristotelianism found refuge after the light of philosophy was extinguished in Islam; and the Jewish family of the Ben-Tibbon were mainly instrumental in making Averroes known to southern France.