ARABIAN AND JEWISH PHILOSOPHY Arabian and Muslim Philosophy.—When the Athenian schools of philosophy were closed in 529 many of the teachers migrated to Syria and Persia and stimulated philosophical interest in the Muslim world. This interest was intensified when in 641 the Arabs captured Alexandria, which was then the greatest seat of learning, with a long and honourable tradition behind it. By 711 the Muslims had swept through Arabia, Syria and Meso potamia, and even along the African coast of the Mediterranean as far as the straits of Gibraltar, and went into Spain. (The "Moors" of Spain were Arabs from Mauretania, that is, North Africa.) In this way philosophy was kept alive in Islam and in due course brought back to Christendom. The most important Muslim philosophers were Al Kindi (d. 87o), Alfarabi (d. 95o) and Avicenna, or Ibn Sina (98o-1o37) of Baghdad, and Averroes (1126-1198) of Cordova, in Spain. They were familiar with nearly all the works of Aristotle, and with several of Plato's trea tises. Their philosophy was Aristotelian in the main, but blended with Platonism. The most interesting feature in Avicenna is his discussion of the problem which subsequently became one of the most burning questions among the Christian Scholastics, namely, the problem of the relation of the universal to the particulars of which it is predicated—the bone of contention between the so-called Nominalists and Realists of Scholasticism. And his solution was this. Universals existed in the thought of God already before the corresponding particulars came into existence ; but they were then embodied in the particulars ; and are derived by the human mind from these by a process of abstraction.
Averroes was the most Aristotelian of all the Muslim philoso phers, and the most important. According to Averroes, there is a sub-lunar world of imperfection and change, and another, higher, eternal world beyond the stars. Matter is eternal, and contains from the first certain seminal "forms" which develop it from the merely potential to the actual, or final, state, under the influence of the higher "forms," or "intelligences," or in the last resort, of God. The human soul is inseparable from the body, or rather the brain, and perishes with it ; but the "reason" that dwells in man is immortal, and by cultivating it man may enter into union with the universal "active reason." (See ARABIAN PHILOSOPHY.) Jewish Philosophy.—Already in pre-Christian times there existed among the Jews a kind of philosophical mysticism which resembled Neo-Platonism in some respects. It is possible that Philo, the Jewish founder of Neo-Platonism, came under its influ ence at one time. This mystical doctrine is known as the Kabbalah
(Hebrew for "traditional lore"). But it is difficult to trace its history with accuracy, as its two principal documents—the Sepher Yetzirah ("Book of Creation") and the Zohar ("Book of Splen dour")—are compilations which are not much earlier than goo and 130o respectively. Side by side with this movement, however, there grew up, a more genuine philosophy under the influence of Plato and Aristotle. This movement had two interesting periods, namely, the Alexandrian period, about the beginning of the Christian era, in which Philo and various other Egyptian Jews flourished, and the Spanish period, from about the loth till the 14th century, when many Jews vied with the Moors in the cultivation of Platonic and Aristotelian philosophy.
The favourable conditions under which Jews lived, during these centuries, throughout the Muslim world encouraged their par ticipations in the interest which Islam then took in philosophy. In Baghdad and in Cairo, in Cordova and Toledo, they kept abreast of their Muslim neighbours. Numerous as were the Mohammedan schools and sects produced by the study of Greek philosophy, almost every one of them was reflected in contempo rary Jewish thought. Traditionalism and anti-traditionalism, rationalism and dogmatism, fatalism and voluntarism, Platon ism and Aristotelianism—all these and other tendencies had their Jewish counterparts, and almost every Muslim philosopher of repute had his Jewish double. This does not argue imitation but a similar susceptibility to similar influences. During the loth and iith centuries Platonism and Aristotelianism were about equal in favour. The chief Jewish thinkers of this period were Israeli (between 85o and 95o), the author of a treatise On the Elements; Seadiah (892-942), author of Faith and Philosophy; and Bachyah Ibn Pakuda ( ?i000–io5c), who wrote a Guide to the Duties of the Heart. To this period belongs also the Jewish Neo-Pla tonist and poet Ibn Gabirol ( ?Io2o–Io7o), whose Fons Vitae ("Fountain of Life") was probably the first book to re-introduce Greek philosophy into the West after the close of the dark ages. During the 12th century, Aristotelianism gained in influence, and enjoyed almost undisputed supremacy during the 13th and 14th centuries. The most important Jewish thinkers of this period were Maimonides (1135-1204), author of the Guide of the Perplexed; Gersonides (1288-1344) author of The Wars of the Lord; and Crescas (1340-141o), author of The Light of the Lord.