The second factor conducing to mental advancement was the schools which have flourished in Israel since the days of the prophet Samuel; and the third was the linguistic attainments of the Jews, which they owed to natural ability in this direction. Scarcely had Greek allied itself with Hebrew thought, when Jews in Alexandria wrote Greek comparable with Plato's, and not more than two hundred years after the settlement of Jews in Arabia we meet with a large number of Jewish poets among Mohammed's disciples, while in the middle ages they taught and wrote Arabic, Spanish, French, and German—versatility naturally favorable to intellectual progress.

Jewish influence may be said to have begun to exercise itself upon general culture when Judaism and Hellenism met for the first time. The result of the meeting was the new product, Judæo-Hellenic literature. Greek civilization was attractive to Jews. The new ideas were popularized for all strata of the people to imbibe. Shortly before the old pagan world crumbled, Hellenism enjoyed a beautiful, unexpected revival in Alexandria. There, strange to say, Judaism, in its home antagonistic to Hellenism, had filled and allied itself with the Greek spirit. Its literature gradually adopted Greek traditions, and the ripe fruit of the union was the Jewish-Alexandrian religious philosophy, the mediation between two sharply contradictory systems, for the first time brought into close juxtaposition, and requiring some such new element to harmonize them. When ancient civilization in Judæa and in Hellas fell into decay, human endeavor was charged with the task of reconciling these two great historical forces diametrically opposed to each other, and the first attempt looking to this end was inspired by a Jewish genius, Jesus of Nazareth.

The Jews of Alexandria were engaged in widespread trade and shipping, and they counted among them artists, poets, civil officers, and mechanics. They naturally acquired Greek customs, and along with them Hellenic vices. The bacchanalia of Athens were enthusiastically imitated in Jerusalem, and, as a matter of course, in Alexandria. This point reached, Roman civilization asserted itself, and the people sought to affiliate with their Roman victors, while the rabbis devoted themselves to the Law, not, however, to the exclusion of scientific work. In the ranks of physicians and astronomers we find Jewish masters and Jewish disciples. Medicine has always been held in high esteem by Jews, and Samuel could justly boast before his contemporaries that the intricate courses of the stars were as well known to him as the streets of Nehardea in Babylonia.[22]

The treasures of information on pedagogics, medicine, jurisprudence, astronomy, geography, zoology, botany, and last, though not least, on general history, buried in the Talmud, have hitherto not been valued at their true worth. The rabbis of the Talmud stood in the front ranks of culture. They compiled a calendar, in complete accord with the Metonic cycle, which modern science must declare faultless. Their classification of the bones of the human body varies but little from present results of the science of anatomy, and the Talmud demonstrates that certain Mishna ordinances are based upon geometrical propositions, which could have been known to but few mathematicians of that time. Rabbi Gamaliel, said to have made use of a telescope, was celebrated as a mathematician and astronomer, and in 289 C. E., Rabbi Joshua is reported to have calculated the orbit of Halley's comet.

The Roman conquest of Palestine effected a change in the condition of the Jews. Never before had Judah undergone such torture and suffering as under the sceptre of Rome. The misery became unendurable, and internal disorders being added to foreign oppression, the luckless insurrection broke out which gave the deathblow to Jewish nationality, and drove Judah into exile. On his thorny martyr's path he took naught with him but a book—his code, his law. Yet how prodigal his contributions to mankind's fund of culture!

About five hundred years later Judah saw springing up on his own soil a new religion which appropriated the best and the most beautiful of his spiritual possessions. Swiftly rose the vast political and intellectual structure of Mohammedan power, and as before with Greek, so Jewish thought now allied itself with Arabic endeavor, bringing forth in Spain the golden age of neo-Hebraic literature in the spheres of poetry, metaphysical speculation, and every department of scientific research. It is not an exaggerated estimate to say that the middle ages sustained themselves with the fruit of this intellectual labor, which, moreover, has come down as a legacy to our modern era. Two hundred years after Mohammed, the same language, Arabic, was spoken by the Jews of Kairwan and those of Bagdad. Thus equipped, they performed in a remarkable way the task allotted them by their talents and their circumstances, to which they had been devoting themselves with singular zeal for two centuries. The Jews are missioned mediators between the Orient and the Occident, and their activity as such, illustrated by their additions to general culture and science, is of peculiar interest. In the period under consideration, their linguistic accomplishments fitted them to assist the Syrians in making Greek literature accessible to the Arabic mind. In Arabic literature itself, they attained to a prominent place. Modern research has not yet succeeded in shedding light upon the development and spread of science among the Arabs under the tutelage of Syrian Christians. But out of the obscurity of Greek-Arabic culture beginnings gleam Jewish names, whose possessors were the teachers of eager Arabic disciples. Barely fifty years after the hosts of the Prophet had conquered the Holy Land, a Jew of Bassora translated from Syriac into Arabic the pandects by the presbyter Aaron, a famous medical work of the middle ages. In the annals of the next century, among the early contributors to Arabic literature, we meet with the names of Jews as translators of medical, mathematical, and astronomical works, and as grammarians, astronomers, scientists, and physicians. A Jew translated Ptolemy's "Almagest"; another assisted in the first translation of the Indian fox fables (Kalila we-Dimna); the first furnishing the middle ages with the basis of their astronomical science, the second supplying European poets with literary material. Through the instrumentality of Jews, Arabs became acquainted as early as the eighth century, some time before the learning of the Greeks was brought within their reach, with Indian medicine, astronomy, and poetry. Greek science itself they owed to Jewish mediation. Not only among Jews, but also among Greeks, Syrians, and Arabs, Jewish versatility gave currency to the belief that "all wisdom is of the Jews," a view often repeated by Hellenists, by the "Righteous Brethren" among the Arabs, and later by the Christian monks of Europe.

The academies of the Jews have always been pervaded by a scientific spirit. As they influenced others, so they permitted the science and culture of their neighbors to act upon their life and work. There is no doubt, for instance, that, despite the marked difference between the subjects treated by Arabs and Jews, the peculiar qualities of the old Arabic lyrics shaped neo-Hebraic poetry. Again, as the Hebrew acrostic psalms demonstrably served as models to the older Syrian Church poets, so, in turn, Syriac psalmody probably became the pattern synagogue poetry followed. Thus Hebrew poetry completed a circuit, which, to be sure, cannot accurately be followed up through its historical stages, but which critical investigations and the comparative study of literatures have established almost as a certainty.

In the ninth century a bold, venturesome traveller, Eldad ha-Dani,[23] a sort of Jewish Ulysses, appeared among Jews, and at the same time Judaism produced Sa'adia, its first great religious philosopher and Bible translator. The Church Fathers had always looked up to the rabbis as authorities; henceforth Jews were accepted by all scholars as the teachers of Bible exegesis. Sa'adia was the first of the rabbis to translate the Hebrew Scriptures into Arabic. Justly his work is said to "recognize the current of thought dominant in his time, and to express the newly-awakened desire for the reconciliation of religious practice, as developed in the course of generations, with the source of religious inspiration." Besides, he was the first to elaborate a system of religious philosophy according to a rigid plan, and in a strictly scientific spirit.[24] Knowing Greek speculations, he controverts them as vigorously as the Kalâm of Islam philosophy. His teachings form a system of practical ethics, luminous reflections, and sound maxims. Among his contemporaries was Isaac Israeli, a physician at Kairwan, whose works, in their Latin translation by the monk Constantine, attained great reputation, and were later plagiarized by medical writers. His treatise on fever was esteemed of high worth, a translation of it being studied as a text-book for centuries, and his dietetic writings remained authoritative for five hundred years. In general, the medical science of the Arabs is under great obligations to him. Reverence for Jewish medical ability was so exaggerated in those days that Galen was identified with the Jewish sage Gamaliel. The error was fostered in the Sefer Asaf, a curious medical fragment of uncertain authorship and origin, by its rehearsal of an old Midrash, which traces the origin of medicine to Shem, son of Noah, who received it from angels, and transmitted it to the ancient Chaldeans, they in turn passing it on to the Egyptians, Greeks, and Arabs.

Though the birth of medicine is not likely to have taken place among Jews, it is indisputable that physicians of the Jewish race are largely to be credited with the development of medical science at every period. At the time we speak of, Jews in Egypt, northern Africa, Italy, Spain, France, and Germany were physicians in ordinary to caliphs, emperors, and popes, and everywhere they are represented among medical writers. The position occupied in the Arabian world by Israeli, in the Occident was occupied by Sabattaï Donnolo, one of the Salerno school in its early obscure days, the author of a work on Materia medica, possibly the oldest original production on medicine in the Hebrew language.

The period of Jewish prosperity in Spain has been called a fairy vision of history. The culture developed under its genial influences pervaded the middle ages, and projected suggestions even into our modern era. One of the most renowned savants at the beginning of the period was the statesman Chasdaï ben Shaprut, whose translation of Dioscorides's "Plant Lore" served as the botanical textbook of mediæval Europe. The first poet was Solomon ibn Gabirol, the author of "The Source of Life," a systematic exposition of Neoplatonic philosophy, a book of most curious fortunes. Through the Latin translation, made with the help of an apostate Jew, and bearing the author's name in the mutilated form of Avencebrol, later changed into Avicebron, scholasticism became saturated with its philosophic ideas. The pious fathers of Christian philosophy, Albertus Magnus and Thomas Aquinas, took pains to refute them, while Duns Scotus and Giordano Bruno frequently consulted the work as an authority. In the struggle between the Scotists and the Thomists it had a prominent place as late as the fourteenth century, the contestants taking it to be the work of some great Christian philosopher standing on the threshold of the Occident and at the portals of philosophy. So it happened that the author came down through the centuries, recognized by none, forgotten by his own, until, in our time, behind the Moorish-Christian mask of Avencebrol, Solomon Munk discovered the Jewish thinker and poet Solomon ibn Gabirol.