The work De Causis, attributed to David, a forgotten Jewish philosopher, must be classed with Gabirol's "Source of Life," on account of its Neoplatonism and its paramount influence upon scholasticism. In fact, only by means of a searching analysis of these two works can insight be gained into the development and aberrations of the dogmatic system of mediæval philosophy.
Other sciences, too, especially mathematics, flourished among them. One century after he wrote them, the works of Abraham ibn Ezra, renowned as an astronomer and mathematician, were translated into Latin by Italians, among whom his prestige was so great that, as may still be seen, he was painted among the expounders of mathematical science in an Italian church fresco representing the seven liberal arts. Under the name Abraham Judæus, later corrupted into Avenare, he is met with throughout the middle ages. Abraham ben Chiya, another distinguished scientist, known by the name Savasorda, compiled the first systematic outline of astronomy, and in his geographical treatise, he explained the sphericity of the earth, while the Latin translation of his geometry, based on Arabic sources, proves him to have made considerable additions to the stock of knowledge in this branch. Moses Maimuni's intellectual vigor, and his influence upon the schoolmen through his medical, and more particularly his religio-philosophical works, are too well known to need more than passing mention.
Even in southern France and in Germany, whither the light of culture did not spread so rapidly as in Spain, Jews participated in the development of the sciences. Solomon ben Isaac, called Rashi, the great exegete, was looked up to as an authority by others beside his brethren in faith. Nicolas de Lyra, one of the most distinguished Christian Bible exegetes, confesses that his simple explanations of Scriptural passages are derived pre-eminently from Rashi's Bible commentary, and among scientific men it is acknowledged that precisely in the matter of exegesis this French monk exercised decisive influence upon Martin Luther. So it happens that in places Luther's Bible translation reveals Rashi seen through Nicolas de Lyra's spectacles.
In the quickened intellectual life of Provence Jews also took active part. David Kimchi has come to be regarded as the teacher par excellence of Hebrew grammar and lexicography, and Judah ibn Tibbon, one of the most notable of translators, in his testament addressed to his son made a complete presentation of contemporary science, a cyclopædia of the Arabic and the Hebrew language and literature, grammar, poetry, botany, zoology, natural history, and particularly religious philosophy, the studies of the Bible and the Talmud.
The golden age of letters was followed by a less creative period, a significant turning-point in the history of Judaism as of spiritual progress in general. The contest between tradition and philosophy affected every mind. Literature was widely cultivated; each of its departments found devotees. The European languages were studied, and connections established between the literatures of the nations. Hardly a spiritual current runs through the middle ages without, in some way, affecting Jewish culture. It is the irony of history that puts among the forty proscribers of the Talmud assembled at Paris in the thirteenth century the Dominican Albertus Magnus, who, in his successful efforts to divert scholastic philosophy into new channels, depended entirely upon the writings and translations of the very Jews he was helping to persecute. Schoolmen were too little conversant with Greek to read Aristotle in the original, and so had to content themselves with accepting the Judæo-Arabic construction put upon the Greek sage's teachings.
Besides acting as intermediaries, Jews made original contributions to scholastic philosophy. For instance, Maimonides, the first to reconcile Aristotle's teachings with biblical theology, was the originator of the method adopted by schoolmen in the case of Aristotelian principles at variance with their dogmas. Frederick II., the liberal emperor, employed Jewish scholars and translators at his court; among them Jacob ben Abba-Mari ben Anatoli, to whom an annuity was paid for translating Aristotelian works. Michael Scotus, the imperial astrologer, was his intimate friend. His contemporaries were chiefly popular philosophers or mystics, excepting only the prominent Provençal Jacob ben Machir, or Profatius Judæus, as he was called, a member of the Tibbon family of translators. His observations on the inclination of the earth's axis were used later by Copernicus as the basis of further investigations. He was a famous teacher at the Montpellier academy, which reminds me to mention that Jews were prominently identified with the founding and the success of the medical schools at Montpellier and Salerno, they, indeed, being almost the only physicians in all parts of the known world. Salerno, in turn, suggests Italy, where at that period translations were made from Latin into Hebrew. Hillel ben Samuel, for instance, the same who carried on a lively philosophic correspondence with another distinguished Jew, Maestro Isaac Gayo, the pope's physician, translated some of Thomas Aquinas's writings, Bruno di Lungoburgo's book on surgery, and various other works, from Latin into Hebrew.
These successors of the great intellects of the golden age of neo-Hebraic literature, thoroughly conversant with Arabic literature, busied themselves with rendering accessible to literary Europe the treasury of Indian and Greek fables. Their translations and compilations have peculiar value in the history of literary development. During the middle ages, when the memory of ancient literature had perished, they were the means of preserving the romances, fairy tales, and fables that have descended, by way of Spain and Arabia, from classical antiquity and the many-hued Oriental world to our modern literatures. Between the eleventh and the thirteenth century, the foundations were laid for our narrative literature, demonstrating the importance of delight in fable lore, stories of travel, and all sorts of narratives, for to it we owe the creation of new and the transformation of old, literary forms.
In Germany at that time, a Jewish minnesinger and strolling minstrel, Süsskind von Trimberg, went up and down the land, from castle to castle, with the poets' guild; while Santob di Carrion, a Jewish troubadour, ventured to impart counsel and moral lessons to the Castilian king Don Pedro before his assembled people. A century later, another Jew, Samson Pnie, of Strasburg, lent his assistance to the two German poets at work upon the continuation of Parzival. The historians of German literature have not laid sufficient stress upon the share of the Jews, heavily oppressed and persecuted though they were, in the creation of national epics and romances of chivalry from the thirteenth to the fifteenth century. German Jews, being more than is generally recognized diligent readers of the poets, were well acquainted with the drift of mediæval poetry, and to this familiarity a new department of Jewish literature owed its rise and development. It is said that a Hebrew version of the Arthurian cycle was made as early as the thirteenth century, and at the end of the period we run across epic poems on Bible characters, composed in the Nibelungen metre, in imitation of old German legend lore and national poetry.
If German Jews found heart for literary interests, it may be assumed as a matter of course that Spanish and Provençal Jews participated in the advancement of their respective national literatures and in Troubadour poetry. In these countries, too, the new taste for popular literature, especially in the form of fables, was made to serve moral ends. A Jew, Berachya ben Natronaï, was the precursor of Marie de France, the famous French fabulist, and La Fontaine and Lessing are indebted to him for some of their material. As in the case of Aristotelian philosophy and of Greek and Arabic medical science, Jews assumed the rôle of mediators in the transmission of fables. Indian fables reached their Arabic guise either directly or by way of Persian and Greek; thence they passed into Hebrew and Latin translations, and through these last forms became the property of the European languages. For instance, the Hebrew translation of the old Sanskrit fox fables was the one of greatest service in literary evolution. The translator of the fox fables is credited also with the translation of the romance of "The Seven Wise Masters," under the title Mishlé Sandabar. These two works gave the impetus to a great series in Occidental literature, and it seems altogether probable that Europe's first acquaintance with them dates from their Hebrew translation.
In Arabic poetry, too, many a Jew deservedly attained to celebrity. Abraham ibn Sahl won such renown that the Arabs, notorious for parsimony, gave ten gold pieces for one of his songs. Other poets have come down to us by name, and Joseph Ezobi, whom Reuchlin calls Judæorum poeta dulcissimus, went so far as to extol Arabic beyond Hebrew poetry. He was the first to pronounce the dictum famous in Buffon's repetition: "The style is the man himself." Provence, the land of song, produced Kalonymos ben Kalonymos (Maestro Calo), known to his brethren in faith not only as a poet, but also as a scholar, whose Hebrew translations from the Arabic are of most important works on philosophy, medicine, and mathematics. As Anatoli had worked under Emperor Frederick II., so Kalonymos was attached to Robert of Naples, patron of Jewish scholars. At the same time with the Spanish and the German minstrel, there flourished in Rome Immanuel ben Solomon, the friend of Dante, upon whose death he wrote an Italian sonnet, and whose Divina Commedia inspired a part of his poetical works also describing a visit to paradise and hell.