The Ban on Science and Its Effects
The ban by Solomon ben Abraham ben Adret on teaching science and philosophy to Jewish students under twenty-five did more harm to science than to philosophy, and its effect was more visible in Spain than in France. Maimonides' influence was still strong among the Jews who managed to continue living in southern France. Joseph Caspi dared to write treatises on logic and ethics to guide his son, and defended the tradition of philosophical freedom whose highest example Maimonides had given in his Guide for the Perplexed. This way of thinking prepared the ground for a great Jewish thinker, Levi ben Gershon.
Levi ben Gershon, Gersonides
Known in Christendom as Gersonides, he earned his living by medicine, like most Jewish philosophers, and in fact embodied Hippocrates' wish for complete men who are both physician and philosopher. Born at Bagnols in 1288 into a family of scholars, he spent nearly all his life at Orange, Perpignan and Avignon, and was able to pursue his studies in peace under the protection of the popes. No branch of science escaped his study and no philosophical question escaped his inquiring eye. Gersonides was an expert Talmudist who also advanced the mathematics of music and wrote poetry. In the mathematics and astronomy of his age he was a star of the first magnitude, and before Maurolico (1575) and Pascal (1654) he worked out by mathematical reasoning the method of counting the permutations of n objects (1321).
His treatise on trigonometry opened the way for the researches of Regiomontanus and drew such wide attention that Pope Clement VI commissioned its translation into Latin, under the title On Sines, Chords and Arcs (1342). He invented or perfected the instrument called "Jacob's staff" to measure the altitude of stars accurately, and for two centuries it remained a useful navigator's tool. Gersonides spent long years observing the heavens and then, with great skill, raised objections to the Ptolemaic system. He discussed and doubted the sun-centered hypothesis, rejecting it in a tone that suggests it had a few followers even then. He also improved the camera obscura and used it together with Jacob's staff to measure precisely the changes in the apparent diameter of the sun and moon.
The Wars of the Lord
As his science was shaped by Arab mathematics and astronomy, so his philosophy rested on the commentaries Averroes wrote to introduce Aristotle's works. Between 1319 and 1321 Levi wrote new commentaries on these commentaries and reviewed everything Aristotle had treated in his treatises: logic, physics, astronomy, meteorology, botany, zoology, psychology and metaphysics, quoting Maimonides in very many places. His philosophical views and the greater part of his scientific discoveries are gathered in a work in Hebrew, The Wars of the Lord (1317-1329). In medieval Jewish philosophy only the Guide for the Perplexed exceeds it in importance and authority. Following Maimonides, it tries to combine Greek thought with Jewish faith, though it makes the scale of faith much lighter.
When we observe that Averroes and Thomas Aquinas made the same attempt, the first to reconcile Islam with Aristotle and the second Christianity, we see how the dominance of Aristotle's philosophy over medieval theology led to the disintegration and collapse of religious belief and turned the "age of faith" into the "age of reason." To soothe his religious opponents Gersonides declared that if his ideas were shown to contradict the words of scripture he was ready to reject them at once, one of the tricks of most scholastic philosophers. With this preface he discussed in detail God, creation, the eternity of the world and the immortality of the soul, and as his conclusions contradicted scripture he interpreted its words so boldly and combatively that his critics changed his book's title and called it "The Wars Against the Lord."
Gersonides says that we should not take stories such as "the sun standing still for Joshua" literally, but should understand that such "miracles" were probably natural events whose causes were forgotten or unknown to men. And at last he declares his adherence to open rationalism: "The Torah cannot prevent us from accepting what our reason judges to be true." Levi ben Gershon drew his proof of God's existence from what the atheist Holbach later called "the system of nature," and held that the law and order of the world manifest the "intellect" that governs the universe. Like theologians, he argues that in nature everything seems made as a means serving an end, and that the Lord has given every creature the means to preserve itself, grow and reproduce. The world, as universe or total order, was created in time but not out of nothing. A mass of motionless, formless matter has existed from eternity, and creation gave it form and life.
Between God and created forms stands an intermediate power that Gersonides, following Aristotle and Averroes, calls the "active intellect," a radiation of God's mind that guides all creatures. Man becomes a soul, and as far as the soul depends on individual appetites it is mortal; at the stage where it can grasp universal concepts and understand the order and unity of the universe, it becomes a conscious part of the "active intellect," an eternal substance.
Hasdai Crescas: Faith over Reason
Gersonides' philosophy was rejected by the Jews, who regarded it as essentially derived from Averroes or a kind of rationalist method whose final result was the destruction of religious faith. Christian thinkers read his works, and Spinoza was strongly influenced by his ideas, but the spirit of thoughtful Jews was reflected more truly and faithfully in the works of Hasdai ben Abraham Crescas, who adopted the conservative method of Solomon ben Adret.
Hasdai Crescas was born at Barcelona in 1340 and lived through the peak of anti-Semitism. He was arrested on the charge of desecrating the host and released shortly after, and his son, on the very night he was to marry, died a martyr in the massacre of the Jews (1391). Persecution made Hasdai's faith firmer, since only belief in a just God and a rewarding heaven could make bearable the horror of a life so full of suffering and empty of justice. Seven years after his son's death Crescas published a treatise in Spanish, trying to explain to Christians why a Jew should not be expected to become Christian. With great modesty and tolerance he showed that the dogmatic principles of the Christians, such as the fall, the Trinity, the virgin birth, the incarnation, the atonement and transubstantiation, produce the greatest contradictions and hardest rational impossibilities.
Yet when he came to write his major work, The Light of the Lord (1410), he took a stand from which Christians could defend these views: he abandoned reason and brought it to its knees before faith. Though not officially a rabbi, he agreed with them that the repeated disasters that fell on the Jewish people were a punishment from the Lord for their sin of wanting to mix and pollute the religion revealed to Moses with rational arguments. If he himself wrote a book on philosophy, it was not because he thought it valuable and sound, but to expose the weakness and inadequacy of philosophy and reason and prove the truth of faith. He rejected the efforts of Maimonides and Gersonides to reconcile Judaism with Aristotle and protested: "Who is this Greek with whom God must agree?" He opposed the Aristotelian view that the highest divine attribute is knowledge, and held that it is love; God is absolute goodness.
Crescas admitted that reason cannot reconcile two contradictory ideas, divine foreknowledge and human freedom. So we must not deny freedom, but must set reason aside. For the peace of our souls and our moral health we must believe in God, in human freedom and in the survival of the soul, and need not try to prove these beliefs by rational arguments. We must choose between our vain and weak reason, which shakes faith and breeds despair, and the humble faith and divine word that alone console us in the face of the injustices and humiliations of life.
Albo and the Long Silence
Crescas was the last of the brilliant line of Jewish philosophers of the Middle Ages, but in his lifetime he was not admired or honored by his people. It was his pupil Joseph Albo who drew the notice of philosophical minds and won fame with his more attractive book, the Ikkarim ("Principles," given in the book under a different title). It combined the ideas of Maimonides and Crescas in an eclectic method, and its result was more in harmony with orthodox Judaism, which does not at all accept the irrationality of faith. After Albo's death (1444) the Jews almost lost their insight into philosophy and history until the coming of Spinoza.
Massacres, disorder, poverty and the lack of homes and jobs had broken the spirit of the Jews and reduced their number to a minimum not seen since the fall of Jerusalem in AD 70. The most outcast and despised of human groups took refuge in sorrowful religious hymns, sought comfort in the synagogues, and spent their lives in hope of divine forgiveness, vindication on earth and eternal happiness. Jewish scholars buried themselves in the pages of the Talmud and limited their thinking to interpreting the law of Moses, while others sank so deep into mysticism, to find the divine secrets, that they saw the stages of their misery as a ladder for climbing to heaven. Jewish poetry fell from lyric heights, and only a weak form of it now and then rose against the revolution of the times or softened life's mockeries with its humor.
The Jewish people did not rouse from this long and also healing sleep until that humble Jew of Amsterdam stood up and, by mixing Judaism, scholastic philosophy and Descartes's method of reasoning, created a magnificent compound of religion and science. With the appearance of a figure like Spinoza the Jews were able once again to regain their place in the world arena of human thought, which lies beyond the bounds of race and time.