In its essentials, the schema of creation and emanation propounded by Isaac Israeli and his Neoplatonic source (or sources) was taken over by Solomon ibn Gabirol, a celebrated 11th-century Hebrew liturgical poet who was also the earliest Jewish philosopher of Spain. His chief philosophical work, written in Arabic but preserved in full only in a 12th-century Latin translation titled Fons vitae (“Fountain of Life”), makes no reference to Judaism or to specifically Jewish doctrines and is a dialogue between a disciple and a master who teaches him true philosophical knowledge. Despite its prolixity and many contradictions, it is an impressive work. Few medieval texts so effectively communicate the Neoplatonic conception of the existence of a number of planes of being that differ according to their ontological priority, the derivative and inferior ones constituting a reflection in a grosser mode of existence of those that are prior and superior.

One of Ibn Gabirol’s central concerns was the divine will, which appears to be both part of and separate from the divine essence. Infinite according to its essence, the will is finite in its action. It is described as pervading everything that exists and as being the intermediary between the divine essence and matter and form. Will was one of the traditional terms used by medieval theologians to identify the entity intermediate between the transcendent Deity and the world or the aspect of the Deity involved in creation. According to a statement in Fons vitae, matter derives from the divine essence, whereas form derives from the divine will. This suggests that the difference between matter and form has some counterpart in the Godhead and also that universal matter is superior to universal form. Some of Ibn Gabirol’s statements seem to support the superiority of universal matter; other passages, however, appear to imply the superiority of universal form.

Form and matter, whether universal or particular, exist only in conjunction. All things, with the sole exception of God, are constituted through the union of the two, the intellect no less than corporeal substance. In fact, the intellect is the first being in which universal matter and form are conjoined. The intellect contains and encompasses all things. It is through the grasp of the various planes of being, through ascending in knowledge to the world of the intellect and apprehending what is above it—the divine will and the world of the Deity—that humans may “escape death” and reach “the source of life.”

Judah ha-Levi

Judah ben Samuel ha-Levi (c. 1075–1141), another celebrated Hebrew poet from Spain, was the first medieval Jewish thinker to base his thought consciously and consistently on arguments drawn from Jewish history. His views are set forth in an Arabic dialogue, al-Hazari (Hebrew Sefer ha-Kuzari), the full title of which is translated as “The Book of Proof and Argument in Defense of the Despised Faith.” This work is usually called Kuzari—i.e., “the Khazar.”

Basing his narrative on the historical conversion to Judaism of the Khazars (c. 740), a Turkic-speaking people in central Eurasia, ha-Levi relates that their king, a pious man who did not belong to any of the great monotheistic religions, dreamed of an angel who said to him, “Your intentions are pleasing to the Creator, but your works are not.” To find the correct way to please God, the king sought guidance from a philosopher, from a Christian, from a Muslim, and finally—after hesitating to invite a representative of a people degraded by historical misfortune—from a Jewish scholar, who then converted him to Judaism. The angel’s words in the king’s dream may be regarded as a kind of revelation. Ha-Levi used this element of the story to suggest that it is not the spontaneous activity of reason that impels human beings to undertake the quest for the true religion but the gift of prophecy—or at least a touch of the prophetic faculty (or a knowledge of the revelations of the past).

The argument of the philosopher whose advice is sought by the king confirms this point. This disquisition is a brilliant piece of writing that lays bare the essential differences between the Aristotelian God, who is wholly indifferent to human individuals, and the God of the Jewish religion. The God of the philosophers, who is pure intellect, is not concerned with the works of human beings; moreover, the cultural activities to which the angel clearly refers—activities that involve both mind and body—cannot, from a philosophical point of view, either help or hinder humans in the pursuit of the philosophers’ supreme goal, the attainment of union with the active intellect, a “light” of the divine nature. This union was supposed to confer knowledge of all intelligible things on the individual; the supreme goal, therefore, was purely intellectual in nature.

In opposition to the philosopher’s faith, the religion of the Jewish scholar in the Kuzari is based on the fact that God may have a close, direct relationship with humans, who are not conceived primarily as beings endowed with intellect. The postulate that God can have intercourse with a creature made of the disgusting materials that compose the human body is scandalous to the king and prevents his acceptance of the doctrine concerning prophecy, expounded by the Muslim sage (just as the extraordinary nature of the Christological dogmas deters him from adopting Christianity).

The Jewish scholar argues that it is contemplation not of the cosmos but of Jewish history that procures knowledge of God. Ha-Levi was aware of the odium attached to the doctrine of the superiority of one particular nation; he held, however, that this teaching alone explains God’s dealings with humanity, which, like many other things, reason is unable to grasp. The controversies of the philosophers serve as proof of the failure of human intelligence to find valid solutions to the most important problems.

Ha-Levi’s dialogue was also directed against the Karaites. He shows the necessity and celebrates the efficacy of a blind, unquestioning adhesion to tradition, which the Karaites rejected. Yet he expounds a theology of Jewish exile that seems to have been influenced by Karaite doctrine. According to ha-Levi, even in exile the course of Jewish history is not determined like that of other nations by natural causes, such as material strength or weakness; the decisive factor is whether the Jews are religiously observant or disobedient. The advent of Christianity and Islam, in his view, prepares other nations for conversion to Judaism, an event that will occur in the eschatological period at the end of history.

Other Jewish thinkers, c. 1050–c. 1150

Many other Jewish thinkers appeared in Spain during the period from the second half of the 11th century to the first half of the 12th. Bahya ben Joseph ibn Pakuda wrote one of the most popular books of Jewish spiritual literature, Kitāb al-hidāyah ilā farā’iḍ alqulūb (“Guidance to the Duties of the Heart”), which combines a theology influenced by Saʿadia with a moderate mysticism inspired by the teachings of the Sufis. The commandments of the heart—that is, those relating to thoughts and sentiments—are contrasted with the commandments of the limbs—that is, the Mosaic commandments enjoining or prohibiting certain actions. Bahya maintained that both sets of commandments should be observed (thus rejecting the antinomian position) but made clear that he was chiefly interested in the commandments of the heart.

Abraham bar Hiyya Savasorda, a mathematician, astrologer, and philosopher, outlined in Megillat ha-megalle (“Scroll of the Revealer”) a view of Jewish history that is reminiscent of ha-Levi but does not emphasize its uniqueness to the same degree; it is also set forth in much less impressive fashion. Living in Barcelona under Christian rule, Bar Hiyya wrote scientific and philosophical treatises not in Arabic but in Hebrew. Hebrew was also used by Abraham ibn Ezra (died 1167), a native of Spain who travelled extensively in Christian Europe. His commentaries on the Bible contributed to the diffusion among the Jews of Greek philosophical thought, to which Ibn Ezra made many disjointed references. His astrological doctrine had a great influence on some philosophers.

The last outstanding Jewish philosopher of the Islamic East, Abū al-Barakāt al-Baghdādī (who died as a very old man sometime after 1164), also belongs to this period. An inhabitant of Iraq, he was converted to Islam in his old age (for reasons of expediency, according to his biographers). His philosophy appears to have had a strong impact on Islamic thought, though its influence on Jewish philosophy and theology is very hard to pin down and may be practically nonexistent. His chief philosophical work, Kitāb al-muʿtabar (“The Book of That Which Has Been Established by Personal Reflection”), contains very few references to Jewish texts or topics. Abū al-Barakāt rejected Aristotelian physics completely. According to him, time is the measure of being and not, as Aristotle taught, the measure of motion; he also replaced Aristotle’s two-dimensional concept of place with the three-dimensional notion of space, the existence of which is independent of the existence of bodies.

Abraham ibn Daud

Abraham ibn Daud (12th century), who is regarded as the first Jewish Aristotelian of Spain, was primarily a disciple of Avicenna, the great 11th-century Islamic philosopher. He may have translated or helped to translate some of Avicenna’s works into Latin, according to one plausible hypothesis, for he lived under Christian rule in Toledo, a town that in the 12th century was a centre for translators. His historical treatises, written in Hebrew, manifest his desire to familiarize his fellow Jews with the historical tradition of the Latin world, which at that time was alien to most of them. But his philosophical work, Sefer ha-emuna ha-rama (“Book of Sublime Faith”), written in 1161 in Arabic, shows few if any signs of Christian influence.

The doctrine of emanation set forth in this work describes in the manner of Avicenna the procession of the 10 incorporeal intellects, the first of which derives from God. This intellect produces the second intellect, and so on. Ibn Daud questioned in a fairly explicit manner Avicenna’s views on the way the second intellect is produced; his discipleship did not mean total adherence. Ibn Daud’s psychology was also, and more distinctively, derived from Avicenna. The argumentation leading to a proof that the rational faculty is not corporeal attempts to derive the nature of the soul from the fact of immediate self-awareness. Like Avicenna, Ibn Daud founded psychology on a theory of consciousness.

Ibn Daud often referred to the accord that, in his view, existed between philosophy and religious tradition. As he remarked, the Sefer ha-emuna ha-rama was not for readers who, in their simplicity, are satisfied with what they know of religious tradition or for those who have a thorough knowledge of philosophy. It was intended for readers of one type only: those who, being acquainted with the religious tradition on the one hand and having some rudiments of philosophy on the other, are “perplexed.” It was for the same audience that Maimonides wrote his The Guide for the Perplexed.