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Crescas, Ḥasdai


CRESCAS, ASDAI (c. 13401410/11), Spanish rabbi, philosopher, natural scientist; author of the anti-Aristotelian Hebrew classic, Or Adonai (The Light of the Lord). Son of a distinguished family of scholars and merchants, Crescas was raised in Barcelona, studying there under the renowned Talmudist and homilist Nissim ben Re'uven. He served as rabbi in Barcelona and from 1387 was an adviser to the king and queen of Aragon, Joan I and Violant. In 1389, Crescas assumed the post of rabbi of Saragossa, and the next year he was recognized by the throne as judge of all the Jews of Aragon. Following the anti-Jewish mob riots of 1391, in which thousands of Spanish Jewsincluding his only sonwere murdered and more than a hundred thousand were converted to Christianity, he devoted himself to the physical and spiritual reconstruction of the Jewish communities of Aragon and of Spain as a whole. His Epistle to the Jewish Community of Avignon (translated from the Hebrew in Kobler, 1952), dated 20 Heshvan 5152 (October 19, 1391), is a terse chronicle of the massacres that may have been written as background for entreaties to the papal court. The Epistle bears somber biblical allusions: the great Jewish communities of Spain are desolated Jerusalems (allusions are made to Lamentations 2:2, 2:4, 2:7, 5:4); Crescas's son is an Isaac sacrificed upon the altar (allusions are made to Genesis 22:2, 22:78). His Refutation of the Dogmas of the Christians (13971398), written in Catalan but surviving only in the Hebrew translation of Yosef ibn Shem ov (Biul ʿiqqarei ha-Notsrim, 1451; Frankfurt, 1860; Kearny, N.J., 1904; translated in Lasker, 1992), was intended to combat christianizing literature aimed at Jews and conversos. It is a nonrhetorical logical critique of ten basic elements of Christianity: original sin, salvation, the Trinity, the incarnation, the virgin birth, transubstantiation, baptism, the messiahship of Jesus, the New Testament, and demons. Even his profound philosophical treatise, The Light of the Lord (1410; Ferrara, 1555; Vienna, 18591860; Johannesburg, 1861; and Jerusalem, 1990, ed. S. Fisher), written in Hebrew, was to some extent a response to the troubles of his times. Its assault on Aristotelianism was in part motivated by the belief that Aristotelian philosophy was weakening the commitment of Jewish intellectuals to Judaism and thus facilitating their apostasy. Crescas is also the author of a philosophic homily on the Passover, which inquires into the epistemological status of faith based on miracles, such as the splitting of the Red Sea (Jerusalem, 1988).

The Light of the Lord, a counterblast to Maimonides' Guide of the Perplexed, was planned as the philosophical first part of a two-part work. The unwritten second part was to have been an analytic codification of rabbinic law and was intended to supersede Maimonides' rabbinic masterwork, the Mishneh Torah (Code of Law). The Light is divided into four books. Book 1 discusses three roots (shorashim ) of the Torah: God's existence, his unity, and his incorporeality. (In grouping these three principles together, Crescas followed Maimonides; cf., e.g., Guide of the Perplexed, intro. to part 2.) Book 2 discusses six fundaments (pinnot ) of the Torah: God's knowledge, providence, and power; prophecy; human choice; and the purposefulness of the Torah. The fundaments are concepts that follow necessarily (i.e., analytically) from Crescas's definition of the Torah as "the product of a voluntary action from the Commander, Who is the initiator of the action, to the commanded, who is the receiver of the action" (Light 2, intro.). Book 3 discusses eleven nonfundamental obligatory beliefs of the Torah: God's creation of the world, the immortality of the soul, reward and punishment, resurrection of the dead, the eternality of the Torah, the uniqueness of Moses' prophecy, the efficacy of the Urim and Tummim, the coming of the messiah, the efficacy of prayer, the spiritual value of repentance, and the special providential nature of the High Holy Days and the festivals. Book 4 examines thirteen nonobligatory beliefs held by sundry groups of Jews; for example, the Jewish Aristotelian proposition that God is the Intellect and the qabbalistic doctrine of metempsychosis (gilgul).

The Light is best known for its revolutionary logico-conceptual critique of Aristotelian physics (e.g., theories of space, time, motion, the vacuum, infinity), important parts of which were translated into Latin in Gianfrancesco Pico della Mirandola's Examen vanitatis doctrinae gentium (1520). In place of Aristotle's closed world, Crescas suggested that both space and time are infinite extensions in actu in which many worldsan infinite number?are continuously being created by the infinitely good, infinitely loving God. Crescas rejected Maimonides' Aristotelian proofs of God, but did offer a short metaphysical proof of his own: whether causes and effects are finite or infinite, there must be a cause of the whole of them; for if all are effects, they would have merely possible (i.e., contingent) existence, and thus they must have something that determines their existence over their nonexistence, and this is the first cause or God (Light 1.3.2, quoted in Spinoza, Epistle 12). Such rationalistic reflection, Crescas held, can incline one toward belief in the true God of religion, but only revelation can establish that belief firmly. In a celebrated discussion of human choice (Light 2.5), Crescas upheld the determinist view that the notion of human choice coheres with both divine omniscience and strict physical causality. In his theologically significant discussion of teleology (Light 2.6), he argued that love is the purpose of man, the Torah, the created universe, and God. Against the Aristotelians, he maintained that love is not intellectual, that the immortal essence of the human soul is not intellect, and that God is to be understood not as passionless Intellect but as joyfully loving.

Crescas's own highly original philosophy emerges out of his radical critique of Aristotle and of Aristotelians such as Maimonides, Ibn Rushd (Averroës), and Levi ben Gershom (Gersonides) and is argued in their vocabulary. In some areas, it is significantly influenced by Ibn Sīnā. Its spirit, however, recalls Abū āmid al-Ghazālī, Yehudah ha-Levi, and Nissim ben Re'uven. It is also colored by Qabbalah. Its precise relationship to Latin and Catalan writers is a subject for speculation.

Among Crescas's students was the well-known philosophical popularizer Yosef Albo, who in his Hebrew Sefer ha-'iqqarim (Book of Roots; 1425) adapted and simplified some of his master's teachings. Crescas's Light of the Lord had an appreciable influence on later Jewish philosophers, notably Judah Abravanel (c. 14601521) and Barukh Spinoza (16321677).

See Also

Jewish Thought and Philosophy, article on Premodern Philosophy.


For Crescas's life, see Yitzhak Baer's A History of the Jews in Christian Spain, 2 vols. (Philadelphia, 19611966). Crescas's critique of Aristotelian physics is the subject of Harry A. Wolfson's monumental Crescas' Critique of Aristotle (Cambridge, Mass., 1929); the volume includes Hebrew texts from the Light with facing English translation. Shlomo Pines explored the connection between Crescas's science and that of Nicole d'Oresme and other Latin authors in "Scholasticism after Thomas Aquinas and the Teachings of Hasdai Crescas and His Predecessors," Proceedings of the Israel Academy of Sciences and Humanities 1 (1967), n. p. See also Warren Zev Harvey's Physics and Metaphysiscs in asdai Crescas (Amsterdam, 1998). Crescas' philosophic homily is edited and analyzed in Aviezer Ravitzky, Dershat Ha-Pesa le-Rabbi asdai Crescas (Jerusalem, 1988). On Crescas's critique of Christianity, see Daniel J. Lasker's The Refutation of the Christian Principles by asdai Crescas (Albany, N.Y., 1992) and his Jewish Philosophical Polemics against Christianity in the Middle Ages (New York, 1977). On his influence on Spinoza, see Wolfson's The Philosophy of Spinoza, 2 vols. (Cambridge, Mass., 1934). Crescas's Epistle to the Jewish Community of Avignon is found in English translation in Franz Kobler's Letters of Jews through the Ages (London, 1952), pp. 272275.

Warren Zev Harvey (1987 and 2005)

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