Isaac Ben Solomon Israeli

From New World Encyclopedia

Isaac Israeli ben Solomon (in Hebrew Yitzhak ben Shlomo ha-Yisraeli; in Arabic Abu Yaqub Ishak ibn Suleiman al-Yisra'ili; also known as Isaac Israeli the Elder) (c. 832 -932, or 845-940) was an Egyptian-Jewish physician and philosopher. He was one of the earliest medieval Jewish philosophers to incorporate Greek philosophy into Jewish metaphysics. He was the first to synthesize the Neoplatonic idea of emanation with the traditional Jewish doctrine of creation ex nihilo by proposing that God, as a voluntary agent, created the first level of matter through His power and will, and that all lower levels of beings emanated from it. He was also the first Jewish philosopher to give a psychological explanation of prophecy.

He was renowned as a physician in the Arab world and served as court physician to the Fatimid caliph 'Ubaid Allah al-Mahdi. Several of his medical works were translated into Latin in 1087 by the Christian monk Constantine of Carthage and used as textbooks in Europe for several centuries. Their real authorship was obscured until their publication as Opera Omnia Isaac in Lyon, France, in 1515.


According to most of the Arabic authorities, Isaac Israeli ben Solomon was born in Egypt before 832 and died at Kairouan, Tunisia, in 932. Crescas Abraham ben Hasdai, quoting the biographer Sanah ibn Sa'id al-Kurtubi ("Orient, Lit." iv., col. 230), says that Isaac Israeli died in 942. Heinrich Grätz ("Gesch." v. 236), while stating that Isaac Israeli lived more than one hundred years, gives the dates 845-940; and Steinschneider ("Hebr. Uebers." pp. 388, 755) places his death in 950. Little is known about his antecedents or his personal life, except that he never married or had children.

Israeli wrote on philosophy, natural history, medicine, mathematics, astronomy, and other scientific topics; he was reputed to be one who knew all the "seven sciences." He first gained a reputation as a skillful oculist; after he went to Kairwan he studied general medicine under Ishak ibn Amran al-Baghdadi, with whom he is sometimes confounded ("Sefer ha-Yashar," p. 10a). Around 904 Israeli was appointed court physician to the last Aghlabid prince, Ziyadat Allah III. Five years later, when the Fatimid caliph Ubaid Allah al-Mahdi became master of northern Africa, of which Kairouan was the capital, Israeli entered his service. The caliph enjoyed Israeli’s company because of his wit and of the repartees with which he succeeded in confounding the Greek al-Hubaish. At the request of al-Mahdi, Israeli composed eight medical works in Arabic.

Thought and Works

Isaac Israeli ben Solomon was among the earliest medieval Jewish philosophers to incorporate Greek thought into Jewish metaphysics. Though he does not appear to have had a decisive impact on later Jewish thinkers, the ideas pioneered by Israeli were employed and developed by those who sought to establish a rational, philosophical basis for the Jewish faith. These ideas also found their way into the thought of Christian Scholastics.

Israeli was the first to synthesize the Neoplatonic idea of emanation with the traditional Jewish doctrine of creation ex nihilo. He proposed that God, as a voluntary agent, created a first level of substance, or matter, through His power and will, from which emanated all successive levels of the universe. This concept was vital to the cosmologies of later Jewish philosophers. Israeli elaborated a Neoplatonic explanation of the soul, teaching that it could ascend through all the levels of emanation to achieve ultimate communion with God. He was also the first Jewish philosopher to give a psychological explanation of prophecy.

Carmoly (Ẓiyyon, i. 46) concludes that the Isaac who was so violently attacked by Abraham ibn Ezra in the introduction to his commentary on the Pentateuch, and whom he calls in other places Isaac the Prattler, and Ha-Yizhak, was Isaac Israeli ben Solomon. Israeli received praise from other Biblical commentators, such as Jacob b. Ruben, a contemporary of Maimonides, and Hasdai ben Abraham Crescas.

A commentary on the Sefer Yezirah ascribed to Israeli has given rise to controversy among later scholars. Steinschneider (in his Al-Farabi, p. 248) and Carmoly (in Jost's Annalon, ii. 321) attribute the authorship to Israeli, because Abraham ibn Hasdai Crescas, and Jedaiah Bedersi, in his apologetical letter to Solomon ben Adret (Orient, Lit. xi. cols. 166-169), speak of a commentary by Israeli on the Sefer Yeẓirah. Some scholars, however, believe the words Sefer Yezirah simply denote the Book of Genesis. David Kaufmann (R. E. J. viii. 126), Sachs (Orient, Lit. l.c.), and especially Grätz (Gesch. v. 237, note 2) are inclined to attribute the authorship of this commentary to Israeli's pupil Dunash ibn Tamim.

Israeli produced a number of philosophical works and exegetic commentaries, including a commentary on Genesis and a Book of Definitions, which discusses Aristotle's "theory of four causes" and provides definitions of wisdom, intellect, soul, nature, love, and time. His lectures attracted a large number of pupils, among whom the two most prominent were Abu Ya'far ibn al-Yazzar, a Muslim, and Dunash ibn Tamim.


Israeli was known in Latin Europe primarily as a physician. At the request of caliph 'Ubaid Allah al-Mahdi, Israeli composed eight medical works in Arabic, which were considered by Muslim physicians as "more valuable than gems." The Christian monk Constantine of Carthage translated several of Israeli's medical treatises into Latin in 1087, and they were used as textbooks at the University of Salerno, the earliest university in Western Europe. Constantine of Carthage omitted the author’s name, and Israeli’s authorship was not discovered until they were published in 1515 in Lyon, France, France, as "Opera Omnia Isaci" (in that collection, works of other physicians were erroneously attributed to Israeli). Part of his medical works were also translated into Spanish.

Philosophical Works

  • "Kitab al-Hudud wal-Rusum," translated into Hebrew by Nissim b. Solomon (14th cent.) under the title "Sefer ha-Gebulim weha-Reshumim," a philosophical work of which a Latin translation is quoted in the beginning of the "Opera Omnia." This work and the "Kitab al-Isthihat" were severely, criticized by Maimonides in a letter to Samuel ibn Tibbon ("Iggerot ha-Rambam," p. 28, Leipsic, 1859), in which he declared that they had no value, inasmuch as Isaac Israeli ben Solomon was nothing more than a physician.
  • "Kitab Bustan al-Hikimah," on metaphysics.
  • "Kitab al-Hikmah," a treatise on philosophy.
  • "Kitab al-Madkhal fi al-Mantik," on logic. The last three works are mentioned by Ibn Abi Usaibi'a, but no Hebrew translations of them are known.
  • "Sefer ha-Ruah weha-Nefesh," a philosophical treatise, in a Hebrew translation, on the difference between the spirit and the soul, published by Steinschneider in "Ha-Karmel" (1871, pp. 400-405). The editor is of opinion that this little work is a fragment of a larger one.
  • A philosophical commentary on Genesis, in two books, one of which deals with Gen.I:20.

Medical works

  • "Kitab al-Hummayat," in Hebrew, "Sefer ha-hadhaot," a complete treatise, in five books, on the kinds of fever, according to the ancient physicians, especially Hippocrates.
  • "Kitab al-Adwiyah al-Mufradah wa'l-Aghdhiyah," a work in four sections on remedies and aliments. The first section, consisting of twenty chapters, was translated into Latin by Constantine under the title "Diætæ Universales," and into Hebrew by an anonymous translator under the title "Hib'e ha-Mezonot." The other three parts of the work are entitled in the Latin translation "Diætæ Particulares"; and it seems that a Hebrew translation, entitled "Sefer ha-Mis'adim" or "Sefer ha-Ma'akalim," was made from the Latin.
  • "Kitab al-Baul," or in Hebrew, "Sefer ha-Shetan," a treatise on urine, of which the author himself made an abridgment.

"Kitab al-Istihat," in Hebrew, "Sefer ha-Yesodot," a medical and philosophical work on the elements, which the author treats according to the ideas of Aristotle, Hippocrates, and Galen. The Hebrew translation was made by Abraham ben Hasdai at the request of the grammarian David Kimhi.

  • "Manhig ha-Rofe'im," or "Musar ha-Rofe'im," a treatise, in fifty paragraphs, for physicians, translated into Hebrew (the Arabic original is not extant), and into German by David Kaufmann under the title "Propädeutik für Aerzte" (Berliner's "Magazin," xi. 97-112).
  • "Kitab fi al-Tiryah," a work on antidotes. Some writers attribute to Isaac Israeli two other works which figure among Constantine's translations, namely, the "Liber Pantegni" and the "Viaticum," of which there are three Hebrew translations. But the former belongs to Mohammed al-Razi and the latter to 'Ali ibn 'Abbas or, according to other authorities, to Israeli's pupil Abu Jaf'ar ibn al-Jazzar.


  • Ibn Abi Usaibi'a, 'Uyun al-Anba', ii. 36, 37, Bulak, 1882;
  • 'Abd al-Laṭif, Relation de l'Egypte (translated by De Sacy), pp. 43, 44, Paris, 1810;
  • Hammer-Purgstall, Literaturgesch. der Araber, iv. 376 (attributing to Israeli the authorship of a treatise on the pulse);
  • Wüstenfeld, Gesch. der Arabischen Aerzte, p. 51;
  • Sprenger, Gesch. der Arzneikunde, ii. 270;
  • Leclerc, Histoire de la Médecine Arabe, i. 412;
  • Carmoly, in Revue Orientale, i. 350-352;
  • Grätz, Gesch.3d ed., v. 257;
  • Haji Khalfa. ii. 51, v. 41, et passim;
  • Steinschneider, Cat. Bodl. cols. 1113-1124;
  • idem, Hebr. Bibl. viii. 98. xii. 58;
  • Dukes, in Orient, Lit. x. 657;
  • Gross, in Monatsschrift, xxviii. 326;
  • Jost's Annalen, i. 408.

ISBN links support NWE through referral fees

  • Altmann, A., and S. M. Stern. Isaac Israeli: A Neoplatonic philosopher of the early tenth century: his works translated with comments and an outline of his philosophy. (Scripta Judaica), Oxford University Press, 1958.
  • Honderich, Ted (ed.). The Oxford Companion to Philosophy New Edition. Oxford University Press, USA; 2 edition, 2005.
  • Richards, Ruth M. Text and concordance of Isaac Israeli's Tratado de las fiebres. (Spanish series), Hispanic Seminary of Medieval Studies, 1982.

External links

All links retrieved March 6, 2018.

General Philosophy Sources


New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

The history of this article since it was imported to New World Encyclopedia:

Note: Some restrictions may apply to use of individual images which are separately licensed.

This article incorporates text from the 1901–1906 Jewish Encyclopedia, a publication now in the public domain.