ISRAELI, ISAAC BEN SOLOMON

born 832/855, Egypt died 932/955, Al-Qayrawan, Tunisia Arabic Abu Ya-'qub Ishaq Ibn Sulayman Al-isra'ili, also called Isaac Israeli, or Isaac The Elder Jewish physician and philosopher, widely reputed in the European Middle Ages for his scientific writings and regarded as the father of medieval Jewish Neoplatonism. Although there is considerable disagreement about his birth and death dates, he is known to have lived more than 100 years and never to have married or to have had children. Israeli first gained note as an oculist, maintaining a practice near Cairo until about 904, when he became court physician in Al-Qayrawan to the last Aghlabid prince, Ziyadat Allah. He also studied medicine there under Ishaq ibn 'Amran al-Baghdadi, with whom he sometimes has been confused. Some five years after his arrival, Israeli entered into the service of al-Mahdi, the founder of the North African Fatimid dynasty (9091171), whose capital was Al-Qayrawan. At the request of the caliph, Israeli wrote eight medical works in Arabic. All were translated into Latin in 1087 by the monk Constantine, who claimed to have written them himself. Not until 1515 was their true authorship uncovered, and the works were republished in Lyon under the title Omnia Isaac Opera (All of Isaac's Works); the editor, however, mistakenly included the writings of other medical scholars as well. Israeli's scientific works include standard treatises on fevers, urine, pharmacology, ophthalmology, and ailments and treatments. He wrote also on logic and psychology, showing particular insight in the field of perception. Of his philosophical writings, Kitab al-hudud (Hebrew: Sefer ha-gevulim, The Book of Definitions) is best known. Beginning with a discussion of Aristotle's four types of inquiry, Israeli goes on to present 56 definitions, including definitions of wisdom, intellect, soul, nature, reason, love, locomotion, and time. Others of his philosophical works include Sefer ha-ru'ah ve-ha-nefesh (Treatise on Spirit and Soul), probably part of a larger exegetical effort, and Kitab al-jawahir (Book of Substances). Israeli's thought was influenced heavily by two major sources: the great 9th-century Islamic philosopher al-Kindi and a lost pseudo-Aristotelian treatise on such matters as the source of being, the nature of the intellect, and the course of the soul. Israeli's interpretation of eschatological matters in the light of Neoplatonic mysticism was to influence Solomon ibn Gabriol in the 10th century and other later Jewish philosophers.