or Isaac the Elder
born 832/855, Egypt
died 932/955, Al-Qayrawān, Tun.
Egyptian Jewish physician and philosopher.
He began his medical career as an oculist in Cairo and later became court physician to al-Mahdī, founder of the Fātimid dynasty in northern Africa. He wrote several medical treatises in Arabic that were later translated into Latin and circulated in Europe. Schooled in Classical learning, he wrote philosophical works, including his Book of Definitions , which discusses Aristotle's four types of inquiry and then provides definitions of wisdom, intellect, soul, nature, love, and time. His interpretation of eschatological matters in light of Neoplatonic mysticism was very influential for later Jewish philosophers.