Asad (or: Usayda) al-Yahūdī (“the Jew”) was a prominent physician in Mamluk Egypt and Syria during the second half of the thirteenth century and the first half of the fourteenth. The only contemporaneous historian to mention Asad was his associate Khalīl ibn Aybak al-Ṣafadī (1297–1363), who included entries on him in his biographical dictionaries.

As an erudite physician, Asad was knowledgeable in the rational sciences, especially metaphysics and physics. He worked as a general physician and ophthalmologist but was most famous as a gifted surgeon w…