Sepher HaMispar [treatise on Algebra]

Rabbi Elijah Mizrachi (c.1450-1526), a native of Constantinople, was a member of the old Romaniot community that preceded the influx of exiles from Spain. In 1498 he became the foremost rabbinical authority not only in Constantinople but effectively throughout the entire Ottoman Empire. He has achieved literary fame due to his Responsa, but perhaps even more so thanks to his supercommentary on Rashi, known simply as “Mizrachi” (Venice, 1527). It was Mizrachi's third son, Israel, who published both the supercommentary and the present mathematical treatise. Though today few recall Mizrachi's mathematical ability, in its day Sepher HaMispar was highly regarded and even translated into Latin. See EJ, Vol. XII, cols. 182-4