Isaac (Abū Ibrāhīm) ben Joseph ibn Barūn was a philologist and linguist from Saragossa. The dates of his birth and death are not known, nor are any details of his life, except that he was a disciple of the poet and grammarian Levi ibn al-Tabbān. Ibn Barūn’s magnum opus was his Kitābal-Muwāzana bayn al-Lugha al-ʿIbrāniyya wa ʾl-ʿArabiyya (Book of Comparison between the Hebrew and Arabic Languages). Written after 1128 and not preserved in its entirety, it is an outstanding work of comparative Semitics, building upon the contributions of Ibn Quraysh, Ibn Janāḥ, and other earlier compara…