Who, exactly, wrote down the foundational texts of the Oral Torah? Who is responsible for the compiling of the Talmud? These were some of the questions addressed to Sherira Gaon, the Rosh Yeshiva of the great city of Pumbedita in Babylon in 987 by a young Rabbi in Tunisia. His famous response, preserved for over a thousand years, is an impressive survey of the Jewish intellectual tradition, leading up to the establishment of the greatest Talmudic centers in Jewish history.