The Spanish-Jewish preacher and philosopher Joseph Albo was the last major figure of the philosophical surge in medieval Jewry. Little is known about his early life; he was probably born at Monreal, in the kingdom of Aragon, and he asserted that Hasdai Crescas was his teacher. Albo was one of the principal apologists for the Jews at the Colloquium of Tortosa (February 7, 1413–November 3, 1414); his activities as apologist and preacher are reflected in the style of his philosophic classic, Sefer ha-'Ikkarim (The Book of Roots).

Albo's acknowledged and unacknowledged borrowings from other writers are so extensive that he was accused of plagiarism in his own age, as well as in more recent and more sensitive times. We must recognize, however, that Albo's purpose was to systematize and thus to defend the dogmas of Judaism rather than to produce an original philosophic...