This book provides the first edition and translation of an unpublished work by Elijah Del Medigo (1455c.-1493c.), which survives in both Latin and Hebrew versions. At the request of his Italian humanist patron Giovanni Pico della Mirandola, Del Medigo translated several works by Averroes from Hebrew into Latin, and wrote questions and commentaries concerning difficult aspects of Averroes’ philosophy.

The commentary on De substantia orbis constitutes one of Del Medigo’s most significant achievements, being based on an original work by Averroes which deals with the nature and the properties of the heavens according to the principles of Aristotelian cosmology. Del Medigo composed the Latin version of his commentary in 1485, but decided to translate it into Hebrew soon after.

A critical edition of both extant versions of this commentary will deepen our understanding of the reception of Averroes in the Renaissance, shedding new light on a neglected chapter of philosophical and scientific thought. Focusing on the representation of the cosmos and its relationship to human beings, this text will be of interest to scholars working not only on medieval and Renaissance philosophy, but also on the history of cosmology, astrology and science, intellectual history and the reception of Islamic thought in pre-modern intellectual circles.