What is the science of metaphysics? The Arabic philosopher Averroes discusses the question of metaphysics’ scope, its aims, and its role in detail. His complex and coherent answer, presented in his Long Commentary on the Metaphysics and other works, accounts for metaphysics as the science of being, of God, of substance, and of causes. Among Latin Christian thinkers, different aspects of Averroes’ conception of metaphysics were discussed at length, adopted or rejected, interpreted and modified. This study explores Averroes’ theory, his Arabic predecessors, and his extensive reception in Latin commentaries on Aristotle’s Metaphysics between the 13th and early 16th century.