first translated from Arabic into Latin in the early thirteenth century, the philosophical works of Averroes were initially respected as valuable aids to understanding the true philosophy of Aristotle. William of Auvergne, Bishop of Paris and author of a philosophically astute theological synthesis of Greek and Arabic thought with Christian doctrine, openly expressed his appreciation with praise for Averroes. But by the mid-thirteenth century many of Averroes’ teachings were under attack with his conceptions of human nature and separate immaterial intellect the subject of sharply focussed and heated argumentative assaults by Aquinas, Albert and others.2 Their arguments were not primarily theological but rather philosophical criticisms which charged that Averroes, [End Page 507] particularly in his Psychology, failed to understand Aristotle and misrepresented Aristotle’s thought in his confused exposition of Aristotle’s Psychology. This is so well-known to us in our own day that Averroes’ name has even made its way into Copi’s elementary logic text as part of an exercise using a quotation from Duns Scotus in which this Islamic philosopher is called “That accursed Averroes.” Scotus remarks that
… [A]ll philosophers commonly assign “rational” as the difference that properly defines man, meaning by “rational” that the intellective soul is an essential part of man.
In fact, to put it briefly, no philosopher of any note can be found to deny this except that accursed Averroes (ille maledictus Averroes) in his commentary on De anima, Bk III, where his fantastic conception, intelligible neither to himself nor to others, assumes the intellective part of man to be a sort of separate substance united to man through the medium of sense images.3
In a general way Averroes’ name has been associated with naturalistic thought labeled “Latin Averroism” which appeared to deny the personal immortality of the soul, to follow Aristotle regarding the eternity of the world, and to place the rational in priority to the religious. Not at all surprisingly, such an under-standing of Averroes’ thought sees him as a personification not only of religious unorthodoxy well deserving of suppression and correction in the cultural contexts of Medieval Christianity and Islam, but also of philosophical foolishness and of heresy against the Aristotelian tradition.4
Such a view of the work of Averroes, however, is in part a consequence of a failure to appreciate fully the depth of reflection which Averroes brought to Aristotelian texts and philosophical principles. His account of the relationship of philosophical Psychology and metaphysics and of how Psychology provides key principles both for the establishment of the science of Metaphysics and for the explanation of separate intellect. That account provides evidence of a sophisticated mind at work weaving from Aristotelian threads a coherent cloth of metaphysical teachings. And what provides the basis for this account is [End Page 508] nothing other than his controversial and seldom understood doctrine of the separate Material Intellect which is one for all humankind. The present article concerns that teaching on separate intellect and aims to show how Averroes can assert in his Long Commentary on the De Anima and in his Long Commentary on the Metaphysics that principles for the science of Metaphysics are established in the science of Psychology, a science which is itself a branch of Natural Philosophy or Physics.
At the beginning of chapter 1 of book VI of his Metaphysics, Aristotle states that, “We are seeking the principles and the causes of the things that are, and obviously of things qua being.”5 Setting forth a division of the sciences into practical, productive and theoretical, he explains that while the theoretical science of mathematics deals with its objects as immovable and as separable from matter, “natural science deals with things which are inseparable from matter but are not immovable.” But “first science deals with things which are both separable and immovable.” He goes on to assert the existence of three theoretical sciences, namely mathematics, natural science and theology, and to assert the existence of a highest science dealing with the highest genus. This is First Philosophy, which is universal in scope. But this First Philosophy will be the theoretical science of theology only if its subject matter, separate...