and of the necessity of accounting for the cause of this uniformity. The Gnostic sects, which were of philosophical origin, simply show the definite acceptance of this First Cause and, having accepted it as on a plane far removed above imperfection and variation, suggest intermediary emanations as explaining the production of an imperfect and variable universe from a primary source which is itself perfect and unchanging. The descriptive accounts of the successive emanations, each less perfect than that from which it proceeds, which ultimately produced the world in which we perceive phenomena, are different in different Gnostic systems, often crude enough and grotesque in our eyes, and frequently drawing from Christianity or Judaism or some other of the oriental religions which were then attracting the attention of the Roman world. But these details are of minor importance. All Gnostic theories bear witness to the belief that there is a First Cause, absolutely real, perfect, eternal, and far removed above this world of time and space, and that some emanation or emanations must have intervened to connect the resultant world, such as we know it, with this sublime Cause: and such belief indicates in crude form a general conviction which was getting hold of all current thought in the early centuries of the Christian era.
Complementary to this was the psychological teaching represented by the Aristotelian commentator Alexander of Aphrodisias who taught at Athens, A.D. 198-211. His extant works include commentaries