 Syrianus (in antiquity known as “the Great”) was a teacher of philosophy and, if we can trust the evidence, of rhetoric in Athens during the late 4th and early 5th centuries CE. He was a slightly younger contemporary of Augustine of Hippo (354–430). Born in Alexandria in the second half of the 4th century, he received his basic education there but later went on to study philosophy under Plutarch of Athens (c. 350–431/2), who had revived Plato’s Academy. When Plutarch died in 431/2, Syrianus succeeded him as head of the Athenian school. During this last stage in his life, Syrianus became the teacher of the young Proclus (410/2–485), who in turn succeeded him as scholarch, either immediately or not long after Syrianus’ death in 437. The particular circumstances of Syrianus’ life are almost entirely unknown, and of his copious philosophical work only the important commentaries on books Beta (III), Gamma (IV), and Mu and Nu (XIII–XIV) of Aristotle’s Metaphysics survive.