VICTORINUS, GAIUS MARIUS (4th century A.D.), Roman grammarian, rhetorician and Neoplatonic philosopher, an African by birth, lived during the reign of Constantius II. He taught rhetoric at Rome (one of his pupils being Jerome) and in his old age became a convert to Christianity. His con version is said to have greatly influenced that of Augustine. When Julian published an edict forbidding Christians to lecture on polite literature, Victorinus closed his school. A statue was erected in his honour as a teacher in the Forum Trajanum.
The treatise De Definitionibus (ed. T. Stangl in Tuiliana et Mario-Victoriniana, Munich, 1888) is probably by him and not by Boetius, to whom it was formerly attributed. His manual of prosody, in four books, taken almost literally from the work of Aphthonius, is extant (H. Keil, Grammatici Latini, vi.). It is
doubtful whether he is the author of certain other extant treatises attributed to him which will be found in Keil. His commentary on Cicero's De Inventione (in Halm's Rhetores Latini Minores, 1863), is very diffuse, and is itself in need of commentary. His extant theological writings will be found in J. P. Migne, Curses Patrologiae Latinae, viii.
See G. Geiger, C. Marius Victorinus Afer, ein neuplatonischer Philosoph (Metten, 1888) ; G. Koffmann, De Mario Victorino phil osopho Christiano (Breslau, 188o) ; R. Schmid, Marius Victorinus Rhetor and seine Beziehungen zu Augustin (Kiel, 1895) ; Gore in Dictionary of Christian Biography, iv.; M. Schanz, Geschichte der romischen Litteratur, iv. 2 (1904) ; Teuffel, Hist. of Roman Literature (Eng. trans., 1900), 408.