Plotinus (A.D. 204–70), Greco-Roman Neoplatonist philosopher. Born in Egypt, though doubtless of Greek ancestry, he studied Platonic philosophy in Alexandria with Ammonius Saccas (232–43); then, after a brief adventure on the staff of the Emperor Gordian III on an unsuccessful expedition against the Persians, he came to Rome in 244 and continued teaching philosophy there until his death. He enjoyed the support of many prominent people, including even the Emperor Gallienus and his wife. His chief pupils were Amelius and Porphyry, the latter of whom collected and edited his philosophical essays, the Enneads (so called because arranged by Porphyry in six groups of nine). The first three groups concern the physical world and our relation to it, the fourth concerns Soul, the fifth Intelligence, and the sixth the One. Porphyry’s arrangement is generally followed today, though a chronological sequence of tractates, which he also provides in his introductory Life of Plotinus, is perhaps preferable. The most important treatises are I.1; I.2; I.6; II.4; II.8; III.2–3; III.6; III.7; IV.3–4; V.1; V.3; VI.4–5; VI.7; VI.8; VI.9; and the group III.8, V.8, V.5, and II.9 (a single treatise, split up by Porphyry, that is a wide-ranging account of Plotinus’s philosophical position, culminating in an attack on gnosticism).
Plotinus saw himself as a faithful exponent of Plato (see especially Enneads V.1), but he is far more than that. Platonism had developed considerably in the five centuries that separate Plato from Plotinus, taking on much from both Aristotelianism and Stoicism, and Plotinus is the heir to this process. He also adds much himself. See also EMANATIONISM , NEOPLATONISM. J.M.D.