Plotinus, 205-270, Neoplatonist philosopher. A native of Egypt, perhaps of Roman descent, he went to Alexandria c.232 to devote himself to philosophy. For 10 years he was a dedicated disciple of Ammonius Saccas. To study the philosophies of India and Persia, Plotinus in 242 traveled in the Eastern expedition of Gordian III, the Roman emperor. From 244 he lived in Rome, where his school attracted wide attention. Many followed his advice and example; they gave their wealth to those in need and turned to contemplative thought. However, Plotinus never taught or practiced extreme asceticism. His pupil Porphyry wrote a biography of him and was responsible for the arrangement of his works, which were written after 253, into six Enneads, or groups of nine treatises.

The theories of Plotinus were fundamentally those of Plato but included elements of other Greek philosophies as well, all drawn together into an original system that rapidly won followers and in time had considerable influence on the thinkers of the Christian Church, although Plotinus himself opposed Christianity. His development of the idea of emanation was fuller than that found in the teachings of the Stoics and of Philo. This cosmological conception is the chief point of Neoplatonism, which received its form from Plotinus. All else, even his ethics, depends upon this view of the world.

Among the virtues set forth by Plotinus are political or social virtues, concerning a human being's relations to others; the higher purifying virtues, needed to help the soul become like God by removing from it as much as possible that which is of the senses; and the still higher deifying or enlightening virtures, through the exercise of which a human being may attain to the fulfillment of his or her true nature. But unification with the highest, with God, is not possible through thought. It is attained only when the soul, in an ecstatic state, loses the restraint of the body and has for a time an immediate knowledge of God (see mysticism).

(born AD 205, Lyco, or Lycopolis, Egypt?—died 270, Campania) Egyptian-Roman philosopher. At age 27 he traveled to Alexandria, where he studied philosophy for 11 years. In about 242 he joined the expedition of the Roman emperor Gordian III against Persia in order to learn about the philosophies of the Persians and Indians. He went to Antioch and then to Rome, where he settled at age 40, becoming the centre of an influential circle of intellectuals. His attempt to form a Platonic republic in Campania circa 265 was halted by the emperor Gallienus. He was the founder of the school of philosophy known as Neoplatonism; his collected works, the Enneads (from Greek, enneas: “set of nine”), arranged by his disciple Porphyry (232?–circa 305), are the first and greatest collection of Neoplatonic writings. For Plotinus, philosophy was not only a matter of abstract speculation but also a way of life and a religion. His works strongly influenced early Christian theology, and his philosophy was widely studied and emulated for many centuries.

Learn more about Plotinus with a free trial on Britannica.com.