(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 c. 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?–c. 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.