Plotinus was born in Roman Egypt around 204/205 CE. His later followers treated him as the key founder of Neoplatonism, a later form of Platonism focused on a hierarchy of reality culminating in a first principle beyond ordinary being and thought.
In his late twenties, Plotinus went to Alexandria and studied with the Platonist teacher Ammonius Saccas. This period helped shape Plotinus’ approach of interpreting Plato through a unified, strongly metaphysical framework.
In 243 CE, Plotinus joined Emperor Gordian III’s campaign against Persia, reportedly seeking contact with Persian and Indian philosophical traditions. The campaign failed after Gordian’s death, and Plotinus eventually made his way to Rome, where his school would form.
After returning from the failed expedition, Plotinus settled in Rome and began teaching. His seminars became a center for philosophical debate, and they provided the social setting where his metaphysical system was refined through discussion.
Beginning in the 250s, Plotinus wrote a series of short treatises responding to problems raised in teaching and debate. These texts develop the core metaphysical structure of Neoplatonism—especially the One (the highest principle), Intellect (Nous), and Soul—and the idea that all things “flow” from the One while the soul can return through contemplation and virtue.
Plotinus died in 270 CE. His students preserved his writings, which were not originally arranged as a single book, making later editing and organization crucial for how his system would be read and taught.
Plotinus’ student Porphyry edited the treatises and arranged them into six groups of nine, the Enneads. This editorial step helped turn Plotinus’ seminar-style writings into a teachable canon and stabilized the metaphysical system for later Neoplatonists.
In the early 4th century, Iamblichus became a leading Neoplatonist and a founder of the Syrian branch of the tradition. He strongly emphasized theurgy (ritual practices aimed at divine union), shifting Neoplatonism toward a more explicitly religious metaphysics and influencing later systematic thinkers.
In the 5th century, Proclus became head (diadochos, or successor) of the Platonic school in Athens. He systematized Neoplatonic metaphysics into a highly structured framework and helped make Athenian Neoplatonism a major late antique intellectual force.
Around 520 CE, Damascius became the final leader in the succession of Platonic scholars at Athens. His work reflects a late-stage Neoplatonic concern with the limits of human language and thought when speaking about the first principle.
In 529 CE, Emperor Justinian closed the Athenian philosophical school along with other pagan schools, restricting non-orthodox teaching. This marked a major institutional break for the Athenian Neoplatonic tradition, even though Neoplatonic ideas continued elsewhere.
After the 529 closure, Damascius and several colleagues left for the Persian court of Khosrow I. Their departure shows how Neoplatonism’s metaphysical schools were being displaced from their older public settings within the Eastern Roman Empire.
A peace agreement in 533 CE between Justinian and Khosrow I included terms allowing the displaced philosophers to return. By this stage, however, the classical Athenian institutional base for pagan Neoplatonism had effectively ended, closing the period (c. 204–529) in which Plotinus’ metaphysical system grew into a school tradition.
Plotinus and Neoplatonism's metaphysical system (c. 204–529 CE)