Plotinus is a philosopher of Late Antiquity. He is the founder of the philosophical current named 'Neoplatonism'. He was born in Egypt in 204/205 AD and studied philosophy in Alexandria. He founded a school in Rome where he taught until his death in 270 AD. We possess the totality of his writings, which were edited by Porphyry, his disciple and biographer, under the title 'Enneads'.
In his philosophical work Plotinus tries to prove the truth of Plato's philosophy by refuting Aristotle's critique of it. This leads Plotinus to the conception of an original philosophical system that proposes solutions to some of the essential problems of platonism which had thenceforth remained unresolved. Plotinus' system is strictly monistic. It is grounded upon the hierarchy of three primary principles, the One, Intellect and Soul, which are linked by a necessary chain causality. The One is the unstoppable and unlimited activity from which the whole of reality, intelligible as well as sensible, is generated. It is absolutely simple and, hence, unutterable. Intellect represents the archetype of the sensible world, on the one hand, the totality of intelligible beings as well as the intellectual activity that knows them, on the other. Soul is a dual entity: by its nature it belongs to the intelligible realm, but its function consists in the informing and holding together of the sensible world. The human individual, to the extent that it coincides with soul, may attain contemplation of the intelligible reality and, thence, self-knowledge.
The influence of Plotinus was important: it can be traced both in the philosophy of Late Antiquity and of the Middle Ages, and also in the philosophy of early Modernity and German Idealism.