Two centuries after Jesus' crucifixion and one century after the end of the macabre Jewish-Roman wars (that caused at least 2 million fatalities from both sides), the Roman Empire nearly collapsed during the Imperial Crisis (235-284 AD), under the combined pressures of invasions (Germanic raids in the north, Goths, Vandals, Alamanni from the Danube frontier, Sassanid attacks from the east), civil wars (numerous usurpers, the Empire split into competing states, Roman generals were fighting each other while neglecting their duties of defending the frontiers), the Plague of Cyprian (250-262, probably smallpox, 5,000 people a day were said to be dying in Rome) and economic depression (hyperinflation, agricultural crisis, barbaric migrations, disruption of Rome's internal trade network).
At the same time, Christianism, with its redemptive oratory and promises of afterlife salvation, was strengthening its numbers of followers massively. Due to this generally ominous situation, the Classical studies were under constant and reevaluation by the remaining scholars of the ancient world.
In these twilight years of the Classical antiquity, Neoplatonism was born in Alexandria by Ammonius Saccas and developed greatly by his student, Plotinus (ca 205-270 AD). Plotinus reinterpreted Platonism and Pythagoreanism in a monistic and pantheistic way, offering to the world a renewed, complete teaching that was harmonized and combined with the rest of the Greek philosophy, the Greco-Roman cultural traditions, Zoroastrianism, Egyptian theology, Eastern mysticism, and Hinduism.
According to Neoplatonism, the supreme cause of reality is "the One" (EN), which is both the creative source and the teleological end of all existing things. The second principle is the Mind (ΝΟΥΣ), which is corresponding to Plato's world of ideas and is a part of the One. The third and final principle is the Soul (ΨΥΧΗ), a part of which exists in every living being.
The purpose of human, according to Neoplatonists, is his individual part of the Soul to return to the primary source, the One. This can only be achieved, however, through virtuous life (ΚΑΘΑΡΣΙΣ).
Neoplatonism was the last great spark of the ancient philosophy. It became widely accepted in Alexandria, Pergamos, Athens, Antiocheia and Rome. The last Neoplatonic faculty was the Academy of Athens, which was closed arbitrary by Justinian in 529, and its scholars migrated to the Sassanid Persia. However, the Neoplatonic teachings never vanished from the eastern Roman Empire. Some of the most notable Neoplatonists were Iamblichus, Porfyrios, emperor Julian, Hypatia, Damaskios, Syrianos, Proklos, Asclepiodotos, Gemistos Plethon, Meister Eckhart and Marsilio Ficino.
