3rd century
Rome cracks. Diocletian divides — and by dividing, kills its unity
What happened — and why
The Crisis of the Third Century (235–284)
Fifty years — twenty-six emperors, most of them murdered. Barbarians press in from every side. Plague. Hyperinflation. The collapse of trade networks.
The philosophical cause
Diocletian — The army chooses the emperors — which means power belongs to whoever commands the legions. The system cannot function.
Diocletian creates the Tetrarchy (293): four rulers. It saves the empire in the short term — and lays the mechanism for its division.
Plotinus founds Neoplatonism
Plotinus writes the Enneads — the last great system of ancient philosophy. The One, the Nous, the Soul — a hierarchy of reality without a Christian God.
The philosophical cause
Plotinus — When the political world collapses, philosophers turn inward. Plotinus sought what does not depend on Rome.
His pupil Porphyry edits the texts. Two hundred years later Augustine and Pseudo-Dionysius will translate Neoplatonism into the language of Christianity.
