The philosophy of the Greco-Roman world from the sixth century BC to the sixth century AD laid the foundations for all subsequent Western philosophy.
Its greatest figures are Socrates (fifth century BC) and Plato and Aristotle (fourth century BC).
The enormously diverse range of further important thinkers who populated the period includes
Ancient philosophy was principally pagan, and was finally eclipsed by Christianity in the sixth century AD, but it was so comprehensively annexed by its conqueror that it came, through Christianity, to dominate medieval and Renaissance philosophy. This eventual symbiosis between ancient philosophy and Christianity may reflect the fact that philosophical creeds in late antiquity fulfilled much the same role as religious movements, with which they shared many of their aims and practices (from Routledge Encyclopedia of Philosophy).