Civilizations Flourish Fast Then Degenerate

Three times in the West a civilization has flourished—Greece in the 5th-6th century BC, Rome from the late Republic, and the Renaissance—each arising rapidly with a great efflorescence of science, art, and philosophy, then degenerating over time into something more rule-bound, rigid, hubristic, and certain it knows things, often after overstretching itself through empire; our own civilization is now at a point ready to collapse.