If the world is an aggregate of relatively independent regions, then any assumption of universal laws is false and a demand for universal norms tyrannical: only brute force (or seductive deception) can then bend the different moralities so that they fit the prescriptions of a single ethical system. And indeed, the idea of universal laws of nature and society arose in connection with a life-and-death battle: the battle that gave Zeus the power over the Titans and all other gods and thus turned his laws into the laws of the universe.
