Presocratic philosophers develop rational cosmologies and explain the origin of the cosmos without appealing to traditional mythology. Concepts related to good and evil emerge from this context; more precisely, by the time of Heraclitus there has emerged a conception of cosmic goodness which allows one to infer what evil would be for human beings situated in such a cosmos. The earliest Presocratic philosophers lived in the Greek colony of Miletus in the sixth century bce. Earlier Presocratics provide a conception of cosmic order but do not discuss the normative implications of such order for human beings. Even the fragments of Xenophanes, who also flourished at the end of the sixth or early fifth century bce, do not provide enough support for a conception of evil. Presocratic philosophers after Parmenides introduce new cosmologies to explain the existence of ordered world-systems.