Unlike the Jews, the Persians, or the civilization of India, Greek thinkers of the second-wave era generated no lasting religious tradition of world historical importance. The religion of these city-states brought together the unpredictable, quarreling, and lustful gods of Mount Olympus, secret fertility cults, oracles predicting the future, and the ecstatic worship of Dionysus, the god of wine. The distinctive feature of the classical Greek cultural tradition was the willingness of many Greek intellectuals to abandon this mythological framework, to affirm that the world was a physical reality governed by natural laws, and to assert that human rationality could both understand these laws and work out a system of moral and ethical life as well. In separating science and philosophy from conventional religion, the Greeks developed a way of thinking that bore some similarity to the secularism of Confucian thought in China.

Precisely why Greek thought evolved in this direction is hard to say. Perhaps the diversity and incoherence of Greek religious mythology presented its intellectuals with a challenge to bring some order to their understanding of the world. Greece’s geographic position on the margins of the great civilizations of Mesopotamia, Egypt, and Persia certainly provided intellectual stimulation. Furthermore, the growing role of law in the political life of Athens possibly suggested that a similar regularity also underlay the natural order.