Hesiod's Works and Days is largely a work about agriculture, it opens with a bit of wisdom about two different kinds of strife, good and bad. Hesiod identified strife, not only as a negative, but also potentially as a positive, a way of inspiring people to try to be better than their neighbor, improving their lives in the process. The idea of this kind of good strife is found throughout the world, from the forces driving markets to be more efficient, to political strife, to the fascinating psychological effects of opponent processing.