The last of these ethical responses to Plato and Aristotle was the movement known as the Skeptics. Pyrrho of Elea, a contemporary of Zeo and Epicurus (ca. 365-275 B.C.) was the first leader of the Skeptics. He sought imperturbable tranquility, but not in the dogmatic theories of his day. Rather, he found happiness in absolute agnosticism and suspension of judgment.

Since we cannot know whether our sense perceptions agree with reality, we can never get beyond our senses. And so when our thoughts and our senses conflict, we have no criteria for distinguishing the true from the false. The result: when we suspend all judgment, tranquility will follow. We cannot grasp God or the eternals, and so we should give up our attempts to know them. And peace will come.

A second group of Skeptics descended from some of Plato's students at the Academy. Following Socrates' motto, "I know only that I do not know," they decided that we do not know even that we do not know. We know nothing, and we're sure of it.

Skepticism leads eventually to Eclecticism, a philosophy which combines truths from various sources without seeking a unified system of absolute knowledge. And nothing is more popular today than that.