This is a course about the history of Skepticism from the ancient Greeks to today, with special attention to the political ramifications of questioning man's ability to know the world and himself with any certainty. We will discuss the debates raging between Plato and the Sophists, the rise of Christianity in the Roman world, and the so-called 'Skeptical Crisis' of the Renaissance as well as Pierre Bayle's Skepticism and David Hume's. In addition the Natural Law tradition will be explored and the relationship between Skepticism and Conservatism. In the second part, we will explore the systematic relations between Skepticism and politics. What is skeptical doubt? When is doubt relevant? How does Skepticism relate to tolerance and to freedom of expression? And can it help us to solve political problems not only in a critical, but also in a creative way?