When I was a graduate student a slogan was proposed for a department T-shirt: “Philosophy. We've done less in 2,500 years than most people do in a single day.” The slogan was rejected. But it reflects a serious sceptical sentiment. When we consider the remarkable progress made by science in the past 400 years, philosophy appears in an unfavourable light. At a minimum, we would like to know why there is so little agreement among professional academics regarding the solutions to philosophical problems, their proper articulation, and even the methods suitable to resolving them.

My desire to find a satisfactory explanation of pervasive disagreement has sustained my interest in the ancient Sceptics. From their arguments and strategies, we can construct various explanations for why philosophers have not and perhaps will not reach consensus. There are, of course, plenty of non-sceptical solutions as well, and I am not convinced that I have a satisfactory explanation yet. But reflecting on the arguments of the ancient Sceptics has proved to be immensely valuable in getting to grips with the broad issue of the limits of reason.

The Sceptics also have some fascinating things to say about the proper response to our rational limitations. These responses are meant to show how Scepticism is a viable position and not merely a set of arguments confined to the study or the classroom.