P.F. Strawson 
Scepticism and Naturalism [PDF ebook] 
Some Varieties

First published in 1987. By the time of his death in 2006, Sir Peter Strawson was regarded as one of the world»s most distinguished philosophers. Unavailable for many years, Scepticism and Naturalism is a profound reflection on two classic philosophical problems by a philosopher at the pinnacle of his career. Based on his acclaimed Woodbridge lectures delivered at Columbia University in 1983, Strawson begins with a discussion of scepticism, which he defines as questioning the adequacy of our grounds for holding various beliefs. He then draws deftly on Hume and Wittgenstein to argue that we must distinguish between »hard», scientific naturalism; or »soft», humanistic naturalism. In the remaining chapters the author takes up several issues in which sceptical doubts play an important role, in particular the nature of transcendental arguments and including the objectivity of moral philosophy, the mental and the physical, and the existence of abstract entities. Scepticism and Naturalism is essential reading for those seeking an introduction to the work of one of the twentieth century»s most important and original philosophers.