A book on scepticism from Anthony Grayling is to be greatly valued. Grayling is rare among academic philosophers: he is not only a brilliant thinker, but also has the power to communicate serious ideas to a wide audience. The subject of Scepticism is one of particular interest to people today. It is well known that Grayling reserves particular scepticism for religious statements, but that is only part of this compelling new book. Scepticism as a philosophical term is as old as the Greeks but has more recently been advanced by Montaigne, Descartes and Hume. To these, what little we know that se