How Hard Are the Sceptical Paradoxes?

The sceptic about the external world presents us with a paradox: an apparently acceptable argument for an apparently unacceptable conclusion—that we do not know anything about the external world. Some paradoxes, for instance the liar and the sorites, are very hard. The defense of a purported solution to either of these two inevitably deploys the latest in high-tech philosophical weaponry. On the other hand, some paradoxes are not at all hard, and may be resolved without much fuss. They do not contain profound lessons about the human condition. Where should we place the sceptical paradoxes? Rather strikingly, there is no consensus on the matter. Everyone agrees that the liar and the sorites are deeply challenging, even—or perhaps especially—those who claim to have solved them. Many philosophers think that (at least some) sceptical paradoxes are up there with the liar and sorites. Some of these philosophers are optimists—they think that there is a way out, short of embracing scepticism. Some are pessimists, who see little hope. But they are all united in the conviction that one or another sceptical paradox is fearfully difficult. On the other side, there are many who are decidedly underimpressed. To them, sceptical paradoxes do not ‘‘signal genuine collisions between features of our thinking which go deep’’—the sceptic is just another guy with a bad argument. This paper argues for the second ‘‘ho-hum’’ reaction. Two sceptical paradoxes are considered in some detail (sections 3 and 4): the first formulated with particular clarity by Ayer (1956, ch. 2); the second the centerpiece of the classic pessimist manifesto The Significance of Philosophical Scepticism (Stroud 1984a). It is argued—admittedly with the benefit of a century of hindsight—that each has a premise that is only superficially plausible. As far as I know, there is really only one other candidate for a sceptical paradox that is worth taking seriously. As it happens, I find it completely unparadoxical;