Lehrer on a premise of epistemic cogency

Abstract

In "Against Simplicity", Keith Lehrer objects to any attempt to justify common sense beliefs by appeal to their explanatory simplicity) The focus of this particular criticism is Bertrand Russell's well-known response to skepticism in The Problems of Philosophy. But clearly Lehrer has a larger target in mind, Lehrer suggests that a number of philosophers have employed the pattern of reasoning typified by Russell, a pattern of reasoning he argues is fallacious. Amongst these Lehrer cites Wilfrid Sellars, Paul Ziff, Gilbert Harman, and even Lehrer himself in earlier days. 2 All of these authors, like Russell, have suggested that common sense beliefs can be justified because they provide the simplest explanation of other things we befieve. Russell, for example, argued that common sense beliefs such as "There really is a cat before me" can be justified in the face of skeptical challenges by appeal to their simplicity. The common sense explanation that my sense-data are caused by a real cat is simpler than any skeptical alternative such as the hypothesis that I am only hallucinating a cat, or that I am being presented with cat-like sense data by an evil demon. Lehrer argues that any appeal to simplicity along the lines employed by Russell is fallacious. "Explanation, however simple, cannot yield justification in these matters. ''3 In this paper I will argue that an appeal to explanatory simplicity such as that employed by Russell need not be fallacious. Indeed the proponents of explanatory simplicity can avoid Lehrer's objection in precisely the same way Lehrer avoids it himself with respect to his own brand of coherentism. Lehrer construes Russell as defending the following argument: . The belief that I see a cat, an external object, is simpler than