Abstract

In contrast to the recent trend of taking external world skepticism as a narrow problem for a demanding conception of "objective" or "certain" knowledge about the world, my thesis offers a re-examination of the distinctively perceptual basis of the skeptical problem. On my view the skeptic challenges the very possibility of rationally justifying beliefs in so far as they are based on sense experience, a characterization that helps to explain the continuity into the modern period of the ancient skeptical challenge to the pretensions of reason. What is newly radical in external world skepticism is the discovery of the inner realm of the mind, and hence, of inner states as a component of every sense experience. ;I argue that the skeptic relies upon a distinctive, intuitively compelling, conception of sense experience which I call the causal model of experience. This is the view that experience is constituted by self-standing subjective experiences and their external causes, where cause and effect are logically distinct existences. The causal model is not to be identified with a view of perception as epistemically mediated by a "veil of ideas", though it can lead one to embrace that doctrine. My aim is twofold: to understand the motivation for the skeptic's causal model of experience; and to show that, when thought through, this model can ultimately be shown to be incoherent. ;The causal model has its roots in 17th century scientific metaphysics and the idea that the world can be exhaustively explained in terms of mechanical interactions between primary-qualified corpuscles governed by mathematically describable laws. I argue that the perceptual relation is not a mere efficient causal relation and I show that the skeptic is in the incoherent position of wanting a "private" language to describe his subjective experiences despite insisting on conditions of autonomy that deprive his terms of the normativity that is a necessary condition of meaning. Thus I do not answer the skeptical problem so much as undercut the basis upon which it is posed in the first place