Externalism and Twin Earth

Abstract

The dialectical situation, for my purposes, begins with externalist arguments, mainly by Tyler Burge, that purport to show that internalism is untenable. The arguments of central concern are those that begin with Twin-Earth-style thought experiments.¹ Anyone reading this has probably already heard of the Twin Earth thought experiments, and probably knows something about the arguments that the thought experiments have inspired. I will not try to produce here a comprehensive presentation and analysis of the literature that has grownup around the thought experiments. I will, however, say enough to make apparent the style of argument the thought experiments have inspired, and to convey the force of those arguments. Though I intend for this book to be approachable by those not already familiar with the literature, minimal familiarity with that literature is probably a prerequisite even for being interested in what I will have to say. At any rate, such familiarity will not hurt, and certainly is recommended, as the papers by Putnam and Burge on which the literature is founded are among the best examples of contemporary analytic philosophy.