ABSTRACT
As best I can determine, the idea of spectrum inversion made its first appearance in the philosophical literature when John Locke, in the Essay, entertained the possibility that "the same Object should produce in several Men's Minds different Ideas at the same time; v.g. the Idea , that a Violet produces in one Man’s Mind by his Eyes, were the same that a Marigold produced in another Man’s, and vice versa."1 It was obviously part of Locke’s supposition that the color experiences of the two people differ in such a way that the difference could not manifest itself in their be havior and their use of color words, and we will take this as an es sential feature of full-fledged intersubjective spectrum inversion. This “ inverted spectrum hypothesis” was revived in the early years of this century, and in the heyday of logical positivism it was a fa vorite target for applications of the verificationist theory of mean ing; there are classic formulations and discussions of it in the writ ings of C. I. Lewis, Moritz Schlick, Hans Reichenbach, John Wisdom, Max Black, and J . J . C. Smart,2 and it lurks beneath the surface, and sometimes at it, in many of Wittgenstein’s discussions of “private experience.”
