Abstract

It is widely accepted that Russell wrongly took Wittgenstein to be concerned with the conditions required for an ideal language in his _Tractatus Logico-Philosophicus_. Given Russell’s relatively extensive communications with Wittgenstein, this misunderstanding is puzzling. I argue that Russell’s mistake rests on two prior assumptions for which he had some justification. First, communications with Wittgenstein were plausibly interpreted by Russell as confirming, rather than refuting, the belief that Wittgenstein shared with him the view that psychology, epistemology, and logic are interdependent. Second, results from these areas in turn led Russell to the view that ordinary language is irredeemably vague and, as such, in need of replacement with an ideal language. In truth, however, Wittgenstein severed psychology and epistemology from his work and saw vagueness as a surface phenomenon only.