 It is well known that this central component of the Vienna Circle’s arsenal, the analytic/synthetic distinction, came under sharp criticism from Quine in his “Two Dogmas of Empiricism” (1951a), less so that the criticism can only be sustained by relying on objections of a type first published by Tarski. The argument is more complex, but here is a very rough sketch. So as to discard the analytic/synthetic distinction as an unwarranted dogma, Quine in “Two Dogmas” argued for the in-principle revisability of all knowledge claims and criticised the impossibility of defining analyticity in a non-circular fashion. The first argument tells against the apodictic a priori of old (the eternal conceptual verities), but, as we shall see, it is unclear whether it tells against at least some of the notions of the a priori held in the Vienna Circle. The second argument presupposes a commitment to extensionalism that likewise can be argued not to have been shared by all in the Circle. By contrast, Tarski had merely observed that, at a still more fundamental level, he knew of no basis for a sharp distinction between logical and non-logical terms. (For relevant primary source materials see also Quine 1935, 1951b, 1963, Carnap 1950, 1955, 1963b, their correspondence and related previously unpublished lectures and writings in Creath 1990, the memoir Quine 1991, and Tarski 1936.)