 It remained open for Carnap then to declare his notion of analyticity to be only operationally defined for constructed languages and to let that notion be judged entirely in terms of its utility for meta-theoretical reflection. Just on that account, however, a last hurdle remains: finding a suitable criterion of significance for theoretical terms that allows the distinction between analytic and synthetic statements to be drawn in the non-observational, theoretical languages of science. (This was a problem ever since the non-eliminative reducibility of disposition terms had been accepted and one that still held for Carnap’s 1956 criterion; see section 3.5 below). Only if that can be done, we must therefore add, can Carnap claim his formalist explicationist project to emerge unscathed from the criticisms of both Tarski and Quine.