So we are back to the problem of analyticity. It seems that analyticity cannot be established without synonymy, which itself is unsupportable. Thus one is tempted to suppose in general that the truth of a statement is analyzable into a linguistic component and a factual component. But, for all its a priori reasonableness, a boundary between analytic and synthetic statements simply has not been drawn. That there is such a distinction to be drawn at all is an unempirical dogma of empiricists, a metaphysical act of faith.
Quine exposes the fundamental weaknesses inherent in a linguistic approach to analyticity.
If this can be paraphrased as 'every meaningful statement is synonymous with a statement about immediate experience,' then we have returned to the unsound notion of synonymy. Also important to note is the move away from synonymy of words to synonymy of statements. Carnap, in his Aufbau , attempted to translate all meaningful statements into an immediate sensation language. Although this method seems plausible, his system falls when one looks at the predicate of this sentence. Even if one tries to soften reductionism, Quine claims one will encounter the same problem.