Quine is a complete empiricist, unlike rationalist such as Leibniz, Kant, Chomsky, here in Two Dogmas essentially he claims there are no "analytic" truths, but all truths involve an empirical aspect. Any possible meaning eventually comes from some sensory experience. If we haven't lived this life so far, how can we know bachelor is just a synonymy of unmarried? Accepting analyticity for Quine really means accepting rationalism which instead accepts meaning can be acquired from reason alone, no need for any experience. Even for the normal analytic tautology such as x=x is synthetic for Quine, since if you don't have some life experience how can you be sure a thing always equals itself even at a same time instant? How can you even know what equality (=) means without any sensory experience? How can you even know what simultaneity means without sense experience? (remember Special Relativity hinted most people didn't really understand the subtle motion-dependent relative nature of simultaneity)
So Quine want to discard the two unempirical dogmas left in logical empiricism to favor his more thorough pragmatism:
Carnap, Lewis, and others take a pragmatic stand on the question of choosing between language forms, scientific frameworks; but their pragmatism leaves off at the imagined boundary between the analytic and the synthetic. In repudiating such a boundary I espouse a more thorough pragmatism. Each man is given a scientific heritage plus a continuing barrage of sensory stimulation; and the considerations which guide him in warping his scientific heritage to fit his continuing sensory promptings are, where rational, pragmatic.
Of course, later Saul Kripke proposed his famous rigid designators to try to preserve some analyticity (rationality)...