Many philosophers still believe that metaphysically analytic sentences exist, where a sentence is understood to be metaphysically analytic if and only if it is true solely in virtue of its meaning. I provide two arguments against this claim and hence conclude that metaphysically analytic sentences do not exist. Still, some philosophers, however, hold out hope that epistemically analytic sentences exist, where a sentence is epistemically analytic if and only if an agent's understanding the sentence suffices for the agent to be (...) justified in believing that this sentence is true. One such philosopher is Paul Boghossian, whose so-called analytic theory of the a priori is intended to show how epistemically analytic sentences can explain our a priori knowledge of the truths about logic. His theory, however, relies on the dubious Argument by Implicit Definition. I provide an objection to this argument and hence conclude that Boghossian's analytic theory of the a priori fails to vindicate the notion of epistemic analyticity. Still, I concede that just because Boghossian's attempt to do so fails, it does not follow that the notion of epistemic analyticity cannot, in another way, be vindicated. (shrink)