 Logical positivism affirmed that, given a language \(\mathbf{L}\), all a priori knowledge is analytic and all synthetic knowledge is a posteriori, thus denying the existence of knowledge that is both synthetic and a priori. Indeed, the denial of the existence of synthetic a priori knowledge is commonly assumed to define the position known as “Empiricism”, while the affirmation of its existence defines “Rationalism”. Figure 1 thus reflects the intersection of kinds of sentences and kinds of knowledge on the Empiricist approach: