Abstract

The main thesis defended in this paper is that Hildebrand’s distinction between what we could call quiddities—or “quasi-essences,” endowed with chaotic and accidental unity—and genuine essences possessing an intrinsically necessary unity, grounds the radical distinction between analytic and synthetic a priori knowledge. This thesis has not been expressly emphasized by Hildebrand himself. In order to prove it, we: (1) relate the three types of unities distinguished by Hildebrand with the three kinds of judgments discriminated by Kant; (2) outline what we can call the “crux of empiricism”; (3) analyze four characteristic examples of synthetic a priori judgements; and (4) elaborate a provisional typology of synthetic a priori propositions, trying to include in it Hildebrand’s favorite examples.