On the Fourfold Root of the Principle of Sufficient Reason

§ 32 Transcendental Truth

The forms of intuitive, empirical knowledge which lie within the Understanding and pure Sensibility may, as conditions of all possible experience, be the grounds of a judgment, which is in that case synthetical à priori. As nevertheless this kind of judgment has material truth, its truth is transcendental; because the judgment is based not only on experience, but on the conditions of all possible experience lying within us. For it is determined precisely by that which determines experience itself: namely, either by the forms of Space and of Time perceived by us à priori, or by the causal law, known to us à priori. Propositions such as: two straight lines do not include a space; nothing happens without a cause; matter can neither come into being nor perish; 3 × 7 = 21, are examples of this kind of judgment. The whole of pure Mathematics, and no less my tables of the Prædicabilia à priori,131 as well as most of Kant’s theorems in his “Metaphysische Anfangsgründe der Naturwissenschaft,” may, properly speaking, be adduced in corroboration of this kind of truth.