Necessity for finite rational minds– Kant on empirical nomic necessity and the conceptual purposiveness of nature

Kant claims that empirical laws of nature “carry with them an expression of necessity” (Kant, 1998; A159/B198). What precisely is this “expression of necessity” and what grounds it? The metaphysical necessitation approach asks “What are laws of nature for Kant?” It answers that, for Kant, empirical laws possess necessity and are grounded in the properties and causal powers essential to natural kinds. The epistemological systematization approach claims that empirical natures, kinds and causal laws are rightly viewed as necessitating in virtue of the place they ideally take within an ultimate systematic conception of nature. The paper defends a hybrid transcendental-idealist approach to empirical necessity. It argues that Kant offers a transcendental deduction of the a priori principle of the systematic conceptual purposiveness of nature. In contrast to the systematization approach, this builds necessity into our most fundamental, conceptually articulated experience of nature. The approach can furthermore complement metaphysical necessitation accounts by showing that the commitment to necessitation follows from the metaphysical doctrine of transcendental idealism and the critical project of articulating the a priori transcendental conditions of experience. Recognizing the transcendental status of the principle of the systematic conceptual purposiveness of nature thus allows us to merge valuable insights of both the epistemological systematization and the metaphysical necessitation views.