Section 1 introduces the notion of transcendental arguments as arguments from the necessary conditions of possibility. What distinguishes them from other forms of deductive reasoning is the so-called transcendental conditional of the logical form ‘p is possible only if q’. Section 2 outlines three models for such arguments, analysing transcendental conditionals in terms of material implication, strict implication, and presupposition (semantic and pragmatic). Section 3 considers competing interpretations of Kant’s Refutation of Idealism presented in the B-edition of the Critique of Pure Reason. Section 4 summarises the main results of the paper.
