SummarySubjecting to a detailed analysis Kant's diagnosis of dialectical error in the Transcendental Dialectic of the first Critique, the author posits that Kant's understanding of such error is, to the extent that it conflates the subjective‐objective, phenomenal‐noumenal, and regulative‐constitutive distinctions, fundamentally incoherent. The author argues not only that these three distinctions cannot on Kant's own terms be conflated, but also that Kant's treatment of dialectical error is further vitiated by circularity of argument: Kant proposes to explain the three distinctions by (...) means of the notion of transcendental error, which however the distinctions themselves were supposed to explain in the first place. After showing that Kant's diagnosis of dialectical error cannot be salvaged even by resorting to the Kantian concept of “transcendental subreption”, the author concludes that unless Kant could in some other way spell out the minimal conditions for dialectical error, Kant's very distinction between understanding and reason becomes difficult to justify. (shrink)