Unum, Verum, Bonum and the System Formation of Critical Philosophy

Abstract This article deals with Kant’s intentions in adding § 12 of the second edition of the Critique of Pure Reason. Here, Kant remarks on the so-called transcendentals (unum, verum, bonum) in the metaphysical or ontological tradition. This article focuses on their trans-categorial character to clarify their role in the system formation of Kant’s three critiques. In order to clarify Kant’s difficult terminology in § 12, fragments from his reflections and transcripts of his lectures are analyzed. Furthermore, an examination of Kant’s references to qualitative unity, plurality, and perfection reveals that these logical criteria of cognition in general help him to organize the content of the three critiques.