Catherine Malabou’s Before Tomorrow: Epigenesis and Rationality represents a new contribution to a series of books by critical theorists seeking to assess the relationship between Kant’s thought and contemporary critical thinking. My review proceeds in three steps. First, I contextualize the book by contrasting its approach to that of its antecedents. Second, I reconstruct Malabou’s central argument, according to which Kant’s notion of an “epigenesis of reason,” as presented in the Critique of Pure Reason, can be read as a movement of self-appropriation and self-formation by reason, which becomes evident in the Critique of the Power of Judgment. I focus on how this reading leads to a polemic engagement with Quentin Meillassoux’s critique of Kant, which, according to Malabou, is unable to provide a coherent account of the tension between necessity and contingency in the forms of thought. Third, I develop a critical assessment of both Meillasssoux’s and Malabou’s readings of Kant. By reconstructing Kant’s own reformulations of the distinction between necessity and contingency throughout his theoretical and practical philosophy, I show that both theorists leave aside an essential tenet of his critical enterprise, namely, the detachment of the realm of freedom and action from the realm of cognition. Thus I conclude that, although Malabou is right in that the categories of necessity and contingency are subject to an open-ended transformation in the cognitive realm, the development of these categories in Kant’s work is closely linked to his conception of action, which stems from the gap as well as the interrelation between theoretical and practical reason.