Abstract The article discusses the role of Immanuel Kant’s practical philosophy in recent attempts to reformulate the critique of instrumental reason formulated by Max Horkheimer from a metaethical point of view. Here, the focus is on the determination of the relationship between normative and rational aspects with regard to the deontological conception expressed by the imperatives. Using the example of the differing readings of Christine Korsgaard and Konstantin Pollok on the relevance of the hypothetical imperative introduced by Kant in the second section of the Grundlegung zur Metaphysik der Sitten for questions concerning metaethics and the theory of action, the author shows that Kant’s practical philosophy can be interpreted both as an affirmative theory and as a criticism of instrumental reason. With Pollok, the article argues on the one hand for a reading of Kant that emphasises the prevalence of the categorical imperative over the instrumental forms of action. Simultaneously, it points to the problems of relating Kantian theorems to the socio-philosophical problems of a critique of instrumental reason that takes an overarching view of philosophical, scientific and social developments.