This paper offers a critique of Christine Korsgaard’s interpretation of Kantian instrumental reason. Korsgaard understands Kantian hypothetical imperatives to share a common normative source with the categorical imperative – namely self-legislating, human rational agency. However, her reading of Kantian hypothetical imperatives is problematic for three reasons. Firstly, Korsgaard’s agent-centred approach renders incoherent Kant’s analytic-synthetic division. Secondly, by minimising the dualistic framework of Kant’s practical philosophy the dialectical character of practical rationality is lost: norms of instrumental reasoning therefore become confused with (...) those of moral reasoning. Thirdly, this in turn curtails the distinct critical authority of pure practical rationality over instrumental choice. The paper argues that we need to understand the normativity of instrumental rationality through the lens of Kant’s dualisms. An alternative interpretation is offered which highlights how the norms of hypothetical imperatives appeal to standards of theoretical cognition and practical efficiency rather than the self-legislative demands of pure practical reason. (shrink)