On the currently dominant reading of the Groundwork, Kant’s derivation of ‘imperatives of duty’ exemplifies a decision procedure for the derivation of concrete duties in moral deliberation. However, Kant’s response to an often-misidentified criticism of the Groundwork by G. A. Tittel suggests that Kant was remarkably unconcerned with arguing for the practicality of the categorical imperative as a decision procedure. Instead, I argue that the main aim of Kant’s derivation of imperatives of duty was to show how his analysis of the form of moral judgement is indeed presupposed in the four types of moral imperative that philosophers of his time recognized.