The broadly Kantian perspective woven into Deleuze's reading of the Humean story of the subject's emergence from the flux of becoming through the sedimentation of habits is at bottom a story about the unfolding drama of the relationship between passive and active faculties. In his early work, Deleuze employs the notion of the faculties in order to ask the question of what bodies can do. The analysis of the faculties, of the passive syntheses that become activated through the recursivity of Ideas, reveals simultaneously the constituting forces of common sense and the vital, revolutionary forces of thinking. This is fundamental to the project of philosophy itself, conceived by Deleuze as the contestation of doxa through the creation of concepts. In his book on Foucault, Deleuze asks, ‘What is philosophy today … if it is not the critical work that thought brings to bear on itself? In what does it consist, if not in the endeavour to know how and to what extent it is possible to think differently, instead of legitimating what is already known?’ (F 8–9).

Of course, this story has multiple layers, none of which should be ignored. Everything from Deleuze's reclamation of a ‘minor’ history of philosophy, to the material conditions of his life, to the art, science and mathematics that formed his cultural and intellectual milieu are indispensable for appreciating the richness and complexity of his stories. Here, the layer under investigation is primarily the Kantian one. However, in bringing to light the radical practice of critique woven throughout Deleuze's work, it is also necessary to confront the possibility of its Kantian contamination. The reason for this is simple and widely appreciated. Taking Kant's philosophy as one's starting point introduces a number of problematic assumptions into one's own work. It is impossible, as Robert Bernasconi has eloquently argued, to analytically split off the preferred part of Kant's work without bringing the Eurocentric, racist and misogynist parts with it. This is a difficulty that must be addressed directly. If Deleuze is utilising a Kantian perspective at the very foundation of his theory of subject formation, the question must be posed of whether this condemns his philosophical project to the same failures that he and many others have diagnosed in Kant. The answer to this question will have a significant impact on any project that attempts to build on Deleuzian insights.