When Deleuze wishes to provide a critique of the transcendental ego, it is Sartre's early essay, The Transcendence of the Ego, that he turns to in order to justify his move to a conception of the transcendental free from subjective notions. The aim of this essay is to show the purpose for which Deleuze uses Sartre's critique of Husserl against Kant, and to show the interrelation between this critique and the establishment of transcendental empiricism. Deleuze gives Kant the status of an enemy, a term that carries with it the full weight of his estimation of, as well as opposition to the transcendental idealist project. Deleuze's own transcendental empiricism rests on the rejection of two of the fundamental tenets of transcendental idealism, first, the claim that "the conditions of the object of knowledge must be the same as the conditions of knowledge,"1 and its corollary, the necessity of the transcendental ego in organizing the transcendental field. Deleuze believes that these two claims in fact imply one another, so that a rejection of one forces us also to reject the other. If this is correct, it would mean that The Transcendence of the Ego would implicitly contain the major axioms of the Deleuzian system, particularly the division between actual states of affairs and virtual singularities. The aim of this paper is therefore to outline the structure of the SartreDeleuze argument, and then to show how Deleuze's claims are in fact, a little optimistic. Central to this analysis will be both Sartre and Deleuze's responses to Kant, and in particular to the argument of the transcendental deduction. The transcendental deduction is the centerpiece of the Critique of Pure Reason, attempting to show that experience is grounded in the categories, transcendental correlates of the logical structures of judgment. The argument proceeds by showing that the unity which is inherent in experience (as shown by the fact that "it must be possible for the ? think' to accompany all my representations.")2 indicates a synthetic unity at the transcendental level, and that this unity can only operate through structures parallel to those which govern the judgments of the understanding (as judgment itself generates unities in the form of propositions). Thus, for Kant, the transcendental field is individuated (it contains a transcendental ego) and structured in a way which parallels the empirical world (the categories are derived from the functions of judgment). For Sartre, the difficulty with this argument is that it fails to recognize the possibility of the object itself providing the grounds for the unity of experience, thus Sartre will take issue with the need for the ? think' having a transcendental correlate. Deleuze, on the other hand, is opposed to any form of individuation of the transcendental field, arguing that if the transcendental field is individuated, the question of the genesis of form itself becomes impossible to deal with, as it is already presupposed within the transcendental field. Deleuze presents this move as a move from transcendental idealism to a form of transcendental empiricism, as the conditions of experience now lie outside of a subject. In reconstructing a move from Transcendental Idealism to Transcendental Empiricism through Sartre's critique of the Transcendental Ego3, there are three difficulties that must be overcome. First, there is the schematic nature of the references to Sartre in Deleuze's writings. Whilst Deleuze credits Sartre with providing a "decisive"4 critique of the notion of a transcendental subject, Deleuze provides almost no commentary on the text itself. This presents difficulties as the text, as it stands, is not overtly critical of Kant, its target rather being the Transcendental Ego of Husserl. second, although Sartre's essay is clearly aimed at a Husserlian conception of the ego, Sartre's intention in this essay is not to critique phenomenology itself. His statement that "all the results of phenomenology begin to crumble if the I is not, by the same title as the world, a relative existent,"5 is followed by an attempt to reconfigure the transcendental ego in order to give it such a nature, and in the process to preserve the results in question. …