Abstract: Can a parallel be drawn between the weaknesses of a certain Cartesian conception of human individuals’ interiority, on the one hand, and the problems facing a “holistic” conception of political groups, viewed as “collective individuals” and as possessors of group interiority, on the other hand? The answer is no. In the context of the debate surrounding cosmopolitanism, this article argues that in political philosophy, one cannot do without the intertwined modern ideas of Nation and Sovereignty.