In the context of Kantian philosophy, the articulation of moral, historical, juridical and political arguments, paves the way to the delineation of a practica1 political system. This article attempts to show how the political theses of The perpetual peace (defense of Republicanism, illegitimacy of Revolution, proposal of an inter-statal Constitution, a cosmopolitan Constitution, legitimacy of the citizens resistance through public expression, sense of political morality) found insertion in the critical framework that, illuminated by the categorical imperative, and the principle of finality, makes possible the Autonomy of will and the goals of pure reason.