Altruism, solidarity, and the nation state according to Thomas Nagel - The limits of rationality as the limits of justice?

This paper reconstructs the way Thomas Nagel connects metaphysical, epistemic and moral solipsism, and rejects them by a rationalist defence of objectivity, altruism and impartiality. It shows that these theses do not, however, lead to cosmopolitanism: Nagel limits impartial justice to solidarity and political interiority. This paper criticizes the presuppositions of this last limitation, and defends the coherence of cosmopolitanism with his anti-solipsist theses.