This lecture closes a six-yearteachingcycle by revisiting the principle of international law that has been the guiding thread : sovereignty. Now claimed as an irresistible fact or, on the contrary, rejected as outdated, sovereignty, whose concept is nonetheless normative, has curiously rarely been justified or criticized in its justifications - at least, until recently. Even in the light of the many theories of the political legitimacy of international law and its institutions. This year's lecture proposes a reinterpretation of sovereignty in the plural, with reference, on the one hand, to the equality of peoples whose self-determination is guaranteed by international law and, on the other, to the plurality of institutional forms that the exercise of their self-determination can and must take under international law in the future.
The annual colloquium devoted to the controversial issue of property in space proposes to revisit state sovereignty, this time in space and in its articulation with territorial jurisdiction and private property and, more generally, with the project of instituting spatial commons in international law.