, transnational corporations, etc., presently participate in international law, as do indigenous
peoples and minority groups. This ﬂexibility is reﬂected only to a limited
extent in current articulations of sourcesofinternationallaw.6 The entities
do not all participate in the same way: State rights are not the same as for
After N. Bobbio, The Age of Rights (Cambridge, Polity Press, 1996).
Article 4.1 of the UN Charter.
In a vast literature, one of the best general accounts remains that by A. Cassese,
Self-Determination of Peoples: A Legal Reappraisal (Cambridge
have stressed and stretched two distinct but related areas of international law: the right of self-defence, and the rules of international humanitarian law. I conclude by arguing that even a disproportionately powerful state is constrained, in its ability to change international law, by the actions of other countries and public opinion – both at home and abroad.
There are two principal sourcesofinternationallaw. ‘Customary international law’ is an informal, unwritten body of rules deriving from a combination of ‘state practice’ and opinio juris . State
during his lifetime, and translated into French and English. 68 Fiore, whose work anticipated the international
law of human rights, 69 was of the view
that the ultimate sourceofinternationallaw was the juridical conscience of
European peoples. 70 Human society was
‘universal’ but only fully civilized states could be members of what
he called the Magna civitas , the juridical community. He had doubts whether
civilization could extend uniformly to all parts of the