H. Mendelson, Maurice Keywords: International customary law | Public international law | Mots clefs: Droit coutumier international | Droit international public | ABSTRACT Maurice Mendelson, professor at University College, London, insists in his course on the formation of customary international law on the fact that when we think of customary law-making in the international community, we should be thinking less of the modern legal process than of the customary domestic societies which existed everywhere in the past, b…