The books reviewed in this review essay, by Shany and Letsas highlight two increasingly significant dimensions ofinternational law: the interaction of national and international courts and the interaction of ideas and arguments. Together they substantiate quite convincingly the comment of Lord Bingham to the effect that although ‘international law comprises a distinct and recognizable body of law with its own rules and institutions, it is a body of law complementary to the national laws of individual states’, which ‘rests on similar principles
and pursues similar ends’. In their own ways both books point towards an emerging ‘substantive theory of international law’, which is also what Lord Bingham hinted at and
which perhaps follows the recent development of sophisticated theories of international
justice. It seems to me that both of these books show that in practice many courts— although not all of them—already work with some such substantive view of international law and ignore the theoretical model of ‘legal systems’. Although—as far as I know—we do not yet have consensus on a clear theoretical paradigm or articulation of this view of public international law, one that tackles the problem of ‘the law of laws’ directly and with the appropriate ambition, the books by Shany and Letsas can well be seen as the eloquent and path-breaking supporters of such an enterprise, the sophisticated avantgarde for a view of international institutions whose time has come.
P Eleftheriadis, 'The Law of Laws' (2010) 1(4) Transnational Legal Theory 597–618.