In order to make "headway" in one of the most intractable debates in our field - the nature and workings of customary international law - authors seem to employ one of three tactics. One is to repeat and rehash the same narrow, doctrinal debates that scholars have been having for the last forty-odd years.1 Another and far more courageous approach is for the author to seek to completely re-imagine (and remake) customary international law.2 A third, finally, is to reflect on the nature of customary law more widely and to include insights from jurisprudence/legal theory, legal history, and moral/political philosophy.
An example of that third approach is the book under review, The Nature of Customary Law, edited by Amanda Perreau-Saussine and James Bernard Murphy and based on a conference at the University of Cambridge in 2005. It is decidedly the most notable and the most accomplished project in recent years. The two editors have assembled 13 authors, who have undertaken to elucidate certain historical and philosophical/theoretical aspects of the problematique resulting, it must be said, in a very well-executed bricolage. The more pragmatic readers are warned at the outset that neither is it a book on customary law in international law nor, for the most part, does it purport to describe how customary law comes about or is ascertained. But, as mentioned above, this was a conscious choice and one that has a great deal of merit. Beyond international legal scholarship and practice's narrow account lie the very rich "domestic" debates in the common law culture as well as parallel efforts in moral philosophy and (legal) historiography. The conscious decision of the editors to take account of these debates, coupled as it is with their choice of collaborators, does result, however, in a significant cultural bias ...