When I was first called upon to lecture during the darkest days of the war in 1941, because Hersch Lauterpacht was on some mission, I was still surrounded by my own teachers—Buckland, Duff, Gutteridge and McNair (Hazeltine had left). Of these Gutteridge and McNair influenced me most—the former by convincing me that foreign law was well worth studying, if not for its own sake, then in order to test the validity of one's own cherished notions and established techniques and to acquire the inspiration for new solutions, but not in order to discover an all pervading droit commun legislatif. McNair impressed upon me the reality of the rules of international law in the practice of states and in the administration of law by domestic courts. Not monism of a doctrinaire kind, but the age old tradition of the common lawyer to interpret English law so as not to conflict with international law was his inspiration, which has guided me ever since. I must not omit two other formative influences from times long passed. My teachers in Berlin included the last “Pandectist” (Th. Kipp), the broadly based Romanist, Greek scholar and modern comparatist as well as innovator of private international law (Rabel), and the superb exponent of private and private international law (M. Wolff) whose nephew, I am happy to think, will continue the propagation of the work which has been carried out in Cambridge since 1930 by Gutteridge, Hamson and myself. Gutteridge, Rabel and Wolff, whose works in the English language have enriched the fund of the common law, probably gave me the foundations on which most of my own work is based.

A person who receives property under an apparent contract of sale can be guilty of theft of what he receives if the contract is void, for mistake or otherwise. It seems, since the decision of the House of Lords in Lawrence, that a person who obtains a voidable title (title under a voidable contract) can be similarly guilty (assuming, as always, that the other essentials of theft are present). I argue else where that a person who obtains a valid title to property generally does not by doing so make a dishonest appropriation (even though he may be morally dishonest), and should not be guilty of theft. The object of this article is to consider the way in which these principles apply to transfers made under mistake.

In Lawrence the defendant's title to the money was voidable for fraud, which induces a degree of mistake by the transferor; but other sources of mistake are possible. The transferor may make a spontaneous mistake, or a mistake resulting from the transferee's innocent misrepresentation, without fraud.

Three legal results can follow from a mistake in transferring property, according to circumstances.

(1) The mistake may avoid the transaction, preventing title from passing. The transferee can be guilty of theft of the property on ordinary principles, that is to say by applying the definition in section 1 (1) of the Theft Act 1968.

(2) The mistake may make the transaction voidable, so that a voidable title passes. Precisely when the transferee commits theft is a complex question, which will be postponed for the time being.

It is unlikely that those who were responsible for giving the World Court the power to indicate interim measures of protection could have anticipated the controversy which was ultimately to surround its exercise. Applications for interim measures have been few, even by the inexacting standards of international litigation, but the cases in which such measures have been sought have raised questions of fundamental importance. Controversial issues have included the power of the Court to indicate interim measures on its own initiative, the binding nature and enforceability of interim measures, their purpose and their relation to the Court's substantive jurisdiction, that is its jurisdiction to rule upon the merits of a dispute.

I. Introduction

The Philosophy of the law has largely accepted that laws are rules although it still struggles with the completeness of that paradigm. Nevertheles there has been no clear analysis for the law of what a rule is and what it entails. This paper is an attempt to do that.

The period from about 1300 to 1628 witnessed the beginnings of martial law, the establishment of custom governing the situations in which it might be invoked, then a break with that custom followed by a period of widened application, and finally, a reaction, once again restricting the Crown's use of martial law. Although extended, this period needs to be understood as a coherent whole, what might be termed, the first chapter in the history of martial law in England.