In the Preface to his recent book, Samples of Lawmaking, Lord Devlin rather sadly doubted “whether judges will now of their own motion contribute much more to the development of the law. Statute,” he said, “is a more powerful and flexible instrument for the alteration of the law than any that a judge can wield.” Since those words were written Lord Devlin has himself contributed to some substantial judicial reforms of the law, notably in Rookes v. Barnard and Hedley Byrne & Co. Ltd. v. Heller & Partners Ltd., but it does, of course, remain true that it is very much easier for the legislature than for any court, however strong, to bring changes to the law. It is also true, generally at least, that when we speak of law reform we mean reform by statute and we try to formulate in a draft Bill the rules of law that we should like to see. To my mind, however, it is unfortunate that we so often try to find a formulation which provides in some detail for the particular situations we have in mind and which is designed to give the court the minimum opportunity for what is sometimes called creative interpretation. With a few exceptions—the Contributory Negligence Act and the Occupiers’ Liability Act are examples—we do not legislate in such a way as to give the judges a new principle expressed in general terms and leave it to them to work out the application of that principle in the cases that arise.