AN inaugural lecture is the occasion when the University of Cambridge can look its gift horse in the mouth, weighing the new professor in the balance against his or her distinguished predecessors. The Rouse Ball Professorship of English Law has been held in the past by a long series of distinguished scholars, from Sir Percy Winfield to my immediate predecessor, Sir Jack Beatson whom we are delighted to welcome back today. Their work has influenced generations of lawyers. They certainly influenced me. Before I encountered Criminal Law: The General Part, a great little volume by Professor Glanville Williams, Learning the Law, was my “Guide, Philosopher and Friend” (as it still says on the cover of the latest edition, now edited by my colleague Professor Tony Smith) as I approached the study of law. Another Rouse Ball Professor, the late Sir William Wade, had a formative effect on my understanding of land law and administrative law both through his famous books, Megarry and Wade on the Law of Real Property (now edited by a former Fellow of Downing College, Dr. Charles Harpum) and Administrative Law (now in the hands of my colleague Dr. Christopher Forsyth), not to mention the lectures that I attended as an undergraduate in (softly be it said) the University of Oxford.