The editors of the Harvard Law Review respectfully dedicate this issue to Professor Ronald Dworkin. Richard H. Fallon, Jr * My first exposure to Ronald Dworkin came at Oxford, in the fall of 1975. Although I was there to study Philosophy, Politics, and Economics, not Law, friends told me that Professor Dworkin's packed lectures on jurisprudence were not to be missed. They were right. Dworkin delivered the most commanding lectures that I had ever heard, at Oxford or anywhere else. Plainly relishing the engagement of his rapt audience, and speaking entirely without notes, he worked his way through, and demolished, various thinkers' accounts of what made it the case, if it was the case, that "The law is that P." The critiques built inexorably to the conclusion that first made Dworkin famous: decision of hard cases requires a process of interpretation in which principles, not just "pedigreed" rules, help to make it the case, if it is the case, that "The law is that P." In one way, Dworkin was the very model of an Oxford philosopher. Though dense, his arguments were clear. He was a master of distinctions. But in another way, Dworkin was a gust of fresh air blowing through the ancient university during my two years there. To make his points, he used vivid, often funny examples. After skewering one position or another, he would pause to invite questions and challenges. Challenges came frequently because Dworkin's largest target was his eminent predecessor as Oxford's Professor of Jurisprudence, H. L. A. Hart. At that time and in that setting, however, taking on Dworkin in public debate was a fool's errand. Without fail, he would flatter the challenge, briskly restate it, and then quickly identify some stark fallacy at its heart, some untenable premise, some plain logical mistake. The 1970s were tough times for England, with the pound swooning and the economy--and sometimes governments--at the mercy of truculent unions. Though I loved Oxford, it was nearly always gray and often cold, and more than a few of the British seemed to relish the task of chastening American ambition. To young Americans there studying Law, or Philosophy, Politics, and Economics, Dworkin personified vitality, panache, and undaunted intellectual ambition. We not only flocked to his lectures, but also awaited--and then breathlessly discussed--his articles in the New York Review of Books. As a frequent speaker before formal and informal groups, Dworkin was generous with his time, funny, and warm. After leaving Oxford, I did not again have any personal encounter with Professor Dworkin for many years. I never knew him at all well. When I departed from Oxford in 1977 to attend law school, I did so with a strong interest in jurisprudence, the field that Dworkin had energized by initiating "the Hart-Dworkin debate." In law school and then in my professional career, other subjects, including constitutional law, engaged me more. Nevertheless, throughout my professional life, I have always had the acute, inescapable sense of working in the shadow of Dworkin's influence. In the study of American constitutional and statutory interpretation, Dworkin, in my estimation, has no serious rival as the most incisive and fertile theorist of the past four decades. In those fields, the question that he pressed in Oxford lecture halls in the 1970s never loses its freshness, even if answers change: By virtue of what is it the case, if indeed it is the case, that "The law is that P"? Dworkin's arguments about the connections between constitutional and statutory interpretation, on the one hand, and political morality, on the other, have had a profound and continuing influence. In his wake, one must either embrace his views about the irreducibly moralized character of legal interpretation, and about the need to interpret legal practice in order to appraise what count as good arguments within it, or fight against his position. For example, even the best constitutional "originalists" now acknowledge that they must advance a normative defense of their position, not stop with the claim--as many once did--that the meaning of the Constitution just is, apparently necessarily, what those who wrote or ratified relevant provisions intended or understood it to be. …