Inspired by legal reasoning, this paper presents a formal framework for assessing conflicting arguments. Its use is illustrated with applications to realistic legal examples, and the potential for implementation is discussed. The framework has the form of a logical system for defeasible argumentation. Its language, which is of a logic-programming-like nature, has both weak and explicit negation, and conflicts between arguments are decided with the help of priorities on the rules. An important feature of the system is that these priorities (...) are not fixed, but are themselves defeasibly derived as conclusions within the system. Thus debates on the choice between conflicting arguments can also be modelled.The proof theory of the system is stated in dialectical style, where a proof takes the form of a dialogue between a proponent and an opponent of an argument. An argument is shown to be justified if the proponent can make the opponent run out of moves in whatever way the opponent attacks. Despite this dialectical form, the system reflects a declarative, or relational approach to modelling legal argument. A basic assumption of this paper is that this approach complements two other lines of research in AI and Law, investigations of precedent-based reasoning and the development of procedural, or dialectical models of legal argument. (shrink)

We assume—in contrast to many “legal realists”—that law is a part of reality. Law exists because people believe in law, but law is not identical with beliefs. Law supervenes on human beliefs, preferences, actions, dispositions and artefacts. Moreover, the morally binding personal interpretation of the law supervenes on two things together: on the individual's knowledge of legal institutions and on moral obligation. The first supervenes in its turn on mutual beliefs; the second supervenes on motivations and dispositions of the individual, (...) provided that she is morally sensitive and rational. Personal interpretation of law converts into social law, if other persons on the basis of overriding reasons do not contest it. Morally binding social law supervenes on moral motivation that is triggered by institutions that supervene on mutual beliefs. (shrink)

The Concept of Law is the most important and original work of legal philosophy written this century. First published in 1961, it is considered the masterpiece of H.L.A. Hart's enormous contribution to the study of jurisprudence and legal philosophy. Its elegant language and balanced arguments have sparked wide debate and unprecedented growth in the quantity and quality of scholarship in this area--much of it devoted to attacking or defending Hart's theories. Principal among Hart's critics is renowned lawyer and political philosopher (...) Ronald Dworkin who in the 1970s and 80s mounted a series of challenges to Hart's Concept of Law. It seemed that Hart let these challenges go unanswered until, after his death in 1992, his answer to Dworkin's criticism was discovered among his papers. In this valuable and long-awaited new edition Hart presents an Epilogue in which he answers Dworkin and some of his other most influential critics including Fuller and Finnis. Written with the same clarity and candor for which the first edition is famous, the Epilogue offers a sharper interpretation of Hart's own views, rebuffs the arguments of critics like Dworkin, and powerfully asserts that they have based their criticisms on a faulty understanding of Hart's work. Hart demonstrates that Dworkin's views are in fact strikingly similar to his own. In a final analysis, Hart's response leaves Dworkin's criticisms considerably weakened and his positions largely in question. Containing Hart's final and powerful response to Dworkin in addition to the revised text of the original Concept of Law, this thought-provoking and persuasively argued volume is essential reading for lawyers and philosophers throughout the world. (shrink)

This book analyses the general structure of constitutional rights reasoning under the German Basic Law. It deals with a wide range of problems common to all systems of constitutional rights review. In an extended introduction the translator argues for its applicability to the British Constitution, with particular reference to the Human Rights Act 1998.