This paper addresses the two extensional objections to the Humean Theory of Reasons—that it allows for too many reasons, and that it allows for too few. Although I won’t argue so here, manyof the other objections to the Humean Theoryof Reasons turn on assuming that it cannot successfully deal with these two objections.1 What I will argue, is that the force of the too many and the too few objections to the Humean Theorydepend on whether we assume that Humeans are (...) committed to a thesis about the weight of reasons—one I call Proportionalism. In particular, I’ll show how a version of the Humean Theorythat rejects Proportionalism can reasonablyhope to escape both the too many and the too few objections. This will constitute my defense of this version of the Humean Theory. But then, separately, I will argue that this defense of the Humean Theoryis not ad hoc. I’ll argue that Humeans have no reason to accept Proportionalism in the first place. Or at least, no weightyone. There are three parts to the paper. In Part 1 we introduce the Humean Theoryand the too few reasons objection. I’ll first layout the objection, and then layout the basis for a response on behalf of myfavored version of the Humean Theory. There will be an obvious objection to my defense— but it will turn out to depend on the assumption of Proportionalism. This will constitute myargument that the susceptibilityof the Humean Theoryto.. (shrink)

Particularists in ethics emphasize that the normative is holistic, and invite us to infer with them that it therefore defies generalization. This has been supposed to present an obstacle to traditional moral theorizing, to have striking implications for moral epistemology and moral deliberation, and to rule out reductive theories of the normative, making it a bold and important thesis across the areas of normative theory, moral epistemology, moral psychology, and normative metaphysics. Though particularists emphasize the importance of the holism of (...) the normative, however, it is not something that they have been able to explain. In this paper I’ll show how to use a small number of simple and, I’ll argue, independently compelling assumptions in order to both predict and explain the holistic features of the normative with respect to the non-normative. The basic idea of the paper is simple. It is that normative claims are holistic because they are general, rather than because they defy generalization. (shrink)

From a philosophical standpoint, the work presented here is based on van Fraassen [26]. The bulk of that paper is organized around a series of arguments against the assumption, built into standard deontic logic, that moral dilemmas are impossible; and van Fraassen only briefly sketches his alternative approach. His paper ends with the conclusion that “the problem of possibly irresolvable moral conflict reveals serious flaws in the philosophical and semantic foundations of ‘orthodox’ deontic logic, but also suggests a rich set (...) of new problems and methods for such logic.” My goal has been to suggest that some of these methods might be found in current research on nonmonotonic reasoning, and that some of the problems may have been confronted there as well.I have shown that nonmonotonic logics provide a natural framework for reasoning about moral dilemmas, perhaps even more useful than the ordinary modal framework, and that the issues surrounding the treatment of exceptional information within these logics run parallel to some of the problems posed by conditional oughts. However, there is also another way in which deontic logic might benefit from a connection to nonmonotonic reasoning. A familiar criticism among ethicists of work in deontic logic is that it is too abstract, and too far removed from the kind of problems confronted by real agents in moral deliberation. It must be said that similar criticisms of abstraction and irrelevance are often lodged against work in nonmonotonic reasoning by more practically minded researchers in artificial intelligence; but here, at least, the criticisms are taken seriously. Nonmonotonic logic aims at a qualitative account of commonsense reasoning, which can be used to relate planning and action to defeasible goals and beliefs; and at least some of the theories developed in this area have been tested in realistic situations. By linking the subject of deontic logic to this research, it may be possible also to relate the idealized study of moral reasoning typical of the field to a more robust treatment of practical deliberation. (shrink)

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)

The Pleadings Game is a major contribution to artificial intelligence and legal theory. The book draws on jurisprudence and moral philosophy to develop a formal model of argumentation called the pleadings game. From a technical perspective, the work can be viewed as an extension of recent argumentation-based approaches to non-monotonic logic: (1) the game is dialogical rather than mono-logical; (2) the validity and priority of defeasible rules is subject to debate; and (3) resource limitations are acknowledged by rules for fairly (...) dividing the burdens of representation and proof among the players. Gordon's work evaluates important jurisprudential theories of argumentation and reasoning in the context of the U.S. commercial law on secured transactions. Audience: It is not necessary to have a formal background in law to appreciate The Pleadings Game. It will be of equal interest to both the artificial intelligence community and legal theorists. (shrink)