What an Agent Ought To Do

This paper reviewes Horty\u27s 2001 book `Agency and Deontic Logic\u27. We place Horty\u27s research I a broader context and discuss the relevancy for logics for multi-agent systems

Reasons for and reasons against

What an agent ought to do is determined by competition between reasons bearing on the options open to her. The popular metaphor of balancing or weighing reasons on a scale to represent this competition encourages a focus on competition between reasons for competing options. But what an agent ought to do also depends on the reasons against those options. The balancing metaphor does not provide an obvious way to represent reasons against. Partly as a result of this, there is a serious lack of work on reasons against. A simple view is that there is no problem here, since reasons against an option are really just more reasons for—in particular, reasons for certain alternatives. This simple view lets us maintain the balancing metaphor, and more importantly, it simplifies theorizing about the competition between reasons. This is because if it’s true, there is really just one kind of competition, the competition between reasons for competing options. This paper challenges the simple view, arguing against several ways of identifying which alternatives to an option the reasons against it are reasons for. I also sketch a competing view, according to which reasons against are distinct from reasons for—these are two different normative relations. If this kind of view is correct, then our theory of the competition between reasons will need to recognize at least two kinds of competition: the one between reasons for competing options, and the one between the reasons for an option and the reasons against it.Publisher PDFPeer reviewe

Deontic Modality and the Semantics of Choice

I propose a unified solution to two puzzles: Ross's puzzle and free choice permission. I begin with a pair of cases from the decision theory literature illustrating the phenomenon of act dependence, where what an agent ought to do depends on what she does. The notion of permissibility distilled from these cases forms the basis for my analysis of 'may' and 'ought'. This framework is then combined with a generalization of the classical semantics for disjunction — equivalent to Boolean disjunction on the diagonal, but with a different two-dimensional character — that explains the puzzling facts in terms of semantic consequenc

Prioritized Conditional Imperatives:Problems and a New Proposal

The sentences of deontic logic may be understood as describing what an agent ought to do when faced with a given set of norms. If these norms come into conflict, the best the agent can be expected to do is to follow a maximal subset of the norms. Intuitively, a priority ordering of the norms can be helpful in determining the relevant sets and resolve conflicts, but a formal resolution mechanism has been difficult to provide. In particular, reasoning about prioritized conditional imperatives is overshadowed by problems such as the `order puzzle\u27 that are not satisfactorily resolved by existing approaches. The paper provides a new proposal as to how these problems may be overcome

Prioritized Norms and Defaults in Formal Argumentation

International audienceDeontic logic sentences define what an agent ought to do when faced with a set of norms. These norms may come into conflict such that a priority ordering over them is necessary to resolve these conflicts. Dung’s seminal paper raises the still open challenge to use formal argumentation to represent non monotonic logics, highlight- ing its value to exchange, communicate and resolve possibly conflicting viewpoints in distributed scenarios. In this paper, we propose a formal framework to study various properties of prioritized non monotonic reasoning in formal argumentation, in line with this idea. More precisely, we show how a version of prioritized default logic and Brewka-Eiter’s construction in answer set programming can be obtained in argumentation via the weakest and last link principles. We also show how to represent Hansen’s recent construction for prioritized normative reasoning by adding arguments using weak contraposition via permissive norms, and their relationship to Caminada’s “hang yourself” arguments

Decision-Theoretic Consequentialism and the Desire-Luck Problem

Jackson (1991) proposes an interpretation of consequentialism, namely, the Decision Theoretic Consequentialism (DTC), which provides a middle ground between internal and external criteria of rightness inspired by decision theory. According to DTC, a right decision either leads to the best outcomes (external element) or springs from right motivations (internal element). He raises an objection to fully external interpretations, like objective consequentialism (OC), which he claims that DTC can resolve. He argues that those interpretations are either too objective, which prevents them from giving guidance for action, or their guidance leads to wrong and blameworthy actions or decisions. I discuss how the emphasis on blameworthiness in DTC constraints its domain to merely the justification of decisions that relies on rationality to provide a justification criterion for moral decisions. I provide examples that support the possibility of rational but immoral decisions that are at odds with DTC’s prescription for right decisions. Moreover, I argue what I call the desire-luck problem for the external element of justification criterion leads to the same objection for DTC that Jackson raised for OC. Therefore, DTC, although successful in response to some objections, fails to provide a prescription for the right decision

Ross on Duty and Ignorance

In his Foundations of Ethics, W. D. Ross continued to maintain the view, first developed in The Right and the Good, that "right" designates that which is morally suitable to the situation in which an agent finds himself.1 But, as Ross notes, more needs to be said since an agent's situation contains two elements. The objective element consists of facts about the persons and things involved in the situation. That act which in fact is morally suitable to the situation as it actually is represents the objective element and is said by Ross to be objectively right. The subjective element consists of the agent's thoughts about the situation. That act which the agent, in view of his beliefs about the situation, thinks is morally suitable is called by Ross subjectively right (FE, p. 146)

Contextualism and Knowledge Norms

I provide an opinionated overview of the literature on the relationship of contextualism to knowledge norms for action, assertion, and belief. I point out that contextualists about ‘knows’ are precluded from accepting the simplest versions of knowledge norms; they must, if they are to accept knowledge norms at all, accept “relativized” versions of them. I survey arguments from knowledge norms both for and against contextualism, tentatively concluding that commitment to knowledge norms does not conclusively win the day either for contextualism or for its rivals. But I also suggest that an antecedent commitment to contextualism about normative terms may provide grounds for suspicion about knowledge norms, and a debunking explanation of some of the data offered in favor of such norms

Taking Prudence Seriously

Philosophers have long theorized about which things make people’s lives go well, and why, and the extent to which morality and self-interest can be reconciled. Yet little time has been spent on meta-prudential questions, questions about prudential discourse. This is surprising given that prudence is, prima facie, a normative form of discourse and, as such, cries out for further investigation. Chapter 4 takes up two major meta-prudential questions. It first examines whether there is a set of prudential reasons, generated by evaluative prudential properties, and defends the view that evaluative well-being facts generate agent-relative reasons for the relevant agent. It also investigates whether prudential discourse is normative. It is proposed that prudential discourse is normative by arguing that prudential judgements are normative judgements. The case for this is presented by analogy with moral discourse by showing that the features of moral judgements that metaethicists appeal to when articulating, explaining, and justifying the claim that moral judgements are normative are also possessed by prudential judgements. Various objections to the analogy are also considered