Ethical thought is articulated around normative concepts. Standard examples of normative concepts are good, reason, right, ought, and obligatory. Theorists often treat the normative as an undifferentiated domain. Even so, it is common to distinguish between two kinds of normative concepts: evaluative or axiological concepts, such as good, and deontic concepts, such as ought. This encyclopedia entry discusses the many differences between the two kinds of concepts.

The article offers an overview of the deontic theory developed by the philosophical school of Mīmāṃsā, which is, and has been since the last centuries BCE, the main source of normative concepts in Sanskrit thought. Thus, the Mīmāṃsā deontics is interesting for any historian of philosophy and constitutes a thought-provoking occasion to rethink deontic concepts, taking advantage of centuries of systematic reflections on these topics. Some comparison with notions currently used in Euro-American normative theories and metaethical principles is (...) offered in order to show possible points of contact and deep divergences. In more detail, after an introduction explaining the methodology and aims of our work, we discuss how Mīmāṃsā authors distinguished and defined some fundamental deontic concepts, such as different types of prescriptions and prohibitions. We then discuss how Mīmāṃsā authors approached the problem of conflicts among commands without jeopardising the validity of the normative text issuing them. In the second part of the article we introduce our formal apparatus, which is construed around the main taxonomic and conceptual distinctions used in the first part. Our formal rendering captures the most important features of the Mīmāṃsā theory and can thus serve as a concise and rigorous presentation of it for scholars working in deontic logic. (shrink)

Despite recent research showing that children rapidly interpret human action in terms of intention, a long tradition of empirical research on moral development and recent conceptual analyses of the deontic domain suggest that children do not apply their understanding of intention to the deontic domain. However, two experiments are described showing that children do make that connection. Preschool children heard stories in which a protagonist was obliged to meet a particular condition if an action was to be taken (e.g. obliged (...) to wear a coat if playing outside). When shown four pictures depicting each possible combination of: (1) the protagonist either performing the action or not, and (2) deliberately or accidentally failing to meet the obligation, children appropriately identified the protagonist as naughty when he or she was depicted as deliberately not meeting the obligation while performing the action. The findings proved to be robust across two different cultural settings. Implications for research on children’s developing theory of mind and their understanding of deontic concepts are discussed. (shrink)

Despite recent research showing that children rapidly interpret human action in terms of intention, a long tradition of empirical research on moral development and recent conceptual analyses of the deontic domain suggest that children do not apply their understanding of intention to the deontic domain. However, two experiments are described showing that children do make that connection. Preschool children heard stories in which a protagonist was obliged to meet a particular condition if an action was to be taken (e.g. obliged (...) to wear a coat if playing outside). When shown four pictures depicting each possible combination of: (1) the protagonist either performing the action or not, and (2) deliberately or accidentally failing to meet the obligation, children appropriately identified the protagonist as naughty when he or she was depicted as deliberately not meeting the obligation while performing the action. The findings proved to be robust across two different cultural settings. Implications for research on children’s developing theory of mind and their understanding of deontic concepts are discussed. (shrink)

The present article provides a taxonomic analysis of bimodal logics of normative ideality and normative awfulness, two notions whose meaning is here explained in terms of the moral values pursued by a given community. Furthermore, the article addresses the traditional problem of a reduction among deontic concepts: we explore the possibility of defining other relevant normative notions, such as obligation, explicit permission and Hohfeldian relations, in terms of ideality and awfulness. Some proposals in this respect, which have been formulated (...) in the literature over the years, are here improved and discussed with reference to the various logics that we will introduce. (shrink)

Theories of epistemic justification are usually described as belonging to either deontological or nondeontological categories of justification with the former construing the concept of justification as involving the fulfillment of epistemic duty. Despite being the dominant view among traditional epistemologists, the deontological conception has been subjected to severe criticisms in the current literature for failing, among others, to do justice to the (alleged) truth-conducive character of epistemic justification. In this paper I set out to show that there is something deeply (...) unsatisfying about the way these different conceptions of justification are usually introduced and contrasted with each other leaving it unclear just what it is that renders a particular conception deontological. In particular I look at Alston's treatment of the issue, and show that his reasons for rejecting the deontological conception involve question-begging assumptions demonstrating, at best, the possibility of its divergence from truth-conductive justification. Far from being able to settle the issue one way or another, the arguments, I shall suggest actually seem to show some sort of tolerant pluralism in justification theory to be a live option. (shrink)

This chapter contains sections titled: Introduction On Law and Morality Legal Rights and Legal Principles Law and Legal Systems Deontic Logic and Legal Philosophy Philosophical Doctrines in Latin America Conclusion References.

A considerable number of books and papers have analyzed normative concepts using new techniques developed by logicians; however, few have bridged the gap between the English legal culture and the Continental tradition in legal philosophy. This book addresses this issue by offering an introductory study on the many possibilities that logical analysis offers the study of legal systems. The volume is divided into two sections: the first covers the basic aspects of classical and deontic logic and its connections, advancing (...) an explanation of the most important topics of the discipline by comparing different systems of deontic logic and exploring some of the most important paradoxes in its domain. The second section deals with the role of logic in the analysis of legal systems by discussing in what sense deontic logic and the logic of norm-propositions are useful tools for a proper understanding of the systematic structure of law. (shrink)

This article contains an overview of the author's long‐standing involvement with deontic logic, both from a technical and from a wider philosophical point of view. As far as the formal aspects of deontic logic are concerned, the author describes his intellectual development from the original discovery of the analogy between modal (and deontic) notions on the one hand, and quantifiers on the other, through the formulation of a systematic theory of dyadic deontic concepts, to the proposal of a formal (...) logic of action as a foundation for deontic logic. In a more philosophical vein, the author discusses such questions as the very possibility of deontic logic if norms have no truth‐value, the relation between the descriptive interpretation of classical deontic logic and the logic of norm‐propositions, the correct representation of conditional or hypothetical norms, the distinction between moral obligation and practical necessity, and the interdefinability of permission and obligation. (shrink)

This volume contains the proceedings of DEON2020/2021, the 15th International Conference on Deontic Logic and Normative Systems that was organized by the Munich Center for Mathematical Philosophy at LMU Munich (Germany) on 21st-24th July, 2021. The biennial DEON conferences are designed to promote interdisciplinary cooperation amongst scholars interested in linking the formal-logical study of normative concepts, normative language and normative systems with computer science, artificial intelligence, linguistics, philosophy, organization theory, and law.

Deontic logic is an area of logic which investigates normative concepts, systems of norms, and normative reasoning. The word ‘deontic’ is derived from the Greek expression ‘déon’, which means ‘what is binding’ or ‘proper’. Thus, Jeremy Bentham used the word ‘deontology’ for “the science of morality,” and the Austrian philosopher Ernst Mally, who developed in the 1920s a system of the “fundamental principles the logic of ought,” called his theory ‘Deontik’. Normative concepts include the concepts of obligation (...) (ought), permission (may), prohibition (may not), and related notions, such as the concept of right. Systems of deontic logic contain, in addition to the usual sentential connectives and quantifiers, logical constants which represent some of these normative concepts. (shrink)

John Horty effectively develops deontic logic (the logic of ethical concepts like obligation and permission) against the background of a formal theory of agency. He incorporates certain elements of decision theory to set out a new deontic account of what agents ought to do under various conditions over extended periods of time. Offering a conceptual rather than technical emphasis, Horty's framework allows a number of recent issues from moral theory to be set out clearly and discussed from a uniform (...) point of view. (shrink)

An extraordinary amount of recent work by philosophers of language, meta-ethicists, and semanticists has focused on the meaning and function of language expressing concepts having to do with what is allowed, forbidden, required, or obligatory, in view of the requirements of morality, the law, one's preferences or goals, or what an authority has commanded: in short, deontic modality. This volume presents new work on the much-discussed topic of deontic modality by leading figures in the philosophy of language, meta-ethics, and (...) linguistic semantics. The papers tackle issues about the place of decision and probability theory in the semantics of deontic modality, the viability of standard possible worlds treatments of the truth conditions of deontic modal sentences, the possibility of dynamic semantic treatments of deontic modality, the methodology of semantics for deontic modals, and the prospects for representationalist, expressivist, and inferentialist treatments of deontic modality. (shrink)

Deontic reasoning is thinking about whether actions are forbidden or allowed, obligatory or not obligatory. It is proposed that social norms, imposing constraints on individual actions, constitute the fundamental concept for the system of these four deontic modalities, and that people reason from such norms flexibly according to deontic core principles. Two experiments are presented, one on deontic conditional reasoning, the other on “pure” deontic reasoning. Both experiments demonstrate people's high deontic competence and confirm the proposed representational and inferential principles. (...) Experiment 1 additionally shows small effects of the conditional formulations. These findings support the dual source approach (Beller & Spada, 2003) that distinguishes between domain-specific and domain-general inferences. Implications for other theories of deontic reasoning are discussed. (shrink)

Deontic Doxastic Constitutivism is the view that beliefs are constitutively governed by deontic norms. This roughly means that a full account and understanding of the nature of these mental attitudes cannot be reached unless one appeals to some norm of this type. My aim in this article is to provide an objection to such a conception of the normativity of belief. I argue that if some deontic norm is constitutive of belief, then the addressees of such a norm are committed (...) to a potentially infinite number of norms. Furthermore, if addressees are in the position to fulfill all such norms, they must also be able to hold a potentially infinite number of logically independent beliefs. Both these consequences are problematic if compared with limited human capacities to act and believe. (shrink)

The aim of this paper is to introduce a system of dynamic deontic logic in which the main problems related to the de finition of deontic concepts, especially those emerging from a standard analysis of permission in terms of possibility of doing an action without incurring in a violation of the law, are solved. The basic idea is to introduce two crucial distinctions allowing us to differentiate (i) what is ideal with respect to a given code, which fixes the (...) types of action that are abstractly prescribed, and what is ideal with respect to the specific situation in which the agent acts, and (ii) the transitions associated with actions and the results of actions, which can obtain even without the action being performed. (shrink)

Computational systems are traditionally approached from control-oriented perspectives; however, as soon as we move from centralized to decentralized computational infrastructures, direct control needs to be replaced by distributed coordination mechanisms that are on par with institutional constructs observable in human societies (contracts, agreements, enforcement mechanisms, etc.). This paper presents a formalization of Hohfeld's framework building upon a logic whose language includes primitive operators of ability and parametric deontic operators. The proposal is meant to highlight the fundamental interaction between deontic and (...) potestative concepts and contains proofs of soundness and completeness with respect to a class of relational models. (shrink)

How are we to understand the intentionality of desire? According to the two classical views, desire is either a positive evaluation or a disposition to act. This essay examines these conceptions of desire and argues for a deontic alternative, namely the view that desiring is representing a state of affairs as what ought to be. Three lines of criticism of the classical pictures of desire are provided. The first concerns desire’s direction of fit, i.e. the intuition that the world should (...) conform to our desires. The second concerns the “death of desire” principle, i.e. the intuition that one cannot desire what one represents as actual. The last pertains to desire’s role in psychological explanations, i.e. the intuition that desires can explain motivations and be explained by evaluations. Following these criticisms, three positive arguments in favor of the deontic conception are sketched. (shrink)

This chapter contains sections titled: Modal Concepts The Semantics of Modalities and Systems of Modal Logic Modality and Quantification Deontic, Epistemic, and Temporal Modalities Epistemic Logic Deontic Logic Temporal Frames Conditional Obligations and Rules of Detachment.

There are a number of concepts of common-sense morality, what one must do, what one ought to do, the supererogatory, the minimum that duty allows, the morally optional and the morally indifferent, that philosophers have been hard-pressed to represent in an integrated conceptual framework. Indeed, many philosophers have despaired at the attempt and concluded that only a fragment of these concepts belong to that fundamental sphere of morality that is the central focus of the ethicist. For example, the (...) traditional scheme, with its triad of the obligatory, the forbidden and the permissible, pigeonholes all actions into three mutually exclusive and exhaustive classes: those which are obligatory, those which are forbidden and those which are optional. Hence, at best, it can represent exactly two of the six aforementioned concepts. For from the standpoint of this scheme, what one must do and what one ought to do can't be distinguished and hence they can't both be represented. Although the morally optional can be represented, the supererogatory, one of its subclasses, cannot be represented. Furthermore, the morally indifferent, another subclass of the optional--one which is obviously disjoint from the supererogatory--cannot be represented. Finally, the minimum that duty allows finds no distinctive place in the traditional scheme. Thus, on the face of it, the traditional scheme is radically incomplete. ;I present, motivate and defend a new conceptual scheme for common-sense morality in which these concepts are represented and systematically integrated. An intuitively motivated semantic framework underpinning this conceptual scheme is also presented. Such a scheme, along with the associated semantic framework, is motivated by reflecting on the supererogationist's objections to utilitarianism and to the traditional scheme. But in addition, a new integrated network of linguistic motivations for this conceptual scheme is uncovered, one which is completely independent of supererogationistic considerations. Hence, these two separate sources of evidence for the centrality of this new scheme to our pre-theoretic thinking corroborate one another--thus jointly boosting the evidence beyond the mere sum of their separate evidential values. (shrink)

In this paper we present an executable approach to model interactions between agents that involve sensitive, privacy-related information. The approach is formal and based on deontic, epistemic and action logic. It is conceptually related to the Belief-Desire-Intention model of Bratman. Our approach uses the concept of sphere as developed by Waltzer to capture the notion that information is provided mostly with restrictions regarding its application. We use software agent technology to create an executable approach. Our agents hold beliefs about the (...) world, have goals and commitment to the goals. They have the capacity to reason about different courses of action, and communicate with one another. The main new ingredient of our approach is the idea to model information itself as an intentional agent whose main goal it is to preserve the integrity of the information and regulate its dissemination. We demonstrate our approach by applying it to an important process in the insurance industry: applying for a life insurance. In this paper we will: (1) describe the challenge organizational complexity poses in moral reasoning about informational relationships; (2) propose an executable approach, using software agents with reasoning capacities grounded in modal logic, in which moral constraints on informational relatio nships can be modeled and investigated; (3) describe the details of our approach, in which information itself is modeled as an intentional agent in its own right; (4) test and validate it by applying it to a concrete ‘hard case’ from the insurance industry; and (5) conclude that our approach upholds and offers potential for both research and practical application. (shrink)

Standard deontic logic (SDL) is defined on the basis of possible world semantics and is a logic of alethic-deontic modalities rather than deontic modalities alone. The interpretation of the concepts of obligation and permission comes down exclusively to the logical value that a sentence adopts for the accessible deontic alternatives. Here, we set forth a different approach, this being a logic which additionally takes into consideration whether sentences stand in relation to the normative system or to the system of (...) values under which we predicate the deontic qualifications. By taking this aspect into account, we arrive at a logical system which preserves laws proper to a deontic logic but where the standard paradoxes of deontic logic do not arise. It is a logic of strictly-deontic modalities DR. (shrink)

The biennial DEON conferences are designed to promote interdisciplinary cooperation amongst scholars interested in linking the formal-logical study of normative concepts and normative systems with computer science, artificial intelligence, linguistics, philosophy, organization theory and law. In addition to these general themes, DEON 2016 encouraged a special focus on the topic "Reasons, Argumentation and Justification.".

Deontic logic is the logic of normative concepts such as obligation, permission, and prohibition. This non-technical overview of the area has a strong emphasis on the connections between deontic logic and problems discussed in moral philosophy. Major issues treated are the distinction between ought-to-be and ought-to-do, the various meanings of permissive expressions, the logical relations among norms, the paradoxes of deontic logic, and the nature of moral conflicts and moral dilemmas. It is concluded that deontic logic has resources for (...) precise treatment of important issues in moral philosophy, but in order to make full use of these resources, more co-operation between logicians and moral philosophers is needed. (shrink)

In this paper, we indicate how Jan Woleński’s non-linguistic concept of the norm allows us to clarify the deontic relationship between sentences and the given normative system. A relationship of this kind constitutes a component of the metalogic of relating deontic logic, which subjects the logical value of the deontic sentence to the logical value of the constituent sentence and its relationship with a given normative system in the accessible possible worlds.

This paper suggests that it should be possible to develop dynamic deontic logic as a counterpart to the very successful development of dynamic doxastic logic (or dynamic epistemic logic, as it is more often called). The ambition, arrived at towards the end of the paper, is to give formal representations of agentive concepts such as “the agent is about to do (has just done) α ” as well as of deontic concepts such as “it is obligatory (permissible, forbidden) (...) for the agent to do α ”, where α stands for an action (event). (shrink)

Deontic logic is a branch of logic that investigates normative concepts, systems of norms and normative reasoning. The formal languages of deontic logic include normative concepts that correspond to natural language notions such as ought, obligatory, permissible, forbidden and optional. The present book is an introduction to this branch of logic. Several basic deontic systems are described and some of their properties are explored. Every system is characterized both semantically using possible world semantics and axiomatically. The final chapter (...) includes soundness and completeness results for every system. The focus of the study is formal, but some philosophical questions are also raised, in particular: What is the meaning of the word "ought" and other normative notions as they occur in ordinary and philosophical discussions? Several distinctions between different kinds of obligations are considered, for instance the distinctions between prima facie and all things considered obligations and between conditional and unconditional obligations. The book is aimed at people with no prior knowledge of deontic logic but with some acquaintance with classical logic including some set theory. It should interest anyone who wants to know more about this area. (shrink)

In this paper we present an executable approach to model interactions between agents that involve sensitive, privacy-related information. The approach is formal and based on deontic, epistemic and action logic. It is conceptually related to the Belief-Desire-Intention model of Bratman. Our approach uses the concept of sphere as developed by Waltzer to capture the notion that information is provided mostly with restrictions regarding its application. We use software agent technology to create an executable approach. Our agents hold beliefs about the (...) world, have goals and commitment to the goals. They have the capacity to reason about different courses of action, and communicate with one another. The main new ingredient of our approach is the idea to model information itself as an intentional agent whose main goal it is to preserve the integrity of the information and regulate its dissemination. We demonstrate our approach by applying it to an important process in the insurance industry: applying for a life insurance.In this paper we will: (1) describe the challenge organizational complexity poses in moral reasoning about informational relationships; (2) propose an executable approach, using software agents with reasoning capacities grounded in modal logic, in which moral constraints on informational relatio nships can be modeled and investigated; (3) describe the details of our approach, in which information itself is modeled as an intentional agent in its own right; (4) test and validate it by applying it to a concrete ‘hard case’ from the insurance industry; and (5) conclude that our approach upholds and offers potential for both research and practical application. (shrink)

Whereas geometrical oppositions (logical squares and hexagons) have been so far investigated in many fields of modal logic (both abstract and applied), the oppositional geometrical side of “deontic logic” (the logic of “obligatory”, “forbidden”, “permitted”, . . .) has rather been neglected. Besides the classical “deontic square” (the deontic counterpart of Aristotle’s “logical square”), some interesting attempts have nevertheless been made to deepen the geometrical investigation of the deontic oppositions: Kalinowski (La logique des normes, PUF, Paris, 1972) has proposed a (...) “deontic hexagon” as being the geometrical representation of standard deontic logic, whereas Joerden (jointly with Hruschka, in Archiv für Rechtsund Sozialphilosophie 73:1, 1987), McNamara (Mind 105:419, 1996) and Wessels (Die gute Samariterin. Zur Struktur der Supererogation, Walter de Gruyter, Berlin, 2002) have proposed some new “deontic polygons” for dealing with conservative extensions of standard deontic logic internalising the concept of “supererogation”. Since 2004 a new formal science of the geometrical oppositions inside logic has appeared, that is “ n -opposition theory”, or “NOT”, which relies on the notion of “logical bi-simplex of dimension m ” ( m = n − 1). This theory has received a complete mathematical foundation in 2008, and since then several extensions. In this paper, by using it, we show that in standard deontic logic there are in fact many more oppositional deontic figures than Kalinowski’s unique “hexagon of norms” (more ones, and more complex ones, geometrically speaking: “deontic squares”, “deontic hexagons”, “deontic cubes”, . . ., “deontic tetraicosahedra”, . . .): the real geometry of the oppositions between deontic modalities is composed by the aforementioned structures (squares, hexagons, cubes, . . ., tetraicosahedra and hyper-tetraicosahedra), whose complete mathematical closure happens in fact to be a “deontic 5-dimensional hyper-tetraicosahedron” (an oppositional very regular solid). (shrink)

Desires matter. How are we to understand the intentionality of desire? According to the two classical views, desire is either a positive evaluation or a disposition to act: to desire a state is to positively evaluate it or to be disposed to act to realize it. This Ph.D. Dissertation examines these conceptions of desire and proposes a deontic alternative inspired by Meinong. On this view, desiring is representing a state of affairs as what ought to be or, if one prefers, (...) as what should be. Desire involves a deontic manner of representing: a norm of the ought-to-be type features in desire’s intentional mode, as opposed to content. The dissertation is structured in three parts. In order to defend this conception, I formulate three main desiderata for a promising theory of the intentionality of desire in the introduction (§0). The first concerns desire’s direction of fit, i.e. the intuition that the world should conform to our desires. The second concerns the death of desire principle, i.e. the intuition that one cannot desire what one represents as actual. The last pertains to desire’s role in psychological explanations, i.e. the intuition that desires can explain some mental states and be explained by other mental states. The first part examines the main conceptions of desire in light of these desiderata. I argue that the classical pictures of desire do not adequately meet our desiderata. The first chapter is devoted to the evaluative conception (§1), while the second examines the motivational approach (§2). Following these criticisms, I then present the deontic view of desire (§3). In the second part, I defend this conception with the help of three arguments. The main idea is that appealing to norms of the ought-to-be type can satisfy our chief desiderata: the world should conform to norms (world-to-mind direction of fit, §4), norms are grounded on values and in turn ground obligations (explanation, §5), and norms are about non-actual states of affairs (death of desire principle, §6). In the last part, I develop the deontic view to draw a cartography of the various types of desire. Some desires are correct, while others are inappropriate. This distinction is explained by the deontic conception, as it matches that between states of affairs that ought to obtain and states that should not obtain (§7). Two study cases are examined: caprice and the impermissibility of desire aggregation. Intuitively, hopes, wishes, or urges are types of desire. The next chapter presents a typology inspired by the deontic view and the type of norms there are (§8). The last chapter discusses the main objections to the deontic approach (§9). In conclusion, I show the relevance of the deontic view for several debates in philosophy of mind and ethics. Desires are crucial because they are the ‘eye’ of what should be. (shrink)

The present volume is a sequel to Deontic Logic: Introductory and Systematic Readings : its purpose is to offer a view of some of the main directions of research in contemporary deontic logic. Most of the articles included in Introductory and Systematic Readings represent what may be called the standard modal approach to deontic logic, in which de on tic logic is treated as a branch of modal logic, and the normative concepts of obligation, permission and prohibition are regarded (...) as analogous to the "alethic" modalities necessity, possibility and impossibility. As Simo Knuuttila shows in his contribution to the present volume, this approach goes back to late medieval philosophy. Several 14th century philosophers observed the analogies between deontic and alethic modalities and discussed the deontic interpretations of various laws of modal logic. In contemporary deontic logic the modal approach was revived by G. H. von Wright's classic paper 'Deontic Logic'. Certain analogies between deontic and alethic modalities are obvious and uncontroversial, but the standard approach has often been criticized on the ground that it exaggerates the analogies and tends to ignore those features of normative concepts which distinguish them from other modalities. (shrink)

It is generally accepted that there are two kinds of normative concepts : evaluative concepts, such as good, and deontic concepts, such as ought. The question that is raised by this distinction is how it is possible to claim that evaluative concepts are normative. Given that deontic concepts appear to be at the heart of normativity, the bigger the gap between evaluative and deontic concepts, the less it appears plausible to say that evaluative (...) class='Hi'>concepts are normative. After having presented the main differences between evaluative and deontic concepts, and shown that there is more than a superficial difference between the two kinds, the paper turns to the question of the normativity of evaluative concepts. It will become clear that, even if these concepts have different functions, there are a great many ties between evaluative concepts, on the one hand, and the concepts of ought and of reason, on the other. (shrink)

This article analyzes the thesis of ethical relativism, as defended by Alchourrón and Bulygin. These authors offer, on the one hand, a suggestive conception according to which the question “what are our obligations?” is equivalent to thinking about what is to be done; on the other hand, they defend a relativist conception of ethics. They present three objections to constructivist accounts of ethics that are not relativist: a) the argument of the burden of the proof; b) a version of the (...) dilemma of Euthyphro, and c) the argument of particularism. This article presents counterarguments to these objections in the attempt to show that they are not conclusive and that a space therefore remains for objectivity in the normative sphere. Keywords: Alchourrón-Bulygin, ethical relativism, ethical constructivism, burden of proof, particularism. (shrink)

In this paper, I will discuss boulesic and deontic logic and the relationship between these branches of logic. By ‘boulesic logic,’ or ‘the logic of the will,’ I mean a new kind of logic that deals with ‘boulesic’ concepts, expressions, sentences, arguments and systems. I will concentrate on two types of boulesic expression: ‘individual x wants it to be the case that’ and ‘individual x accepts that it is the case that.’ These expressions will be symbolised by two sentential (...) operators that take individuals and sentences as arguments and give sentences as values. Deontic logic is a relatively well-established branch of logic. It deals with normative concepts, sentences, arguments and systems. In this paper, I will show how deontic logic can be grounded in boulesic logic. I will develop a set of semantic tableau systems that include boulesic and alethic operators, possibilist quantifiers and the identity predicate; I will then show how these systems can be augmented by a set of deontic operators. I use a kind of possible world semantics to explain the intended meaning of our formal systems. Intuitively, we can think of our semantics as a description of the structure of a perfectly rational will. I mention some interesting theorems that can be proved in our systems, including some versions of the so-called hypothetical imperative. Finally, I show that all systems that are described in this paper are sound and complete with respect to their semantics. (shrink)

The paper discusses ten philosophical problems in deontic logic: how to formally represent norms, when a set of norms may be termed ‘coherent’, how to deal with normative conflicts, how contraryto-duty obligations can be appropriately modeled, how dyadic deontic operators may be redefined to relate to sets of norms instead of preference relations between possible worlds, how various concepts of permission can be accommodated, how meaning postulates and counts-as conditionals can be taken into account, and how sets of norms (...) may be revised and merged. The problems are discussed from the viewpoint of input/output logic as developed by van der Torre & Makinson. We argue that norms, not ideality, should take the central position in deontic semantics, and that a semantics that represents norms, as input/output logic does, provides helpful tools for analyzing, clarifying and solving the problems of deontic logic. (shrink)

This multiplex semantics incorporates multiple relations of deontic accessibility or multiple preference rankings on alternative worlds to represent distinct normative standards. This provides a convenient framework for deontic logic that allows conflicts of obligation, due either to conflicts between normative standards or to incoherence within a single standard. With the multiplex structures, two general senses of "ought" may be distinguished, an indefinite sense under which something is obligatory when it is enjoined by some normative standard and a core sense for (...) when something is enjoined by all normative standards. Multiple normative standards may themselves be given a preferential order; this leads to a concept of ranked obligation. This paper presents the foundations of this multiplex semantics and the propositional deontic logics they define. (shrink)

We present axiomatizations of the deontic fragment of Anderson's relevant deontic logic (the logic of obligation and related concepts) and the eubouliatic fragment of Anderson's eubouliatic logic (the logic of prudence, safety, risk, and related concepts).

The ‘deontic orientation’ thesis—that is, the claim that ancient Indian legal theory is orientated or focussed towards duty to the exclusion of other jural operators—features prominently in the discourse of ancient Indian law. In contrast, contemporary legal systems tend to employ a variety of other jural operators also, including right, liberty, power, and so forth. Theorists like Wesley Hohfeld even assert that these operators are elemental, and hence not reducible to other operators. This disparity may be addressed from various evaluational (...) and conceptual standpoints. I address instead a more basic question: is the disparity real? Does a scrutiny of legal treatises factually validate the deontic orientation thesis? I contend that the thesis is factually not sustainable, and that legal treatises of ancient India do display a sophisticated conception of non-deontic operators. To this end I undertake a scrutiny of Kauṭilya’s Arthaśāstra, to determine the treatise’s use of non-deontic operators, and whether it treats them as entities in their own standing as opposed to derivatives or outcomes of the deontic. (shrink)

Abstract.The authors concentrate on the analysis of the concept of permission. After a general account of differing concepts of permission both with regard to different legal theories and to different legal ideologies, they argue in favour of a “radical” imperativism which leaves no place for permissive norms. Thus, in contrast with the logic of normative language (LNL) purported by Alchourrón and Bulygin, the authors figure out a system of deontic logic ‐ supplemented by devices of the possible world semantics (...) ‐ according to which a normative system (N) is conceived as a set of logical consequences of a certain finite set of basic obligations and no room is left either for the concept of weak permission or for the concept of strong permission. Finally the authors raise some criticisms concerning the view maintained by Alchourron and Bulygin on strong permission.*. (shrink)

Philosophical debate about the meaning of normative terms has long been pulled in two directions by the apparently competing ideas: (i) ‘ought’s do not describe what is actually the case but rather prescribe possible action, thought, or feeling, (ii) all declarative sentences deserve the same general semantic treatment, e.g. in terms of compositionally specified truth conditions. In this paper, I pursue resolution of this tension by rehearsing the case for a relatively standard truth-conditionalist semantics for ‘ought’ conceived as a necessity (...) modal and proposing a revision to it motivated by the distinctively prescriptive character of some deontic modals. In my view, this puts pressure on a popular conception of one of the core debates of metanormative theory between realists and antirealists. To make good on this claim, I go on to explore two very general ways we might interpret the results of compositional semantics—“representationalism” and “inferentialism”—in order to argue that, contrary to what is generally assumed, both can capture the special prescriptivity of ‘ought’ and both can countenance compositionally specified and informative truth-conditions for ought-sentences. Hence, my main thesis is that the deciding factor between them should not be which of ideas (i) and (ii) we are more impressed by but rather what we think of the relative merits of how representationalism and inferentialism respect these ideas. I’m inclined to favor an antirealist form of inferentialism, but the task I’ve set myself here is mainly to articulate the view in the context of metanormative theory and the semantics of deontic modals rather than try to defend it fully. To this purpose, towards the end I also briefly compare and contrast inferentialism with a third “ideationalist” metasemantic view, which may be an attractive home for some sophisticated versions of metanormative expressivism. Depending on how expressivism is worked out, it may be completely compatible with and so perhaps usefully combined with inferentialism or it may offer a competing way to respect ideas (i) and (ii). (shrink)

This paper outlines a semantic account of attitude reports and deontic modals based on cognitive and illocutionary products, mental states, and modal products, as opposed to the notion of an abstract proposition or a cognitive act.

This chapter offers a concise and elementary introduction to fundamental concepts in deductive and deontic reasoning.

Many medieval philosophers and logicians regarded modal logic as a model for epistemic, normative and optative concepts on the basis of their apparent similarities to modal concepts. These interpretations of modal logic led to critical studies of the applicability of modal principles to deontic concepts. Some philosophers presented apparent counterexamples to the deontic interpretation of the Consequence Principle, according to which the consequences of what is obligatory (or permitted) are also obligatory (permitted). These examples are variants of (...) Lennart Åqvist's paradox of the Good Samaritan. In this article it is argued that the examples involve a confusion between the compounded and the divided senses of deontic propositions, and are not genuine counterexamples to the Consequence Principle. If the concept of knowledge is analysed as epistemically satisfactory belief, the paradox of epistemic obligation can be solved in a similar way. (shrink)

The principal aim of this book is to develop and defend an analysis of the concept of moral obligation. The analysis is neutral regarding competing substantive theories of obligation, whether consequentialist or deontological in character. What it seeks to do is generate solutions to a range of philosophical problems concerning obligation and its application. Amongst these problems are deontic paradoxes, the supersession of obligation, conditional obligation, prima facie obligation, actualism and possibilism, dilemmas, supererogation, and cooperation. By virtue of its normative (...) neutrality, the analysis provides a theoretical framework within which competing theories of obligation can be developed and assessed. This study is a major contribution to metaethics that will be of particular interest to all philosophers concerned with normative ethical theory. (shrink)

Seventeenth century philosopher Gottfried Leibniz's contributions to metaphysics, mathematics, and logic are well known. Lesser known is his ‘invention’ of deontic logic, and that his invention derives from the alethic logic of the Aristotelian square of opposition. In this paper, I show how Leibniz developed this ‘logic of duties’, which designates actions as ‘possible, necessary, impossible, and omissible’ for a ‘vir bonus’ . I show that for Leibniz, deontic logic can determine whether a given action, e.g. as permitted, is therefore (...) obligatory or prohibited . Secondly, since the deontic modes are derived from what is possible, necessary, etc., for a good person to do, and that ‘right and obligation’ are the ‘moral qualities’ of a good person, we can see how Leibniz derives deontic logic from these moral qualities. Finally, I show how Leibniz grounds a central deontic concept, namely obligation, in the human capacity for freedom. (shrink)