A Kelsenian Deontic Logic

Mapping Intimacies ◽

10.3233/faia210330 ◽

2021 ◽

Author(s):

Agata Ciabattoni ◽

Xavier Parent ◽

Giovanni Sartor

Keyword(s):

Deontic Logic ◽

Deontic Paradoxes

Inspired by Kelsen’s view that norms establish causal-like connections between facts and sanctions, we develop a deontic logic in which a proposition is obligatory iff its complement causes a violation. We provide a logic for normative causality, define non-contextual and contextual notions of illicit and duty, and show that the logic of such duties is well-behaved and solves the main deontic paradoxes.

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The Robbery Paradox

Dialogue ◽

10.1017/s001221730004659x ◽

1983 ◽

Vol 22 (3) ◽

pp. 433-440

Author(s):

Mark Vorobej

Keyword(s):

Deontic Logic ◽

Critical Discussion ◽

Conditional Obligation ◽

Proper Formulation ◽

Deontic Paradoxes

James E. Tomberlin [6] has recently argued that the logical systems of conditional obligation proposed by Azizah al-Hibri [1] and Peter Mott [5] are incapable of resolving at least one variant of the notorious contrary to duty imperative paradox, formulated originally by Chisholm [2]. Tomberlin concedes that these systems offer the very best of the' “conditional obligation approach” to deontic logic and concludes his critical discussion with the pessimistic remark that “the best of this approach is simply not good enough. Deontic logic … is obliged to turn elsewhere for its proper formulation and resolution of the deontic paradoxes” ([6], 373). Below I argue that Tomberlin's three central arguments against al-Hibri and Mott are fallacious.

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Deontic Paradoxes and Tableau System for Kalinowski’s Deontic Logic K1

Bulletin of the Section of Logic ◽

10.18778/0138-0680.46.3.4.07 ◽

2017 ◽

Vol 46 (3/4) ◽

Author(s):

Janusz Ciuciura

Keyword(s):

Deontic Logic ◽

Formal System ◽

Tableau System ◽

Deontic Paradoxes

In 1953, Jerzy Kalinowski published his paper on the logic of normative sentences. The paper is recognized as one of the first publications on the formal system of deontic logic. The aim of this paper is to present a tableau system for Kalinowski’s deontic logic and to discuss some of the topics related to the paradoxes of deontic logic.

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Defeasibility applied to Forrester’s paradox

South African Computer Journal ◽

10.18489/sacj.v32i2.848 ◽

2020 ◽

Vol 32 (2) ◽

Author(s):

Julian Chingoma ◽

Thomas Meyer

Keyword(s):

Deontic Logic ◽

Defeasible Reasoning ◽

Logic Systems ◽

Legal Domain ◽

Deontic Paradoxes ◽

Logic System

Deontic logic is a logic often used to formalise scenarios in the legal domain. Within the legal domain there are many exceptions and conflicting obligations. This motivates the enrichment of deontic logic with not only the notion of defeasibility, which allows for reasoning about exceptions, but a stronger notion of typicality that is based on defeasibility. KLM-style defeasible reasoning is a logic system that employs defeasibility while Propositional Typicality Logic (PTL) is a logic that does the same for the notion of typicality. Deontic paradoxes are often used to examine logic systems as the paradoxes provide undesirable results even if the scenarios seem intuitive. Forrester’s paradox is one of the most famous of these paradoxes. This paper shows that KLM-style defeasible reasoning and PTL can be used to represent and reason with Forrester’s paradox in such a way as to block undesirable conclusions without completely sacrificing desirable deontic properties.

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Dyadic Obligations over Complex Actions as Deontic Constraints in the Situation Calculus

Proceedings of the Seventeenth International Conference on Principles of Knowledge Representation and Reasoning ◽

10.24963/kr.2020/26 ◽

2020 ◽

Author(s):

Jens Claßen ◽

James Delgrande

Keyword(s):

Artificial Intelligence ◽

Deontic Logic ◽

Action Theory ◽

Prima Facie ◽

Situation Calculus ◽

Artificial Agents ◽

Planning Techniques ◽

Course Of Action ◽

Reasoning About Action ◽

The Given

With the advent of artificial agents in everyday life, it is important that these agents are guided by social norms and moral guidelines. Notions of obligation, permission, and the like have traditionally been studied in the field of Deontic Logic, where deontic assertions generally refer to what an agent should or should not do; that is they refer to actions. In Artificial Intelligence, the Situation Calculus is (arguably) the best known and most studied formalism for reasoning about action and change. In this paper, we integrate these two areas by incorporating deontic notions into Situation Calculus theories. We do this by considering deontic assertions as constraints, expressed as a set of conditionals, which apply to complex actions expressed as GOLOG programs. These constraints induce a ranking of "ideality" over possible future situations. This ranking in turn is used to guide an agent in its planning deliberation, towards a course of action that adheres best to the deontic constraints. We present a formalization that includes a wide class of (dyadic) deontic assertions, lets us distinguish prima facie from all-things-considered obligations, and particularly addresses contrary-to-duty scenarios. We furthermore present results on compiling the deontic constraints directly into the Situation Calculus action theory, so as to obtain an agent that respects the given norms, but works solely based on the standard reasoning and planning techniques.

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