Defeasible Deontic Logic

En este trabajo analizo una nocion de consecuencia 16gica falible que represento en el metalenguaje con el signo " en particular reviso la nocion que creo adecuada para los razonamientos que operan con "normas derrotables" (ciertos condicionales no monotonicos que expreso en el lenguaje objeto con la forma "A>B"). Sostengo que para dar cuenta de las inferencias basadas en normas derrotables debe apelarse a una nocion de consecuencia logica no deductiva que tiene analogias con la nocion de condicional derrotable (CO), pero tambien diferencias importantes. En particular, la noci6n de consecuencia 16gica falible cumple, a diferencia de los CD, con el principio de monotonia cauta, asi como con el de que un conjunto de premisas consistente no puede arrojar conclusiones contradictorias. Por tiltimo, sostengo que todo CD encubre uno estricto en el sentido de que, para todo par de formulas <A,B>, el CD A>B equivale a un condicional estricto /[A,B)->B. (Llamo a/(x,y) "funcion de selecci6n".) Afirmo analogamente que para cada razonamiento falible R hay un razonamiento paralelo R' que implica deductivamente a la conclusidn de R, pero en este caso la funcion de selection que identifica las premisas de R' no depende de premisas y conclusion, sino unicamente del conjunto de las premisas. Asi, recupero para la noci6n de consecuencia 16gica derrotable propiedades que son frecuentemente atribuidas a nociones de consecuencia derrotables y que yo rechazo para los condicionales mientras las mantengo para la noci6n de consecuencia que opera sobre aquellos. Finalmente, rechazo para la relacidn de inferencia derrotable un principio importante del que carece la 16gica de los CD pero que es usualmente aceptado para la inferencia derrotable, el principio de corte cauto. Asi, acepto una nocion de consecuencia derrotable menos permisiva que otras estandar pero a la vez mas segura. T£rminos clave: consecuencia 16gica, condicional derrotable, consecuencia falible.

We introduce the DR-CONTRACT architecture to represent and reason on e-Contracts. The architecture extends the DR-device architecture by a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe e-contracts for a monitoring perspective in Defeasible Logic.

In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe econtracts for a monitoring perspective in Defeasible Logic.

4 EI sistema que propuse en [Pazos 2002] (ver nota 1) y que reproduzco parcialmente aqui es una modification del de Alchourron en [Alchourron, 1996], C. A. Alchourron, "Defeasible Logics: Demarcation and Affinities" en G Crocco, L. Farinas del Cerro y A. Herzig (Comps.

In this paper we introduce a prioritized default logic. We build this logic modularly from Standard Deontic Logic by the addition of default rules and priorities among them. Our main aim is to provide a logical framework to reason about scenarios where prescriptive and descriptive statements coexist and may be incomplete and contradictory. We motivate and illustrate the technical elements of our work with the use of examples (classical, and coming from software engineering). In addition, we present sound, complete, and terminating (with loop check) tableau-based proof calculi for credulous and sceptical reasoning in our logic.

In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe econtracts for a monitoring perspective in Defeasible Logic.

This thesis belongs to the field of Fuzzy Logic and focuses on some significant matters related to the problem of aggregating information in a fuzzy environment. First of all, one of the most important issues in ftizzy logic theory is approached: the problem of how to extend to the fuzzy world the classical intersection and unión set operations. Although the well-known triangular norm and conorm operators, due both to their mathematical properties and their great variety, provide an excellent model, these operators are very often used as a matter of routine, even in situations where some of their properties-such as commutativity or associativity-are not required and therefore become an unnecessary restriction. This work proposes (chapter 2) a new mathematical model for fuzzy conjunctions and disjunctions that, in addition of being a generalisation of the classical model, includes the most relevant models suggested to date and provides an enlarged class of operators. 5-25 Familia de operadores mixtos idempotentes (secciones) 5-26 Familia de operadores mixtos (secciones) Capítulo 1 INTRODUCCIÓN El presente trabajo pretende ser una contribución al desarrollo de un amplio campo de investigación que se enmarca dentro de la lógica borrosa y que estudia el problema de cómo agregar información cuando ésta es incompleta, imprecisa y/o incierta y sus diversas aplicaciones. Este capítulo se ha estructurado de la siguiente forma: El primer apartado se dedica a introducir de forma general el problema de la agregación de información y a comentar con más detalle el tratamiento de esta cuestión cuando la información de la que se parte, al ser vaga e imprecisa, se formaliza por medio de subconjuntos borrosos. El apartado 1.2 expone ios objetivos concretos que, dentro del campo anterior, se persiguen en este trabajo y las ideas que los han motivado. Presenta además para cada uno de ellos una breve reseña de los trabajos previos más significativos, haciendo especial hincapié en aquéllos que aquí han sido utiüzados como punto de partida básico. Por último, el apartado 1.3 esboza las líneas generales del contenido de la tesis y la forma en que ésta se organiza, mientras que el apartado 1.4 incluye la notación específica utilizada a lo largo de todo el trabajo.

This paper examines how a notion of stable explanation developed elsewhere in Defeasible Logic can be expressed in the context of formal argumentation. With this done, we discuss the deontic meaning of this reconstruction and show how to build from argumentation neighborhood structures for deontic logic where this notion of explanation can be characterised. Some direct complexity results are offered.

Free Choice Permission is one of the challenges for the formalisation of norms. In this paper, we follow a novel approach that accepts Free Choice Permission in a restricted form. The intuition behind the guarded form is strongly aligned with the idea of defeasibility. Accordingly, we investigate how to model the guarded form in Defeasible Deontic Logic extended with disjunctive permissions.

The ESSLLI course material has been compiled by Leon van der Torre and Jörg Hansen. Unless otherwise mentioned, the copyright lies with the individual authors of the material. Leon van der Torre and Jörg Hansen declare that they have obtained all necessary permissions for the distribution of this material. ESSLLI 2008 and its organizers take no legal responsibility for the contents of this booklet.

I t is not a coincidence that the research fields of artificial intelligence and of law have met and have merged into the interdisciplinary research field of artificial intelligence and law. Both fields use formal methods, with their strengths and limitations; in AI there are software, logic, and statistics, in law there are statutes, procedures, and institutions. Both fields are creative; in AI, systems are built, experiments designed, and paradigms replaced; in law, regulations are passed by lawmakers, precedents are set, and ideologies balanced. Both fields struggle with the inevitable complexity of modeling human behavior-in AI with the goal to reconstruct human behavior, in law with the goal to steer human behavior. These and other similarities are driving the active and dedicated community of AI and law. Researchers are taking their inspiration from the law with its insights developed over millennia combining them with AI's half a century of lessons. The beginnings of AI and law are marked by the

Cracking the Code: Rulemaking for Humans and Machines is an OECD Working Paper authored&lt;br&gt; by James Mohun and Alex Roberts and released on 14 October 2020. This Working Paper on&lt;br&gt; Public Governance, produced by the OECD Observatory of Public Sector Innovation, is available&lt;br&gt; in English and French. A draft version was publicly available on the web for comments. In August&lt;br&gt; 2020 the La Trobe LawTech team reached out to the authors and provided some comments on the&lt;br&gt; draft Working Paper. Rules as Code is gaining momentum, increasing the need for constructive&lt;br&gt; critical engagement. To support the broader discussions around Rules as Code, we are publishing&lt;br&gt; our August 2020 Comments. These are provided in their original form, with small technical and&lt;br&gt; language edits for wider publication.

In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe econtracts for a monitoring perspective in Defeasible Logic.

P al au, Gl ad ys (et al i i). Lóg i c as c ond i c i onal e s y r az onami e nt o d e se nt i d o c omún. Bar c e l ona, Ge d i sa, 2004, p p. 190. P or M ar í a I né s C or b al án y Fe d e r ic o E. Lóp e z UNLP Tal como lo indica su título, la compilación está dedicada al estudio de las lógicas condicionales y del razonamiento de sentido común. Una de las características

Un modelo múltiple para la ponderación propone una metodología para resolver conflictos entre principios jurídicos, en la línea de Robert Alexy, en el sentido de que entiende los principios como máximas de optimización, pero diferente. Implica también una fuerte crítica a Alexy y a los llamados modelos diádicos y propone un modelo múltiple, que muestra que hay muchas más alternativas que las que los modelos tradicionales ven, en los casos de ponderación jurídica.

This paper analyses and compares some of the automated reasoners that have been used in recent research for compliance checking. Although the list of the considered reasoners is not exhaustive, we believe that our analysis is representative enough to take stock of the current state of the art in the topic. We are interested here in formalizations at the first-order level. Past literature on normative reasoning mostly focuses on the propositional level. However, the propositional level is of little usefulness for concrete LegalTech applications, in which compliance checking must be enforced on (large) sets of individuals. Furthermore, we are interested in technologies that are freely available and that can be further investigated and compared by the scientific community. In other words, this paper does not consider technologies only employed in industry and/or whose source code is non-accessible. This paper formalizes a selected use case in the considered reasoners and compares the i...

Está autorizada la reproducción total o parcial de este material siempre y cuando se cite la fuente. RESUMEN La Negación Clásica prohibe la compatibilidad de un enunciado con su negación y las indeterminaciones respecto a la negación. El sistema presentado en este trabajo, es una generalización de la Lógica Clásica. En él se tiene un operador Ilamado Negación Débil, el cual tiene la característica de no prohibir la compatibilidad de un enunciado con su negación ni las indeterminaciones respecto a la negación.

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Default logics represent an important class of the nonmonotonic formalisms. Using simple by powerful inference rules, called defaults, these logic systems model reasoning patterns of the form &quot;in the absence of infor- mation to the contrary of...&quot;, and thus formalize the default reasoning, a special type of nonmonotonic reasoning. In this paper we propose an auto- mated system, called DARR, with two components: a propositional theorem prover and a theorem prover for constrained and rational propositional default logics. A modified version of semantic tableaux method is used to implement the propositional prover. Also, this theorem proving method is adapted for computing extensions because one of its purpose is to produce models, and extensions are models of the world described by default theories.

In this paper we introduce a prioritized default logic. We build this logic modularly from Standard Deontic Logic by the addition of default rules and priorities among them. Our main aim is to provide a logical framework to reason about scenarios where prescriptive and descriptive statements coexist and may be incomplete and contradictory. We motivate and illustrate the technical elements of our work with the use of examples (classical, and coming from software engineering). In addition, we present sound, complete, and terminating (with loop check) tableau-based proof calculi for credulous and sceptical reasoning in our logic.

This article proposes a general strategy to overcome normative conflicts, namely, paradoxes represented in Standard Deontic Logic. This solution is based on preference relations between norms that circumvent situations of conflict. Pragmatic justifications of the proposed method are also given.

La colección Filosofía y Derecho publica aquellos trabajos que han superado una evaluación anónima realizada por especialistas en la materia, con arreglo a los estándares usuales en la comunidad académica internacional. Los autores interesados en publicar en esta colección deberán enviar sus manuscritos en documento Word a la dirección de correo electrónico manuscritos@filosofiayderecho.. Los datos personales del autor deben ser aportados en documento aparte y el manuscrito no debe contener ninguna referencia, directa o indirecta, que permita identificar al auto. En caso de ser aceptada la publicación del original, el autor deberá adaptarlo a los criterios de la colección, los cuales se pueden encontrar, en formato PDF, en la página web www.filosofiayrecho.es. Quedan rigurosamente prohibidas, sin la autorización escrita de los titulares del «Copyright», bajo las sanciones establecidas en las leyes, la reproducción total o parcial de esta obra por cualquier medio o procedimiento, comprendidos la reprografía y el tratamiento informático, y la distribución de ejemplares de ella mediante alquiler o préstamo públicos.

In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe econtracts for a monitoring perspective in Defeasible Logic.

Cracking the Code: Rulemaking for Humans and Machines is an OECD Working Paper authored&lt;br&gt; by James Mohun and Alex Roberts and released on 14 October 2020. This Working Paper on&lt;br&gt; Public Governance, produced by the OECD Observatory of Public Sector Innovation, is available&lt;br&gt; in English and French. A draft version was publicly available on the web for comments. In August&lt;br&gt; 2020 the La Trobe LawTech team reached out to the authors and provided some comments on the&lt;br&gt; draft Working Paper. Rules as Code is gaining momentum, increasing the need for constructive&lt;br&gt; critical engagement. To support the broader discussions around Rules as Code, we are publishing&lt;br&gt; our August 2020 Comments. These are provided in their original form, with small technical and&lt;br&gt; language edits for wider publication.

Knowledge representation and reasoning in the legal domain has primarily focused on case studies where knowledge and data can fit in main memory. However, this assumption no longer applies in the era of big data, where large amounts of data are generated daily. This paper discusses new opportunities and challenges that emerge in relation to reasoning with legal big data and the concepts of volume, velocity, variety and veracity. A four-layer legal big data framework is proposed to manage the complete lifecycle of legal big data from sourcing, processing and storage, to reasoning, analysis and consumption. Within each layer, a number of relevant future research directions are also identified, which can facilitate the realisation of knowledge-rich legal big data solutions.

© 2020 CEUR-WS. All rights reserved. We advance an alternative version of the Chisholm Paradox and we argue that the alternative version (while logically equivalent to the original version), in its manifestation in the natural language, is not intuitively consistent. The alternative version of the paradox suggests some requirements for deontic logics designed for legal reasoning.

In order to properly model norm change in the law, temporal aspects of legal dynamics must be considered. Since there exist several time-based features of law that should be studied, we discuss two interesting approaches: one based on defeasible logic and the other based on belief revision. Each of these makes use of one of the two classic forms of reasoning about time: point-based and interval-based. Both formalisms provide the necessary logical infrastructure to address the characterization of complex behaviour of legal dynamics.

© 2020 CEUR-WS. All rights reserved. We advance an alternative version of the Chisholm Paradox and we argue that the alternative version (while logically equivalent to the original version), in its manifestation in the natural language, is not intuitively consistent. The alternative version of the paradox suggests some requirements for deontic logics designed for legal reasoning.

The goal of the present research is to define a Semantic Web framework for precedent modelling, by using knowledge extracted from text, metadata, and rules, while maintaining a strong text-to-knowledge morphism between legal text and legal concepts, in order to fill the gap between legal document and its semantics. The framework is composed of four different models that make use of standard languages from the Semantic Web stack of technologies: a document metadata structure, modelling the main parts of a judgement, and creating a bridge between a text and its semantic annotations of legal concepts; a legal core ontology, modelling abstract legal concepts and institutions contained in a rule of law; a legal domain ontology, modelling the main legal concepts in a specific domain concerned by case-law; an argumentation system, modelling the structure of argumentation. The input to the framework includes metadata associated with judicial concepts, and an ontology library representing th...

This research aims to define an integrated methodology for modelling judgments, starting from legal texts and capturing not only structural parts but also arguments used by judges to reach conclusions. The goal is to build a complete ontology framework capable of detecting and modelling knowledge from the judgement’s text. The formalized judgements provide the necessary metadata for the rule layer to enable argumentation towards the acceptance or rejection of a given interpretation. For pursuing this goal it is important to integrate the legal ontology construction with a rule formalization following legal reasoning-oriented theory and defeasible logics, just like the Carneades application (presented here) follows Walton&#39;s argumentation theory. The XML interchange uses OWL, RuleML, and the emerging LegalRuleML.

In this paper we present an architecture to represent and reason on e-Contracts based on the DR-device architecture supplemented with a deontic defeasible logic of violation. We motivate the choice for the logic and we show how to extend RuleML to capture the notions relevant to describe econtracts for a monitoring perspective in Defeasible Logic.

Free Choice Permission is one of the challenges for the formalisation of norms. In this paper, we follow a novel approach that accepts Free Choice Permission in a restricted form. The intuition behind the guarded form is strongly aligned with the idea of defeasibility. Accordingly, we investigate how to model the guarded form in Defeasible Deontic Logic extended with disjunctive permissions.

Cracking the Code: Rulemaking for Humans and Machines is an OECD Working Paper authored&lt;br&gt; by James Mohun and Alex Roberts and released on 14 October 2020. This Working Paper on&lt;br&gt; Public Governance, produced by the OECD Observatory of Public Sector Innovation, is available&lt;br&gt; in English and French. A draft version was publicly available on the web for comments. In August&lt;br&gt; 2020 the La Trobe LawTech team reached out to the authors and provided some comments on the&lt;br&gt; draft Working Paper. Rules as Code is gaining momentum, increasing the need for constructive&lt;br&gt; critical engagement. To support the broader discussions around Rules as Code, we are publishing&lt;br&gt; our August 2020 Comments. These are provided in their original form, with small technical and&lt;br&gt; language edits for wider publication.

Traditionally, computational knowledge representation and reasoning focused its attention on rich domains such as the law. The main underlying assumption of traditional legal knowledge representation and reasoning is that knowledge and data are both available in main memory. However, in the era of big data, where large amounts of data are generated daily, an increasing range of scientific disciplines, as well as business and human activities, are becoming data-driven. This chapter summarises existing research on legal representation and reasoning in order to uncover technical challenges associated both with the integration of rules and databases and with the main concepts of the big data landscape. We expect these challenges lead naturally to future research directions towards achieving large scale legal reasoning with rules and databases.

In the past few years several business process compliance frameworks based on temporal logic have been proposed. In this paper we investigate whether the use of temporal logic is suitable for the task at hand: namely to check whether the speci cations of a business process are compatible with the formalisation of the norms regulating the business process. We provide an example inspired by real life norms where the use of linear temporal logic produces a result that is not compatible with the legal understanding of the norms in the example.

En este trabajo analizo una nocion de consecuencia 16gica falible que represento en el metalenguaje con el signo " en particular reviso la nocion que creo adecuada para los razonamientos que operan con "normas derrotables" (ciertos condicionales no monotonicos que expreso en el lenguaje objeto con la forma "A>B"). Sostengo que para dar cuenta de las inferencias basadas en normas derrotables debe apelarse a una nocion de consecuencia logica no deductiva que tiene analogias con la nocion de condicional derrotable (CO), pero tambien diferencias importantes. En particular, la noci6n de consecuencia 16gica falible cumple, a diferencia de los CD, con el principio de monotonia cauta, asi como con el de que un conjunto de premisas consistente no puede arrojar conclusiones contradictorias. Por tiltimo, sostengo que todo CD encubre uno estricto en el sentido de que, para todo par de formulas <A,B>, el CD A>B equivale a un condicional estricto /[A,B)->B. (Llamo a/(x,y) "funcion de selecci6n".) Afirmo analogamente que para cada razonamiento falible R hay un razonamiento paralelo R' que implica deductivamente a la conclusidn de R, pero en este caso la funcion de selection que identifica las premisas de R' no depende de premisas y conclusion, sino unicamente del conjunto de las premisas. Asi, recupero para la noci6n de consecuencia 16gica derrotable propiedades que son frecuentemente atribuidas a nociones de consecuencia derrotables y que yo rechazo para los condicionales mientras las mantengo para la noci6n de consecuencia que opera sobre aquellos. Finalmente, rechazo para la relacidn de inferencia derrotable un principio importante del que carece la 16gica de los CD pero que es usualmente aceptado para la inferencia derrotable, el principio de corte cauto. Asi, acepto una nocion de consecuencia derrotable menos permisiva que otras estandar pero a la vez mas segura. T£rminos clave: consecuencia 16gica, condicional derrotable, consecuencia falible.

Es habitual en la literatura de la legalidad distinguir entre enunciados "de tipo legal" (lawlike statements) como, por ejemplo, "Todos los metales se dilatan con el calor" y "generalizaciones accidentales", tales como "Todas las manzanas de esta cesta son rojas". Uno de los criterios de distincidn que se sugiere es aquel segun el cual los enunciados de forma legal, y no las generalizaciones accidentales, apoyan enunciados contrafacticos. La noci6n de "enunciado contrafictico" ha sido bastante trabajada 1. En cambio, la de "apoyo", bajo el supuesto de que apoyar un contrafictico es algo as! como "implicarlo", ha sido pricticamente olvidada, a pesar de que presenta algunas dificultades formales. A continuaci6n me extender^en una clarificacion de esta noci6n. En particular, me dedicare a clarificar en qu6 sentido apoyan contrafacticos enunciados de cierta clase, a saber, enunciados falibles de tipo legal. Respecto de ellos, equiparar la idea de "apoyo" a una suerte de "implication" supone algunas dificultades adicionales. Resolverlas es parte necesaria de cualquier propuesta que quisiera sostener a la vez que 1) existen enunciados de ley falibles y que 2) la afirmaci<5n de que los enunciados de ley, a diferencia de las generalizaciones accidentales, apoyan contrafacticos, constituye un Criterio aceptable de distinci6n entre ambos. Sin embargo, la elucidaci6n de estos conceptos es s61o un paso previo para el planteamiento del verdadero problema epistemoldgico de defender la segunda de las tesis indicadas. Terminos clave: contrafacticos, generalizaciones accidentales, ley falible.

Resumen: En este trabajo analizo una nocion de consecuencia 16gica falible que represento en el metalenguaje con el signo &quot; en particular reviso la nocion que creo adecuada para los razonamientos que operan con &quot;normas derrotables&quot; (ciertos condicionales no monotonicos que expreso en el lenguaje objeto con la forma &quot;A&gt;B&quot;). Sostengo que para dar cuenta de las inferencias basadas en normas derrotables debe apelarse a una nocion de consecuencia logica no deductiva que tiene analogias con la nocion de condicional derrotable (CO), pero tambien diferencias importantes. En particular, la noci6n de consecuencia 16gica falible cumple, a diferencia de los CD, con el principio de monotonia cauta, asi como con el de que un conjunto de premisas consistente no puede arrojar conclusiones contradictorias. Por tiltimo, sostengo que todo CD encubre uno estricto en el sentido de que, para todo par de formulas , el CD A&gt;B equivale a un condicional estricto /[A,B)-&gt;B. (...

Abstract. Default logics represent an important class of the nonmonotonic formalisms. Using simple by powerful inference rules, called defaults, these logic systems model reasoning patterns of the form ”in the absence of information to the contrary of... ”, and thus formalize the default reasoning, a special type of nonmonotonic reasoning. In this paper we propose an automated system, called DARR, with two components: a propositional theorem prover and a theorem prover for constrained and rational propositional default logics. A modified version of semantic tableaux method is used to implement the propositional prover. Also, this theorem proving method is adapted for computing extensions because one of its purpose is to produce models, and extensions are models of the world described by default theories. 1.

Abstract. In this paper we extend the logic of violation proposed by [14] with time, more precisely, we temporalise that logic. The resulting system allows us to capture many subtleties of the concept of legal compliance. In particular, the formal characterisation of compliance can handle different types of legal obligation and different temporal constraints over them. The logic is also able to represent, and reason about, chains of reparative obligations, since in many cases the fulfillment of these types of obligation still amount to legally acceptable situations. 1

P al au, Gl ad ys (et al i i). Lóg i c as c ond i c i onal e s y r az onami e nt o d e se nt i d o c omún. Bar c e l ona, Ge d i sa, 2004, p p. 190. P or M ar í a I né s C or b al án y Fe d e r ic o E. Lóp e z UNLP Tal como lo indica su título, la compilación está dedicada al estudio de las lógicas condicionales y del razonamiento de sentido común. Una de las características

Se llama revocables a todos aquellos razonamientos no deductivos en los cuales la conclusion es obtenida a partir de informacion incompleta es decir a partir de premisas que representan condiciones insuficientes para afirmar la conclusion. En los razonamientos revocables nueva informacion que se agregue a las premisas puede invalidar la inferencia hecha pues daria lugar a inconsistencias. Asi la relacion de inferencia que subyace a los razonamientos revocables no cumple con la propiedad de monotonia que satisface la relacion usual de inferencia deductiva. Las logicas no monotonas han surgido con la idea de formalizar este tipo de razonamientos. En este trabajo se sostendra que el problema de la revocabilidad no atane a operadores logicos ni a la logica en sentido estricto sino a como la logica es aplicada en diferentes contextos lo que implica tomar en cuenta factores externos a la caracterizacion de operadores logicos. Esta perspectiva no conduce a una modificacion de la logica sin...

We present two models of hierarchical structured multi-agents, and we describe how to obtain a modal knowledge base from distributed sources. We then propose a computationally oriented revision procedure for modal knowledge bases. This procedure is based on a labelled tableaux calculi supplemented with a formalism to record the dependencies of the formulae. The dependencies are then used to reconstruct the minimal inconsistent sets, and the sub-formulae responsible for the inconsistencies are revised according to well-defined chains of modal functions.

In the domain of Linked Open Data a need is emerging for developing automated frameworks able to generate the licensing terms associated to data coming from heterogeneous distributed sources. This paper proposes and evaluates a deontic logic semantics which allows us to define the deontic components of the licenses, i.e., permissions, obligations, and prohibitions, and generate a composite license compliant with the licensing items of the composed different licenses. Some heuristics are proposed to support the data publisher in choosing the licenses composition strategy which better suits her needs w.r.t. the data she is publishing.

Resumen: En este trabajo analizo una nocion de consecuencia 16gica falible que represento en el metalenguaje con el signo &quot; en particular reviso la nocion que creo adecuada para los razonamientos que operan con &quot;normas derrotables&quot; (ciertos condicionales no monotonicos que expreso en el lenguaje objeto con la forma &quot;A&gt;B&quot;). Sostengo que para dar cuenta de las inferencias basadas en normas derrotables debe apelarse a una nocion de consecuencia logica no deductiva que tiene analogias con la nocion de condicional derrotable (CO), pero tambien diferencias importantes. En particular, la noci6n de consecuencia 16gica falible cumple, a diferencia de los CD, con el principio de monotonia cauta, asi como con el de que un conjunto de premisas consistente no puede arrojar conclusiones contradictorias. Por tiltimo, sostengo que todo CD encubre uno estricto en el sentido de que, para todo par de formulas , el CD A&gt;B equivale a un condicional estricto /[A,B)-&gt;B. (...