Classical epistemic logic describes implicit knowledge of agents about facts and knowledge of other agents based on semantic information. The latter is produced by acts of observation or communication that are described well by dynamic epistemic logics. What these logics do not describe, however, is how significant information is also produced by acts of inference— and key axioms of the system merely postulate "deductive closure". In this paper, we take the view that all information is produced by acts, and hence (...) we also need a dynamic logic of inference steps showing what effort on the part of the agent makes a conclusion explicit knowledge. Strong omniscience properties of agents should be seen not as static idealizations, but as the result of dynamic processes that agents engage in. This raises two questions: (a) how to define suitable information states of agents and matching notions of explicit knowledge, (b) how to define natural processes over these states that generate new explicit knowledge. To this end, we use a static base from the existing awareness literature, extending it into a dynamic system that includes traditional acts of observation, but also adding and dropping formulas from the current ' awareness' set. We give a completeness theorem, and we show how this dynamics updates explicit knowledge. Then we extend our approach to multi-agent scenarios where awareness changes may happen privately. Finally, we mention further directions and related approaches. Our contribution can be seen as a ' dynamification' of existing awareness logics. (shrink)

We investigate dynamic operations acting over a knowing how logic. Our approach makes use of a recently introduced semantics for the knowing how operator, based on an indistinguishability relation between plans. This semantics is arguably closer to the standard presentation of knowing that modalities in classic epistemic logic. Here, we discuss how the semantics enables us to define dynamic modalities representing different ways in which an agent can learn how to achieve a goal. In this regard, we study two types (...) of updates: ontic updates (for which we provide axiomatizations over a particular class of models), and epistemic updates (for which we investigate some semantic properties). (shrink)

Epistemic logic with its possible worlds semantic model is a powerful framework that allows us to represent an agent’s information not only about propositional facts, but also about her own information. Nevertheless, agents represented in this framework are logically omniscient: their information is closed under logical consequence. This property, useful in some applications, is an unrealistic idealisation in some others. Many proposals to solve this problem focus on weakening the properties of the agent’s information, but some authors have argued that (...) solutions of this kind are not completely adequate because they do not look at the heart of the matter: the actions that allow the agent to reach such omniscient state. Recent works have explored how acts of observation, inference, consideration and forgetting affect an agent’s implicit and explicit knowledge; the present work focuses on acts that affect an agent’s implicit and explicit beliefs. It starts by proposing a framework in which these two notions can be represented, and then it looks into their dynamics, first by reviewing the existing notion of belief revision, and then by introducing a rich framework for representing diverse forms of inference that involve both knowledge and beliefs. (shrink)

This work proposes an understanding of deductive, default and abductive reasoning as different instances of the same phenomenon: epistemic dynamics. It discusses the main intuitions behind each one of these reasoning processes, and suggest how they can be understood as different epistemic actions that modify an agent’s knowledge and/or beliefs in a different way, making formal the discussion with the use of the dynamic epistemic logic framework. The ideas in this paper put the studied processes under the same umbrella, thus (...) highlighting their relationship and allowing a better understanding of how they interact together. (shrink)

Among the non-monotonic reasoning processes, abduction is one of the most important. Usually described as the process of looking for explanations, it has been recognized as one of the most commonly used in our daily activities. Still, the traditional definitions of an abductive problem and an abductive solution mention only theories and formulas, leaving agency out of the picture. Our work proposes a study of abductive reasoning from an epistemic and dynamic perspective. In the first part we explore syntactic definitions (...) of both an abductive problem in terms of an agent’s information and an abductive solution in terms of the actions that modify the agent’s information. We look at diverse kinds of agents, including not only omniscient ones but also those whose information is not closed under logical consequence and those whose reasoning abilities are not complete. In the second part, we look at an existing logical framework whose semantic model allows us to interpret the previously stated formulas, and we define two actions that represent forms of abductive reasoning. (shrink)

The paper develops an interface between syntax-based logical models of awareness and dynamic epistemic logic. The framework is shown to be able to accommodate a variety of notions of awareness and knowledge, as well as their dynamics. This, it is argued, offers a natural formal environment for the analysis of epistemic phenomena typical of multi-agent information exchange, such as how agents become aware of relevant details, how they perform inferences and how they share their information within a group. Technically, the (...) logics presented are all simple refinements of the logic of public announcements. (shrink)

As a new type of epistemic logics, the logics of knowing how capture the high-level epistemic reasoning about the knowledge of various plans to achieve certain goals. Existing work on these logics focuses on axiomatizations; this paper makes the first study of their model theoretical properties. It does so by introducing suitable notions of bisimulation for a family of five knowing how logics based on different notions of plans. As an application, we study and compare the expressive power of these (...) logics. (shrink)

This paper introduces and studies a notion of cautious distributed belief. Different from the standard distributed belief, the cautious distributed belief of a group is inconsistent only when all group members are individually inconsistent. The paper presents basic results about cautious distributed belief, investigates whether it preserves properties of individual belief, and compares it with standard distributed belief. Although both notions are equivalent in the class of reflexive models, this is not the case in general. While we argue that an (...) understanding of the concept of cautious distributed belief from first principles is important, cautious distributed belief can be expressed using standard distrbuted belief and we show that the propositional language extended only with cautious distributed belief is in fact strictly less expressive than the propositional language extended only with standard distributed belief. We, finally, identify a small extension of the language making the former as expressive as the latter. (shrink)

In this paper, we explore the relation between an agent’s doxastic attitude and her arguments in support of a given claim. Our main contribution is the design of a logical setting that allows us reason about binary arguments which are either in favour or against a certain claim. This is a setting in which arguments and propositions are the basic building blocks so that the concept of argument-based belief emerges in a straightforward way. We work against the background of Dung’s (...) abstract argumentation framework, extending it to a new setting in which we can study the formal properties of binary arguments as well as the larger structures they establish. This paper introduces a formal ‘two-dimensional’ language to talk about propositions and arguments, for which a sound and complete axiom system is provided. (shrink)

The paper focuses on a recent challenge brought forward against the interventionist approach to the meaning of counterfactual conditionals. According to this objection, interventionism cannot account for the interpretation of right-nested counterfactuals, the problem being its strict interventionism. We will report on the results of an empirical study supporting the objection. Furthermore, we will extend the well-known logic of intervention with a new operator expressing an alternative notion of intervention that does away with strict interventionism. This new notion of intervention (...) operates on the valuation of the variables in a causal model, and not on their functional dependencies. (shrink)

This manuscript presents a topological argumentation framework for modelling notions of evidence-based (i.e., justified) belief. Our framework relies on so-called topological evidence models to represent the pieces of evidence that an agent has at her disposal, and it uses abstract argumentation theory to select the pieces of evidence that the agent will use to define her beliefs. The tools from abstract argumentation theory allow us to model agents who make decisions in the presence of contradictory information. Thanks to this, it (...) is possible to define two new notions of beliefs, grounded beliefs and fully grounded beliefs. These notions are discussed in this paper, analysed and compared with the existing notion of topological justified belief. This comparison revolves around three main issues: closure under conjunction introduction, the level of consistency and their logical strength. (shrink)

This paper is part of an on-going programme on the study of the logical aspects of social network formation. It recalls the so-called social network model, discussing the properties of a notion of closeness between agents ; then introduces an extended social network model in which different agents might assign different values to different traits, discussing the properties of the notion of weighted closeness that arises. These notions are used to define social network creation operations by means of a threshold (...) strategy. The paper studies the properties of the social networks the updates create, providing sound and complete axiom systems for formal languages describing these updates’ effects. (shrink)

Abductive problems and their solutions are presented by means of justification logic. We introduce additional meta-constructions in order to generate and compare different solutions to the same abductive problem. Our approach has three advantages: (i) it makes structurally explicit the solution to an abductive problem (as it has a syntactic nature); (ii) it gives a precise meaning to the notion of evidence; (iii) it provides clear definitions and procedures for the comparison of solutions that can be adapted to different needs.

We look at two fundamental logical processes, often intertwined in planning and problem solving: inference and update. Inference is an internal process with which we uncover what is implicit in the information we already have. Update, on the other hand, is produced by external communication, usually in the form of announcements and in general in the form of observations, giving us information that might not have been available (even implicitly) before. Both processes have received attention from the logic community, usually (...) separately. In this work, we develop a logical language that allows us to describe them together. We present syntax, semantics and a complete axiom system; we discuss similarities and differences with other approaches and mention how the work can be extended. (shrink)

Classical epistemic logic describes implicit knowledge of agents about facts and knowledge of other agents based on semantic information. The latter is produced by acts of observation or communication that are described well by dynamic epistemic logics. What these logics do not describe, however, is how significant information is also produced by acts of inference—and key axioms of the system merely postulate “deductive closure”. In this paper, we take the view that all information is produced by acts, and hence we (...) also need a dynamic logic of inference steps showing what effort on the part of the agent makes a conclusion explicit knowledge. Strong omniscience properties of agents should be seen not as static idealizations, but as the result of dynamic processes that agents engage in. This raises two questions: (a) how to define suitable information states of agents and matching notions of explicit knowledge, (b) how to define natural processes over these states that generate new explicit knowledge. To this end, we use a static base from the existing awareness literature, extending it into a dynamic system that includes traditional acts of observation, but also adding and dropping formulas from the current ‘awareness’ set. We give a completeness theorem, and we show how this dynamics updates explicit knowledge. Then we extend our approach to multi-agent scenarios where awareness changes may happen privately. Finally, we mention further directions and related approaches. Our contribution can be seen as a ‘dynamification’ of existing awareness logics. (shrink)

Scholars have debated the meaning of the foreign-relations clauses in the U.S. Constitution. This essay attempts to outline the foreign-relations clauses that an ideal constitution should have. A liberal constitution must enable the government to implement a morally defensible foreign policy. The first priority is the defense of liberty. The constitution must allow the government to effectively defend persons, territory, and liberal institutions themselves. The liberal government should also contribute to the advancement of global freedom, subject to a number of (...) conditions, especially cost. The essay recommends improved methods to incorporate treaties and customary international law into the constitutional structure. Treaties should be approved by the whole legislature and should generally be self-executing. Customary law should be genuine, not fake, and consistent with liberal principles. Finally, based on economic theory and evidence, the essay recommends that liberal constitutions prohibit the government from erecting trade barriers. It concludes by tentatively proposing concrete constitutional language to implement these recommendations. (shrink)

This work offers an analysis of all the legal and moral issues surrounding humanitarian intervention: the deaths of innocent persons and the Doctrine of Double Effect Governmental legitimacy - The Doctrine of Effective Political Control; UN Charter and evaluation of the Nicaragua ruling; The Morality of not intervening; US-led invasion of Iraq; Humanitarian intervention authorised by the UN Security Council - Iraq, Somalia, Haiti, Rwanda, and Bosnia among others highlight NATO's intervention in Kosovo; The Nicaragua Decision; and The precedents of (...) Panama, Liberia and Sierra Leone. The book's features include: a new framework based on the doctrine of double effect; basic principles of international ethics; outline of the moral argument for humanitarian intervention; explores the morality and legality of military action to end tyranny or anarchy; arguments in a much more detailed and complete fashion than in previous editions; in-depth examination of philosophy of international law; the relationship between custom and moral theory; new discussion of the question of right authority; and a full analysis of recent interventions in Kosovo and Iraq. book addresses a broad interdisciplinary audience of international lawyers, philosophers, and political scientists. In this new edition, the author responds to critics while updating the discussion in the light of the momentous events that took place at the beginning of the new millennium. (shrink)

The war in Iraq has reignited the passionate humanitarian intervention debate. President George W. Bush surprised many observers in his second inaugural address when he promised to oppose tyranny and oppression, and this in a world not always willing or ready to join in that fight. Humanitarian intervention is again on the forefront of world politics.

Abstract The article addresses three aspects of the humanitarian intervention doctrine. It argues, first, that the value of sovereignty rests on the justified social processes of the target state ? the horizontal contract. Foreign interventions, even when otherwise justified, must respect the horizontal contract. In contrast, morally objectionable social processes (such as the subjection of women) are not protected by sovereignty (intervention, of course, may be banned for other reasons). In addition, tyrants have no moral protection against interventions directed at (...) them. Second, the article addresses the internal legitimacy of humanitarian intervention. It concludes that the liberal state may only use voluntary soldiers (either the voluntary army or mercenaries) to conduct humanitarian intervention. Conscription for that purpose is not permissible. The article shows that the long-standing criticism of mercenaries stems from a romantic prejudice and is thus unfair. Third, the article makes a distinction between intention (the determination to perform an action) and motive (a further goal that the agent seeks with that action) and shows that only intention is relevant for humanitarian intervention. A justified humanitarian intervention requires the intention to liberate the victims, but not necessarily a good further motive. It shows how mainstream doctrine has impermissibly confused the two concepts. (shrink)

Research Articles Fernando R. Tesón, Social Philosophy and Policy, FirstView Article.

Teson critiques a recent article by John Rawls in which Rawls extends his acclaimed political theory to include international relations.

Economists generally agree that free trade leads to economic growth. This proposition is supported both by theoretical models and empirical data. Further, while the empirical evidence is more limited on this question, the general consensus among economists holds that trade restrictions are likely to hurt the poor. Even if the latter consensus turns out to be wrong, if free trade leads to superior growth, governments would have more resources to redistribute to the poor. It is surprising then that philosophers and (...) human rights scholars do not advocate liberalizing trade as a way to improve the welfare of the poor as a class. While many scholars in these fields are silent with respect to the effect of free trade on the poor, some actually argue that liberalized trade is harmful for the poor, contrary to the claims of economists. In this article, we argue that any serious scholar concerned with the plight of the poor needs to address the theory and evidence regarding the effects of trade liberalization on economic growth, suggesting that the standard policy prescriptions of the philosophers and human rights scholars are, at best, of second order concern and, at worst, likely to be counterproductive in terms of improving the welfare of the poor. (shrink)

Tras la llegada de los conquistadores españoles y durante los dos siglos del reinado de su monopolio, no se permitió el ingreso de extranjeros y la población permaneció distribuida en las regiones, en proporciones casi inversas a las actuales. Con la caída del régimen español y los avances del monopolio inglés, comenzó a desplazarse el centro territorial argentino desde el Noroeste hacia el Litoral y a producirse variaciones en la dinámica demográfica. El establecimiento del modelo agroexportador produjo una afluencia excepcional (...) de inmigrantes de ultramar, que generaron cambios vertiginosos en la estructura de la población. Asimismo, el fin del modelo agroexportador que provocó la abrupta interrupción del flujo inmigratorio de ultramar, generó nuevamente otro intenso cambio demográfico que incidió en la estructura poblacional hasta la actualidad. Este artículo se centra en el movimiento migratorio que produjo el modelo agroexportador, con el objetivo de analizar sus efectos en el ritmo de crecimiento de la población, en la distribución de las variables demográficas básicas —sexo y edad—, y en los cambios en la distribución espacial, siendo su fuente principal los censos nacionales de población realizados hasta la actualidad. (shrink)

"If being a humanitarian imperialist means advocating that the hegemon use its might to advance freedom, human rights, and democracy, then I am a humanitarian imperialist.".

This essay examines the many problems with public and private development aid and argues that global liberalization of trade and immigration would have a greater direct effect in reducing global poverty. It also examines and rejects the view that people in rich countries have a strong moral obligation to give to the global poor. Such an obligation is in tension with an ethic that prizes personal projects. A political morality of equal respect and concern is congenial not with foreign aid, (...) but with recognizing the agency of the global poor by lifting the many obstacles they currently face to participating in the market as producers and consumers. (shrink)

When can a group legitimately form its own state? Under international law, some groups can but others cannot. But the standard is unclear, and traditional legal analysis has failed to elucidate it. In The Theory of Self-Determination, leading scholars chart new territory in our theoretical conception of self-determination. Drawing from diverse scholarship in international law, philosophy, and political science, they attempt to move beyond the prevailing nationalist conceptions of group definition. At issue are such universal questions as: when does a (...) group qualify as a 'people'? Does history matter? Or is it a question of ethnic status? Are these matters properly solved by popular vote? Anchored in modern analytical political philosophy but with implications for a wide range of scholarship, this volume will prove essential for scholars and practitioners of international law, global justice, and international relations. (shrink)

:This essay argues that the territorial rights of states derive from the property rights of the individuals that make up those states. The argument draws from the Lockean tradition of justification of political powers. Persons in the state of nature have natural rights. Those rights are first-order substantive rights, and second-order executive rights In the social contract, individuals transfer to the state their executive rights, not their substantive rights. The state can thus define the boundaries of property rights and adjudicate (...) property disputes, but does not legitimately own land itself. The article discusses and rejects, for deontic and consequentialist reasons, positions that justify collective and state ownership of territory. Some important consequences follow from the argument: First, no actual state has territorial rights, since no actual state wields delegated powers in land. Second, notwithstanding the preceding conclusion, actual states have an obligation to exercise their territorial powers consistently with the respect for private property. (shrink)

The present paper aims at investigating the meaning and scope of the idea of musical dissonance in The Birth of Tragedy. In reviewing the possible explanatory definitions of this concept, within and outside the speculative-theoretical framework proper to Nietzsche’s first book, we hope to open a path that leads us to rethink the so-called “artist metaphysics”, and, specially, what is generally understood as Dionysian music.

When is humanitarian intervention legitimate and how should such interventions be conducted? This article sets out eight liberal principles that underlie humanitarian intervention, some of them abstract principles of international ethics and others more concrete principles that apply specifically to humanitarian intervention. It argues that whilst these principles do not determine the legitimacy of particular interventions, they should ?incline? our judgments towards approval or disapproval. The basic principles include the liberal idea that governments are the mere agents of the people, (...) that tyrannical governments forfeit their legal protections, that human rights entail obligations for governments, that justifiable intervention must intend the end of tyranny or anarchy, that the doctrine of double-effect should be respected, that intervention is only warranted in severe cases, that intervention be welcomed by those it is intended to save, and that ideally it is welcomed by the community of democratic states. (shrink)

Teson critiques a recent article by John Rawls in which Rawls extends his acclaimed political theory to include international relations.

Name der Zeitschrift: Nietzsche-Studien Jahrgang: 47 Heft: 1 Seiten: 340-363.

Resumo Longe de pretender esgotar possíveis semelhanças entre Nietzsche e Quine, o texto que se segue tenciona mostrar, mediante comparações paradigmáticas e admissíveis convergências metodológicas, como ambos os autores, lançando mão de hipóteses naturalistas para interpretar o conhecimento e a estética, respectivamente, tornam possível pensar num naturalismo menos confinante e mais inventivo, livre dos prejuízos do cientificismo e mais condizente com a sensibilidade artística em geral.Far from intending to exhaust all the possible similarities between Nietzsche and Quine, the following text (...) aims at showing, through paradigmatic comparisons and admissible methodological convergences, how both authors - by making naturalistic assumptions to interpret knowledge and aesthetics respectively - allow us to think of a less confining and more creative naturalism, free from the prejudices of scientism and more compatible with the artistic sensibility in general. (shrink)

Resumo: O propósito geral do presente texto consiste em introduzir o sentido e o alcance que noção de improvisação musical pode adquirir no filosofar nietzschiano, e, em especial, no assim chamado período de maturidade de seu itinerário intelectual. Tenciona-se indicar que tal ideia assume uma função reguladora em seu pensamento, possibilitando lançar uma intensiva luz sobre o seu legado e enfatizar, sobretudo, o caráter pluralista e dinâmico deste último.: The present text aims at introducing the meaning and the scope that (...) the notion of musical improvisation may acquire within Nietzsche’s thought - especially in the light of thehis latter writings. It also intends to show that such idea performs a regulatory function within his thought and allows us, at the same time, to shed a bright light on his legacy, serving first and foremost to emphasize its pluralistic and dynamic character. (shrink)

Este artículo se centra en la comparación entre el sultán marroquí Aḥmad al-Manṣūr y el santo de Fez Aḥmad Ibn ‛Abd Allāh Ma‛an. A través de esa comparación, se intenta subrayar el carácter comunicativo de la sacralización del poder, basada en la utilización de determinados recursos retóricos. El análisis de algunos de esos recursos en el caso de Aḥmad al-Mansūr demuestra la dificultad de sacralizar el poder, teniendo en cuenta especialmente el punto de vista de la recepción del discurso.