Game-theoretic solution concepts describe sets of strategy profiles that are optimal for all players in some plausible sense. Such sets are often found by recursive algorithms like iterated removal of strictly dominated strategies in strategic games, or backward induction in extensive games. Standard logical analyses of solution sets use assumptions about players in fixed epistemic models for a given game, such as mutual knowledge of rationality. In this paper, we propose a different perspective, analyzing solution algorithms as processes of learning (...) which change game models. Thus, strategic equilibrium gets linked to fixed-points of operations of repeated announcement of suitable epistemic statements. This dynamic stance provides a new look at the current interface of games, logic, and computation. (shrink)

Rational agents base their actions on information from observation, inference, introspection, or other sources. But this information comes in different kinds, and it is usually handled by different logical mechanisms. We discuss how to integrate external ‘updating information’ and internal ‘elucidating information’ into one system of dynamic epistemic logic, by distinguishing two basic informational actions: ‘bare seeing’ versus ‘conscious realization’.

Dov Gabbay is a prolific logician just by himself. But beyond that, he is quite good at making other people investigate the many further things he cares about. As a result, King's College London has become a powerful attractor in our field worldwide. Thus, it is a great pleasure to be an organizer for one of its flagship events: the Augustus de Morgan Workshop of 2005. Benedikt Loewe and I proposed the topic of 'interactive logic' for this occasion, with an (...) emphasis on social software – the logical analysis and design of social procedures – and on games, arguably the formal interactive setting par excellence. This choice reflects current research interests in our logic community at ILLC Amsterdam and beyond. In this broad area of interfaces between logic, computer science, and game theory, this paper is my own attempt at playing Dov. I am, perhaps not telling, but at least asking other people to find out for me what I myself cannot. (shrink)

It is common in the literature to claim that legitimacy is the right to rule and that, accordingly, Hohfeldian rights analysis can be used to understand the concept. However, we argue that authors in the legitimacy literature have not generally realised the full potential of Hohfeldian analysis. We discuss extant approaches in the literature that conceptually identify legitimacy with one particular Hohfeldian incident, or, more rarely, a determinate set of incidents. Against these views, and building on parallel debates in property (...) theory, we suggest that Hohfeldian analysis pushes one towards the claim that legitimacy possesses no determinate essence. We provide a rationale for this novel view and disarm a series of objections. (shrink)

Where should we meet? This may seem like a trivial decision, mostly focused on convenience. However, location can represent integral values, attitudes, and priorities. Especially when the meeting i...

Whether or not capitalism is compatible with ethics is a long standing dispute. We take up an approach to virtue ethics inspired by Adam Smith and consider how market competition influences the virtues most associated with modern commercial society. Up to a point, competition nurtures and supports such virtues as prudence, temperance, civility, industriousness and honesty. But there are also various mechanisms by which competition can have deleterious effects on the institutions and incentives necessary for sustaining even these most commercially (...) friendly of virtues. It is often supposed that if competitive markets are good, more competition must always be better. However, in the long run competition enhancing policies that neglect the nurturing and support of the bourgeois virtues may undermine the continued flourishing of modern commercial society. (shrink)

Transition systems can be viewed either as process diagrams or as Kripke structures. The rst perspective is that of process theory, the second that of modal logic. This paper shows how various formalisms of modal logic can be brought to bear on processes. Notions of bisimulation can not only be motivated by operations on transition systems, but they can also be suggested by investigations of modal formalisms. To show that the equational view of processes from process algebra is closely related (...) to modal logic, we consider various ways of looking at the relation between the calculus of basic process algebra and propositional dynamic logic. More concretely, the paper contains preservation results for various bisimulation notions, a result on the expressive power of propositional dynamic logic, and a de nition of bisimulation which is the proper notion of invariance for concurrent propositional dynamic logic. (shrink)

This article proposes a systematic application of recent developments in the logic of preference to a number of topics in deontic logic. The key junction is the well‐known Hansson conditional for dyadic obligations. These conditionals are generalized by pairing them with reasoning about syntactic priority structures. The resulting two‐level approach to obligations is tested first against standard scenarios of contrary‐to‐duty obligations, leading also to a generalization for the Kanger‐Anderson reduction of deontic logic. Next, the priority framework is applied to model (...) two intuitively different sorts of deontic dynamics of obligations, based on information changes and on genuine normative events. In this two‐level setting, we also offer novel takes on vexed issues such as the Chisholm paradox and modelling strong permission. Finally, the priority framework is shown to provide a unifying setting for the study of operations on norms as such, in particular, adding or deleting individual norms, and even merging whole norm systems in different manners. (shrink)

In the last few years, preference logic and in particular, the dynamic logic of preference change, has suddenly become a live topic in my Amsterdam and Stanford environments. At the request of the editors, this article explains how this interest came about, and what is happening. I mainly present a story around some recent dissertations and supporting papers, which are found in the references. There is no pretense at complete coverage of preference logic (for that, see Hanson 2001) or even (...) of preference change (Hanson 1995). (shrink)

The Movement of Showing investigates the idea, shared by Derrida, Hegel and Heidegger, that the value of their thought is not found in its results or conclusions, but in its "movement." All three describe the heart of their work in terms of a pathway, development, or movement rather than in terms of its propositions or conclusions. This seems to deprive their thought of a solid ground, and indeed deconstruction in particular is often criticized in this way. Johan de Jong (...) argues that this is a structural vulnerability that is both its weakness and the source of its value, tracing Derrida's indirect method from his early to later works, and considering his engagements with Hegel and Heidegger. His analysis locates an affinity among Hegel, Heidegger and Derrida in a shared distrust of externality and, against the grain of some Levinasian commentaries, argues that Derrida's indirectness results in an ethics of complicity. The Movement of Showing answers a central question that many polemics about continental philosophy and postmodernism revolve around concerning how, methodologically, one can philosophize responsibly. It shows the difference between critique and polemics, and why simply taking up a position for or against is insufficient in order to think responsibly. (shrink)

How can we assess the epistemic quality of democratic decision-making? Sceptics doubt such assessments are possible, as they must rely on controversial substantive standards of truth and rightness. Challenging that scepticism, this paper suggests a procedure-independent standard for assessing the epistemic quality of democratic decision-making by evaluating whether it is adequately supported by reasons. Adequate support for conclusion is a necessary aspect of epistemic quality for any epistemic justification of democracy, though particularly relevant to theories that emphasize public deliberation. Finding (...) existing methods for measuring the quality of public discourse to fall short, we draw on an epistemological theory of argumentation to provide a more sophisticated approach to evaluating the epistemic quality of democratic decision-making, illustrate how the approach can be used, and demonstrate its relevance for the epistemic turn in democratic theory. (shrink)

We propose strategic games wherein the strategies consist of players asking each other questions and answering those questions. We study simplifications of such games wherein two players simultaneously ask each other a question that the opponent is then obliged to answer. The motivation for our research is to model conversation including the dynamics of questions and answers, to provide new links between game theory and dynamic logics of information, and to exploit the dynamic/strategic structure that, we think, lies implicitly inside (...) epistemic models for epistemic languages, and to make that structure an explicit subject of logical study. Our main contributions are: the notion of a two-person question-answer game with information goals, the existence and computation of equilibria for these games, the correspondence with Bayesian games and their equilibria, and a connection between logic and game theory namely the existence of equilibria for positive goal formulae. (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 extend earlier epistemic “awareness models” into a dynamic system that includes acts of public observation, but also adding and dropping formulas from the currently ‘entertained’ set, we give a completeness theorem, and we show how this dynamics updates explicit knowledge. Similar ideas have been proposed before, but they were restricted to update with factual propositions; our new dynamic system applies to arbitrary formulas. We also extend our approach to multi-agent scenarios where awareness changes may happen privately. Finally, we mention further directions and related approaches. (shrink)

This paper develops propositions on the added value for SMEs of normatively based, employee-oriented corporate social responsibility (CSR). We suggest that not only motives but also the skills of the owner/manager as an institutional entrepreneur are critical in dealing with institutional variance. Also, the transfer of employee-oriented CSR can have positive results for SMEs that could imply that globalisation is not only a race to the bottom.

Sportfilosofie en haar centrale vragen Sportfilosofie heeft haar academische wortels in de jaren zeventig van de vorige eeuw, met de oprichting van de International Association for the Philosophy of Sport en het Journal of the Philosophy of Sport . In Nederland heeft sportfilosofie een academische plek verworven aan het begin van de jaren negentig aan de Faculteit der Bewegingswetenschappen.

This article shows how eco-theology could and should be indigenised in an African context using the Copperbelt in Zambia as a case study. The ecological crisis worldwide has given rise to the call for everyone to work together to start caring about our natural environment. In theology, the response to this call received the name eco-theology. By means of a literature review, ethnographic information and governmental legislation, the article tries to illustrate how eco-theology could and should be indigenised in an (...) African context using the Copperbelt in Zambia as a case study. This article makes an attempt to contribute to the needed ecological renewal by reinterpreting two traditions that inform thinking on the Copperbelt: Christianity and African traditional religion. The supernatural belief of the Lamba people is no longer embodied in this creation, and it is not too late for the people to form any indigenous environmental protection movement to protect the sacredness of mother Earth from further contamination and exploitation by strengthening, maintaining and respecting the traditional teachings and the cultural laws. Obedience to God’s command to tend creation is a quest for continued creation by humans, so that value is added to what is already in existence. This is embodied making the place we live in more beautiful, appealing and peaceful. Fruitfulness with sustainability becomes core values for interdependence and earth keeping.Contribution: We wish to address the ecological situation of the mining industry in Zambia from a theological perspective by assessing the impact of the copper mining and processing industry on humans, their environment and nature and by showing how the traditions of African traditional religion thought can be transformed into tools to oppose this ecological disaster. (shrink)

Natural languages are vehicles of information, arguably the most important, certainly the most ubiquitous that humans possess. Our everyday interactions with the world, with each other and with ourselves depend on them. And even where in the specialised contexts of science we use dedicated formalisms to convey information, their use is embedded in natural language. This omnipresence of natural language is due in large part to its flexibility, which is almost always a virtue, sometimes a vice. Natural languages are able (...) to carry information in a wide variety of ways, about a seemingly unlimited range of topics, which makes them both efficient and versatile, and hence useful in almost every circumstance. But sometimes, when pinpoint precision is what counts, this versatility can get in the.. (shrink)

Keuze van artikelen uit het werk van de Vlaamse filosoof over wetenschap, milieu, en medische en biologische ethiek.

This study explores how being satisfied with one’s life as an entrepreneur is a crucial ethical and psychological outcome of early volition and, subsequently, a vital resource in the development of a richer eudaimonic experience from entrepreneurship. We develop and test our predictions based on two independent datasets: American and Swedish business owners and early stage entrepreneurs. We argue and demonstrate that satisfaction with life as an entrepreneur conveys a distinct state of entrepreneurial well-being and constitutes a crucial self-evaluation which (...) mediates the effects of early volition in entrepreneurship on long-term eudaimonia. We contribute to the emerging conversations on entrepreneurship, business ethics, and well-being. (shrink)

Is Nederland een fraudeland geworden? Na alle berichten over boekhoudschandalen en het bekend worden van illegale prijsafspraken is het terecht dat die vraag wordt gesteld. Het oplichten van aandeelhouders of van klanten gaat in tegen verschillende ethische noties. Het verstrekken van onjuiste informatie is niet alleen vanuit een utilistisch standpunt verwerpelijk vanwege de economische schade die ontstaat doordat een optimale marktwerking belemmerd wordt. Ook vanuit een deontologisch perspectief staan de ethische seinen op rood: het bedriegen van aandeelhouders of klanten getuigt (...) van weinig respect en is onrechtvaardig omdat dit zelfverrijking mogelijk maakt ten koste gaat van de stakeholders. Ook vanuit het perspectief van de deugdenethiek zijn deze praktijken verwerpelijk: het achterhouden van informatie getuigt van een gebrek aan integriteit en heeft een negatieve voorbeeldfunctie naar anderen. (shrink)

Hot spot policing is an established concept that is proven to reduce crime. It is mostly done through foot patrol or car patrols. In the present study it is tested whether helicopters can produce a deterrent policing effect to reduce the amount of vehicle arsons in Sweden on larger hot areas. Sweden tends to have elevated levels of vehicle arsons in August, with about 20% of police districts responsible for 50% of the cases. The risk narrative revolves around youth congregating (...) in public places in deprived neighborhoods to generate disturbances, and the disruption of the risk narrative tested here is based on providing deterrence through helicopter police presence. During 6 weeks in August and September of 2019 police helicopters patrolled four police districts in Sweden to attempt to prevent vehicle arsons. Our data comprise police reports of vehicle arson, and time stamped satellite data over the location for police helicopters. The evaluation considers whether there is an intention to treat effect from this project, in addition to whether there is an effect of actual helicopter presence. The study finds no significant effect of intention to treat, nor of actual dosage. (shrink)

The meaning of have is notoriously difficult to define; sometimes it seems to denote possession, but often, it seems to denote nothing, only to complicate composition. This paper focuses on the cases where have embeds a small clause, proposing that all it accomplishes is abstraction, turning the small clause into a predicate. This analysis is extended to the cases where have appears to embed DPs: These objects are interpreted as small clauses as well, with implicit predicates denoting possession or—with relational (...) nouns—nothing. (shrink)

This book is a philosophical enquiry into the educational consequences of Spinoza’s political theory. Spinoza’s political theory is of particular interest for educational thought as it brings together the normative aims of his ethical theory with his realistic depiction of human psychology and the ramifications of this for successful political governance. As such, the book aims to introduce the reader to Spinoza’s original vision of civic education, as a project that ultimately aims at the ethical flourishing of individuals, while being (...) carefully tailored and adjusted to the natural limitations of human reason. This author-meets-critics includes scholars in philosophy, education and Spinoza studies. (shrink)