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)

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)

We investigate the modal logic of stepwise removal of objects, both for its intrinsic interest as a logic of quantification without replacement, and as a pilot study to better understand the complexity jumps between dynamic epistemic logics of model transformations and logics of freely chosen graph changes that get registered in a growing memory. After introducing this logic (MLSR) and its corresponding removal modality, we analyze its expressive power and prove a bisimulation characterization theorem. We then provide a complete Hillbert-style (...) axiomatization for the logic of stepwise removal in a hybrid language enriched with nominals and public announcement operators. Next, we show that model-checking for MLSR is PSPACE-complete, while its satisfiability problem is undecidable. Lastly, we consider an issue of fine-structure: the expressive power gained by adding the stepwise removal modality to fragments of first-order logic. (shrink)

_In this paper, we support the adoption of an empirical approach in development ethics research and show that the theoretical insights and methodological guidelines in Sen’s capability approach can offer helpful guidance to development ethicists on designing and execution of such research. To this end, we show how specific insights in the CA guide one to identify and engage with relevant stakeholders in extensive dialogues about the ethical issues underlying their development practices and in gathering empirical data for further ethical (...) reflections. Drawing on an empirical development ethics research project we conducted in the fisheries sector of Ukerewe District in Tanzania, we illustrate how the CA supported us in identifying 310 representatives of various categories of small-scale fishers and stakeholders, and in designing and executing empirical development ethics research in the form of progressive stages of dialogues in stakeholder groups. The participants in these stakeholder groups reflected on and assessed their individual and collective values, capacities, roles and interests in the fisheries sector. In turn, we gathered empirical data on the nature and causes of the poverty of small-scale fishers and ways to overcome it, the __moral roots of the prevalence of institutional and professional apathy, and stakeholders’ motivations and concrete actions to support the redressing of the challenges facing small-scale fishers. Later, we used these empirical data to theorise about moving small-scale fishers from poverty to prosperity, and about the development ethic best suited to guide future initiatives in combatting poverty and generating wealth through the fisheries sector in Ukerewe District._ _Keywords: _Empirical Ethics, Development Ethics, Capability Approach, Small-scale Fisheries, Poverty, Ukerewe District, Tanzania. (shrink)

The significance of being an intellectual when taken prisoner and sent to a concentration camp by the Nazis is rarely discussed – instead, the importance of being either a Jew or a political prisoner is highlighted. By contrast, Jean Amery’s recollections of being tortured and sent to Auschwitz concentrate on his self-understanding as an intellectual. What difference does the identity and outlook as an intellectual make in the extreme circumstances found in Auschwitz? The paper discusses Amery’s views on this question, (...) invoking that of others who have also addressed it, like Primo Levi and Theodor Adorno. (shrink)

Information is a recognized fundamental notion across the sciences and humanities, which is crucial to understanding physical computation, communication, and human cognition. The Philosophy of Information brings together the most important perspectives on information. It includes major technical approaches, while also setting out the historical backgrounds of information as well as its contemporary role in many academic fields. Also, special unifying topics are high-lighted that play across many fields, while we also aim at identifying relevant themes for philosophical reflection. There (...) is no established area yet of Philosophy of Information, and this Handbook can help shape one, making sure it is well grounded in scientific expertise. As a side benefit, a book like this can facilitate contacts and collaboration among diverse academic milieus sharing a common interest in information. . First overview of the formal and technical issues involved in the philosophy of information . Integrated presentation of major mathematical approaches to information, form computer science, information theory, and logic . Interdisciplinary themes across the traditional boundaries of natural sciences, social sciences, and humanities. (shrink)

One of Heidegger’s enduring concerns was to develop an original meditation on the meaning of (the presence of) the present. Integral to this attempt is his critique of the understanding of the being of beings in terms of the objectivity of the object. In this paper, I trace Heidegger’s analyses of objectivity, through which Heidegger consistently establishes objectivity as non-primordial and derivative. In order to do this, however, Heidegger had to identify a specific, narrow (spatio-temporalized) conception of objectivity (in terms (...) of Gegenstehenlassen and Vorstellen) as the hallmark of modern philosophy. I show that it is unclear whether that conception is a justified result or rather an unjustified presupposition of his approach. I then suggest what meanings of objectivity might be lost after Heidegger, by pointing to several aspects of Hegel’s notion of objectivity that are incompatible with Heidegger’s account, to wit: the lack of ‘subject-object’-terminology in his definitions of objectivity; the special language of ‘forms of’ objectivity; Hegel’s critique of representation; his notion of Gegenstand as a content with a categorical form, and, finally, that Aristotle’s notion of hypokeimenon might provide a clue as to how Hegel’s notion of object can be understood. (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)

Two philosophical tools are used in this article, namely that of philosophical-pluralism and transcendent pluralism as a kind of glue to enhance our examining of creative pluralism. There is a diversity implant in positive modus of understanding this pluralistic pristine of creative pluralism within transcendence modus. To help facilitate this pluralistic pristine, the author makes use of three constructivist paradigms that are distinguished and used, namely exogenous constructivism emphasising the reconstruction of structures preformed in the environment; endogenous constructivism emphasising the (...) coordination of previous organismic structures and dialectical constructivism emphasising the construction of new structures out of organism and environmental interaction.Contribution: The aim of this article is to present a coherent metatheory by specifying the boundary conditions in which each root metaphor best applies. These above-mentioned versions of pluralism as tools are a reminiscence and a jubilee of the efforts made by sapiens through diversity onto or into pluralism to enable the religious hamlet to think and share. This pluralistic approach of orientation, I hope, will empower sapiens in their respective hamlets to define, articulate and designate to enhance their own epistemological and ontological vantage points wherefrom their individual, coherent and contextual ways of thinking, acting and projecting their lives in a positive modus by emphasising the reconstructions of their performance in their environment. (shrink)

In a mathematical perspective, neighborhood models for modal logic are generalized quantifiers, parametrized to points in the domain of objects/worlds. We explore this analogy further, connecting generalized quantifier theory and modal neighborhood logic. In particular, we find interesting analogies between conservativity for linguistic quantifiers and the locality of modal logic, and between the role of invariances in both fields. Moreover, we present some new completeness results for modal neighborhood logics of linguistically motivated classes of generalized quantifiers, and raise new types (...) of open problem. With the bridges established here, many further analogies might be explored between the two fields to mutual benefit. (shrink)

Over the past decades, logicians interested in rational agency and intelligent interaction studied major components of these phenomena, such as knowledge, belief, and preference. In recent years, standard ‘static’ logics describing information states of agents have been generalized to dynamic logics describing actions and events that produce information, revise beliefs, or change preferences, as explicit parts of the logical system. Van Ditmarsch, van der Hoek & Kooi 2007, Baltag, van Ditmarsch & Moss 2008, van Benthem, to appear A, are up-to-date (...) accounts of this dynamic trend (the present paper follows Chapter 9 of the latter book). But in reality, concrete rational agency contains all these dynamic processes entangled. A concrete setting for this entanglement are games – and this paper is a survey of their interfaces with logic, both static and dynamic. Games are intriguing also since their analysis brings together two major streams, or tribal communities: ‘hard’ mathematical logics of computation, and ‘soft’ philosophical logics of propositional attitudes. Of course, this hard/soft distinction is spurious, and there is no natural border line between the two sources: it is their congenial mixture that makes current theories of agency so lively. (shrink)

We articulate a relational understanding of modality, and show it at work in a survey of pre-order models, set-lifting, and modal languages.

Artikelen vanuit joods, christelijk, islamitisch en humanistisch perspectief over de mogelijkheid van tolerantie tussen met name de drie grote monotheïstische religies.

This letter responds to a letter by Moti Gorin in the same issue, September‐October 2024, of the Hastings Center Report.