In this paper we formalize an approach to knowledge that we call Interrogative Epistemology, in the spirit of Hintikka’s “interrogative model” of knowledge. According to our approach, an agent’s knowledge is shaped and limited by her interrogative agenda. The dynamic correlate of this postulate is our Selective Learning principle: the agent’s agenda limits her potential for knowledge-acquisition. Only meaningful information, that is relevant to one’s issues, can really be learnt. We use this approach to propose a new perspective on group (...) knowledge, understood in terms of the epistemic potential of a group of agents: the knowledge that the group may come to possess in common after all members share their individual information. We argue that the standard notions of group knowledge studied in the literature, ranging from distributed knowledge to common knowledge, do not give us a good measure of a group’s epistemic potential. Common knowledge is too weak and too “static”, focusing on what the agents can coordinate upon only based on their actual, current knowledge, thus disregarding testimonial knowledge. In contrast, the concept of distributed knowledge is too strong, being based on the assumption that agents can completely internalize all the testimonial evidence received from others, irrespective of the limitations posed by their own interrogative agendas. We show that a group’s true epistemic potential typically lies in between common knowledge and distributed knowledge. We propose a logical formalization of these concepts, which comes together with a complete axiomatization, and we use this setting to explain both the triumphs and the failures of collective knowledge, treating examples that range from “collective scientific knowledge” [14, 35, 43] to the so-called “curse of the committee”. (shrink)

In this paper we show how recent concepts from Dynamic Logic, and in particular from Dynamic Epistemic logic, can be used to model and interpret quantum behavior. Our main thesis is that all the non-classical properties of quantum systems are explainable in terms of the non-classical flow of quantum information. We give a logical analysis of quantum measurements (formalized using modal operators) as triggers for quantum information flow, and we compare them with other logical operators previously used to model various (...) forms of classical information flow: the “test” operator from Dynamic Logic, the “announcement” operator from Dynamic Epistemic Logic and the “revision” operator from Belief Revision theory. The main points stressed in our investigation are the following: (1) The perspective and the techniques of “logical dynamics” are useful for understanding quantum information flow. (2) Quantum mechanics does not require any modification of the classical laws of “static” propositional logic, but only a non-classical dynamics of information. (3) The main such non-classical feature is that, in a quantum world, all information-gathering actions have some ontic side-effects. (4) This ontic impact can affect in its turn the flow of information, leading to non-classical epistemic side-effects (e.g. a type of non-monotonicity) and to states of “objectively imperfect information”. (5) Moreover, the ontic impact is non-local: an information-gathering action on one part of a quantum system can have ontic side-effects on other, far-away parts of the system. (shrink)

Understanding Sankara brings together the essays of the late Richard De Smet, SJ (1916-1997) on the great Indian Advaitin. With the help of his discovery of a doctrine of laksana (analogy) in Sankara, De Smet challenges the traditional interpretation of the acarya as an illusionistic mayavadin. He also attempts a dialogue between Sankara's Advaita and Christianity, especially as represented by Thomas Aquinas. The present collection makes available this important contribution to Indology and opens it up to dialectic and dialogue.

We present a conceptual analysis of the notions of actual physical property and potential physical property as used by theoretical physicists/mathematicians working in the domain of operational quantum logic. We investigate how these notions are being used today and what role they play in the specified field of research. In order to do so, we will give a brief introduction to this area of research and explain it as a part of the discipline known as “mathematical metascience”. An in depth (...) analysis of Aristotle’s use of the notions of “actuality” and “potentiality” is presented in order to point out exactly how much of the Aristotelian connotations are embedded in the contemporary use of the concepts under investigation. Although we will not focus in depth on all the drawbacks in the early historical development of physics due to the overwhelming influence of Aristotle’s writings, our analysis does touch upon some aspects of the Aristotelian theory of movement that are often overthrown nowadays. (shrink)

The advent of personal genomics companies offering direct translation of scientific data into personal health information, calls into question traditional policies to refuse disclosure of such scientific data to research participants. This seems especially true for population biobanks, as they collect not only genotype information but also associated phenotype information, and thus may be in a unique position to translate their scientific findings into personal health information for their participants. Disclosure of such information seems mandated by the expectations raised by (...) biobanks ('to help bring about the era of personalized medicine') and their participants' rights to know health information, to know clinical research results, to life and health and particularly their right to benefit. Refusals to disclose such information can be grounded in the lack of analytical validity and/or clinical utility of most findings, the need to avoid the therapeutic misconception, the complexity and costs involved in translation and disclosure and the disproportionate burden resulting from the obligation to respect participants' right not to know before any disclosure can be made. Currently, any demands by participants in population biobanks for full disclosure of all pertinent personal health information potentially resulting from the biobank's scientific findings are unlikely to be granted by a Dutch court under Dutch and international law. As the law stands now, a population biobank is neither a doctor nor a personal genomics company. However, in view of the rapid scientific, medical, technological, commercial and social developments, population biobanks must prepare to take more care of their participants' legitimate interest in receiving as much validated personal health information as reasonably possible, in a timely fashion, by developing appropriate translation and disclosure mechanisms. This paper examines whether population biobank participants have the right, under Dutch civil law and international law, to full disclosure, i.e. to all information generated by the biobank that is pertinent to their present and future health. It pioneers the format of a hypothetical court case to elucidate the legal and policy arguments" for and against full disclosure. (shrink)

The advent of personal genomics companies offering direct translation of scientific data into personal health information, calls into question traditional policies to refuse disclosure of such scientific data to research participants. This seems especially true for population biobanks, as they collect not only genotype information but also associated phenotype information, and thus may be in a unique position to translate their scientific findings into personal health information for their participants. Disclosure of such information seems mandated by the expectations raised by (...) biobanks and their participants' rights to know health information, to know clinical research results, to life and health and particularly their right to benefit. Refusals to disclose such information can be grounded in the lack of analytical validity and/or clinical utility of most findings, the need to avoid the therapeutic misconception, the complexity and costs involved in translation and disclosure and the disproportionate burden resulting from the obligation to respect participants' right not to know before any disclosure can be made. Currently, any demands by participants in population biobanks for full disclosure of all pertinent personal health information potentially resulting from the biobank's scientific findings are unlikely to be granted by a Dutch court under Dutch and international law. As the law stands now, a population biobank is neither a doctor nor a personal genomics company. However, in view of the rapid scientific, medical, technological, commercial and social developments, population biobanks must prepare to take more care of their participants' legitimate interest in receiving as much validated personal health information as reasonably possible, in a timely fashion, by developing appropriate translation and disclosure mechanisms. This paper examines whether population biobank participants have the right, under Dutch civil law and international law, to full disclosure, i.e. to all information generated by the biobank that is pertinent to their present and future health. It pioneers the format of a hypothetical court case to elucidate the legal and policy arguments" for and against full disclosure. (shrink)

Although we applaud the interactivist approach to language and communication taken in the target article, we notice that Shanker & King (S&K) give little attention to the theoretical frameworks developed by dynamical system theorists. We point out how the dynamical idea of causality, viewed as multidirectional across multiple scales of organization, could further strengthen the position taken in the target article.

We analyze G.M. Hardegree's interpretation of the Sasaki hook as a Stalnaker conditional and explain how he makes use of the basic conceptual machinery of OQL, i.e. the operational quantum logic which originated with the Geneva Approach to the foundations of physics. In particular we focus on measurements which are ideal and of the first kind, since these encode the content of the so-called Sasaki projections within the Geneva Approach. The Sasaki projections play a fundamental role when analyzing the condition (...) under which the properties expressed by Sasaki hooks can be considered as actual. We finish with a note on how the Sasaki hook can be conceived as ``assigning causes for properties to be actual", which links the interpretation of G.M. Hardegree to what has been called ``dynamic OQL". (shrink)

We address the old question whether a logical understanding of Quantum Mechanics requires abandoning some of the principles of classical logic. Against Putnam and others (Among whom we may count or not E. W. Beth, depending on how we interpret some of his statements), our answer is a clear "no". Philosophically, our argument is based on combining a formal semantic approach, in the spirit of E. W. Beth's proposal of applying Tarski's semantical methods to the analysis of physical theories, with (...) an empirical-experimental approach to Logic, as advocated by both Beth and Putnam, but understood by us in the view of the operationalrealistic tradition of Jauch and Piron, i. e. as an investigation of "the logic of yes-no experiments" (or "questions"). Technically, we use the recently-developed setting of Quantum Dynamic Logic (Baltag and Smets 2005, 2008) to make explicit the operational meaning of quantum-mechanical concepts in our formal semantics. Based on our recent results (Baltag and Smets 2005), we show that the correct interpretation of quantum-logical connectives is dynamical, rather than purely propositional. We conclude that there is no contradiction between classical logic and (our dynamic reinterpretation of) quantum logic. Moreover, we argue that the Dynamic-Logical perspective leads to a better and deeper understanding of the "non-classicality" of quantum behavior than any perspective based on static Propositional Logic. (shrink)

We present a complete, decidable logic for reasoning about a notion of completely trustworthy evidence and its relations to justifiable belief and knowledge, as well as to their explicit justifications. This logic makes use of a number of evidence-related notions such as availability, admissibility, and “goodness” of a piece of evidence, and is based on an innovative modification of the Fitting semantics for Artemovʼs Justification Logic designed to preempt Gettier-type counterexamples. We combine this with ideas from belief revision and awareness (...) logics to provide an account for explicitly justified knowledge based on conclusive evidence that addresses the problem of omniscience. (shrink)

Essays appraising the contemporary relevance of am kara for inter-religious dialogue and human rights as well as revised assessments of am kara s understanding of divine grace, the role of the gods, Buddhism, am kara s relation to later Advaita, and the unity of the Self.

We formalise a notion of dynamic rationality in terms of a logic of conditional beliefs on (doxastic) plausibility models. Similarly to other epistemic statements (e.g. negations of Moore sentences and of Muddy Children announcements), dynamic rationality changes its meaning after every act of learning, and it may become true after players learn it is false. Applying this to extensive games, we “simulate” the play of a game as a succession of dynamic updates of the original plausibility model: the epistemic situation (...) when a given node is reached can be thought of as the result of a joint act of learning (via public announcements) that the node is reached. We then use the notion of “stable belief”, i.e. belief that is preserved during the play of the game, in order to give an epistemic condition for backward induction: rationality and common knowledge of stable belief in rationality. This condition is weaker than Aumann’s and compatible with the implicit assumptions (the “epistemic openness of the future”) underlying Stalnaker’s criticism of Aumann’s proof. The “dynamic” nature of our concept of rationality explains why our condition avoids the apparent circularity of the “backward induction paradox”: it is consistent to (continue to) believe in a player’s rationality after updating with his irrationality. (shrink)

We propose a new topological semantics for evidence, evidence-based justifications, belief, and knowledge. Resting on the assumption that an agent’s rational belief is based on the available evidence, we try to unveil the concrete relationship between an agent’s evidence, belief, and knowledge via a rich formal framework afforded by topologically interpreted modal logics. We prove soundness, completeness, decidability, and the finite model property for the associated logics, and apply this setting to analyze key epistemological issues such as “no false lemma” (...) Gettier examples, misleading defeaters, undefeated justification versus undefeated belief, as well as the defeasibility theories of knowledge. (shrink)

Nombreux sont les versets coraniques qui insistent sur la toute-puissance de Dieu : en maître absolu du Bien et du Mal, il fait ce que bon lui semble, égarant et sauvant qui II veut. Pris au pied de la lettre, ces versets ont inspiré une vision déterministe et fataliste dé l'homme et du monde qui exclut toute possibilité de fonder une éthique rationnelle : le bien et le mal sont entièrement déterminés par la seule volonté de Dieu et l'islam se (...) résume alors à une soumission aveugle aux décrets divins. Tenue pour responsable de l'ankylose de la pensée musulmane, voire des dérives obscurantistes de l'islamisme radical, cette position, qui résulte du triomphe de l'as'arisme dans le sunnisme postclassique, est de nos jours sévèrement critiquée par des théologiens soucieux de promouvoir un islam éclairé. Ceux-ci renouent souvent avec des doctrines mu'tazilites visant à atténuer, d'une façon ou d'une autre, la puissance divine et à reconnaître en Dieu une certaine « impuissance », afin de créer un espace pour l'homme. L'article retrace l'historique de ce débat, qui remonte aux origines mêmes de la théologie musulmane. Many verses in the Koran insist on God's omnipotence: as the absolute Master of Good and Evil, He does whatever he likes, condemning or saving whomever He decides. Understood literally, those verses have inspired a deterministic and fatalistic vision of man and the world, one which excludes any possibility of grounding a rational ethics. Both Good and Evil are totally determined by the will of God alone, and Islam may be summed up as a blind submission to divine decrees. This position, which results from the triumph of as'arism in post-classical sunnism, has been held responsible for the stagnation of Muslim thought, indeed for the obscurantist excesses of radical Islamism and is today severely criticized by some theologians concerned to promote an enlightened Islam. These scholars have often revived mu'tazilist doctrines whose aim is to weaken one way or another, notions of divine power and, by recognizing in God a certain « powerlessness », create a space for human action. This paper retraces the history of this debate which dates back to the very origins of the Muslim theology. (shrink)

We formalise a notion of dynamic rationality in terms of a logic of conditional beliefs on plausibility models. Similarly to other epistemic statements, dynamic rationality changes its meaning after every act of learning, and it may become true after players learn it is false. Applying this to extensive games, we "simulate" the play of a game as a succession of dynamic updates of the original plausibility model: the epistemic situation when a given node is reached can be thought of as (...) the result of a joint act of learning that the node is reached. We then use the notion of "stable belief, i.e. belief that is preserved during the play of the game, in order to give an epistemic condition for backward induction: rationality and common knowledge of stable belief in rationality. This condition is weaker than Aumann's and compatible with the implicit assumptions underlying Stalnaker's criticism of Aumann's proof. The "dynamic" nature of our concept of rationality explains why our condition avoids the apparent circularity of the "backward induction paradox": it is consistent to believe in a player's rationality after updating with his irrationality. (shrink)

S. Thomas d'Aquin consacre la Quaestio 73 de la première partie de la Summa Theologiae aux problèmes classiques soulevés par le récit biblique de l'hexaméron: l'achèvement des œuvres divines doit-il être attribué au septième jour? Dieu s'est-Il alors reposé de toute son œuvre? La bénédiction et la sanctification sont-elles dues au septième jour?

What triggers the act of creating? What role do sensory cues, environmental factors, and interdisciplinary exchanges play in this? The semiotic theories of Jacob von Uexküll, a Baltic German biologist, served as an important starting point in addressing these questions. In 1934 he proposed the concept of the Umwelt as a means to assess the behaviour of humans and animals, their realm of experience, and capacity to act. An investigation into the complexity of these Umwelten, from the natural world to?inner (...) worlds? and?time worlds?, is carried out by theorists, artists, and architects such as Andrés Jaque, Esther Venrooy, Bart Decroos, Isolde Vanhee, Joseph Kohlmaier, and more. (shrink)

Nombreux sont les versets coraniques qui insistent sur la toute‑puissance de Dieu : en maître absolu du Bien et du Mal, il fait ce que bon lui semble, égarant et sauvant qui Il veut. Pris au pied de la lettre, ces versets ont inspiré une vision déterministe et fataliste de l’homme et du monde qui exclut toute possibilité de fonder une éthique rationnelle : le bien et le mal sont entièrement déterminés par la seule volonté de Dieu et l’islam se (...) résume alors à une soumission aveugle aux décrets divins. Tenue pour responsable de l’ankylose de la pensée musulmane, voire des dérives obscurantistes de l’islamisme radical, cette position, qui résulte du triomphe de l’as’arisme dans le sunnisme postclassique, est de nos jours sévèrement critiquée par des théologiens soucieux de promouvoir un islam éclairé. Ceux‑ci renouent souvent avec des doctrines mu’tazilites visant à atténuer, d’une façon ou d’une autre, la puissance divine et à reconnaître en Dieu une certaine « impuissance », afin de créer un espace pour l’homme. L’article retrace l’historique de ce débat, qui remonte aux origines mêmes de la théologie musulmane.Many verses in the Koran insist on God’s omnipotence: as the absolute Master of Good and Evil, He does whatever he likes, condemning or saving whomever He decides. Understood literally, those verses have inspired a deterministic and fatalistic vision of man and the world, one which excludes any possibility of grounding a rational ethics. Both Good and Evil are totally determined by the will of God alone, and Islam may be summed up as a blind submission to divine decrees. This position, which results from the triumph of as’arism in post‑classical sunnism, has been held responsible for the stagnation of Muslim thought, indeed for the obscurantist excesses of radical Islamism and is today severely criticized by some theologians concerned to promote an enlightened Islam. These scholars have often revived mu’tazilist doctrines whose aim is to weaken one way or another, notions of divine power and, by recognizing in God a certain « powerlessness », create a space for human action. This paper retraces the history of this debate which dates back to the very origins of the Muslim theology. (shrink)

We present a semantic analysis of the Ramsey test, pointing out its deep underlying flaw: the tension between the “static” nature of AGM revision (which was originally tailored for revision of only purely ontic beliefs, and can be applied to higher-order beliefs only if given a “backwards-looking” interpretation) and the fact that, semantically speaking, any Ramsey conditional must be a modal operator (more precisely, a dynamic-epistemic one). Thus, a belief about a Ramsey conditional is in fact a higher-order belief, hence (...) the AGM revision postulates are not applicable to it, except in their “backwards-looking” interpretation. But that interpretation is consistent only with a restricted (weak) version of Ramsey’s test (in-applicable to already revised theories). The solution out of the conundrum is twofold: either accept only the weak Ramsey test; or replace the AGM revision operator ∗ by a truly “dynamic” revision operator ⊗, which will not satisfy the AGM axioms, but will do something better: it will “keep up with reality”, correctly describing revision with higher-order beliefs. (shrink)

This book illustrates the program of Logical-Informational Dynamics. Rational agents exploit the information available in the world in delicate ways, adopt a wide range of epistemic attitudes, and in that process, constantly change the world itself. Logical-Informational Dynamics is about logical systems putting such activities at center stage, focusing on the events by which we acquire information and change attitudes. Its contributions show many current logics of information and change at work, often in multi-agent settings where social behavior is essential, (...) and often stressing Johan van Benthem's pioneering work in establishing this program. However, this is not a Festschrift, but a rich tapestry for a field with a wealth of strands of its own. The reader will see the state of the art in such topics as information update, belief change, preference, learning over time, and strategic interaction in games. Moreover, no tight boundary has been enforced, and some chapters add more general mathematical or philosophical foundations or links to current trends in computer science. The theme of this book lies at the interface of many disciplines. Logic is the main methodology, but the various chapters cross easily between mathematics, computer science, philosophy, linguistics, cognitive and social sciences, while also ranging from pure theory to empirical work. Accordingly, the authors of this book represent a wide variety of original thinkers from different research communities. And their interconnected themes challenge at the same time how we think of logic, philosophy and computation. Thus, very much in line with van Benthem's work over many decades, the volume shows how all these disciplines form a natural unity in the perspective of dynamic logicians (broadly conceived) exploring their new themes today. And at the same time, in doing so, it offers a broader conception of logic with a certain grandeur, moving its horizons beyond the traditional study of consequence relations. (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)

Stalnaker, 169–199 2006) introduced a combined epistemic-doxastic logic that can formally express a strong concept of belief, a concept of belief as ‘subjective certainty’. In this paper, we provide a topological semantics for belief, in particular, for Stalnaker’s notion of belief defined as ‘epistemic possibility of knowledge’, in terms of the closure of the interior operator on extremally disconnected spaces. This semantics extends the standard topological interpretation of knowledge with a new topological semantics for belief. We prove that the belief (...) logic KD45 is sound and complete with respect to the class of extremally disconnected spaces and we compare our approach to a different topological setting in which belief is interpreted in terms of the derived set operator. We also study belief revision as well as belief dynamics by providing a topological semantics for conditional belief and belief update modalities, respectively. Our setting based on extremally disconnected spaces, however, encounters problems when extended with dynamic updates. We then propose a solution consisting in interpreting belief in a similar way based on hereditarily extremally disconnected spaces, and axiomatize the belief logic of hereditarily extremally disconnected spaces. Finally, we provide a complete axiomatization of the logic of conditional belief and knowledge, as well as a complete axiomatization of the corresponding dynamic logic. (shrink)

Scholars increasingly point toward schools as meaningful contexts in which to provide psychosocial care for refugee children. Collaborative mental health care in school forms a particular practice of school-based mental health care provision. Developed in Canada and inspired by systemic intervention approaches, collaborative mental health care in schools involves the formation of an interdisciplinary care network, in which mental health care providers and school partners collaborate with each other and the refugee family in a joint assessment of child development and (...) mental health, as well as joint intervention planning and provision. It aims to move away from an individual perspective on refugee children’s development, toward an engagement with refugee families’ perspectives on their migration histories, cultural background and social condition in shaping assessment and intervention, as such fostering refugee empowerment, equality, and participation in the host society. Relating to the first stage of van Yperen’s four-stage model for establishing evidence-based youth care, this article aims to engage in an initial exploration of the effectiveness of a developing school-based collaborative mental health care practice in Leuven, Belgium. First, we propose a detailed description, co-developed through reflection on case documents, written process reflections, intervision, an initial identification of intervention themes, and articulating interconnections with scholarly literature on transcultural and systemic refugee trauma care. Second, we engage in an in-depth exploration of processes and working mechanisms, obtained through co-constructed clinical case analysis of case work collected through our practice in schools in Leuven, Belgium. Our descriptive analysis indicates the role of central processes that may operate as working mechanisms in school-based collaborative mental health care and points to how collaborative mental health care may mobilize the school and the family-school interaction as a vehicle of restoring safety and stability in the aftermath of cumulative traumatization. Our analysis furthermore forms an important starting point for reflections on future research opportunities, and central clinical dynamics touching upon power disparities and low-threshold access to mental health care for refugee families. (shrink)

In this paper, we investigate the social herding phenomenon known as informational cascades, in which sequential inter-agent communication might lead to epistemic failures at group level, despite availability of information that should be sufficient to track the truth. We model an example of a cascade, and check the correctness of the individual reasoning of each agent involved, using two alternative logical settings: an existing probabilistic dynamic epistemic logic, and our own novel logic for counting evidence. Based on this analysis, we (...) conclude that cascades are not only likely to occur but are sometimes unavoidable by "rational" means: in some situations, the group’s inability to track the truth is the direct consequence of each agent’s rational attempt at individual truth-tracking. Moreover, our analysis shows that this is even so when rationality includes unbounded higher-order reasoning powers, as well as when it includes simpler, non-Bayesian forms of heuristic reasoning. (shrink)