In this paper we present a new modeling for belief revision that is what we term irrevocable. This modeling is of philosophical interest since it captures some features of suppositional reasoning, and of formal interest since it is closely connected with AGM, yet provides for iterated belief revision. The analysis is couched in terms of dynamic doxastic logic.

Since the early 1980s, logical theories of belief revision have offered formal methods for the transformation of knowledge bases or “corpora” of data and beliefs. Early models have dealt with unconditional acceptance and integration of potentially belief-contravening pieces of information into the existing corpus. More recently, models of “non-prioritized” revision were proposed that allow the agent rationally to refuse to accept the new information. This paper introduces a refined method for changing beliefs by specifying constraints on the relative (...) plausibility of propositions. Like the earlier belief revision models, the method proposed is a qualitative one, in the sense that no numbers are needed in order to specify the posterior plausibility of the new information. We use reference beliefs in order to determine the degree of entrenchment of the newly accepted piece of information. We provide two kinds of semantics for this idea, give a logical characterization of the new model, study its relation with other operations of belief revision and contraction, and discuss its intuitive strengths and weaknesses. (shrink)

Krister Segerberg proposed irrevocable belief revision, to be contrasted with standard belief revision, in a setting wherein belief of propositional formulas is modelled explicitly. This suggests that in standard belief revision is revocable: one should be able to unmake (‘revoke’) the fresh belief in the revision formula, given yet further information that contradicts it. In a dynamic epistemic logical setting for belief revision, for multiple agents, we investigate what the requirements are for revocable belief (...) revision. By this we not merely mean recovering belief in non-modal propositions, as in the recovery principle for belief contraction, but recovering belief in modal propositions: beliefs about beliefs. These requirements are almost never met, a surprising result. (shrink)

Vladimir Jankélévitch was one of the most distinctive voices in twentieth-century philosophy. In _The Bad Conscience_—published in 1933 and subsequently revised and expanded—Jankélévitch lays the foundations for his later work, _Forgiveness,_ grappling with the conditions that give rise to the moral awareness without which forgiveness would make no sense. Remorse, or “the bad conscience,” arises from the realization that the acts one has committed become irrevocable. This realization, in turn, gives rise to an awareness of moral virtues and values, (...) as well as freedom and the responsibilities freedom entails. Thus, while the majority of moral systems try to shield us from remorse, the remedy for the bad conscience lies not in repentance but in the experience of remorse itself. To this careful and sensitive English-language translation of _The Bad Conscience,_ translator Andrew Kelley has added a substantial introduction situating the work in historical and intellectual context. Notes throughout indicate differences between this and earlier editions. A thought-provoking critique of standard conceptions of moral philosophy, _The Bad Conscience_ restores this work by an important philosopher who has only recently begun to receive his due from the English-speaking world. (shrink)

David Gauthier claims that it can be rational to co-operate in a prisoner's dilemma if one has adopted a disposition constraining one's self from maximizing one's individual expected utility, i.e., a constrained maximizer disposition. But I claim cooperation cannot be both voluntary and constrained. In resolving this tension I ask what constrained maximizer dispositions might be. One possibility is that they are rationally acquired, irrevocable psychological mechanisms which determine but do not rationalize cooperation. Another possibility is that they are (...) rationally acquired preference-functions rationalizing cooperation as maximizing. I argue that if they are the first thing, then their adoption fails to make co-operation rational even if, as Gauthier also claims, actions are rational if they express rational dispositions. I then suggest that taking constrained maximizer dispositions to be things of the second sort would result in them being able to make co-operation rational, and that so-taking them therefore serves the bulk and spirit of Gauthier's larger claims, which I reconstruct accordingly. (shrink)

We present a theory of truth in fiction that improves on Lewis's [1978] ‘Analysis 2’ in two ways. First, we expand Lewis's possible worlds apparatus by adding non-normal or impossible worlds. Second, we model truth in fiction as belief revision via ideas from dynamic epistemic logic. We explain the major objections raised against Lewis's original view and show that our theory overcomes them.

A Moorean fact, in the words of the late David Lewis, is ‘one of those things that we know better than we know the premises of any philosophical argument to the contrary’. Lewis opens his seminal paper ‘Elusive Knowledge’ with the following declaration.

This paper presents 59 new studies (N = 72,310) which focus primarily on the “bat and ball problem.” It documents our attempts to understand the determinants of the erroneous intuition, our exploration of ways to stimulate reflection, and our discovery that the erroneous intuition often survives whatever further reflection can be induced. Our investigation helps inform conceptions of dual process models, as “system 1” processes often appear to override or corrupt “system 2” processes. Many choose to uphold their intuition, even (...) when directly confronted with simple arithmetic that contradicts it – especially if the intuition is approximately correct. (shrink)

A study in the logic of theory change, examining the properties of maxichoice contraction and revision operations.

In this book, Yaqub describes a simple conception of truth and shows that it yields a semantical theory that accommodates the whole range of our seemingly conflicting intuitions about truth. This conception takes the Tarskian biconditionals as correctly and completely defining the notion of truth. The semantical theory, which is called the revision theory, that emerges from this conception paints a metaphysical picture of truth as a property whose applicability is given by a revision process rather than by (...) a fixed extension. The main advantage of this revision process is its ability to explain why truth seems in many cases almost redundant, in others substantial, and yet in others paradoxical. Yaub offers a comprehensive defense of the revision theory of truth by developing consistent and adequate formal semantics for languages in which all sorts of problematic sentences can be constructed. Yaqub concludes by introducing a logic of truth that further demonstrates the adequacy of the revision theory. (shrink)

The purpose of this work is to critically assess Errol E. Harris’s process philosophy in the face of contemporary research in the special sciences. Harris devoted his life to grappling with the big questions concerning the relationships between nature, mind, and knowledge. His 70-plus year career was distinguished, his texts on the history of philosophy, philosophy of science, political philosophy, philosophy of religion, and consciousness were widely published, and yet his metaphysics has until now remained excluded from mainstream discussions. This (...) book’s contention is that Harris’s work reveals as yet unnoticed connections between theories in numerous scientific disciplines ranging from psychology to cosmology and that an examination of certain theories within these disciplines may serve to strengthen his original arguments. This work maintains that the resulting metaphysics frames a transdisciplinary paradigm shift and provides a viable solution to the hard problem of consciousness. (shrink)

It is argued in this paper that a multimodal analysis of turn-taking, one of the core areas of conversation analytic research, is needed and has to integrate gaze as one of the most central resources for allocating turns, and that new technologies are available that can provide a solid and reliable empirical foundation for this analysis. On the basis of eye-tracking data of spontaneous conversations, it is shown that gaze is the most ubiquitous next-speaker-selection technique. It can function alone or (...) enhance other techniques. I also discuss the interrelationship between the strength for sequential projection and the choice of next-speaker-selection techniques by a current speaker. The appropriate consideration of gaze leads to a revision of the turn-taking model in that it reduces the domain of self-selection and expands that of the current-speaker-selects-next sub-rule. It also has consequences for the analysis of “simultaneous starts”. (shrink)

By Belief Revision it is understood a system that logically explains the rational process of changing beliefs by taking into account a new piece of information. The most influential approach in this field of study, the AGM system, proposed by Alchourrón, Gärdenfors, and Makinson, postulates rationality criteria for different types of belief change. In this paper I shall assess the relationship between those criteria and argue for an opposition between the principles of Information Economy and Consistency. Furthermore, I shall (...) argue that Paraconsistent Belief Revision manages to minimise this friction in the best possible way. (shrink)

This collection of essays is on the relation between probabilities, especially conditional probabilities, and conditionals. It provides negative results which sharply limit the ways conditionals can be related to conditional probabilities. There are also positive ideas and results which will open up areas of research. The collection is intended to honour Ernest W. Adams, whose seminal work is largely responsible for creating this area of inquiry. As well as describing, evaluating, and applying Adams's work the contributions extend his ideas in (...) directions he may or may not have anticipated, but that he certainly inspired. In addition to a wide range of philosophers of science, the volume should interest computer scientists and linguists. (shrink)

The last section made it clear that an analysis which at first seems to fail is viable after all. It is viable if we let it depend on a partition function to be provided by the context of conversation. This analysis leaves certain traits of the partition function open. I have tried to show that this should be so. Specifying these traits as Pollock does leads to wrong predictions. And leaving them open endows counterfactuals with just the right amount of (...) variability and vagueness. (shrink)

What kind of evidence will lead people to revise their moral beliefs? Moral beliefs are often strongly held convictions, and existing research has shown that morality is rooted in emotion and socialization rather than deliberative reasoning. In addition, more general issues—such as confirmation bias—further impede coherent belief revision. Here, we explored a unique means for inducing belief revision. In two experiments, participants considered a moral dilemma in which an overwhelming majority of people judged that it was inappropriate to (...) take action to maximize utility. Their judgments contradicted a utilitarian principle they otherwise strongly endorsed. Exposure to this scenario led participants to revise their belief in the utilitarian principle, and this revision persisted over several hours. This method provides a new avenue for inducing belief revision. (shrink)

This paper recommends that experimental analysts of language development abandon for the purposes of experimental inquiry both the term "language" and the concept it designates. In support of this recommendation, the paper dis cusses the multiple meanings of "language," the proposal that "language" refers to behavior, the implicit acceptance by behavior analysts of psycholinguistic thought despite their ostensible rejection of it, and the nature of language as a subject matter. In addition, the nature of common-sense psychology, the domain of behavior (...) analysis, the formal nature of Chomskyan linguistics, and the rela tion between psychology and behavior analysis are discussed. (shrink)

Neuroethics is an emerging interdisciplinary field with unsettled boundaries. Many of the ethical issues within the purview of neuroethics could be described as resulting from the clash between the scientific perspective on concepts such as free will, personal identity, consciousness, etc., and the putatively commonsense conceptions of those terms. The assumption that undergirds the framing of the conflict between these two approaches is that advances in neuroscience, psychiatry, and psychology can be used to explain phenomena covered by commonsense concepts and (...) in some cases undermine them entirely. This book is focused on the examination of the particular relationship between developments in neuroscience and commonsense moral concepts. Common sense, I argue, has been misinterpreted as a static, either foundational or degenerative, basis of our morality, when it is an ever shifting repository of theories from many domains. Within this discussion, I focus on the application of neuroscience to human beings, i.e., the ethics of neuroscience. But I also cover issues within the purview of the neuroscience of ethics, and attempt to address the infiltration of neuroscientific knowledge into everyday parlance and the impact of that on our commonsense morality and psychology. (shrink)

In ‘belief revision’ a theory is revised with a formula φ resulting in a revised theory . Typically, is in , one has to give up belief in by a process of retraction, and φ is in . We propose to model belief revision in a dynamic epistemic logic. In this setting, we typically have an information state (pointed Kripke model) for the theory wherein the agent believes the negation of the revision formula, i.e., wherein is true. (...) The revision with φ is a program *φ that transforms this information state into a new information state. The transformation is described by a dynamic modal operator [*φ], that is interpreted as a binary relation [ [*φ] ] between information states. The next information state is computed from the current information state and the belief revision formula. If the revision is successful, the agent believes φ in the resulting state, i.e., Bφ is then true. To make this work, as information states we propose ‘doxastic epistemic models’ that represent both knowledge and degrees of belief. These are multi-modal and multi-agent Kripke models. They are constructed from preference relations for agents, and they satisfy various characterizable multi-agent frame properties. Iterated, revocable, and higher-order belief revision are all quite natural in this setting. We present, for an example, five different ways of such dynamic belief revision. One can also see that as a non-deterministic epistemic action with two alternatives, where one is preferred over the other, and there is a natural generalization to general epistemic actions with preferences. (shrink)

The paper introduces ten open problems in belief revision theory, related to the representation of the belief state, to different notions of degrees of belief, and to the nature of change operations. It is argued that these problems are all issues in philosopical logic, in the strong sense of requiring inputs from both logic and philosophy for their solution.

This paper summarizes and systematizes recent and ongoing work on non-prioritized belief change, i.e., belief revision in which the new information has no special priority due to its novelty.

A set of sentential revision operations can be generated in a select-direct way within a new framework for belief change named descriptor revision firstly introduced in Hansson [8]. In this paper, we adopt another constructive approach to these operations, based on a relation \ on sentences named believability relation. Intuitively, \ means that the subject is at least as prone to believe or accept \ as to believe or accept \. We demonstrate that so called H-believability relations and (...) basic believability relations, the second of which the is axiomatically characterized with a set of weak postulates, are faithful alternative models for two typical select-direct sentential revision operations. Then we investigate additional postulates on believability relations that correlate with properties of the generated revision operations. Finally, we show that traditional AGM revision operations can be reconstructed from a strengthened variant of the basic believability relation and there is a close connection between this relation and the standard epistemic entrenchment relation. (shrink)

Change, Choice and Inference develops logical theories that are necessary both for the understanding of adaptable human reasoning and for the design of intelligent systems. The book shows that reasoning processes - the drawing on inferences and changing one's beliefs - can be viewed as belonging to the realm of practical reason by embedding logical theories into the broader context of the theory of rational choice. The book unifies lively and significant strands of research in logic, philosophy, economics and artificial (...) intelligence. It elaborates on the relevant theories and provides a mathematically precise foundation for the thesis that large parts of theoretical reason can be subsumed under practical reason. (shrink)

A new equivalent presentation of AGM revision is introduced, in which a preference-based choice function directly selects one among the potential outcomes of the operation. This model differs from the usual presentations of AGM revision in which the choice function instead delivers a collection of sets whose intersection is the outcome. The new presentation confirms the versatility of AGM revision, but it also lends credibility to the more general model of direct choice among outcomes of which AGM (...) revision is shown here to be a special case. (shrink)

We show in this paper that the AGM postulates are too weak to ensure the rational preservation of conditional beliefs during belief revision, thus permitting improper responses to sequences of observations. We remedy this weakness by proposing four additional postulates, which are sound relative to a qualitative version of probabilistic conditioning. Contrary to the AGM framework, the proposed postulates characterize belief revision as a process which may depend on elements of an epistemic state that are not necessarily captured (...) by a belief set. We also show that a simple modification to the AGM framework can allow belief revision to be a function of epistemic states. We establish a model-based representation theorem which characterizes the proposed postulates and constrains, in turn, the way in which entrenchment orderings may be transformed under iterated belief revision. (shrink)

In a recent article in Sociology, Diane Richardson contends that rather than focusing on theorizing the specific relationship between sexuality and gender, researchers should focus on developing frameworks that capture the complex and dynamic nature of that relationship. Towards that end, Richardson proposes ‘patterned fluidities’ as a working metaphor for feminine sexuality. This article explores the potential of the metaphor as a focal point for bringing together different strands of feminist thought on heterosexuality. It discusses if and how ‘patterned fluidities’ (...) are supported by empirical evidence and how they interact with areas of thought that do not fall within the scope of Richardson’s article, namely feminist views on postmodernity. Three contemporary Greek novels are used as examples. (shrink)

In ‘belief revision’ a theory\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\cal K}$$\end{document} is revised with a formula φ resulting in a revised theory \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\cal K}\ast\varphi$$\end{document}. Typically, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\neg\varphi$$\end{document} is in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\cal K}$$\end{document}, one has to give up belief in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\neg\varphi$$\end{document} by a (...) process of retraction, and φ is in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\cal K}\ast\varphi$$\end{document}. We propose to model belief revision in a dynamic epistemic logic. In this setting, we typically have an information state (pointed Kripke model) for the theory \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\cal K}$$\end{document} wherein the agent believes the negation of the revision formula, i.e., wherein \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$B\neg\varphi$$\end{document} is true. The revision with φ is a program *φ that transforms this information state into a new information state. The transformation is described by a dynamic modal operator [*φ], that is interpreted as a binary relation [ [*φ] ] between information states. The next information state is computed from the current information state and the belief revision formula. If the revision is successful, the agent believes φ in the resulting state, i.e., Bφ is then true. To make this work, as information states we propose ‘doxastic epistemic models’ that represent both knowledge and degrees of belief. These are multi-modal and multi-agent Kripke models. They are constructed from preference relations for agents, and they satisfy various characterizable multi-agent frame properties. Iterated, revocable, and higher-order belief revision are all quite natural in this setting. We present, for an example, five different ways of such dynamic belief revision. One can also see that as a non-deterministic epistemic action with two alternatives, where one is preferred over the other, and there is a natural generalization to general epistemic actions with preferences. (shrink)

In the following paper we provide a personal definition of the existential philosophy and the existential subject. Before that we explore other historical definitions of existentialism. We were mainly interested in the relation between existentialism and nihilism, the focus of existential philosophy on the individual and the situation of the studied philosophical trend on the 1950's zeitgeist. The definition of existentialism as a form of trans-rationalism and its capacity to become a practical alternative to contemporary academic philosophy were also emphasized.

Jespersen (1860-1934:73-75) described what he called resumptive negation: “A second class [of emphatic negation] comprises what may be termed resumptive negation, the characteristic of which is that after a negative sentence has been completed, something is added in a negative form with the obvious result that the negative result is heightened. . . . In its pure form, the supplementary negative is added outside the frame of the first sentence, generally as a afterthought, as in ‘I shall never do it, (...) not under any circumstances, not on any condition, neither at home nor abroad’, etc.” Such examples have, to the best my knowledge, received no attention in the modern linguistic literature with the exception of the discussion by van der Wouden (1997) and mention (without discussion) in (Lawler 1977), plus brief comments by Klima and by McCawley (see van der Wouden) . A somewhat similar type of example (1) is known from Ross’s (1967) “Slifting” paper, where it is presented with along with extensive p.c. comments from Larry Horn; later in passim mention appears in (Horn 1989) and occasionally elsewhere. (shrink)