Ranking theory is one of the salient formal representations of doxastic states. It differs from others in being able to represent belief in a proposition (= taking it to be true), to also represent degrees of belief (i.e. beliefs as more or less firm), and thus to generally account for the dynamics of these beliefs. It does so on the basis of fundamental and compelling rationality postulates and is hence one way of explicating the rational structure of doxastic states. Thereby (...) it provides foundations for accounts of defeasible or nonmonotonic reasoning. It has widespread applications in philosophy, it proves to be most useful in Artificial Intelligence, and it has started to find applications as a model of reasoning in psychology. (shrink)

There are several approaches implementing reasoning based on conditional knowledge bases, one of the most popular being System Z (Pearl, Proceedings of the 3rd conference on theoretical aspects of reasoning about knowledge, TARK ’90, Morgan Kaufmann Publishers Inc., San Francisco, CA, USA, pp. 121–135, 1990). We look at ranking functions (Spohn, The Laws of Belief: Ranking Theory and Its Philosophical Applications, Oxford University Press, Oxford, 2012) in general, conditional structures and c-representations (Kern-Isberner, Conditionals in Nonmonotonic Reasoning and Belief (...) Revision: Considering Conditionals as Agents, vol. 2087 of LNCS, Springer, Berlin, 2001) in order to examine the reasoning strength of the different approaches by learning which of the known calculi of nonmonotonic reasoning (System P and R) and Direct Inference are applicable to these inference relations. Furthermore we use the recently proposed Enforcement-postulate (Kern-Isberner and Krümpelmann, Proceedings of the 22nd international joint conference on artificial intelligence, vol. 2, IJCAI’11, AAAI Press, pp. 937–942, 2011) to show dependencies between these approaches. (shrink)

This book covers lymphoproliferative disorders in patients with congenital or acquired immunodeficiencies. Acquired immunodeficiencies are caused by infections with the human immunodeficiency virus or arise following immunosuppressive therapy administered after organ transplantation or to treat connective tissue diseases such as rheumatoid arthritis. It was recently discovered that various diseases or therapeutic modalities that induce a state of immunosuppression may cause virally driven lymphoproliferations. This book summarizes for the first time this group of immunodeficiency-associated lymphoproliferations.

Conditionals are most important objects in knowledge representation, commonsense reasoning and belief revision. Due to their non-classical nature, however, they are not easily dealt with. This paper presents a new approach to conditionals, which is apt to capture their dynamic power particularly well. We show how this approach can be applied to represent conditional knowledge inductively, and to guide revisions of epistemic states by sets of beliefs. In particular, we generalize system-Z* as an appropriate counterpart to maximum entropy-representations in a (...) semi-quantitative setting, and provide a theoretical justification to make its basic ideas usable also for belief revision. (shrink)

The idea of preserving conditional beliefs emerged recently as a new paradigm apt to guide the revision of epistemic states. Conditionals are substantially different from propositional beliefs and need specific treatment. In this paper, we present a new approach to conditionals, capturing particularly well their dynamic part as revision policies. We thoroughly axiomatize a principle of conditional preservation as an indifference property with respect to conditional structures of worlds. This principle is developed in a semi-quantitative setting, so as to reveal (...) its fundamental meaning for belief revision in quantitative as well as in qualitative frameworks. In fact, it is shown to cover other proposed approaches to conditional preservation. (shrink)

The idea of preserving conditional beliefs emerged recently as a new paradigm apt to guide the revision of epistemic states. Conditionals are substantially different from propositional (or, more generally, factual) beliefs and need specific treatment. In this paper, we present a new approach to conditionals, capturing particularly well their dynamic part as revision policies. We thoroughly axiomatize a principle of conditional preservation as an indifference property with respect to conditional structures of worlds. This principle is developed in a semi-quantitative setting, (...) so as to reveal its fundamental meaning for belief revision in quantitative as well as in qualitative frameworks. In fact, it is shown to cover other proposed approaches to conditional preservation. (shrink)

This special issue “Inferences and Information Processing in a Conditional Framework“ is dedicated to conditionals as central objects for inferencing and information processing. It presents selected revised papers of the Workshop on Conditionals, Information, and Inference, CII'04, held in Ulm, Germany, co-located with the German national conference on AI, KI'2004.Conditional statements If A then B carry a very special kind of information that can not be captured by interpreting them as material implications. Roughly speaking, the premise, A, provides a context (...) in which it seems plausible to conclude B. So, each conditional can be seen as establishing a tight but flexible link between premise and conclusion, making up a unique piece of information. This link can and has been used successfully for knowledge representation, in particular, for nonclassical inferences and revising beliefs.It is just this generic, dynamic nature of conditionals that makes them most fascinating objects which are, however, difficult to control. But it seems that the problems one typically encounters when using conditionals for reasoning, mostly occur due to the narrowness of thinking strictly along classical lines that we have been getting used to. Classical logic has imposed a rigidity on human thinking that helped a lot making reasoning formal, precise, and clear. Conditionals, on the other hand, open up dimensions beyond classical theories, leaving room for plausibility, uncertainty, intuition, and commonsense reasoning. Philosophers and logicians have been discussing their logical nature since the …. (shrink)

In this article we explore multiple change operators, i.e., operators in which the epistemic input is a set of sentences instead of a single sentence. We propose two types of change: prioritized change, in which the input set is fully accepted, and symmetric change, where both the epistemic state and the epistemic input are equally treated. In both kinds of operators we propose a set of postulates and we present different constructions: kernel changes and partial meet changes.

We present different constructions for nonprioritized belief revision, that is, belief changes in which the input sentences are not always accepted. First, we present the concept of explanation in a deductive way. Second, we define multiple revision operators with respect to sets of sentences (representing explanations), giving representation theorems. Finally, we relate the formulated operators with argumentative systems and default reasoning frameworks.

The knowledge representation and reasoning of both humans and artificial systems often involves conditionals. A conditional connects a consequence which holds given a precondition. It can be easily recognized in natural languages with certain key words, like “if” in English. A vast amount of literature in both fields, both artificial intelligence and psychology, deals with the questions of how such conditionals can be best represented and how these conditionals can model human reasoning. On the other hand, findings in the psychology (...) of reasoning, such as those in the Suppression Task, have led to a paradigm shift from the monotonicity assumptions in human inferences towards nonmonotonic reasoning. Nonmonotonic reasoning is sensitive for information change, that is, inferences are drawn cautiously such that retraction of previous information is not required with the addition of new information. While many formalisms of nonmonotonic reasoning have been proposed in the field of Artificial Intelligence, their capability to model properties of human reasoning has not yet been extensively investigated. In this paper, we analyzed systematically from both a formal and an empirical perspective the power of formal nonmonotonic systems to model possible explicit defeaters, as in the Suppression Task, and more implicit conditional rules that trigger nonmonotonic reasoning by the keywords in such rules. The results indicated that the classical evaluation for the correctness of inferences has to be extended in the three major aspects regarding the inference system, the knowledge base, and possible assumed exceptions for the rule. (shrink)

There are numerous formal systems that allow inference of new conditionals based on a conditional knowledge base. Many of these systems have been analysed theoretically and some have been tested against human reasoning in psychological studies, but experiments evaluating the performance of such systems are rare. In this article, we extend the experiments in [19] in order to evaluate the inferential properties of c-representations in comparison to the well-known Systems P and Z. Since it is known that System Z and (...) c-representations mainly differ in the sorts of inheritance inferences they allow, we discuss subclass inheritance and present experimental data for this type of inference in particular. (shrink)

We propose a revision operator on a stratified belief base, i.e., a belief base that stores beliefs in different strata corresponding to the value an agent assigns to these beliefs. Furthermore, the operator will be defined as to perform the revision in such a way that information is never lost upon revision but stored in a stratum or layer containing information perceived as having a lower value. In this manner, if the revision of one layer leads to the rejection of (...) some information to maintain consistency, instead of being withdrawn it will be kept and introduced in a different layer with lower value. Throughout this development we will follow the principle of minimal change, being one of the important principles proposed in belief change theory, particularly emphasized in the AGM model. Regarding the reasoning part from the stratified belief base, the agent will obtain the inferences using an argumentative formalism. Thus, the argumentation framework will decide which information prevails when sentences of different layers are used for entailing conflicting beliefs. We will also illustrate how inferences are changed and how the status of arguments can be modified after a revision process. (shrink)

This article aims to achieve two goals: to show that probability is not the only way of dealing with uncertainty ; and to provide evidence that logic-based methods can well support reasoning with uncertainty. For the latter claim, two paradigmatic examples are presented: logic programming with Kleene semantics for modelling reasoning from information in a discourse, to an interpretation of the state of affairs of the intended model, and a neural-symbolic implementation of input/output logic for dealing with uncertainty in dynamic (...) normative contexts. (shrink)

Alternative food networks, such as farmers’ markets and community-supported agricultural and fishery programs, often struggle to reach beyond a consumer base that is predominantly white and affluent. This case study explores seven inclusion strategies deployed by a community-supported fishery program (Fishadelphia, in Philadelphia, PA, USA) including discounting prices, accepting payment in multiple forms and schedules, offering a range of product types, communicating and recruiting through a variety of media (especially in person), and choosing local institutions and people of color (POC) (...) as pickup location hosts. Our analysis indicated that all of these strategies were associated with increased participation of customers of color and/or customers without a college degree. For Asian customers, accepting cash, offering whole fish, recruiting in-person, and POC-hosted pickup locations were key factors. For Black customers, discounted price, accepting cash, offering fillets, and communicating through means other than email were most important. Discounted price and communicating through means other than email were most important for customers without a college degree. Payment method, payment schedule and communication method were highly correlated with other strategies; we suggest that these strategies work in synergy to make the program attractive and feasible to these customers. We consider how Fishadelphia’s inclusion efforts have benefitted from both tactical approaches (i.e., programmatic features) and a structural approaches (i.e., the people and places represented within the project), and suggest that elements of both tactical and structural inclusion can be applied in other contexts. This work is crucial for increasing food access, and underscores the importance of relationships in recruiting diverse customers. (shrink)

Dans ce livre très original, Markus Gabriel avance une théorie du soi humain qui surmonte les blocages inhérents aux positions standards en philosophie de l’esprit contemporaine. Son point de vue, le néo-existentialisme, est intégralement antinaturaliste, en ce sens qu’il rejette toute théorie selon laquelle l’ensemble de nos meilleures connaissances scientifiques naturelles serait pleinement capable de rendre compte de l’esprit humain. L’auteur montre plutôt que l’esprit humain consiste en une prolifération ouverte de vocabulaires mentalistes. Leur rôle dans la forme de vie (...) humaine consiste à rendre compte du fait que l’être humain ne se fond pas simplement dans la nature inanimée et le reste du règne animal. Les humains s’appuient sur un autoportrait qui les situe dans un contexte aussi large que possible au sein de l’univers. Ce qui distingue cet autoportrait de notre connaissance de la réalité naturelle, c’est que nous changeons en vertu de nos croyances, vraies ou fausses, au sujet de nous-mêmes. (shrink)

In this highly original book, Markus Gabriel presents 'Neo-Existentialism', an anti-naturalist view that holds that human mindedness consists in an open-ended proliferation of mentalistic vocabularies. Challenged by Charles Taylor, Andrea Kern and Jocelyn Benoist, Gabriel deftly refutes naturalism's metaphysical claim to epistemic exclusiveness.

Bd. 1. A-B -- Bd. 2. C-F -- Bd. 3. G-Inn -- Bd. 4. Ins-Loc.

Financing Public Schools moves beyond the basics of financing public elementary and secondary education to explore the historical, philosophical, and legal underpinnings of a viable public school system. Coverage includes the operational aspects of school finance, including issues regarding teacher salaries and pensions, budgeting for instructional programs, school transportation, and risk management. Diving deeper than other school finance books, the authors explore the political framework within which the schools must function, discuss the privatization of education and its effects on public (...) schools, offer perspectives regarding education as an investment in human capital, and expertly explain complex financial and economic issues. This comprehensive text provides the tools to apply the many and varied fiscal concepts and practices that are essential for aspiring public school administrators who aim to provide responsible stewardship for their students. (shrink)

Public reason liberalism is defined by the idea that laws and policies should be justifiable to each person who is subject to them. But what does it mean for reasons to be public or, in other words, suitable for this process of justification? In response to this question, Kevin Vallier has recently developed the traditional distinction between consensus and convergence public reason into a classification distinguishing three main approaches: shareability, accessibility and intelligibility. The goal of this paper is to defend (...) the accessibility approach by demonstrating its ability to strike an appealing middle course in terms of inclusivity between shareability and intelligibility. We first argue against Vallier that accessibility can exclude religious reasons from public justification. Second, we use scientific reasons as a case study to show that accessibility excludes considerably fewer reasons than shareability. Throughout the paper, we connect our discussion of accessibility to John Rawls’s model of public reason, so as to give substance to the accessibility approach and to further our understanding of Rawls’s influential model. (shrink)

This important collection of lectures and essays was regarded by Gabriel Marcel as the best introduction to his thought.

Für Meister Eckhart (um 1260 - um 1328) ist der Mensch als Ebenbild Gottes ein denkendes Wesen, wobei das Denken für ihn epistemologische und ontologische Relevanz hat. Diese Arbeit behandelt wesentliche Aspekte von Eckharts Denken, so seine Intellekttheorie, die theoontologische Wertung der Ichs, die Armut, die Liebe, die Zeit, das Nichts, das Glück und den Frieden.