After a number of decades of research into the dynamics of rational belief, the belief revision theory community remains split on the appropriate handling of sequences of changes in view, the issue of so-called iterated revision. It has long been suggested that the matter is at least partly settled by facts pertaining to the results of various single revisions of one’s initial state of belief. Recent work has pushed this thesis further, offering various strong principles that ultimately result in a (...) wholesale reduction of iterated to one-shot revision. The present paper offers grounds to hold that these principles should be significantly weakened and that the reductionist thesis should ultimately be rejected. Furthermore, the considerations provided suggest a close connection between the logic of iterated belief change and the logic of evidential relevance. (shrink)

The field of iterated belief change has focused mainly on revision, with the other main operator of AGM belief change theory, i.e. contraction, receiving relatively little attention. In this paper we extend the Harper Identity from single-step change to define iterated contraction in terms of iterated revision. Specifically, just as the Harper Identity provides a recipe for defining the belief set resulting from contracting A in terms of (i) the initial belief set and (ii) the belief set resulting from revision (...) by ¬A, we look at ways to define the plausibility ordering over worlds resulting from contracting A in terms of (iii) the initial plausibility ordering, and (iv) the plausibility ordering resulting from revision by ¬A. After noting that the most straightforward such extension leads to a trivialisation of the space of permissible orderings, we provide a family of operators for combining plausibility orderings that avoid such a result. These operators are characterised in our domain of interest by a pair of intuitively compelling properties, which turn out to enable the derivation of a number of iterated contraction postulates from postulates for iterated revision. We finish by observing that a salient member of this family allows for the derivation of counterparts for contraction of some well known iterated revision operators, as well as for defining new iterated contraction operators. (shrink)

Darwiche and Pearl’s seminal 1997 article outlined a number of baseline principles for a logic of iterated belief revision. These principles, the DP postulates, have been supplemented in a number of alternative ways. Most suggestions have resulted in a form of ‘reductionism’ that identifies belief states with orderings of worlds. However, this position has recently been criticised as being unacceptably strong. Other proposals, such as the popular principle (P), aka ‘Independence’, characteristic of ‘admissible’ operators, remain commendably more modest. In this (...) paper, we supplement the DP postulates and (P) with a number of novel conditions. While the DP postulates constrain the relation between a prior and a posterior conditional belief set, our new principles notably govern the relation between two posterior conditional belief sets obtained from a common prior by different revisions. We show that operators from the resulting family, which subsumes both lexicographic and restrained revision, can be represented as relating belief states associated with a ‘proper ordinal interval’ (POI) assignment, a structure more fine-grained than a simple ordering of worlds. We close the paper by noting that these operators satisfy iterated versions of many AGM era postulates, including Superexpansion, that are not sound for admissible operators in general. (shrink)

Discussions of the issue of iterated belief revision are commonly accompanied by the presentation of three “concrete” operators: natural, restrained and lexicographic. This raises a natural question: What is so distinctive about these three particular methods? Indeed, the common axiomatic ground for work on iterated revision, the AGM and Darwiche-Pearl postulates, leaves open a whole range of alternative proposals. In this paper, we show that it is satisfaction of an additional principle of “Independence of Irrelevant Alternatives”, inspired by the literature (...) on Social Choice, that unites and sets apart our three “elementary” revision operators. A parallel treatment of iterated belief contraction is also given, yielding a family of elementary contraction operators that includes, besides the well-known “conservative” and “moderate” operators, a new contraction operator that is related to restrained revision. (shrink)

The United Nations' designation of 1979 as the International Year of the Child marked the first global effort undertaken to heighten awareness of the special needs of children. Activities initiated during this special year were designed to promote purposive and collaborative actions for the benefit of children throughout the world. Michigan State University's celebration of the International Year of the Child was held from Septem ber 1979 through June 1980. A variety of activities focused attention on the multiplicity of factors (...) affecting the welfare of today's children as well as the children of the future. Many people involved with the university were concerned that benefits to children continue beyond the official time allocated to the celebration. The series Child Nurturance is one response to this concern. The first five volumes of Child Nurturance reflect directly the activities held on the Michigan State University campus and consist of original contributions from guest speakers and invited contributors. Subsequent biennial volumes will present original contributions from individuals representing such fields as anthropology, biology, education, human ecology, psychology, philosophy, sociology, and medicine. We hope the material presented in these volumes will promote greater understanding of children and encourage interdisciplinary inquiry into the individual, family, societal and cultural variables which influence their welfare and development. We would. like to express both our thanks and our admiration for who not only typed the camera-ready copy for each of Margaret Burritt the volumes, but also served as general manager of the entire project. (shrink)

Recent work has considered the problem of extending to the case of iterated belief change the so-called `Harper Identity' (HI), which defines single-shot contraction in terms of single-shot revision. The present paper considers the prospects of providing a similar extension of the Levi Identity (LI), in which the direction of definition runs the other way. We restrict our attention here to the three classic iterated revision operators--natural, restrained and lexicographic, for which we provide here the first collective characterisation in the (...) literature, under the appellation of `elementary' operators. We consider two prima facie plausible ways of extending (LI). The first proposal involves the use of the rational closure operator to offer a `reductive' account of iterated revision in terms of iterated contraction. The second, which doesn't commit to reductionism, was put forward some years ago by Nayak et al. We establish that, for elementary revision operators and under mild assumptions regarding contraction, Nayak's proposal is equivalent to a new set of postulates formalising the claim that contraction by ¬A should be considered to be a kind of `mild' revision by A. We then show that these, in turn, under slightly weaker assumptions, jointly amount to the conjunction of a pair of constraints on the extension of (HI) that were recently proposed in the literature. Finally, we consider the consequences of endorsing both suggestions and show that this would yield an identification of rational revision with natural revision. We close the paper by discussing the general prospects for defining iterated revision in terms of iterated contraction. (shrink)

Zen Masters of China presents more than 300 traditional Zen stories and koans, far more than any other collection. Retelling them in their proper place in Zen's historical journey, it also tells a larger story: how, in taking the first step east from India to China, Buddhism began to be Zen. The stories of Zen are unlike any other writing, religious or otherwise. Used for centuries by Zen teachers as aids to bring about or deepen the experience of awakening, they (...) have a freshness that goes way beyond religious practice and a mystery and authenticity that appeal to a wide range of readers. The author himself was drawn to Zen through the stories and has been collecting them for forty years. He began this book because he was curious about the relationships between the people you read about in the stories: they are historical figures, masters and students in Zen's long passage from India to China and on to Japan. He realized that, placed in chronological order, the stories tell the story of Zen itself, how it traveled from West to East but also how it was transformed in that journey, from an Indian practice to something different in China (Ch'an) and then more different still in Japan (Zen). The fact that its transmission was so human, from teacher to student in a long chain from West to East, meant that the cultures it passed through inevitably changed it. Zen Masters of China is first and foremost a collection of mind-bending Zen stories and their wisdom. More than that, without academic pretensions or baggage, it recounts the genealogy of Zen Buddhism in China and, through the stories themselves, illuminates how Zen became what it is today. (shrink)

This topically organized, interdisciplinary anthology provides competing perspective on the claim that western culture faces a moral crisis. Using clearly written, accessible essays by well-known authors in philosophy, the social sciences, and the humanities, the book introduces students to a variety of perspectives on the current cultural debate about values that percolates beneath the surface of most of our social and political controversies.

The United States leads the world in incarceration, and the United Kingdom is persistently one of the European countries with the highest per capita rates of imprisonment. Yet despite its increasing visibility as a social issue, mass incarceration - and its inconsistency with core democratic ideals - rarely surfaces in contemporary Anglo-American political theory. Democratic Theory and Mass Incarceration seeks to overcome this puzzling disconnect by deepening the dialogue between democratic theory and punishment policy. This collection of original essays initiates (...) a multi-disciplinary discussion among philosophers, political theorists, and criminologists regarding ways in which contemporary democratic theory might begin to think beyond mass incarceration. Rather than viewing punishment as a natural reaction to crime and imprisonment as a sensible outgrowth of this reaction, the volume argues that crime and punishment are institutions that reveal unmet demands for public oversight and democratic influence. Chapters explore theoretical paths towards de-carceration and alternatives to prison, suggest ways in which democratic theory can strengthen recent reform movements, and offer creative alternatives to mass incarceration. Democratic Theory and Mass Incarceration offers guideposts for critical thinking about incarceration, examining ways to rebuild crime control institutions and create a healthier, more just society. (shrink)

This anthology is remarkable not only for the selections themselves, among which the Schelling and the Heidegger essays were translated especially for this volume, but also for the editors' general introduction and the introductory essays for each selection, which make this volume an invaluable aid to the study of the powerful, recurrent ideas concerning art, beauty, critical method, and the nature of representation. Because this collection makes clear the ways in which the philosophy of art relates to and is part (...) of general philosophical positions, it will be an essential sourcebook to students of philosophy, art history, and literary criticism. (shrink)

A substantial amount of recent work in natural language generation has focused on the generation of ‘‘one-shot’’ referring expressions whose only aim is to identify a target referent. Dale and Reiter's Incremental Algorithm (IA) is often thought to be the best algorithm for maximizing the similarity to referring expressions produced by people. We test this hypothesis by eliciting referring expressions from human subjects and computing the similarity between the expressions elicited and the ones generated by algorithms. It turns out that (...) the success of the IA depends substantially on the ‘‘preference order’’ (PO) employed by the IA, particularly in complex domains. While some POs cause the IA to produce referring expressions that are very similar to expressions produced by human subjects, others cause the IA to perform worse than its main competitors; moreover, it turns out to be difficult to predict the success of a PO on the basis of existing psycholinguistic findings or frequencies in corpora. We also examine the computational complexity of the algorithms in question and argue that there are no compelling reasons for preferring the IA over some of its main competitors on these grounds. We conclude that future research on the generation of referring expressions should explore alternatives to the IA, focusing on algorithms, inspired by the Greedy Algorithm, which do not work with a fixed PO. (shrink)

A substantial amount of recent work in natural language generation has focused on the generation of ‘‘one‐shot’’ referring expressions whose only aim is to identify a target referent. Dale and Reiter's Incremental Algorithm (IA) is often thought to be the best algorithm for maximizing the similarity to referring expressions produced by people. We test this hypothesis by eliciting referring expressions from human subjects and computing the similarity between the expressions elicited and the ones generated by algorithms. It turns out that (...) the success of the IA depends substantially on the ‘‘preference order’’ (PO) employed by the IA, particularly in complex domains. While some POs cause the IA to produce referring expressions that are very similar to expressions produced by human subjects, others cause the IA to perform worse than its main competitors; moreover, it turns out to be difficult to predict the success of a PO on the basis of existing psycholinguistic findings or frequencies in corpora. We also examine the computational complexity of the algorithms in question and argue that there are no compelling reasons for preferring the IA over some of its main competitors on these grounds. We conclude that future research on the generation of referring expressions should explore alternatives to the IA, focusing on algorithms, inspired by the Greedy Algorithm, which do not work with a fixed PO. (shrink)