I propose a `stage theory’ of groups: a group is a fusion of group-stages, where a group-stage is a plurality of individuals at a world and a time. The stage theory consists of existence conditions, identity conditions, and parthood conditions for groups.

Presents Newton's unifying idea of gravitation and explains how he converted physics from a science of explanation into a general mathematical system.

I show that centered propositions—also called de se propositions, and usually modeled as sets of centered worlds—pose a serious problem for various versions of Lewis's Principal Principle. The problem, put roughly, is that in scenarios like Elga's `Sleeping Beauty' case, those principles imply that rational agents ought to have obviously irrational credences. To solve the problem, I propose a centered version of the Principal Principle. My version allows centered propositions to be objectively chancy.

In this paper, I give an argument for the view that non-fact entities – such as physical objects, abstract objects, events and so on – can ground other entities. Roughly put, the argument is as follows: those who accept this view can provide a more plausible account of the grounds of identity facts than those who deny this view.

It is a popular view thatpractical deliberation excludes foreknowledge of one's choice. Wolfgang Spohn and Isaac Levi have argued that not even a purely probabilistic self-predictionis available to thedeliberator, if one takes subjective probabilities to be conceptually linked to betting rates. It makes no sense to have a betting rate for an option, for one's willingness to bet on the option depends on the net gain from the bet, in combination with the option's antecedent utility, rather than on the (...) offered odds. And even apart from this consideration, assigning probabilities to the options among which one is choosing is futile since such probabilities could be of no possible use in choice. The paper subjects these arguments to critical examination and suggests that, appearances notwithstanding, practical deliberation need not crowd outself-prediction. (shrink)

Group judgements are often – implicitly or explicitly – influenced by their members’ individual expertise. However, given that expertise is seldom recognized fully and that some distortions may occur (bias, correlation, etc.), it is not clear that differential weighting is an epistemically advantageous strategy with respect to straight averaging. Our paper characterizes a wide set of conditions under which differential weighting outperforms straight averaging and embeds the results into the multidisciplinary group decision-making literature.

The Poetics of Psychoanalysis explores the literary aspects of the twentieth-century psychoanalytic tradition that has come to be known as British Object Relations psychoanalysis. It focuses on the writing of Klein, Sharpe, Riviere, Isaacs, Winnicott, Milner, and Bion. Giving a central place to literary and aesthetic concerns, it makes connections with particular works of literature and art. The Poetics of Psychoanalysis is aimed at literary readers, but will also be of interest to psychoanalytic practitioners.

Positing group level obligations has come under attack from concerns relating to agency as a necessary requirement for obligation bearing. Roughly stated, the worry is that since only agents can have moral obligations, and groups are not agents, groups cannot have moral obligations. The intuition behind this constraint is itself based on the ability requirement of 'ought implies can': in order for a group to have an obligation it must have the ability to perform an action, but only agents can (...) have abilities. This paper argues that from accounts of shared agency we can develop a concept of joint ability, undermining the problem of agency for group obligations. (shrink)

This book draws on fields as diverse as biochemistry, physiology, pharmacology, psychology, psychiatry, and ethology, to form a fascinating synthesis of information on the nature of fear and of panic and anxiety disorders. Dr. Marks offers both a detailed discussion of the clinical aspects of fear-related syndromes and a broad exploration of the sources and mechanisms of fear and defensive behavior. Dealing first with normal fear, he establishes a firm, scientific basis for understanding it. He then presents a thorough analysis (...) of the development, symptoms and treatment of fear-related syndromes. Phobic and obsessive-compulsive disorders are examined in detail. The book is illustrated with examples of fear and defensive behavior in other living organisms. By drawing provocative analogies between animal and human behavior, it sheds new light on the origins of fears, phobias, and obsessive-compulsive problems, as well as on their treatment by drugs and psychological means. Clinical psychologists, ethologists, and anyone interested in the mechanisms of behavior will be fascinated by this authoritative study. The text is intriguing and informative, and the bibliography of over 2,100 entries makes it an invaluable reference. (shrink)

Isaac Levi's new book develops further his pioneering work in formal epistemology, focusing on the problem of belief contraction, or how rationally to relinquish old beliefs. Levi offers the most penetrating analysis to date of this key question in epistemology, offering a completely new solution and explaining its relation to his earlier proposals. He mounts an argument in favor of the thesis that contracting a state of belief by giving up specific beliefs is to be evaluated in terms of (...) the value of the information lost by doing so. The rationale aims to be thoroughly decision theoretic. Levi spells out his goals and shows that certain types of recommendations are obtained if one seeks to promote these goals. He compares his approach to his earlier account of inductive expansion. The recommendations are for "mild contractions." These are formally the same as the "severe withdrawals" considered by Pagnucco and Rott. The rationale, however, is different. A critical part of the book concerns the elaboration of these differences. The results are relevant to accounts of the conditions under which it is legitimate to cease believing and to accounts of conditionals. Mild Contraction will be of great interest to all specialists in belief revision theory and to many students of formal epistemology, philosophy of science, and pragmatism. (shrink)

For the past fifty years anxiety over naturalism has driven debates in social theory. One side sees social science as another kind of natural science, while the other rejects the possibility of objective and explanatory knowledge. _Interpretation and Social Knowledge_ suggests a different route, offering a way forward for an antinaturalist sociology that overcomes the opposition between interpretation and explanation and uses theory to build concrete, historically specific causal explanations of social phenomena.

Evidential Decision Theory is flawed, but its flaws are not fully understood. David Lewis (1981) famously charged that EDT recommends an irrational policy of managing the news and “commends the ostrich as rational”. Lewis was right, but the case he appealed to—Newcomb’s Problem—does not demonstrate his conclusion. Indeed, decision theories other than EDT, such as Committal Decision Theory and Functional Decision Theory, agree with EDT's verdicts in Newcomb’s Problem, but their flaws, whatever they may be, do not stem from any (...) ostrich-like recommendations. We offer a new case which shows that EDT mismanages the news, thus vindicating Lewis’s original charge. We argue that this case reveals a flaw in the “Why ain’cha rich?” defense of EDT. We argue further that this case is an advance on extant putative counterexamples to EDT. (shrink)

The Mathematical Principles of Natural Philosophy.

This paper discusses the logical space of alternative conceptual engineering projects, with a specific focus on (1) the processes, (2) the targets and goals, and (3) the methods of such projects. We present an overview of how these three aspects interact in the contemporary literature and discuss those alternative projects that have yet to be explored based on our suggested typology. We show how choices about each element in a conceptual engineering project constrain the possibilities for the others, thereby giving (...) rise to distinct groupings of possible projects under the banner of conceptual engineering. We conclude with a critical reflection on the potential ethical issues that arise as a result of effectively putting conceptual engineering into practice. (shrink)

There has recently been increasing interest in the possibility and ethics of lethal autonomous weapons systems (LAWS), which would combine sophisticated AI with machinery capable of deadly force. One objection to LAWS is that their use will create a troubling responsibility gap, where no human agent can properly be held accountable for the outcomes that they create. While some authors have attempted to show that individual agents can, in fact, be responsible for the behaviour of LAWS in various circumstances, this (...) will not be possible in all cases. This article argues, however, that by assigning responsibilities to group agents operating within the military‐industrial complex, as well as the military‐industrial complex as a whole, we may be able to close the responsibility gap, or at least reduce its costs. Insofar as the potential for responsibility gaps poses an ethical barrier to the development and deployment of LAWS, this argument, if sound, may show their use to be morally permissible in a greater range of cases. (shrink)

We present a novel model of individual people, online posts, and media platforms to explain the online spread of epistemically toxic content such as fake news and suggest possible responses. We argue that a combination of technical features, such as the algorithmically curated feed structure, and social features, such as the absence of stable social-epistemic norms of posting and sharing in social media, is largely responsible for the unchecked spread of epistemically toxic content online. Sharing constitutes a distinctive communicative act, (...) governed by a dedicated norm and motivated to a large extent by social identity maintenance. But confusion about this norm and its lack of inherent epistemic checks lead readers to misunderstand posts, attribute excess or insufficient credibility to posts, and allow posters to evade epistemic accountability—all contributing to the spread of epistemically toxic content online. This spread can be effectively addressed if people and platforms add significantly more context to shared posts and platforms nudge people to develop and follow recognized epistemic norms of posting and sharing. (shrink)

We demonstrate that an unlexicalized PCFG can parse much more accurately than previously shown, by making use of simple, linguistically motivated state splits, which break down false independence assumptions latent in a vanilla treebank grammar. Indeed, its performance of 86.36% (LP/LR F1) is better than that of early lexicalized PCFG models, and surprisingly close to the current state-of-theart. This result has potential uses beyond establishing a strong lower bound on the maximum possible accuracy of unlexicalized models: an unlexicalized PCFG is (...) much more compact, easier to replicate, and easier to interpret than more complex lexical models, and the parsing algorithms are simpler, more widely understood, of lower asymptotic complexity, and easier to optimize. (shrink)

Reproduces the text of Newton's dissertation on the nature and properties of light.

This major work challenges some widely held positions in epistemology - those of Peirce and Popper on the one hand and those of Quine and Kuhn on the other.

Typicality is routinely invoked in everyday contexts: bobcats are typically short-tailed; people are typically less than seven feet tall. Typicality is invoked in scientific contexts as well: typical gases expand; typical quantum systems exhibit probabilistic behaviour. And typicality facts like these support many explanations, both quotidian and scientific. But what is it for something to be typical? And how do typicality facts explain? In this paper, I propose a general theory of typicality. I analyse the notion of a typical property. (...) I provide a formalism for typicality explanations, and I give an account of why typicality explanations are explanatory. Along the way, I show how typicality facts explain a variety of phenomena, from everyday phenomena to the statistical mechanical behaviour of gases. Finally, I argue that typicality is not the same thing as probability. (shrink)

I will argue for two main points. First, the regress imbedded in infinitism need not be subject to the Structural Objection; and second, the Structural Objection does not pose a real problem for any regress. I will not be arguing for the correctness of my proposal directly. That is, as will become apparent soon, my proposal rests on two principles of reasoning which together entail infinitism and I will not present my arguments for those principles here. The purpose of this (...) paper is to show that the objections raised by Gillett do not pose a grave problem for infinitism. (shrink)

Why would God institute the practice of efficacious petitionary prayer? Why would God not simply give us what we need before we ask? I examine recently proposed solutions to this puzzle and argue that they are inadequate to explain why an omniscient and perfectly good God would act differently in response to prayer. I propose that God has reasons to not always maximize a creature’s good, even in a sinless world, and that petitionary prayer functions as a means to reward (...) those who trust God, to enable us to actively love those we cannot otherwise help, and to give the petitioner personal evidence of God’s existence and care for her, creating a virtuous cycle of increasing faith. I refine this proposal by responding to several objections involving human responsibility and the epistemology of divine action. Along the way, I offer several ways petitioners can recognize God’s having answered a prayer and how God might help us with some common obstacles to prayer. (shrink)

David Chalmers thinks his iPhone exemplifies the extended mind thesis by meeting the criteria ‎that he and Andy Clark established in their well-known 1998 paper. Andy Clark agrees. We take ‎this proposal seriously, evaluating the case of the GPS-enabled smartphone as a potential mind ‎extender. We argue that the “trust and glue” criteria enumerated by Clark and Chalmers are ‎incompatible with both the epistemic responsibilities that accompany everyday activities and the ‎practices of trust that enable users to discharge them. Prospects (...) for revision of the original ‎criteria are dim. We therefore call for a rejection of the trust criterion and a reevaluation of the ‎extended mind thesis.‎. (shrink)

My aim in this paper is to give a philosophical analysis of the relationship between contingently available technology and the knowledge that it makes possible. My concern is with what specific subjects can know in practice, given their particular conditions, especially available technology, rather than what can be known “in principle” by a hypothetical entity like Laplace’s Demon. The argument has two parts. In the first, I’ll construct a novel account of epistemic possibility that incorporates two pragmatic conditions: responsibility and (...) practicability. For example, whether subjects can gain knowledge depends in some circumstances on whether they have the capability of gathering relevant evidence. In turn, the possibility of undertaking such investigative activities depends in part on factors like ethical constraints, economical realities, and available technology. In the second part of the paper, I’ll introduce “technological possibility” to analyze the set of actions made possible by available technology. To help motivate the problem and later test my proposal, I’ll focus on a specific historical case, one of the earliest uses of digital electronic computers in a scientific investigation. I conclude that the epistemic possibility of gaining access to scientific knowledge about certain subjects depends (in some cases) on the technological possibility for making responsible investigations. (shrink)

This first critical edition of Isaac Abravanel’s correspondence opens a window into the cultural, political and commercial world of one of the first Jewish humanists of the quattrocento. Jewish leader of the expelled Sephardim after 1492, commentator of the Bible, Abravanel is a legendary figure of the Sephardic history. The edition of the letters along with the introductive essay that reconstructs their cultural background intends to connect the legendary figure of Abravanel to the major reason of his remarkable career: (...) his successful assimilation of Renaissance humanism. (shrink)

This comprehensive discussion of the problem of rational belief develops the subject on the pattern of Bayesian decision theory. The analogy with decision theory introduces philosophical issues not usually encountered in logical studies and suggests some promising new approaches to old problems."We owe Professor Levi a debt of gratitude for producing a book of such excellence. His own approach to inductive inference is not only original and profound, it also clarifies and transforms the work of his predecessors. In short, the (...) book deserves to become a classic....There is a great deal of interest in the book besides these basic matters [forumlating rules of acceptance]. Some of the most interesting chapters are those that examine the implications of such rules. The discussions of probability, generalization, and various forms of inference are brilliant and enlightening. Indeed, the problems and methods elaborated by Professor Levi in his book serve as a new foundation for the study of inductive inference."--Keith Lehrer, Nous"Levi's book is an extremely interesting report on 'tentative and speculative first steps' toward a decision-theoretic approach to inductive inference....Professor Levi is to be congratulated on his ingenious development and application of this approach...."--Richard C. Jeffrey, The Journal of Philosophy. (shrink)

Criminal justice systems have traditionally relied heavily on human decision-making, but new technologies are increasingly supplementing the human role in this sector. This paper considers what general limits need to be placed on the use of algorithms in sentencing decisions. It argues that, even once we can build algorithms that equal human decision-making capacities, strict constraints need to be placed on how they are designed and developed. The act of condemnation is a valuable element of criminal sentencing, and using algorithms (...) in sentencing – even in an advisory role – threatens to undermine this value. The paper argues that a principle of “meaningful public control” should be met in all sentencing decisions if they are to retain their condemnatory status. This principle requires that agents who have standing to act on behalf of the wider political community retain moral responsibility for all sentencing decisions. While this principle does not rule out the use of algorithms, it does require limits on how they are constructed. (shrink)

This book casts new light on the traditional disagreement between those who hold that we cannot be morally responsible for our actions if they are causally determined, and those who deny this. Klein suggests that reflection on the relation between justice and deprivation offers a way out of this perplexity.

I show that standard grounding conditions contradict standard conditions for the identities of propositions.