The classic, influential essay in 'descriptive metaphysics' by the distinguished English philosopher.

In Europe, telecare is the use of remote monitoring technology to enable vulnerable people to live independently in their own homes. The technology includes electronic tags and sensors that transmit information about the user's location and patterns of behavior in the user's home to an external hub, where it can trigger an intervention in an emergency. Telecare users in the United Kingdom sometimes report their unease about being monitored by a ?Big Brother,? and the same kind of electronic tags that (...) alert telecare hubs to the movements of someone with dementia who is ?wandering? are worn by terrorist suspects who have been placed under house arrest. For these and other reasons, such as ordinary privacy concerns, telecare is sometimes regarded as an objectionable extension of a ?surveillance state.? In this article, we defend the use of telecare against the charge that it is Orwellian. In the United States, the conception of telecare primarily as telemedicine, and the fact that it is not typically a government responsibility, make a supposed connection with a surveillance state even more doubtful than in Europe. The main objection, we argue, to telecare is not its intrusiveness, but the danger of its deepening the isolation of those who use it. There are ways of organizing telecare so that the independence and privacy of users are enhanced, but personal isolation may be harder to address. As telecare is a means of reducing the cost of publicly provided social and health care, and the need to reduce public spending is growing, the correlative problem of isolation must be addressed alongside the goal of promoting independence. (shrink)

This article looks at the way people determine the antecedent of a pronoun in sentence pairs, such as: Albert invited Ron to dinner. He spent hours cleaning the house. The experiment reported here is motivated by the idea that such judgments depend on reasoning about identity . Because the identity of an individual over time depends on the causal-historical path connecting the stages of the individual, the correct antecedent will also depend on causal connections. The experiment varied how likely it (...) is that the event of the first sentence would cause the event of the second for each of the two individuals . Decisions about the antecedent followed causal likelihood. A mathematical model of causal identity accounted for most of the key aspects of the data from the individual sentence pairs. (shrink)

How do humans manage to keep track of a gradually changing object or person as the same persisting individual despite the fact that the extraction of information about this individual must often rely on heterogeneous information sources and heterogeneous tracking methods? The article introduces the Empirical Tracking of Individuals theory to address this problem. This theory proposes an analysis of the concept of integrated tracking, which refers to the capacity to acquire, store, and update information about the identity and location (...) of individuals in our environment. It hypothesizes that certain functions of attention are a key to explaining how the cognitive flexibility of the human mind overcomes the heterogeneity of sources and methods in integrated tracking. At least two premises lend support to this hypothesis. First, heterogeneity of tracking sources is overcome by the combination of information from multiple perceptual modalities and a phenomenon of multisensory 'transparency'. Second, heterogeneity of tracking sources and methods may also be overcome by inferences that combine information across domains to acquire reasons to believe propositions about the target's location and identity. (shrink)

This paper examines people's reasoning about identity continuity and its relation to previous research on how people value one-of-a-kind artifacts, such as artwork. We propose that judgments about the continuity of artworks are related to judgments about the continuity of individual persons because art objects are seen as physical extensions of their creators. We report a reanalysis of previous data and the results of two new empirical studies that test this hypothesis. The first study demonstrates that the mere categorization of (...) an object as “art” versus “a tool” changes people's intuitions about the persistence of those objects over time. In a second study, we examine some conditions that may lead artworks to be thought of as different from other artifacts. These observations inform both current understanding of what makes some objects one-of-a-kind as well as broader questions regarding how people intuitively think about the persistence of human agents. (shrink)

In philosophy, “singular thought” refers to our capacity to represent entities as individuals, rather than as possessors of properties. Philosophers who defend singularism argue that perception allows us to mentally latch onto objects and persons directly, without conceptualizing them as being of a certain sort. Singularists assume that singular thought forms a unified psychological kind, regardless of the nature of the individuals represented. Empirical findings on the special psychological role of persons as opposed to inanimates threaten singularism. They raise the (...) possibility that tracking individuals specifically as persons might require conceptualizing them in certain ways, for example, as persons. In this paper, we take such a possibility seriously but ultimately reject it. Instead, we propose to revise a prominent singularist theory, the theory of mental files, in order to accommodate data on the psychological distinctiveness of persons: We advocate the postulation of perceptual person-files. Perceptual tracking via person-files is different from object-tracking but also from descriptive classification under the sortal concept PERSON. (shrink)

A comprehensive study of the ethics of killing in cases in which the metaphysical or moral status of the individual killed is uncertain or controversial. Among those beings whose status is questionable or marginal in this way are human embryos and fetuses, newborn infants, animals, anencephalic infants, human beings with severe congenital and cognitive impairments, and human beings who have become severely demented or irreversibly comatose. In an effort to understand the moral status of these beings, this book develops and (...) defends distinctive accounts of the nature of personal identity, the evaluation of death, and the wrongness of killing. The central metaphysical claim of the book is that we are neither nonmaterial souls nor human organisms but are instead embodied minds. In ethical theory, one of the central claims is that the morality of killing is not unitary; rather, the principles that determine the morality of killing in marginal cases are different from those that govern the killing of persons who are self‐conscious and rational. Another important theme is that killing in marginal cases should be evaluated in terms of the impact it would have on the victim at the time rather than on the value of the victim's life as a whole. What primarily matters is how killing would affect that which would be rational for the victim to care about at the time of death. By appealing to various foundational claims about identity, death, and the morality of killing, this book yields novel conclusions about such issues as abortion, prenatal injury, infanticide, the killing of animals, the significance of brain death, the termination of life support in cases of persistent vegetative state, the use of anencephalic infants as sources of organs for transplantation, euthanasia, assisted suicide, and advance directives in cases of dementia. In particular, the book defends the moral permissibility of abortion, infanticide, and euthanasia in certain cases and argues that brain death is not the appropriate criterion of death either for a person or a human organism. (shrink)

Fregoli delusion is the mistaken belief that some person currently present in the deluded person's environment is a familiar person in disguise. The stranger is believed to be psychologically identical to this known person even though the deluded person perceives the physical appearance of the stranger as being different from the known person's typical appearance. To gain a deeper understanding of this contradictory error in the normal system for tracking and identifying known persons, we conducted a detailed survey of all (...) the Fregoli cases reported in the literature since the seminal Courbon and Fail paper. Our preliminary reading of these cases revealed a notable lack of definitional clarity. So, we first formulated a classification scheme of different person misidentification delusions so as to identify those cases that qualified as instances of Fregoli according to the above characterization: the mistaken belief that a known person is present in the environment in a different guise to his or her typical appearance. We identified 38 clear cases of this type and set out to answer a series of questions motivated by current hypotheses about the origin of the Fregoli delusion. We asked whether the patients misidentified particular strangers, made reference to the misidentified known persons using wigs or plastic surgery , misidentified many different strangers or only one, showed other symptoms , and made inferences about the motives of the known persons in disguise. We conclude by discussing the implications of our findings for current hypotheses concerning the origin of the Fregoli delusion. (shrink)

We propose that there is a powerful human disposition to track the actions and possessions of agents. In two experiments, 3-year-olds and adults viewed sets of objects, learned a new fact about one of the objects in each set , and were queried about either the taught fact or an unrelated dimension immediately after a spatiotemporal transformation, and after a delay. Adults uniformly tracked object identity under all conditions, whereas children tracked identity more when taught ownership versus labeling information, and (...) only regarding the taught fact . These findings suggest that the special attention that children and adults pay to agents readily extends to include inanimate objects. That young children track an object's history, despite their reliance on surface features on many cognitive tasks, suggests that unobservable historical features are foundational in human cognition. (shrink)

Through the use of such "folk" concepts as belief, desire, intention, and expectation, Daniel Dennett asserts in this first full scale presentation of...

This article discusses how research on the image-based analysis of facial images has informed this debate by demonstrating that a single representational system for facial identity and facial expression is not only computationally viable, but can simulate existing cognitive data demonstrating apparent dissociable processing of these two facial properties. It discusses the increasing number of cognitive studies that provide support for this view. Neuropsychological case studies of brain-injured patients and provide limited evidence for separate visual routes processing facial identity and (...) facial expression. It deals with neuroimaging studies addressing both facial identity and facial expression processing which shows that the fusiform gyrus contributes to the recognition of both facial properties. Research continues to reinforce the proposal that a common visual framework supports the representation of at least some aspects of facial identity and facial expression. (shrink)

The lack of consensus on how to characterize humans’ capacity for belief reasoning has been brought into sharp focus by recent research. Children fail critical tests of belief reasoning before 3 to 4 years (Wellman, Cross, & Watson, 2001; Wimmer & Perner, 1983), yet infants apparently pass false belief tasks at 13 or 15 months (Onishi & Baillargeon, 2005; Surian, Caldi, & Sperber, 2007). Non-human animals also fail critical tests of belief reasoning but can show very complex social behaviour (e.g., (...) Call & Tomasello, 2005). Fluent social interaction in adult humans implies efficient processing of beliefs, yet direct tests suggest that belief reasoning is cognitively demanding, even for adults (e.g., Apperly, Samson & Humphreys, 2005). We interpret these findings by drawing an analogy with the domain of number cognition, where similarly contrasting results have been observed. We propose that the success of infants and non-human animals on some belief reasoning tasks may be best explained by a cognitively efficient but inflexible capacity for tracking belief-like states. In humans this capacity persists in parallel with later-developing, more flexible but more cognitively demanding theory of mind abilities. (shrink)

To introduce the issue of the tracking and identification of human agents, I examine the ability of an agent to track a human person and distinguish this target from other individuals: The ability to perform person identification. First, I discuss influential mechanistic models of the perceptual recognition of human faces and people. Such models propose detailed hypotheses about the parts and activities of the mental mechanisms that control the perceptual recognition of persons. However, models based on perceptual recognition are incomplete (...) theories of person identification because they do not explain several identification behaviors that are fundamental to human social interactions. Furthermore, recognition-based models tend to appeal to the controversial concept of the “identity” of a person without explaining what determines personal identity and persistence. To overcome these limitations, I propose to integrate the face-recognition program into a broader causal-historical theory of identification. The causal-historical theory of identification complements models focused on perceptual recognition because it can account for the types of non-perceptual identification overlooked by the face-recognition program. Moreover, it can decompose the identification behaviors into tracking processes that succeed or fail to be sensitive to causal characteristics of a target. I illustrate these advantages with a discussion of the difference between the tracking of a person understood as either a causally continuous biological organism or a psychologically continuous mind. Finally, I argue that the causal-historical theory provides a theoretical framework for investigating the tracking of relations between a target and its contextual and historical attributes, such as a target's possessions. (shrink)

To explain agent-identification behaviours, universalist theories in the biological and cognitive sciences have posited mental mechanisms thought to be universal to all humans, such as agent detection and face recognition mechanisms. These universalist theories have paid little attention to how particular sociocultural or historical contexts interact with the psychobiological processes of agent-identification. In contrast to universalist theories, contextualist theories appeal to particular historical and sociocultural contexts for explaining agent-identification. Contextualist theories tend to adopt idiographic methods aimed at recording the heterogeneity (...) of human behaviours across history, space, and cultures. Defenders of the universalist approach tend to criticise idiographic methods because such methods can lead to relativism or may lack generality. To overcome explanatory limitations of proposals that adopt either universalist or contextualist approaches in isolation, I propose a philosophical model that integrates contributions from both traditions: the psycho-historical theory of agent-identification. This theory investigates how the tracking processes that humans use for identifying agents interact with the unique socio-historical contexts that support agent-identification practices. In integrating hypotheses about the history of agents with psychological and epistemological principles regarding agent-identification, the theory can generate novel hypotheses regarding the distinction between recognition-based, heuristic-based, and explanation-based agent-identification. (shrink)

(in press, under contract with MIT Press, accepted on June 30th, 2006). Attention, Information and Epistemic Perception. In Terzis, G. & Arp, R. (Eds) Information and the Living Systems: Essays in the Philosophy of Biology. The MIT Press. (14,000 words).

Tracking persons, that is, determining that a person now is or is not a specific earlier person, is extremely common and widespread in our way of life and extremely important. If so, figuring out what we are tracking, what it is to persist as a person over a period of time, is also important. Trying to figure this out will be the main focus of this chapter.

This revised edition includes a new Preface outlining developments in Relevance Theory since 1986, discussing the more serious criticisms of the theory, and ...