Tim Bayne

Which systems/organisms are conscious? New tests for consciousness (‘C-tests’) are urgently needed. There is persisting uncertainty about when consciousness arises in human development, when it is lost due to neurological disorders and brain injury, and how it is distributed in nonhuman species. This need is amplified by recent and rapid developments in artificial intelligence (AI), neural organoids, and xenobot technology. Although a number of C-tests have been proposed in recent years, most are of limited use, and currently we have no C-tests for many of the populations for which they are most critical. Here, we identify challenges facing any attempt to develop C-tests, propose a multidimensional classification of such tests, and identify strategies that might be used to validate them.

In this paper we develop a participatory model of the Christian doctrine of the atonement, according to which the atonement involves participating in the death and resurrection of Christ. In part one we argue that current models of the atonement—exemplary, penal, substitutionary and merit models—are unsatisfactory. The central problem with these models is that they assume a purely deontic conception of sin and, as a result, they fail to address sin as a relational and ontological problem. In part two we argue that a participatory model of the atonement is both exegetically and philosophically plausible, and should be taken seriously within philosophical theology.i..

Neural organoids are laboratory-generated entities that replicate certain structural and functional features of the human brain. Most neural organoids are disembodied—completely decoupled from sensory input and motor output. As such, questions about their potential capacity for consciousness are exceptionally difficult to answer. While not disputing the need for caution regarding certain neural organoid types, this paper appeals to two broad constraints on any adequate theory of consciousness—the first involving the dependence of consciousness on embodiment; the second involving the dependence of consciousness on representations—to argue that disembodied neural organoids are not plausible candidates for consciousness.

This collection of essays focuses on the interface between delusions and self-deception. As pathologies of belief, delusions and self-deception raise many of the same challenges for those seeking to understand them. Are delusions and self-deception entirely distinct phenomena, or might some forms of self-deception also qualify as delusional? To what extent might models of self-deception and delusion share common factors? In what ways do affect and motivation enter into normal belief-formation, and how might they be implicated in self-deception and delusion? The essays in this volume tackle these questions from both empirical and conceptual perspectives. Some contributors focus on the general question of how to locate self-deception and delusion within our taxonomy of psychological states. Some contributors ask whether particular delusions - such as the Capgras delusion or anosognosia for hemiplegia - might be explained by appeal to motivational and affective factors. And some contributors provide general models of motivated reasoning, against which theories of pathological belief-formation might be measured.

Beat perception has received very little attention from either philosophers of mind or philosophers of music. This neglect is unfortunate, for the topic is rich with philosophical interest. This article addresses two questions. The first concerns the nature of our experience of musical beat. Here, we argue that experiences of beat are forms of auditory perception. The second question concerns the nature of musical beat itself: what are beats? We defend a form of anthropocentric realism about beats: beats are mind‐independent properties of sound sequences whose nature can be understood only in relation to our perceptual capacities.

In the early modern period one can find unity of consciousness arguments in the writings of Rene Descartes and G. W. Leibniz, and in the recent literature they have been defended by David Barnett, William Hasker, and Richard Swinburne (among others). Descartes's unity of consciousness argument for dualism is to be found in the sixth of his Meditations on First Philosophy. Descartes claims that his unity of consciousness argument was itself sufficient to establish substance dualism. Swinburne's central line of argument involves deploying a number of puzzle cases. He argues that our intuitions about these cases can be accommodated only by adopting a “further fact” view of the self, according to which the continued existence of a person over time consists in the continued existence of a mental substance, and “it is metaphysically possible that the substance acquires a totally new body, totally new apparent memories, and character”.

In "The Disunity of Consciousness," Gerard O'Brien and Jon Opie argue that human consciousness is not synchronically unified. They suggest that the orthodox conception of the unity of consciousness admits of two readings, neither of which they find persuasive. According to them, "a conscious individual does not have a single consciousness, but several distinct phenomenal consciousnesses, at least one for each of the senses, running in parallel." They call this conception of consciousness the _multi-track account. I make three points in reply: (1) O'Brien and Opie's characterization of the orthodox conception of the unity of consciousness is problematic; (2) their arguments in support of the multitrack account are unpersuasive; and (3) the phenomenon of intersensory integration suggests that O'Brien and Opie are wrong to claim that "the only sense in which it is correct to talk of a 'unified' consciousness (...) is that in which the representational contents of the various components coincide."

Viewed from a certain perspective, nothing can seem more secure than introspection. Consider an ordinary conscious episode—say, your current visual experience of the colour of this page. You can judge, when reflecting on this experience, that you have a visual experience as of something white with black marks before you. Does it seem reasonable to doubt this introspective judgement? Surely not—such doubt would seem utterly fanciful. The trustworthiness of introspection is not only assumed by commonsense, it is also taken for granted by many of theorists about the mind. Within both philosophy and the science of consciousness it is widely held that introspection is generally reliable, at least with respect to the question of one’s current (or immediately prior) conscious states. Without this assumption, we could not make sense of theorists’ widespread use of introspection, both in support of their own position and to undermine that of their opponents

In 1997, a Scottish surgeon by the name of Robert Smith was approached by a man with an unusual request: he wanted his apparently healthy lower left leg amputated. Although details about the case are sketchy, the would-be amputee appears to have desired the amputation on the grounds that his left foot wasn’t part of him – it felt alien. After consultation with psychiatrists, Smith performed the amputation. Two and a half years later, the patient reported that his life had been transformed for the better by the operation [1]. A second patient was also reported as having been satisfied with his amputation [2]

Developments in the philosophy of mind over the last 20 years have dramatically changed the nature of the subject. In this major new introduction, Tim Bayne presents an outstanding overview of many of the key topics, problems, and debates, taking account not only of changes in philosophy of mind itself but also of important developments in the scientific study of the mind. The following topics are discussed in depth: What distinguishes a physicalist conception of the mind? Behaviourism, the identity theory, functionalism, and eliminativism as accounts of the mental The nature of perception, including the issue of perceptual transparency, the admissible contents of perception, and the question of unconscious perception The nature of thought, including the language of thought hypothesis, Searle’s Chinese room argument, and the Turing test The basis of intentional content Externalist accounts of content and the ‘extended mind’ thesis Consciousness-based objections to physicalism, and illusionist and panpsychist conceptions of consciousness Theories of consciousness, including methodological issues in the study of consciousness Mental causation, including both philosophical and scientific challenges The problem(s) of other minds, including knowledge of non-human minds Self-knowledge Personal identity and the nature of the self The book features a number of boxes that provide a more in-depth look at particular issues. Also included are chapter summaries, guides to further reading, and a helpful glossary of terms. Written by a leading figure in the field, Philosophy of Mind: An Introduction is an invaluable core text for any student coming to philosophy of mind for the first time.

We have various everyday measures for identifying the presence of consciousness, such as the capacity for verbal report and the intentional control of behavior. However, there are many contexts in which these measures are difficult to apply, and even when they can be applied one might have doubts as to their validity in determining the presence/absence of consciousness. Everyday measures for identifying consciousness are particularly problematic when it comes to ‘challenging cases’—human infants, people with brain damage, nonhuman animals, and AI systems. There is a pressing need to identify measures of consciousness that can be applied to challenging cases. This paper explores one of the most promising strategies for identifying and validating such measures—the natural-kind strategy. The paper is in two broad parts. Part I introduces the natural-kind strategy, and contrasts it with other influential approaches in the field. Part II considers a number of objections to the approach, arguing that none succeeds.

At present, the science of consciousness is structured around the search for the neural correlates of consciousness. One of the alleged advantages of the NCCs framework is its metaphysical neutrality—the fact that it begs no contested questions with respect to debates about the fundamental nature of consciousness. Here, we argue that even if the NCC framework is metaphysically neutral, it is structurally committed, for it presupposes a certain model—what we call the Lite-Brite model—of consciousness. This, we argue, represents a serious liability for the NCC framework for the plausibility of the Lite-Brite model is very much an open question, and the science of consciousness would be better served by a framework that does not presuppose it. Drawing on interventionist ideas in the philosophy of science, we suggest that the Difference-Maker framework can provide just such an alternative. Instead of searching for the neural correlates of consciousness, we ought to be searching for the difference makers of consciousness. We detail how a shift to searching DMCs will change both the practice of consciousness science and the interpretation of existing results.

The on-going debate over the ‘admissible contents of perceptual experience’ concerns the range of properties that human beings are directly acquainted with in perceptual experience. Regarding vision, it is relatively uncontroversial that the following properties can figure in the contents of visual experience: colour, shape, illumination, spatial relations, motion, and texture. The controversy begins when we ask whether any properties besides these figure in visual experience. We argue that ‘ensemble properties’ should be added to the list of visually admissible properties. Ensemble properties are features that belong to a set of perceptible objects as a whole as opposed to the individuals that constitute that set. They include such features as the mean size of an array of shapes or the average emotional expression of an array of faces. Recent work in vision science has yielded compelling evidence that the visual system routinely encodes such properties. We argue that epistemological considerations provide strong reasons to think that these properties figure in visual experience. Judgements about ensemble properties are immediately warranted by our perceptual experience, and the only plausible way that a perceptual experience could confer this warrant is if it confers awareness of ensemble properties.

A central debate in the philosophy of perception concerns the range of properties that can be represented in perceptual experience. Are the contents of perceptual experience restricted to ‘low-level’ properties such as location, shape and texture, or can ‘high-level’ properties such as being a tomato, being a pine tree or being a watch also be represented in perceptual experience? This paper explores the bearing of gist perception on the admissible contents debate, arguing that it provides qualified support for the claim that certain kinds of high-level properties—such as being a natural scene —can be perceptually represented.

Unlike surrogacy and cloning, reproduction via gamete donation is widely assumed to be morally unproblematic. Recently, a number of authors have argued that this assumption is mistaken: gamete donors, they claim, have parental responsibilities that they typically treat too lightly. In this paper I argue that the ‘parental neglect’ case against gamete donation fails. I begin by examining and rejecting the view that gamete donors have parental responsibilities; I claim that none of the current accounts of parenthood provides good reason for ascribing parenthood to gamete donors. I then argue that even if gamete donors do have parental responsibilities for ‘their’ children, it is not clear that they treat these responsibilities too lightly. I conclude the paper by examining the wider question of just what kind of responsibilities gamete donors might have towards the children that they have a role in creating.

One of the many fault-lines within accounts of consciousness concerns the unity of consciousness. Some theorists claim that consciousness is unified—indeed, some theorists insist that consciousness is essentially unified. Other theorists assert that the unity of consciousness is an illusion, and that consciousness is often, if not invariably, disunified. Unfortunately, it is rare for proponents of either side of the debate to explain what the unity of consciousness might involve. What would it mean for consciousness to be unified? In this chapter I provide a brief cartography of the unity of consciousness. In the next section I introduce a number of unity relations that can hold between conscious states, and in the following sections I show how these unity relations can be used to construct various conceptions of the unity of consciousness—what I call unity theses. These unity theses provide us with a set of reference points by means of which we can orient discussions of the unity of consciousness.

From the first-person point of view, seeing a red square is very different from thinking about a red square, hearing an alarm sound is very different from thinking that an alarm is sounding, and smelling freshly-roasted coffee is very different from thinking that there is freshly-roasted coffee in one’s vicinity. How might the familiar contrast between representing a fact in thought and representing it in perception be captured? One influential idea is that perceptual states are phenomenally conscious whereas thoughts are not. However, those theorists who hold that thoughts have a distinctive kind of phenomenal character – often known as “cognitive phenomenology” – cannot account for the contrast between thought and perception in this manner. This paper examines the various options that are available to advocates of cognitive phenomenology for capturing the experiential contrast between thought and perception, and argues that each of them faces serious challenges.

At any given time, a subject has a multiplicity of conscious experiences. A subject might simultaneously have visual experiences of a red book and a green tree, auditory experiences of birds singing, bodily sensations of a faint hunger and a sharp pain in the shoulder, the emotional experience of a certain melancholy, while having a stream of conscious thoughts about the nature of reality. These experiences are distinct from each other: a subject could experience the red book without the singing birds, and could experience the singing birds without the red book. But at the same time, the experiences seem to be tied together in a deep way. They seem to be unified, by being aspects of a single encompassing state of consciousness