The book is an extended study of the problem of consciousness. After setting up the problem, I argue that reductive explanation of consciousness is impossible , and that if one takes consciousness seriously, one has to go beyond a strict materialist framework. In the second half of the book, I move toward a positive theory of consciousness with fundamental laws linking the physical and the experiential in a systematic way. Finally, I use the ideas and arguments (...) developed earlier to defend a form of strong artificial intelligence and to analyze some problems in the foundations of quantum mechanics. (shrink)

How can phenomenal consciousness exist as an integral part of a physical universe? How can the technicolour phenomenology of our inner lives be created out of the complex neural activities of our brains? Many have despaired of finding answers to these questions; and many have claimed that human consciousness is inherently mysterious. Peter Carruthers argues, on the contrary, that the subjective feel of our experience is fully explicable in naturalistic terms. Drawing on a variety of interdisciplinary resources, he (...) develops and defends a novel account in terms of higher-order thought. He shows that this can explain away some of the more extravagant claims made about phenomenal consciousness, while substantively explaining the key subjectivity of our experience. Written with characteristic clarity and directness, and surveying a wide range of extant theories, this book is essential reading for all those within philosophy and psychology interested in the problem of consciousness. (shrink)

The Conscious Brain brings neuroscientific evidence to bear on enduring philosophical questions. Major philosophical and scientific theories of consciousness are surveyed, challenged, and extended.

Consciousness fits uneasily into our conception of the natural world. On the most common conception of nature, the natural world is the physical world. But on the most common conception of consciousness, it is not easy to see how it could be part of the physical world. So it seems that to find a place for consciousness within the natural order, we must either revise our conception of consciousness, or revise our conception of nature. In twentieth-century (...) philosophy, this dilemma is posed most acutely in C. D. Broad’s The Mind and its Place in Nature . The phenomena of mind, for Broad, are the phenomena of consciousness. The central problem is that of locating mind with respect to the physical world. Broad’s exhaustive discussion of the problem culminates in a taxonomy of seventeen different views of the mental-physical relation.1 On Broad’s taxonomy, a view might see the mental as nonexistent , as reducible, as emergent, or as a basic property of a substance . The physical might be seen in one of the same four ways. So a four-by-four matrix of views results. At the end, three views are left standing: those on which mentality is an emergent characteristic of either a physical substance or a neutral substance, where in the latter case, the physical might be either emergent or delusive. (shrink)

Does consciousness collapse the quantum wave function? This idea was taken seriously by John von Neumann and Eugene Wigner but is now widely dismissed. We develop the idea by combining a mathematical theory of consciousness (integrated information theory) with an account of quantum collapse dynamics (continuous spontaneous localization). Simple versions of the theory are falsified by the quantum Zeno effect, but more complex versions remain compatible with empirical evidence. In principle, versions of the theory can be tested by (...) experiments with quantum computers. The upshot is not that consciousness-collapse interpretations are clearly correct, but that there is a research program here worth exploring. (shrink)

Amidst the many brain events evoked by a visual stimulus, which are specifically associated with conscious perception, and which merely reflect non-conscious processing? Several recent neuroimaging studies have contrasted conscious and non-conscious visual processing, but their results appear inconsistent. Some support a correlation of conscious perception with early occipital events, others with late parieto-frontal activity. Here we attempt to make sense of those dissenting results. On the basis of a minimal neuro-computational model, the global neuronal workspace hypothesis, we propose a (...) taxonomy which distinguishes between vigilance and access to conscious report, as well as between subliminal, preconscious and conscious processing. We suggest that these distinctions map onto different neural mechanisms, and that conscious perception is systematically associated with a sudden surge of parieto-frontal activity causing top-down amplification. (shrink)

Consciousness is, perhaps, the aspect of our mental lives that is the most perplexing for both psychologists and philosophers. Daniel Dennett has described it as 'both the most obvious and the most mysterious feature of our minds' and attempts at definition often seem to move in circles. Thomas Nagel famously remarked that 'without consciousness the mind-body problem would be much less interesting. With consciousness it seems hopeless.'. These observations might suggest that consciousness - indefinable and mysterious (...) - falls outside the scope of rational enquiry, defying both scientific and philosophical investigation. In reality, however, the topic has been a focus of psychological investigation since William James and is increasingly vital in philosophical research. This book illustrates the various, interdisciplinary approaches to the problem, providing both pointers to a solution and a summary of the key positions. (shrink)

We have a much better understanding of physics than we do of consciousness. I consider ways in which intrinsically mental aspects of fundamental ontology might induce modifications of the known laws of physics, or whether they could be relevant to accounting for consciousness if no such modifications exist. I suggest that our current knowledge of physics should make us skeptical of hypothetical modifications of the known rules, and that without such modifications it’s hard to imagine how intrinsically mental (...) aspects could play a useful explanatory role. Draft version of a paper submitted to Journal of Consciousness Studies, special issue responding to Philip Goff’s Galileo’s Error: Foundations for a New Science of Consciousness. (shrink)

A breathtaking look at the new science that can track consciousness deep in the brain How does our brain generate a conscious thought? And why does so much of our knowledge remain unconscious? Thanks to clever psychological and brain-imaging experiments, scientists are closer to cracking this mystery than ever before. In this lively book, Stanislas Dehaene describes the pioneering work his lab and the labs of other cognitive neuroscientists worldwide have accomplished in defining, testing, and explaining the brain events (...) behind a conscious state. We can now pin down the neurons that fire when a person reports becoming aware of a piece of information and understand the crucial role unconscious computations play in how we make decisions. The emerging theory enables a test of consciousness in animals, babies, and those with severe brain injuries. A joyous exploration of the mind and its thrilling complexities, Consciousness and the Brain will excite anyone interested in cutting-edge science and technology and the vast philosophical, personal, and ethical implications of finally quantifying consciousness. (shrink)

Philosophers traditionally recognize two main features of mental states: intentionality and phenomenal consciousness. To a first approximation, intentionality is the aboutness of mental states, and phenomenal consciousness is the felt, experiential, qualitative, or "what it's like" aspect of mental states. In the past few decades, these features have been widely assumed to be distinct and independent. But several philosophers have recently challenged this assumption, arguing that intentionality and consciousness are importantly related. This article overviews the key views (...) on the relationship between consciousness and intentionality and describes our favored view, which is a version of the phenomenal intentionality theory, roughly the view that the most fundamental kind of intentionality arises from phenomenal consciousness. (shrink)

Perceptual attention is essential to both thought and agency, for there is arguably no demonstrative thought or bodily action without it. Psychologists and philosophers since William James have taken attention to be a ubiquitous and distinctive form of consciousness, one that leaves a characteristic mark on perceptual experience. As a process of selecting specific perceptual inputs, attention influences the way things perceptually appear. It may then seem that it is a specific feature of perceptual representation that constitutes what it (...) is like to consciously attend to an object. In fact conscious attention is more complicated. In what follows, I argue that the phenomenology of conscious attention to what is perceived involves not just a way of perceptually locking on to a specific object. It necessarily involves a way of cognitively locking on to it as well. (shrink)

Conscious perception, like the sight of a coffee cup, seems to involve the brain identifying a stimulus. But conscious input activates more brain regions than are needed to identify coffee cups and faces. It spreads beyond sensory cortex to frontoparietal association areas, which do not serve stimulus identification as such. What is the role of those regions? Parietal cortex support the ‘first person perspective’ on the visual world, unconsciously framing the visual object stream. Some prefrontal areas select and interpret conscious (...) events for executive control. Such functions can be viewed as properties of the subject, rather than the object, of experience – the ‘observing self’ that appears to be needed to maintain the conscious state. (shrink)

Consciousness and Mind presents David Rosenthal's influential work on the nature of consciousness. Central to that work is Rosenthal's higher-order-thought theory of consciousness, according to which a sensation, thought, or other mental state is conscious if one has a higher-order thought that one is in that state. The first four essays develop various aspects of that theory. The next three essays present Rosenthal's homomorphism theory of mental qualities and qualitative consciousness, and show how that theory fits (...) with and helps sustain the HOT theory. A crucial feature of homomorphism theory is that it individuates and taxonomizes mental qualities independently of the way we're conscious of them, and indeed independently of our being conscious of them at all. So the theory accommodates the qualitative character not only of conscious sensations and perceptions, but also of those which fall outside our stream of consciousness. Rosenthal argues that, because this account of mental qualities makes no appeal to consciousness, it enables us to dispel such traditional quandaries as the alleged conceivability of undetectable quality inversion, and to disarm various apparent obstacles to explaining qualitative consciousness and understanding its nature. Six further essays build on the HOT theory to explain various important features of consciousness, among them the complex connections that hold in humans between consciousness and speech, the self-interpretative aspect of consciousness, and the compelling sense we have that consciousness is unified. Two of the essays, one an extended treatment of homomorphism theory, appear here for the first time. There is also a substantive introduction, which draws out the connections between the essays and highlights their implications. (shrink)

Consciousness seems to be an enigmatic phenomenon: it is difficult to imagine how our perceptions of the world and our inner thoughts, sensations and feelings could be related to the immensely complicated biological organ we call the brain. This volume presents the thoughts of some of the leading philosophers and cognitive scientists who have recently participated in the discussion of the status of consciousness in science. The focus of inquiry is the question: "Is it possible to incorporate (...) class='Hi'>consciousness into science?" Philosophers have suggested different alternatives -- some think that consciousness should be altogether eliminated from science because it is not a real phenomenon, others that consciousness is a real, higher-level physical or neurobiological phenomenon, and still others that consciousness is fundamentally mysterious and beyond the reach of science. At the same time, however, several models or theories of the role of conscious processing in the brain have been developed in the more empirical cognitive sciences. It has been suggested that non-conscious processes must be sharply separated from conscious ones, and that the necessity of this distinction is manifested in the curious behavior of certain brain-damaged patients. This book demonstrates the dialogue between philosophical and empirical points of view. The writers present alternative solutions to the brain-consciousness problem and they discuss how the unification of biological and psychological sciences could thus become feasible. Covering a large ground, this book shows how the philosophical and empirical problems are closely interconnected. From this interdisciplinary exploration emerges the conviction that consciousness can and should be a natural part of our scientific world view. (shrink)

How can we disentangle the neural basis of phenomenal consciousness from the neural machinery of the cognitive access that underlies reports of phenomenal consciousness? We can see the problem in stark form if we ask how we could tell whether representations inside a Fodorian module are phenomenally conscious. The methodology would seem straightforward: find the neural natural kinds that are the basis of phenomenal consciousness in clear cases when subjects are completely confident and we have no reason (...) to doubt their authority, and look to see whether those neural natural kinds exist within Fodorian modules. But a puzzle arises: do we include the machinery underlying reportability within the neural natural kinds of the clear cases? If the answer is ‘Yes’, then there can be no phenomenally conscious representations in Fodorian modules. But how can we know if the answer is ‘Yes’? The suggested methodology requires an answer to the question it was supposed to answer! The paper argues for an abstract solution to the problem and exhibits a source of empirical data that is relevant, data that show that in a certain sense phenomenal consciousness overflows cognitive accessibility. The paper argues that we can find a neural realizer of this overflow if assume that the neural basis of phenomenal consciousness does not include the neural basis of cognitive accessibility and that this assumption is justified by the explanations it allows. (shrink)

What is consciousness? How does the subjective character of consciousness fit into an objective world? How can there be a science of consciousness? In this sequel to his groundbreaking and controversial The Conscious Mind, David Chalmers develops a unified framework that addresses these questions and many others. Starting with a statement of the "hard problem" of consciousness, Chalmers builds a positive framework for the science of consciousness and a nonreductive vision of the metaphysics of (...) class='Hi'>consciousness. He replies to many critics of The Conscious Mind, and then develops a positive theory in new directions. The book includes original accounts of how we think and know about consciousness, of the unity of consciousness, and of how consciousness relates to the external world. Along the way, Chalmers develops many provocative ideas: the " consciousness meter", the Garden of Eden as a model of perceptual experience, and The Matrix as a guide to the deepest philosophical problems about consciousness and the external world. This book will be required reading for anyone interested in the problems of mind, brain, consciousness, and reality. (shrink)

The first half of this book argues that physicalism cannot account for consciousness, and hence cannot be true. The second half explores and defends Russellian monism, a radical alternative to both physicalism and dualism. The view that emerges combines panpsychism with the view that the universe as a whole is fundamental.

Peter Carruthers's essays on consciousness and related issues have had a substantial impact on the field, and many of his best are now collected here in revised form. The first half of the volume is devoted to developing, elaborating, and defending against competitors one particular sort of reductive explanation of phenomenal consciousness, which Carruthers now refers to as 'dual-content theory'. Phenomenal consciousness - the feel of experience - is supposed to constitute the 'hard problem' for a scientific (...) world view, and many have claimed that it is an irredeemable mystery. But Carruthers here claims to have explained it. He argues that phenomenally conscious states are ones that possess both an 'analog' intentional content and a corresponding higher-order analog content, representing the first-order content of the experience. It is the higher-order analog content that enables our phenomenally conscious experiences to present themselves to us, and that constitutes their distinctive subjective aspect, or feel.The next two chapters explore some of the differences between conscious experience and conscious thought, and argue for the plausibility of some kind of eliminativism about conscious thinking. Then the final four chapters focus on the minds of non-human animals. Carruthers argues that even if the experiences of animals aren't phenomenally conscious, this needn't prevent the frustrations and sufferings of animals from being appropriate objects of sympathy and concern. Nor need it mean that there is any sort of radical 'Cartesian divide' between our minds and theirs of deep significance for comparative psychology. In the final chapter, he argues provocatively that even insects have minds that include a belief/desire/perception psychology much like our own. So mindedness and phenomenal consciousness couldn't be further apart.Carruthers's writing throughout is distinctively clear and direct. The collection will be of great interest to anyone working in philosophy of mind or cognitive science. (shrink)

Owen Flanagan argues that we are on the way to understanding consciousness and its place in the natural order.

Some mental events are conscious, some are unconscious. What is the difference between the two? Uriah Kriegel offers an answer. His aim is a comprehensive theory of the features that all and only conscious mental events have. The key idea is that consciousness arises when self-awareness and world-awareness are integrated in the right way. Conscious mental events differ from unconscious ones in that, whatever else they may represent, they always also represent themselves, and do so in a very specific (...) way. Subjective Consciousness is a fascinating new move forward towards a full understanding of the mind. (shrink)

In Consciousness and Persons: Unity and Identity, Michael Tye takes on the thorny issue of the unity of consciousness and answers these important questions: What exactly is the unity of consciousness? Can a single person have a divided consciousness? What is a single person? Tye argues that unity is a fundamental part of human consciousness -- something so basic to everyday experience that it is easy to overlook. For example, when we hear the sound of (...) waves crashing on a beach and at the same time see a red warning flag, there is an overall unity to our experience; the sound and the red shape are presented together in our consciousness. Similarly, when we undergo a succession of thoughts as we think something through, there is an experience of succession that unifies the thoughts into a conscious whole. But, Tye shows, consciousness is not always unified. Split-brain subjects, whose corpus callosum has been severed, are usually taken to have a divided or disunified consciousness. Their behavior in certain situations implies that they have lost the unity normal human subjects take for granted; it is sometimes even supposed that a split-brain subject is really two persons.Tye begins his account by proposing an account of the unity of experience at a single time; this account is extended over the succeeding chapters to cover bodily sensations at a single time and perceptual experience, bodily sensations, conscious thoughts, and felt moods at a single time. Tye follows these chapters with a discussion of the unity of experience through time. Turning to the split-brain phenomenon, he proposes an account of the mental life of split-brain subjects and argues that certain facts about these subjects offer support for his theory of unity. Finally, addressing the topic of the nature of persons and personal identity, Tye finds the two great historical accounts -- the ego theory and the bundle theory -- lacking and he makes an alternative proposal. He includes an appendix on the general representational approach to consciousness and its many varieties, because of the relevance of representationalism to the theory of unity being adanced. (shrink)

Conscious experience is one of the most difficult and thorny problems in psychological science. Its study has been neglected for many years, either because it was thought to be too difficult, or because the relevant evidence was thought to be poor. Bernard Baars suggests a way to specify empirical constraints on a theory of consciousness by contrasting well-established conscious phenomena - such as stimulus representations known to be attended, perceptual, and informative - with closely comparable unconscious ones - such (...) as stimulus representations known to be preperceptual, unattended, or habituated. Adducing data to show that consciousness is associated with a kind of global workplace in the nervous system, and that several brain structures are known to behave in accordance with his theory, Baars helps to clarify many difficult problems. (shrink)

Neil Levy presents a new theory of freedom and responsibility. He defends a particular account of consciousness--the global workspace view--and argues that consciousness plays an especially important role in action. There are good reasons to think that the naïve assumption, that consciousness is needed for moral responsibility, is in fact true.

The elephant in the room -- Crabs and octopuses -- The central intelligence of a frog -- The cerebral cortex and consciousness -- Social consciousness -- Yoda and Darth: how can we find -- Consciousness in the brain? -- The hard problem and other perspectives on consciousness -- Conscious machines -- Uploading minds -- How to build visual consciousness.

Can we consciously see more items at once than can be held in visual working memory? This question has elud- ed resolution because the ultimate evidence is subjects’ reports in which phenomenal consciousness is filtered through working memory. However, a new technique makes use of the fact that unattended ‘ensemble prop- erties’ can be detected ‘for free’ without decreasing working memory capacity.

In a new study, Ben-Haim et al. use subliminal stimuli to separate conscious and unconscious perception in macaques. A programme of this type, using a range of cognitive tasks, is a promising way to look for conscious perception in more controversial cases.

A further development of Tye's theory of phenomenal consciousness along with replies to common objections.

The significance of consciousness in modern science is discussed by leading authorities from a variety of disciplines. Presenting a wide-ranging survey of current thinking on this important topic, the contributors address such issues as the status of different aspects of consciousness; the criteria for using the concept of consciousness and identifying instances of it; the basis of consciousness in functional brain organization; the relationship between different levels of theoretical discourse; and the functions of consciousness.