Daniel Dennett’s Consciousness Explained is probably the most widely read book about consciousness ever written by a philosopher. Despite this, the book has had a surprisingly small influence on how most philosophers of mind view consciousness. This might be because many philosophers badly misunderstand the book. They claim it does not even attempt to explain consciousness, but instead denies its very existence. Outside of philosophy the book has had more influence, but is saddled by the same misunderstanding. Now, 30 years (...) after publication, Consciousness Explained deserves reconsideration from anyone interested in consciousness. Here I make a case for this. To start, I will clear up the central misunderstanding of the book. With that done, I will explain and update Dennett’s tantalizing approach to consciousness and the mind. The result brings us very, very close to explaining consciousness. Or so I will argue. (shrink)

This book proposes a theory of human cognitive evolution, drawing from paleontology, linguistics, anthropology, cognitive science, and especially neuropsychology. The properties of humankind's brain, culture, and cognition have coevolved in a tight iterative loop; the main event in human evolution has occurred at the cognitive level, however, mediating change at the anatomical and cultural levels. During the past two million years humans have passed through three major cognitive transitions, each of which has left the human mind with a new way (...) of representing reality and a new form of culture. Modern humans consequently have three systems of memory representation that were not available to our closest primate relatives: mimetic skill, language, and external symbols. These three systems are supported by new types of “hard” storage devices, two of which (mimetic and linguistic) are biological, one technological. Full symbolic literacy consists of a complex of skills for interacting with the external memory system. The independence of these three uniquely human ways of representing knowledge is suggested in the way the mind breaks down after brain injury and confirmed by various other lines of evidence. Each of the three systems is based on aninventivecapacity, and the products of those capacities – such as languages, symbols, gestures, social rituals, and images – continue to be invented and vetted in the social arena. Cognitive evolution is not yet complete: the externalization of memory has altered the actual memory architecture within which humans think. This is changing the role of biological memory and the way in which the human brain deploys its resources; it is also changing the form of modern culture. (shrink)

In Feeling of Knowing cases, subjects have a form of consciousness about the presence of a content (such as an item of information) without having access to it. If this phenomenon can be correctly interpreted as having to do with consciousness, then there would be a P-conscious mental experience which is dissociated from access.

The study of sleep and wakefulness can inform debates about the nature of consciousness. We argue that sleep and wakefulness fall along a multidimensional continuum and that inconsistencies and paradoxes with the accounts put forth by Merker et al. and Tononi can be understood in terms of a pervasive false dichotomy between these two states.

Some cases of prosopagnosia involve a highly circumscribed loss of A-consciousness. When seen in this way they offer further support for the arguments made in Block's target article.

Each of our sensory modalities—vision, touch, taste, etc.—works on a slightly different timescale, with differing temporal resolutions and processing lag. This raises the question of how, or indeed whether, these sensory streams are co-ordinated or ‘bound’ into a coherent multisensory experience of the perceptual ‘now’. In this paper I evaluate one account of how temporal binding is achieved: the temporal windows hypothesis, concluding that, in its simplest form, this hypothesis is inadequate to capture a variety of multisensory phenomena. Rather, the (...) evidence suggests the existence of a more complex temporal structure in which multiple overlapping windows support distinct functional mechanisms. To aid in the precise formulation of such views, I propose a taxonomy of temporal window types and their characteristics that in turn suggests promising avenues for future empirical and philosophical research. I conclude by examining some philosophical implications of multi-window models for the metaphysics of perception and perceptual experience more generally. (shrink)

In physics, the temporal dimension has units of infinitesimally brief duration. Given this, how is it possible to perceive things, such as motion, music, and vibrotactile stimulation, that involve extension across many units of time? To address this problem, it is proposed that there is what is termed an “information construct of happening” (ICOH), a simultaneous representation of recent, temporally differentiated perceptual information on the millisecond time scale. The main features of the ICOH are (i) time marking, semantic labeling of (...) all information in the ICOH with ordinal temporal information and distance from what is informationally identified as the present moment, (ii) vector informational features that specify kind, direction, and rate of change for every feature in a percept, and (iii) connectives, information relating vector informational features at adjacent temporal locations in the ICOH. The ICOH integrates products of perceptual processing with recent historical information in sensory memory on the subsecond time scale. Perceptual information about happening in informational sensory memory is encoded in semantic form that preserves connected semantic trails of vector and timing information. The basic properties of the ICOH must be supported by a general and widespread timing mechanism that generates ordinal and interval timing information and it is suggested that state‐dependent networks may suffice for that purpose. Happening, therefore, is perceived at a moment and is constituted by an information structure of connected recent historical information. (shrink)

Block has attempted to reduce the confusion and controversy concerning the term “consciousness” by suggesting that there are two forms or types of consciousness, each of which has several characteristics or properties. This suggestion appears to further becloud the topic, however. Perhaps consciousness cannot be defined adequately and should not be considered as a topic that can be studied scientifically.

While we perceive events in our environment through multiple sensory systems, we nevertheless perceive all of these events as occupying a single unified timeline. Time, as we perceive it, is unified. I argue that existing accounts of the perceived unity of time fail. Instead, the perceived unity of time must be constructed by integrating our initially fragmented timekeeping capacities. However, existing accounts of multimodal integration do not tell us how this might occur. Something new is needed. I finish the paper (...) by articulating the hurdles that must be overcome to provide an account of the perceived unity of time. (shrink)

This commentary elaborates on Gray's conclusion that his neurophysiological model of consciousness might explain how consciousness arises from the brain, but does not address how consciousness evolved, affects behaviour or confers survival value. The commentary argues that such limitations apply to all neurophysiological or other third-person perspective models. To approach such questions the first-person nature of consciousness needs to be taken seriously in combination with third-person models of the brain.

Investigations of the function of consciousness in human information processing have focused mainly on two questions: (1) where does consciousness enter into the information processing sequence and (2) how does conscious processing differ from preconscious and unconscious processing. Input analysis is thought to be initially "preconscious," "pre-attentive," fast, involuntary, and automatic. This is followed by "conscious," "focal-attentive" analysis which is relatively slow, voluntary, and flexible. It is thought that simple, familiar stimuli can be identified preconsciously, but conscious processing is needed (...) to identify complex, novel stimuli. Conscious processing has also been thought to be necessary for choice, learning and memory, and the organization of complex, novel responses, particularly those requiring planning, reflection, or creativity. (shrink)

This reply to five continuing commentaries on my 1991 target article on “Is human information processing conscious” focuses on six related issues: 1) whether focal attentive processing replaces consciousness as a causal agent in third-person viewable human information processing, 2)whether consciousness can be dissociated from human information processing, 3) continuing disputes about definitions of "consciousness" and about what constitutes a “conscious process” , 4) how observer-relativity in psychology relates (and does not relate) to relativity in physics, 5) whether the first-person (...) viewable causal efficacy of consciousness counts as ‘real’ causal efficacy and 6) a clarification of the sense in which first- and third-person causal accounts of mental processing are complementary and mutually irreducible. (shrink)

This paper replies to the first 36 commentaries on my target article on “Is human information processing conscious?” (Behavioral and Brain Sciences,1991, pp.651-669). The target article focused largely on experimental studies of how consciousness relates to human information processing, tracing their relation from input through to output, while discussion of the implications of the findings both for cognitive psychology and philosophy of mind was relatively brief. The commentaries reversed this emphasis, and so, correspondingly, did the reply. The sequence of topics (...) in the reply roughly follows that of the target article. The discussion begins with a reconsideration of the details of the empirical findings, whether they can be extrapolated to non-laboratory settings, and the extent to which one can rely on their use of subjective reports. This is followed by an in-depth discussion of what is meant by “conscious processing” and of how phenomenal consciousness relates to attentional processing. We then turn to broader philosophical and theoretical issues. I point out some of the reasons why I do not support epiphenomenalism, dualist-interactionism, or reductionism, and elaborate on how first- and third-person views of the mind can be regarded as complementary and mutually irreducible. I suggest how the relation of conscious experiences to their neural correlates can be understood in terms of a dual-aspect theory of information,and how this might be used to resolve some of the paradoxes surrounding the causal interactions of consciousness and brain. I also suggest that, viewed from a first-person perspective, consciousness gives purpose to existence, which allows a different way of viewing its role in evolution. (shrink)

The conclusions drawn by Benjamin Libet from his work with collegues on the timing of somatosensorial conscious experiences has met with a lot of praise and criticism. In this issue we find three examples of the latter. Here I attempt to place the divide between the two opponent camps in a broader perspective by analyzing the question of the relation between physical timing, neural timing, and experiential timing. The nervous system does a sophisticated job of recombining and recoding messages from (...) the sensorial surfaces and if these processes are slighted in a theory, it might become necessary to postulate weird operations, including subjective back-referral. Neuroscientifically inspired theories are of necessity still based on guesses, extrapolations, and philosophically dubious manners of speech. They often assume some neural correlate of consciousness as a part of the nervous system that transforms neural activity in reportable experiences. The majority of neuroscientists appear to assume that the NCC can compare and bind activity patterns only if they arrive simultaneously at the NCC. This leads to a search for synchrony or to theories in terms of the compensation of differences in neural delays . This is the main dimension of the Libet discussion. Examples from vision research, such as “temporal-binding-by-synchrony” and the “flash-lag” effect, are then used to illustrate these reasoning patterns in more detail. Alternatively one could assume symbolic representations of time and space that are not coded in their own dimension . Unless such tags are multiplexed with the quality message , one gets a binding problem for tags. One of the hidden aspects of the discussion between Libet and opponents appears to be the following. Is the NCC smarter than the rest of the nervous system, so that it can solve the problems of local sign and timing on its own, or are these pieces of information coded symbolically early on in the system? A supersmart NCC appears to be the assumption of Libet's camp . The wish to distribute the smartness evenly across all stages of processing in the nervous system appears to motivate the opponents. I argue that there are reasons to side with the latter group. (shrink)

Blocks distinction between “phenomenal feel” consciousness and “thought/cognition” consciousness is a cultural construction. Consciousness (and its “subspecies”) is not a natural kind. Some crosscultural data are presented to support this.

On the basis of neuropsychological evidence, it is clear that attention should be given a role in any model of consciousness. What is known about the many instances of dissociation between explicit and implicit knowledge after brain damage suggests that conscious experience might not be linked to a restricted area of the brain. Even if it were true that there is a single brain area devoted to consciousness, the subicular area would seem to be an unlikely possibility.

It is argued that there is no fallacy in the reasoning in the example of the thirsty blindsight subject, on one reconstruction of that reasoning. Neither the case of orgasm nor the case of a visual versus an auditory experience as of something overheard shows that phenomenal content is not representational.

Any theoretician constructing a serious model of consciousness should carefully assess the details of empirical data generated in the neurosciences and psychology. A failure to account for those details may cast doubt on the adequacy of that model. This paper presents a case in point. Dennett and Kinsbourne's (Dennett, D., & Kinsbourne, M. (1992). Time and the observer: The where and when of consciousness in the brain. Behavioral and Brain Sciences, 15, 183-243) assault on the materialist version of the Cartesian (...) Theater model of the mind relies significantly on the superiority of their Multiple Drafts model of consciousness as an explanation of the phenomenon of metacontrast. However, their description of metacontrast is, in important ways, inadequate. The result is that their explanation of how the Multiple Drafts model handles this phenomenon fails to account for the actual data. In this paper I offer a more complete description of metacontrast, show how Dennett and Kinsbourne's explanation fails, and argue that there are good theoretical reasons for choosing the so-called Stalinesque model over the so-called Orwellian model. (shrink)

An active role for conscious processes in the production of behaviour is proposed, involving top level controls in a hierarchy of behavioural control. It is suggested that by inhibiting or sensitizing lower levels in the hierarchy conscious processes can play a role in the organization of ongoing behaviour. Conscious control can be more or less evident, according to prevailing circumstances.

. I sketch a synthetic integration of several levels of explanation in addressing how myths, narratives, and stories engage human beings, produce their sense of identity and self‐understanding, and shape their intellectual, emotional, and embodied lives. Ultimately it is our engagement with the metanarratives of religious imagination by which we address a set of existentially necessary but ontologically unanswerable metaphysical questions that form the basis of religious belief. I show how a multileveled understanding of evolutionary biology, history, neuroscience, psychology, narrative, (...) and mythology may form a coherent picture of the human spirit. Neuropsychological functions involved in constructing and responding to the narratives by which we form our identities and build meaningful lives include memory, attention, emotional marking, and temporal sequencing. It is the neural substrate, the emotional shaping, and the narrative structuring of higher cognitive function that provide the sine qua non for the construction of meaning, relationship, morality, and purpose that extend beyond our personal boundaries, both spatial and temporal. This includes a neural affect system shaped by our developmental dependency, the dynamic narratives of self formed in the development of identity and reconstructed over the life span, drawing on culturally available mythic and storied forms. Narrative constitutes our movement in moral space and may have the potential both for healing and for disruption for us as individuals and as a species, providing a contingent solution to the alienation and fragmentation of personhood, relationship, and community. (shrink)

Gray extrapolates from circuit models of psychopathology to propose neural substrates for the contents of consciousness. I raise three concerns: knowledge of synaptic arrangements may be inadequate to fully support his model; latent inhibition deficits in schizophrenia, a focus of this and related models, are complex and deserve replication; and this conjecture omits discussion of the neuropsychological basis for the contents of the unconscious.

The new methods of modern sciences can contribute to understand the genesis of mental illness, the disturbances in brain chemistry, physiology, anatomy or genetical information underlying different diseases of the nervous system. Understanding mental illness is not only challenging to science, but is also of great social importance. Moreover, the new developments of neurosciences put new lights on discussions such as brain-mind concepts, unity of mind, definition of consciousness and even definition of the person.For the majority of the scientists, it (...) is clear today that the mind can not be conceived any more as unique and indivisible. For philosophers, it is clear also that neuroscience influenced their vision of life and death: neurosciences are not strange to the debate whole-body death versus whole-brain death for instance. Modern scientific achievements have expanded our vision, allowing us to percieve previously unanticipated interrelationships between biological and psychological phenomena. The boundary between some behavioural and higher neural function studies and biology is arbitrary and changing. It has been imposed not by the natural contours of the disciplines, but by lack of knowledge. (shrink)

Gray unwisely melds together two distinguishable contributions of consciousness: one to epistemology, the other to evolution. He also renders consciousness needlessly invisible behaviorally.