No mental phenomenon is more central than consciousness to an adequate understanding of the mind. Nor does any mental phenomenon seem more stubbornly to resist theoretical treatment. Consciousness is so basic to the way we think about the mind that it can be tempting to suppose that no mental states exist that are not conscious states. Indeed, it may even seem mysterious what sort of thing a mental state might be if it is not a conscious state. On this way (...) of looking at things, if any mental states do lack consciousness, they are exceptional cases that call for special explanation or qualification. Perhaps dispositional or cognitive states exist that are not conscious, but nonetheless count as mental states. (shrink)

Voluntary acts are preceded by electrophysiological (RPs). With spontaneous acts involving no preplanning, the main negative RP shift begins at about200 ms. Control experiments, in which a skin stimulus was timed (S), helped evaluate each subject's error in reporting the clock times for awareness of any perceived event.

An extended examination of Libet's works led to a comprehensive reinterpretation of his results. According to this reinterpretation, the Minimum Train Duration of electrical brain stimulation should be considered as the time needed to create a brain stimulus efficient for producing conscious sensation and not as a basis for inferring the latency for conscious sensation of peripheral origin. Latency for conscious sensation with brain stimulation may occurafterthe Minimum Train Duration. Backward masking with cortical stimuli suggests a 125-300 ms minimum value (...) for the latency for conscious sensation of threshold skin stimuli. Backward enhancement is not suitable for inferring this latency. For determining temporal relations between stimuli that correspond to subjects' reports, theendof cerebral Minimum Train Duration should be used as reference, rather than its onset. Results of coupling peripheral and cortical stimuli are explained by a latency after the cortical Minimum Train Duration, having roughly the same duration as the latency for supraliminal skin stimuli. Results of coupling peripheral stimuli and stimuli to medial lemniscus (LM) are explained by a shorter LM latency and/or a longer peripheral latency. This interpretation suggests a 230 ms minimum value for the latency for conscious sensation of somatosensory near-threshold stimuli. The backward referral hypothesis, as formulated by Libet, should not be retained. Long readiness potentials preceding spontaneous conscious or nonconscious movements suggest that both kinds of movement are nonconsciously initiated. The validity of Libet's measures of W and M moments (Libet et al., 1983a) is questionable due to problems involving latencies, training, and introspective distinction of W and M. Veto of intended actions may be initially nonconscious but dependent on conscious awareness. (shrink)

The prima facie heterogeneity between psychical and physical phenomena seems to be a serious objection to psychoneural identity thesis, according to many authors, from Leibniz to Popper. It is argued that this objection can be superseded by a different conception of consciousness. Consciousness, while being conscious of something, is always unconscious of itself . Consciousness of being conscious is not immediate, it involves another, second-order, conscious state. The appearance of mental states to second-order consciousness does not reveal their true nature. (...) Psychoneural identity can thus be considered a valid hypothesis. Related views of Kant, Freud, Shaffer, Bunge and others are considered. “Naive psychical realism” is criticised. Consciousness of mental events is considered as the result of the action of a cerebral system that observes the neural events hypothetically identical to mental events. The theory combines a materialist view with a due consideration of subjective experience. (shrink)

First published in 2002. Routledge is an imprint of Taylor & Francis, an informa company.

What is mind? This book attempts to give a philosophical answer to that question in language accessible to the layperson, but with a rigor acceptable to the specialist. Published on the centenary of the birth of Wittgenstein and the 40th anniversary of the publication of Gilbert Ryle 's classic The Concept of Mind, this work testifies to the influence of those thinkers on Kenny's own work in the philosophy of mind, and assembles Kenny's ideas on philosophical psychology into a systematic (...) whole. (shrink)

This thesis explores the possibility of theoretically conceiving consciousness as an activity of the brain. Objections, based on the concept of qualia, to the identification of consciousness with a brain activity are refuted. Phenomenal consciousness is identified with access-consciousness. Consciousness is conceived as a higher order processing of informational states of the brain. The state of consciousness represents an integration of prior nonconscious states. Libet’s research on the timing of conscious experience is reviewed and analyzed. His hypothesis of backward referral (...) is rejected. Since specific brain activity (the readiness potential) precedes the conscious intention, the implications of this fact on the concepts of volition and free will are discussed. Non-deliberate voluntary acts are performed without a prior consciousness of the intention to perform them. Conversely, the decision to perform a deliberate act is influenced by consciousness of the intention. Free will is viewed as compatible with the causal determination of mental processes. The theory is successfully applied to the different contents of consciousness: consciousness of perceptions, of bodily sensations, of actions, of memories, of ideas, of thoughts, of language, of affective states, of beliefs, of desires, of oneself and consciousness of being conscious. The relation between the theory of consciousness and psychoanalysis is also explored. Psychoanalysis is seen as compatible with the proposed theory, which is able to enlighten some aspects of the process of becoming conscious in psychoanalytic treatment. The general approach is interdisciplinary : the theory must take into account constraints derived from philosophy, neurophysiology, psychology, neuropsychology, etc. Consciousness is conceived, not as a property of some mental states, but as a specific higher-order activity, based on lower-order nonconscious activities. (shrink)

[opening paragraph] -- Clark: The `astonishing hypothesis' which you put forward in your book, and which you obviously feel is very controversial, is that `You, your joys and sorrows, your memories and ambitions, your sense of personal identity and free will are, in fact, no more than the behaviour of a vast assembly of nerve cells. As Lewis Carroll's Alice might have phrased it: `You're nothing but a pack of neurons'.' But it seems to me that this is not so (...) astonishing a statement for a scientist to make. Isn't this what reductionist science has always believed? (shrink)

Recent experiments performed by Benjamin Libet, a brain physiologist, have raised an interesting problem about the role of conscious decisions in the production of a simple voluntary movement. We ordinarily believe that, in many circumstances, the conscious decision to perform a simple action matters for the performance of that action. But, Libet has shown that by the time a person "freely" decides to flex her wrist, the distinctive brain processes that cause the movement to occur are already well under way. (...) He asked his subjects to perform a simple wrist movement "at will" and timed the occurrence of their conscious decision to move. What he found was that the chain of events that are to cause the movement are nearly complete before the subject is ever aware that she is about to move. ;I discuss and criticize both Libet's own philosophically charged solution to this problem and some of the other views, including Daniel Dennett's, that have been advanced in the recent literature on Libet's experiments. I argue that all of these responses to the problem are inadequate because they are based on mistaken assumptions about the nature of consciousness. I offer my own solution to the paradox, which is based on a more adequate theory of consciousness, one drawn in part from the work of D. M. Armstrong, and I assess some putative objections to this theory. (shrink)

The paper begins by contrasting the unitary nature of conscious experience with the demonstrable localization of neural events. Philosophers and neuroscientists have developed models to account for this paradox, but they have yet to be tested empirically. The author proposes a `Conscious Mental Field', which is produced by, but is phenomenologically distinct from, brain activity. The hypothesis is, in principle, open to experimental verification. The paper suggests appropriate surgical procedures and some of the difficulties that would need to be overcome (...) in such an experiment. (shrink)