Online research in philosophy

As far as an adequate understanding of phenomenal consciousness is concerned, representationalist theories of mind which are modelled on the information processing paradigm, are, as much as corresponding neurobiological or functionalist theories, confronted with a series of arguments based on inverted or absent qualia considerations. These considerations display the following pattern: assuming we had complete knowledge about the neural and functional states which subserve the occurrence of phenomenal consciousness, would it not still be conceivable that these neural states (or states with the same causal r.

Siewert identifies a special kind of conscious experience, phenomenal consciousness, that is the sort of consciousness missing in a variety of cases of blindsight. He then argues that phenomenal consciousness has been neglected by students of consciousness when it should not be. According to Siewert, the neglect is based at least in part on two false assumptions: (i) phenomenal features are not intentional and (ii) phenomenal character is restricted to sensory experience. By identifying an essential tension in Siewert's characterization of phenomenal consciousness, I argue that his case for denying (i) and (ii) is at best incomplete.

Phenomenal consciousness, what it is like to have or undergo an experience, is typically understood as an empirical item – an actual or possible object of consciousness. Accordingly, the problem posed by phenomenal consciousness for materialist accounts of the mind is usually understood as an empirical problem: a problem of showing how one sort of empirical item – a conscious state – is produced or constituted by another – a neural process. The development of this problem, therefore, has usually consisted in the articulation of an intuition: no matter how much we know about the brain, this will not allow us to see how it produces or constitutes phenomenal consciousness. Developing a theme first explored by Kant, and then later by Sartre, this paper argues that the real problem posed by phenomenal consciousness is quite different. Consciousness, it will be argued, is not an empirical but a transcendental feature of the world. That is, what it is like to have an experience is not something of which we are aware in the having of that experience, but an item in virtue of which the genuine (non-phenomenal) objects of our consciousness are revealed as being the way they are. Phenomenal consciousness, that is, is not an empirical object of awareness but a transcendental condition of the possibility of there being empirical objects of awareness.

O'Brien & Opie run into conceptual problems trying to equate stable patterns of neural activation with phenomenal experiences. They also seem to make a logical mistake in thinking that the brute association between stable neural patterns and phenomenal experiences implies that they are identical. In general, the authors do not provide us with a story as to why stable neural patterns constitute phenomenal experience.

In this article first some general aspects of near-death experience will be discussed, followed by questions about consciousness and its relation to brain function. Details will be described from our prospective study on near-death experience in survivors of cardiac arrest in the Netherlands, which was published in the Lancet in 2001. In this study it could not be shown that physiological, psychological, or pharmacological factors caused these experiences after cardiac arrest. Neurophysiology in cardiac arrest and in a normal functioning brain will be explained. Finally, implications for consciousness studies will be discussed, and how it could be possible to explain the continuity of our consciousness. Scientific study of NDE pushes us to the limits of our medical and neurophysiologic ideas about the range of human consciousness and mind-brain relation.

Physicalists commonly argue that conscious experiences are nothing more than states of the brain, and that conscious qualia are observer-independent, physical properties of the external world. Although this assumes the 'mantle of science,' it routinely ignores the findings of science, for example in sensory physiology, perception, psychophysics, neuropsychology and comparative psychology. Consequently, although physicalism aims to naturalise consciousness, it gives an unnatural account of it. It is possible, however, to develop a natural, nonreductive, reflexive model of how consciousness relates to the brain and the physical world. This paper introduces such a model and how it construes the nature of conscious experience. Within this model the physical world as perceived (the phenomenal world) is viewed as part of conscious experience not apart from it. While in everyday life we treat this phenomenal world as if it is the "physical world", it is really just one biologically useful representation of what the world is like that may differ in many respects from the world described by physics. How the world as perceived relates to the world as described by physics can be investigated by normal science (e.g. through the study of sensory physiology, psychophysics and so on). This model of consciousness appears to be consistent with both third-person evidence of how the brain works and with first-person evidence of what it is like to have a given experience. According to the reflexive model, conscious experiences are really how they seem.

I argue that strong representationalism, the view that for a perceptual experience to have a certain phenomenal character just is for it to have a certain representational content (perhaps represented in the right sort of way), encounters two problems: the dual looks problem and the duplication problem. The dual looks problem is this: strong representationalism predicts that how things phenomenally look to the subject reflects the content of the experience. But some objects phenomenally look to both have and not have certain properties, for example, my bracelet may phenomenally look to be circular-shaped and oval-shaped (and hence non-circular-shaped). So, if strong representationalism is true, then the content of my experience ought to represent my bracelet as being both circular-shaped and non-circular-shaped. Yet, intuitively, the content of my experience does not represent my bracelet as being both circular-shaped and non-circular-shaped. The duplication problem is this. On a standard conception of content, spatio-temporally distinct experiences and experiences had by distinct subjects may differ in content despite the fact that they are phenomenally indistinguishable. But this undermines the thesis that phenomenal character determines content. I argue that the two problems can be solved by applying a version of an idea from David Chalmers, which is to recognize the existence of genuinely centered properties in the content of perceptual experience.

Biological foundations of the psychoneural identity hypothesis are explicated and their implications discussed. "Consciousness per se" and phenomenal contents of consciousness per se are seen to be identical with events in the (unobserved) brain in accordance with Leibniz's Law, but only informationally equivalent to neural events as observed. Phenomenal content potentially is recoverable by empirical means from observed neural events, but the converse is not possible. Consciousness per se is identical with events which do not represent anything distal to sensory receptor-transducer systems. Thus, on the psychoneural identity hypothesis, consciousness per se comprises directly physical events-in-themselves rather than being a Euclidean representation of physical events as is the case for phenomenal content. After comparing consciousness per se to "onta," a paradox is suggested: rather than being irreducible to physical reality, consciousness per se is the only experience congruent with the ultimate nature of physical reality as conceived by contemporary physics.

Our heads are full of representations, according to cognitive science. It might seem inevitable that conscious states are a type of brain-based representation, but in this paper I argue that representation and consciousness each form conceptually distinct domains. Representational content depends on context, usually causal, as shown by familiar cases in which context varies while brain states do not -- twin earth cases and brains-in-vats, for example. But these same cases show that conscious content does not depend on context. The vatted brain, for example, enjoys the same experiences as its in vivo counterpart. The structure of experience -- its parts and their distinctive characters -- is the dynamic structure of the brain, viewed "from within." I call this position methodological phenomenalism (MP), and consider its prospects as a foundation for a science of consciousness. I close with a consideration of MP on the subjective "character" of conscious states. Turning away from representation dissolves the perplexity of subjectivity, leaving hopeful prospects for the scientific study of consciousness.

It is commonplace for both philosophers and cognitive scientists to express their allegiance to the "unity of consciousness". This is the claim that a subject’s phenomenal consciousness, at any one moment in time, is a single thing. This view has had a major influence on computational theories of consciousness. In particular, what we call single-track theories dominate the literature, theories which contend that our conscious experience is the result of a single consciousness-making process or mechanism in the brain. We argue that the orthodox view is quite wrong: phenomenal experience is not a unity, in the sense of being a single thing at each instant. It is a multiplicity, an aggregate of phenomenal elements, each of which is the product of a distinct consciousness-making mechanism in the brain. Consequently, cognitive science is in need of a multi-track theory of consciousness; a computational model that acknowledges both the manifold nature of experience, and its distributed neural basis.