Scientific and philosophical perspectives on hallucination: essays that draw on empirical evidence from psychology, neuroscience, and cutting-edge philosophical theory.

We present a new account of perceptual consciousness, one which gives due weight to the epistemic commitment of normal perception in familiar circumstances. The account is given in terms of a higher-order attitude for which the subject has an immediate perceptual epistemic warrant in the form of an appropriate first-order perception. We develop our account in contrast to Rosenthal's higher-order account, rejecting his view of consciousness in virtue of so-called ‘targetless’ higher-order states. We explain the key notion of an immediate (...) perceptual warrant and show both that it requires the content of the higher-order attitude to match that of the first-order perception, and also that it gives a new perspective on the intimate relationship, rightly emphasised by Rosenthal, between consciousness and a subject's testimony as to ‘how it is with her’. (shrink)

How can the fine-grained phenomenology of conscious experience arise from neural processes in the brain? How does a set of action potentials (nerve impulses) become like the feeling of pain in one's experience? Contemporary neuroscience is teaching us that our mental states correlate with neural processes in the brain. However, although we know that experience arises from a physical basis, we don't have a good explanation of why and how it so arises. The problem of how physical processes give rise (...) to experience is called the 'hard problem' of consciousness and it is the contemporary manifestation of the mind-body problem. This book explains the key concepts that surround the issue as well as the nature of the hard problem and the several approaches to it. It gives a comprehensive treatment of the phenomenon incorporating its main metaphysical and epistemic aspects, as well as recent empirical findings, such as the phenomenon of blindsight, change blindness, visual-form agnosia and optic ataraxia, mirror recognition in other primates, split-brain cases and synaesthesia. (shrink)

This book explains the key concepts that surround the issue as well as the nature of the hard problem and the several approaches to it. It gives a comprehensive treatment of the phenomenon, incorporating its main metaphysical and epistemic aspects as well as recent empirical findings, such as the phenomena of blindsight, change blindness, visual-form agnosia and optic ataxia, mirror recognition in other primates, split-brain cases, and visual extinction.

According to some representationalists (M. Tye, Ten problems of consciousness, MIT Press, Massachusetts, USA, 1995; W.G. Lycan, Consciousness and experience, MIT Press, Cambridge, Massachusetts, USA, 1996; F. Dretske, Naturalising the mind, MIT Press, Massachusetts, USA 1995), qualia are identical to external environmental states or features. When one perceives a red rose for instance, one is visually representing the actual redness of the rose. The represented redness of the rose is the actual redness of the rose itself. Thus redness is not (...) a property of one’s experience but an externally constituted property of the perceived physical object. In this sense, qualia are out there, in the external world. Here, I argue that the main representationalist arguments to this effect, if successful, establish no more than a symmetrical supervenience relation between representational content and qualia, and that a supervenience relation alone (albeit symmetrical) doesn’t suffice for identity. This supervenience thesis between qualia and representational content leaves open the question as to the essential nature of qualia. (shrink)

In this paper I point out main shortfalls of the three main families of theories of perception and I propose a sort of inferential realism. In addition, I argue that there cannot be a scientific variant of direct realism and illustrate this point with reference to P.F.Strawson's attempt to reconcile, not naïve realism and the scientific variant as he amounts to, but rather, direct and indirect realism. I draw the distinction between four cases of illusion, and I refer to one (...) of these, namely to the case of veridical illusion, to show that Strawson's view, put in terms of the Fregean sense-reference distinction, fails. As regards indirect realism, I argue against the representationalist account and the Lockean picture of primary and secondary qualities. Phenomenalism is rejected in terms of the impossibility to identify an object throughout different contexts and I suggest that what is for x to be that x in different contexts can be given only by a realist analysis of a material object. Finally, I provide an account of what it is for A to perceive that x with respect to different contexts and I conclude with what conditions should veridical perception meet and therefore propose the framework of a new theory of perception. (shrink)