Ned Block

This is a charming and engaging book that combines careful attention to the phenomenology of experience with an appreciation of the psychology and neuroscience of perception. In some of its aimsfor example, to show problems with a rigid version of a view of visual perception as an inverse optics process of constructing a static 3-D representation from static 2-D information on the retina--it succeeds admirably. As No points out, vision is a process that depends on interactions between the perceiver and the environment and involves contributions from sensory systems other than the eye. He is at pains to note that vision is not passive. His analogy with touch is to the point: touch involves skillful probing and movement, and so does vision, although less obviously and in my view less centrally so. This much is certainly widely accepted among vision scientistsalthough mainstream vision scientists (represented, for example, by Stephen Palmers excellent textbook²) view these points as best seen within a version of the inverse optics view that takes inputs as non-static and as including motor instructions (for example, involving eye movements and head movements).³ The kind of point that No raises is viewed as important at the margins, but as not disturbing the main lines of the picture of vision that descendswith many changesfrom the pioneering work of David Marr in the 1980s (and before him, from Helmholtz). But No shows little interest in mainstream vision science, focusing on non-mainstream ideas in the science of perception, specifically ideas from the anti-representational psychologist J.J. Gibson, and also drawing on Wittgenstein and the phenomenology tradition. There is a sense throughout the book of revolution, of upsetting the applecart. This is a review from the point of view of the applecart.

One of the most important issues concerning the foundations ofconscious perception centerson thequestion of whether perceptual consciousness is rich or sparse. The overflow argument uses a form of ‘iconic memory’ toarguethatperceptual consciousnessisricher (i.e.,has a higher capacity) than cognitive access: when observing a complex scene we are conscious of more than we can report or think about. Recently, the overflow argumenthas been challenged both empirically and conceptually. This paper reviews the controversy, arguing that proponents of sparse perception are committed to the postulation of (i) a peculiar kind of generic conscious representation that has no independent rationale and (ii) an unmotivated form of unconscious representation that in some cases conflicts with what we know about unconscious representation.

This volume of Ned Block's writings collects his papers on consciousness, functionalism, and representationism. A number of these papers treat the significance of the multiple realizability of mental states for the mind-body problem -- a theme that has concerned Block since the 1960s. One paper on this topic considers the upshot for the mind-body problem of the possibility of a robot that is functionally like us but physically different -- as is Commander Data of _Star Trek's_ second generation. The papers on consciousness treat such conceptual issues as phenomenal versus access consciousness, Dennett's theory of consciousness, and the function of consciousness, as well as such empirical matters as "How Not to Find the Neural Correlate of Consciousness," and an argument that there are distinct neural correlates for access consciousness and phenomenal consciousness. Turning to the mind-body problem, Block defends physicalism against Max Black's argument concerning phenomenal modes of presentation. The papers on representationism consider "mental paint" as well as the "Inverted Earth" thought experiment -- a world in which colors are reversed but there is a compensating reversal in the words that are used to describe them. _Consciousness, Function, and Representation_, bringing together papers that have appeared primarily in journals and conference proceedings, can be regarded as Block's most complete statement of his positions on consciousness