51动漫

Consciousness

by Rita Carter, Weidenfeld & Nicolson, 拢20, ISBN 030435600X

YOU focused on the words on this page before you decided to do so: a paradox that throws into question what the word 鈥測ou鈥� might refer to. Reading about consciousness always brings up self-referential strangeness like this. Yet in Consciousness Rita Carter successfully introduces the richness and dynamism of consciousness studies today.

First come some findings of neuroscience and psychology that deconstruct ordinary notions about conscious experience. These include our blindness to gross changes in a scene when we鈥檙e briefly distracted (51动漫, 22 June, p 26) and, conversely, the perceptual 鈥渇illing in鈥� of features we don鈥檛 actually see. Other experiments indicate that our consciousness experience routinely lags behind actual events by a fifth of a second. We 鈥渂ackdate鈥� and even reverse the 鈥渙bjective鈥� order of events.

Having set the stage for what she calls 鈥渁 stream of illusion鈥�, Carter moves to the so-called 鈥渉ard problem鈥� of explaining the existence of consciousness in a material universe. Consciousness appears to have subjective properties that do not appear in unconscious matter. These include the 鈥渓ook鈥� of red 鈥� as distinguished from the physical processes that may trigger it. Philosophers call these qualia.

Nothing in the physical sciences seems capable even of describing qualia, let alone implying their existence. This makes it very hard to understand scientifically how consciousness could ever have arisen. The problem has proven so intractable that some serious investigators suggest that consciousness must be added to the list of fundamental non-derived properties of the Universe.

Carter presents all sides of major issues in a style that is lively, engaging and often entertaining. She supplements her own clear language with more than a dozen pieces by leading thinkers from such relevant disciplines as neuroscience, psychology, philosophy, artificial intelligence and physics. One of the many strengths of the book is how clearly she explains the many, often surprising, implications of discoveries in neuropsychology for our ordinary notions of perception, free will and morality.

The scope of Consciousness is broad: it also covers neural networks, the role of body awareness in experience and thought, the nature of 鈥渟elf鈥�, the implications of schizophrenia and other kinds of 鈥渇ractured鈥� consciousness, and meditation.

So it is not surprising that some problems of consistency arise. For example, Carter suggests that 鈥渕apping of movement effects鈥� in the sensory areas of the brain provides the initial 鈥渁wareness of awareness鈥� that originally produced 鈥減ure qualia鈥�. But this major claim seems inconsistent with her earlier suggestions that mapping and information feedback can take place in non-conscious computing machines, and unconsciously in humans, without either qualia or any other sort of consciousness being present at all. But such questions about Carter鈥檚 own, avowedly tentative theories should provide for discussion.

Also in places Carter leaves out points that are both highly relevant and well known to experts. Her discussion of the 鈥渦nity of self鈥�, for example, ignores a central aspect of the notion that is held in common by philosophers whose views are as strongly opposed as David Hume and Immanuel Kant. And her theorising about the physical basis and possible significance of mystical experiences appears to be based on only a few studies of particular meditation techniques. She passes over the considerable literature on other, very different procedures, including transcendental meditation 鈥� the technique that is most widely researched, as I know from my own work.

But Consciousness is a treasure trove of fact, argument and opinion, doing an excellent job of conveying both research and controversies. The general reader will find it filled with stimulating material, and it makes a fine textbook for consciousness studies.