Consciousness: A User's Guide [Anglais] [Relié]

Consciousness is all the rage. It seems to pop up everywhere. It is now a legitimate subject of study. No longer can it be talked about only in nooks and crannies at conferences. One can publicly hold one of many, sometimes completely contradictory, beliefs about it. For example, one can believe that consciousness can never be understood, that it will always be private and subjective, never to be invaded by the probing, dispassionate eyes of science. Or, alternatively, one can believe that consciousness can be understood only in some mystical, noncomputational way, thereby necessitating other mysteries, such as quantum mechanics, and (when the physicists are brought in) making it even more incomprehensible. Or one can believe that consciousness is not really a problem at all; just don't look at it too long, or it will correspond to mere neural activity, suitably shuttling about in the brain circuits. If I want to learn more about my consciousness, should I go to this book? The answer is yes and no. Yes, because it is a well-written account of the wiring that makes up the brain and of the neural activities involved in the creation of consciousness. After a brief introduction to the various possible meanings of "consciousness" (e.g., awareness, being awake, mental content, and, as a different feature, self-consciousness or recognition of the self), Zeman gives a clear description of the measurements that indicate the awake state of the brain (electroencephalographic and related measurements of brain activity). Possible distortions of consciousness (e.g., pathologic changes in consciousness that occur under the influence of drugs or in a coma, trance, or similar states) are smoothly described. Vision is then analyzed, from the retina and beyond, to blindsight. The evolution of consciousness in animals is then discussed, from a Darwinian perspective. Finally, scientific theories and the nature of consciousness are considered. The more philosophical problems of other minds, of determining what it is like to be someone else, of animals' minds, and of aliens' minds, are all briefly and entertainingly described. In all, then, it was a tour de force to cram so much about this most subtle of all human experiences -- indeed, its very core -- into a reasonably sized book. But why do I then say "no" as well as "yes" to the use of this book? The answer is simple: I go to a car manual because it is written by someone who knows what a car is for -- to be driven by a working engine, with other components (such as window wipers) also working. I need the manual in case something goes wrong. If the car does not work, the manual will, I hope, tell me why not and how it might be mended, if possible on the spot. The situation is rather different with consciousness, according to this book. Zeman does not know how consciousness works. He says so succinctly, in terms of a lack of understanding of how the subtle structures of the brain (which he describes so lucidly) create consciousness: "We can see that the liquidity of water necessarily follows from the properties of the molecules of water. We lack any comparable insight into the connection between experience and the molecules of the brain. It is not yet certain that science can supply this." If science cannot, then scientific analysis of the brain may never lead us to an understanding of the uses of consciousness. Consciousness may well have all sorts of uses, such as helping us to approach God or to commune with our true quantum nature by tapping into the wave function of the universe. Zeman's suggestion -- that consciousness is part of a control circuit -- is also my way of thinking. But controlling what? One possibility, he suggests, is the control of choices among possible actions in an unpredictable world. I agree that this is one use, but surely there are many more. What about thinking? Or feeling? Moreover, Zeman's suggestion is just a guess. How can it be implemented in neural terms? If we do not know for certain how consciousness works or what it is for, how can we be sure how to advise on its use? The situation may not be as bad as all that, but Zeman misses an important area, that of diseases of consciousness. It is here that ideas about the uses of consciousness need to be tested. The most important of these diseases is schizophrenia, in which there are deep disturbances of the sense of self. I do not think that a person with schizophrenia would gain from reading this book or from knowing that his or her disappearing consciousness is needed only to help sharpen choices of actions. Something much more dramatic is happening to that person's sense of self: it becomes at times too strong, and at other times too weak. So I recommend this book to those who are beginners in the field of consciousness studies; it is a valuable contribution. But if you are a puzzled user, if you are at the end of your consciousness tether, then I am afraid you will have to wait. The user's manual is still unobtainable. John G. Taylor, Ph.D.
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. . . . Students and researchers. . . .will find his book a helpful resource. . . . Highly recommended. Upper-division undergraduates through professionals.