A HISTORY OF THE MIND

Actually, not a history of the mind, but a theory of consciousness--and an amazingly parsimonious theory at that. Consciousness, contends experimental psychologist Humphrey, is nothing but the having of sensations--sensations that have become internalized and are the origin of ""actions"" that transform the universe. Looking at the setting sun over Cambridge (England), Humphrey says, ""I am representing the light arriving at my retina aa a circular patch of redness happening to me and aa a fiery orb existing in the galaxy."" All the while he is living in a continuous present, a persistence of time accompanied by reverberating cerebral ""sentiments."" To arrive at this theory, Humphrey begins with the hypothesis that sensation and perception are separate--that there are two independent channels in the brain rather than a serial order in which, for example, perception follows sensation. Humphrey's championing of the separatist approach involves a discourse on evolution aa well aa the elaboration of experiments in which blind subjects (i.e., devoid of visual sensations) learned visual perception by virtue of having a tiny TV camera image translated to vibrations on a patch of skin. All this is very interesting, and smartly, wittily told: Humphrey has a marvelous repertoire of quotes and anecdotes that make for pleasurable reading. But is the theory convincing? The reader armed with perceptual memory, the daydreamer, and the mind engaged in mentally providing a theorem are not living in a sensory mode engaged in contact with the world, but all enjoy some degree of consciousness. Moreover, what can be said of neuroscience, with its cells and circuitry? If there are dual circuits separating sensation from perception, let's see them. Only then, perhaps, could one argue that Humphrey has developed a new theory of perception--not a touchy-feely one--to explain consciousness.