A SECOND WAY OF KNOWING

In spite of the New Age-ish title, the latest from Bolles (Remembering and Forgetting, 1987, etc.) attempts to put perception in proper perspective—not as a mystical phenomenon, but at the very heart of how we comprehend ourselves and the world. On the other hand, don't expect to come away with a clear idea of what perception is. Bolles is rather better at saying what it is not. So he starts off with a visit to the artificial-intelligence folks who are trying to get computers to recognize (perceive) speech and language. Not much new to report here: The machines do well by learning a particular speaker's idiosyncracies—but they can't seem to generalize. Then Bolles goes on to review what happened in psychology in the 20th century with the rise of both behaviorism and Freudianism—widely divergent schools of psychology that nevertheless share what Bolles calls a ``physicalist'' point of view that there is an objective world out there. He offers a nice discussion of Gestalt psychology, but faults that school for its naive realism. What Bolles touts instead is the brain's imparting meaning to sensations, constructing perception by analyzing neural inputs that change over time as a result of learning, attention, emotion. If this sounds nebulous, it is. If this sounds as if there's still a question of the ghost in the machine (who is aware and waiting and watching), there is. As for enlightening the reader on what is current and choice about neural coding (for pain, for example), forget it. Bolles is more concerned with putting perception on a pedestal than in telling us what it's all about. (Nine line drawings.)