In my living room there are two large bookcases, each one eight feet tall, and they have about five hundred books between them. If I step up to a shelf and look at the books one by one, I can remember something about each. As a historian once said, some stare at me reproachfully, grumbling that I have never read them. One may remind me vaguely of a time when I was interested in romantic novels. An old college text will elicit a pang of unhappiness about studying. Each book has its character, and even books I know very well also have this kind of wordless flavor. Now if I step back from the shelf and look quickly across both bookcases I speed up that same process a hundredfold. Impressions wash across my awareness. But each book still looks back in its own way, answering the rude brevity of my gaze, calling faintly to me out of the corner of my eye. At that speed many books remain wrapped in the shadows of my awareness--I know I have looked past them and I know they are there, but I refuse to call them to mind.