Shadows.

For the beauty of the alcove is not the work of some clever device. The empty space is marked with plain wood and plain walls, so the light drawn into it forms dim shadows within emptiness. There is nothing more. And yet, when we gaze into the darkness of the crossbeam, beneath the shelves, though we know it is just shadow, we are overcome with the feeling that in this small corner of the atmosphere there reigns complete and utter silence; that here in the darkness immutable tranquility holds sway. And even as children would feel inexpressible chill as we peered into the depths of that alcove to which the sunlight had never penetrated. Where's the key to this mystery? Ultimately it is the magic of shadows. Were the shadows to be banished from its corners, the alcove would be in that instant revert to mere void.

Jun'ichirō Tanizaki