Stop reading and concentrate on the noises around you,
the noises you weren’t conscious of until a few seconds ago. You may be in a quiet room, but you’ll still detect the sound of some distant equipment, a rustling, a humming, voices—some close, some farther away—whose words you can’t make out but are there. And you’ll become aware of the movements, the vibrations produced by your body: your breathing, your heartbeat, the gurgling of your digestive system.