Our world is brimming with sound: from the detonation of distant thunder to the drip, drip drip of a rusty drainpipe. Once we've been shown how to listen more attentively and creatively, we can access a deeper, more lasting meditation. Our thoughts, dreams and daydreams might be carried along a stream of birdsong, or punctuated by a rush of unexpected laughter. Learning about sound--where, how and why it comes into being--is learning about the...