Oto. It is thought that the five senses while indispensable are
paradoxically a barrier to satori. Sound. How does one really listen?
In Zen it is said one should see with one's ears and listen with with
one's eyes. In music it no less the space that between the notes that
is the rhythm. Try listening to the rain. The now sadly rather hackneyed
riddle of "sound of one hand clapping.".