“There remains the inescapable truth about perception: the positivity of all experience at every moment of it. As John Cage has insisted, ‘there is no such thing as silence. Something is always happening that makes a sound.’ (Cage has described how, even in a soundless chamber, he still heard at least two things: his heartbeat and the coursing of the blood in his head). Similarly, there is no such thing as empty space. As long as a human eye is looking there is always something to see. To look at something that’s ’empty’ is still to be looking, still to be seeing something — if only the ghosts of one’s own expectations. In order to perceive fullness, one must retain an acute sense of the emptiness which marks it off; conversely, in order to perceive emptiness, one must apprehend other zones of the world as full.” – Susan Sontag, “The Aesthetics of Silence”