From Philip Glass, again, Words Without Music: “The accepted idea when I was growing up was that the late Beethoven quartet or The Art of the Fugue or any of the great masterpieces had a platonic identity — that they had an actual, independent existence. What [John] Cage was saying is that there is no such thing as an independent existence. The music exists between you — the listener — and the object that you’re listening to. The transaction of it coming into being happens through the effort you make in the presence of that work. The cognitive activity is the content of the work.”
This affirms the idea of art being a form of communication, and that the full realization of a act of such communication is the exchange with the reader/observer/listener.
He goes on to talk about the role of the performer, identifying the performer as also being a part of the transaction. He states that the role of the listener is to listen, and that that is also the activity of the composer, and of the performer. He says, “A performance becomes a formal framing of the activity of listening…” and “The ideal way of performing…would be when the performer allows the activity of playing to be shaped by the activity of listening, and perhaps even by the activity of imagining listening.” I take this to mean not self-listening as “how am I doing,” but listening as “what is the music demanding me to convey in this moment.” This idea can be as relevant for a poetry reading as for a concert.