performance

But the book of a play or the score of a symphony, however cumbered with stage-directions, expression-marks, metronome figures, and so forth, cannot possibly indicate in every detail how the work is to be performed. Tell the performer that he must perform the thing exactly as it is written, and he knows you are talking nonsense. He knows that however much he tries to obey you, there are still countless points he must decide for himself.

-- R.G. Collingwood The Principles of Art

R.G. Collingwood