Every so often I come across a passage that seems to me so elemental in its ideas that I feel obliged to quote it without any edits. The following comes from Stephen Orgel's fascinating introduction to the Oxford Edition of The Tempest (1987), and among its many important points, it should help playgoers (me included) to realize that a performance is more finite in its possibilities than is a text. Or, as Emily Dickinson put it, "A pen has so many inflections, a voice but one." Here's the unabridged excerpt:

"But all interpretations are essentially arbitrary, and Shakespearian texts are by nature open, offering the director or critic only a range of possibilities. It is performances and interpretations that are closed, in the sense that they select from and limit the possibilities the text offers in the interests of creating a coherent reading. In what follows I have undertaken to be faithful to what I see as the characteristic openness of the text that has come down to us, and to the variety and complexity of its contexts and their implications. To do this is to indicate the range of the play's possibilities; but it is also to acknowledge that many of them (as is the nature of possibilities) are mutually contradictory. There is nothing anomalous in this. The text that has come down to us is poetry and drama of the highest order, but it is also, paradoxically, both less and more than literature. It is, in its inception, a play script to be realized in performance, with broad areas of ambiguity allowing, and indeed necessitating, a large degree of interpretation. In its own time its only life was in performance, and one way to think of it is as an anthology of performances before Ralph Crane transcribed it for the printer in 1619 or 1620. As a printed text, it is designed to provide in addition the basis for an infinitude of future performances, real and imagined. For all our intuitions of autobiography, the author in it is characteristically unassertive, and offers little guidance in questions of interpretation or coherence. For Shakespeare and his company, the text was only the beginning, not the end, of the play."