Against Interpretation

In reading Susan Sontag's Against Interpretation and Other Essays I came across this passage on interpretation.

Interpretation is a radical strategy for conserving an old text, which is thought too precious to repudiate, by revamping it. The interpreter, without actually erasing or rewriting the text, is altering it. But he can't admit do to doing this. He claims to be only making it intelligible, by disclosing its true meaning. However far the interpreters alter the text, they must claim to be reading off a sense that is already there.