[E]quating a poem with its text may arouse some protest, on the ground that the more immediate or intrinsic properties of classes of inscriptions and utterances hardly coincide with the aesthetically important properties of the poem. But in the first place, defining literary works no more calls for setting forth all their significant aesthetic properties than defining metals calls for setting forth all their significant chemical properties. In the second place, immediacy is a suspect notion and aesthetic relevance a subtle one; and no end of confusion has arisen from association of the two. To identify the literary work with a script is not to isolate and dessicate [sic] it but to recognize it as a denotative and expressive symbol that reaches beyond itself along all sorts of short and long referential paths.
Nelson Goodman, Languages of Art: An Approach to a Theory of Symbols