A work of art that contains theories is like an object on which the price tag has been left.

The line appears in Proust’s final volume of In Search of Lost Time, where he criticizes the impulse to make literature overtly “intellectual” by inserting explicit theories and logical argumentation into an artistic work.

Proust is saying that when a work of art advertises its ideas too directly, it becomes less aesthetically persuasive—like a product still showing its price—because the reader is pushed to notice the explanatory machinery instead of experiencing the art itself.

A book in which there are theories is like an article from which the price mark has not been removed.

A work in which there are theories is like an object upon which the price is marked.

A work of art that contains theories is like an object on which the price tag has been left.

A work in which there are theories is like an object which still has the ticket that shows its price.