I consider exposing the librarian's message as a bluff. The initial impulse upon awakening is to call upon repression and view the dream as meaningless, "phoney." A symbol can be seen as a bluff, a deception, a substitute, a threat to reveal some threatening underlying meaning.
But I don't carry out my threat of exposing the librarian's bluff. Since all thought is symbolic, you can't "expose" a symbol; you can only exchange one symbol for another. Who's to say what the true meaning of a dream symbol is? Perhaps the dream thoughts serve their purpose just as well in the form in which they are dreamed. Meaning is in the mind of the beholder.