The theme of a story is a hard to component to examine properly. The problem can be when the reader places his/her own interpretations on the story through the lens of his/her experiences, background and stereotypes.
A person’s experiences shape his/her perceptions. The writer knows very little about the potential readers other than the target market. The writer can have one intended theme to the story only to have it coopted, misunderstood or ignored by the reader. A perfect example is the Lord of The Rings books by J.R.R. Tolkien. The author never said the story was an allegory for World War II, nor did he ever claim it to be a commentary on race, class or any other issue. Yet to read the interpretation of his work it was inspired by the events of both World War I and the failure of the West to take action against the rise of Hitler before World War II. What if his only purpose was entertainment? The author may have simply wanted a new appreciation of nature. Look at the story elements: talking trees, people who live in trees and love the woods, characters with powers over nature.
The background a person brings as a reader causes them to superimpose their viewpoint on the writer’s work. A man with a background full of persecution and subordinate relationships would see the story of Walter Mitty very differently than a woman with an Alpha personality and dominant relationships. They both would view the theme differently. The author may have intended satirical humor. The readers may interpret it as a depressing tale in the case of the man and a how to guide in the case of the woman.
The stereotypes that are a part of everyone’s viewpoint (unintended of course) can have a major influence on how the reader views the tale. A reader who has experienced most period pieces as boring and un-relatable would approach Johnny Tremain, with a very different