The theme in literature is the major lesson or idea that is proven by the story. It is typically implied rather than explicitly stated, except in some fables that end with a direct statement of theme. The theme helps tie the events of the story together in a meaningful way.
To find theme, the reader should ask himself what he learned about human nature or life in reading the story. It can be found by examining which behaviors were rewarded with positive outcomes or punished with negative consequences. The reader can also determine theme by analyzing literary devices such as tone, diction or imagery, or by looking at which traits or qualities were ascribed to the good and bad characters. This helps the reader see which qualities are being advocated by the author.