The central or dominant idea behind the story; the most important aspect that emerges from how the book treats its subject. Sometimes theme is easy to see, but, at other times, it may be more difficult. Theme is usually expressed indirectly, as an element the reader must figure out. It is a universal statement about humanity, rather than a simple statement dealing with plot or characters in the story. Themes are generally hinted at through different methods; a phrase or quotation that introduces the novel, a recurring element in the book, or an observation made that is reinforced through plot, dialogue, or characters. It must be emphasized that not all works of literature have themes in them.