Theme is the central idea, question or concern a story keeps returning to, which gives meaning to its events beyond the plot itself.
Where the term comes from
Merriam-Webster gives the first sense of theme as a subject or topic of discourse or of artistic representation, with the example of an album that focuses on themes of love and loss. It also lists a specific and distinctive quality or concern, and, in music, a melodic phrase that forms the subject of a composition. The word is general. In fiction, the idea is the thing a book is about under the plot, such as grief, loyalty or the cost of ambition.
An example
In a novel about two sisters running a failing bakery, the plot is about money, an inheritance and a rival shop. The theme is what loyalty costs. We see it when one sister keeps a secret to protect the other, when a customer pays with a favor rather than coins, and when the final loaf is given away. No character announces the theme. It shows in what each person chooses to give up, and in how the ending answers the question without lecturing.
Common mistakes
- Choosing a message first and bending the story to it, so the characters turn into mouthpieces.
- Stating the theme aloud in dialogue or narration, which removes the reader's chance to find it.
- Confusing theme with topic. War is a topic. What war does to a promise is a theme.
- Making the book answer the question too neatly. Some of the best themes stay open.
- Letting scenes pull in different directions with no recurring concern.
How to check your manuscript
Read the book's first scene, its midpoint and its last scene, and write one sentence on what each says about people. If the sentences rhyme, you probably have a theme, even if you never planned one. Then ask where the characters disagree about it, since a good theme appears as argument, in the choices of different people. Check the ending: does it take a side, or at least show the cost of each? Early drafts often discover their theme late, so this is a revision job. The revision guide describes passes you can use, and the entry on character arc shows how inner change carries meaning.