These set the model for flash fiction – fiction that is condensed without unnecessary descriptive detail. In "A Moveable Feast" Hemingway wrote that "Out of Season", written in 1924, was the first story where he applied the theory of omission, known as his Iceberg Theory. He explained that the stories in which he left out the most important parts, such as not writing about the war in "Big Two-Hearted River", are the best of his early fiction. As Carlos Baker describes the technique, the hard facts float above water while the supporting structure, including the symbolism, operates out of sight. Hemingway wrote in the preface to "Death in the Afternoon", a writer may choose what to include and what to omit from a story.