I shall now copy n paste the parts I care to remember :)
The Iceberg Theory (also known as the "theory of omission") is the writing style of American writer Ernest Hemingway.
As a journalist he learned to focus only on events being reported, and to omit superfluous and extraneous matter. When he became a writer of short stories, he learned to write a surface story in which he omitted or hinted at the point of the story. Hemingway believed the true meaning of a piece of writing should not be evident from the surface story because the crux of the story lies below the surface. Critics such as Jackson Benson claim his iceberg theory, or theory of omission, in combination with his distinctive clarity of writing, functioned as a means to distance himself from the characters he created.
After graduating from high school he went to work as a cub reporter ... where he quickly learned that truth often lurks below the surface of a story.He learned about corruption in city politics, and that in hospital emergency rooms and police stations a mask of cynicism was worn "like armour to shield whatever vulnerabilities remained"