Ernest Hemingway was famous for using understatement in his fiction and for being a great advocate of this technique. He once said that a good work of fiction should resemble an iceberg, in which the greatest part of the meaning of the story lies beneath the surface. In other words, Hemingway's fiction often implies meanings rather the openly stating them. Hemingway expects his readers to be able to draw inferences from the details he provides.
A good (and brief) example of this technique can be found in his famous short story "Hills Like White Elephants." In this story, two people -- a man and a woman -- sit in a Spanish railway station waiting for a train. They engage in a discussion in which the chief subject of conversation and disagreement (should the woman have an abortion?) is never made explicitly clear. In fact, the word "abortion" is never mentioned. In order to discover what the subject of discussion is, we have to listen to clues. Neither Hemingway nor the characters will come right out and tell us, as might have been the case is a story by another author.
In this story, we cannot even be sure of the specific identities of the two characters. The man is referred to as "The American," and it is he who calls the young woman with whom he is talking "Jig." Hemingway never explicitly tells us who they are, what their personalities are like, what their backgrounds are, what their values are, or even what they decide to do in the end. We have to figure out all these details for ourselves.
Of course, Hemingway does provide us with many clues, so that in reading the story we in a sense behave as detectives. By the end of the story, most readers have figured out that the subject of their tense discussion is abortion and that the man wants the woman to have an abortion while she feels real reluctance.
One nice example of Hemingway's use of understatement and implication in this story occurs when the young woman looks off at a line of distant hills and comments on them:
"They look like white elephants," she said.
"Ive never seen one," the man drank his beer.
"No, you wouldn't have."
Notice how few words Hemingway uses. He does not even write "the man said as he drank his beer," nor does he explicitly identify the speaker of the last quoted sentence (although these words are obviously spoken by the woman).
The woman's initial comment suggests that she is highly imaginative. She can look at hills and see their resemblances to elephants. However, Hemingway never comes out and tells us this. He does not end the sentence by writing, "she said imaginatively, in a somewhat romantic tone." He leaves us to infer these conclusions for ourselves.
And what does the final sentence mean? Is the woman implying that the man is unimaginative? Is she implying her disappointment in him and in their relationship? Are her words tinged with anger? Again, Hemingway doesn't explicitly tell us. Instead, he uses understatement so that we must decide for ourselves what this statement -- and indeed the whole story -- means.