Common among many of Ernest Hemingway's novels is the concept popularly known as the "Hemingway hero," an ideal character readily accepted by American readers as a "man's man". In The Sun Also Rises, four different men are contrasted and compared in the world of the 1920s as they engage in some form of relationship with Lady Brett Ashley, a near-nymphomaniac Englishwoman who indulges in her passion for sex and control. Brett plans to marry her fiancé for superficial reasons, completely ruins one man emotionally and spiritually, separates from another to preserve the idea of their short-lived affair and to avoid self- destruction, and denies and disgraces the only man whom she loves dearly. All her relationships occur in a period of months, as Brett either accepts or rejects certain values or traits of each man (she usually rejects him completely, though, after she's through with him). Brett, as a dynamic and self-controlled woman, and her four love interests help demonstrate Hemingway's standard definition of a man and/or masculinity. Each man Brett has a relationship within the novel possesses distinct qualities that enable Hemingway to explore what it is to truly be a man. .
The Hemingway man thus presented is a man of action, of self- discipline and self-reliance, and of strength and courage to confront all weaknesses, fears, failures, and even death. Jake Barnes, as the narrator and supposed hero of the novel, fell in love with Brett some years ago and is still powerfully and uncontrollably in love with her. However, Jake is unfortunately a casualty of the war, having been emasculated in an accident. Still adjusting to his impotence at the beginning of the novel, Jake has lost all power and desire to have sex. Because of this, Jake and Brett cannot be lovers and all attempts at a relationship that is sexually fulfilling are simply futile. Brett is a passionate, lustful woman who is driven by the most intimate and loving act two may share, something that Jake just cannot provide her with.