Edgar Allan Poe's "The Tell-Tale Heart" is rife with the exaggeration of the insane, and it should be: The narrator, a genuine madman, takes hyperbole as reality. "I heard all things in the heaven and in the earth," he says, and he uses this cosmic overstatement as proof of sanity. Poe's use of hyperbole allows us to perceive the man's delusional state. This lunatic is a literary master's favorite, the unreliable narrator.
Time and Heartbeats
Many of the narrator's hyperbolic observations center on time and sound. "A watch's minute hand moves more quickly than did mine ... for a whole hour, I did not move a muscle," he states as he watches over an old man he ultimately murders. When he imagines the old man's heartbeat, he agonizes, "the sound would be heard by a neighbor!"
Hyperbole Shows Obsession
Poe, according to New York University's literary database, uses "frenetic diction" to underscore the lunatic's obsessive perceptions. This hyperbole-soaked mentality is nowhere more evident than in the story's finale, when the madman "foamed, I raved, I swore" during a quiet conversation with police, as an ear-splitting imaginary heartbeat leads him to distraction and finally confession of his murderous deed.