One of the driving forces in this opening and throughout the story is not the narrator's insistence upon his "innocence" but on his "sanity". His drive to convince, however, is self-destructive because he fully admits he is guilty of murder. His denial of insanity is based on his systemic actions and precision - a rational explanation for irrational behavior (murder). This rationality, however, is undermined by his lack of motivation ("Object there was none. Passion there was none."). Despite this, however, he says the idea of murder, "haunted me day and night." The story's final scene, however, is a result of the narrator's feelings of guilt. Like many characters in the Gothic tradition, his nerves dictate his true nature. Despite his best efforts at defending himself, the narrator's "over acuteness of the senses," which help him hear the heart beating in the floorboards, is what convinces the reader that he is truly mad. Readers during Poe's time would have been especially interested amidst the controversy over the insanity defense in the 1840s.