He also admits that, "The disease had sharpened my senses- (1471). This leads the reader to believe that he is speaking of his insanity. The reason for his actions was one of the old man's eye, which he described it to be a "pale blue eye, with a film over it" (1471). This is easily recognizable to the reader as an eye with a cataract. For a sane person this would be nothing to obsess over, yet the eye supposedly haunted the narrator day and night. Any sane person would take a physical defect as another aspect of life and deal with it. One statement by the narrator sums up his mental state: "You fancy me mad. Madmen know nothing. But you should have seen me" (1471). In this statement the narrator is trying to deny his insanity by saying that madmen are clumsy in their actions, and that he is fully aware of what he is doing. This statement is as close to a self-admission of insanity as one will ever hear. .
The mental setting is put into place by the narrator's own statements. This setting is pure chaos starting in the head of the killer and spilling out into the physical world around him resulting in an unnecessary death. When the narrator is explaining the end of his tale to the reader, he states the beating of the heart was unbearable on his conscious:.
"I paced the floor to and fro with heavy strides, as if excited by the observations of the men-but the noise steadily increased I foamed-I raved-I swore! the noise arose over all and continually increased. It grew louder-louder-louder! They heard!-they suspected!-they knew! I felt I must scream or die!"(1474). The narrator proceeded to admit his killing of the old man. Obviously, his mental state was one of pure fear and disillusion. An auditory hallucination of a dead heart beating caused so much mental anguish in the narrator that it made him confess to the crime. This indeed shows insanity. Yet this insanity was not as strong as the guilt pushing through it.