What effect does Edgar Allan Poe achieve in "Tel-Tale Heart"?

Edgar Allan Poe achieves the destruction of a constant reminder of mortality. He use “eye” to symbolize “I”. Poe presents the dark side of people in the story. The narrator says he or she is not mad, and tries to convince people that fact by how carefully this brutal crime was planned and executed. However, I still think the narrator is insane. In the story, the eye of the old man makes the narrator feels fear. The narrator becomes a victim to the madness which he had hoped to elude. And this irrational fear leads to murder. The narrator really means he or she wants to destroy the evil “I” when he or she says he or she must destroy the evil “eye”. The narrator is insanity’s darkness. He or she is in a claustrophobic state. The narrator is a scheming murderer. He or she hides in the darkness, and does everything at night. He has observed couple nights before his murderous behavior. He exhibits a pride when he is closer and closer to his target, the old man’s eye, and