From the very first sentence, "The Tell-Tale Heart," the reader is taken into the mind of a very disturbed person. Not to stray from the instructions of this assignment, I will discuss the two most important aspects of the short story. Madness (insanity) and paranoia are the two factors that "make" the main character in the story.
Our subject in the story is extremely troubled. We know nothing of his past, nor do we know anything of the old man except that he is rich and has that hideous eye. The root of this madness is unknown as well, which I believe was all done on purpose by the author. The man admits to his insanity, as a disease. Rather, he calls it a sharpening of the senses. Just this opening paragraph makes the reader see that his insanity is essential in getting the story across. The reader would not get a good feel for the story if it was not for this insane first person narration. The main topic that his insanity brings up is his denial of his insanity.
He said that he loved the old man. He had no problems with him nor did he wish any harm done upon him. Why then would he want to kill him? Surely it could not be because of that eye. But there was no other motive. He cannot bring himself to admit to the point that only a mad man would kill someone just because of the way their eyes looked. The fact that his senses were heightened had nothing to do with his hate for the eye. The heightening of the senses, I believe, was brought on by the loss of his ability to distinguish the difference between right and wrong, of morality and immorality.