In his short story 'The Tell-Tale Heart' (1843), Edgar Allan Poe writes in the main character's narration, 'How, then, am I mad? Harken! and observe how healthily—how calmly I can tell you the whole story... Now this is the point. You fancy me mad. Madmen know nothing. But you should have seen me. You should have seen how wisely I proceeded - with what caution - with what foresight - with what dissimulation I went to work! I was never kinder to the old man than during the whole week before I killed him.' What did Poe want readers to infer from this text?