The main conflict in this story is between the narrator's two chief desires: to get away with killing the old man whose vulture-like blue eye seems to him an evil eye and to still the old man's beating heart, which he thinks he can hear, and, on the other hand, to be punished for his crime. His desire to be rid of the old man is overwhelming, so he kills him, fulfilling that desire. When the police come, our narrator is calm and civil, and it is clear they don't suspect him. Then his guilty conscience comes into play. He imagines he hears the heart of his victim beating beneath the floorboards of the room where he sits with the police. Though the sound appears to be only in his imagination, as the police hear nothing, the man's guilt overwhelms him:
It grew louder --louder --louder! And still the men chatted pleasantly, and smiled. Was it possible they heard not? Almighty God! --no, no! They heard! --they suspected! --they knew! --they were making a mockery of my horror!-this I thought, and this I think. But anything was better than this agony! Anything was more tolerable than this derision!
The narrator relieves his internal conflict through confessing. Poe shows how a person can be driven not by forces outside himself, but by internal demons.
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