Metaphor: The Monster in the Wall
The concluding image of the story can be seen to confirm that the black cat is a metaphorical feline even to the narrator: “I had walled the monster up within the tomb!” The black cat of a guilty conscience is revealed here with two metaphors: not only has the cat become fully endowed with symbolic value as a hideous abomination, but also the wall of the narrator's home—a place for safety and living—has become a tomb, a "home" for the dead.
Simile: From Infant to Abomination
The full extent of how deeply the guilty conscience of the narrator has been invested in the cat is exhibited in one of the most effective similes in the story when the animal is heard making “a cry, at first muffled and broken, like the sobbing of a child, and then quickly swelling into one long, loud, and continuous scream, utterly anomalous and inhuman.” The movement of the cat in narrator’s mind from something to be pitied with its muffled yelp to the dreadful shrieking of something unnatural is swift.
Metaphor: Alcoholism
On several instances, the narrator engages metaphor to distance himself from his culpability in consuming an excess of alcohol and the violence he knows will ensue. Alcoholism is described in metaphorical terms as “Fiend Intemperance,” which is a “disease which grew up on me,” ultimately transforming into a “fury of a demon” capable of possessing him. The consequences of his alcoholism contribute to the blackness of his guilty conscience, and his refusal to take responsibility explains his desire to transfer that responsibility to a cat.
Simile: The Cat
The narrator begins to hate the second cat and "came to look upon it with inutterable loathing, and to flee silently from its odious, as from the breath of a pestilence." This simile makes the reader aware of just how much the narrator hates the cat and how much it plagues him. If the cat truly is a stand-in for his conscience, this simile is perhaps even more effective: He thought he was okay to get another cat—metaphorically, his conscience was salved over time—but clearly he is not okay, and this cat is even more terrible to him than the first—metaphorically, his conscience has come back to plague him.
