The opening paragraphs of the "The Black Cat" by Edgar Allan Poe reveal valuable information about the narrator, his animals, and his relationship with his animals just by the language the narrator uses. For example, he tells us he is going to die tomorrow for something that he has done, something he describes as "nothing more than an ordinary succession of very natural causes and effects." From these words we understand both that he is unreliable and that we should pay attention to his words.
So, when he describes his beloved black cat, Pluto, we should pay close attention to his words--especially given the title of the story.
This [cat] was a remarkably large and beautiful animal, entirely black, and sagacious to an astonishing degree. In speaking of his intelligence, my wife, who at heart was not a little tinctured with superstition, made frequent allusion to the ancient popular notion, which regarded all black cats as witches in disguise. Not that she was ever serious upon this point--and I mention the matter at all for no better reason than that it happens, just now, to be remembered.
It is no accident that the narrator describes Pluto as sagacious (being wise and having good judgment) and intelligent.
Pluto's ability to both outsmart his owner as well as recognize him for what he is--a cruel, capricious, and selfish man--is demonstrated throughout the story. When the man's character begins to change because of the "Fiend Intemperance" (alcoholism), Pluto, who once followed the man everywhere he went, now stays away from him after he has been drinking. That is, of course, a wise decision; however, one night the animal does not move away quickly enough and the man grabs him and, in a rage, cuts one of Pluto's eyes out of its socket.
From then on, the sagacious cat runs away "in extreme terror" whenever the man comes near him, another wise move on the cat's part. While the man at first understands the cat's reticence to be near him, soon the man gets infuriated again at Pluto for not being as friendly and accommodating to him as he was before the cutting. Smart cat.
But then Pluto, who has been an excellent judge of character so far regarding the man, makes a fatal mistake because the man tricks him. The cat has learned to avoid the man when he is in a rage, but one day when the man does not seem enraged at Pluto he manages to do a terrible thing.
One morning, in cool blood, I slipped a noose about its neck and hung it to the limb of a tree;--hung it with the tears streaming from my eyes, and with the bitterest remorse at my heart;--hung it because I knew that it had loved me, and because I felt it had given me no reason of offence;--hung it because I knew that in so doing I was committing a sin--a deadly sin that would so jeopardize my immortal soul as to place it--if such a thing were possible--even beyond the reach of the infinite mercy of the Most Merciful and Most Terrible God.
Once the man started drinking, Pluto knew he was capable of awful things. Unfortunately, he was unable to avoid the effects of the the man's alcohol-driven cruelty forever, and he is killed. Perhaps there was something to the man's wife's early assertion that black cats are connected to witchcraft, as well, because that is not the end of Pluto. The eerie image of the hanged, one-eyed cat appears over and over in the man's life. In fact, it is indirectly responsible for the man's demise, making Pluto a most wise and discerning (sagacious) creature.