In order to answer the question of whether or not Montresor, the narrator of "The Cask of Amontillado ," is unreliable, think through the narrator's characteristics. Is he suffering from a mental illness? Does he display delusional behavior? Is he inherently evil? Since you need to defend your answer...
In order to answer the question of whether or not Montresor, the narrator of "The Cask of Amontillado," is unreliable, think through the narrator's characteristics. Is he suffering from a mental illness? Does he display delusional behavior? Is he inherently evil? Since you need to defend your answer with textual evidence, consider the following events from the story.
Montresor has vowed to get revenge on Fortunato, though we don't know exactly what Fortunato has done. We do know that Montresor's family motto is "Nemo me impune lacessit," which means "no one punishes with impunity" or, in other words, no one insults my family and gets away with it. The family motto was meant to be similar to a mission statement. It generalized the family's beliefs and values. Readers can then infer that Montresor's family was guided by the "an eye for an eye" philosophy, but the fact that he wants revenge in and of itself does not make him unreliable.
We don't know what Fortunato has done, but we do know this from the text: "The thousand injuries of Fortunato I had borne the best I could, but when he ventured upon insult, I vowed revenge." We can infer that this was a verbal insult, and we see later in the text that Fortunato insults Montresor again by making the gesticulation of the freemason sign and then mocking Montresor for not knowing the secret symbolism. Given this, do you think it is reasonable to kill a person for mocking another person?
Consider the method that Montresor uses to kill Fortunato. It's very much akin to a cat playing with its prey before taking its life. He lures Fortunato to the catacombs with the promise of a cask of rare wine, knowing that Fortunato is a connoisseur of wine and will not be able to resist this offer. Next, he taunts him with turning back, pretending to be concerned about his health, all the while giving him more wine to further his already drunken state. Montresor knows that Fortunato will not agree to go back, because he is obsessed with the idea of the amontillado. Lastly, he chains up a completely incapacitated man and bricks in an alcove in order to bury him alive. When Fortunato comes to his senses and realizes what is happening, he begs for his life. Montresor responds by mocking him and matching his screams, increasing Fortunato's terror in the face of his impending doom. This is not a crime of passion. This is calculated and perverse. Does this qualify as a narrator who is truly evil with no sense of right and wrong? If you think so, you may judge him as an unreliable narrator.