Montresor states that the motive for his crime is revenge. In his mind, he is the long-suffering innocent party who has suffered "the thousand injuries" of Fortunato with forbearance, but when "insult" follows, can endure Fortunato no longer. For Montresor, revenge is not a simple matter, but must be carefully executed: to succeed he has to get away with his crime without being caught, and his victim must know that Montresor is the agent of his doom.
Poe writes in the Gothic genre, characterized by gloomy, un-homelike (unheimlich) settings, psychological terror, and such uncanny features as death and doubling. This leads us to wonder if Montresor might subconsciously perceive Fortunato as his double or twin (doppleganger), a reading supported when Montresor explains that "in the matter of old wines he was sincere. In this respect I did not differ from him materially; —I was skilful in the Italian vintages myself, and bought largely whenever I could." If this is the case, is Montresor's real motive an attempt to "bury" parts of himself he abhors and can't face by killing his double? Is "revenge" simply a rationalization?