“The Secret Life of Walter Mitty” can be compared to the story of “The Tell-Tale Heart” by Edgar Allan Poe. While the two stories were written at different times and in differing styles, they both emphasise the sanity or lack thereof of the main characters.
For example, in Poe’s story, the narrator is driven insane by the beating of the older man’s heart, even after his death. There is no way the narrator could be continuing to hear the heartbeat after death unless he lacked sanity when he committed the act. Walter Mitty, by comparison, loses himself in various exciting scenarios to probably escape the mundane things he has to do in his day to day life. Out of the four other stories discussed, there are no other main or supporting characters that exhibit such signs of insanity.
Walter Mitty, as compared to the narrator of Poe’s story, is a bit less insane. This is because he does not go out and murder someone that is the object of his fixation. In order to get through his daily life, he has to imagine these things and perhaps wishes that he were more famous or notable than he actually is. Each fantasy is of someone with power or fame. The narrator in Poe’s story appears to be obsessed with this one imperfection in the older man and therefore decides that he needs to kill him to be rid of that imperfection.
Another difference between the two stories is the style. Poe’s story is done in the first person from the perspective of the narrator. Thurber’s story is done from a third-person perspective, as if we are looking into the life of Walter Mitty, including during the fantasy type scenarios. There is always someone or something in Thurber’s story that brings Mitty back to reality after his fantasies. In Poe’s story, there lack such things that can bring the narrator back to reality. In fact, Poe’s narrator appears to delve deeper and deeper into insanity. Both stories are stylised to emphasise the mental state of the main characters.