Many of Poe's short stories are effective in their portrayal of terror and madness precisely because the narrators of these stories cannot be trusted to tell the truth. For instance, the narrators of "The Tell-Tale Heart" and "The Black Cat" insist upon their sanity as a preface before providing a chilling interpretation of the criminal mind, while the protagonist's opium addiction in "Ligeia" casts doubts upon the extent of the supernatural in his experiences after the death of his first wife Ligeia. In all cases, Poe employs the first-person point of view in order to prevent knowledge of other potential points of view. Similarly, although Poe's poetic works are less focused on murder than many of his short stories, questions about the supernatural and about reality continue to pervade our understanding of Poe's poems, many of which are also told in the first person.
In Poe's works, a standard sign of the narrator's possible lack of sanity is his inability to question his own bizarre behavior. One of the clearest examples of this disconnect between the rational mind and the obsessed mind appears in the poem "Annabel Lee," where the narrator displays signs of paranoia in his suspicions of a conspiracy between Annabel Lee's highborn kinsmen, the jealous angels in Heaven, and nature itself in causing her death. Furthermore, he concludes the poem in a peaceful and optimistic tone as he explains calmly that he sleeps every night beside her tomb on the seashore. This detail reveals the extent of his fixation upon her memory and causes us to suspect that his largely sweet and innocent account of pure love actually hides a highly unbalanced mind.
In addition to omitting local explanations for abnormal behavior, Poe's unreliable narrators often try to explain strange occurrences in a rational manner before losing control over their thoughts and succumbing to the significance of the supernatural. Just as the narrator of "The Black Cat" at first tries to find a scientific cause for a number of sinister coincidences but later begins to believe that the cat's soul has returned to haunt him, the narrator of "The Raven" initially laughs at the raven, thinking its appearance to be an odd coincidence. However, after he imagines that he hears the footfall of angels, his mood shifts instantly and he loses his temper in his agony at memories of the lost Lenore. The sudden nature of his mood swing and his subsequent detachment from reality characterizes him as a man driven insane by grief.
Although not all of Poe's protagonists in his poems show clear signs of madness, many do show elements of instability or of hallucinations. The narrator of "Ulalume" speaks with his soul and imagines it to be a separate, female entity named Psyche, while the knight of "Eldorado" encounters a "pilgrim shadow" and curiously asks the shade for directions to a mythical city. Even those who seem to be self-aware, such as Tamerlane in the eponymous poem, often display self-serving biases -- although Tamerlane's egotistical absorption is hardly as severe as the faults of others and may merely be the result of Poe's use of the first person. Nevertheless, Poe's style of narration often leaves the matter of the protagonist's trustworthiness open to interpretation and ultimately allows for a darker understanding of his works.