To answer your question, we have to pose a few others: Is this a supernatural story or one of psychological horror, or both? Is Roderick Usher the only mentally ill character in the story? And how mentally sound is the story’s unnamed narrator himself?
To start with, it would have been easier to diagnose Roderick’s disorder if Edgar Allan Poe’s tale dealt purely with psychological horror. We could have assumed that Usher is either paranoid or schizophrenic, since he hears voices and imagines his house is a living, malignant entity. However, the very fact that the narrator also experiences uncanny, paranormal phenomena, such as a horrifying aura about the house of Usher that fills him with an “utter depression of the soul,” indicates that things are not just happening inside Roderick’s head. However, Roderick is in a state of extreme, nervous agitation, which has transformed his very appearance.
The now ghastly pallor of the skin, and the now miraculous lustre of the eve, above all...
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