How Does One Classify Horror Literature?

As friends of literature, I am sure you all are aware of what books are deemed worthy to place under the "horror" genre--for example, "Frankenstein," by Mary Shelley and "Dracula" by Bram Stoker. Although these are the most obvious, how about the ones we consider to be horror that are less obvious? First, take a glimpse back to Oscar Wilde's intriguing classic, "The Picture of Dorian Gray."

Naturally, one's reaction would to immediately pinpoint the certain aspects that make this classic a stereotypical "horror": The murder, the insanity, and, most importantly, the ghastly portrait of Dorian's soul. Other than these significant features, how else does this book follow the rules of what constructs a horror novel? From my perspective, I see nothing else that would convince me that this piece could be considered a "horror" classic. Sure, the idea may evoke fear in the audience, but not as significantly as one that contains "otherworldly" beings---such as these ghostly authors: H.P Lovecraft, Stephen King. The better classification as I visualize, would be under, respectively, "Mystery" or "Thriller" instead.

In addition to Wilde's classic, I suggest that "Phantom of the Opera," by Gaston Leroux is not a horror piece, either. Why? Does the idea of a disfigured, misunderstood man living under the opera house spook you? Perhaps to some, but this classic deserves recognition as a romance--the courage of the phantom taking advantage of the one and only chance at finding a partner that would adore him for his personality.

Perhaps I am gazing too deeply down the rabbit hole. But, as far as what my perspective insists, these pieces of literature should not be considered a part of the horror genre. Naturally, there are probably other novels that deserved to be "re-knighted" with another classification. Please feel free to share any thoughts on my blurb!

~Lovely Iris.