Before Christianity, paganism supplied humanity’s monsters. Initially, many were hybrids of wild animals and humans, among which were the centaur, the harpy, the lamia, the mermaid, the minotaur, the satyr, and the Sphinx. Most of them represented natural forces.“We have seen the enemy, and he is us.” -- Pogo
Christianity contributed the devil and his legions of lesser evil spirits, the demons.
Now that Christianity and other worldwide religions are in eclipse--in agricultural and progressive nations, at least--writers of horror fiction have had to find their monsters elsewhere.
Science has been a major source of modern horror fiction’s nightmarish creatures. Other worlds have supplied writers with menacing demons, extraterrestrial diseases, and a variety of paranormal threats including clairvoyants, telekinetic travelers, time travelers, homicidal cyborgs, and rampaging robots.
Psychology has also been a source for many of the inner demons that haunt the world of the self. Sigmund Freud contends that modern monsters are aspects of ourselves which we have, as it were, cut off and cast out. They are embodiments, in other words, of those elements of ourselves that we repress.
As a species, we have gone from the Other as a duality of the bestial and the human to the Other as a supernatural seducer, tempter, and deceiver to the Other as the rejected elements of a would-be self--from natural to supernatural to psychological. In the process, the monster has gone from the general to the specific.
Edgar Allan Poe showed us the way, substituting the madman for the demon, ghost, vampire, werewolf, or other paranormal or supernatural threat. However, there is another source for the modern monster: the Self--or, rather--the wannabe Self which we repress. At first, such a source might seem too finite for the task we have set it, which is nothing less than that of being the maker of all things destructive, menacing, destructive, evil, and lethal. We need not worry, however, about whether our supply of monsters will peter out. There are as many inner demons as there are individual men, women, and children.
Just the list of inner demons which have found expression as objective Others in the work of Stephen King suggests the breadth of the range of possibilities for such embodiments of iniquity. His novels have depicted demons of child abuse and religious fanaticism (Carrie), narcissistic self-indulgence and hypocrisy (Needful Things), alcoholism and psychosis (The Shining), spousal abuse (Rose Madder), adultery (Cujo), government abuse of its citizenry (Firestarter), and a host of other Others.
To develop the modern monster, one must become adept at seeing the repressed Other in oneself and in other people, for, today, the repressed is the monstrous.
Two clues are rationalization and hypocrisy. We want to be perfect, even though we know that we are not, and cannot be, without fault. Therefore, we tend to deny what is obviously true to others about behaviors which we may do but certainly not want to admit that we do them.
Instead, we lie to ourselves about our behavior, make excuses for our conduct, and deny that we have acted in anything but an admirable and proper manner. What we would condemn in others, we accept, or even celebrate, in ourselves. By identifying behaviors which we rationalize or would condemn in others but approve in ourselves, we can identify the inner demons both of ourselves and others.