Kipling famously wrote that "there are nine and sixty ways of constructing tribal lays, / And every single one of them is right." There are surely just as many ways to classify horrific and Gothic fiction. One simple approach is to look at the genre in terms of our three great fears.
The first and very old fear is that simple dread of the horrors out there in the darkness, the woods or the cellar – the external Thing that we know with childish certainty is Coming To Get Us. Grendel the man-eating monster of Beowulf is an early example, carrying men off from the firelit feasting-hall of Heorot for twelve grim years before a hero intervenes. Many, many ghost stories play on such fear, as does Bram Stoker's classic vampire melodrama Dracula (1897).
Count Dracula is a fine symbol of invasive evil from outside. In the course of Stoker's novel he invades England, then our homes, and finally our bodies. The darkness is always trying to come indoors, sometimes by main force, sometimes by trickery as in most stories of bargains with the Devil. Susan Cooper's children's fantasy The Dark is Rising repeatedly shows its bad guys, the Dark, as ruthless invaders – consciously echoing the author's childhood dread of German invasion as she grew up during World War II. In one telling scene, an agent of the Dark easily gains entry to the boy hero's home because unknowing adults find it socially impossible not to ask him in.
Often in Gothic fictions the circle of light is very small indeed, and the dark presses close all around us. Often there's a sense of being trapped inside what the Encyclopedia of Fantasy (ed. John Clute and John Grant, 1997) calls an Edifice, a building or construction that's not just brick and stone but contains labyrinths, paradoxes, solidified metaphors, or architectural wrongness that can extend into metaphysics. The grandaddy of all these sinister places is the haunted castle of Hugh Walpole's The Castle of Otranto (1765), whose eerie corridors were soon echoed in other Gothic fantasias like Ann Radcliffe's The Mysteries of Udolpho (1794). In the twentieth century, the best known example of this grotesque architectural tradition is Mervyn Peake's less immediately sinister but still pervasively oppressive edifice Gormenghast – see Titus Groan (1946) and Gormenghast (1950).
The ultimate bad place, of course, is Hell, though fictional visits there are relatively rare. Dante famously and definitively mapped the circles of Hell in the Inferno segment of The Divine Comedy (written 1300-21), not omitting to show the awful tortures awaiting his own political enemies. The evil Caliph in William Beckford's Arabian tour-de-force Vathek (1786) follows a career of atrocities which culminate with a trip to Hell, where he expects to inherit this vast and wealthy kingdom. Instead, with Eblis's (Satan's) doom-laden words "ALL IS ACCOMPLISHED!", the trap closes and eternal torment begins. (A similar but even more debauched life-style is pursued by the antihero of Matthew Gregory Lewis's sensational 1796 melodrama The Monk, who's undoubtedly bound for Hell but is last seen personally killed by Lucifer, who hurls him down from a great height.) C.S. Lewis offered a subtler, flame-free Hell in The Great Divorce (1946): an infinity of dreary suburbs whose hopeless inhabitants have chosen this tedium rather than face God.
A second fear is rather newer: the terror of what we ourselves may create and unleash. As chastened scientists tended to say in the taglines of uncounted B-movie horror epics, there are things with which man was not meant to meddle. Here the classic archetype is Frankenstein (1818) by Mary Shelley, in which man creates monster and lives to regret it. How very unnerving that the bright tools of scientific reason should twist in our hands and beget monstrosities.
Another celebrated tale of scientific hubris is The Island of Dr Moreau (1896) by H.G. Wells, in which Moreau's attempts to uplift animals to human stature and intelligence produce only twisted, parodic creatures who inexorably revert to beasthood. It's a premise of C.S. Lewis's 1945 That Hideous Strength that (with the token exception of one virtuous chemist) all science leads straight to the Devil. This book's imaginary scientific institute the N.I.C.E. is the most hateful in all fiction, and many of us wondered that the present British government's spin-doctors allowed the setting up in August 1999 of a National Institute for Clinical Excellence.
Thirdly, there's the perennial fear of what horrors may lurk within our own selves. Robert Louis Stevenson dramatized this brilliantly in Strange Case of Dr Jekyll and Mr Hyde (1886), as the good Dr Jekyll's potion opens a forbidden internal door to release his vital but bestial alter-ego Hyde. In the famous line from Walt Kelly's Pogo comic strip: "We have met the enemy and he is us!"
A more conventional interior unpleasantness is madness, which repeatedly features in the nightmare stories of Edgar Allan Poe – to great symbolic effect in "The Fall of the House of Usher" (1839), where the house's cracked facade echoes poor Roderick Usher's cracking mind. Poe's doomed heroes are generally haunted by inner demons and live in an atmosphere of unfocused dread that's suspiciously reminiscent of a bad hangover ... reminding us that Poe had a terrible head for alcohol. Heavy drinkers may well wake up feeling like something from another planet, or like the giant beetle or cockroach into which the hero of Franz Kafka's gloomy "Metamorphosis" (1915) finds himself transformed.
Part of the fun of defining categories is to see how they mix and blur fruitfully together. Ghost stories, the oldest tradition of all, mingle inner and outer fears because one aspect of the lingering chill is that ghosts – from the blood-hungry shades of Virgil's Aeneid and Homer's Odyssey, through Shakespeare's sonorous evocation of Hamlet's shadowy father reporting the pains of hell, to the innumerable revenants of 19th- and 20th-century supernatural fiction – all of these are what we may become. The living dead speak to us in the words of the old epitaph:
As you are, so once was I.
As I am, so shall you be.
Prepare for death, and follow me.
Happily there are jollier spirits. Charles Dickens's Ghosts of Christmas Past, Present and Yet To Come in A Christmas Carol (1843) may cause some brief alarm but are there to reform the horrid miser Scrooge and bring about general rejoicing. Scrooge is duly confronted with the second face of fear, of what he has made – his own twisted life and miserable future – and gets the chance to put it right.
Again, the third fear of what lies within us adds an extra tang to superfically external threats – the dark thrill of complicity. Dracula has powerful undercurrents of sexuality, as, for example, the Count's female victim Lucy changes through the taint of vampirism from a quiet Victorian miss to an aroused woman eager to bestow deadly kisses. The monster of Frankenstein, far from being wholly monstrous, begins his life as a gentle, intelligent being, but is driven to rage and revenge by his creator's and then all humanity's unthinking revulsion at his ugly appearance. "We are all guilty." The downfall of Frankenstein comes not merely from unholy medical dabblings but from this brutal lack of compassion for the creature he's made. In real life, the badly deformed "Elephant Man" found a sympathetic protector; Frankenstein's unprepossessing creation was less lucky.
Terrible uncertainties arise when inner and outer terrors become hard to distinguish. A seminal novel in this category is James Hogg's Confessions of a Justified Sinner (1824), whose Scots protagonist Robert has – in its worst form – the Calvinist belief that he's one of God's chosen and can in the last analysis do no wrong. Being thus ripe for damnation, he's seduced into worse and worse crimes by a silver-tongued doppelganger who may be the Devil ... or may be only a projection from Robert's own tortured mind. And are the ghosts in Henry James's celebrated "The Turn of the Screw" (1898) real, or simply imagined by the story's governess narrator?
This kind of ambiguity was cleverly modernized by Kingsley Amis in The Green Man (1969), which like several of Saki's and Roald Dahl's ingenious contes cruels combines supernatural horror with social comedy. A characteristically boozy, lecherous and unheroic Amis hero is troubled by visions and manifestations which indicate either the overturning of all his easy scepticism and atheism, or the onset of delirium tremens – and it's hard for him to decide which prospect is more frightening.
Some ensnaring labyrinths and edifices may also be all in the mind. Mephistopheles implies as much in Christopher Marlowe's Dr Faustus (1604) when, standing in Faust's study, he speaks of the boundlessness of his realm: "Why, this is Hell, nor am I out of it." The tales of the Thousand and One Nights (which include many horrors and grotesques) have the notorious framing device of Scheherazade telling nested stories within stories to trap the Sultan in an endless web of narrative curiosity and so defer her impending execution. Jan Potocki's The Manuscript Found in Saragossa (1804) transposes this structure into the world of sleep, with the protagonist trapped in layers of dream and unsure how far he is from true wakefulness – except that going to sleep in carnal bliss tends to lead to a rude awakening between two grisly corpses under a gallows. Robert Irwin paid homage to Potocki's construction in The Arabian Nightmare (1983), whose hero falls asleep in a 15th-century Cairo troubled with fears of the Arabian Nightmare (an infinity of torment experienced in dreams, but always forgotten on waking) and loses himself in strange, Escheresque tangles of story and dream that, perhaps, never end.
Less obviously fantastic are the invisible labyrinths of frustration, bureaucracy, and non-explanation that entangle the protagonists of Kafka's The Trial (1925) and The Castle (1926) – very modern nightmares in which it seems that the innocent victims not only can't win but are somehow complicit in their own failure. Jorge Luis Borges's gigantic edifice in "The Library of Babel" (1941) is an exhaustive and dismayingly futile library which contains all possible books – all possible combinations of letters, spaces and punctuation at book length – and must remain a thought experiment since our physical universe isn't large enough to contain it.
The vertiginous fear of immensities – yet another aspect of terror's first face – likewise plays its part in William Hope Hodgson's very strange The House on the Borderland (1908). The house is built over a vast abyss full of "swine-things", and the doomed occupant's story features a remarkable, chilling vision of deep time, entropy and the end of the universe. Interestingly, in Horror: 100 Best Books (ed. Stephen Jones and Kim Newman, 1988), in which a hundred authors wrote about their favourite horror novels, The House on the Borderland was Terry Pratchett's choice.
H.P. Lovecraft was also impressed by this novel, being himself concerned to evoke "cosmic fear". Despite much over-florid language, he conjured up dizzying gulfs of years in stories like "The Shadow Out of Time" (1936), and originated the "Cthulhu Mythos" of vast, uncaring demigods whose mere presence almost accidentally withers human souls. But our third aspect of horror – complicity and intimacy – can still intrude. Some of these entities have interbred with humanity, and shuddering dread merges disconcertingly with longing in The Shadow Over Innsmouth (1936), where the hero realizes that his heritage means that he's slowly transforming and will one day join the scaly, frog-faced Deep Ones under the sea. The horror lies within not his mind but his genes, reminding us of Lovecraft's open racism.
Another image of cosmic scale – the terror of an impossibly huge face, too big to be human, too big to be seen without screaming – appears in a fine novel not often mentioned in the horror/Gothic context, G.K. Chesterton's The Man Who Was Thursday (1908). Chesterton had a whole philosophy of finding joy in commonplace scenes and objects, and in this metaphysical shocker he did the opposite, showing the terror of infinity in flights of stairs or of chaotic formlessness in woodland light and shadow. Elderly decrepitude, dark glasses or a twisted smile make ordinary men into figures of nightmare. But this author loved happy surprises, and all the bogeymen turn into comrades for the hero, except the last and worst, who seemed devilish but may be a mask for God.
The list could be extended indefinitely. Despite repeated scares about their influence on bookish children who might want to grow up to be Dracula, Vathek or the Monk, the best works of this genre have an enjoyably cathartic effect. They help us live with the horrors we sense out there, the horrors that we sometimes create, and the horrors that we are.