In a 1960 episode of The Twilight Zone, a character named Janet Tyler anxiously awaits the removal of her facial bandages. Describing herself as a “grotesque, ugly woman”, Tyler desperately wants to know if this, her 11th operation, has finally done the trick of transforming her from a “pitiful twisted lump of flesh” into something fit to be seen in public. The bandages come off and the doctors shrink back, horrified, into the shadows, shouting “No change! No change at all!”. Finally, Janet’s face is revealed to the camera: she is pure Hollywood blonde, part Doris Day, part Janet Leigh, encircled by medics who have the faces of diseased swine.

The episode is titled “Eye of the Beholder”: hardly subtle, but it made the point to a world still trying to find its postwar moral centre that ugliness is a cultural construct, local and particular, rather than a universal value. Yet it turns out that even such a relatively capacious definition won’t do for Gretchen Henderson, the author of this absorbing “cultural history” of ugliness. In particular, she is worried by the way that ugliness continues to be regarded as the fixed and eternal opposite of beauty: where one goes, the other is bound to follow.

It would be far better, Henderson suggests, to think of ugliness as a floating qualifier. Anything or anyone, in certain contexts, can become ugly, by which she means broken, unfinished or, to borrow a phrase from anthropology, “out of place”. And that, according to Henderson, who remains positively perky when discussing everything from hook noses to eating your own vomit, is just the way she likes it. Lining up behind Umberto Eco, who has also written extensively on the subject, she suggests that beauty is dull because it is closed, finished and always the same. Ugliness, by contrast, is infinite and everywhere, like God.

This is all kinds of clever, so it is a good thing that Henderson is willing to keep her examples rooted in the vernacular. As well as Lost in Space, we have “The Ugly Duckling”, Hans Andersen’s morality tale designed to teach children not to judge by appearances. Cinderella’s ugly sisters pop up too, although, confusingly, the moral of their story seems to be that surface and depth do actually match: the sisters are hideous precisely because they are wicked. Still, such conceptual asymmetry is perhaps an example of how ugliness, with all its lumps and frayed edges, can be pretty much anything you want, pressed into service whenever there is a point to be made.

And there are a lot of points to be made here, even if it is not always clear exactly how they all hang together. Better, then, to read this book not so much as an argument but a meditation, and to enjoy Henderson’s wide-ranging field of reference. We start, inevitably, with the Greeks, and their chilly ideas about marbleised physical perfection, before moving on to the Romans who were altogether better at getting in touch with their inner ugly. Here is Elagabalus, the second-century emperor who liked to invite eight unfortunates (“disabled people” we would probably say today) to dinner just to have a good stare. Over there is the speciality slave market, where having something odd about you – a huge nose, three thumbs, a leg growing out of your stomach – can push up your price, although unfortunately it is not you who pockets the profit.

From there it is on to the time of Middle English, where there are some wonderfully stumpy prototypes of “ugly” to conjure with – igly, wgly, oogly, ungly, hoggliche – before we land with a thump in front of Quinten Massys’s extraordinary painting The Ugly Duchess from 1513. Almost exactly contemporary with the Mona Lisa, the painting shows a spectacularly plain old lady tricked out like a gay young thing. Her headdress (wildly out of date) is elaborate and she holds a rosebud against her withered dugs. It is her face, though, that is truly shocking, not just its jowls, deep troughs and loose neck, but its animal shape, at once leonine and simian.

A Renaissance viewer would have had no hesitation in reading this as a face stuffed with lust and pride, belonging to a ridiculous old lady who thinks she can still pull. But, Henderson asks, if we are told that the nameless duchess may in fact be suffering from Paget’s disease, an unpleasant syndrome that artificially elongates the face, giving it an animal cast, then how does that affect our sense of our own smirking selves? Are we the ones who have, at a stroke, become ugly?

Using examples such as this, Henderson demonstrates the slipperiness of her subject. In the early 20th century, for instance, the French army put a ban on plug uglies becoming officers, convinced that capitaines with receding chins or bulging eyes would find it impossible to retain authority over their troops who might burst out laughing when asked to follow orders. But skip forward a decade or two, and the return of broken men from the front meant that ugliness, in the form of truncated limbs, lopsided faces and missing features, had become a badge of courage.

Nor did the process of cultural recuperation and rejection stop there. For it was in part due to the heroically mangled faces of the war-wounded that a new avant-garde aesthetic started to take shape, as French surrealists and German expressionists experimented with breaking down the human figure on canvas. The resulting explosion of jagged bits and pieces was, in turn, deemed “ugly” by the establishment and “degenerate” by the Nazis, before being reclaimed postwar as the moment when the 20th century finally found a visual language equal to the moral complexities of the modern world.

Ugliness, then, in Henderson’s generous handling, becomes a synonym for whatever is shocking, difficult, displeasing in one moment but reveals itself as containing real value and delight in the next. It is the cultural studies equivalent of kissing a frog. Hardly surprising, then, that when the Alice in Wonderland illustrator John Tenniel went looking for ideas on how to draw Lewis Carroll’s Duchess, he stopped longest in front of Massys’s Ugly Duchess. In those warped features and out-of-place geegaws Tenniel saw something more than an easy object of mockery. He had found the key to his Wonderland, a place where “uglification”, as coined by the Gryphon, meant far more than merely turning beauty on its head.

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