Every cave worth exploring has a dragon inside. Perhaps not one with claws and wings, and maybe this dragon does not breathe fire, but whatever its size or temperament, it menaces us from inside the cave. Meanwhile, we the adventurers stand at the entrance to that lair, the presence of the dragon cautioning us against crossing the threshold even as that same danger tempts us to explore. We need the dragon, the risk, the unknown waiting to be discovered to make the journey worthwhile.

When I was a child visiting my aunt on Vancouver Island, she and I embarked on a quest that ended with a dragon. She wanted to buy me a copy of Tolkien’s The Hobbit. I specified (in the fussy, determined way of adolescents, who tend to turn their every youthful opinion into a worldview) that I didn’t like book covers with stills from movie adaptations or representations of characters from the story. Both impeded my imagination from taking off, causing my reading to stumble as the mental image formed from the text tried to reconcile itself with the image on the cover. My aunt and I searched through several bookstores before ending up at Munro’s Books, where we found the copy of The Hobbit that still sits on my bookshelf. On its cover is a picture of Smaug the dragon.

Despite contradicting my no-characters rule, I loved this cover. Holding that paperback in my hands, anticipating the adventure it contained, I looked at that sleeping beast, curled inside his terrifying wingspan, glowing with internal rage and flames that illuminated the mountain of gold he guarded, and I felt like Bilbo Baggins – just as the Hobbit prepared to enter Smaug’s lair, I braced to enter the book. The dragon on the cover warned me of the danger inside while inviting me in.

That cover confirms my one rule about the outside of books, an inversion of the dictum to never judge a book by its cover: Always judge a cover by its book. That is to say, a cover’s primary inspiration, motivation, and thing it is in service to, is always the story itself. This is why those awful movie covers and covers that depict someone else’s idea of the characters are so bad – they impede the story from its task by undermining the imagination of the reader.

A few years ago, a new edition of Sylvia Plath’s haunting and lyrical novel The Bell Jar was published. It came with a garish pink cover seemingly designed by someone who thought, Written by a broad? Make it pink – and stick a picture of a woman using make-up on it. The little ladies love that stuff. This fails socially for the obvious reasons, but it fails as a book cover for having nothing to do with the text it purports to illustrate. It does nothing to signpost the kind of book to expect and does nothing to create an apposite atmosphere in which the reader can meet with the story.

Why would anyone – especially someone with the power of decision-making at a publishing house – greenlight such a cover? Probably because somebody thought it would sell, that it would attract readers who otherwise not pick up such a serious novel. This is the primary purpose of a book cover (and not, sadly for me, the manifesto for covers as artistic partners to the text that I just set out). As ever, it comes down to capitalism.

A BRIEF HISTORY OF BOOK COVERS

Until the 19th Century, covers were not a fixed feature of books and manuscripts were often left to the owner to bind as he liked. These early covers were therefore less reflective of the book’s contents than they were of the owner’s tastes and status. Many unread books acting as shelf decoration in private libraries had the most elaborate, expensive covers.

Gradually, books were published with uniform and uniformly dull dust wrappers that held the pages together and, if the publisher was flush, advertised their business. Dickens’ popularity afforded his serial publications the slightly more attractive (by the standard of the time; I find them hideous today) green covers illustrated with scenes from the story.

It wasn’t until the 20th Century and the rise of advertising that publishers saw the marketing opportunities in attractive covers. They began hiring artists and encouraging a new kind of commercial art. Which brings us to the present day, where the leading ethos behind cover design was expressed (no less reductively than the history presented here) by Tim Kreider in The New Yorker:

“1. Your product must be bold and eye-catching and conspicuously different from everyone else’s, but 2. Not too much!”

There is a short list of things a book cover might aim to do in order to sell the book. There are those that describe the book in terms of genre: thrillers with melodramatically large text and mysterious silhouettes, the close-up on the sword for fantasy epics, the minimalist white background, lowercase title, one abstract image suggestive of the theme for high-minded literary novels; every category of book has its sins. This is useful for narrow readers who simply want more of what they have already enjoyed. The desire for dollars, the primacy of pounds, goes a long way in explaining schlocky covers and why so many books look the same. They signal to the consumer that what they expect of a book, what they will part with money for, can be found behind this cover.

Occasionally, covers describe the book in more literal terms of plot. This has fallen out of favour, having been popular in the late 19th Century as with Dickens’ covers. Books for children still routinely go this route though. Then, of course, there are those covers that leave me cold by describing a specific setting or character from the book. Fundamental to each of these types of cover, though not the totality of their purpose, is the hope of enticing you to pick up the book and read it. Whatever the cover “describes”, it is also an attempt to convince you that this book is worth your time over the thousands of other, less attractive, books.

Classics, however, do not need to focus on convincing us to read them because they are, by virtue of being what we call “classics”, familiar enough that most readers seek them out, having a decent idea of what to expect within the pages. These books are better served by covers that evoke an atmosphere in which the reader can approach the text prepared for the kind of experience the book offers.

My copies of Frankenstein and Dr Jekyll and Mr Hyde do this well. They are large hardcover books that give traditional binding (no ugly, slippery dust covers here) a modern twist with unusual colours and repeated images – an anatomical heart for Frankenstein, test tubes for Jekyll. These covers suggest the timeless perpetuity of the stories. The quoted text from each book acts as a subversive form of blurb while endorsing the writing itself; these books stay with us not only for their plots but for the genius of the writing.

My copy of Conan Doyle’s The Lost World was picked up in a charity shop on the basis of its very simple, classic design. It allows me to forget any bells and all trimmings and be absorbed in the hidden world inside. The lack of any blurbs or hyperbolic, clichéd endorsements from famous readers is refreshing. (Let’s all agree a ban on the tired phrase “tour de force”.) Besides author and title, there is only a small picture, a stolen glimpse of a dense jungle, a hint of the adventure to come that draws me into the land described on these pages.

There are other, stranger ways that a cover can align itself with the text of a book, which are varied and can be quite specific to particular readers. One of them for me is to do with the colour of writing. A quick summary of two concepts: Synesthesia is a phenomenon in which an external stimulus produces an unexpected sensory experience – numbers are coloured, sounds can have smells. Ideasthesia is an extension of this, showing that it is not the objective nature of the stimulus but our conception of it that produces the sensory experience. So when a nonsense squiggle is shown to someone with synesthesia, they see no colour for it; when told that this character represents, say, the letter N, the person suddenly sees it having the colour they see for N. Ideasthesia shows us that just as physical stimuli, such as sounds and pictures, can cause sense responses, so too can ideas and concepts. In what might be a form of ideasthesia, passages of writing are strongly associated in my mind with vivid colours.

Words on their own do not have colours for me. As interesting and provocative as they are, lone words are incomplete pictures, fragments of a journey. It is in their relationship to other words – how they get on with their neighbours, what they have to say about the word before the full stop, how they alter the words that came before – that they come fully alive. This is when they take on colour. Books are often bathed in a dreamlike or peripheral hue; I feel and know the colour in my mind, but I could not point to its exact shade on a colour wheel. When I am working on a novel, I see the imagined totality glowing in a colour. This also happens when I am reading a book.

Zweig’s The World of Yesterday shifts between the blue of my hardback edition and a golden-mahogany – the colour of the text is in competition with the colour of the cover. Sometimes, the text has clearly decided the colour and the cover corresponds well. Often, the cover has conjured a colour for me – David Mitchell’s Ghostwritten is the exact burnt orange of the cover designed by Kai and Sunny – but it has got it exactly right, and imagining a different colour changes the text in uncomfortable ways. Occasionally, the colour of the text so dominates that the cover is entirely sublimated. Mitchell’s Black Swan Green is so definitively green, a sun-scorched viridescence that speaks of faded summer memories and fields of dry grass, that I was genuinely surprised to find, going to my copy while writing this, that the cover is bright blue with some gold. For years now I’ve been picturing my copy with a cover of that specific green.

The congruence of colour between the outside and the inside of a book is important to me because it avoids a dissonance that might not be insurmountable (we have all read and enjoyed books with unfortunately ugly covers) but whose absence encourages a better reading experience. And the concept of ideasthesia may have a lot to tell us about why good book covers, however you personally define that, are so important to our reading experience.

It is commonly believed that the words are all that matter in literature, whatever the typeface or page layout or cover binding it all up. So long as the words in their abstract sense are intelligible to us, we can engage with the text perfectly fine. In principle, there should be no difference between hearing the words out loud, reading them silently, or reading them from a book with this cover or that one. Perhaps this comes from the Romantic belief in poetry as an ethereal and “perfect” ideal. In a unique take on mind-body duality, we tell ourselves not to judge a book by its cover because however ugly the physical form may be, the abstract literature within might be beautiful still.

Traditionally, we have thought of reading as a process of taking input from the external world – the graphemes of a written text – running them through the machinery of our brains, and creating a mental representation of the external input. So, words on the page travel via the eyes through our brain and are “translated” into imagined pictures of what the words describe. When you read the word tree, that’s what you “see” in your mind.

Ideasthesia, however, expands and alters this view by showing that context significantly changes our perception of a thing. Ideasthesia is why many of us think of bright colours and italics as being high pitched, while dark colours and bold text are low pitched. It is why we think of certain sounds as “sharp”, blue as being “cold”, and smooth curves as more “relaxed” than jagged lines. Similarly, one sentence can be read in myriad ways and can conceptually signify different meanings:

“I love you”

and

“I love you”

and

“I love you”

carry very different meanings with nothing changed except the font on different words. We read those italics as emphasis, and that emphasis changes our perception of what the speaker is saying. Writers exploit these associations all the time, especially through word choice, because although a bellow and a scream can be synonymous, those two words conjure different sounds in our heads, one deeper and dark, the other elongated and sharp. But consider how a story might change with other forms of presentation.

I once tried to read Sense and Sensibility from a book using a futuristic typeface, which would have worked well with a sci-fi novel but failed to place me in Georgian England. The same applies to covers. A comic-sans title and a vibrant, brightly coloured cartoon on the cover will distract me from the dirty realism of a Chuck Palahniuk novel or the elegant prose and stuffy characters of Ford Maddox Ford. This is why the ostentatious, hallucinatory covers of sci-fi novels in the mid-20th Century are so memorable and why they excited readers of the time, because they matched the bizarre and imaginative tales inside those books.

Ideasthesia suggests that what we take to be great art is that which synthesises the conceptual with the experienced, a piece in which the ideas match what is felt. When a song examines heartbreak and the sheer sound of it makes you want to cry, this is that perfect fusion. When a novel describes a flight from danger and the word choice and sentence structure and paragraph shape make you nervous and giddy, that is the synthesis that ideasthesia implies. When a novel such as The Bell Jar wants to make us uncomfortable and look at pain unflinchingly and confront fears about our own sanity, a bright pink cover with a safe picture of a woman applying makeup undermines those goals.

While the cover alone can never make or break a novel, cannot determine its worth or artistic merit, it is one aspect of the conceptual whole that makes up the reading experience. It is no small feature, being the first thing you see when you take a book off the shelf. And the reading experience should not – cannot – be divorced from the text itself. Without readers processing the words and engaging at both a sensory and intellectual level, there is no novel to speak of.

Publishers and the designers they hire owe it to books to dress them appropriately for the job the book seeks to do. Perhaps we readers also owe it to our books to think a little more about their covers, and not choose the copy to own with no thought to the whole thing, or because we like the picture, or because it matches the room it will sit in, or the books it sits with, or the cover is part of one of the thousand collections Penguin puts out.

A book is more than any of its individual parts, but the whole is where a certain magic happens. The cover leads us inside, the pages enclose us, and the words come alive. And we become part of the reading experience, just like the atmosphere, like the typeface, and like the cover.

References:

• J.R.R. Tolkien, The Hobbit (1937)

• Sylvia Plath, The Bell Jar (1963)

• Tim Kreider, ‘The Decline and Fall of the Book Cover’ in The New Yorker (2013)

• Mary Shelley, Frankenstein (1818)

• Robert Louis Stevenson, Dr Jekyll and Mr Hyde (1886)

• Arthur Conan Doyle, The Lost World (1912)

• Stefan Zweig, The World of Yesterday (1941)

• David Mitchell, Ghostwritten (1999) and Black Swan Green (2006)