Leavis would have seen the words as self-contradictory. To him, books were moral self-improvement manuals, for earnest study at home. The idea of people relaxing with and even enjoying themselves with a book on holiday would have confirmed all his worst fears about a "levelled-down" civilisation in its last stages of decline.
But Holiday Reading has become part of the modern calendar. Bookshops promote Sizzling Summer Reads. Celebrities disclose what it is they're taking to Provence and Tuscany. And no self-respecting newspaper can deny its readers a Holiday Reading guide: if Christmas Books are the titles we choose as presents for others, Summer Books are the ones we are encouraged to buy for ourselves. Most bookshops and literary editors treat the exercise as a kind of mid-term report, listing the key titles of the first half of the year. But there's also a contentious notion that certain kinds of book are more suitable to take away on holiday than others.
Is it true? Are people's reading habits on holiday any different? Lighter, less demanding, more populist? If a vacation is (as the word suggests) a clearing out, does this also mean emptying the mind?
I'm not sure my own holiday reading habits are much of a guide. There was the wet Scottish camping holiday reading Robert Burns. There was the three-week honeymoon in Cornwall reading the whole of Anthony Powell's Dance to the Music of Time sequence. There was the excitement of reading a proof copy of Salman Rushdie's Midnight's Children beside a pool in Morocco in 1981. There was my parents' caravan in Wales, which ran to no more than Hammond Innes and Jacqueline Susann until I arrived with 130 hardback novels which I was supposed to be reading (and did, every word, honest) as a judge for the Booker Prize.
If that sounds eclectic, people I've asked about their holiday reading over the past week have also given a wide range of answers: "I take bestsellers - nothing heavy"; "I use holidays to catch up on stuff in my own research field"; "At home I'm too knackered to read at night - I fall asleep after two pages - so holidays are my only chance for sustained reading"; "In California earlier this year, I read John Diamond's C, Frank McCourt's Angela's Ashes and Gordon Burn's book about Fred and Rose West".
No simple consensus there then, either. But certain themes did recur, and agreed classifications of Holiday Read slowly became apparent. The seven types of congruity are as follows:
1 The beach book
Must be a paperback. A hardback takes up too much space in the beach bag and if you've forked out pounds 15.99 for it, you probably plan to take it home to put on your shelves, which it won't be fit for after a week's exposure to sand, salt water and sunscreen. Whereas in a paperback, any blemishes to the page aren't resented but are cherished like pressed flowers or petites madeleines, the source of sensuous recollection - this watermark from the Aegean, that lingering whiff of lotion. Paperback, then, and preferably fiction. If non-fiction, it needs to have a strong narrative line, so that after the inevitable interruptions (adjusting parasol, coping with screaming toddler, having sand kicked in face by partner or by person who fancies your partner) you can quickly pick up the thread again. Definitely not Jackie Collins or Jeffrey Archer, if you want some intellectual cred (and you do, you need it badly, it's your only hope, look how much thinner/younger/more tanned everyone else's body looks round here). But not Wittgenstein or Nietzsche, either (you don't want to scare people away). Anne Tyler, Nick Hornby, Dana Sobel, John Irving, Beryl Bainbridge: these will do fine. Of course you could take Captain Corelli's Mandolin but you read that last year, or if you didn't you might as well wait for the film. Books with sand in the plot may provide an extra grain or frisson of authenticity - T E Lawrence, maybe, or Paul Bowles's The Sheltering Sky. Better still, because this allows you a sly self-referential joke that will impress any post-modernists in the vicinity, are books with the word "beach" in the title - William Boyd's Brazzaville Beach, J G Ballard's The Terminal Beach, Ardashir Vakil's Beach Boy, Nevil Shute's On the Beach, Alex Garland's The Beach and even (if in a Leavisite mood) Matthew Arnold's poem "Dover Beach" are all possible, although some of these more properly belong to the next category, ie:
2 When in Rome ...
Immerse yourself in where you are: one of the great unacknowledged pleasures in reading lies in coming across descriptions of places you know or can visit. You will have the guidebooks, obviously, but remember the travel writers too: Redmond O'Hanlon for Borneo, Colin Thubron for China, James Dalrymple or Mark Tully for India, Dea Birkett for Pitcairn (how on earth did you get there?), Paul Theroux for just about anywhere. Better still, take topo-sensitive novels: James Joyce for Dublin, Arundhati Roy for Kerala, Louis de Bernieres for Greece. Maplike accuracy isn't necessary. A temperamental affinity will do - Anita Brookner for spa towns and lake resorts, Malcolm Bradbury's Rates of Exchange and Kazuo Ishiguro's The Unconsoled for trips to Eastern Europe, Kafka for the queues at US Customs and Immigration. If on the beach (see above), read The Beach.
3 The On the Road book, aka "the picaresque"
This is a book (usually fiction) recounting an adventure or series of adventures en route. Essential for hitchhiking holidays or overland treks, when hours of boredom can be better endured by reading about others in the same boat, bus, car, mule-cart. Kerouac is hard to beat, but try also Hugo Williams's No Particular Place to Go, and Robert Pirsig's Zen and the Art of Motorcycle Maintenance. Don't stick to this century: look further afield to Don Quixote, Tom Jones, The Decameron, The Canterbury Tales. If you are backpacking and none of these is available, read The Beach.
4 The classic
How many years is it now you've been promising yourself to read Proust? Dostoyevsky's Crime and Punishment: of course you've read it once, you distinctly remember the scene where whatsisname ... but why not reread it? Brideshead Revisited? Jane Austen? Did you really read them, or just watch them on television? To make your choice, play Humiliation with friends: the object is to name the most famous book you've never read. Don't be ashamed of your shame, use it to decide what goes in the suitcase. If the outcome really is too daunting - if, for example, the most famous classic you've never read is the Bible - remember that bookshops now offer sections of modern or contemporary classics, among them The Catcher in the Rye, A Clockwork Orange, Lord of the Flies, To Kill a Mockingbird and (probably) The Beach.
5 Thrills and spills
These days an increasing number of people are going in for activity holidays: hang-gliding, mountain-climbing, white-water rafting, deep-sea diving, bungee-jumping, etc. Though well-written books about these activities are notoriously hard to find (most authors being sedentary wimps), intellectual equivalents are not. Seek out something that looks strenuous or unfathomable. Peruse the dust-jacket for comments such as "vertiginous" or "acrobatic". A narrative so dense you can get lost in it is recommended for orienteering holidays. Bumpy plots will suit mountain-bikers. Cliffhangers go down well in the Alps or Pyrenees.
6 The book as fashion accessory
Certain books it's enough to be seen with; if you decide you want to read them, fine, but don't feel under any pressure about it (you're on holiday, aren't you?), and if you really find yourself hooked, make sure to recline face-up on a sun-lounger so that the title and author are clearly visible. Think hard about your choice: does Hannibal give out the right signals? Is it wise to read Lolita? This season's coolest bookwear is Cormac McCarthy or Annie Proulx. The latter will give you a chance to engage others by asking: "Do you know why she dropped the E?"
7 The book for children of all ages
If your knowledge of philosophy came from reading Sophie's World, you secretly prefer Just William or The Famous Five to Germaine Greer, and you are addicted to Point Horror or Spot the Dog, don't worry: other parents suffer the same malady. A strict regime of titles such as Maritime Supremacy and the Opening of the Western Mind or The Potato: The Story of How a Vegetable Changed History usually effects a cure. If not, give in and buy the new Harry Potter, which is published this Thursday at 3.45pm. But remember to let your children read it first.
Harry Potter, incidentally, will be going in my suitcase, along with Jane Rogers's new novel, Island, Jared Diamond's Guns, Germs and Steel, Michael Hofmann's poems, a proof copy of Giles Foden's forthcoming Ladysmith, some ancient tomes on Johann Gutenberg (600th birthday next year), oh, and probably - I liked it a lot when I read it the first time - Alex Garland's The Beach.