SOMETIMES YOU JUST WANT TO LIVE inside a book. In Paris this can happen quite literally, thanks to what might be the world's most exciting bookshop: Shakespeare and Company. Originally opened in 1919 by Sylvia Beach, who published Joyce's Ulysses and bankrupted herself in the process, the shop in its present location, overlooking Notre Dame, was revived in 1951 by a romantic American bibliophile called George Whitman. George is still alive at 94, but the shop is now owned and managed by his powerhouse 28-year-old daughter, Sylvia Beach Whitman.

The ethos is as it ever was - two floors of books of every kind, new and second-hand, and a library for browsers, along with a piano if you feel like playing it. The books are all English language, and the place is open every night until 11pm, staffed by fresh-faced and optimistic twentysomethings from around the world, who work in the shop for a few hours a day, and undertake to read a book every day too, in return for a bed every night. No need to sleep with a book under your pillow when your book is a pillow; there are 11 beds hidden in the bookshop itself, like secret finds in a child's puzzle. By day they are neat and discreet, by night, not just ZZZZs but all the letters of the alphabet swarm above the heads of the hard-working dreamers.

So I planned a quick escape on Eurostar, to read, walk along the Seine, and play with whatever language tapped out from under my fingers when a different language was ringing in my ears. I had reckoned without the transport policies of Little Britain.

Here, travelling by public transport on a Sunday is like being an extra in The Incredible Journey. There was no direct train from Oxford to London Paddington, only a

“replacement bus service”, as they put it, strangling the meaning along with the passengers. Unable to face a coach to Reading, that Kremlin of the railways, I tried to get a scheduled bus all the way to Paddington, but discovered that the Park and Ride allows only 72 hours of parking, a strange alchemical number, after which the car is turned into gold in the shape of a £120 fine.

Park and Ride...what doomed creature redefined those words that should evoke green space and freedom, and jinxed them in a dead lexicon of asphalt patrolled by werewolves with wheel clamps?

Anyway, Sartre was right: “L'enfer est les autres.” Buses make me sweat with feral anxiety like a wild thing caught. To me, spare cash is about transport, and I spend as much as I can on it - or nothing at all, preferring to walk two hours across London to preserve my space; space to think, watch, feel. I find the press and rush of others difficult. I know that I am a bit odd, but I would rather be odd than compliant.

So I drove myself to London, where a kind friend let me park in her space, allowing me to catch the Eurostar with ten minutes to spare and a copy of A Dangerous Liaison, Carole Seymour Smith's new biography of the relationship between Sartre and de Beauvoir.

It is only two years since Hazel Rowley's excellent Lives and Loves appeared, but that book is kinder, more sympathetic, and perhaps less tough on the two French giants of culture. A Dangerous Liaison is one of those take-apart-the-engine types of biography, with no care for the damage done to the vehicle, the vehicle being the work, which is really the only thing we can legitimately ask of a writer.

The trouble with the fashion for exposing everything - yes, everything - about the lives of writers and artists, is that no one, genius or window cleaner, can survive such a process. Inevitably, a biography such as this plays to the envy and inertia of those hellish others, who, achieving little themselves, froth with delight at the failures of those who have made a difference. For all the sex, power, drink, arrogance, failure, and compromise, Sartre remains a hugely important cultural figure. Contradictions and oppositions lie side by side and do not cancel each other out. I read the best of him, skip over the rest, but A Dangerous Liasion might encourage new readers and students to skip it all - and feel justified. A pity.

Anyway, reading Sartre - prolix, annoying, French - requires much less effort than travelling by public transport in the UK on a Sunday. Who says that culture is elitist?

A Dangerous Liaison by Carole Seymour-Jones (Century), £20, offer £18

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