Malcolm Gladwell: A good hair day

He has been called "the darling of New York's literati and the toast of corporate America". He's "the most talked about magazine writer since Hunter S Thompson". "A rock star. A spiritual leader. A stud", even. Yet when people meet Malcolm Gladwell, he's often not what they expect. "I have an old man's name," he explains. "They imagine me to be this tweedy, white-haired guy."

The reality is a 42-year-old who could pass for 30, with a spirited Hendrix afro.

Preconceptions loom large in Gladwell's latest book, Blink, a pop-sociology tour de force about how first impressions affect decisions and the power of snap judgements. Blame the hair.

The idea for Blink came after Gladwell abandoned his side-parting and let nature take over. Soon he was getting pulled out of airport security lines and given speeding tickets. One day, walking down 14th Street in Manhattan, he was jumped by three policemen. After 20 minutes' interrogation, they decided he wasn't the rapist they were looking for. Their first impressions - based on hair alone - had been enough to blind them to the facts that in build, height and age, Gladwell was nothing like their man. In fact, argues Blink, first impressions are so powerful they can ascertain whether newlyweds will wind up divorced, spot a forged Grecian antique and prompt Coca-Cola to launch a disastrous new drink. They also explain the enduring appeal of Tom Hanks. It's all very Gladwell.

"I describe my books as intellectual adventure stories," he says, arranging his man-boy limbs on a chaise longue in his West London hotel. "It's a romp. And one of the characteristics of a romp is that you take the readers to as wide a variety of places as possible." They clearly appreciate it: Blink has remained on the bestseller lists since it first appeared in January 2005. It's been translated into more than 25 languages and sold 1.3m copies in the United States alone. Leonardo DiCaprio's production company has just spent a million dollars on the movie rights. (DiCaprio is expected to star, with a script by Gladwell and Stephen Gaghan, screenwriter on Syriana and Traffic.)

Gladwell's first book, 2000's The Tipping Point, made such an impression that the title has been used by everyone from Donald Rumsfeld (describing the Iraq war) to rap band the Roots (their 2004 album). Last year, Time magazine named him one of its 100 Most Influential People.

What Gladwell does is knit together big social science theories, showing their relevance to our everyday lives. Translating academic work for a popular audience, he has said, is "very explicitly" his mission: "Take away the psychology departments of half a dozen universities and Blink doesn't exist." But this is selling himself short.

Gladwell is a virtuoso writer. His website notes that "to my mind, the written word improves [when] it comes to resemble the spoken word", and such refining is no small feat.

The Tipping Point, for example, demonstrates how trends behave like viruses: Gladwell's glee at zipping from everyday examples, such as the decline in New York crime in the 1990s to the retro vogue for Hush Puppies to the influence of book clubs on sales of Divine Secrets of the Ya-Ya Sisterhood, is infectious. He's the cool teacher you had at school. He makes clever stuff fun.

"I'm a synthesiser of ideas," he says. "Most of what I'm doing is piggybacking off other people's ideas. But I will say I don't think that's a trivial role." Book publishers agree. Since The Tipping Point, the pop science genre has exploded; such titles as The Wisdom of Crowds, Everything Bad is Good for You and Freakonomics are doing brisk business.

Gladwell's day job is as a staff writer at The New Yorker. Contracted to produce 50,000 words a year, he's given free rein, something that has led to dozens of dazzling, counterintuitive articles well aware of their own audacity. "Are smart people overrated?" he asked in "The Talent Myth". "Why homelessness may be easier to solve than manage," he proposed in "Million-Dollar Murray". Others have revealed how shopping malls work, riffed on kitchen appliances, nappies and khaki trousers, and, on one occasion, spent 5,400 words explaining why there's only one type of ketchup, but tens of varieties of mustard. That one took two and a half months to write.

"It was a fairly high-risk piece," he smirks. "But there has to be a certain degree of difficulty, otherwise you're just churning it out. As a writer, my most important criterion has been: would this be a story I would enjoy writing? If I find it interesting, chances are other people will too."

Gladwell's writing is crammed with poppy buzz-phrases. The "mavens", "connectors" and "salesmen" of The Tipping Point. "Rapid cognition", "thin-slicing" and "the Warren Harding Error" in Blink. His ability to decode our behaviour has made him irresistible to businesses. He was recently rated No 27 in a list of Top 50 Business Gurus, and gives around 25 lectures a year to companies such as Google, Microsoft and Hewlett-Packard. It pays better than journalism: fees of £20,000 a talk are bandied about.

How has Gladwell done it? A New York Times profile quotes his father, Graham, saying he was "obnoxiously competitive" as a child. This makes him guffaw. "I think that's probably accurate," he says. "I had big dreams as a kid."

Born in England and raised in rural Canada by his Jamaican therapist mother and English maths professor father (both published authors), he was reading the Bible by six, perhaps because the Gladwells had no television. A "right-winger" at college, he slept with a picture of Ronald Reagan above his bed. He excelled at running. He graduated in history from the University of Toronto but says he was so contrary he "didn't make it easy" for his professors. Unable to land a job in advertising, he worked at The American Spectator then The Washington Post, arriving at The New Yorker in 1996 as then-editor Tina Brown was transforming it from fuddy-duddy 1920s institution into something more contemporary. The Tipping Point grew from an article of the same name.

Today he lives frugally in his West Village apartment. "I'm slightly baffled by my prosperity," he mumbles. "I'm not sure what to do with it." Despite being "obsessed" with cars, notably Porsches, he has "zero interest" in owning one. Writing, he says, is confined to around two hours a morning, leaving plenty of time for sleeping and, presumably, thinking. Recent articles have leaned more towards the political (homelessness, health care), though he says he's angered by the usual things: "the war in Iraq, what an idiot George Bush is, global warming". But it's the everyday that really gets him going.

"Take fashion," he says. "People always want you to write about Valentino. But it's so much harder and more interesting to write about Gap."

'Blink' is out in now in paperback from Penguin.

Blink: The Power of Thinking Without Thinking

In Blink, Gladwell explores the mind's ability to make split-second decisions. He calls this "adaptive unconscious" or "the power of thinking without thinking". He describes the idea of "thin-slicing", our ability to gauge what is important in a fraction of a second. Spontaneous decisions are often better than pre-planned decisions, he explains, though our ability to "thin-slice" may be thrown off by prejudice or stereotype.

The Tipping Point: How Little Things Can Make a Big Difference

The title is a sociological term that refers to the moment when something underground goes overground. Gladwell explains that "social epidemics" - the popularity of a style of shoe, teenage smoking - follow the same mathematical pattern as viruses. He identifies three types of person with the ability to produce social epidemics: connectors, mavens and salesmen.