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But here's the really compelling part, the thing you'll call your friends about: Our first impressions, our unconscious preferences, are not stuck in stone. Many Americans show a preference for whites over blacks because our role models, the people we see around us, are white. But if you take some measures to expose yourself to minorities on a regular basis "and become comfortable with the best of their culture," Gladwell writes, your unconscious preferences will change. It's true that this sounds, at first, pretty naive: If you just accept the virtues of multiculturalism the world will become a better place, Koom Ba Yah. But Gladwell's argument is, he says, supported by research. You can take the IAT dozens of times and never change your score, but it turns out that if you look at articles and pictures about black leaders like Nelson Mandela and Martin Luther King Jr. just before you take the test, you'll get a different score. Your unconscious synthesizes the new information and, on the basis of just this little bit, comes up with a new opinion of African-Americans relative to whites.

Still, it's hard to know what to do with this news about how our unconscious works. As someone who has been tagged as having a preference for whites, I suppose I'd like to do as Gladwell says and fraternize with greater numbers of minorities so that when I want to "meet, hire, date, or talk with a member of a minority," I'm not "betrayed by [my] hesitation and discomfort." The thing is, though, I don't think I am often hesitant and uncomfortable around blacks; as far as I'm concerned, I think I behave normally around them. Gladwell's book makes a good case that I may be wrong and that I may be unconsciously displaying my unconscious preferences to the people I meet. But the peculiarities of his method -- that agreeable, undemanding prose style -- don't help to convince me that the situation's especially grave, certainly not grave enough to greatly alter how I live my life, not to mention to how we structure our society. In the end I'm moved to do not very much about the IAT other than just talk about it -- about how interesting it is, about how curious it reveals us to be -- and leave it at that.

If you're looking for one, this is the main flaw in Gladwell's work: He sees great meaning in the connections between many bodies of research, and he claims nothing less than that the meaning he has extracted could possibly change life as we know it. But in the end he's not very specific about how such changes will occur, or about how we should proceed in implementing the things he shows us. There are likely to be many readers who'll feel empty by the end, who will question whether the entire theory actually means anything or whether, instead, they've just been treated to a tour of Gladwell's really fabulous cabinet of strange wonders, and that all there is to do about it is discuss what they saw.

This is the hollow feeling one gets, certainly, from two of the most nominally serious parts of "Blink" -- its examination of wartime combat and of police work through the lens of rapid cognition. Gladwell tells us that it's better to fight battles spontaneously -- as Paul Van Riper, a legendary Marine commander, advocates -- rather than in a carefully orchestrated manner, as the U.S. military has done of late. And in a remarkable chapter, he probes the second-by-second tragic drama of the Amadou Diallo police shooting and concludes that the officers who killed Diallo succumbed to a failure of rapid cognition, a breakdown of their brains' ability to "read" Diallo's mind and infer his intentions. (Diallo was reaching for a wallet in his pocket, but the officers thought he had a gun and they unloaded their weapons into him, shooting 41 bullets.)

These sections provide intriguing narratives, and they do give us some basic outlines for how we might improve the military and police work. "Truly successful decision making," Gladwell writes, "relies on a balance between deliberate and instinctive thinking," and we could build a better military, he argues, if we created "an environment where rapid cognition" and spontaneity were possible. This is a rather vague proposal; Gladwell doesn't address the difficulties of integrating spontaneity into a rigid structure like the military, nor any ethical or political objections we may have to letting subordinates act on their own. In the section on Diallo, meanwhile, Gladwell suggests formally training police officers to deal with the sort of intense, acute stress that the cops faced the night they approached Diallo. "Mind reading" -- a cop's capacity to guess whether the man they're after has a gun or a wallet in his pocket -- "is an ability that improves with practice," Gladwell says. But would such practice have benefited the cops in the Diallo case? Could that shooting have been avoided if the police were trained as better mind readers? All that Gladwell has on this question is his own speculation; no experts support that view. And that's really all he can have, for there's no real evidence that such training would have saved Diallo's life.

But as I said above, to charge Gladwell with uselessness is to miss his intentions; clearly he doesn't mean to be useful, only interesting, and there he succeeds. Still, some folks will find much utility to "Blink" -- business people. Gladwell's fascinating chapter on how the complexities of rapid cognition interfere with marketers' ability to determine what we actually think about their products must, I imagine, be a hot item among CEOs at the moment. None of them would want to make the mistake Coke did two decades ago when it used the results of blind taste tests between its cola and Pepsi to decide that Americans didn't like Coke, and that it should develop a new (and ultimately failed) formula for its drink. But the truth, Gladwell points out, was that Americans didn't like Coke only when they sipped it blind -- and that made all difference. It turns out that when you see Coke poured out of the Coca-Cola can, and you drink a whole can rather than a sip, Coke tastes better. If the Coca-Cola Co. had only understood the mysteries of rapid cognition, it could have saved itself a great deal of money.

Perhaps this is what, in the end, will come of "Blink" -- Gladwell will save big companies from making stupid mistakes. Certainly "The Tipping Point" has given a great many firms insight into how to market to us, and if they're more successful now because of Gladwell, is there really anything so bad about that?

One request, though, corporate America: Don't start using "thin-slicing" in your press releases.

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