approach to science... as well as one of the most ambitious internet launches ever.

Stephen Wolfram has managed to keep more than a hundred "knowledge aggregators" secret while they've worked to collate the world's information, sucking factual knowledge from the Web into a giant electronic collective brain containing everything everybody knows. And because WolframAlpha is aimed at the general internet user, it's also had to learn a system of semantics, so that it can understand the "natural language" used by you or me when we ask it a question.

The concept is very appealing; partly because it¹s so close to the way we used to imagine computers, back in the 1950s and 60s: all-knowing intellectual servants, like Hal, in 2001: A Space Odyssey. But, in reality, how will WolframAlpha stay on top of ever-changing and expanding information? Google copes with around two billion search requests a day; how many will the WolframAlpha servers handle before they collapse under the pressure? Most important, how will WolframAlpha's reputation hold up after a single incorrect answer? Will we forgive it the way we forgive, say, Wikipedia,

its gaffes?

Expect the media ­ - obsessed as it is with finding a contender pugnacious enough to knock Google from its perch ­ - to focus on WolframAlpha's relationship with the big boys from Mountain View. But really the two will perform entirely different functions. Google's job is to search what we publish, WolframAlpha's to compute what we know.

So, for interesting and opinionated editorial about the causes of and cure for the current recession, Google will continue to lead the way. If you need to know highly defined and tailored economic data like ­ the relationship, say, between average US house prices and GDP ­ you might choose WolframAlpha for your data-crunching needs.

The big question is whether WolframAlpha will live up to its rapidly growing expectations... whether it will support Stephen Wolfram's controversial mathematical modeling theories, or turn out to be a quick and ignominious flop.

WolframAlpha launches in May 2009, at www.wolframalpha.com.