Economic journalists must walk a fine line.

Assuming they understand what they're writing about, they need to be able communicate that knowledge to a lay audience, a group of people who wouldn't know a New Classical from New Mexico

Then there's the matter of the economists and social scientists who do know something about the subject -- who help define the subject, in fact, Economic journalists, must write not just about the New Keynesians, but for the New Keynesians.

Hence, the fine line: the good economic journalist will write at a level that anyone can understand but that the experts will still want to read.

In this latest work, Economic Principals, David L. Warsh'66 demonstrates his masterful tightrope walking skills.

The longtime Boston Globe columnist is able to take complex aspects of econometric theory and make them simple. He is able to take dry debates over interventionist versus laissez-faire governments and make them come alive. And he does so without diminishing the level of debate ands scholarship behind the many conflicting theories and theoretical styles.

Economic Principals, a collection of Warsh's regular Sunday newspaper columns of the same name, highlights yet another mark of fine economic journalism: lasting relevancy. Some of the columns reprinted in the book date back more than a decade. But many are at least as interesting today as they were then--detailing debates ranging from Reaganomics to the application of mathematical modeling in the prediction of global economic trends.

Warsh puts economic history into a larger context of culture and ideas. In one essay, he links the Marxist theory of "Punctuates equilibrium" in economic evolution and Agassiz Professor of Zoology Stephen J. Gould's hotly-debated theory of punctuated equilibrium in evolutionary biology.

Marx used the concept of predict a proletarian revolution and the demise of the capitalist system. Gould, relying on similar principles of change in "Spasms," applies the view to a modern reworking of Darwinism.

Warsh's telling of economic history is interesting and informative. The technique he uses to best effect is the personalization of the academic--to show the principals behind the principles.

In this introduction, Warsh calls this the "social world of economics," It's world that includes interesting little tidbits perfect for cocktail party conversation--like the fact that John Maynard Keynes, the force behind interventionist government theory, was " a fairly promiscuous, always intense denizen of a hot-house society,"

That morsel is contained in chapter one, "The Sex Lives of the Great Economists," which draws a weird but engaging link between Keynes' bisexuality and his revolutionary economic theory.

"Is the sex life is great economics ever relevant? Well, yes and no," Warsh writes. "Certainly not in any everyday sense, but overall, there may be an element of sexual style involved in theory choice,"

But Warsh's "get personal" approach to economic journalism does not resort simply to visiting the bedrooms of prominent theorists. The book includes a catalog of snapshots from the lives of the last decade's Nobel Prize winners.

One of the best is the story of a brilliant but publicity-shy Norwegian economist who became a Nobel laureate in October of 1989.

"When the telephone range at Trygve Haavelmo's house in Oslo yesterday morning, there was none of the usual surprised-by-joy reaction of a fellow learning he has been awarded the $455,000 Nobel Economics Prize," Warsh writes. "Instead, Hsavelmo was vexed about being called at home. He told the Reuter reporter: I Don't like the ideas of such prizes. I'm not going to talk about this on the phone, and I haven't thought it through. Don't write anything." The 78-year-old theorist then went out and was not heard from for the rest of the day."

For followers of the Harvard economics scene, Warsh's book contains some fascinating tales of the politics of academia. There is the story of Baker Professor of Economics Martin S. Feldstein'61 and his rise to the top of his profession.

In 1977 Feldstein was appointed president of the National Economic Bureau, a focal point of economic research, "Feldstein has served as ringmaster to 130 of the best economists in the business, young and old; he probably has had more to do with defining the present-day concerns of his field than any others single man," Warsh writes.

But Feldstein has vocal critics, too, according to Warsh. "Lester Thurow, who himself was a candidate for the presidency of the Bureau in 1977, noting Feldstein's claim that a maharajah, receiving reports from five blind men feeling an elephant, could piece together an accurate picture, tartly compared Feldstein to a blind man suffering from the delusion of believing he was a maharajah," he writes.

Readers of Economic Principals will enjoy the backstage glimpses of "the social world of economics" that Warsh provides. Economists and economic novices alike will delight in stories like those behind Feldstein's prominence among the New Classical. And the novices, especially, will be glad to know that a New Classical is.