"Now, Kissinger is a kind of international tipster. He comes around and whispers in your ear, 'Buy Iran . . . . Sell South America' . . . ."

In the hands of Lewis H. Lapham, editor of Harper's magazine, the metaphor is a deadly weapon. He knows this. He believes it is a way of dispelling the aura of magic we use to avoid thinking about our problems. For him, it is a lightning rod that brings the heavenly bolts literally down to earth.

Addressing a conference this week on the energy crisis, he dazzled a roomful of oil executives with his elaborate comparison of American wealth to a family estate, which in the '60s was the subject of a quarrel over its division.

"Money is the weapon of the parents, and journalism is the weapon of the angry child," he speculated, and he went on to characterize the servants, the gardeners, the steward who sold the family assets (that would be the unfortunate Kissinger) and so forth.

At 44, Lewis Lapham is an anomaly in American pop letters. Scion of a solid-gold San Francisco family, educated at Hotchkiss, Yale and Cambridge, he broke away to become a reporter for the San Francisco Examiner at a time when being a Yale man, let alone a Lapham, was taken as a personal insult by every old city room hand.

Coming by degrees to Harper's, he found himself an editor in 1971 when most of the staff quit along with editor Willie Morris. By 1975 he was in full control of the 129-year-old liberal monthly.

And things began to change.

"We'd had four editors in 15 years, each with a different bias," he said. "The readers were all divided. It takes a couple of years to sort out each change. But I think now they get the hang of it."

Circulation has doubled in the past three years at Harper's, even though the price was doubled too. Still, at 300,000, it is down 10 percent from 1975. In taking the magazine from basically the left to basically the right, Lapham has lost a lot of readers and picked up a lot of other readers, and also changed the minds of still other readers, he's not sure how many.

How do you turn a magazine around?

It's not at all a question of party line, but of personality, he says. For one thing, he has moved the old editor's "Easy Chair" essay up front from the back of the book and has changed it from the traditional Edwardian essay on cattails to a statement of belief. Sometimes he throws a little acid, too. It is still a bid Edwardian in its insistence on elegance. Mostly it is startling in its originality of idea.

"By reducing the ambiguities of history to the simplicity of fable, the media transposes both the past and the future into the miraculous present," he wrote recently. "Not even Walter Cronkite can remember in June what he was saying in January."

The beauty of having the editor write his own column, he observed in an interview here, is that "you don't have to make your own points subversively in the writers' copy." With his small staff, he does little rewriting, depends largely on name writers, avoids the pitfall of the politician's position paper, scripted by the great man's aides, which must be turned into prose.

Articles emerge basically from conversations. The writer is given a mission, say, to do a negative piece on Carter at the peak of his popularity just after the election (or conversely a positive piece on him today -- Lapham having a kneejerk reaction to unanimity), and if it doesn't work out that way on the writer's return, "well, we talk. Maybe we scrap the whole thing."

There is an attempt to keep some sort of balance, but it is no fanatic measuring of column-inches. When a pro suggests that "I can do you a think piece on such and such," Lapham winces (privately, that is, for the still face and the soft voice do not change, any more than does the dark blue suit glow red) and asks what the writer thinks. "Try it in the first person," he may say. That gets 'em.

In a word, he says he is trying to get back to the disaffected, apathetic, alienated private person whom we call the public. He is tired of the posters we put up around us, the two-dimensional symbols, the codewords with which our leaders abstract our lives and problems.

"Our leaders don't have a vision of the future," he says.

His articles, and others in Harper's today, constantly deal with delusions: the people's inflated expectations for the press and the presidency, the need to believe that they are electing God or at least a shaman (a very Harper's word) who will magically solve their dilemmas, the putative answers contained in government, the foolishnesses of conservationists, et cetera, et cetera (also very Harper's).

A baffled Time magazine recently called Lapham "an aginner," and he is that, and so is Harper's. Very little goes well in the world of Harper's, and it is hard to say whether the untried new idea or the tried-and-wanting old idea gets the worst of it. Slightly stung by an accusation of humorlessness, he has been injecting more wit into the mix.

"But it's got to be dry," he said. "It can't be Shel Silverstein.It's gotta draw a little blood."

No one ever accused Lapham himself of lacking in wit. "Mr. Carter," he wrote once, "was elected to redeem the country, not to govern it . . . . His administration of virtue stands as a testimony to the vice of the times, which, as even schoolchildren know by now, is the preoccupation with self."

His audience, he says, Harper's new audience, "starts on the other side of the Hudson and ends just before you get to Los Angeles." If he is talking about Middle America, that is a pretty big middle, and it is filled up to here with disaffected, apathetic and alienated people. If he can just get them all to buy Harper's, he's got it made.