The chat in the air this week is about the seemingly exhausted topic of Gary Hart and Donna Rice. The reason is a probing piece of work in Vanity Fair (September), by journalist Gail Sheehy, called "The Road to Bimini."

Swift reading even at 12,500 words, the story describes Sheehy's travels through "the various worlds of Gary Hart," inviting people who know him -- or thought they did -- to speculate about why he spent his lifetime compulsively putting himself in jeopardy. Hart's sister Nancy Lee frames the problem in concrete terms. "Why would Gary give up something like Lee for that lowlife ... a twenty-nine-year-old tramp?"

Sheehy's sketch of Donna Rice's world is poignant in its own right: nomadic clutches of naive and ambitious young women burning up their lives as decoration and company to moneyed and, occasionally, important men. Rice's father, in a tense telephone exchange with Sheehy, blurts out, "What was she doing in New York to make a living? Have you got some information indicating she was a hooker?" (Sheehy does not.)

Say what you will about Sheehy's bestselling "Passages," it did seem to make sense to people, and the evidence of her work on Gary Hart in this magazine confirms a gift for making other people gab, and for making imaginative connections and judgments about what she hears.

It was Sheehy who got Hart to talk about his personal mystic, Marilyn Youngbird, in 1984, at a time when he thought he might really become the next president of the United States. When Youngbird told Hart he had been chosen "to save nature from destruction. It's your time," he admitted to Sheehy that he believed this to be true.

"How could a man so dangerously flawed," Sheehy wants to know, "come so close to persuading us that he was fit to lead a superpower through the perils of the nuclear age?" That's one question she doesn't answer. She doesn't even come close, frankly, but she leaves us asking the question of ourselves, about this politician and others.

Also of special interest in this issue of Vanity Fair is a rare coincidence of lucidity and approbation by Christopher Hitchens -- an interview/review about Michael Kinsley, editor of The New Republic, and his first collection of columns -- and as unclouded a glimpse of Diane Sawyer (by Michael Shnayerson) as has appeared in many, many published tries. A question, though: However pleasing she may be to the eye, why does a respected professional surrender to the urging that she pose for come-hither photographs?

Mirror, Mirror Taking a page from a recent issue of GQ, which published a list of 99 things a man should know by the time he turns 30, Cheryl Russell, editor of American Demographics, offers a list of "things you should know, no matter what your age, if you want to keep up with trends."

On the list are some good myth-dispellers, like "Two-thirds of working women work full-time" and "Eighty-five percent of Americans live in families." Why, though, is it important for the model citizen to know that "The occupation that will gain the most jobs in the next ten years is cashier."

American Demographics is evolving into a brighter mode these days, without shaking its serious attention to the significant data that compose the national mirror. In the August issue, for instance, Bickley Townsend and Martha Farnsworth Riche disclose that America's two-paycheck families come in more varieties than the acquisitive, child-postponing, soulless you-know-whats of current lore; there are seven distinctive species, in fact.

Even feistier in the public pulse-taking business is Public Opinion, a bimonthly magazine published here by the American Enterprise Institute. The July/August number is all about prejudice and its changing patterns, with essays on the relative biases against Jews and blacks, new forms of anti-Asian feeling, homosexuals in the AIDS era, and television's representations of minorities.

Victoria Sackett, in a clever piece called "Discriminating Tastes," opines that the growing acceptance of ethnic and other forms of diversity has channeled people's natural venom into individual, and usually more benign, exercises of misanthropy -- intolerance of the brainless twits, insufferable bores and egregious morons (and, of course, cigarette smokers) who cross one's path every day. Sackett has no data to bolster this theory, but it sounds right.

Just as compelling as the articles in Public Opinion is the regular centerfold, if you will, of tables and graphs depicting demographic statistics, allowing you to make your own extrapolations. The patterns of change -- and stasis -- that emerge from soundings of American prejudice from 1948 to the present are eloquent even in their wordless state.

Table of Contents What the milkman delivers every morning to Michael's Restaurant in Santa Monica bespeaks its culinary priorities: 6 gallons of milk, 4 gallons of half-and-half, 18 gallons of heavy cream. Such scrumptious details are revealed in Eric Mankin's day-in-the-life-of-Michael's story, published in the August issue of the fun-loving L.A. Style. One key to the flawless service at this famous restaurant: waiters are on salary, paid from obligatory 18 percent service charges. Total tab for a party of seven the evening Mankin was there: $768, including $219 for wine. But arms merchant Adnan Khashoggi once spent $2,700 for a party of eight; he ordered better wine.

Writing in the September American Photographer, Carol Squiers accuses the nation's magazines of timidity in their assignment and choice of photographs. Even as photojournalism prospers anew in America, she contends, editors remain more squeamish by far than their European counterparts about publishing the most evocative depictions of personal character and human tragedy. The sensitivities of advertisers and "old-fashioned Yankee decorum," Squiers writes, are responsible