From PEOPLE Magazine Click to enlarge
Helen of Troy's face may have launched a thousand ships. But nowadays she'd be lucky to fetch three nearsighted sailors in a skiff. Imagine the ancients' idea of beauty: skin white as new-fallen snow, lips red as Parthian leather, a proboscis like an arrowhead and, most prominent of all, eyebrows that formed a single delicate arch of fuzz growing together over the nose. As Woody Allen once put it in a classically inspired poem: "True, Homer was blind, and that I accounted for why he dated those I particular women."

It's an indisputable historical fact that standards of beauty are as whimsical, cruel and ever-changing as the stock market. Take that current exemplar of high style and attractiveness, the society matrons dubbed "social X rays" by Tom Wolfe in The Bonfire of the Vanities. Preternaturally skinny, they seem thinner in direct proportion to their husbands' wealth. The prosperous burghers of Rembrandt's day, who liked their women ample, would have fled them in horror. But both ideas of beauty share a certain logic: In the 17th century, when famine was still widespread in Europe, rich merchants wanted their wives to reflect the bounty of their tables; now that we're inundated with cheap, fattening foods, it's the poor who are often portly, while the well-off work it off at gyms.

Tantalized by the enigmatic nature of beauty, scientists and artists have long struggled to define it with a formula. Ancient Greek mathematicians calculated that the ideal face was two-thirds as wide as it was high. In his famous anatomical drawings, Leonardo da Vinci showed that the proper human form, with arms and legs extended, generated a perfect circle and square. (Unfortunately, as art critic Kenneth Clark has noted, the body type that best fits this model is that of a gorilla, not Homo sapiens.) More recently, University of Louisville psychologist Michael Cunningham, quizzing young men on the charms of various Miss Universe finalists, came up with the following figures: eye width three-tenths the width of the face, and chin length one-fifth the height of the face.

Like beauty itself, the idea of what is pleasingly plump has changed constantly over time. For both men and women, observes art historian Anne Hollander, rotundity was considered appealing from roughly 1500 to 1900—presumably because girth was equated with health and affluence. Botticelli's exquisite Birth of Venus, painted circa 1480, has a slightly unseemly heft by modern standards, but she's svelte compared with Rubens's Three Graces of a century and a half later, who resemble Roseanne Barr in concert with the voluminous 1980s singing duo Two Tons of Fun.

Though the precise distribution of the desired fat fluctuated widely over time, from busts to bustles, it was common well into the 1800s for everyone from prostitutes to well-born socialites to pad their bosoms, hips, arms and thighs. Some of the padding involved inflatable rubber devices called "gay deceivers," which, writes Lois Banner in her book American Beauty, "occasionally popped at parties, creating merriment among the partygoers and mortification for the wearer." Ideally, the padding was natural. Asked whether she was happy, one Connecticut cutie of the late 1800s was quoted as replying, "Oh! Immensely! I have gained 18 pounds in flesh since last April."

The Victorian ideal of the pale, delicate paragon, more ethereal (and unthreatening) than sexual, was the first major challenge to the buxom beauty. As early as the 1830s, Harriet Beecher Stowe was complaining, "If a young lady begins to round into proportions like the women in Titian's or Giorgione's picture ... she is distressed above measure." While ample-ness still reigned on the stage and in the dance halls, here too tastes were changing. Statuesque actress Lillian Russell began an epic, heavily publicized diet à la Oprah Winfrey after one reviewer in 1896 compared her ungallantly to a white elephant.

Once fears of food shortages diminished with the new century—and with them the age-old idea of carrying extra fat in reserve for emergencies—a new aesthetic emerged. The athletic Gibson Girl, whose turn-of-the-century form was unfavorably compared by one critic to a telephone pole, came first, followed by the cigarette-thin flappers epitomized by '20s actress Clara Bow. (Scholar Hollander speculates that the cinema helped popularize thinner figures because the camera loved pronounced bone structure.) A diet book first cracked the best-seller list in 1918, around the time that champion swimmer Annette Kellerman, the Esther Williams of her day, began bullying American women into slimming down. " 'Fleshiness,' 'obesity,' and 'embonpoint' are only soft-pedal euphemisms, "jeered Kellerman. "It is fat just the same." Kellerman herself stood 5'4" and weighed close to 140 lbs.—hefty by today's standards.

Ironically it was the male body, all but eclipsed in recent times by the female form, that was the original standard of beauty in Western culture. The first Olympic athletes, extolled by poets of the day as beauty incarnate, wore skimpy bits of drapery like that of the famous Greek statue Apollo Belvedere; in succeeding centuries men of wealth and rank—with their ruffles, brocades and fancy wigs—were often as plumed as peacocks.

With the coming of the Puritan work ethic and the industrial age, however, it became unfashionable for men to admit to an interest in appearances—no doubt because they should have more pressing matters on their mind. The ideal male image was projected by such manly movie stars as Gary Cooper, John Wayne and, more recently, Robert Redford, with his natural, sun-burnished allure. But for both sexes a major change in beauty consciousness is underway. Masculine vanity is making a big-time comeback. Men now race women to the Stairmaster machine at the gym, equally eager to sculpt the tight bodies that drive the other sex wild. A still more epochal change has accompanied the aging of the baby boomers. Instead of hiding their baldness, some men now flaunt it, growing gray ponytails in back like Ringo Starr's. Women, for their part, are permitted what was once unthinkable: more than 40 birthdays. The married-and-settled-down Hugh Hefner has featured a gorgeous 50-plus nude in his magazine, and the Disney studio has made an outrageous fortune by investing in such actresses as Bette Midler, whom Hollywood once presumed beyond the pale.

Now, in our age of couch potatoes, it's already hip to be square; next it will be hip to be round. The generation that began, in the '60s, with mind expansion has settled into waist expansion, and Tom Wolfe's social X rays may well fade from the picture. Who knows? One day soon, our standards of beauty may even cease to exclude most of the human race.