When a Washington think tank invites scholars, policy wonks and journalists to hear an intellectual propound a new economic theory, it's not often that the work under discussion comes recommended by Elle.com. Nevertheless, Elle, a magazine of beauty, fashion and style, describes the latest book by Virginia Postrel as the "must-have accessory."

Women - and men - who rarely pause to accessorize crowded into the conference center at the American Enterprise Institute, a conservative think tank, to listen to her talk about her provocative new book, "The Age of Aesthetics: How the Rise of Aesthetic Value Is Remaking Commerce, Culture & Consciousness."

Postrel, a libertarian intellectual who is the former editor of Reason magazine and an economics columnist now for the New York Times, finds dynamic intersections of politics, economics and technology. These are intersections that many of us have walked past without recognizing.

"Rising incomes and falling prices mean we can buy more of everything, including aesthetics," she says. The rich who want to hide the toilet-cleaning brush in chrome and crystal for $400 are on the same "wavelength' as the customer who buys a Michael Graves toilet brush at Target, with blue handle in a white translucent container, for only $8. In both cases the eye chooses pleasant surfaces to make the toilet less a reminder of its utility.

"Competition has pushed quality so high and prices so low that few manufacturers can survive on performance and price alone," she says. They must give customers something to please "their sensory side."

She celebrates the pleasure enjoyed by fashion styles from cosmetics to cosmetic surgery, from haut couture to rip offs in cheaper materials, at Wal-Mart and Target. She rails against moralists who see luxury as the root of evil, who scorn capitalism for creating illusionary incentives for people to buy what they don't need.

A craving for beauty, she insists, rests on a hierarchy that begins long before the stomach is full and a roof is securely on the house. When women manage to leave the welfare dole, for example, they dress better. They have more money, of course, but style reflects renewed confidence, too.

Beauty, like any other value, can be used for good or ill. This is what David Hume, the 18th century philosopher meant when he wrote that indulgences in luxury "are only vices when they are pursued at the expense of some virtue, as liberality or charity."

But our cultural obsession with beauty and looks has risks. Consider the case of Samantha Robichaud, who was hired to work at McDonald's in Northport, Ala., with aspirations to move up in management. She knew everything depended on learning the different necessary skills. After months of grilling Big Macs in the back kitchen, she asked for a position serving them at the front counter. Management refused. Continued...