The U.S. economy may be in a slump, but executives at the four major television networks are feeling upbeat. That's because they've just set a record -- $ 5.6 billion in advance sales for commercials in the next TV season

TV commercials are more lucrative than ever, but they wore out their welcome for many viewers long ago. Even Mr. Advertising himself, the famed ad wizard David Ogilvy, confessed in a 1963 memoir that he was ''angered to the point of violence'' by commercials intruding on TV programs.

''As a practitioner, I know that television is the most potent advertising medium ever devised, and I make most of my living from it,'' Ogilvy wrote. ''But, as a private person, I would gladly pay for the privilege of watching it without commercial interruption.''

That's supposed to be possible on PBS, also known as ''public'' television. But the plugs for program funders have been getting longer and flashier. And some PBS affiliates are now planning to air 30-second ''enhanced underwriter credits'' -- a euphemism for commercials.

The renowned historian Arnold Toynbee declared several decades ago that ''the destiny of our Western civilization turns on the issue of our struggle with all that Madison Avenue stands for.'' Toynbee might have been exaggerating, but the fact remains that ads are rarely condemned in the media outlets they're subsidizing.

Ogilvy was candid when he wrote, ''It strikes me as bad manners for a magazine to accept one of my advertisements and then attack it editorially -- like inviting a man to dinner and then spitting in his eye.'' In broadcasting, even more than in print, the ads paying the piper seem to be above criticism.

The wider its reach, the more that advertising melds into the prevailing scenery. We take ads for granted -- and sometimes we look at them fondly. With so much care and money lavished on TV commercials, they're sometimes far more creative than the programs they sponsor.

But modern TV commercials are a slick version of an age-old advertising quest -- to suck us into an unreal world of fabrication and mesmerizing artifice. As one observer put it back in 1924, ''Advertising may be described as the science of arresting human intelligence long enough to get money from it.''

When television was in its infancy four decades ago, the sociologist C. Wright Mills challenged the notion that people were just getting the commercial messages they wanted: ''Consumers are trained to 'want' that to which they are most continually exposed. Wants do not originate in some vague realms of the consumer's personality; they are formed by an elaborate apparatus of jingle and fashion, of persuasion and fraud.''

Meanwhile, Vance Packard raised a key question: ''By encouraging people constantly to pursue the emblems of success, and by causing them to equate possessions with status, what are we doing to their emotions and their sense of values?''

Here's one answer to that question: The daily advertising barrage deepens feelings of inadequacy, making us more receptive to the quick fixes offered by commercials.

As author Felix Greene wrote in 1970: ''Advertising is nothing more than a technique to keep people in a state of perpetual dissatisfaction with what they possess and in a permanent state of itchy acquisitiveness.''

Now, of course, hucksters are exploring the frontiers of high-tech. The Internet beckons, and America's advertising industry is accelerating onto the information superhighway.

For years, the Internet was almost commercial-free -- a forum for direct, decentralized communication among scholars, scientists and just plain folks. But, in the last year, the tacit taboo against ads in cyberspace has been broken.

Initial on-line advertising by such companies as Volvo, Hyatt Regency, MasterCard, Ragu, J.C. Penney Co. and Reebok is clearly the harbinger of a much bigger corporate selling blitz on the Internet.

For now, Internet ads are fairly limited and experimental. Yet, we should remember that advertising started out as an oddity on television, too.

The first TV commercial was probably on July 1, 1941, during a Dodgers-Phillies baseball game on New York station WNBT. The ad, for Bulova watches, aired at a cost of $ 9.

Fifty-four years later, the network execs at ABC, CBS, NBC and Fox are celebrating their slices of a $ 5.6 billion advertising pie. They call this progress. Many viewers might call it something else.