COLUMN ONE : How They Get You to Do That : Pitches are unending, whether from panhandlers or politicians or sales professionals. As the high (or low) art of persuasion is perfected, the public is ever more vulnerable.

The woman in the supermarket in a white coat tenders a free sample of “lite” cheese. A car salesman suggests that prices won’t stay low for long. Even a penny will help, pleads the door-to-door solicitor. Sale ends Sunday! Will work for food.

The average American exists amid a perpetual torrent of propaganda. Everyone, it sometimes seems, is trying to make up someone else’s mind. If it isn’t an athletic shoe company, it’s a politician, a panhandler, a pitchman, a boss, a billboard company, a spouse.

The weapons of influence they are wielding are more sophisticated than ever, researchers say. And they are aimed at a vulnerable target--people with less and less time to consider increasingly complex issues.

As a result, some experts in the field have begun warning the public, tipping people off to precisely how “the art of compliance” works. Some critics have taken to arguing for new government controls on one pervasive form of persuasion--political advertising.

The persuasion problem is “the essential dilemma of modern democracy,” argue social psychologists Anthony Pratkanis and Elliot Aronson, the authors of “Age of Propaganda: The Everyday Use and Abuse of Persuasion,” published last year.

As the two psychologists see it, American society values free speech and public discussion, but people no longer have the time or inclination to pay attention. Mindless propaganda flourishes, they say; thoughtful persuasion fades away.

The problem stems from what Pratkanis and Aronson call our “message-dense environment.” The average television viewer sees nearly 38,000 commercials a year, they say. The average home receives 216 pieces of junk mail annually and a call a week from telemarketing firms.

Bumper stickers, billboards and posters litter the public consciousness. Athletic events and jazz festivals carry corporate labels. As direct selling proliferates, workers patrol their offices during lunch breaks, peddling chocolate and Tupperware to friends.

Meanwhile, information of other sorts multiplies exponentially. Technology serves up ever-increasing quantities of data on every imaginable subject, from home security to health. With more and more information available, people have less and less time to digest it.

“It’s becoming harder and harder to think in a considered way about anything,” said Robert Cialdini, a persuasion researcher at Arizona State University in Tempe. “. . . More and more, we are going to be deciding on the basis of less and less information.”

Persuasion is a democratic society’s chosen method for decision-making and dispute-resolution. But the flood of persuasive messages in recent years has changed the nature of persuasion. Lengthy arguments have been supplanted by slogans and logos. In a world teeming with propaganda, those in the business of influencing others put a premium on effective shortcuts.

Most people, psychologists say, are easily seduced by such shortcuts. Humans are “cognitive misers,” always looking to conserve attention and mental energy--which leaves them at the mercy of anyone who has figured out which shortcuts work.

The task of figuring out shortcuts has been embraced by advertising agencies, market researchers and millions of salespeople. The public, meanwhile, remains in the dark, ignorant of even the simplest principles of social influence.

As a result, lay people underestimate their susceptibility to persuasion, psychologists say. They imagine their actions are dictated simply by personal preferences. Unaware of the techniques being used against them, they are often unwittingly outgunned.

As Cialdini tells it, the most powerful tactics work like jujitsu: They draw their strength from deep-seated, unconscious psychological rules. The clever “compliance professional” deliberately triggers these “hidden stores of influence” to elicit a predictable response.

One such rule, for example, is that people are more likely to comply with a request if a reason--no matter how silly--is given. To prove that point, one researcher tested different ways of asking people in line at a copying machine to let her cut the line.

When the researcher asked simply, “Excuse me, I have five pages. May I use the Xerox machine?” only 60% of those asked complied. But when she added nothing more than, “because I have to make some copies,” nearly everyone agreed.

The simple addition of “because” unleashed an automatic response, even though “because” was followed by an irrelevant reason, Cialdini said. By asking the favor in that way, the researcher dramatically increased the likelihood of getting what she wanted.

Cialdini and others say much of human behavior is mechanical. Automatic responses are efficient when time and attention are short. For that reason, many techniques of persuasion are designed and tested for their ability to trigger those automatic responses.

“These appeals persuade not through the give and take of argument and debate,” Pratkanis and Aronson have written. “. . . They often appeal to our deepest fears and most irrational hopes, while they make use of our most simplistic beliefs.”

Life insurance agents use fear to sell policies, Pratkanis and Aronson say. Parents use fear to convince their children to come home on time. Political leaders use fear to build support for going to war--for example, comparing a foreign leader to Adolf Hitler.

As many researchers see it, people respond to persuasion in one of two ways: If an issue they care about is involved, they may pay close attention to the arguments; if they don’t care, they pay less attention and are more likely to be influenced by simple cues.

Their level of attention depends on motivation and the time available. As David Boninger, a UCLA psychologist puts it, “If you don’t have the (time) or motivation, or both, you will pay attention to more peripheral cues, like how nice somebody looks.”

Cialdini, a dapper man with a flat, Midwestern accent, describes himself as an inveterate sucker. From an early age, he said recently, he had wondered what made him say yes in many cases when the answer, had he thought about it, should have been no.

So in the early 1980s, he became “a spy in the wars of influence.” He took a sabbatical and, over a three-year period, enrolled in dozens of sales training programs, learning firsthand the tricks of selling insurance, cars, vacuum cleaners, encyclopedias and more.

He learned how to sell portrait photography over the telephone. He took a job as a busboy in a restaurant, observing the waiters. He worked in fund raising, advertising and public relations. And he interviewed cult recruiters and members of bunco squads.

By the time it was over, Cialdini had witnessed hundreds of tactics. But he found that the most effective ones were rooted in six principles. Most are not new; but they are being used today with greater sophistication on people whose fast-paced lifestyle has lowered their defenses.

* Reciprocity: People have been trained to believe that a favor must be repaid in kind, even if the original favor was not requested. The cultural pressure to return a favor is so intense that people go along rather than suffer the feeling of being indebted.

Politicians have learned that favors are repaid with votes. Stores offer free samples--not just to show off a product. Charity organizations ship personalized address labels to potential contributors. Others accost pedestrians, planting paper flowers in their lapels.

* Commitment and consistency: People tend to feel they should be consistent--even when it no longer makes sense. While consistency is easy, comfortable and generally advantageous, Cialdini says, “mindless consistency” can be exploited.

Take the “foot in the door technique.” One person gets another to agree to a small commitment, like a down payment or signing a petition. Having done so, studies show that it becomes much easier to get the person to comply with a much larger request.

Another example Cialdini cites is the “low-ball tactic” in car sales. Offered a low price for a car, the potential customer agrees. Then at the last minute, the sales manager finds a supposed error. The price is increased. But customers tend to go along nevertheless.

* Social validation: People often decide what is correct based on what other people think. Studies show that is true for behavior. Hence, sitcom laugh tracks, tip jars “salted” with a bartender’s cash, long lines outside nightclubs, testimonials and man on the street ads.

Tapping the power of social validation is especially effective under certain conditions: When people are in doubt, they will look to others as a guide; and when they view those others as similar to themselves, they are more likely to follow their lead.

* Liking: People prefer to comply with requests from people they know and like. Charities recruit people to canvass their friends and neighbors. Colleges get alumni to raise money from classmates. Sales training programs include grooming tips.

According to Cialdini, liking can be based on any of a number of factors. Good-looking people tend to be credited with traits like talent and intelligence. People also tend to like people who are similar to themselves in personality, background and lifestyle.

* Authority: People defer to authority. Society trains them to do so; and in many situations, it is beneficial. Unfortunately, obedience is often automatic, leaving people vulnerable to exploitation by compliance professionals, Cialdini says.

As an example, he cites the famous ad campaign that capitalized on actor Robert Young’s role as Dr. Marcus Welby Jr. to tout the alleged health benefits of Sanka decaffeinated coffee.

An authority, according to Cialdini, need not be a true authority. The trappings of authority may suffice. Con artists have long recognized the persuasive power of titles like doctor or judge, fancy business suits and expensive cars.

* Scarcity: Products and opportunities seem more valuable when the supply is limited.

As a result, professional persuaders emphasize that “supplies are limited.” Sales end Sunday and movies have limited engagements--diverting attention from whether the item is desirable to the threat of losing the chance to experience it at all.

The use of influence, Cialdini says, is ubiquitous.

Take the classic appeal by a child to a parent’s sense of consistency: “But you said. . . .” And the parent’s resort to authority: “Because I said so.” In addition, nearly everyone invokes the opinions of like-minded others--for social validation--in vying to win a point.

One area in which persuasive tactics are especially controversial is political advertising--particularly negative advertising. Alarmed that attack ads might be alienating voters, some critics have begun calling for stricter limits on political ads.

In Washington, legislation pending in Congress would, among other things, force candidates to identify themselves at the end of their commercials. In that way, they might be forced to take responsibility for the ads’ contents and be unable to hide behind campaign committees.

“In general, people accept the notion that for the sale of products at least, there are socially accepted norms of advertising,” said Lloyd Morrisett, president of the Markle Foundation, which supports research in communications and information technology.

“But when those same techniques are applied to the political process--where we are not judging a product but a person, and where there is ample room for distortion of the record or falsification in some cases--there begins to be more concern,” he said.

On an individual level, some psychologists offer tips for self-protection.

* Pay attention to your emotions, says Pratkanis, an associate professor of psychology at UC Santa Cruz: “If you start to feel guilty or patriotic, try to figure out why.” In consumer transactions, beware of feelings of inferiority and the sense that you don’t measure up unless you have a certain product.

* Be on the lookout for automatic responses, Cialdini says. Beware foolish consistency. Check other people’s responses against objective facts. Be skeptical of authority, and look out for unwarranted liking for any “compliance professionals.”

Since the publication of his most recent book, “Influence: The New Psychology of Modern Persuasion,” Cialdini has begun researching a new book on ethical uses of influence in business--addressing, among other things, how to instruct salespeople and other “influence agents” to use persuasion in ways that help, rather than hurt, society.

“If influence agents don’t police themselves, society will have to step in to regulate . . . the way information is presented in commercial and political settings,” Cialdini said. “And that’s a can of worms that I don’t think anybody wants to get into.”