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Influence by Robert B. Cialdini Summary | Free Audiobook

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free summary of Influence by Robert B. Cialdini


Did you buy something that you didn’t need again? Maybe a lava lamp that was on discount or two bottles of shampoo instead of just one because the sales clerk talked you into it? Did you donate money to a suspicious stranger just because they accosted you on the street? Or maybe you were persuaded to pay for a whole year gym membership that you didn’t really want? If the answer is yes, then you were the victim of compliance professionals: people who are trained to push the buttons that will make people do certain things and comply with their requests.

Well, the good news is that the author of the book, Robert B. Cialdini, knows this phenomenon all too well. He admits that he felt vulnerable and easy to trick and manipulate on many occasions. As a result, he dedicated his entire career to analyzing and questioning the ways in which people comply with other people’s requests. He has conducted numerous experiments on this topic and he managed to gather important data by interviewing compliance professionals and by watching them work. 


A well-known principle of human behavior says that when we ask someone to do us a favor, we will be more successful if we provide a reason. People simply like to have reasons for what they do.

Harvard social psychologist, Ellen Langer demonstrated this unsurprising fact by asking a small favor of people waiting in line to use a library copying machine:

“Excuse me, I have five pages. May I use the Xerox machine because I’m in a rush?”

The effectiveness of this request-plus-reason was nearly total: Ninety-four percent of those asked let her skip ahead of them in line. Compare this success rate to the results when she made the request only: 

“Excuse me. I have five pages. May I use the Xerox machine?”

Under those circumstances, only 60 percent of those asked complied. At first glance, it seems the crucial difference between the two requests was the additional information provided by the words “because I’m in a rush.”

But the third type of request tried by Langer showed that this was not the case. It seems that it was not the whole series of words, but the first one, “because,” that made the difference. Instead of including a real reason for compliance, Langer’s third type of request used the word “because” and then, adding nothing new, merely restated the obvious:

“Excuse me, I have five pages. May I use the Xerox machine because I have to make some copies?”

The result was that once again, nearly all (93 percent) agreed, even though no real reason, no new information, was added to justify their compliance.

There is a group of people who know very well where the weapons of automatic influence lie and who employ them regularly and expertly to get what they want. They go from social encounter to social encounter requesting others to comply with their wishes. Their frequency of success is dazzling. The secret of their effectiveness lies in the way they structure their requests, the way they arm themselves with one or another of the weapons of influence that exist within the social environment. To do this may take no more than one correctly chosen word that engages a strong psychological principle and sets an automatic behavior tape rolling within us. And trust the human exploiters to learn quickly exactly how to profit from our tendency to respond mechanically according to these principles.

This book will teach you the most effective persuasion techniques employed by these compliance professionals and about the six fundamental principles of manipulation. After reading our summary, you will be able to use these techniques to your advantage and to defend yourself from deceit. 

The Contrast Principle

The contrast principle is well established in the field of Psychophysics and applies to all sorts of perceptions besides weight. If we are talking to a beautiful woman at a cocktail party and are then joined by an unattractive one, the second woman will strike us as less attractive than she actually is.

The great advantage of this principle is not only that it works but also that it is virtually undetectable. Those who employ it can cash in on its influence without any appearance of having structured the situation in their favor.


Retail clothiers are a good example. Suppose a man enters a fashionable men’s store and says that he wants to buy a three-piece suit and a sweater. If you were the salesperson, which would you show him first to make him likely to spend the most money? Clothing stores instruct their sales personnel to sell the costly item first. Common sense might suggest the reverse: If a man has just spent a lot of money to purchase a suit, he may be reluctant to spend very much more on the purchase of a sweater. But the clothiers know better. They behave in accordance with what the contrast principle would suggest: Sell the suit first, because when it comes time to look at sweaters, even expensive ones, their prices will not seem as high in comparison. A man might balk at the idea of spending $95 for a sweater, but if he has just bought a $495 suit, a $95 sweater does not seem excessive.

The 6 Principles of Persuasion

The 1st Weapon of Persuasion: RECIPROCITY

Simply put, people are obliged to give back to others the form of a behavior, gift, or service that they have received first.

If a friend invites you to their party, there’s an obligation for you to invite them to a future party you are hosting. If a colleague does you a favor, then you owe that colleague a favor. And in the context of a social obligation, people are more likely to say yes to those who they owe.

The Sample Tactic

A different version of the free-sample tactic is used by the Amway Corporation, a rapid-growth company that manufactures and distributes household and personal-care products in a vast national network of door-to-door neighborhood sales. The company, which has grown from a basement-run operation a few years ago to a one-and-a-half-billion-dollar-yearly-sales business, makes use of the free sample in a device called the BUG.

The BUG consists of a collection of Amway products—bottles of furniture polish, detergent, or shampoo, spray containers of deodorizers, insect killers, or window cleaners—carried to the customer’s home in a specially designed tray or just a polyethylene bag. The confidential Amway Career Manual then instructs the salesperson to leave the BUG with the customer “for 24, 48, or 72 hours, at no cost or obligation to her. Just tell her you would like her to try the products… That’s an offer no one can refuse.”

At the end of the trial period, the Amway representative returns and picks up orders for those of the products the customer wishes to purchase. Since few customers use up the entire contents of even one of the product containers in such a short time, the salesperson may then take the remaining product portions in the BUG to the next potential customer down the line or across the street and start the process again. Many Amway representatives have several BUGs circulating in their districts at one time.

Of course, by now, you and I know that the customer who has accepted and used the BUG products has been trapped into facing the influence of the reciprocity rule. Many such customers yield to a sense of obligation to order those of the salesperson’s products that they have tried and thereby partially consumed.

The 2nd Weapon of Persuasion: SCARCITY

Simply put, people want more of those things they can have less of. People seem to be more motivated by the thought of losing something than by the thought of gaining something of equal value.

When British Airways announced in 2003 that they would no longer be operating the twice daily London—New York Concorde flight because it had become uneconomical to run, sales the very next day took off.

Notice that nothing had changed about the Concorde itself. It certainly didn’t fly any faster, the service didn’t suddenly get better, and the airfare didn’t drop. It had simply become a scarce resource. And as a result, people wanted it more.

Pamphlets urging young women to check for breast cancer through self-examinations are significantly more successful if they state their case in terms of what stands to be lost (e.g., “You can lose several potential health benefits by failing to spend only five minutes each month doing breast self-examination”) rather than gained (e.g., “You can gain several potential health benefits by spending only five minutes each month doing breast self-examination”).

The realization that we value limited information allows us to apply the scarcity principle to realms beyond material commodities. The principle works for messages, communications, and knowledge, too. Taking this perspective, we can see that information may not have to be censored for us to value it more; it need only be scarce. According to the scarcity principle, then, we will find a piece of information more persuasive if we think we can’t get it elsewhere.

The 3rd Weapon of Persuasion: AUTHORITY

This is the idea that people follow the lead of credible, knowledgeable experts.

Physiotherapists, for example, are able to persuade more of their patients to comply with recommended exercise programs if they display their medical diplomas on the walls of their consulting rooms. People are more likely to give change for a parking meter to a complete stranger if that requester wears a uniform rather than casual clothes.

There are several kinds of symbols that can reliably trigger our compliance in the absence of the genuine substance of authority.

Con artists, for example, drape themselves with the titles, clothes, and trappings of authority.

They understand that when they are so equipped, their chances for compliance are greatly increased. Each of these three types of symbols of authority has its own story and is worth a separate look.


Titles are simultaneously the most difficult and the easiest symbols of authority to acquire. To earn one normally takes years of work and achievement. Yet it is possible for somebody who has put in none of this effort to adopt the mere label and receive a kind of automatic deference. As we have seen, TV-commercial actors and con artists do it successfully all the time.


The second kind of authority symbol that can trigger our mechanical compliance is clothing. Though more tangible than a title, the cloak of authority is every bit as fakable. Police bunco files bulge with records of con artists whose artistry includes the quick change. In chameleon style, they adopt the hospital white, priestly black, army green, or police blue that the situation requires for maximum advantage. Only too late do their victims realize that the garb of authority is hardly its guarantee.


Aside from its function in uniforms, clothing can symbolize a more generalized type of authority when it serves an ornamental purpose. Finely styled and expensive clothes carry an aura of status and position, as do trappings such as jewelry and cars. The last of these status symbols is particularly interesting in the United States, where “the American love affair with the automobile” gives it unusual significance.

The 4th Weapon of Persuasion: CONSISTENCY

It is easier to resist at the beginning than at the end.

—Leonardo da Vinci

We like to be consistent with the things we have previously said or done.

Like the other weapons of influence, this one lies deep within us, directing our actions with quiet power. It is, quite simply, our nearly obsessive desire to be (and to appear) consistent with what we have already done.

Once we have made a choice or taken a stand, we will encounter personal and interpersonal pressures to behave consistently with that commitment. Those pressures will cause us to respond in ways that justify our earlier decision.

Consistency is activated by looking for, and asking for, small initial commitments that can be made. In one famous set of studies, researchers found rather unsurprisingly that very few people would be willing to erect an unsightly wooden board on their front lawn to support a Drive Safely campaign in their neighborhood.

However, in a similar neighborhood close by, four times as many homeowners indicated that they would be willing to erect this unsightly billboard. Why? Because ten days previously, they had agreed to place a small postcard in the front window of their homes that signaled their support for a Drive Safely campaign. That small card was the initial commitment that led to a 400% increase in a much bigger but still consistent change.

How big toy companies increase their January-February sales

They start prior to Christmas with attractive TV ads for certain special toys. The kids, naturally, want what they see and extract Christmas promises for these items from their parents. Now here’s where the genius of the companies’ plan comes in: They undersupply the stores with the toys they’ve gotten the parents to promise. Most parents find those things sold out and are forced to substitute other toys of equal value. The toy manufacturers, of course, make a point of supplying the stores with plenty of these substitutes. Then, after Christmas, the companies start running the ads again for the other special toys. That juices up the kids to want those toys more than ever. They go running to their parents whining, ‘You promised, you promised,’ and the adults go trudging off to the store to live up dutifully to their words.”

Why do cold-callers ask this?

Have you noticed that callers asking you to contribute to some cause or another these days seem to begin things by inquiring about your current health and well-being?

“Hello, Mr./Ms. Targetperson,” they say. “How are you feeling this evening?” Or, “How are you doing today?” The caller’s intent with this sort of introduction is not merely to seem friendly and caring. It is to get you to respond—as you normally do to such polite, superficial inquiries—with a polite, superficial comment of your own: “Just fine” or “Real good” or “I’m doing great, thanks.” Once you have publicly stated that all is well, it becomes much easier for the solicitor to corner you into aiding those for whom all is not well: “I’m glad to hear that, because I’m calling to ask if you’d be willing to make a donation to help out the unfortunate victims of…”

The theory behind this tactic is that people who have just asserted that they are doing/feeling fine—even as a routine part of a sociable exchange—will consequently find it awkward to appear stingy in the context of their own admittedly favored circumstances.

The 5th Weapon of Persuasion: LIKING

People prefer to say yes to those that they like.

But what causes one person to like another? Persuasion science tells us that there are three important factors. We like people who are similar to us, we like people who pay us compliments, and we like people who cooperate with us towards mutual goals.

Physical Attractiveness

Although it is generally acknowledged that good-looking people have an advantage in social interaction, recent findings indicate that we may have sorely underestimated the size and reach of that advantage.

Research has shown that we automatically assign such favorable traits to good-looking individuals as talent, kindness, honesty, and intelligence. Furthermore, we make these judgments without being aware that physical attractiveness plays a role in the process

Experiments have demonstrated that attractive people are more likely to get help when in need and are more persuasive in changing the opinions of an audience. Here, too, both sexes respond in the same way.


But what if physical appearance is not much of an issue? After all, most people possess average looks. Are there other factors that can be used to produce liking? As both researchers and compliance professionals know, there are several, and one of the most influential is similarity.

We like people who are similar to us. This fact seems to hold true whether the similarity is in the area of opinions, personality traits, background, or lifestyle. Consequently, those who wish to be liked in order to increase our compliance can accomplish that purpose by appearing similar to us in any of a wide variety of ways.

Dressing the same is a good example. Another way requesters can manipulate similarity to increase liking and compliance is to claim that they have backgrounds and interests similar to ours.


We are phenomenal suckers for flattery. Although there are limits to our gullibility—especially when we can be sure that the flatterer is trying to manipulate us—we tend, as a rule, to believe praise and to like those who provide it, oftentimes when it is clearly false.

Power of Associations

Compliance professionals use associations to teach the lesson. They are incessantly trying to connect themselves or their products with the things we like. Did you ever wonder what all those good-looking models are doing standing around in the automobile ads? What the advertiser hopes they are doing is lending their positive traits—beauty and desirability—to the cars. The advertiser is betting that we will respond to the product in the same ways we respond to the attractive models merely associated with it.

The linking of celebrities to products is another way advertisers cash in on the association principle. Professional athletes are paid to connect themselves to things that can be directly relevant to their roles (sport shoes, tennis rackets, golf balls) or wholly irrelevant (soft drinks, popcorn poppers, pantyhose). The important thing for the advertiser is to establish the connection; it doesn’t have to be a logical one, just a positive one.

The 6th Weapon of Persuasion: CONSENSUS (SOCIAL PROOF)

Especially when they are uncertain, people will look to the actions and behaviors of others to determine their own.

Bartenders often “salt” their tip jars with a few dollar bills at the beginning of the evening to simulate tips left by prior customers and thereby to give the impression that tipping with folding money is proper barroom behavior. Church ushers sometimes salt collection baskets for the same reason and with the same positive effect on proceeds. Evangelical preachers are known to seed their audience with “ringers,” who are rehearsed to come forward at a specified time to give witness and donations.

Advertisers love to inform us when a product is the “fastest-growing” or “largest-selling” because they don’t have to convince us directly that the product is good, they need only say that many others think so, which seems proof enough. The producers of charity telethons devote inordinate amounts of time to the incessant listing of viewers who have already pledged contributions. The message being communicated to the holdouts is clear: “Look at all the people who have decided to give. It must be the correct thing to do.”

Since 95 percent of the people are imitators and only 5 percent initiators, people are persuaded more by the actions of others than by any proof we can offer.

When we are unsure of ourselves, when the situation is unclear or ambiguous, when uncertainty reigns, we are most likely to look to and accept the actions of others as correct.

In the process of examining the reactions of other people to resolve our uncertainty, however, we are likely to overlook a subtle but important fact. Those people are probably examining the social evidence, too. Especially in an ambiguous situation, the tendency for everyone to be looking to see what everyone else is doing can lead to a fascinating phenomenon called “pluralistic ignorance.” Pluralistic Ignorance means a state in which each person decides that since nobody is concerned, nothing is wrong. Meanwhile, the danger may be mounting to the point where a single individual, uninfluenced by the seeming calm of others, would react.”

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