Cialdini’s 6 Principles of Influence & Persuasion

There is a new Robert Cialdini book out this week — Pre-Suasion: A Revolutionary Way to Influence and Persuade. I have it on my Kindle but have just started reading it. I’m sure I’ll have more to say when I finish it in the coming weeks.

The reason I’m so excited about this new effort is that his original book, Influence: The Psychology of Persuasion, is in my hall of fame for books on behavioral psychology. The first place I heard about it was a recommendation from Charlie Munger, which was good enough for me.

The book was written in 1984 and, according to Cialdini, didn’t sell well at all for 4-5 years until evidence-based decision making finally started to gain prominence. The book contains six chapters on the various ways that we humans are susceptible — in both helpful and harmful ways — to influence and persuasion. Here are all six along with some interesting research from the book:

1. Reciprocation. There was a university professor who sent out Christmas cards to perfect strangers. Amazingly, these strangers returned the favor as cards came pouring into his mailbox from these people he had never met or talked to in his life. And the majority never asked who he was. If you give people something — a free sample, an invitation, a pleasant experience, useful information, etc. — they will feel obligated to give you something in return.

Another example from the book:

During the 1992 presidential campaign, actress Sally Kellerman was asked why she was lending her name and efforts to the candidacy of Democratic hopeful Jerry Brown. Her reply: “Twenty years ago, I asked ten friends to help me move. He was the only one who showed up.”

2. Commitment and Consistency. Psychologists studied a large group of gamblers at a horse racing track. They found that just after placing a bet people are much more confident about their horse’s chances of winning than they were just before placing the bet. They act as if the prospects changed simply because they placed their faith and money in the horse. People have an almost obsessive desire to appear consistent with their actions so we tend to take a hard line based on prior decisions and work hard to justify those earlier choices.

However, this is not always a bad thing. It can be used for good:

Suppose you wanted to increase the number of people in your area who would agree to go door-to-door collecting donations for your favorite charity. You would be wise to study the approach taken by social psychologist Steven J. Sherman. He simply called a sample of Bloomington, Indiana residents as part of a survey he was taking and asked them to predict what they would say if asked to spend three hours collecting money for the American Cancer Society. Of course, not wanting to seem uncharitable to the survey taker or to themselves, many of these people said they would volunteer. The consequence of this sly commitment procedure was a 700 percent increase in volunteers.

3. Social Proof. I’ve always wondered why network comedies rely on a fake laugh track following all jokes, good or bad. It comes off as cheesy and overdone. It turns out experiments show that audiences laugh longer and more often when a laugh track is in place. They also rate the material as being funnier, which is even more effective for the worst jokes. (Luckily, the best comedies these days have now gotten rid of the laugh track.)

Social proof is the reason for this. We look to others to figure out what the correct behavior should be. We assume that more people doing something must mean it’s the right move. This is the reason for the herd mentality.

Here’s another good one from Cialdini on this:

At the height of the disco craze, certain discotheque owners manufactured a brand of visible social proof for their clubs’ quality by creating long waiting lines outside when there was plenty of room inside. 

4. Liking. In the 1980s, Joe Girard was named by the Guinness Book of World Records as the “greatest car salesman.” When asked for his simple formula for success he named two simple tactics. First, he offered a fair price. And second, he got people to like him. That’s it. An obvious truth is that most people prefer to say yes to someone they feel they know or like as a person.

There are a number of traits that draw people in — similarities, compliments, cooperation or contact. Another is physical attractiveness:

A study of the Canadian federal elections found that attractive candidates received more than two and a half times as many votes as unattractive candidates. Despite such evidence of favoritism toward handsome politicians, follow-up research demonstrated that voters did not realize their bias. In fact, 73 percent of Canadian voters surveyed denied in the strongest possible terms that their votes had been influenced by physical appearance; only 14 percent even allowed for the possibility of such influence.

In one study, good grooming of applicants in a simulated employment interview accounted for more favorable hiring decisions than did job qualifications — this, even though the interviewers claimed that appearance played a small role in their choices.

5. Authority. I used the following story from Influence in my own book:

There’s a funny story about a doctor who ordered ear drops to be administered in the right ear of a patient who was suffering from an ear infection. Doctors are notorious for poor handwriting skills and using shorthand notations. In this case, instead of completely writing out “right ear” on the prescription pad, the doctor abbreviated and instead wrote “R ear.” The nurse on duty received the prescription with the instructions from the doctor and promptly put the ear drops on the patient’s anus. She knew it was an ear infection so putting the ear drops on the patient’s rear end made absolutely no sense, but she never questioned the instructions because they came from a doctor. The patient went right along as well. No one bothered to question the misinterpreted instructions because they came from someone in a position of influence.

People tend to listen to those in a position of power whether it’s the right thing to do or not. We tend to take experts (or “experts”) at their word. People are very obedient, many times to their own detriment, simply because a person or group in a position of authority has told them to do or believe something.

6. Scarcity. Homeowners who are told how much money they could lose from poor insulation throughout their house are more likely to insulate their homes than those who are told how much they could save. Something will seem more valuable when its quantity is limited. People also tend to have a harder time dealing with the prospect of losing something than the prospect of gaining something (also known as loss aversion).

Here’s a good example of this:

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”).

Influence: The Psychology of Persuasion

And here’s the new book:
Pre-Suasion: A Revolutionary Way to Influence and Persuade

Here’s what I’ve been reading this week:


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