Book Notes: Influence: The Psychology of Persuasion

Book Notes: Influence: The Psychology of Persuasion

Book Notes: Influence: The Psychology of Persuasion

“Influence” by Dr. Robert B. Cialdini explains the psychology of why people are influenced and how to apply the findings to your own life.

I have always been interested in the fields of behavioral economics, evolutionary psychology and game theory and found that the learnings from this book can be leveraged in each of the fields. The power of studying Cialdini’s findings is to bring these techniques up into consciousness, not to learn how to trick other people into compliance, but to learn to defend ourselves against unthinking compliance in our own lives.

The 6 main principles explored in this book:
Commitment & Consistency
Social Proof


Costco Samples

Costco Samples

This rule states that people feel indebted to those who do something for them or give them a gift.

If someone does or gives something of value to you, you feel obligated return the value to them.
At the farmer’s market, do you ever take a “free sample” then feel the urge to buy the product to pay the vendor back? That urge is an example of this concept.

Application for Marketers:
The reciprocation principle explains why free samples can be so effective. People who receive a free, unexpected gift are more likely to listen to a product’s features, donate to a cause, or tip a waitress more money. The gifts do not have to be expensive or even material; information and favors can work.


commitment and consistencyThis principle states that people do not like to back out of deals that they have committed to. We’re more likely to do something after we’ve agreed to it verbally or in writing. People strive to follow pre-existing attitudes, values and actions and to remain consistent in their commitments.

People stay married, even though divorce may be the best option, because you’ve made a public commitment “til death do us part”.

Application for marketers:
People want to be consistent to their word. Getting customers or team members to publicly commit to an action makes them more likely to follow through with their commitment.


orange enzo ferrariThis principle states when people are uncertain about their actions, they tend to look to others around them to guide their decisions and actions. Specifically, they will be more likely to do what everyone else is doing.

For example:
You’re at a bar and your group order martinis, so you do the same.
You start buying the clothes that your friends or coworkers wear.
TV comedies play people laughing in the background to increase the chances you will laugh.

Application for marketers:
People will more likely purchase a product or service that showcases testimonials from satisfied customers who are similar to them. Use testimonials or showcase stories of others enjoying your product or service.


attractive sales peopleThis principle states that people have a preference to say ‘yes’ to those they know and like. Even something as ‘random’ as having the same name as your prospects can increase your chances of influencing the other person.

Factors that cause one person to like another:
A) Physical Attractiveness
B) Similarity
C) Compliments
D) Contact
E) Cooperation
F) Conditioning & Association

Pharmaceutical sales industries tend to higher attractive female doctors to products in the predominantly male physician industry.

Application for marketers:
Understanding the other person to convey similarities increases the chances of influence. Sales people could improve their chances of making a sale by becoming more knowledgeable about their prospects’ existing preferences.


firemanPeople respond to authority by complying to what the perceived authority tells them. The perception of being an expert creates the ability to influence. Business titles, impressive clothing, and even driving an expensive, high-performing automobile are proven factors in lending credibility to any individual.

Professional Titles: PhD, Esq, MBA, etc.
You’re more likely to purchase a car from a person in a suit vs. board shorts and flip flops.
You will follow what your child’s teacher recommends.

Application for marketers:
People with perceived authority are given automatic value in their field. Know the authorities in your industry and leverage their influence by incorporating testimonials from legitimate, recognized authorities to help influence.


limited time offerThis principle states that the less there is of something, the more valuable it is. The more rare and uncommon a thing, the more people want it. Ciadini says: “…we know that the things that are difficult to possess are typically better than those that are easy to possess, we can often use an item’s availability to help us quickly and correctly decide on its quality.”

Limited time offers – A certain product is in short supply that cannot be guaranteed to last long.
Exclusive deadline offers – and other exclusive clothing sites limit sales to purchase windows of opportunity increasing peoples emotional purchases.

Application for marketers:
People have a tendency to be more sensitive to possible losses more than to possible gains. Include the emphasis for the potential for a wasted opportunity in marketing campaigns. Emphasize the differentiation factors of your product to show how it is rare compared to other products.

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