Over 400,000 people visited Farnam Street last month to learn how to make better decisions, create new ideas, and avoid stupid errors. With more than 100,000 subscribers to our popular weekly digest, we've become an online intellectual hub. To learn more about we what do, start here.

The Psychology of Persuasion

Robert Cialdini: The Psychology of Persuasion

I get a lot of emails from people asking me about the psychology of persuasion. Learning about the ways people (honestly and dishonestly) influence you is one of the best things to learn early in life.

But it’s never too late.

The go to book on the psychology of persuasion is Robert Cialdini’s Influence. Cialdini has spent a lifetime researching the psychology of compliance.

The book highlights six principles of persuasion, which most commonly and effectively are used by compliance practitioners.

We all employ them and fall victim to them, to some degree, in our daily interactions with neighbors, friends, lovers, and offspring. But the compliance practitioners have much more than the vague and amateurish understanding of what works than the rest of us have. … It is odd that despite their current widespread use and looming future importance, most of us know very little about our automatic behavior patterns . Perhaps that is so precisely because of the mechanistic, unthinking manner in which they occur. Whatever the reason, it is vital that we clearly recognize one of their properties: They make us terribly vulnerable to anyone who does know how they work.

These principles work via near automatic response – a “nearly mechanical process by which the power within these weapons can be activated, and the consequent exploitability of this power by anyone who knows how to trigger them.”

The Psychology of Persuasion

1. Reciprocation
This principle suggests people will be nice if you are. Therefore, if you do something first, by giving them something or doing something nice for them, it is more likely to come back to you. The key is to go first. And, at least in this case, size doesn’t matter. Something as small as a pen has been shown to influence people well beyond its monetary value.

Reciprocation is the basis of cashing in points, calling in a favor, owing other people one, etc.

The reason it works so well is that you have two choices, you either act in a socially approved way by giving in to a request or decline and face (perceived or real) shame. And we want to say yes because this is a way to avoid confrontation.

Reciprocation also works on multiple levels. We are more likely to trust someone who trusts us. We share secrets with people who share secrets with us.

One way to resist this is to refuse the initial favor or gift. Once you accept, it becomes a lot harder.

2. Consistency

Once we have made a choice or taken a stand, we will encounter personal and interpersonal pressures to behave consistently with that commitment.

It’s easier to get people to comply with requests that they see as consistent with what they’ve already said (especially in your presence.) This is the basis for one of the best interview hacks, I’ve ever seen. If you ask people to state their priorities and goals and then align your proposals with that in mind you make it harder for people to say no.

If you start to see yourself as a devil’s advocate for example, you will reinforce that idea by acting like a devil’s advocate.

Consistency is also the basis for the Ikea Effect and why a little pain makes something more attractive.

Say less at work and you’ll be more flexible when things change. Also examine why you want to comply and if things have changed. And keep a decision journal so you can see how often you’re wrong — there is no point holding on to bad ideas.

Once you’ve got a man’s self-image where you want it, he should comply naturally with a whole range of your requests that are consistent with this new view of himself.

3. Social proof

we…use the actions of others to decide on proper behavior for ourselves.

Ever wonder why TV shows use laugh tracks. It’s so you know when to laugh. I’ll let you sit on that one for a minute.

People will more likely say yes when they see other people doing it too. This is amplified in situations of uncertainty, where we look to others for cues on what we should do. This can be dangerous. If you are in an emergency, you might look around you for clues on what to do and how to act. Others, of course, might do the same thing. This is why, in an emergency, you need to give explicit instructions. You should always point to someone in a crowd, and say, you call 911. Point to another person and ask them to do something.

Cialdini writes:

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.

Consider walking into a restaurant in a foreign city. You’re starving and have no idea “what’s good” here. Luckily, there happens to be a section of the menu labelled “most popular dishes,” and that’s exactly what you’re likely to order.

Social poof is not all bad. It’s one of the main ways we learn in life. I’ve written extensively on this one before.

4. Liking
You prefer to comply with requests from people you like more than from people you don’t like. Go figure. One way people exploit this is to find ways to make themselves like you. Do you like golf? Me too. Do you like football? Me too. Although often these are genuine, sometimes they’re not. One way to get people to like you is to establish quick rapport.

This is the basis for tupperware parties. Who can say no to a good friend?

You also like people more if they like you. This is why Joe Girard, the world’s “greatest car salesman,” sends every customer a holiday card with the message “I like you.” And you know what, it works. People go back to him.

Oh, and by the way, I like you.

5. Authority
This relates to our tendency to be persuaded by authority figures, that is people who demonstrate knowledge, confidence, and credibility on the topic. Something as simple as informing your audience of your credentials before you speak, for example, increases the odds you will persuade the audience. Beware of those wearing uniforms or engineering rings as those are rather overt signs of authority.

We’re taught from a young age to listen to those in charge. And most times this works out ok but sometimes it doesn’t.

Consider this, the co-pilot is never supposed to let the plane crash no matter what, even in a simulator. The pilot, however, is the authority figure. So in simulators they’ve had the pilot do things that are so obviously wrong that an idiot would know that what he’s doing would lead to a crash. But the co-pilot just sits there because the pilot is the authority figure and a meaningful percentage of the time the plane crashes.

6. Scarcity

It is easy enough to feel properly warned against scarcity pressures, but it is substantially more difficult to act on that warning.

We all want something other people don’t or can’t have. If you offer people something rare or scarce, they are more likely to want it.

I just bought a book off amazon and interestingly on the page they said “Only 2 left in stock.” That’s scarcity. I better order now, or I might have to wait. And I don’t know about you but I really don’t want to miss out.

* * *

If you haven’t already I suggest you pick up a copy of Influence.