Six Scientifically Proven Principles of Persuasion (VIDEO)

Don’t do what you think might be right, do what science tells you is right.

Whether in business, in communication or in any activity you might be involved in, understanding the psychology of why people say yes is of invaluable benefit. 

In Influence, Dr. Robert Cialdini revealed his evidence-based research on what moves people to change behaviour. According to the Journal of Marketing Research, “[Influence] is among the most important books ever written for marketers”. Above you find an animated video that summarises the book. The ideas in this article are mainly taken from that video. 

Dr. Cialdini’s research demonstrates that we don’t consider all the available information to guide our decision making. Rather, we use shortcuts. 
These shortcuts are the 6 universal principles of persuasion. 

1. Reciprocity 
2. Scarcity
3. Authority 
4. Consistency 
5. Liking 
6. Consensus 

“Influence is among the most important books ever written for marketers.”

— Journal of Marketing Research

(1) Reciprocity 

Idea: we feel obliged to give when we receive. If a colleague does you a favour, you are more likely to return the favour. 

Example: when you go to restaurants, you often get a small gift at the end of your meal—usually at the same time of the bill. A study conducted in several restaurants aimed to understand whether the giving of a mint had any influence over how much tip people would leave. Here are the findings:

• when waiters gave a mint, tips increased by 3%
• when they gave two mints, tips increased by 14% 
• interestingly, when waiters gave one mint, went away and then came back to the table saying “for you nice people here’s an extra mint”, tips increased by 23%. We feel obliged to give when we receive.   

Key to remember: be the first to give and give something that’s personalised and unexpected. 

(2) Scarcity 

Idea: people want more of those things they can have less of.

Example: when British Airways announced in 2003 they would no longer operate their twice-daily London-New York flight, the next day sales took off. Why? Easy, the flight became a scarse resource, so people wanted it more. 

Key to remember: it’s not enough to highlight the benefits of the products or services you are selling. You also need to make your prospective customers understand why your product is unique and what they lose if they don’t buy it. 

(3) Authority 

Idea: people follow credible experts.

Example: if a doctor shows his diploma in his studio, you are more likely to trust him. If a person asks you for money to park somewhere, you are more likely to give the money if he wears a uniform rather than casual clothes. 

Key to remember: it doesn’t have to be you telling your potential clients you are brilliant. You can find other people to do that for you. That’s exactly what many online services do: they use experts who have already embraced an idea to convince others to follow them. Here’s a screenshot of the NextDraft’s landing page. It’s not Dave Pell himself trying to convince you to subscribe to his newsletter—he lets the President of the Atlantic and the Executive Producer of the Daily Show to do that for him. 

(4) Consistency 

Idea: people like to be consistent with the things they have previously said or done.

Example: a study reduced missed appointments at health centres by 18% simply by asking the patients rather than the staff to write down appointment details on the future appointment card. 

Key to remember: the consistency principle is activated by asking for small initial commitments that can be made. Remember, those commitments have to be voluntary.

(5) Liking

Idea: people say yes to those they like. This is fairly intuitive, but science also tells us specific factors that make us like people. 

We like:

• people who are similar to us
• people who pay us compliments
• people who cooperate with us towards mutual goals

Example: in a series of negotiation studies carried out between MBA students of two business schools, a group were told “time is money, get straight down to business”. In this group around 55% were able to come to an agreement. 
A second group were told “before you begin negotiating, exchange some personal information with each other and identify similarities you have in common. Then, begin negotiating”. In this group, 90% of them were able to come to a successful agreement. 

Key to remember: before you start doing business (whether online or offline), look for areas of similarity you share with others and pay genuine compliments. 

(6) Consensus 

Idea: people look at the behaviour of others to determine their own, especially when in doubt.

Example: visit the Buffer blog and scroll down to the bottom. A message will pop up: “Join more than 2 million people who save time on social media with Buffer”. This technique is used by many websites—and it works. It's a social proof: if you know that more than 2 million people are already using a service, I bet you start thinking it must be a cool service.

Key to remember: instead of relying on your own ability to influence others, you can point to what many others are already doing.         

In this article we’ve looked at six scientifically validated principles of persuasion. By implementing these small, practical and costless changes to your activities, you’ll see a big difference in your own ability to make others say yes to your requests.