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  • Writer's pictureMark Walmsley

Influence by Robert Cialdini Summary

Updated: Mar 8, 2021

Influence Book Mockup

Influence explains in detail six fundamental principles of persuasion – reciprocation, commitment and consistency, social proof, liking, authority, and scarcity. You’ll also learn how to avoid them, and how to use them for ethical gain by understanding specific everyday examples and the underlying psychology behind each principle. Researched and presented by a world-renowned expert in the field. Key insights:

  1. Reciprocation is the tendency to do things for others who first do things for us – to agree to buy a product after having a small ‘free’ sample

  2. Commitment/consistency is the tendency to act in a manner consistent with prior commitments – to say yes to purchasing the car after ‘nominating’ which color and extras you’d be interested in

  3. Social proof is the tendency to like or purchase things based on others actions – which is why testimonials or ads stating ‘highest selling’ or ‘number 1’ are so persuasive

  4. We tend to buy more from people we like; and we tend to like attractive, funny, complimentary, people from our location who barrack for our ‘team’

  5. We respond positively to authority figures such as academics, professional people (dentists), or people in uniforms

  6. Perceived scarcity triggers our ‘fear of missing out’ instinct and encourages to take quick ill-thought-out action

  7. You can resist these six influence techniques by first understanding how they work and where they are routinely applied

  8. It is wise to assume most testimonials are fake, and most authority figures are just likeable actors

  9. Auctions are a deliberate attempt to create scarcity and trigger FOMO. So are websites with obviously fake ‘offer ends in 24 hours’ deals

  10. ‘Mere puff’ is the legal term describing a claim that the product is the world’s best; the courts don’t expect anyone to take such claims seriously, so neither should you

Book details

Full title: Influence: The Psychology of Persuasion, by Robert Cialdini PhD

Length: 336 pages, or 10 hours and 6 mins on Audible

Buy the book (USA): Amazon (book, Kindle, Audible)

Buy the book (AUS): Amazon (book, Kindle, Audible), Booktopia (book, eBook, audio-book)

Key insight 1: Biological responses – we are more animal than we think

Caldini introduces the topic by discussing how animals have instinctual responses to certain environmental events. A turnkey for example will care for her chicks that go ‘cheep-cheep’, but will ferociously attack a stuffed polecat nearby. Unless a research makes the puppet polecat go ‘cheep-cheep’ in which case the turkey will bring the polecat into her nest. This is called a fixed-action pattern and it applies to us humans as well.

Fixed-action patterns are the mental shortcuts and assumptions we use to simplify our lives. For example, we instinctively brake when we see the brake light illuminate on the car in front of us; or assume a crowd gathering in the mall is looking at something interesting. However, these fixed-action patterns are known to marketers, fund raisers, or politicians to get us to do something we wouldn’t normally do. Cialdini documented six principles of influence as follows.

1. Reciprocation. Folks generally feel obliged to return favors offered to them. This trait is embodied in all human cultures and is one of the human characteristics that allow us to live as a society. Compliance professionals can play on this trait by offering a small gift to potential customers knowing that the customer will feel obliged to reciprocate by purchasing a related product (e.g. in-store product sampling).

Another sales technique is to ask for an unreasonably large favor, and when refused, ask for a smaller favor. The victim here may agree to the small request in response to the perceived down-scaling of the original ask.

2. Commitment and Consistency. People have a general desire to appear consistent in their behavior. People generally also value consistency in others. Compliance professionals can exploit the desire to be consistent by having someone make an initial, often small, commitment, known as the ‘foot-in-the-door technique’. Additional small requests continue with the end result being a larger overall commitment from the victim.

Another technique is for compliance professionals get agreement on a small offer, only for the offer to be slowly changed in a way that is less favorable for the victim and more profitable for the proposer. This is known as the ‘escalation-of-commitment’ technique.

3. Social proof. People generally look to other people similar to themselves when making decisions. This is particularly noticeable in situations of uncertainty or ambiguity. This trait has led compliance professionals to provide fake information on what others are doing. Examples of this include a handsome dentist on TV telling you he uses brand XYZ toothpaste, paid professionals doing ‘infomercials’.

The canned laughter track played on TV sitcoms is also an example of this technique. Lastly, any product billed as the ‘fastest-growing’, ‘largest-selling’, or ‘highest-rated’ is appealing to the social proof technique because these attributes – if true – only arise from lots of other people buying the items.

4. Liking. People are more likely to agree to offers from people whom they like. And we tend to like:

  • attractive people – have you ever seen an unattractive TV product model?

  • funny people – notice how comedians or funny commercials are used

  • those who pay us compliments

  • those like ourselves – that is age, gender, identity, or education as appropriate

  • those who barrack for our team - either sporting, political, or other group as appropriate

  • or those from our location – either town, state, or nation as appropriate

Beware, you may often see combinations of the above to improve their likelihood of success.

5. Authority. People often react in an automated fashion to commands from authority and even to symbols of authority (e.g. academic degrees, uniforms or badges), even when their instincts suggest the commands should not be followed. The Milgram experiment in which test subjects were commanded by a ‘scientist’ to deliver what they thought to be near-fatal electronic shocks is one famous example of the strength of this technique.

6. Scarcity. People tend to want things as they become less available. This has led advertisers to promote goods as ‘limited availability’, or ‘short time only’. People instinctively understand supply and demand as market forces, so something that is becoming scarce relative to demand, will soon become more expensive. The approach can also apply to information. So called ‘exclusive offers’ or insider like information offers the opportunity to get onboard before everyone else; and in so doing beat the impending demand for the product.

Key insight 2: Life hacks to beat unwanted ‘influence’

In this section we’ll briefly explore a few hacks to beat the six influence principles noted above.

1. Reciprocation. One strategy is to automatically decline any first offers from strangers; however the dangers here should be obvious. First, you can come across as being rude; and second the offer may have been genuine. Instead, Cialdini suggests that you accept a desirable first offer in the knowledge that you may be obligated to return a similarly small favor in the future. However, if the first offer was nothing more than a trick to designed to trigger our acceptance of a larger request then the requester has voided the social contract and we are free of any obligations.

“As long as we perceive and define his action as a compliance device instead of a favor, he no longer has the reciprocation rule as an ally: The rule says that favors are to be met with favors; it does not require that tricks be met with favors.”

2. Commitment and Consistency. One strategy for avoiding this compliance technique involves listening to your stomach and then naming the technique. Confused? Cialdini observes that when you are getting played by this technique you’ll feel it as a sinking feeling in your stomach. He further notes that as a major bodily organ the stomach should be listened to as a cue that something is not right. More from Cialdini:

“The first sort of signal is easy to recognize. It occurs right in the pit of our stomachs when we realize we are trapped into complying with a request we know we don’t want to perform.”

The second step Cialdini notes is to call out the technique and tell the compliance professional that you acknowledge saying ‘no’ to their final/latest offer may be inconsistent with your prior statements, but the situation has changed and that, as they, say is that. From Cialdini:

“This tactic has become the perfect counterattack for me. Whenever my stomach tells me I would be a sucker to comply with a request merely because doing so would be consistent with some prior commitment I was tricked into, I relay that message to the requester. I don’t try to deny the importance of consistency; I just point out the absurdity of foolish consistency. Whether, in response, the requester shrinks away guiltily or retreats in bewilderment, I am content. I have won; an exploiter has lost.”

3. Social proof. Cialdini’s response to the use of social proof by compliance professions is for us to a) tune in more to the information stream to be alert to false social proof examples, and b) be prepared to disengage your ‘autopilot’ – that process in your brain that cues the fixed-action pattern response. From Cialdini:

“Because autopilots can be engaged and disengaged at will, we can cruise along trusting in the course steered by the principle of social proof until we recognize that a piece of inaccurate data is being used. Then we can take the controls, make the necessary correction for the misinformation, and reset the automatic pilot.
The transparency of the rigged social proof we get these days provides us with exactly the cue we need for knowing when to perform this simple maneuver. With no more cost than a bit of vigilance for plainly counterfeit social evidence, them, we can protect ourselves nicely.”

4. Liking. Cialdini’s strategy to avoid the liking principle is to focus on the effect rather than the process. Here he means to be observant to when we feel an undue affiliation with someone as evidence of this effect, rather than try to spot the technique in real time. Cialdini again:

“Our vigilance should be directed not toward the things that may produce undue liking for a compliance practitioner, but toward the fact that undue liking has been produced. The time to react protectively is when we feel ourselves liking the practitioner more than we should under the circumstances.”

5. Authority. The strategy to avoid falling to authority figures undue influence is to ask two questions. First, ask “Is this authority truly an expert?” With deliberate evaluation it may be that they are either not an expert, or not in the way they claim. Then ask the second question, “How truthful can we expect the expert to be here?” Recall the dentist in the TV advertisement mentioned about; he is an actor not a real dentist, and if he was a dentist he isn’t being very truthful as he’s paid to promote the product.

6. Scarcity. Cialdini has a two staged approach to avoiding scarcity as a sales tactic. First, recognize your growing anxiety at the prospect of ‘missing out’ on something as a cue to this technique. Then ask yourself whether having this product – the one subject to scarcity – will be better than having the next one that is available.

Key insight 3: Using reciprocation, commitment and consistency for personal gain

The study of influence isn’t all doom and gloom and working out how avoid salesman selling your unwanted stuff. It can also be turned to your advantage. Say you’re looking to trim down a little for summer, here’s how two of these principles can help.

Reciprocation. Ask a friend to go walking with you a few times. In time they’ll reciprocate by asking you to come walking with them. In time you’ll have a regular session happening.

Commitment. Make your exercise, diet, or weight loss goals public. Then, through this influence principle you’ll be incentivized to keep your commitments in order to avoid looking silly.

Consistency. Buy a gym membership, exercise outfit, or push-bike. Then through the consistency principle you’ll be incentivized to use them; otherwise you would have been inconsistent in purchasing them and not using them.

Other insights from Influence

4. Are any product testimonials real? If you think about the effort that a company goes into providing a testimonial – whether written, spoken, or on camera – can you assume any of them are real? Of course not; when you see a testimonial it is safe to assume it is fabricated with one purpose only…

5. Spotting ‘mere puff’. In 1892 a company was taken to court when they failed to pay £100 when their influenza prevention device failed to work – a promise made in their advertising. Their defense was to claim the statement was ‘mere puff’ and not meant to be taken seriously. They lost the case; but the principle that outlandish and untrue marketing claims can be legally made was establish.

6. An authority seeker may ‘argue’ against their interest. One technique for authority seekers is to subtly undermine themselves in the pursuit of a favorable outcome. Consider Avis’ “We’re number two, but we try harder”, or “L’Oréal, a bit more expensive and worth it.” The trick is to establish truth in a minor point so as to be more believable on the core argument.

7. Auctions as deliberate scarcity. The simple auction, whether for car, housing, or any item, is used by the seller to create scarcity in that there is presumably one item for sale, and more than one willing buyers. Ebay in the early days sold almost exclusively by quick action auctions as a means to pump up the sale price.

8. Is it really scarce? Another way around the scarcity tactic is to ask if the product in question is really scarce? Or more specifically, can more of these be easily provided to the customers. So the last house, last diamond ring, or last seat on the plane may not actually be the last one available.

9. Is time really running out? The tactic of limiting the time available to make a decision is very common on the internet and elsewhere. To avoid it just ask yourself if it make sense for the sale to be time limited? What’s the logic behind an online sale ending in 24 hours? You can reasonably suspect this ‘limited time offer’ happens at the end of every week, month, or quarter; or in extreme cases – is shown to every potential purchaser.

10. If nothing else – slow down. It should be obvious by now that marketers have quite the advantage when it comes to separating us from our hard earned money. If there is one thing we can do to put the odds back in our favor it is this – slow down. With very few exceptions anyone wanting to sell you something will take the time you need to make a good decision. If they won’t, then realize they don’t want you have time to think, and you probably don’t want their product. To quote Wiz Khalifa, “Never make permanent decisions on temporary feelings.”

Why you should read this book if you’re under 30

If you find it hard to say no to sales pitches, work in sales or marketing, or have an interest in the psychology of persuasion then this book is for you. You’ll learn to identify the six key influence tactics in real time across society, how to avoid falling foul of them, how to use them if that’s your job, and how to leverage them to motivate yourself if you need to. Since we can’t stop our automatic response to these principles when used against us, we need to understand how to defend against them, or leverage them to our advantage. An excellent book by the founding researcher in this field.

Relationship to other Eruditeable books

#3 – Atomic Habits. This book provides guidance on how to turn the influence principles you are using on yourself into permanent good habits.

#15 – 50 Etiquette Lessons. A good understanding of etiquette principles and norms may help you in identifying when compliance professionals are being unduly nice.

#16 – The Personal MBA. This book will provide a broader understanding of sales and marketing where some of the six influence techniques identified may be put to use.

#19 – Gifts Differing. This book will help you realize more about your personality, and how perceptive to these six influence techniques you are likely to be.

#23 – The Lean Startup. If you decide to start your own business you’ll no doubt need to design systems for marketing and selling products or services to customers. An understanding of these six influence principles will be helpful in the design and development of these systems.

Book resources

About the author

Robert Beno Cialdini (born 1945) received his Bachelor of Science degree from the University of Wisconsin - Milwaukee in June 1967. He then went on to Graduate studies in Social Psychology at the University of North Carolina and earned his Ph.D. in June 1970 and received Postgraduate training in Social Psychology at Columbia University. He has held Visiting Scholar Appointments at Ohio State University, the University of California, the Annenberg School of Communications, and the Graduate School of Business of Stanford University. Currently, Cialdini is Regents’ Professor Emeritus of Psychology and Marketing at Arizona State University.

He is best known for this book on persuasion and marketing; which was based on three "undercover" years applying for and training at used car dealerships, fund-raising organizations, and telemarketing firms to observe real-life situations of persuasion. The book has sold over three million copies and has been translated into thirty languages. It has been listed on the New York Times Best Seller list, and Fortune lists it in their "75 Smartest Business Books".

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