Table of Contents



About the Author

About the Technical Editor




Evil designs and their virtuous counterparts


Misplaced pride causes cognitive dissonance

Social proof: Using messages from friends to make it personal and emotional

Closure: The appeal of completeness and desire for order

Manipulating pride to change beliefs


Sloth: Is it worth the effort?


Deserving our rewards

Escalating commitment: foot-in-the-door, door-in-the-face

Invoking gluttony with scarcity and loss aversion


Avoiding anger

Embracing anger

Using anger safely in your products


Manufacturing envy through desire and aspiration

Status envy: demonstrating achievement and importance

Manufacturing and maintaining envy in your products


Creating lust: Using emotion to shape behavior

Controlling lust: Using desire to get a commitment

Lustful behavior


Learning from casinos: Luck, probability, and partial reinforcement schedules

Anchoring and arbitrary coherence

Evil by Design

Should you feel bad about deception?

Should you feel bad about using the principles in this book?

Be purposefully persuasive

The Persuasive Patterns Game









About the Technical Editor










To my wife, Mel, for putting up with me during the crunch times; and my dog, Sheila, for giving me the best excuse for taking breaks during those same crunch times.


Acquisitions Editor

Mary James

Senior Project Editor

Adaobi Obi Tulton

Technical Editor

Dan Lockton

Senior Production Editor

Kathleen Wisor

Copy Editor

Apostrophe Editing Services

Editorial Manager

Mary Beth Wakefield

Freelancer Editorial Manager

Rosemarie Graham

Associate Director of Marketing

David Mayhew

Marketing Manager

Ashley Zurcher

Business Manager

Amy Knies

Production Manager

Tim Tate

Vice President and Executive Group Publisher

Richard Swadley

Vice President and Executive Publisher

Neil Edde

Associate Executive Publisher

Jim Minatel

Project Coordinator, Cover

Katie Crocker


Maureen Forys, Happenstance Type-O-Rama


Nancy Carrasco


John Sleeva

Cover Image

Chris Nodder

Cover Designer

Ryan Sneed

Background Images

Ryan Sneed

About the Author

ChrisNodder is the founder of Chris Nodder Consulting LLC, an agile user experience consultancy that helps companies build products that their users will love.

Chris also runs the website, which gives lean and agile teams the tools they need to run their own user research; and he is a video author. He presents on user experience topics at international conferences.

Before starting his own consulting business, Chris gained invaluable experience working with some of the best companies in the industry. He was a director with Nielsen Norman Group, a premiere international user research company, for 5 years. He also worked for 7 years as a senior user researcher at Microsoft Corp.

He has a background in psychology and human-computer interaction.

About the Technical Editor

Dan Lockton specializes in design for behavior change—understanding and influencing the use of products and services for social and environmental benefit. For his Ph.D. Dan developed the Design with Intent Toolkit, a pattern library for designers working in this emerging field. He is a senior research associate at the Helen Hamlyn Centre for Design, Royal College of Art, London, and does consultancy through his company, Requisite Variety.


The User Experience Dream Team: Jakob Nielsen for giving me the opportunity to test out some of the ideas in this book as a Nielsen Norman Group conference keynote; Don Norman for suggesting the title of the book and writing a wonderful introduction; and the benign trickster Bruce “Tog” Tognazzini for his inspirational story-telling.

The people at Wiley: especially Mary James, who first suggested I turn these ideas into a book; Adaobi Obi Tulton for keeping me (somewhat) on track; and San Dee Phillips for making my tenses agree, my punctuation perfect, and my English American.

The indispensables: Dan Lockton not just for setting me straight with technical edits but also for providing some great examples and new directions; Scott Berkun for giving me insights into the craziness of ever deciding to write a book; all the anonymous online reviewers; and finally all the companies and individuals who unintentionally provided the examples used in this book.


Sloth, Pride, Envy, Greed, Lust, Anger, Gluttony. What? I’m supposed to design for these traits? As a human-centered designer, I should be repelled by the thought of designing for such a list. What was Chris Nodder thinking? What was his publisher thinking? This is evil, amplified.

Although, come to think of it, those seven deadly sins are human traits. Want to know how people really behave? Just read the law books. Start with one of the most famous set of laws of all, the Ten Commandments. Every one of those commandments is about something that people actually did, and then prohibiting it. All laws are intended to stop or otherwise control human behavior. So, if you want to understand real human behavior, just see what the laws try to stop. The list of seven deadly sins provides a nice, tidy statement of fundamental human behavior, fundamental in the sense that from each of the deadly sins, one can derive a large list of less deadly ones.

But why should design be based on evil? Simple: Starting with evil means starting with real human behavior. This doesn’t mean that the result is evil: It means that understanding what each sin represents adds to an understanding of people. And good design results from good understanding. This is Chris Nodder’s great insight: Human frailty provides a great learning experience, illustrative examples that teach fundamental principles. And just as all fundamental principles can be used for good or evil, Nodder’s principles can be used in either way.

There are obvious benefits to society in using the lessons learned from the sins to enhance design processes for the good of humankind. But there are also benefits to understanding how those who are less scrupulous than you or me use these same principles for nefarious purposes, defrauding people, or perhaps just causing them to buy things they do not need at a price they cannot afford. What possible benefits? The more the tactics are understood, the more readily they can be identified and resisted, fought against, and defeated.

Nodder has done a superb job of distilling and explaining. Fun to read, insightful to contemplate. Maybe he did too good a job—I am now far better equipped to do evil than I was before I read the book. But I’m also better equipped to notice when others apply these principles to me; and they do, many times a day, as I browse the Internet, click links, or wander the streets of my little town in the Philistine area called Silicon Valley; resisting temptations of greed, lust, and gluttony as I watch the natives feeding at outdoor cafes; buying at fancy glass-encased stores selling tantalizing electronic sin toys; passing the offices of venture capitalists along the way, with fancy, unimaginably expensive and powerful automobiles parked in front (in a city where the speed limit is 25 miles per hour, and it is rare to go even that fast). Which sins are on constant display? Every one of them.

The seven sins are all around us, easy to spot. But the designs that apply the underlying behavioral forces that underpin the sins are harder to discern. That’s why we need this book.

Thank you Chris for providing insight coupled with fun. Teaching deep insights into human behavior together with valuable guidelines and frameworks for applying them is a blessing—57 blessings, one for each design pattern that Nodder has derived from the seven sins. Learning from sins. Pleasure from sins. A wonderful combination.

So yes, buy the book. No, don’t download it for free: That would be sinful.

Don Norman

Nielsen Norman group

Author of Design of Everyday Things

Palo Alto, California


In Mark Twain’s classic book, The Adventures of Tom Sawyer, Sawyer convinces others to do his work for him by making the chore of painting a fence seem instead a desirable job. His friends beg to be involved.

Tom said to himself that it was not such a hollow world, after all. He had discovered a great law of human action, without knowing it—namely, that in order to make a man or a boy covet a thing, it is only necessary to make the thing difficult to attain.

Mark Twain, The Adventures of Tom Sawyer, 1876

Designers work hard to control the emotions and behaviors of their users. Truly great websites—good or evil—use specific techniques to get users to perform the desired task time and time again. Success in web design is most often measured in terms of how many users beg to be involved; creating, sharing, commenting, or purchasing.

Evil designs and their virtuous counterparts

Design is about persuasion. Marketers first codified many of these persuasive behaviors in the mid-1930s. It took until the turn of the century for economic researchers and psychologists to work out why people respond to these behaviors in the way they do. Now you can learn how to apply this knowledge in interaction design.

Sites capitalize on our weaknesses. Sometimes their intentions are good, but mainly they do this for “evil”—in other words to profit at our expense. The best sites manage to make us feel good at the same time.

Learning from the best

Controlling people’s behavior for financial gain is not a new concept. Casinos do it, politicians do it, and marketers do it. Here, we consider human foibles and the manner in which they can be exploited into the digital age: How do we influence behavior through the medium of software?

We will draw many examples from existing apps and websites. The creators of these products may have been unaware of the psychological underpinnings of their design decisions. Indeed, they may not have intended to be truly evil in their implementations. However, the end results are often wonderful advertisements for evil by design.

Like a good magic trick, the best examples are the ones where you don’t even realize that people are being manipulated until it’s pointed out to you. When you understand the reasons why users respond the way they do, you’ll appreciate even more how clever some of these “tricks” actually are and marvel at the beauty of some of the evil designs.

Defining evil design

We must differentiate between evil design and plain stupidity. Often, a lazy or ill-thought-out design can infuriate us. However, it takes a truly well-conceived evil design to make us come back for more.

Stupidity isn’t evil. People who create bad designs because they don’t know any better or because they are lazy aren’t being evil. Evil design must be intentional. In fact, as you’ll see in the various chapters, there is often a lot of planning involved in creating an evil design that truly works.

The idea behind evil design is that people enter willingly into the deal, even when the terms are exposed to them. Confidence tricksters are another group who control behavior for gain, but they take things a stage further than evil design by hiding the true outcome of the activity.

Stupidity is sloppily coded error messages that don’t explain what’s wrong, or how to fix it. Those dialog boxes are frustrating but benign. A con is software that promises to remove viruses but instead infects your computer. This is evil masquerading as good—and if users manage to see behind the mask, they will be dismayed. Evil design works on a different level, by convincing customers that the value proposition is in their best interest (financially or emotionally) and by persuading customers to participate even if they are aware of the imbalance in the outcome.

So evil design is that which creates purposefully designed interfaces that make users emotionally involved in doing something that benefits the designer more than them.

Human weakness: The seven deadly sins, and how sites leverage them

It seems only fitting to lay out the contents of this book according to the vices that sites exploit to attract and engage with users. Thus, the subsequent chapters group design techniques under the headings of the Seven Deadly Sins.

Throughout history, philosophers and religious scholars have categorized human weakness as a set of “sins.” The Seven Deadly (unforgivable) Sins are Pride, Sloth, Gluttony, Anger, Envy, Lust, and Greed. Each chapter in this book addresses one of these sins, pointing out the human characteristics that enable software designers to create persuasive interfaces that appeal to each weakness. Using examples from contemporary web design, you will be able to see how the sin is exploited both for good and for evil. Each characteristic is accompanied by design patterns that give you simple rules to apply these same techniques in your own work.

This book concludes with a discussion about ethics. Not the heart-wrenching moral dilemma of whether to use any of these evil-by-design patterns, but instead an acceptance that they are being used already today. Knowing how to recognize these patterns enables you to turn them to your advantage both as a consumer and as a designer of software and websites.


Humility makes men like angels; Pride turns angels into devils.

Saint Augustine

Pride isn’t the sin it used to be. In the 4th Century, Evagrius of Pontus claimed that pride was the primary sin among the seven, and the one from which all others stemmed. By the time of Thomas Aquinas in the 13th Century, it was seen in a more measured manner—some pride was acceptable, but a surfeit was still a sin. In the 21st century, with the advent of social media, it appears that we more often ask, “Have you no pride?” when confronted with yet more drunken party photos, as if pride is a positive attribute that arbitrates in matters of taste.

These days, the sense in which pride is bad is probably best summed up by the word hubris—arrogance, loss of touch with reality, overestimating one’s capabilities, thinking that you can do no wrong. In the Greek tragedies, hubris leads the hero to pick a fight with the gods and thus be punished with death for his insolence. These days, it’s called overextending your credit.

Of course, the aim in this book isn’t to bemoan the lack of humility in modern society but to see how sites leverage this human weakness.

Misplaced pride causes cognitive dissonance

Harold Camping, the owner of, has been wrong a couple of times in the past. He predicted that the world would end on May 21, 1988—then again on September 7, 1994, and subsequently on May 21, 2011, before settling for October 21, 2011. After the world steadfastly refused to stop turning on each of these dates, you’d think that Harold would call it quits and stop believing that the Rapture was imminent. You’d also think that the large number of his followers who sold or gave away all their possessions or spent their life savings on advertisements for the event(s) would be embarrassed or upset. Although a small minority expressed disappointment each time, most continued to believe Harold. Why?

It’s all about how the brain manages to rationalize or resolve two conflicting concepts: a state called cognitive dissonance. For example, people know that smoking kills, but they continue to smoke. These dissonant thoughts don’t work well together. People resolve the issue by removing one of the two conflicting concepts. Quitting tobacco is much harder than rationalizing that smoking is unlikely to kill you because you are a healthy individual, and anyway, everyone dies of something. In other words, changing your opinion (that smoking can kill you) is much easier than changing your behavior (smoking). So the dissonance is resolved by rationalizing your opinions, even if that leaves you believing something strange.

In Harold’s case, each time he could demonstrate how his calculations (based on interpretation of scripture) had been slightly wrong. By admitting a small personal failing, he managed to refocus his followers’ actions around the new date. For his followers, it was much easier to accept that their leader had forgotten to add a couple of years in his equation than to believe that their Rapture-targeted behaviors were misaligned or even laughable. The deeper they were involved in Harold’s prophecies, the more pride they had at stake, the more cognitive dissonance they had to resolve, and so the more likely they would be to grasp on to any explanation that Harold could provide.

However, after his October 21, 2011 prophecy, Harold stopped providing new dates and seemed to be somewhat chastened.

The question constantly arises, where do we go from here? Many of us expected the Lord’s return a few months ago, and obviously we are still here. Family Radio is still operating. What should be our thinking now? What is God teaching us? In our Bible study over the past few years, we came to the conclusion that May 21 and October 21 were very important dates in the Biblical calendar. We now believe God led us to those dates, but did not give us complete understanding. In fact, we did not understand at all the correct significance of those two dates. We are waiting upon the Lord, and in His mercy He may give us understanding in the future regarding the significance of those two dates.

Maybe this new outlook is partially due to his award of the 2011 Ig Nobel mathematics prize (jointly with several other prophets) for “teaching the world to be careful when making mathematical assumptions and calculations.”

Provide reasons for people to use
If you expect that users will be conflicted about the product or service you offer, provide them with many reasons they can use to resolve cognitive dissonance and keep their pride intact.

Online, cognitive dissonance can be brought about by effects such as buyer’s remorse, in which the purchaser struggles to justify the high purchase price and their desire for an item in comparison to their subsequent feelings of the item’s worth.

Sites help users resolve this cognitive dissonance by giving them reasons and evidence that bolster their satisfaction with the product (positive reviews; images of famous people using the product; and promises of hard-to-quantify benefits, such as social approval brought about by using the product) rather than letting them resolve the dissonance by returning the product.

The Best Made Company sells axes. One of its models was exhibited by the Saatchi Gallery in London, instantly turning it from a utilitarian object into a work of art. Painting stripes on the handle in limited numbers per design added to the exclusivity and thus desirability (see also the Tom Sawyer effect, in the chapter on Gluttony).

Lowes is a hardware company that also sell axes. At Lowes, a similar hickory handled felling axe costs $30. The $30 option comes with a lifetime guarantee, so why would you choose the $300 version? Mainly because Best Made offers many superlatives that help to ease cognitive dissonance. Its product description reads more like a manifesto to the outdoors lifestyle than a listing of features.

If you were to point out to owners of this axe that they’d just paid about ten times too much money for something used to chop wood, they would have plenty of ammunition to fire back. Clever marketing on the site turns a utilitarian purchase into a search for exclusive art, thus resetting customers’ pricing expectations. Continuing the marketing message through to the packaging of the item ensures that it is reinforced when customers receive the goods and every time they look at the product subsequently.

Buyer’s remorse: You can spend $300 or you can spend $30. In both cases you get a hickory handled felling axe. (left image:, right image:


To prevent buyer’s remorse, get customers to imagine the experiences they’ll have with your product or the way that others will react when they see the customer using your product. Take the customer in their mind’s eye to a contented future with the product and then make them look back on the current time as a pivotal decision point.

Continuing with the axe example, consider this quote on the About Us page: “Best Made Company is dedicated to equipping customers with quality tools and dependable information that they can use and pass down for generations. We seek to empower people to get outside, use their hands and in doing so embark on a life of fulfilling projects and lasting experiences.” These words are aimed at making you jump into the future and look back on now. How could you not buy something that promises a fulfilling life full of lasting experiences?

To resolve buyer’s remorse if it still happens, the trick is not to hide the return path, but to make it easier for customers to resolve the dissonance by changing their opinions instead. Because people are biased to see their choices as correct (see the description of confirmation bias in the Change Opinions pattern that follows), any supporting evidence can reinforce the initial opinions that led them to choose your product, help them rationalize their decision, and thus leave them happier with their initial choice. It is therefore important to use the same style of messaging throughout the site, from product pages through to the support and warranty/returns sections, and on all other collateral such as documentation sent with the product.

How to provide reasons
  • Give purchasers plenty of reasons to want your product. Provide testimonials, reviews, and lifestyle images. Help them visualize a rosy future that includes your product. This is just as important after the purchase as before. Don’t have a glossy sales page and a dull support page. Make it clear to existing owners that they did the right thing.
  • Add something cheap but unique to your product offering. Best Made place their axe in a wooden crate lined with “wood wool” (shavings). This costs them comparatively little but boosts the appeal of the product by giving owners self-reassuring evidence that they received something special.
  • Hire good product packaging and site designers. Presentation—how the product looks—can determine its price point. Utilitarian or bohemian?

Social proof: Using messages from friends to make it personal and emotional

Pride means caring what friends think about us and our activities. We’re proud when our friends praise us for something we’ve done, and upset if our friends disapprove. Much of our behavior is determined by our impressions of what is the correct thing to do. Our impressions are based on what we observe others doing.

Those others don’t have to be our friends. In a new situation we may follow the cues of total strangers. Most of those strangers could also be new to the environment, but we still make the assumption that they have a deeper understanding of the situation. Experts, celebrities, existing customers, and even the “wisdom of the crowd” can all serve as drivers for how we behave. This influence is known as social proof: “If other people are doing it, it must be right.”

If we see a tip jar full of bills, we are more likely to tip. If we see a nightclub with a line outside, we’re more likely to think it’s a popular venue. If we see a restaurant full of happy people, we’re more likely to think that eating a meal there would be worthwhile. That’s why baristas “prime” their tip jars in cafes, why nightclubs keep a slow-moving line outside even if the club is quiet inside, and why restaurants seat people at the window seats first thing in the evening.

It doesn’t hurt Apple to have long lines outside its stores on product release days. (Well, except for the Chinese release of the iPhone 4S, in which there was such a large crowd that the police made the stores cancel the release.) This just provides additional social proof that Apple’s products must be worth having because so many people line up to buy them.

The line outside the Chicago Apple store on a cold morning two weeks after white iPads were first released. The fact that people were prepared to stand outside at least half an hour before opening time for the vague possibility that this store had some iPads in stock projects strong social proof that Apple’s products must be worth having.


Dispel doubt by repeating positive messages
Hearing the same positive message several times from different trusted sources can provide the social proof that helps users form a decision.

In 1969, Stanley Milgram was running studies looking at conformity. He’s best known for a study in which he determined that subjects would give supposedly lethal shocks to another person if told to by an authority figure. However, he also ran slightly more benign studies that looked at how influence varies with different numbers of sources. He had a paid helper stand on a busy sidewalk and look up at the (empty) sky. He noted that approximately 40 percent of people passing would also look up. With two confederates, that number rose to 60 percent. When he paid four people to stand together and look up, around 80 percent of people passing would also look up.

If more people are doing something, it lends additional credibility to the activity. If you hear about the same product from several different sources, you tend to attribute more positive views to it than a product you were unfamiliar with. In other words, familiarity doesn’t breed contempt, it breeds reassurance.

Showing what others bought and what is frequently bought together serves as two additional social proof reinforcements for the item on the page. (


People rely on social proof more when they are unsure what to do. New users, people shopping for infrequent or unfamiliar purchases, or people seeking expertise are all likely candidates for social proof persuasion.

To give customers several converging statements that add to social proof, sites also provide white papers of case studies, indications of how popular a particular item is (number sold, number left in stock, or even a “sold out” label), recommendations for complementary products or accessories, and product reviews.

Testimonials are another type of social proof. If you offer testimonials, make sure they come from people who appear qualified to make the statements, and that you give enough details about these people so that a reader can validate that they exist.

Because the information from each of these sources complements the other sources, and because they appear in different places around the site, users tend not to notice that the same basic message is repeated to them in different ways each time.

It’s important that the social proof examples you use guide people in the direction that you want. Making it clear that a large group of people engage in the behavior you don’t want (even if you emphasize it only to say “don’t do this”) legitimizes that behavior in people’s minds and may provide social proof in the wrong direction. For instance, a campaign against teen drinking that tries to shock by saying what proportion of teens drink may work for adults, but will have the opposite effect on teens. (“Hey—all the others are doing it, so why don’t I?”)

The best forms of social proof come from outside the direct sphere of influence that a site has. Reading positive statements about a product or company on a supposedly neutral third-party site can have greater social proof outcomes than reading the same statements on the company’s site. By 2011, only 13 percent of consumers purchased products without first using the Internet to review them. More customers think it’s important to get reviews from other consumers than from professional reviewers or consumer associations.

This has led to the rapid growth of pay-to-blog advertising and sponsored posts. Companies exist to match advertisers with bloggers (,,,,, and, and a whole army of bloggers exists to take advantage of these paid endorsements. Many are in the home, family, and parenting blog categories and on tech “review” sites.

LinkWorth is just one of many companies who match advertisers to bloggers. The pseudo-originality of the blog post—each one written by a different blogger, but on the same theme—increases search engine optimization and adds social proof. (


The proliferation of for-pay blogging caused concern about both the impartiality of reviews written online and also the blurry line between commercial sites and blogs that were basically shills for an organization.

In 2009 this led the Federal Trade Commission (FTC) to update its testimonial and endorsement guidelines for the first time since 1980.

When there exists a connection between the endorser and the seller of the advertised product [that] might materially affect the weight or credibility of the endorsement (i.e., the connection is not reasonably expected by the audience) such connection must be fully disclosed.

The maximum fine is $11,000—although this seems to be aimed more at celebrities on talk shows than at mommy bloggers. Now the industry has several different yet similar codes of conduct, all aimed at allowing bloggers to receive money from advertisers for giving honest opinions. The money hasn’t disappeared, but the honesty (and the fact that blog posts are sponsored) should be more apparent.

The fact that bloggers can leave less favorable reviews probably won’t even harm sponsors considerably. Only 4 percent of people would change their mind about a product or service after reading one negative review, and it takes three negative reviews before the majority of users would change their minds. The proportion of reviews can also play a role: Three negative reviews may mean very little in comparison to 300 positive reviews.

How to use social proof
  • Try to create several statements that back up the same general positive concept about your product or service. Users are more likely to believe you if they hear several variations on the same theme.
  • Get statements placed on different sources or sites. Seemingly impartial reviewers have more credibility, and hearing the same statement from multiple sources also improves social proof.
  • Place statements at locations on the site where they’ll be seen by new users, people shopping for infrequent or unfamiliar purchases, or people seeking expertise.
  • Describe your process, product, and so on as the accepted norm—for instance, the industry standard or reference item. Being seen as a standard gives the product implied social proof.
  • Work with common stereotypes of behavior—if it’s commonly held that people will do X in situation Y, then reinforce that stereotype to your advantage, as it plays to social proof.
  • Use site statistics to impute social proof—for instance “70 percent of our business comes from client referrals” demonstrates that clients like the business enough to recommend it to others.
  • Make sure the social proof example you use emphasizes your desired behavior rather than trying to dissuade people from the opposite behavior. Don’t even raise the opposite behavior as an option.

Personal messages hit home
Messages aimed directly at the user grab attention. Messages that come from friends and trusted others have even more effect.

To reach Hanakapiai Beach on Kauai in the Hawaiian islands, you have to hike a couple of miles along the beautiful but up-and-down Kalalau trail along the Na Pali coast. The visual reward makes the hike worthwhile, and it would be unfair to spoil it for you by showing you photos here. Instead, I’m going to show you photos of the warning signs that you see just before you reach the beach.


On the left is the series of three official signs. Each is carefully crafted to give a depiction of the dangers that await you, backed up by stern sounding warnings. That clean, official, indirect voice keeps things passive and impersonal and thus relatively easy to ignore.

On the right is the unofficial sign, found just a few yards further down the trail. Obviously hand-carved by a concerned amateur, this sign talks less about the natural features of the beach and more about the outcome: “Killed? Yikes!” This more personal approach (backed up with near real-time updates on the death toll) is much more likely to hit home with passing hikers.

Back in the tech world, Jimmy Wales’ “personal appeal” to raise funds for Wikipedia has a positive effect on donations. Wikipedia runs annual fund raising drives, and in 2011 the banner ads it used to accompany the fund raising were crafted through a series of A/B comparison tests to ensure maximum click through, followed by appeal pages designed to tell a story that would maximize conversion and donation amounts.


Wikipedia’s A/B tests allowed them to work out that the most effective messages came from Jimmy Wales (the founder and public face of Wikipedia) and included a trustable explanation as to why the donations were needed. Thus, it came as close to being “personal” as is possible from a person that donors had probably never met.

Social networking sites use pseudo-personal messages in an attempt to drive viral adoption. For instance, Google+ tells you your friends have invited you, so you feel like it’s a recommendation from them to use the service. All that actually happened was that your friend added your e-mail address to their Google+ Circles.

Did Chris really invite me to join him? No, he just added me to his circles. But it sounds more like a recommendation this way.


After you sign up and add some people to your own circles, you perpetuate the social proof effect. In addition, when you reciprocate with an “add,” Google informs the person who first added you that “they want to hear from you.”

The recipients of my “invitation” now apparently want to hear from me. Wow, I’d better start using the service more diligently!


Even more insidious is LinkedIn and Facebook’s habit of using your name and likeness in ads seen by your friends and contacts saying that YOU recommended/used/did this thing, so your contacts should, too.

An e-mail from LinkedIn uses my connections’ names and likenesses to convince me to do something. If all of these respectable professionals are doing it, maybe I should be too.


Interestingly, Facebook first tried this in 2007 with its Beacon product. It bombed because it was hideously intrusive, to the point of sharing details of purchases that individuals made at third-party sites on their Facebook walls. After much public outcry it was shut down in 2009.

Facebook’s demonstration of how advertisers on their site can take advantage of social proof to place adverts in the news feed by piggybacking on your friend’s posts


Now, Facebook has launched a similar feature called Sponsored Stories. If friends use the name of a company or product in a post that they make, or “Like” a company elsewhere on the web, this feature shows the logo or other advertising visuals for that company or product attached to the friends’ posts, called out in the right column among other ads, in the ticker, and more recently in the news feed. The main difference in functionality and presentation this second time is that the feature works much more like a social proof than a broad spam.

The more similar the subjects of the social proof are to you, the more likely you are to respond favorably. That’s why the social media implementations work so well—the social proof is provided by people within your network. However, even a weak form of social proof can be sufficient to tip the balance. You may have noticed online advertisements for car insurance, work-from-home schemes, or mortgages that highlight how someone in your neighborhood has saved money, earned millions, or otherwise improved their life. Obviously all they are doing is geolocating your IP address, but the end result is a marginally more convincing advertisement.

Even weak forms of social proof can be effective. Advertisers wouldn’t pay the extra money to customize advertisements based on the approximate location of your Internet connection unless there was some payback for them.


Will users call you out for using social proof? No. Most individuals—even when told about social proof—claim that other people’s behavior doesn’t influence their own. So they don’t believe that they will fall for these tricks even while they are falling for them.

How to make it personal
  • Prime users to do what you want by showing how other people have already done that thing.
  • Make sure that these “other people” share characteristics with your users so that users identify with them as much as possible. Using someone’s friends or contact list has additional influential power.
  • If it’s likely to benefit you, show what other people did in a similar situation. Case study white papers,’s “people who viewed this also viewed these” and “n percent ended up buying…” widgets are good examples.
  • Encourage Likes and +1s, comments, retweets, and responses to your social media activity. The social proof provided by a large number of recommendations can be highly convincing.
  • Social proof works best if the social group used as the proof closely matches the current user. Use your users’ profile information to craft a story that matches their needs well.

Gain public commitment to a decision
Make a user’s decision public and they will feel more inclined to carry through with the action and defend the decision.

New year’s resolutions are hard to keep: 22 percent of people fail after one week, 40 percent after one month, and 81 percent after two years. Quitting smoking, reducing alcohol consumption, and losing weight are all hard to do.

Although the only tried-and-true method to lose 10 pounds in 48 hours is food poisoning, companies like Weight Watchers know that the social element—regular meetings where you “weigh in” and share your progress with others—are big drivers for successful weight loss and long-term weight maintenance. The key here is the shared commitment that you make to reach your goal. By meeting with and sharing encouragement with others in a similar position, it becomes easier to stick to your plans.

Getting that commitment is one thing. Sharing it with others is even more powerful. Now the user faces social reprobation if they don’t follow through. This could be as simple as adding the user’s name to a wall of commitments, or e-mailing the referrer of the user to say they’ve signed up. Commitment to a goal is much more concrete if the commitment is written down.

Many sites and apps exist to assist you with your efforts. One big motivational technique that several of the sites use is to replicate the social element by making your goals public. This way, people in your social network can see your planned and actual workouts, and leave encouraging comments for you. Runkeeper, Fitocracy, Fleetly, and MapMyRun/MapMyRide all have publicly accessible pages for each user and optional sharing via other social media such as Facebook and Twitter.

The GymPact site and iPhone app allow you to set goals (“pacts”), put money (“stakes”) against them, and then check in to the location to verify that you attended. People on average miss 10 percent of their commitment days. When this happens, they have stakes deducted from their account. That money goes to reward people who did attend. (


HabitForge, 21habit, and GymPact take a different tack: A third party (the site or app) holds you to your commitment. 21habit and GymPact even include a financial incentive. With 21habit you pay the site up front, and then on each day that you complete your activity you get to reclaim your day’s dollar. Skip a day, and your money goes to charity. Even though this might at first seem like a straight contract between the individual and the site, the act of telling the site (and subsequently being reminded on a daily basis) makes the activity external—public, rather than internal—private.

How to gain public commitment
  • Persuade your users to give you access to post to their social media accounts. You probably don’t have to be deceptive: If you have done a good job of selling the product or service, then it should be easy to explain how a public commitment can make the user more likely to follow through.
  • Create an environment such as a forum where users can form groups with a shared commitment to performing an activity that you care about. Peer pressure can keep the group more committed.
  • Display a simple metric of “success” that shows at a glance whether users are progressing toward their stated goals. This metric should be easily interpretable by users and by their extended social network. Allow users to “share” this metric as a widget on other sites to gather even more public commitment.
  • Combine public commitment with an affiliate program. This gives users more motivation to share because they make money from the process of expressing their commitment.

Change opinions by emphasizing general similarities
People don’t like to change opinions and will ignore counterfactual information. Instead, show them how similar your desired position is to their current opinion.

Changing your opinion on something involves admitting that you were wrong. The more public your initial statements, the more pride you must swallow in moving to the new perspective.

This is so deeply ingrained that we even have a tendency to search out and interpret information in a way that confirms our current beliefs. More interestingly, after we find sufficient information, we stop. We don’t tend to seek out information that might prove us wrong. This is known as confirmation bias.

Clever sites that need to sell people on an idea that involves making them change their minds do it by giving users selective information that confirms their preconceptions while also supporting the concepts that the site wants to get across.

This is easier to achieve than you may think. Stephen Colbert hosts a late-night comedy show in the persona of an outraged Republican, while actually satirizing right-wing policies. Or maybe I only think he does. According to a study run by researchers at Ohio State University, viewers with right-wing tendencies still find the show funny. “Conservatives were more likely to report that Colbert only pretends to be joking and genuinely meant what he said, while liberals were more likely to report that Colbert used satire and was not serious when offering political statements.”

Colbert’s response when asked about his political leanings was “I have no problems with Republicans, just with Republican policies.” By creating parodies of these Republican policies, Colbert could be seen as using Republican-held beliefs to change Republicans’ perceptions.

Stephen Colbert: Funny to both sides of the political divide, despite parodying Republican philosophies (Photo: Joel Jefferies from Comedy Central site)


Online, there are few better examples of changing people’s opinions by expressing similarities than DivaCup. This company discusses a generally taboo topic (menstruation) and changes women’s minds about abandoning traditional practices (tampons and pads) and trying something that at first glance seems like it couldn’t work (an insertable silicone cup). It achieves this by first co-opting the audience into agreeing that yes, they have experienced the issues that the site lists, and then going on to show how the DivaCup solution is similar-to-but-better-than what the audience is currently doing. This then allows them to emphasize the positive elements of the product that people couldn’t disagree with wanting (clean, hygienic, comfortable, green, and so on).

DivaCup’s “have you ever…” section gets women thinking about situations that are similar to their lives. (


How to emphasize similarities
  • Don’t try to persuade people that they should change. Instead, show them how they are already doing elements of what you want them to do.
  • Emphasize the positive and the similar elements rather than requiring them to think about the negative and the unfamiliar aspects.
  • Talk in general terms that can be interpreted positively by any user. “Family values” is a positive term to everyone who hears it, regardless of how they interpret it.
  • Talk about aspirations. “Yes, I do want to lose weight/find a partner/make tons of money/…”—people feel motivated to achieve their aspirations even if they never actually work toward them.

Use images of certification and endorsement
Membership of third-party certification schemes is cheap in comparison to the conversions it can produce. Or just create your own certification, promise, or guarantee.