How to persuade a crowd

This is the first in a series of blogs about "Groupology".

[Groupology (gru:p'oledzI) n. The study of Groups.]

How to persuade a crowd


In our line of work, creating digital communities, it is important to understand the nuances around how groups of people interact.  This means researching and answering questions such as: 

  • why do people join groups?
  • what motivates a group or team?
  • what drives groups to take action?

Fortunately, academics and scholars have been writing about these very topics for many centuries.  Fields such as philosophy, social psychology, evolutionary biology and organisational behaviour address these questions from different but overlapping angles.  

Combining this research with data from our present day digital communities provides some fascinating insights.

The Era of the Crowd

In 1895, the French social psychologist Gustave Le Bon[2] published La psychologie des foules translated into English a year later as: The Crowd: A Study of the Popular Mind[1].

He wrote at a time which he christened "The Era of the Crowd".  Up until the 19th century, power had resided with an elite minority — but this was beginning to change.  Indeed in his native France, the fallout from the revolution of 1789 had not yet settled.

However, he argued that the crowd was, on balance, not a force for good.  He was against the jury system and wary of our propensity for mob behaviour. He also described how groups are influenced and persuaded


"It will be remarked that among the special characteristics of crowds there are several—such as impulsiveness, irritability, incapacity to reason, the absence of judgment and of the critical spirit, the exaggeration of the sentiments, and others besides ..." — The Crowd: A Study of the Popular Mind, Chapter II, The immediate factors of the opinions of crowds. Part 1.


The interesting aspect is that many of the techniques described in his book are used in marketing, advertising and political campaigns to this very day.  Indeed it is well documented that a number of influential figures in the 20th century studied Le Bon in depth.  Next time you read or watch an advertisement or listen to a political broadcast see if you can spot any of these.

Techiques to persuade a crowd

The main techniques to persuade a crowd are:

  1. affirmation
  2. repetition
  3. contagion
  4. exaggeration
  5. symbols
  6. ill-defined words 
  7. but not(!)reasoning or logic

"When, however, it is proposed to imbue the mind of a crowd with ideas and beliefs—with modern social theories, for instance—the leaders have recourse to different expedients. The principal of them are three in number and clearly defined—affirmation, repetition, and contagion. Their action is somewhat slow, but its effects, once produced, are very lasting. " — Chapter III, The leaders of crowds and their means of persuasion, Part 2.

1. Affirmation

"Affirmation pure and simple, kept free of all reasoning and all proof, is one of the surest means of making an idea enter the mind of crowds. The conciser an affirmation is, the more destitute of every appearance of proof and demonstration, the more weight it carries. The religious books and the legal codes of all ages have always resorted to simple affirmation. Statesmen called upon to defend a political cause, and commercial men pushing the sale of their products by means of advertising are acquainted with the value of affirmation." — Chapter III, The leaders of crowds and their means of persuasion, Part 2.

Affirmation — the declaration that something is true — is a tool employed extensively by leaders of crowds.  This is true for religion, politics, finance, commerce and possibly every other field that deals with mass communication.  One never hears "This might be the best product on the market" — it is presented concisely as fact, or rather as a "truth":  "Ours is the number one product on the market".

And note that affirmation — kept free of all reasoning and all proof — will make an idea enter the minds of crowds.  To persuade a crowd one does not need (lengthy) proof or explanation. Save that for your one-to-one debate.

Crowds want clear and simple "truths".

2. Repetition

"Affirmation, however, has no real influence unless it be constantly repeated, and so far as possible in the same terms. It was Napoleon ... who said that there is only one figure in rhetoric of serious importance, namely, repetition. The thing affirmed comes by repetition to fix itself in the mind in such a way that it is accepted in the end as a demonstrated truth.

"... This power is due to the fact that the repeated statement is embedded in the long run in those profound regions of our unconscious selves in which the motives of our actions are forged. At the end of a certain time we have forgotten who is the author of the repeated assertion, and we finish by believing it.

"To this circumstance is due the astonishing power of advertisements. When we have read a hundred, a thousand, times that X's chocolate is the best, we imagine we have heard it said in many quarters, and we end by acquiring the certitude that such is the fact ... "

Chapter III, The leaders of crowds and their means of persuasion, Part 2.

The "mad men" of advertising have long known the power of repetition.  This psychological principle is precisely what makes advertising so successful — repeat the same message often enough and before long it has entered a part of the brain that incites action.  And what is more the brain will recall the message as a "truth" or "fact" because it can no longer remember otherwise!

3. Contagion

"When an affirmation has been sufficiently repeated and there is unanimity in this repetition ... what is called a current of opinion is formed and the powerful mechanism of contagion intervenes. Ideas, sentiments, emotions, and beliefs possess in crowds a contagious power as intense as that of microbes.

"Man, like animals, has a natural tendency to imitation. Imitation is a necessity for him, provided always that the imitation is quite easy ... Imitation, to which so much influence is attributed in social phenomena, is in reality a mere effect of contagion.

"It is by examples not by arguments that crowds are guided

"Contagion is so powerful that it forces upon individuals not only certain opinions, but certain modes of feeling as well ..."

Chapter III, The leaders of crowds and their means of persuasion, Part 2.


Contagion occurs when repetition begins to spread widely across the group: " ... It is by examples not by arguments that crowds are guided".  This is what powers memes and virals.  Digital technology only assists and enhances a basic principle that is deeply hard wired within our (lizard and mammalian) brains.

From Gangnam Style[9] to the Harlem Shake[10], fashion to fads and mass political movements, contagion is the pinnacle that many communicators are searching for.

"For individuals to succumb to contagion their simultaneous presence on the same spot is not indispensable."

— Chapter III, The leaders of crowds and their means of persuasion, Part 2.


The final pointis that even in Le Bon's time it was not necessary for individuals of the group/crowd to be physically in the same place for contagion to occur.  He cited the example of the Paris revolution of 1848 which spread across Europe and disrupted many a monarchy.

This has far reaching benefits for digital communication. 

The most fundamental and powerful principles for persuading a crowd are not only assisted but accelerated by digital technology.

4. Exaggeration 

"...Given to exaggeration in its feelings, a crowd is only impressed by excessive sentiments. An orator wishing to move a crowd must make an abusive use of violent affirmations. To exaggerate, to affirm, to resort to repetitions, and never to attempt to prove anything by reasoning are methods of argument well known to speakers at public meetings..."

—  Chapter II, The immediate factors of the opinions of crowds. Part 3: The exaggeration and ingenuousness of the sentiments of crowds. 

No crowd wants to hear "Our idea is slightly better than the others." or "This car goes a little bit faster". Crowds want to hear extremes and excesses. They are motivated and excited by it.

Exaggeration — excessive sentiments and affirmations —may be slightly off putting to the individual, but it is what sways the crowd. 

Almost every famous orator has put this technique to good effect: from Emmiline Pankhurst's "Freedom or Death"[4] to Mahatma Gandhi's "There is no salvation for India"[5], from Churchill's "I have nothing to offer but blood, toil, tears and sweat"[6] to John F. Kennedy's "A new frontier"[7] and Martin Luther King's "I have a dream"[8].  All used bold, excessive sentiments to talk to the crowd.

Barack Obama is an exceptional orator— see if you can spot this technique, and others listed here, in some of his speeches. 

5. Symbols

"When studying the imagination of crowds we saw that it is particularly open to the impressions produced by images. These images do not always lie ready to hand, but it is possible to evoke them by the judicious employment of words and formulas. Handled with art, they possess in sober truth the mysterious power formerly attributed to them by the adepts of magic. They cause the birth in the minds of crowds of the most formidable tempests, which in turn they are capable of stilling. "

Chapter II, The immediate factors of the opinions of crowds. Part 1.

Since time immemorial, the leaders of crowds have recognised the power of symbols.  Every major religion uses symbols to communicate.  The Roman Empire was especially fond of symbols — and this has been replicated through the ages by many aspiring empire builders.

The modern day empires that use symbols to great effect are the big global brands.  The multi national companies who are many times richer than some of the poorest countries in the world.  

As proven by cognitive and behavioural psychologists, anthropologists and other academics the human brain thinks in pictures.  Our language often reflects this "I see what you mean", "I see a bright future ahead of us" etc. but there is a reason why a picture is worth 1,000 words. And the correct symbol even more so.

National flags and symbols of pride evoke extreme emotion — good and bad.

Symbols — logos, branding, clothing, accessories — are also indicators of a particular "in-group". If you want to be part of "our group" you need to dress like us, talk like us, use the same products, drink the same coffee.

And the big multinational brands are totally aware of this. People buy Apple laptops and Nike trainers not just because they are intrinsically better.  In fact they are often made in the same factory in China as every other brand in the shop.

It is through a process of affirmation, repetition and contagion that these symbols take on a greater meaning. 

6. Ill-defined words

"Words whose sense is the most ill-defined are sometimes those that possess the most influence. Such, for example, are the terms democracy, socialism, equality, liberty, etc., whose meaning is so vague that bulky volumes do not suffice to precisely fix it. Yet it is certain that a truly magical power is attached to those short syllables, as if they contained the solution of all problems. They synthesise the most diverse unconscious aspirations and the hope of their realisation."

— Chapter II, The immediate factors of the opinions of crowds. Part 1.


There is a scene in the well known cartoon: "The Simpsons" when Homer Simpson is buying a new computer and the (very technical) sales assistant reels off an impressive but completely incomprehensible list of features: "This computer has a dual core, one point five gigahertz processor with a one gigabyte cache and a two-fifty-six megabyte random access memory... etc." (the list goes on for half a minute).  Those very specific words convey no meaning to Homer, nor to most of us.  

It is partly because the sales assistant was talking about features not benefits that was the problem. Simon Sinek's "Start with why?" is a great TED talk which explains this distinction perfectly[3].

But when talking to many, the choice of words you use impacts how influential you are. Words which are more conceptual, vague what Le Bon called "ill-defined" — are the very words which convey the greatest influence.

7. Not reasoning or logic

"Reason and arguments are incapable of combatting certain words and formulas. They are uttered with solemnity in the presence of crowds, and as soon as they have been pronounced an expression of respect is visible on every countenance, and all heads are bowed. By many they are considered as natural forces, as supernatural powers. They evoke grandiose and vague images in men's minds, but this very vagueness that wraps them in obscurity augments their mysterious power. They are the mysterious divinities hidden behind the tabernacle, which the devout only approach in fear and trembling.

— Chapter II, The immediate factors of the opinions of crowds. Part 1.


So the final point seems obvious once explained but initially is so counter intuitive!  Why would I not try and persuade the whole company with my well reasoned logic? Look at my beautiful spreadsheets and tables and pie charts etc. 

But this logic is lost on the crowd. 


Next time you listen to Barack Obama speak  see if you can identify any of the tools Le Bon wrote about. Does he use exaggeration? Affirmation? Repetition?  Does he speak in imagery and visionary language or use rhetoric, logic and persuasion?  

Or analyse famous speeches from the past  such as Martin Luther King's "I have a dream" speech (see references below).

Also look at how branding and advertising uses LeBon's techniques. Look at symbols  Nike, Coca-Cola, Apple  repetition of messages  straplines, company mottos, even jingles.

These principles are not just centuries old but go back millenia.  Man is a social animal and is influenced in highly social  and quite inflexible and predictable  ways.  As technologists, and specifically digital community creators, the more we research authors like Le Bon, the classic philosohpers like Aristotle and Socrates or organisational behaviourists like Max Weber it becomes clear that technology is not what defines how we interact.  It is our very hard wired brains that define which technology succeeds.

(p.s. If you spot any of the following techniques: affirmation, repetition, contagion, exaggeration, symbols, ill-defined words, but not reasoning or logic then please tweet me @leonhtong and @brightlemon).