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Surrounded by Idiots

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Surrounded by Idiots PDF

The Four Types of Human Behavior and How to Effectively Communicate with Each in Business (and in Life)

People are either Red, Yellow, Blue, or Green. 

And we’re not quoting a newly found CCR song or talking about political parties—these are the four behavior types according to Swedish communication expert Thomas Erikson.

Find out more about each of them in our summary of his runaway bestseller:

Surrounded by Idiots.

Who Should Read “Surrounded by Idiots”? And Why?

Surrounded by Idiots is justly marketed as the perfect book for human resource workers and managers: if you are one, Erikson’s bestseller will undoubtedly help you categorize the employees you’re in charge of into easily manageable categories.

However, since it can help anyone do the same, it is also perfect if you want to build a more stable and more lasting relationship with someone, be that person a coworker, a friend or even a partner.

About Thomas Erikson

Thomas Erikson is a Swedish lecturer and author.

He has written three books so far. He made his name with Surrounded by Idiots in 2014, which has been translated into 40 languages so far and is one of Sweden’s best-selling non-fiction books of the past half-decade.

Erikson’s other two books can be described as sequels to his debut: Surrounded by Psychopaths is a book about manipulation, and the recently published Surrounded by Bad Bosses is a book about, well, bad bosses.

Find out more at https://thomaserikson.com

“Surrounded by Idiots Summary”

The word “idiot” is defined by the Merriam-Webster Dictionary as “a foolish or stupid person.” 

As far as Thomas Erikson is concerned, however, an “idiot” is merely someone who has a different behavior profile—and, consequently, style of communication—than the one dubbing him one.

Of course, this is not something Erikson believed when he was young when he too “pigeonholed people into two groups—good and sensible people and all the rest, the people who didn’t seem to understand anything at all:”

And how did Erikson’s worldview change? 

Well, when he was 25, he was supposed to interview a 60-year-old CEO by the name of Sture who told him that “he was surrounded by idiots.” The more Thomas thought about this sentence, the less he was able to understand it.

“But who hired all these idiots?” he eventually asked Sture, fully aware that it could have been only him and nobody else.

Of course, at this point, Sture wanted to fetch a shotgun and shoot Thomas (his words), but Thomas wanted to make a pretty important point. 

Namely, even Sture didn’t honestly believe that he was surrounded by idiots: he was just incapable of communicating with them properly. And we’ve already shared the reason with you: Sture didn’t know that people have different behavior profiles and that you can’t communicate with everyone in the same manner.

And this is what Erikson’s Surrounded by Idiots is all about: “the world’s most widely used method to describe the differences in human communication.”

The method is called the DISA or DISC system, acronyms that stand for Dominance, Inducement, Submission, and Analytic/Compliance ability. These four terms are the primary behavior types that describe how people see themselves in relationship to their environment. Each of these behavior types is associated with a color: Red, Yellow, Green, and Blue.

But before we get to the system itself and its applications, it would be a good idea to take a brief history tour.

People Have Always Been Like This

Even though the categorization of people in accordance with some theoretical behavior profile may seem like a modern invention, the truth is that in all cultures, there has always been a need to categorize people. 

And interestingly enough, many of these categorizations can be considered precursors to the DISA system. Erikson compares it to the two most familiar.

The Classical World: Humorism

Four centuries before Christ, Hippocrates, the father of medicine, devised a theory that every person’s temperament is the product of the (dis)balance between the four humors—i.e., the four bodily fluids—that flow inside him: blood, yellow bile, black bile, and phlegm.

The system, further developed by the Roman physician Galen, is now called the humoral system, and it suggests that there are four fundamental personality types:

  • Sanguine: whose temperament is controlled by the excess of “blood” (Latin: sanguis) in his body. These people are happy-go-lucky optimists who spread positive vibes around them.
  • Choleric: whose temperament is controlled by his “yellow bile” or his liver (Greek: chloe). Choleric people are fiery and temperamental and sometimes frighten those around them.
  • Melancholic: whose temperament is the result of an excess of “black bile,” supposedly found in the spleen (melaina chloe means “black bile” in Greek). Melancholy people are gloomy pessimists.
  • Phlegmatic: whose temperament is influenced by his brain from where the Greeks believed mucus (Greek: phlegma) comes from. Phlegmatic people, just like mucus, are viscous, i.e., slow and sluggish.

As you’ll see in a moment, these four personality types correspond to the ones theorized by the DISA system: sanguine people are yellow, choleric are red, melancholic are blue, and phlegmatic are black.

The Aztecs and the Elements

Many centuries after Hippocrates, on the other side of the Atlantic, the Aztecs developed a similar proto-psychological theory based on something they knew quite well: the four elements:

  • Fire people were warriors and leaders, explosive and hot-headed.
  • Air people were much more easygoing but quite captivating and determined.
  • Earth people were workers, stable, and secure.
  • Water people were wallflowers, quiet and secure, but observing and smart as well.

Once again, this system corresponds to the DISA behavior types: fire people are red, air people are yellow, earth people are green, and water people are blue.

Walter Moulton Marston and the DISA System

You probably don’t know this, but the guy who laid the foundations for the DISA/DISC model was also the guy who invented the lie detector and—get this—created the character of Wonder Woman! 

At least at the present moment, we can think of nobody as ludicrously versatile as Walter Moulton Marston.

Anyway, Marston noticed that the distinct differences between people can be conveniently described via four different relationships between an individual and his environment, which he explained in this manner:

•  Dominance produces activity in an antagonistic environment.
•  Inspiration produces activity in a favorable environment.
•  Submission produces passivity in a favorable environment.
•  Compliance produces passivity in an antagonistic environment.

Erikson—and most people nowadays—use Stability instead of Submission and Analytic ability instead of Compliance (because these two relationships between an individual and other people/his environment seem to better explain people’s behavior types) and further describe these traits thus:

Dominance relates to how a person approaches problems and deals with challenges. It is all about acting.
Inspiration is about being able to influence and convince others to do something. Inspiration is about interacting.
Stability is about an individual’s receptiveness to change, in that a strong need for stability means a person is resistant to change (the “good old days” guy) and a lower need for stability means a more adventurous person. Stability is all about connection.
Analytic ability is about following rules and regulations. Analytical people can’t accept that things may go wrong or happen at random. Analytic ability is all about organization.

Before we go one, here’s one of the many wonderful graphs in Surrounded by Idiots: it sums up the above much better and it will make even more sense in the next section of our summary.

An Overview of the System

Now, the system Erikson uses in Surrounded by Idiots is the DISA system. The only difference is that he uses colors instead of the four traits described above—mainly because he has found out, via experience, that people remember the system better this way.

In Erikson’s system:

• Dominant people are Red people
• Inspiring people are Yellow people
• Stable people are Green people
• Analytical people are blue people

In the real world, only 5% of people have only one color that dominates their behavior, and over 80% have a combination of two colors along whose spectrum their behaviors can be described. The rest—15%—are dominated by three colors.

Throughout the book, Erikson focuses on the single colors individually “because they are the fundamental components of a person’s behavior.” “It’s like a recipe,” he writes, “we need to understand all the ingredients before we bake the cake.” 

Before we move to the colors, some interesting things to have in mind (and come back to once you finish the other section):

• The most common behavior among people is Green in combination with another color (or even entirely Green behavior). The least common is entirely Red behavior or Red behavior in combination with one other color.
• Blues and Reds, as well as Greens and Yellows, are complementary types: grouping people like that makes invincible teams (as well as long-lasting friendships and marriages)
• Because in the real world, most people are dominated by two colors, here is the best combination in the spectrum: Blue/Green and Red/Yellow.
• In most cases, Reds and Greens fail to work as a team, and, due to mutual disliking, are better off grouped otherwise.
• Finally, Yellow and Blue is the worst combination of all: you don’t want them in the same room, whether as workers, friends, or lovers.

Now—onto the colors!

Behavior Types: Descriptions, Perceptions, and Communication

Red Behavior: How to Recognize a Real Alpha and Avoid Getting in His Way

Core behavior pattern (in the words of the author):

Reds are quick and more than happy to take command if needed. They make things happen. However, when they get going, they become control freaks and can be hopeless to deal with. And they repeatedly trample on people’s toes.

In a few traits: quick reaction, maximum effort to control, minimal interest for caution in relationships, direct action, tendency to avoid involvement

Adjectives that describe Reds: aggressive, ambitious, strong-willed, goal-oriented, pushing, problem-solver, pioneer, decisive, innovator, impatient, controlling, convincing, performance-oriented, powerful, results-oriented, initiator, speed, timekeeper, intense opinionated, straightforward, independent

How they perceive themselves: driven, decisive, prompt, persuasive, resolute, competitive, determined, strong-willed, ambitious, independent, time-conscious, results-oriented

Body language: they keep their distance from others, have powerful handshakes, lean forward aggressively, use direct eye contact and controlling gestures

How to talk to them: with Reds, you have to be sincere, direct, and argumentative; they hate beating around the bush and are less receptive if you use euphemisms; however, they will use any weakness in your argument against you, so stay strong and firm with them

What annoys them: Reds hate unchallenging and mundane tasks more than they hate Death itself, so if you want them on your team, give them something difficult to do (and, also, a team to command)

Famous Reds: Steve Jobs, Venus Williams, Margaret Thatcher, FDR, Barack Obama, Mother Teresa

Yellow Behavior: How to Recognize Someone Whose Head Is in the Clouds and Get Him Back to Reality Again

Core behavior (in the words of the author): 

Yellows can be amusing, creative, and elevate the mood regardless of who they’re with. However, when they are given unlimited space, they will consume all the oxygen in the room, they won’t allow anyone into a conversation, and their stories will reflect reality less and less.

In a few traits: rapid reaction, maximum effort to involve, minimal interest in routine, future time frame, impulsive action, tendency to reject isolation

Adjectives that describe Yellows: talkative, enthusiastic, persuasive, creative, optimistic, social, spontaneous, expressive, charming, full of vitality, self-centered, sensitive, adaptable, inspiring, needs attention, encouraging, communicative, flexible, open, sociable, imaginative, easygoing

How they perceive themselves: enthusiastic, inspiring, open, convincing, charming, optimistic, creative, easygoing, outgoing, flexible, spontaneous, communicative

Body language: they are tactile, relaxed, and jocular, show friendly eye contact, use expressive gestures and often come close to the one they talk to

How to talk to them: Yellows are most receptive when you are open and amiable to them, which means, try to laugh at their jokes and insert one or two yourself; also, since Yellows are disorganized, it’s better to provide them with a detailed list of their responsibilities after the oral part of your discussion is over

What annoys them: Yellows don’t want to be isolated, so don’t put them in solitary offices; they also don’t want to be surrounded by negative energy, so don’t put them around Blues; finally, when they ask you to organize the next teambuilding event—don’t hesitate to say “yes”

Famous Yellows: Oprah Winfrey, Robin Williams, Ellen DeGeneres, Pippin (from LOTR) and Han Solo (from Star Wars)

Green Behavior: Why Change Is So Difficult and How to Get Around It

Core behavior pattern (in the words of the author):

The friendly Greens are easy to hang out with because they are so pleasant and genuinely care for others. Unfortunately, they can be too wishy-washy and unclear. Anyone who never takes a stand eventually becomes difficult to handle. You don’t know where they really stand, and indecision kills the energy in other people.

In a few traits: calm reaction, maximum effort for connection, minimal interest in change, current time frame, supportive action, tendency to reject conflict

Adjectives that describe Greens: patient, relaxed, self-controlled, reliable, composed, loyal, modest, understanding, lengthy, stable, prudent, discreet, supportive, good listeners, helpful, producer, persistent, reluctant, thoughtful, conceal feelings, considerate, kind

How they perceive themselves: friendly, considerate, predictable, discreet, calm, pleasant, stable, thoughtful, reliable, patient, team player, good listener

Body language: they are relaxed and come close, act methodically, tend to lean backward, use very friendly eye contact, and prefer small-scale gestures

How to talk to them: Greens don’t want to be in the spotlight, so only one-on-one meetings with them should work—even when you want to praise their work; on the other hand, when you criticize them, try to make sure they know that nothing is personal because they have fragile egos

What annoys them: Unlike Yellows, Greens like privacy and don’t want a sudden change in plans. So, don’t make them redo the work they’ve already done, and don’t ever reassign them to new projects in the middle of an ongoing one.

Famous Greens: Mr. Rogers, Mahatma Gandhi, Michelle Obama, Jimmy Carter, Jesus Christ

Blue Behavior: In Pursuit of Perfection

Core behavior pattern (in the words of the author): 

The analytical Blues are calm, levelheaded, and think before they speak. Their ability to keep a cool head is undoubtedly an enviable quality for all who aren’t capable of doing that. However, Blues’ critical thinking can easily turn to suspicion and questioning those around them. Everything can become suspect and sinister.

In a few traits: slow reaction, maximum effort to organize, minimal interest in relationships, historical time frame, cautious action, tendency to avoid involvement

Adjectives that describe Blues: conscientious, systematic, distant, correct, conventional, seems insecure, objective, structured, analytical, perfectionist, needs time, reflecting, methodical, seeks facts, quality-oriented, scrutinizing, rule-following, logical, questioning, meticulous, reflecting, reserved

How they perceive themselves: accurate, detail-oriented, orderly, systematic, cautious, logical, quality-oriented, thorough, correct, methodical, reflective, unassuming

Body language: they have closed body language and prefer to keep others at a distance, they either stand or sit, use direct eye contact and speak without gestures

How to talk to them: when you talk with a Blue, have your facts and arguments prepared beforehand, because, unless you know the answers to all of their questions, they will not take your idea seriously; so, work out everything in advance—minutiae included

What annoys them: Blues, unlike everybody else, crave bureaucratic organization and want well-thought-out plans; however, they also want enough time and space to execute them properly, so tight deadlines would never work in their case

Famous Blues: Bill Gates, Albert Einstein, Sandra Day O’Connor, Condoleezza Rice, Mr. Spock (from Star Trek)

Key Lessons from “Surrounded by Idiots”

1.      Why Are We the Way We Are?
2.      Ever Since Ancient Times, People Categorized People
3.      There Are Four Behavior Types—and You Are Probably a Combination of Two of Them

Why Are We the Way We Are?

It is difficult to answer this question, but, as we’ve told you before, it’s mostly a combination of heredity and environment (or, to be more precise, genes: 40%, family: 10%, and unique environment: 50%.)

Erikson goes a few steps further and talks about core values, attitudes, core behavior, moderated behavior, and environment, still making clear that at least one or two of these aspects of our personalities are beyond our choice.

He even shares with his readers a neat equation:

BEHAVIOR = f (P × Sf)

In other words, Behavior is a function of Personality and Surrounding factors, where our Behavior is that which we can observe, Personality is what we try to figure out, and Surrounding factors are things that we have an influence on.

Ever Since Ancient Times, People Categorized People 

Even though psychology didn’t really exist before Freud and Jung, people have categorized other people in accordance with some system ever since Ancient Greece.

It was then that Hippocrates developed his humoral pathology, according to which there are four personality types: sanguine, choleric, phlegmatic, and melancholic. The Aztecs developed quite a similar system as well, categorizing people in accordance with their relationship with the four elements: firey, airy, watery, and earthy.

In the 20th century, however, a guy by the name of Walter Moulton Marston developed a modern version of these categorizations called the DISA system, an acronym for the four most important traits according to the author: dominance, inspiration, stability (or submission, originally) and analytic ability (or compliance, originally)

There Are Four Behavior Types—and You Are Probably a Combination of Two of Them

Thomas Erikson—and many modern HR theoreticians—developed Marston’s system further and have now, for mnemonic reasons, color-coded it.

According to Erikson’s explanations in Surrounded by Idiots, people are either dominantly Red (dominant, direct, active), Yellow (inspiring, impulsive, influential), Green (stable, calm, supportive), or Blue (analytical, slow, cautious).

Only 5%, however, are exclusively dominated by one color, and just 15% can be described in a three-color range. The rest—80%—are dominated by two colors.

See our explanations above and find out which are your two colors.


Understanding human behavior is essential for effective communication and successful relationships, both in business and in life.

Thomas Erikson’s analysis in “Surrounded by Idiots” provides a practical framework to navigate diverse personalities.

By recognizing behavior types—Reds, Yellows, Greens, and Blues—we gain insights into communicating effectively and fostering productive environments.

Erikson’s work emphasizes adapting our communication styles to suit others’ preferences, leading to greater harmony and success in all interactions. Embracing the diversity of human behavior empowers us to navigate any situation with insight and skill.

Like this summary? We’d like to invite you to download our free 12 min app for more amazing summaries and audiobooks.

“Surrounded by Idiots Quotes”

We continually affect one another in some form or other. The trick is to try to figure out what’s there, under the surface. And this book is all about behavior. Click To Tweet Nowadays you might call a Red person bold, ambitious, driven, but also potentially hot-tempered, rash, or dominant. You quickly notice a Red person because he doesn’t make the slightest effort to conceal who he is. Click To Tweet Life is a banquet, and Yellows will see to it that they savor every bite. They are driven by merriment and laughter. And why not? The sun is always shining somewhere. Click To Tweet The Green person is the most common. You’ll meet him virtually everywhere. What’s the easiest way to explain who he is? Well, I would like to describe him as being the average of all the other colors. Click To Tweet While a Green will just go with the flow, a Blue has all the right answers. In the background, he analyzes: classifies, evaluates, assesses. Click To Tweet

Our Critical Review

“A useful guide to communicating with the uncommunicable,” Surrounded by Idiots is (according to Publisher’s Weekly) a “dynamically presented and easy to grasp” exploration of human behavior types.

True, some of the book’s generalizations seem unconvincing and even far-fetched, but, in our opinion, the best aspect of the book is precisely its simplicity and directness, both in terms of the main idea and in terms of the author’s style. And we do believe (with Booklist) that most people can benefit from this book, especially those in the workplace.

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