TL;DR

This book challenges the “survival of the fittest” narrative by showing how friendliness and cooperation, not just strength or intelligence, drove human evolution. Our ability to work together, understand others’ perspectives (Theory of Mind), and form larger social groups led to innovation and survival. However, this same trait has a dark side - we can dehumanize outsiders when threatened. The book offers insights on how architecture, politics, and social movements can either promote or hinder our natural friendliness.

Rethinking “Survival of the Fittest”

We’ve all heard about survival of the fittest and natural selection. But what if that’s not the whole story?

The authors challenge this assumption beautifully:

I thought increased skill in manipulation or deception could explain the evolutionary fitness of an animal. What I discovered is that being smarter is not enough.

I used to think “fitness” meant being smarter, stronger, bigger, or faster. But here’s the kicker: Neanderthals had brains as large as (or larger than) ours. Homo erectus had similar physical and mental capacities to Homo sapiens. So why did we survive while they went extinct?

The answer lies not in our individual capabilities, but in our ability to work together.

How Friendliness Sparked Innovation

Friendliness drove this technological revolution by linking groups of innovators together in a way other hominin species never could.

Think about it: every major human achievement - from the wheel to the internet - came from people building on each other’s ideas. Cooperation isn’t just nice to have; it’s the engine of human progress.

Our unique ability to create complex languages allowed us to:

• Share knowledge across generations
• Coordinate large-scale projects
• Live in denser populations
• Exchange ideas rapidly

This created a positive feedback loop: more cooperation → more innovation → better survival → even more cooperation. But how did this cooperative communication feature nurture in us?

Understanding Theory of Mind: Our Social Superpower

Theory of Mind is our ability to understand that others have thoughts, feelings, and perspectives different from our own. It sounds simple, but it’s revolutionary.

Consider these everyday scenarios:

• When you see someone looking confused at a map, you offer help because you understand they’re lost
• When a friend cancels plans last minute, you wonder if something’s wrong rather than just feeling rejected
• When teaching someone, you adjust your explanation based on their facial expressions

Without Theory of Mind:

• We’d be trapped in our own mental bubbles
• Cooperation would be nearly impossible
• There would be no guilt, empathy, or genuine connection
• Other people would seem like unpredictable robots

This cognitive ability is the foundation of human society. It allows us to predict behavior, coordinate actions, and build trust - essential ingredients for large-scale cooperation.

Friendliness in Animals

The book compares chimpanzees with bonobos in their relationships. In chimpanese, the most aggressive and strong chimpanzee will be on top of the hierarchy. This makes them more unwelcoming toward other chimpanzees. However, female bonobos have fostered a friendlier approach. They attack those that try to hurt their babies or other female bonobos. The friendliest male bonobos have higher chance of passing their genes.

Others example of friendliness, is the self-domestication in cats and dogs.

Domestication occurs when animals who are friendly toward people become more successful at reproducing. We did not domesticate dogs. The friendliest wolves domesticated themselves.

Self-domestication in Humans

In domesticated animals, the adrenal glands are smaller than in their wild cousins, and smaller adrenal glands mean fewer stress-inducing hormones.

Self-domestication’s most powerful consequence was that it allowed us to live in larger, denser groups.

Darkside of Friendliness

As our species was shaped by self-domestication, our increased friendliness also brought a new form of aggression. ……… This allows us to blind ourselves to the humanity of people outside our group when we feel threatened. ……… As people felt more threatened by a particular group, Kteily found that dehumanization increased.

Breaking the Cycle

The book’s solution is surprisingly simple: get to know “them.” When outsiders become individuals with names, stories, and shared experiences, dehumanization becomes nearly impossible.

This is why diverse neighborhoods, integrated schools, and cross-cultural exchanges are so powerful. They turn “them” into “us.” The solution that book gives for our dehumanization of outsiders, is pretty simple. Just try to know them more. Then they aren’t outsiders anymore. You find out that these outsiders are also human and deserve human level behaviour.

Dehumanization & Freedom of Speech

Without threatening the freedom of speech, we can promote strong cultural norms against dehumanizing language. When someone on TV or in a newspaper or any medium refers to a person or group as less than human, alarm bells should start ringing. As citizens, we can make sure such language is never normalized. As the Italian poet Giambattista Basile wrote, “though the tongue has no bones, it can break a spine.”

I always thought about swearing. I asked myself why is it bad. Now I have a reason for it. It makes the target dehumanized. Which ultimately promotes lack of empathy toward that person.

Friendliness & Politics

Friendliness has political consequences. The higher your love for your group, race or color is, the more extreme your political ideas will be.

Our democracy remains far from perfect. But it is the only form of government that has reliably demonstrated the ability to harness the better angels of our nature while muting our darker side. …….. democracy is designed to promote the distribution, rather than the consolidation, of power, the celebration of differences rather than similarities, and equal rights for all.

Why Peaceful Movements Win

When we try to achieve a goal by force, it makes lots of sound and attracts lots of attention. But it lacks support. People will feel threatened by us and this creates a negative feedback loop.

• You shout and threaten
• The other side feels attacked and shouts back
• Everyone gets louder and angrier
• Nobody remembers what they’re fighting about
• Nothing gets resolved

To her surprise, peaceful campaigns had proved twice as likely to succeed, and violent resistance four times more likely to fail. …….. On average, peaceful campaigns involve 150,000 more people than violent campaigns. …….. One study found that extreme protest tactics, like roadblocks, destroying property, and interpersonal violence, although good for gaining media attention and publicity, actually decrease popular support for the movement.

Peaceful movements succeed because they:

• Attract more participants (including elderly, children, and risk-averse people)
• Generate sympathy rather than fear
• Make it harder for opponents to justify violence
• Create space for dialogue and compromise

How Cities Shape Our Friendliness

This section was a revelation. Architecture isn’t just about buildings - it’s about building communities:

Fortunately, we already know how to build cities that promote contact, because architecture, like all technology, is an extension of ourselves.

Cities That Divide:

• Highways splitting neighborhoods
• Lack of public parks and gathering spaces
• Economic segregation (like Tehran’s rich north/poor south divide)
• Gated communities and fortress-like architecture

Cities That Unite:

• Walkable neighborhoods with mixed-income housing
• Abundant green spaces and public squares
• Community centers and libraries
• Streets designed for people, not just cars

The message is clear: we haven’t changed much since our hunter-gatherer days. We still need face-to-face interaction, diverse perspectives, and safe spaces to build relationships with people unlike ourselves.

Our habitat has changed, but we have not. We are at our most productive when we live in large, cooperative groups. We are at our most innovative when we exchange ideas with people from diverse backgrounds—even those with whom we vehemently disagree. We are at our most tolerant when the architecture of our society facilitates tolerance. In order to maintain a healthy democracy and express the best of human nature, we need to design the spaces we live in so we can meet each other without being afraid, disagree without being disagreeable, and make friends with those least like ourselves.

What I Liked About The Book

• The long list of references. The Author doesn’t talk without evidence. About 28.5 % of the book is taken by the references.
• Small book and rich in content. It is about 288 pages. I really don’t appreciate long books. The amount of bullshit has direct relationship with the number of pages:
• The book is readable by almost everyone. It doesn’t throw anthropological jargon at the audience.

What I Disliked About The Book

Nothing

My Score

10 out of 10

Questions To Ponder Upon

All These questions are answered in the book. I don’t provide answer to make you more eager to read the book :)

• why do we have white sclera?
• Does kindness toward animals really translate into kindness toward others?
• Can’t we just breed humans to be friendlier?

One Last Sentence

Our lives should be measured not by how many enemies we have conquered, but by how many friends we have made. That is the secret to our survival.

References

Survival of the Friendliest

The Millennium Project: The Millennium Project75 is a think tank that ranks the fifteen biggest global challenges every year.

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