Sapiens – Yuval Noah Harari

This is an amazing book about the history of humankind; that takes you on a journey from our hunter-gatherer past to the present day and beyond. Yuval made me feel immensely ignorant and incredibly intelligent simultaneously. I feel way more informed having read this book and find myself referencing it frequently in conversation. I’d recommend it to everyone.

Rating: 9.5/10

View on Amazon here: Sapiens: A Brief History of Humankind.

You can view my other book notes, rating and recommendations on my books page.


The history of humans has been shaped by three revolutions:

  1. Cognitive revolution (70,000 years ago).
  2. Agricultural revolution (12,000 years ago).
  3. Scientific revolution (500 years ago and still going).

Before these three revolutions, humans were no different to other animals on planet earth. We had an equal impact on the environment (minimal) and lived alongside other animals.

At one point in time, at least six types of humans (Homo) lived together on the planet. It is a common fallacy to think of them in a simultaneous manner, one outgrowing the other. No – they lived at the same time in different places around earth.

Two defining human traits (compared to other animals)

  • Bigger brain.
  • Stand upright – freeing our hands to work on other things.

It wasn’t immediately obvious that these two traits would become advantages. Only in the last 100,000 years have they proven to be so. (Before then – it was probably a greater advantage to have huge claws or be more resistant to the cold).

Domestication of fire was important in human history. It allowed us to cook. But it also became a weapon – perhaps the first weapon that could be created and controlled (kind of) at will by an animal.

Through possible reasons of competition for food, or genocide, the other Homo died out, leaving only the Homo Sapiens. Homo Sapien means thinking man in latin.

Cognitive Revolution

Then the Homo Sapien became smarter. This is thought to be through a random mutation in genes. But it allowed us to think in new ways. The first example of this is the development of language.

Human language is interesting for two main reasons. First, it is the most supple. We can communicate an infinite amount of meaning with our words, which allowed us to say more about our surrounding, and potential predators and prey. Second, we could communicate about each other (gossip) which allowed us to create bigger bands/tribes.

Humans could also use language to communicate things that didn’t exist – fiction. Our ability to make things up, tell stories, allowed us to cooperate in large numbers collectively. This became a key human advantage. Note – this is different to other animals in key ways:

  • Ants and Bees can cooperate in large numbers, but only with family and in a defined and rigid way.
  • Wolves and Chimpanzees can cooperate more flexibly, for different tasks, but only in small numbers that they knew intimately.

Sapiens were the first animal to cooperate in larger groups of unfamiliar people. This was because we used language to create shared stories, or myths, that exist only in our collective consciousness, for example; nations, religions and cooperations.

Importantly, these myths can be shared easily (via language) and can be changed. This means Sapiens speed of change was not limited to physical changes (i.e. changes in biology, as per Darwin’s law) but rather the myths we passed on to our children.

These shared collective myths are what we would consider our culture. From this point, history becomes a discussion on how this culture changes rather than any changes to our biology (although this still happens, at a much slower rate). For example, the French Revolution signalled no changes in human biology, but rather a change in ideas (culture) around freedom and so on.

We can think of the relationship of biology and history as so. Biology depicts what humans are capable of doing, given our physical form. History depicts the changes in culture and the actions taken given that wide scope.


Sapiens were hunter-gatherers for a long period of time. It’s believed that some of modern behaviour is derived from the hunter-gatherer past (e.g. we love sugar because when gatherers found ripened fruit – they ate it all quickly before other animals would find it). Whilst its difficult to know exactly how hunter-gatherer tribes lived, some suggestions are:

  • Smallish communities (12-hundreds).
  • All human (apart from dogs, no other animals had been domesticated).
  • Knew each other intimately and rarely mixed with other tribes.
  • They roamed across land as seasons changed (like other animals, were rarely fixed to a place).
  • More forager than hunter (fruits and veg > meat).
  • Also foraged for knowledge; studied animals and plants for signs of season changing and so on.

We consider contemporary humans as far more knowledgeable. Collectively, we know far more about the world now. But as individuals, the hunter-gatherers knew a lot in terms of what they needed to survive (what fruit was good, what terrain was bad, and so on).

In terms of quality of life, hunter-gatherers:

  • Worked few hours to feed whole tribe.
  • Had variety to their day.
  • Had good diet (varied, and no reliance on a single crop.
  • Were not susceptible to break-out diseases (that spread through domesticated animals).

We know little of their religious views, although its thought that they were Animists – a belief that all animals and plants have a spirit. Similarly, we know little of their sociopolitical organisation, although there is a little evidence there was some hierarchy.

Did they live in peace? They probably moved through periods of peace and violence, as we do today.

The main takeaway is that we don’t know much about this hunter-gatherer community, but we do know that it changed dramatically after the agricultural revolution.

When Homo Sapiens travelled across the sea to Australia, it was a huge feat. Crossing sea was something previously only sea animals could do (biology) but humans worked out how to do it.

It was also a distinct time as humans immediately impacted the environment. Of the 25 large marsupials in Australia, humans killed off 23 species. Do we know for sure Sapiens caused this? Some competing idea:

  • Climate change is often blamed – but animals have survived climate change before, yet they died this time.
  • Sea animals survived – because humans still predominantly stayed on land.
  • It happened several times – whenever humans arrived in a new land mass, the ecosystem and food chain was dramatically changed.

Humans still had few tools, so how did we become the predator to much larger animals?

  • Large animals have large birth cycles, so if you begin to hunt a few you prevent the young from being birthed over a few cycles.
  • Humans had the element of surprise; the other animals didn’t know they were harmful as they’d never seen them.
  • Humans used fire to burn down large areas of land making it easier to hunt.
  • Climate change acted as a dual threat to these animals.

The above points can all be discussed, but the main takeaway is that humans significantly impact any ecosystem they enter. (Similar situations happened, animals dying, when we first travelled to America and South America).

Human’s impact on animals can be thought of in three waves:

  1. First wave – when we travelled to new landmasses, affecting the food chains.
  2. Second wave – agriculture (domesticating animals and rearing them for slaughter).
  3. Third wave – occurring now, in oceans (via pollution and hunting).

It’s a common fallacy that in the past humans lived at peace one and together with the environment. This is false. We have always been devastating to the ecosystem around us, even as hunter-gatherers (post-cognitive revolution).

Agricultural Revolution

The agricultural revolution occurred when both crop and animals became domesticated. It happened in several different places around the earth. In some ways, the revolution happened to us, rather than the other way around. When humans stumbled across wheat, we realised it required watering, weeding and ploughing. In a desire for more wheat, humans first settled in an area to farm it.

This change wasn’t necessarily better for humans. On an individual level:

  • Humans became more vulnerable to crop washout.
  • Humans had a less varied diet.
  • Had a more boring lifestyle.
  • Became more susceptible to predators as we were fixed to a location.

But importantly the overall quantity of food being produced shot up massively. This meant humans could sustain much larger groups of people and fueled a huge increase in the population. If we measure the success of a species by the number of that species, humans began to win big.

The revolution was a gradual process. Fields were burned away and seeds planted (at first almost by accident) but then people observed and trialled what could be done better. As more food was produced, more children were had, which in turn meant more food needed to be produced. Initially, child mortality was actually very low but birth rates were so high that the population grew.

The agricultural revolution wasn’t so much planned, and all the consequences weren’t thought out:

  • We didn’t know the population would grow so quick.
  • Or that animals would spread disease.
  • Or we’d become subject to theft and war (over the land).

But humans also couldn’t turn back:

  • As changes happened gradually, over lifetimes, younger generations forgot or never learned how to forage (and didn’t even know we lived another way).
  • The population had grown so quickly that agriculture was now the only way to maintain it.

As humans domesticated animals, like Chickens and Cattle, they also grew in populous. In terms of evolutionary success, they replicated in huge amounts, but to far lesser welfare. The became dependent on humans for food and lives in worsened conditions. Animals were perhaps the biggest victims of the agricultural revolution.

To put the population growth into context. In 10,000 BD there were 5-8m foragers. By 2AD there was 1-2m foragers and about 25m farmers.

Farmers fenced of lands and for the first time had homes and objects. For the first time farmers planned ahead and worried about the future. The nature of harvests, good cycles and bad cycles, meant people begun storing food. Rains or floods caused stress. This new life became the foundation of political systems.

Stories and Myths

As bigger tribes grew, supported by agriculture, towns and cities developed. For the first time, people created myths of gods and joint companies that bound them. Empires broke out in China (Qin dynasty) and Europe (Romans) were armies existed, supported by taxes.

What is an example of a myth? Take the American constitution. It speaks about liberty, freedom and happiness. These ideas only exist in human minds, not biology. So they must have been made up by man.

These myths bind people and have true believers. They are inter-subjective, so even if one person decides to not believe in them, it does not have an impact.

In order for this new society to function, these myths have to be passed down through generations. But societies became increasingly complex, so we had to find ways to externalise these myths (holding them in our brains alone was limited). So humans invented ways of passing information.

This happened through writing. Sumerians and Inca’s both developed scripts that allowed them to record information. At this point, numbers were developed to track food stores and taxes. Many different types of writing sprung up around the world, all in order to record and store information. Retrieval and catalogue of this information were also important (and difficult – storing lots of rock tablets). Society began to invest in scribes who could do this work effectively.

Injustice in our Collective Myths

The collection of myths that govern society is known as an imagined order. These imagined orders were neither fair nor neutral. Often there were marginalised groups (women, blacks, etc). The imagine order often pointed to some divine power or law of nature to justify why it should stand.

The imagine orders did serve a purpose though. They gave people an understanding of how they should react to other people; how they should categorise and treat others. Even back then, the order would often dictate how individuals ended up in society as marginalised groups had less ability to nurture their skills as well as smaller access to opportunities.

It’s interesting to note that the biological differences between different types of humans were very small. So marginalisation of people was caused almost completely by these created myths.

Whilst biological differences do exist between men and woman (who have a womb) much of the difference in treatment of gender is still the result of myths. A rule of thumb is that biology enables whilst culture forbids. Wombs gave women the ability to have children, it was culture that mandated they should get pregnant.

Another interesting discussion is on homosexuality. Biologically, anything that is possible is natural. Some people argue that homosexuality is ‘unnatural’. But biologically it is possible. So, therefore, it must also be natural. And the history of humans is that we can repurpose our biology. Mouths are biologically existent to consumer food. Yet we also use them to speak and kiss – does this make kissing and speaking unnatural?

The history of patriarchy is almost universal in agricultural societies. Some ideas around that:

  • Men’s strength meant they could own physical jobs and control food supply (an advantage for farming).
    • Yet women historically were not excluded from physical work.
    • Men’s strength is only true on averages. There would have been some women who were as strong, yet there didn’t thrive either.
  • Men were more aggressive.
    • This is supported biologically and in the history of war, but aggression isn’t the only requirement for leadership
  • Evolution made men more competitive and women submissive.
    • Yet there are examples were competitive males serve matriarchal societies (in animal and human kingdom).

Unification Of Man

Cultures are constantly in flux. From outside pressures, such as neighbouring cultures or globalisation. But also from internal pressures; changing ideas of people within. They are ridden with contradictions, for example, freedom (to do what we want) but also equality (which by definition limits that in some ways).

Does history have a trend in culture? A direction? Yes – that trend is toward a unity of all people. We used to have many small tribes. Now we have few accepted nation states. And the trend is toward more unity, via globalisation. Cultures are becoming more similar and trade is making nations increasingly connected.

Humans are different to other animals in that we no longer have an us (our tribe) versus them (all other tribes) mentality. We also think about our people as a whole, the human race. This came to be in three major ways:

  • Economic – money and trade.
  • Political – the spread of empires.
  • Religious – the spread of Christianity, Islam and Buddhism.

Economic unification

Post-agriculture, as kingdoms developed and transport networks grew, there was a new opportunity for specialisation. It made sense given that some areas had natural advantages; for example, areas for clay vs rearing cattle vs making wine. But as communities specialised, barter no longer worked and humans invented money.

Money was actually invented in several different regions, to different extents. Coins became prominent, which gave people liquidity to trade. It represented an external value and was underpinned by trust (initially guaranteed by the Church and state).

For example, the Roman Denaris was accepted far and wide as a fair means of trade as it was backed by the Roman Empire.

Money is often thought of as the ‘root of all evil’ but it also represents the greatest trust network. Money transcends race, gender, culture or sexual orientation.

Empirical unification

The spread of empires is remembered mostly with negative connotations. There were often bloody wars and oppression of people.

But they also resulted in investments in art, history, music, language and so on. Much of modern culture has its roots in the empires of old.

Cyrus of Persia was perhaps the first leader who sought to grow his borders, conquer new areas and unify more people. The trend of empires was like that thereafter. In general empires did two things:

  1. Standardise – the new lands they conquered, as it made for the easier running of the empire as a whole.
  2. Spread their culture – which they considered superior, so they thought of themselves as educating and refining the people of the lands they took over.

Empires often absorbed some culture too. This was natural. But life was not easy for the oppressed. Often it took years for people to become fully assimilated.

Whether your opinion of empires is positive or negative, there is no doubt that it has played part in spreading a more unified culture over time.

Religious unification

As societies grew, they became more fragile. Religion became the tool that leaders used to hold them together.

How do we define religion? In this context, they have two criteria:

  • A superhuman being or god.
  • They provide a framework of norms and values.

It’s thought that religions first became popular around agricultural time, with people praying for good harvest and so on. As societies got bigger, people prayed for more things and began developing multiple gods (Polytheist religions). Often there was one more prominent god, from which Monotheist religions formed, where there was only one supreme god. These Monotheist religions were the first to grow more popular (e.g. Christianity in Roman Empire) as believers thought they were following one supreme god. By nature, these single-god religions invoked a desire to spread the name and purge others (as other gods were seen to discredit your own).

Dualism was also popular, with a good god and evil god. In practical terms, Monotheist religions had only one god but inherited some dualistic features (e.g. Satan and hell in Christianity).

More recently, natural-law religions such as Buddhism grew in popularity. These religions have a spiritual leader, but the leader has no power. Rather they believe the world is governed by natural laws – for example, Buddism is governed by the law that it is a human condition to suffer, and suffering is caused by craving.

In general, we view the world as coming more secular. But if we expand the view of natural-law religions to include ideologies such as communism or capitalism, they are as popular as ever. These ideologies still give people norms by which to live by which unify us together.

Scientific Revolution

In the last 500 years, Sapiens have undergone a massive transformation. The population has grown 14X, energy consumption 150X whilst production has grown 240X. Humans have been to the moon. Humans invented medicines. Humans invented world ending weapons.

From 1500AD humans have understood we can develop new powers by investing in science and research. This created a new cycle in politics, resources and research.

Science became the tool which humans used to probe into the unknown, using methods of testing, experimentation and falsification.

In some ways, Science became a modern religion as people used it to explain phenomena in the world.

People also began to understand that science (theory) could be applied practically to create tools (technology). Science had created practical tools in the past, but mostly by accident. For example, gunpowder was created by accident and used for fireworks before it was ever used as a weapon.

The development of science gave way to a new era of progress. Previously, people were not sure progress could be achieved as regardless of our gods there still existed disease, famine and so on. The development of science and technology during the scientific revolution led to the beginnings of less disease, less poor and so on.

But science is costly and therefore requires funding. This means often it is directed with ideological or political backing and has to this point been directed by capitalism and imperialism.

Science and Imperialism

Science was tied to imperialism early on. Science gave empires the advantage they needed to progress and succeed; weapons, infrastructure and medicine. But empires expansion into new lands also gave scientists new resources, terrain and plants to study. It was the Europeans who first matched the two successfully and had the desire to expand to completely new lands, taking with them a team of scientists to gather information and examples for research.

Science was also used in a negative way. Political powers pointed to ‘science’ to prove that they were a superior conquering people. Biologically we can now show this to be incorrect. To some extent, the discussion has changed from biology to culture, with world superpowers now invading countries on the pretence of superior culture and virtues.

Science and Capitalism

The relationship between science and capitalism is a story of growth. Before the scientific revolution, there was no guarantee economies would grow or thrive. Since the scientific revolution and technology, the general trend of economies is to grow year on year.

As people became more confident in economic growth, we developed systems of credit. People began taking funding or loans to fund increased production, further expedition, and so on. This new capitalist creed led to self-perpetuating growth.

Where expeditions to new lands were initially funded by nations, they also began to be funded by individuals.  Companies would be created that investors could by into, funding new journeys. These companies then led to the creating of financial stock markets. Investors who didn’t get a stock in the initial company could buy from other investors (at a profit). At this time Britain became a leading nation, winning the confidence of financiers funding expeditions. The British East Indian company is perhaps one of the best known, and at one point had a fleet of 350,000 mercenaries heading over to colonise modern India.

Capitalism, Empires and politics became linked. Consider the Opium war between China and UK. China’s people became addicted to opium carried by UK companies. As China sought to halt the trade, MPs in the UK who had shares in the company, launched a war against China in the name of free trade. The army became a tool to defend the states capitalist interest.

Free market purists argue that politics need not be involved. But politics (and supporting armies) govern and protect the trust that goes into the system (and safeguards the credit system).

Free market trading is not always fair or ethical. Left to its own devices, it can lead to collusion, unethical business and mistreatment of workers and people (consider slave trade or sex trafficking). The search for profits is unforgiving.

But as with the agricultural revolution, it can be argued that it’s not yet clear if this revolution is a net benefit for all people. Capitalism is also leading to inequality and unhappiness. Capitalists argue:

  • It’s an irreversible process – we can’t move backwards from trade and globalisation.
  • Patience – that in time all people will become abundant.

Another question is of sustainability. This continual growth requires energy and resources, which the planet has in diminishing amounts.

Industry, energy, resources and Consumerism

Counter-intuitively, as humans have used more resources we have also had more resource to exploit. This is because as we fear diminishing resources, we invest in science and research to better harvest resources or create new ones altogether. For example, when the car industry feared decreasing metal stores, they invented plastics and rubber.

The industrial revolution was a key moment as it was the first time humans became good at converting energy (steam engine turned heat into movement). Energy transfer was used in the creation, production and supply of a proliferating number of products.

There is a fear that we will run out of energy resources. But the sun produces enough energy for our consumption many times over. The truer fear is that we do not have the scientific know-how to adequately convert it.

Industrialisation began a wave where science created tractors and fertilizers that moved people from farms and into factories. We nor produce more physical goods and products than ever. And for the capitalist wheel to work, people need to buy them. The myth of consumerism was then developed – the buying and hoarding of more stuff. Perhaps consumerism is best shown in food; we eat more than we need, leading to obesity, which we try to cure through buying diet products. Consumerism and capitalism are opposite sides of the same coin.

How did the industrial revolution change society for the individual?

As humans progress, we continue to mould the world to our needs. But we are also causing huge environmental degradation; killing many plants and animal species. We are also making the world less hospitable for ourselves via global warming and rising sea levels.

Other impacts to lifestyle following science/industry:

  • Treatment of time – previously we rose the at sun and went to sleep at dark. But factories, electricity and light meant work could happen 24 hours a day. Scheduling became important and we all moved towards a shared time system (GMT) over local times.
  • Urbanisation.
  • Rising middle class.
  • The demise of the family unit – we used to rely on family to support us financially in youth and old age but now state performs this function.
  • Community – close-knit communities have been replaced by brand lead communities. People identify closer to clubs like Manchester United than they do their local community.

The most significant commonality in the last 200 years is continuous change.

A major change is that for the first time in history war does not seem likely. Why is this so?

  • War is more expensive – weapons are more potent so the cost of life far more significant.
  • War is less profitable – economies have moved to intellectual capital, so you cant ravage new lands for their resource (as effectively).
  • Peace is more profitable – via trade and investment.
  • Political pacifists – for the first time most heads of state are anti-war.


Homo Sapiens have progressed significantly through these three revolutions, but are we any happier?

Positive view – As a whole, we are less susceptible to death, wealthier, more abundant, have more opportunities…

Negative view – But we also face more inequality and moved away from a hunter-gatherer lifestyle that at an individual level was perfectly fine

Mixed view – In the overall span of humankind, the Scientific Revolution (which signalled most recent progress) is still quite recent, and we are only now learning how to harness and use these tools for the benefit of all

It’s difficult to support fully any of the above, as we have been inadequate at measuring happiness over time. What studies have shown us so far is:

  1. Wealth makes us happier initially, but then makes no difference – There is some point of money that makes us comfortable but after that no happiness-add
  2. Illness effects happiness when it’s deteriorating – But once we reach a stable level of health (whether it’s good or bad) it no longer affect our happiness
  3. Family and community effect happiness – In particular, a good marriage has been shown to make people happier

So given these three factors, we might argue that increased human wealth has made us happier (1) but the diminishing community and family ties have decreased happiness (3).

But perhaps an even bigger finding is that happiness is less related to these factors, but can be prescribed more to a difference between our expectations and our reality (which philosophers have long thought). In this light, we can consider the impact that mass media and social networks have on our happiness as they more easily allow to compare ourselves to loftier expectations.

The Future of Sapiens

Sapiens may be the first species to transcend the barriers of our biological body. We are the first species capable of altering ourselves through science. This happens in three forms:

  1. Biological engineering – We have altered our bodies for years (e.g. castrating) but now we are far more skilled at it and can do so at the genetic level. This brings on a host of ethical questions. Effectively we are capable of evolving.
  2. Cyborgs – We already use tools to alter our natural selves, such as reading glasses and pacemakers. But now we can create bionic limbs. Whilst bionic limbs may be seen as inadequate replacements now, in the future they may have advantages; like extra strength or control from a distance via remote.
  3. Un-organic life – For example a computer program that stores memories or functions as a brain.

These ideas indicate that humans are capable of creating a change that could change the definition of what we even call human. This is likely to be a dramatic shift.
