PDF Summary:Sapiens, by Yuval Noah Harari

...

2. Homo erectus (“Upright Man”): These humans lived in eastern Asia for almost 2 million years, making them likely to be the longest-living human species ever. (As we’ll see, it’s unlikely that Homo sapiens will be around 2,000 years from now, let alone 2 million.)

3. Homo sapiens (“Wise Man”): Us. Our species of man also evolved in East Africa.

Throughout, the term “Sapiens” refers to our own species while the term “human” refers to all the members of the Homo genus.

Shared Characteristics of Humans

Of the eight known human species, only one survived. Before we discuss how Sapiens became the dominant humans, let’s look at what all the human species had in common.

Characteristic #1: Large Brains

Mammals that are 130 lbs typically have a brain that’s an average of 12 cubic inches. In contrast, the brains of early humans were 36 cubic inches. Today, our average brain size is 73-85 cubic inches, and the brains of Neanderthals were even bigger than ours.

It seems like large brains would give us and our fellow humans an obvious advantage over other animals, but it wasn’t necessarily an asset to early humans.

The Disadvantages of a Big...

...

Even today, most of our communication is gossip, if we define gossip as talking about other people. If we hear from a friend that the banker down the street offers fair interest rates on mortgage loans, we feel comfortable doing business with that banker, even though he’s a stranger. On the flip side, if we hear that the banker is a fraud, we stay away from her. Gossip helps us avoid strangers who may cheat us or be undependable.

Neanderthals probably didn’t have the capability to gossip. Their language was equipped to talk about lions and bison, but not other people. When they couldn’t talk about others, they couldn’t assess the trustworthiness and dependability of strangers. That meant they could only cooperate with the people they knew intimately, family members and close locals.

Because an animal can only know so many other animals intimately, the lack of the ability to gossip kept Neanderthal groups small. Sapiens, on the other hand, could form groups of up to 150 people. They didn’t need to know every group member personally to trust them. In a battle, a small group of Neanderthals was no match for a group of 150 Sapiens.

Ability #3: Fictions

A third...

...

Foragers Had a Good Life

Foragers had many advantages over their descendants.

Short Working Hours

Westerners spend an average of 40-45 hours working a week (and some people in developing countries work up to 80 hours a week). Even modern foragers, who generally live in inhospitable environments, hunt and gather for 35-45 hours a week.

It’s very possible that early foragers spent much less time working to find food and resources. Many of them lived in lands much more fertile than the Kalahari Desert. They also didn’t have the chores that take up our time today, like vacuuming, paying bills, and washing dishes.

Health

There were a couple of reasons foragers were taller and healthier than Sapiens after the Agricultural Revolution.

Varied Diet

Because early foragers might eat berries, snails, and rabbit one day and mushrooms, fruits, and mammoth the next, they were rarely malnourished. They got all the nutrition they needed from the variety in their diets.

Farmers, and the societies that depend on them, tend to rely on calories from a single crop, like wheat or rice. Relying on one food means you’re not getting the variety of nutrients you need to be...

...

Reason #2: Climate change usually affects land and sea creatures equally. But 45,000 years ago, when humans spent far more time on land that navigating the sea, only land animals were affected.

Reason #3: It wasn’t just Australia. Wherever humans went, they left a trail of extinction behind. For example, Sapiens only reached New Zealand about 800 years ago. Within a couple hundred years, most of the local megafauna was gone, as was 60% of local bird species. There are numerous examples like this, making Sapiens in particular “look like an ecological serial killer.”

How Could Humans Cause Such an Ecological Catastrophe?

Reason #1: Although large, these Australian species weren’t hard for humans to kill.

Large animals have long pregnancies and don’t have as many children as smaller species, so they breed slowly. Even if humans only killed a few diprotodons every year, deaths could outnumber births, causing the species’ extinction within a few thousand years.

Also, because large animals had no prior experience with humans, and because humans were small and didn’t look particularly menacing, these animals didn’t run away. They didn’t have time to evolve a fear...

...

For example, agriculture was much harder than foraging and hunting for food, and left farmers more vulnerable to disease and hunger. Farmers also had a less nutritious diet than foragers due to its lack of variety.

Agriculture also led to promotion of disease. All the extra food they grew resulted in a population boom. More people meant closer living quarters, leading to disease epidemics. Child mortality soared.

Most of the agricultural surplus went to the elite, and they probably did live better lives than their ancestors. But the Agricultural Revolution didn’t translate to a better life for most individuals.

We won the game of evolution, which judges our success based on how many of us there are on the planet, but we lost individually. In other words, the Agricultural Revolution allowed more people to survive, but the conditions under which each individual lived were worse.

The Success of Wheat

Wheat is one of the most successful plants ever, but its success happened gradually and was probably not planned consciously by Sapiens.

About 870,000 square miles of the earth are covered by wheat. This is the area of Britain, multiplied by 10.

We like to think...

...

Reason #3: Unlike their nomadic ancestors, farmers could actually do something today to influence events tomorrow. For example, they could sow more seeds, dig another canal, and plant more trees. The responsibility to plant the seeds that wouldn’t yield for decades kept them forever looking forward.

Peasant farmers rarely achieved the security they sought. Surplus went to more and more children, or the elites that lived off them. They always had just enough to survive, perpetually working just to have enough to eat.

The Fiction of the Political Order

Where did the elites come from? Why did they have the power to take the farmers’ surplus and keep them living at the subsistence level?

People evolved to cooperate in small groups. As their way of life changed rapidly, there was no time for Sapiens to evolve the skills of mass cooperation. As groups of people got bigger, they needed some kind of organizing structure, a way to help people work together to divide land, settle disputes, and keep the peace. Organizing so many people involved creating myths that served as the links between previously distinct bands of people. This was the foundation of...

...

The Invention of Writing

The solution was writing. Although today we connect the word “writing” with “literature,” early writing was used to record tax payments, debts, and property ownership, not to write poems and stories. Writing also wasn’t invented to record spoken language. It was invented to fill a gap, to succeed where spoken language failed. It was needed to record data.

The Sumerians invented writing in southern Mesopotamia between 3500 BC and 3000 BC. Eventually, the Sumerians wanted to record more than just mathematical data, so they gradually added signs to their script, which developed into a script capable of representing spoken language. We call it cuneiform.

People who weren’t accountants started writing. Kings used cuneiform to give orders, priests used it to write down oracles, and citizens wrote letters. Also around 2500 BC, the Egyptians developed hieroglyphics. Soon after, societies in China and Central America developed full scripts.

It was only after the spread of full scripts that people started writing histories, dramas, prophecies, and poetry. Works that existed only through the passing down of oral tradition, such as the Hebrew Bible, the...

...

How Hierarchies Are Formed

Imagined societies are generally propped up by three elements: a historical accident, the fear of pollution, and the vicious cycle of discrimination.

Historical Accident: The roots of prejudicial hierarchies often lie in a random occurrence in history rather than biological differences.

Fear of Pollution: Humans are biologically programmed to feel repulsed by people and animals that might carry disease. This is a survival instinct. But although the fear is biologically-based, its historical manipulation and exploitation is based in fiction. If you want to ostracize a group (such as Jews, gays, blacks, or women), tell your society that they’re polluted and could contaminate you if you interact with them.

Vicious Cycle of Discrimination: Once a random historical event that benefits one group and discriminates against another occurs, that hierarchy is perpetuated by the people who benefit from it. This reinforces the prejudices used to justify the system. These prejudices, in turn, help maintain the system, and the cycle continues.

Let’s look at how these three elements perpetuate discrimination in America.

**Example:...

...

Because people resolve a culture’s contradictions in different ways, those contradictions lead to the multitude of varied opinions necessary for a creative, productive culture. A culture’s contradictions are its most telling features.

The Direction of Culture Toward Unity

Due to the attempt to resolve cognitive dissonances, cultures are continually evolving. Is this evolution random?

History has a direction, and it’s toward unity. Speaking generally, over time, many small cultures tend to merge to form fewer, larger, more sophisticated cultures. Despite disintegration at the micro-level throughout history, such as the spread of Latin throughout the world dissolving into many regional and national languages, the overall trend is toward the consolidation of many distinct worlds.

The Merging of Worlds

Today, we have a global culture, but for most of history, the earth was a “galaxy of isolated human worlds.” In 10,000 BC, there were thousands of distinct cultures. But by AD 1450, 90% of the world’s population lived in the “mega-world” of Afro-Asia, in which Asia, Europe, and Africa were connected by culture, politics, and trade. By 1788, the world of...

...

Problem #2: Bartering depends on the other person wanting what you have to offer. If you want to trade your apples for a new pair of shoes and the only shoemaker in town doesn’t like apples, or already has enough apples, you’re out of luck.

Some communities in history, such as the Inca Empire and the Soviet Union, tried to establish a central bartering system where products and services were collected centrally and then redistributed to those who needed them. These attempts were inefficient at best, disastrous at worst.

The Development of Currency

Money is anything that A) systematically represents the value of goods and services, and B) people are willing to use in exchange for goods and services. Money isn’t a material reality. It’s another shared myth that allows us to cooperate with strangers and in large groups.

Money has three benefits over the previous systems based on favors or bartering:

1. It can convert almost anything into almost anything else. Unlike with bartering, you can convert even abstract qualities into money. For example, a discharged soldier can exchange his bravery for knowledge when he uses his military benefits to fund his...

...

Benevolent Imperialism

As discussed in Chapter 9, Sapiens have evolved the survival instinct to distinguish “us” from “them.” For example, the name of Sudan’s Dinka people means “people,” as if members of other tribes aren’t even human. Similarly, the name of Sudan’s Nuer group means “original people” and the name of the Yupik people in Alaska and Siberia means “real people.” We’re programmed to care only about “us,” ourselves and those immediately around us, who share our language, beliefs, and customs.

It’s surprising, then, that since Cyrus the Great of Persia established the first Persian Empire around 550 BC, kings and emperors have claimed to conquer territories and people for their own good. And there was some benefit for conquered people—uniting different nations under one government facilitated the dissemination of ideas, technology, and goods.

It was to the advantage of the ruler to encourage this spread of ideas and goods. For one thing, it made ruling easier. It’s hard to run an empire in which every territory has its own language, currency, and laws. Encouraging trade and the transmission of ideas helped standardize government policies and...

...

Religions that are both universal and missionary appear relatively recently in history. These religions have the power to bolster our imagined social orders and unify humanity on a grand scale.

The History of Religion

Animism

Animism is a belief system in which all objects, animate or inanimate, have a soul. According to these religions, humans must consider the feelings and desires of rocks and mountains as well as plants and other animals.

Most religions of hunter-gatherers were animistic. These religions were local rather than universal. Hunter-gatherers typically didn’t travel far in their lifetimes, so they shaped their religion around their own particular territories. This meant that the religion of one forager band in the Ganges Valley might forbid the cutting down of a fig tree to keep the tree’s spirit from exacting revenge. The religion of a forager band in the Indus Valley might forbid the hunting of white-tailed foxes because once a white-tailed fox had led the band to an area abundant with obsidian.

Because they weren’t universal, these religions weren’t missionary. There was no reason for the Indus band to try to convince the people in the...

...

For the same reasons we can’t explain why history happened the way it did, we can’t predict the future. We can’t know if we’re out of the global economic crisis or if China will become the world’s leading superpower.

Why do we fall for the hindsight fallacy? We like to think that history is deterministic because it means that everything that has happened was supposed to happen. It’s comforting. Conversely, it’s unnerving to realize that all the events leading up to this moment could have easily turned out differently and that it’s only a coincidence that most of us today believe in collective fictions such as capitalism and human rights.

History Is a Level Two Chaotic System

One reason we can’t explain history or predict the future is that history is chaotic—it’s too complex to understand how all the variables interact. Not only is history chaotic, it’s a “level two” chaotic system.

A level one chaotic system is not affected by predictions we make about it. For example, the weather is a level one chaotic system. We can make predictions about the weather tomorrow, but those predictions don’t have the ability to change the weather tomorrow.

A...

...

Man’s acknowledgment of his own ignorance was the breakthrough that launched the Scientific Revolution. This awareness of ignorance leads to experiments that take us closer to knowledge. For instance, today, biologists readily admit that they don’t know how our brains produce consciousness and physicists acknowledge that they don’t know what caused the Big Bang. The acknowledgment of these gaps motivates researchers to fill them.

Before the Scientific Revolution, Sapiens got the majority of their knowledge from their religions. The traditions of Christianity, Islam, and Buddhism, among others, claimed that anything worth knowing was already known. You could find these revelations in the holy texts. Any information missing from these texts was unimportant—If God wanted us to know how spiders weave webs, He would have put it in the Bible.

In contrast, even today’s most established scientific theories would still be debatable if new evidence emerged that contradicted them. Generally, we’re far more open to questioning what we think we know.

Observation and Mathematics

Before around 1500, collecting scientific observations about the world was unnecessary because...

...

Why did it take the East so long to catch up to the West? Just as Easterners hadn’t understood the militaristic importance of gunpowder when they accidentally invented it, Eastern leaders didn’t see how new technologies were going to serve them. While Westerners accepted their ignorance and started to believe in the idea of progress, Eastern rulers clung to their power and strove to maintain the status quo.

In contrast, European nations could more easily follow the lead of countries like England because they shared common values, myths, and sociopolitical structures (more on these, below). Asian empires lacked these common myths. The two ideological advantages that the West had over the East were science and capitalism (discussed in the next chapter). We’ll continue exploring science’s role in empire-building below.

Today, almost all humans dress like Europeans, eat like Europeans, think like Europeans, speak like Europeans, and listen to music influenced by Europeans. We are products of European culture no matter where we live.

Science and Empire, Hand in Hand

Science provided imperialists with many practical advantages: They could navigate the seas with...

...

This optimism about progress in the future is what drives our economic system and without it, there’d be no growth. Until relatively recently, this trust in the future didn’t exist, and this limited the growth of the economy.

Indeed, in the past, money could convert almost anything into almost anything else, but those things had to exist. For instance, money couldn’t represent the resources Mrs. McDoughnut hoped to have in the future, once the bakery started making a profit. In an economy without trust in the future, banks wouldn’t loan Mrs. McDoughnut money. The only way she could build her bakery would be to find a contractor willing to wait to be paid until after the bakery was built and making a profit. As this wouldn’t be likely, Mrs. McDoughnut wouldn’t establish her bakery. If many people faced this problem of resources, the economy would remain stagnant.

Trust in the Future and the Invention of Credit

The modern agreement to represent future (and therefore imaginary) resources with money today is called credit. Credit is founded on the assumption that the future will have more abundant resources than the present.

Loans existed in the pre-modern...

...

But the reliance on animal labor led to reliance on plant growth cycles and the sun. This was a problem. When the sun shone and the wheat grew, peasants could harvest, tax collectors could get their money from the peasants, and newly wealthy soldiers and kings started thinking about war. But when the sun didn’t come out in the winter and the wheat didn’t grow, the actions of the whole community came to a standstill.

Breakthroughs in Converting Energy

The discovery of gunpowder introduced the idea that you could convert heat energy to movement, but this was such an odd concept that it took 600 years for gunpowder to be used widely in artillery.

Another 300 years passed before the invention of the steam engine, which also converted heat to movement, through the pressure of steam. After this, the idea of turning one type of energy into another didn’t seem so foreign. People became obsessed with discovering new ways to harness energy. For example, when physicists realized that the atom stores a lot of energy, they quickly devised ways to release it to make electricity (and bombs). The internal combustion engine turned petroleum, previously used to waterproof roofs...

...

These schedules became the model for almost everything we do in our day-to-day lives, even those things that don’t involve coordinating with other workers.

The railway system played a large part in popularizing the use of timetables. In Britain in 1784, each city had its own local time, dependent on the rise and setting of the sun. Before easy transportation and communication between cities, it didn’t matter that each city ran on its own time. But the development of faster trains in 1830 meant people could get to other cities more easily, and the time discrepancies became an inconvenience. The train companies started making schedules according to Greenwich Observatory time rather than local times. This prompted the first establishment of a national time, in 1880, and Brits had to start living according to an artificial clock rather than the natural time dictated by the position of the sun in the sky.

Today, we do everything according to artificial time, and it’s hard to not know what the time is: it’s on your watch, your phone, your laptop, TV, and the microwave.

Major Change #2: Replacement of Family and Community with State and Market

Traditionally, you lived...

...

For example, we change our clothes every day, so we assume it must have been awful to live as a medieval peasant, who didn’t change her clothes often and went months without washing. But medieval peasants were used to living in unwashed bodies and clothes and didn’t seem to have minded. Daily washing and clothes-changing are modern expectations.

We may be unhappier than our ancestors merely because expectations are so much higher. This is due, in part, to the media and advertisements. They manipulate our expectations and erode our contentment. A teenager living 5,000 years ago judged his appearance against his fellow villagers, most of whom were old and wrinkled or still children. Most teenage boys of the past probably felt pretty good about how they looked. In contrast, today, a teenager is bombarded by images of movie and sports stars on TV, the internet, and billboards. He’s much less likely to feel confident in his appearance because the expectations are higher. We don’t compare ourselves against our ancestors. We compare ourselves against our contemporaries.

The Future of Happiness

As expectations continue to increase, it’s possible our happiness will continue...

...

The Future of Intelligent Design

In the future, intelligent design could replace natural selection in one of three ways (or a combination of the three): biological engineering, cyborg engineering, or inorganic life engineering. We’ll look at each in turn.

Way #1: Biological Engineering

This is when scientists intervene with an organism’s biology to change its physical, behavioral, or emotional characteristics. For example, in the past, we did this through castration: we could make a bull less aggressive or preserve a young boy’s soprano voice by removing his testicles.

Recent examples of biological engineering include:

• Genetically engineering E. coli to function as biofuel and insulin.
• Introducing worm genes into pigs, turning pork’s omega 6 fatty acids into omega 3s, therefore making pork healthier for humans to eat.
• Improving the memories and learning skills of mice.

Researchers are even planning to bring back to life species that are long extinct, including Neanderthals.

But all biological engineering projects are controversial. Religious activists say man shouldn’t “usurp God’s role” by creating new species. Animal rights activists fight...