Book Summary: Sapiens by Yuval Noah Harari

My Personal Summary

This is a book about the history of humankind.

The Cognitive Revolution began 70,000 years ago in which genetic mutations allowed humans to think in new ways. Fast foward to 12,000 years ago and the agricultural revolution occurred, allowing the explosion of the human population. Then 500 years ago the Scientific Revolution allowed us to build new technologies that created tremendous wealth for humans.

The one aspect that has allowed humans to dominate the Earth has been our ability to believe in myths – money, religion, politics, corporations, etc. – which has allowed us to cooperate in large numbers and basically take over the world and in the process kill many species and use others for our own good such as farm animals.

Capitalism has caused economies around the world to explode and technology has allowed us to improve our living standards and may eventually allow us to become immortal.

Book Notes

Chapter 1: An Animal of No Significance

  • 14 billion years ago, the Big Bang created matter. The study of the universe is known as physics.
  • 300,000 years later, matter and energy coalesced into atoms, which combined into molecules. Thet study of atoms and molecules is called chemistry.
  • 4 billion years ago, molecules combined to form organisms. The study of organisms is called biology.
  • 70,000 years ago, the species homo sapiens formed cultures. The study of the development of cultures is known as history.
  • Three important revolutions shaped the course of history: the Cognitive Revolution kick-started history 70,000 years ago. The Agricultural Revolution sped it up 12,000 years ago. The Scientific Revolution, which started 500 years ago, sped it up even more.
  • Homo Sapiens are just one of six genus in the Homo species. They’re the only surviving humans. We only jumped to the top of the food chain in the last 100,000 years. Fire played a big role in this transition – we could scare away lions and stay warm at night. Fire also enabled cooking of food, which enabled humans to eat more foods since they had to chew less.

Chapter 2: The Tree of Knowledge

  • Genetic mutations caused the Cognitive Revolution about 70,00 years ago, enabling humans to think in new ways.
  • What makes humans unique from other animals is our ability to believe in myths and cooperate in large scales. E.g. religion, states, and companies are all non-existent things – you can’t see them physically, yet because millions of people believe in them it allows us to cooperate at scale. Normally a tribe would be limited at about 150 people, but thanks to our ability to believe in myths we can cooperate into the millions.

Chapter 3: A Day in the Life of Adam and Eve

  • As a human collective, we know far more today than we did thousands of years ago, but foragers as individuals knew far more than any individual modern human since they had to memorize facts about plants, wildlife, animals, temperature patterns, etc. to survive.

Chapter 4: The Flood

  • Humans wiped out nearly every large species of animal wherever they moved – Australia, Americas, etc. They destroyed much of the biodiversity of animals and plants that used to exist.
  • It was easy to wipe out large mammals because they had never seen humans before so they didn’t know that they should be scared of them or view them as predators. Since humans could cooperate well in large groups, humans easily trapped and killed large mammals much larger than them.

Chapter 5: History’s Biggest Fraud: The Agricultural Revolution

  • The Agricultural Revolution lead to a poorer diet, less free time, and a massive drop in quality of life for animals that are now farm animals.
  • The Ag. Rev. is also the reason the human population took off at a rapid pace unseen previously in history.
  • Domesticated cattle and chickens live the most dreadful lives of any species in existence currently.

Chapter 6: Building Pyramids

  • Mythical “orders” or documents are what allow hundreds of millions of humans to cooperate in everday life. The oldest living example is Hammurabi’s Code – a list of laws that governed the ancient Babylonian Empire. The most famous one in existence today is the Constitution of the United States of America.

Chapter 7: Memory Overload

  • Human brains can’t possibly remember every fact they may need to know in modern life, thus documentation and writing was invented.
  • Math and numbers were also invented to help people communicate even more complex ideas like “poverty rates”, “credit scores”, “tax rates”, etc.

Chapter 8: There is no Justice in History

  • For most of human history, men have enjoyed more privilege and power than women, and whites have enjoyed more privilege and power than minorities.

Chapter 9: The Arrow of History

  • As history has gone on, the world has moved more and more towards global unity. There are three main drivers behind this: money, politics, and religion.

Chapter 10: The Scent of Money

  • The rise of larger cities and kingdoms made it possible for people to specialize in different types of work. But this meant that bartering became harder (.e.g I’ll give you 7 apples for a new pair of shoes, but only if you need apples) and thus arose a need for a common currency.
  • “Money is not coins and banknotes. Money is anything that people are willing to use in order to represent systematically the value of other things for the purpose of exchanging goods and services. Money enables people to compare quickly and easily the value of different commodities (such as apples, shoes and divorces), to easily exchange one thing for another, and to store wealth conveniently.”
  • Money isn’t just coins – e.g. prisoners use cigarettes as the common currency.
  • “Christians and Muslims who could not agree on religious beliefts could agree on monetary belief, because whereas religion asks us to believe in something, money asks us to believe that other people believe in something.”

Chapter 11: Imperial Visions

  • Empires further made it possible for larger groups of individuals to follow the same set of laws and practices.

Chapter 12: The Law of Religion

  • There have been countless religions that have popped up over the years. This has been another driving force to unite people.

Chapter 13: The Secret of Success

  • “We study history not to know the future but to widen our horizons, to understand that our present situation is neither natural nor inevitable, and that we consequently have many more possibilities before us than we imagine.”

Chapter 14: The Discovery of Ignorance

  • The scientific revolution that began in the 1500’s has accelerated human technology and civilizations more in the last 500 years than the previous millions of years hitherto.
  • Science is dependent on looking at and understanding data.
  • Statistics is an important field that has emerged in the last 200 years that allows us to understand and take actions based on data.

Chapter 15: The Marriage of Science and Empire

  • Imperialism (conquering other places) and science have a deep history. Often science has enabled imperialism through technology, better ships, weapons, etc. but imperialism also allowed scientists, geographers, botanists, etc. to learn more about distant lands and explore new plants, cultures, ways of living, etc.
  • The Europeans had more of a mentality of “we don’t know what’s out there” and a willingness to admit ignorance and explore the world for answers compared to Asian cultures, which is why Europeans did most of the early exploring and conquering of other lands.
  • Sadly Europeans demolished most civilizations they encountered and wiped out indigenous people or used them as slaves when they arrived in their lands.

Chapter 16: The Capitalist Creed

  • Capitalism is the underlying structure that allowed empires and science to flourish. “Neither modern armies nor university laboratories can be sustained without banks.”
  • The basic idea behind capitalism is this: A contractor deposits $1 million in the bank. An individual then wants to open a bakery but has no money, so they get a $1 million loan from the bank and pay the contractor to make the bakery. Upon getting paid, the contractor deposits another $1m in the bank. Now the contractor has $2m in his bank account, but there’s only actually physically $1m in the bank. This is the magic of credit. The bank believes in the future of the bakery, which enables them to give out a loan. And once the bakery turns a profit, they’ll pay their loan back with interest. And this simple idea of extending credit is what allows modern economies to grow so much. The belief that the future will be better than the past is what enables credit to work. And because everyone believes in this idea, it works.
  • A credit rating is simply the probability that a given individual, institution, or country will pay back their loans.
  • Capitalism does have a dark side – since people want profits, they’ll often ignore bad consequences that occur as a result of seeking profits. E.g. land owners just wanted to profit from sugar cane and other goods, so they used slaves to increase profits. Currently agriculture companies and farms want to increase profits, so they’re currently commiting an animal holocaust.

Chapter 17: The Wheels of Industry

  • Economic growth requires energy and raw materials. Fortunately humans have found new ways and more efficient ways to generate energy over the years, so the idea that we’ll ever run out of energy is actually unlikely.
  • “At heart, the Industrial Revolution has been a revolution in energy conversion.” Every few decades we discover a new energy source.

Chapter 18: A Permanent Revolution

  • The development of nuclear weapons has actually made wars less likely because the threat of nuclear weapons as force would basically mean the end of humanity.

Chapter 19: And They Lived Happily Ever After

  • Humanity has come a long way since the time of foragers, but by most means we’re no happier. Infant mortality and death from disease has gone down, which is good, but in general people’s expectations rise in tandem with their lifestyles so most people aren’t happier because their expectations for quality of life are so high.
  • Buddhism may actually hold the secret to unlocking happiness and lasting peace. The central idea of Buddhism is that suffering arises as a result of craving. The way to end craving is through meditation and through complete focus on the present moment. When you’re present, you don’t crave anything. You just experience life fully.

Chapter 20: The End of Homo Sapiens

  • With the development of bio-engineering, it’s possible that humans may achieve immortality and even turn ourselves into an unrecognizable species. We may even soon develop the ability to bring back Neandrathals and mammoths due to genetic engineering. It’s hard to predict what the future holds.

Leave a Reply

Your email address will not be published. Required fields are marked *