Sapiens Summary

Author and historian Yuval Noah Harari begins Sapiens by noting that for 2.5 million years, humans lived as insignificant animals on Earth. Around 70,000 years ago, humans suddenly began dominating the planet. Over the course of the book, Harari intends to examine several cultural evolutions in human history, including the Cognitive Revolution (70,000 years ago), the Agricultural Revolution (12,000 years ago), and the Scientific Revolution (500 years ago).

He begins by saying that humanity’s ancestors, Homo sapiens—or, Sapiens—were actually one of at least six human species (including Neanderthals) that all disappeared once Sapiens began settling around the globe.

Harari thinks that 70,000 years ago, a random genetic mutation then enabled Sapiens to suddenly evolve new cognitive capacities. He calls this the Cognitive Revolution. Harari notes that animals in nature can only respond to physical phenomena, but Sapiens learned how to make up fictional ideas and believe in things that aren’t actually in the physical world. He gives the modern example of the car brand Peugeot, which exists as more of an idea than a thing. Thousands of people rally around the idea of Peugeot—to make cars and work for the company. They effectively cooperate because of their shared belief in the Peugeot brand. Harari thinks such “imagined realities” have immense power.

Harari then considers human societies between 70,000 and 12,000 years ago, when humans lived as foragers in the wild. He speculates that foragers lived relatively comfortable and happy lives. He estimates that they only worked around 35 hours a week to gather food, their work was stimulating, they didn’t suffer diseases from living in cramped quarters, and they formed close-knit communities where loneliness was rare. During this time, Sapiens spread around the world, causing widespread animal extinctions wherever they went, including most of Australia’s large marsupials (45,000 years ago) and America’s large mammals (16,000 years ago). He sees humanity as a giant human flood (like the flood in the biblical story of Noah’s ark) that kills off animal species, and he worries about a future in which there’ll be no large mammals left.

When the Agricultural Revolution happened 12,000 years ago, humans began gathering around areas where crops grew in the wild. They soon began planting more crops and forming more permanent settlements around them. Harari thinks life got really miserable for most human beings around this time—they had to spend many more hours doing hard labor to raise crops, they had to raise more children to help with farm labor, they lived in cramped quarters that spread disease, and they shifted from a nutritious diet of wild fruits and meats to limited diets of one grain, which made them malnourished. He also thinks people in farming societies suffered tremendous anxiety about their crops, and they were generally more miserable overall. Harari thinks that all this effort to make life easier—by shifting to farming—ended up making life harder for most of humanity.

According to Harari, humans began cooperating in large numbers because they learned how to make up stories—myths, legends, religions, and social values, or “imagined orders”—and trust others who also believed in the same myths. Such myths are powerful because people act as if they are true, but Harari stresses that they’re never actually true—they’re made up, and they’re not always fair to everyone who believes in them. Once a myth is established, it becomes so entrenched in people’s minds that it’s hard to escape.

Most imagined orders—like the Hindu caste system, racism, and the patriarchy—establish hierarchies: they argue that some people are inherently superior to others, and that everybody must stick to their place in the social pecking order so that society functions in an orderly fashion. Despite these problems, Harari thinks imagined orders work: they make people cooperate with strangers, which makes human societies flourish. He thinks that three imagined orders with global power—that unite people under the same rules—are money, empires, and religions. He thinks many societies hate each other’s values, but they still cooperate by using and exchanging money. To Harari, empires subjugate and kill people, but they also unite people under a common culture, language, and set of social rules. Religions like Christianity and Islam also unite disparate people around the world. Some of the imagined orders that rule the world today include economic systems like capitalism (making, selling, and buying goods to make profits and generate wealth). From Harari’s perspective, the imagined orders that humanity has come up with so far aren’t necessarily the best ones, and there could be better ones out there.

Before the advent of science, Harari argues, people believed that religious texts already contained all the important knowledge and information about the world. But when the Scientific Revolution happened, humans shifted to a mindset of believing they were ignorant about the world and needed to observe it to learn more. Harari thinks people treat scientific theories like they’re true, but really, they’re just theories that tell stories in the language of mathematics.

Harari sees science and empire as closely intertwined. European imperialists who conquered the Americas, Australia, and many parts of Asia between the 1400s and 1800s often claimed to be conducting scientific research. For example, Captain James Cook’s expedition to Australia was an effort to map Venus’s path across the Sun, but he also ended up colonizing Australia for Britain. Harari also thinks science and capitalism are closely connected. When Christopher Columbus wanted to sail westward from Europe to India, he approached many rulers for funding (like an entrepreneur). Queen Isabella of Spain effectively extended credit to Columbus to fund his mission (like a bank or venture capitalist), hoping for a monetary payoff down the line.

Harari thinks about the supposed “progress” in human history since the Agricultural Revolution, and he wonders if it has indeed made humanity happier. It’s true that humans are wealthier and healthier than they’ve ever been, but modern people also have high expectations that their lives will be easy, happy, and fun, and they spend a lot of time disappointed and discontented when life is hard. He decides that ancient humans had lower expectations about life, so they were probably happier. He worries about scientific efforts to extend human life indefinitely, as he just sees a future of anxious, depressed, immortal people.

Harari thinks more about science and the future. Today, Harari says, governments and corporations fund scientific research when they think it will make them money. He worries about research into cyborg insects that can spy behind enemy lines, cross-breeding DNA to create new species, and artificial intelligence. He sees scientific progress as moving forward at an alarming pace, and he’s skeptical about whether such new inventions are actually good for humanity. Harari concludes that humanity has changed dramatically since its foraging days 70,000 years ago—but he’s not sure it’s gotten better. He thinks humanity’s well-being has actually decreased over time, and he concludes that people are more discontent than ever.