Summary of Yuval Harari’s “Sapiens”

Yuval Noah Harari has written a short book¹ that interprets and explains millions of years of human history while also prognosticating about our future as a species. It is ridiculously ambitious, delightfully entertaining, and replete with sweeping generalizations and provocative claims.

Harari begins by explaining that Homo Sapiens (aka Sapiens) is one species in the genus Homo, a genus we share with others like neanderthalensis and erectus. Our ancestors probably interbred with those other species. In fact, many people have up to 6% DNA from neanderthals or erectus (Africans’ DNA apparently shows little cross-breeding with other homo species). What remains certain is that about 50,000 years ago, all the other homo species disappeared, leaving Sapiens.

The Cognitive Revolution

He conjectures that the cognitive demands to socialize in groups drove the growth of the human brain, eventually leading to language and other activities that allowed us to organize more effectively for survival. One of these attributes that emerged from greater socialization and larger brains, was storytelling — the ability to construct imagined realities. Storytelling allowed us to develop beliefs, narratives, and other purely intellectual constructs that furthered our social and organizational capabilities. Harari uses the example of a limited liability corporation — a completely imaginary entity that nevertheless organizes the work of many people, carrying out a mission across time and space because so many people accept the corporation to be as real as a tree or stone. Other animals do not have LLCs but instead live in the tangible, physical world.

Most organisms use the time-tested process of evolution to adapt to their environments. It’s not very efficient or fast, but it is robust because the adaptations are encoded in DNA, which is a stable repository of information. Sapiens bypassed this slow process by enabling mass behavioral changes without going through a painstaking evolutionary, trial-and-error process. By constructing a narrative, a new imagined reality, Sapiens can pivot quickly and adjust to novel circumstances:

“Consider a resident of Berlin, born in 1900 and living to the ripe age of one hundred. She spent her childhood in the Hohenzollern Empire of William II; her adult years in the Weimar Republic, the Nazi Third Reich and Communist East Germany; and she died a citizen of a democratic and reunified Germany. She had managed to be a part of five very different sociopolitical systems, though her DNA remained exactly the same.” (p. 34)

The consequence was that this cognitive revolution enabled the following:

  • Planning and executing complex activities such as hunting big game in groups
  • Organizing into larger groups up to 150; to transmit large quantities of social information
  • Cooperation between increasingly large groups through the use of “stories”, such as religions, companies, nations, and liberal humanism.

Originally, Sapiens were foragers, enjoying a varied diet and having very few possessions, since their lifestyle required constant movement. Because there were relatively small numbers of forager bands, these early Sapiens were able to live off the land’s abundance, generally finding enough to survive without toiling too hard, according to Harari. Yet this idyll seems to have been characterized by war-like violence on a scale that would have made later, to say nothing of modern Sapiens, recoil. Evidence suggests that 4.5% of these forager Sapiens died violent deaths, far higher than people in modern societies even during times of war.

Despite their small numbers, Sapiens spread throughout the Afro-Euro-Asian continents, likely destroying competing species and other large animals. Less than 50,000 years ago, we overcame the sea barrier and penetrated the Australian landmass; in short order, we killed off most of the large mammals on that continent. Similarly, Sapiens crossed into the Americas less than 20,000 years ago and again presided over a mass extinction of other species. Harari says that while other species evolved defenses against natural predators in lockstep as they emerged and slowly evolved, our sudden appearance didn’t allow most species in these new worlds the luxury of gradual evolution. They didn’t even have the instinct to fear this small, weak, naked ape. Thus was the first large extinction during the anthropocene.

The Agricultural Revolution

For most of our 2.5 million years as a species, we contented ourselves with the hunter-gatherer lifestyle. But starting 10,000 years ago, agriculture changed the course of Sapiens’ history. It appears that agriculture emerged independently in 6 different places on earth. But, Harari states that this was not progress: “The Agricultural Revolution certainly enlarged the sum total of food at the disposal of humankind, but the extra food did not translate into a better diet or more leisure. Rather, it translated into population explosions and pampered elites. The average farmer worked harder than the average forager, and got a worse diet in return.” (p. 79)

Agriculture allowed Sapiens to have more copies of itself, but at terrible cost: less leisure, more work, a poorer diet, and probably shorter lifespans. Sensationally, Harari states that wheat actually domesticated man (not the other way around); and as a consequence, it has become an ubiquitous crop throughout the world — a triumph from an evolutionary perspective. But why would Sapiens go along with this? Perhaps it was for religious reasons: for example, to build great temples of worship as at 10,000 year-old Göbekli Teki², foraging tribes appear to have invested generations of effort to build monumental structures for some cultural reason. To engage in such a concerted, long term, costly effort in monumental architecture, the tribes would have to settle down, surrendering their bucolic forager lifestyle, thus necessitating agriculture.

An agricultural civilization of course meant that we had to give up a nomadic way of life and settle into defined areas, where we cleared forests, diverted streams, domesticated animals, built permanent structures, and so on. These early forms of settlement begat the need for more complex social and organizational structures, leading to cities, states, and eventually empires. Sadly, the lowly farmer had to surrender much of his surplus value to the rulers, who often ran nothing more than extortion rackets. Harari summarizes, “this is the essence of the Agricultural Revolution: the ability to keep more people alive under worse conditions.”

Sapiens evolved to cooperate effectively in groups up to 150 individuals. But the power of myth-making allowed far larger organizations to emerge. These binding myths were as varied as Hammurabi’s Code, the American Declaration of Independence, religions, liberal humanism, nationalities, and political ideologies. These myths create an imagined order that is:

  • Embodied in the material world. For example, we build homes, buildings, and other structures that reflect the myths we create, such as physical borders (e.g., walls) to delineate a country or empire.
  • Shapes our desires. For example, we create aspirations for consumer goods that support the dominant myths; in Ancient Egypt those goods might be a great tomb, while in modern day America, it might be a vacation to Europe.
  • Is Intersubjective. For example, the collective belief in the value of the US dollar or a limited liability corporation is a subjective belief that an entire society is invested in.

Harari treats religious belief from animism to polytheism and the large monotheistic religions as elaborate myth-making in service of Sapiens’ need to organize itself into larger and more complex social groups. In this respect, religions are no different from ideologies like Nazism, the US Constitution, or Liberal Humanism: they are stories we tell ourselves. They are also full of contradictions that resist resolution; these stories require repetition and constant reinforcement because they describe an imagined order. By contrast, there’s no need to market to people the idea of gravity; it exists regardless. But imagined orders must be told and retold so that their hold on our intersubjective imagination is maintained.

“Large numbers of strangers can cooperate successfully by believing in common myths. Any large-scale human cooperation — whether a modern state, a medieval church, an ancient city or an archaic tribe — is rooted in common myths that exist only in people’s collective imagination.”

As Sapiens’ societies grew, they increased in complexity, eventually necessitating a form of record keeping that was more persistent than human memory and also more reliable. Thus partial scripts were invented to record mundane accounting activities such as inventories, debts, and other practical information. These scripts were implemented with means as varied as cuneiform on clay tablets (Mesopotamia) or quipus using colored cords of wool or cotton (Inca). Eventually, partial scripts led to full scripts that could represent the spoken language of Sapiens.

One key organizing tool for Sapiens was the creation of hierarchies. Hierarchies led to the distinctions between men and women, slave and master, aristocrat and commoner, and the many levels of caste systems, such as in India. But none of these distinctions are necessary from a biological standpoint. As Harari points out, an ancient Athenian woman could not vote, be a judge, hold government office, pick her spouse, and was owned by her husband or father. A modern Athenian woman can vote, be a judge, hold government office, choose her spouse, and exercise independence. And yet, biologically, the ancient and modern Athenian women are the same. The difference for each of those women is the myth spun by the culture she inhabits.

The Unification of Humankind

Culture is thus a human myth that helps build consensus and unity in large groups of Sapiens. But these cultures are riven with contradictions and opposing myths. Harari gives the example of the a nobleman in the middle ages: in the morning at church he would be exhorted to be humble and eschew material goods; but by the afternoon, in the company of other noblemen, he would aspire to win riches and defend his honor, by shedding blood if necessary. These contradictions are a product of an intersubjective belief in myths and are never fully resolvable. In this sense, the culture wars of 21st century America are just the collision of different founding myths.

He states that “culture tends to argue that it forbids only that which is unnatural. But from a biological perspective, nothing is unnatural. Whatever is possible is by definition also natural. A truly unnatural behaviour, one that goes against the laws of nature, simply cannot exist, so it would need no prohibition.”

But thanks to these cultural myths, three great unifiers of humankind emerged:

  • Money is a way of capturing value and transferring it, without the inefficiency of barter. The need for all parties to trust that store of value unified us, in that even separate cultures would recognize and accept the money of others, even as they may have been at odds with each other. So, for example, Roman coins were accepted outside its empire. “Money is the most universal and most efficient system of mutual trust ever devised.”
  • Empires emerged as supranational or supra-ethnic entities, often starting out with an inspiring imperial culture. It is gradually adopted and modified by its subject people, who eventually demand equal rights to the founding people. As the empire grows and subsumes the groups within it, the imperial culture flourishes and develops.
  • Religion is “a system of human norms and values that is founded on a belief in a superhuman order”. (p. 210) Religions evolved from animism to polytheism to monotheism and dualism. Each of these orders have their logical and other drawbacks; for example, dualism suffers from the Problem of Order, while monotheism addresses order but cannot deal satisfactorily with Evil.

Harari states that we live in a period of Humanist Religions, such as Liberal humanism, that arose from the Enlightenment; Socialist humanism, from Marxist thinking; and, Evolutionary humanism, combining Liberal humanism and the Theory of Evolution. Liberal humanism (e.g., the American experience) posits that humanity is individualistic and is present in each Sapiens. Socialist humanism (e.g., the Soviet Union) states that humanity is collective and exists in the whole of Sapiens. Evolutionary humanism (e.g., Nazism) contends that humanity is mutable and can either degenerate or evolve into a superhuman.

And, he asks, “How do you cause people to believe in an imagined order such as Christianity, democracy or capitalism? First, you never admit that the order is imagined.”

The Scientific Revolution

About 500 years ago, a remarkable process started that paradoxically began by first accepting man’s ignorance about the world; this ignorance was put to good use because we used observations and mathematical tools to dispel some of that ignorance. Once acquired, that knowledge was used to develop new powers, particularly new technologies.

Premodern systems of knowledge assumed that everything important about the world was already known and codified in sources like the Bible. By definition, what wasn’t in those sources like the Koran or Bible was unimportant. The Scientific Revolution turned this practically on its head; it assumed we were ignorant of the most important things and that all knowledge is tentative. Paradoxically, the reward for admitting ignorance was increased power and control over the world, as the fruits of Science were translated into technology. As these technologies changed the world, the idea of inevitable progress seized the human imagination. And, indeed the basic human condition has altered mostly for the better: not only are there far more Sapiens than 500 years ago, most of us live far better lives than their predecessors.

Since the rise of the Scientific Revolution, we have made a tradeoff: we give up certainty in our knowledge (as espoused in religions and other complete belief systems) in exchange for a process that can gradually chip away at that fundamental ignorance. The problem is at any moment what we thought was true could turn up false or at least incomplete. This type of uncertainty is quite difficult for people to deal with. We crave certainty when all we can be assured of is ignorance.

Yet Science does not exist in a vacuum; it requires support and funding from societies, which inevitably sets its priorities. Thus, it partners with ideologies or religions to justify the purpose and societal cost of the research. Two of the most important partnerships are imperialism and capitalism.

The conquest of most of the world by European powers starting in the 16th century is often attributed to a technological advantage they had; but, in fact, they didn’t have a significant edge over the ancient civilizations of India or China (they did however have an advantage over the Aztecs and Incas). What distinguished the European powers was their embrace of ignorance and the desire to overcome it by seeking out distant lands and conquering them.

When the Spaniards encountered the Aztecs and Incas, they brought a rapacious worldview that quickly subjugated those empires and peoples. The Incas could have learned from Cortés’ conquest of the Aztec Empire, but they were insular and weren’t even aware of the Spanish until Pizarro appeared 10 years after the fall of Tenochtitlan and proceeded to use the same playbook to conquer the Incas!

However, conquered peoples eventually adapted, weaving their own myths. By the 20th century, the French, British, Russians,and Americans slowly learned that they could not overawe non-European peoples through force alone, because those peoples adopted an European worldview and engaged their would-be conquerers across many dimensions, including the battlefield, the home front, and international public opinion. Thus, as early as 1950, the peasant army of Mao’s China first routed, then fought to a standstill the most advanced armed forces of the United States.

Nevertheless, the expansion of European empires enriched scientific knowledge which in turn increased the power of the sponsoring empires, creating an escalating, complementary cycle. But without the engine of capitalism, none of this would have been possible, according to Harari.

Prior to 1500, the size of the economy stayed pretty much the same. It didn’t grow except when the population also grew. Generally, people’s beliefs were that the future was not going to be any better than the present so there was no point in investing and deferring consumption. As a result, credit was scarce, since any lender would be skeptical that they could be paid back at all. Gradually, this assumption changed and the view took hold that the economy could grow faster than population. This idea was codified in Adam Smith’s book, The Wealth of Nations, where he posited that increased profits would lead to further investment in people and equipment, and greater increases in profits again.

In earlier periods, like the Medieval, the rich tended to consume whatever income they generated, but now, the rich do the opposite; they tend to save and invest most of their income and wealth. For this virtuous cycle to continue, Science had to deliver the innovations that enabled deferred consumption to turn into greater wealth. In this way, Science and Capitalism were intertwined.

For Capitalism to work in practice, a few more innovations were needed: limited liability companies and capital markets — but also cultural and political institutions that could assure people that their property was secure and that disputes would be resolved in an impartial way. Thus, the Netherlands, then Britain, and the United States arose as great centers of Capitalism.

Today, almost all Sapiens live in an Eurocentric world that descended from erstwhile global empires and engage one another with Capitalist economics and communicate using the language of Science. These developments have allowed an unprecedented number of Sapiens to inhabit the earth at increasing levels of material wealth. But, it doesn’t appear that most of us are really much happier. In fact, it may be that we have regressed in happiness because as material conditions have improved, people’s expectations have also moved in tandem, rendering the attainment of happiness as distant as ever. “One of history’s few iron laws is that luxuries tend to become necessities and to spawn new obligations.” And, he states, “happiness does not really depend on objective conditions of either wealth, health or even community. Rather, it depends on the correlation between objective conditions and subjective expectations.”

As Science advances, Harari speculates it may give rise to bionic, AI-assisted, or genetically engineered humans that transcend our past selves and create a new species, beyond Sapiens. In this way, we become our own myths.


Harari has written a book with broad scope from Mathematics to Economics to Biology, vast sweep from the beginnings of homo sapiens to modern man, and prodigious insight from debunking myths to contextualizing the Nazis to pointing out our biases. It is very well written, with a fast, nearly breathless pace that ties together disparate topics in an effort to fashion a new whole. His disabuse of unifying myths like liberal humanism, religions, the US Declaration of Independence, and other cornerstones of human civilization are clever and make sense in the pragmatic, evidence-oriented view he employs. The spotlight he shines on how myths shape culture and dictate our modern existence is novel and insightful; given this framework, it’s easy to understand why and how fractious modern societies are. Our myths are often in conflict with each other and neither side has a more compelling narrative.

That said, there are some minor and major lapses in the book. On the minor side, his example of “the acceleration of mass i under the influence of gravity, according to the General Theory of Relativity”, looks more like an expression for acceleration alone.

More significantly, his claim (without much evidence) that hunter gatherers were happier than the farmers that succeeded them seems problematic; he admits they probably died violently at higher rates than most farming societies. He assumes they had plenty of free time to socialize, and man being a social animal, they should have been happier.

Harari’s provocative claim that “wheat domesticated Sapiens” is clever, but hardly proven. Certainly, the wild grasses didn’t have any agency in doing so. And what about the other crops and animals that have now multiplied in the Anthropocene? Did they also domesticate Sapiens? More likely, it was a chance partnership that suited the needs of both species. In any event, wheat (and all the other grains, crops and animals that have spread globally with Sapiens) has had to pay a high price: they are largely monocultures, vulnerable to a catastrophic blight.

He also makes generalizations that are glossed over. A central argument is that the demands of socializing drove the growth of the human brain, rather than tool-making or other activities that differentiated early Sapiens. This is an interesting insight, but it seems controversial. Instead, he seems to infer it from primary research by others in the fields of primate communication and socializing.

Another argument that could stand further development is how the Scientific Revolution led to the rise of European powers and their subsequent conquest of most of the world. He attributes this to the acceptance by Europeans of ignorance and their desire to dispel it by venturing far from their native lands. This seems like Romanticism! He doesn’t marshal much evidence for this claim; rather, he moves on to still more tantalizing ideas.

His concept of ignorance needs further exploration; it is a particular kind of ignorance, which accepts the lack of knowledge with the concomitant confidence that it can be overcome. It’s interesting that a perfect understanding or knowledge is not always required to effect change or make useful technologies. For example, spacecraft are sent from the Earth to Mars using Newtonian Celestial Mechanics; there is no need to use the more correct model, Einstein’s General Relativity, since it does not alter the trajectories of the craft in any practical way. (Plus, the mathematics are much easier.)

Harari draws connections that appear less than solid, such as the partnership of Science, Capitalism and European Colonialism. He points out that other civilizations had access to Science and technology and concludes that the main difference was the organizing myth, the desire for knowledge, that allowed the Western world to dominate the globe. And yet there was plenty of closed-minded thinking during this period (e.g., the Inquisition, religious repression, etc.). Could the Indians or Chinese or Africans instead have chanced upon the limited liability corporation, fair ways of adjudicating disputes, and Capitalism, and thus been the ones to break out? Was it just luck that favored the Europeans?

  1. Harari, Yuval N. author. Sapiens: a Brief History of Humankind. New York: Harper, 2015.
  2. By contrast, stonehenge is “only” 2500 years old.

Entrepreneur, technologist, business strategist, history buff, photographer, with a diverse range of interests.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store