Homo Deus

What makes humans the planet’s dominant force? In Homo Deus, Yuval Noah Harari argues that shared fictions—collective imaginations turned into institutions—are the engine of human power. Unlike any other species, you can cooperate flexibly with strangers by believing in the same stories: gods, nations, money, human rights. These stories have built empires, economies and religions, and now they fuel science and technology that aim to turn humans into gods. But each leap in power has come with profound ethical and existential costs.

The rise through storytelling

The Cognitive Revolution, around 70,000 years ago, marks the origin of this ability. You can share myths about things that do not exist outside collective belief—spirits, tribes, corporations—and coordinate thousands or millions through this network of trust. Harari stresses that this “fictional cooperation” distinguishes you from chimpanzees or bees: it’s flexible, not hardwired. The first sculptures, like the Lion-Man from Stadel cave, record this awakening of imagination. It is here that humans become historical agents rather than biological curiosities.

Agriculture and civilization

The Agricultural Revolution transforms storytelling into social order. By domesticating wheat and livestock, you enter a “luxury trap” that multiplies population but erodes wellbeing—bent backs, repetitive labor, malnutrition. Wheat, Harari quips, domesticated you. The same myths that once connected bands—about gods and duties—now legitimate hierarchies and suffering. Farmers serve kings and deities; animals serve humans. Religion and bureaucracy stabilize these arrangements through what Harari calls the Agricultural Deal: obedience exchanged for divine protection and cosmic order.

Empire, writing and the invention of order

Once you write, arithmetic and paperwork extend these fictions across continents. Clay tablets, cuneiform and eventually Aristotle’s logic turn stories into instruments—contracts, titles, tax ledgers. Empires like Rome or Persia rely on them to administer diversity. Religion, money and empire converge as unifying forces: money makes strangers trust one another, universal religions make them share values, and empires build the infrastructure that carries both. Humanity moves toward cultural unity because common myths travel faster than swords.

Science, capitalism and the modern covenant

Modernity begins when science turns ignorance into method. You admit “we do not know” (ignoramus), test by observation and mathematics, and transform doubt into discovery. When this empiricism meets capitalism—the belief in credit and perpetual growth—a new covenant emerges: give up eternal meaning in exchange for material power. This marriage fuels empires, industries, and digital revolutions. But it also replaces gods with humans and humans with markets, creating the paradoxical world you inhabit today: richer, healthier, longer-lived, yet morally and ecologically precarious.

Where it leads

Now that famine, plague and war are largely under control, humanity pursues immortality, happiness and artificial divinity. Biotechnology and artificial intelligence promise to redesign bodies, brains and even consciousness. The story that once gave you dominion over the Earth may soon close its circle—humans remaking evolution itself. Harari’s question for you, the reader, is unsettling: when Homo sapiens becomes able to play god, who decides what god to be?

Seventy millennia ago, the emergence of complex language transformed small ape bands into vast coalitions. Harari emphasizes that the revolution wasn’t about more accurate description but about imagination: the ability to build shared fictions. You can gossip to monitor trust, but only myth lets you unite tribes through invisible symbols—totems, ancestors, spirits, or corporate charters. These fictions scale cooperation beyond Dunbar’s 150-person intimacy limit, allowing strangers to fight, trade and worship together.

The social software of belief

Shared myths act as social software: change the story and you rewrite cooperation. Money works because strangers accept its symbolic value; human rights work because societies collectively believe in them. Harari’s core insight is that fiction, not logic, made humans the ruling species. The lion-man figurine, long-distance trade networks and early seafaring show myth’s power: only a species that imagines non-existent orders could cross oceans and organize mass projects.

The seeds of culture

Foragers lived light but richly. They enjoyed varied diets, short workdays, and deep ecological knowledge. Modern skeletons still bear witness: early hunter-gatherers were taller and healthier than early farmers. Yet these societies were morally plural—sometimes generous, sometimes brutal. The archaeological “silence” on beliefs shows that you live surrounded by lost stories, evidence that imagination outran documentation long before writing existed.

(Note: Anthropologists like Marshall Sahlins later dubbed such groups “the original affluent society,” echoing Harari’s argument that satisfaction does not require surplus, only balance between wants and means.)

Harari turns the usual triumphalist story of agriculture upside down. The Neolithic Revolution, he argues, enriched the species while impoverishing individuals. Wheat, rice and corn domesticated humanity, chaining you to fields and calendars. Populations exploded, diets narrowed, and diseases multiplied in dense settlements. The surplus went to elites, monuments and gods, not to everyday comfort. History’s “biggest fraud” lay in mistaking collective success for personal well-being.

The agricultural deal

Domestication applied not only to plants but to animals and ideas. Millions of cows, pigs and chickens proliferated but endured unprecedented suffering—crates, mutilations and emotional deprivation. Harari calls this an evolutionary mismatch: animals retain wild intelligence and needs even as humans suppress them. Religions justified it through myths of divine order—the Flood covenant, temple economies and ritual sacrifices turning exploitation into piety.

Writing, accounting and bureaucracy

Complex agriculture required calculation. Sumerian scribes invented cuneiform to record barley and taxes, not poetry. Writing externalized memory and birthed bureaucracies that could outlive rulers. From ancient ledgers to modern databases, the pattern persists: administration reshapes reality. Records don’t merely describe—they create incentives and hierarchies. Efficient systems privilege the measurable and push aside unquantifiable values like love or care.

(Note: Max Weber’s analysis of the “iron cage of bureaucracy” echoes Harari’s warning that quantification and control often overtake purpose.)

Empires, markets and religions together compressed countless tribes into one human web. Money played a central role: it translated everything into a language of trust and convertibility. Whether cowries, silver shekels or dollars, currency works because millions believe it will. Harari defines it as the purest imagined order—a fiction everyone treats as real.

From barter to credit

Barter collapses under complexity; money solves it by abstracting value. Once value is abstract, empire follows. The same Roman coins that circulated in Britain and Syria spread law and identity. Corporations extended this logic: they are legal fictions that coordinate strangers through contractual faith. When Armand Peugeot founded Peugeot SA, he didn’t conjure metal plants but belief in a charter—a secular analog of divine creation.

Empire and religion as unifiers

Empires spread these fictions globally. Persian tolerance, Roman law, Islamic caliphates and the British Empire each absorbed vast cultural diversity under common rule. Universal religions complemented them: polytheism’s pluralism yielded to missionary monotheism and finally to secular humanism. The legacy is deep—modern nations, laws and global institutions still speak imperial dialects of unification.

Together, money, empire and religion built a single global conversation where almost any human can trade goods, ideas or genes with any other.

Modernity’s turning point comes when knowledge and faith exchange places. Science begins by declaring ignorance—we don’t know—then builds power from experiment and mathematics. Capitalism funds this curiosity by betting on growth: investors risk money today for a richer tomorrow. Harari calls this the modern covenant: abandon cosmic meaning, gain earthly control.

Ignorance as engine

Francis Bacon redefined knowledge as power, while Newton turned celestial mystery into equations. This new method unites empire and science: explorers like Captain Cook map for both curiosity and colonization. The Great Survey of India and William Jones’ linguistic studies exemplify how imperial data-gathering and scientific classification advanced together. Science justified domination even as it dismantled ignorance.

Credit and perpetual growth

Capitalism’s real magic is confidence in the future. Banks lend more than they own because borrowers will create more. The VOC, East India Company and later stock markets institutionalized this trust, channeling capital into global expansion. Economic faith replaced divine providence. The result was explosive innovation—but also exploitation. The Atlantic slave trade, colonial extraction and environmental degradation were by-products of the same belief in growth and reinvestment.

Industry, energy and new time

Steam engines and fossil fuels turn growth into a permanent state. Factory schedules standardize time; railways synchronize it (Britain adopted Greenwich Time in 1880). The state and market replace kin networks; nationalism and consumerism substitute for tribe. Harari’s insight: modern individuals are liberated but atomized, disciplined by clocks and consumption rather than chiefs or priests.

In short, science and capitalism traded myth for material mastery—yet the cost is meaning itself. As Harari warns, the idols of growth and data risk becoming new gods.

Having dethroned God, modernity crowned your inner voice. Humanism treats feelings as the ultimate authority: truth, beauty and morality all arise within human experience. In politics, the voter knows best; in art, beauty is in the eye of the beholder; in economics, the customer is always right.

Branches of humanism

Harari distinguishes three sects. Liberal humanism makes the individual sacred—the moral core lies inside you. Socialist humanism sanctifies the collective species and equality. Evolutionary humanism shifts reverence to biological fitness and progress—its extreme form, Nazism, worshipped evolution itself. These ideologies waged the twentieth century’s bloody “wars of religion,” culminating in liberalism’s partial victory after 1989.

The scientific challenge

Neuroscience now undermines the idea of a free, unified self. Libet’s and Soon’s experiments show brain signals precede conscious choice; split-brain cases reveal multiple sub-selves. Kahneman’s distinction between the “experiencing” and “narrating” selves shows how memory edits emotion. If inner authority is algorithmic, can feelings remain sacred? Harari uses this dilemma to forecast an impending crisis for liberal humanism: institutions built on authenticity may crumble when algorithms know you better than you know yourself.

(Note: Harari’s challenge echoes philosophers from Spinoza to Dennett who reduce free will to illusion, and suggests liberalism will soon face an empirical test.)

The book’s climax arrives when intelligence outlives consciousness. Harari’s forecast: algorithms—organic or silicon—will soon outperform humans at nearly all recognitive tasks. Once intelligence detaches from feeling, societies may stop needing most people while still pursuing data-driven efficiency. This is the great decoupling.

From servants to sovereign algorithms

AI milestones prove the trend: Deep Blue, Watson, AlphaGo, self-driving cars. Machine learning already prescribes medicine, finances and law. As value concentrates in data and computation, political leverage shifts to those who own them. Harari envisions a triage: an upgraded cognitive elite, an algorithmic priesthood managing power, and a “useless class” excluded from economic necessity.

Dataism as new faith

The new religion—Dataism—worships information flow. It sees the universe as data processing; the moral good is maximizing connectivity. Your health trackers, genome databases and social accounts feed this planetary algorithm. Like old gods, data demands devotion; refusal to share looks like sin. Algorithms transition from oracles to rulers—optimizing traffic today, perhaps governing democracies tomorrow.

Upgrades and inequality

Biotech adds a biological schism. The rich may buy longevity, enhanced cognition or a‑mortality, while the poor remain unenhanced. Humanity could diverge into species—Homo deus and Homo sapiens. Upgrading without empathy risks a future of engineered elites and discarded masses. Harari warns that once biological differences encode power, equality—the moral core of humanism—may vanish permanently.

Ethical last questions

You stand at a frontier where algorithms write laws, medicine rewrites genomes, and autonomy erodes in favor of optimization. The ultimate question, Harari says, is not what you can become, but what you want to want. The fate of consciousness—perhaps the rarest phenomenon in the cosmos—depends on how that question is answered.