From conquering famine, plague, and war to seeking immortality, happiness, and divinity.
About the Author and the Book
Yuval Noah Harari, an Israeli historian and professor at the Hebrew University of Jerusalem, rose to global prominence with his bestseller Sapiens: A Brief History of Humankind (2014). Building on that work’s broad historical lens, his follow-up, Homo Deus: A Brief History of Tomorrow (2016), turns its gaze toward the future. While Sapiens asked how Homo sapiens came to dominate the world, Homo Deus asks: What will humanity become next?
The book was widely acclaimed, appearing on The New York Times and international bestseller lists, and was named one of Time magazine’s ten best non-fiction books of the year. It has been translated into more than 50 languages and endorsed by global figures such as Barack Obama, Bill Gates, and Mark Zuckerberg. Its influence extended into discussions on AI ethics, futurism, and policy.
However, Homo Deus has also faced significant critique. Scholars have accused it of excessive speculation, a deterministic view of technological progress, and blurring the lines between evidence-based prediction and philosophical conjecture. Historian John Gray criticized it as “a messianic narrative,” while others noted that Harari often compresses complex ideas into pithy generalizations. Still, few deny the book’s intellectual reach or its power to provoke conversation.
Part I: Homo Sapiens Conquers The World
In the first part of Homo Deus, Harari sets the stage for his central thesis: having largely overcome famine, plague, and war, humanity is now poised to pursue new and unprecedented goals—immortality, bliss, and godlike control over life.
“For the first time in history, more people die today from eating too much than from eating too little; more people die from old age than from infectious diseases; and more people commit suicide than are killed by soldiers, terrorists, and criminals combined.”
This shift, he argues, signals the end of the humanist era—a period in which liberal ideology, based on the sanctity of the human individual, provided the dominant moral and political framework. As the 21st century unfolds, we may move toward a post-humanist reality, shaped not by religion or nationalism, but by technology and data.
Chapter 1 – The New Human Agenda
Harari opens by asserting that humanity has historically been obsessed with survival. For millennia, famine, plague, and war were considered natural and inevitable. Today, however, they are increasingly manageable technical problems, rather than unsolvable existential threats.
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Famine: Historically a regular occurrence, especially in agrarian societies, famine is now mostly the result of political mismanagement, not food scarcity. As Harari notes, “There simply is no reason why anyone in the world should die of hunger.”
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Plague: Epidemics once wiped out large portions of the population, but modern medicine, vaccines, and global coordination have drastically reduced their scale and mortality. Even the COVID-19 pandemic, which postdates this book, echoes Harari’s claim that “plague is no longer an uncontrollable natural disaster.”
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War: Once considered a legitimate tool of policy, war—especially between great powers—has become rare. Nuclear deterrence, economic globalization, and interdependence have made large-scale war less rational and less acceptable.
This success, Harari suggests, has created a new moral and political agenda: the pursuit of immortality, happiness, and divinity. These goals, previously the domain of religion, are now within the grasp of scientific and technological innovation.
“Having secured unprecedented levels of prosperity, health, and harmony, and given our past record and current values, humanity’s next targets are likely to be immortality, happiness, and divinity.”
Chapter 2 – The Anthropocene
With nature increasingly under human control, Harari argues that we are now living in the Anthropocene—an epoch defined by human impact on the planet. No longer merely adapting to the environment, Homo sapiens is now an agent of geological change. Species are domesticated or driven to extinction, rivers diverted, climates altered.
At the same time, humans are redesigning life itself. Through genetic engineering, biotechnology, and artificial intelligence, we now alter evolution—not over millennia, but in real time.
“For 4 billion years,” Harari writes, “natural selection was the sole principle that shaped life. Now intelligent design is taking over.”
Harari underscores that these powers are not evenly distributed. A global elite—scientists, governments, and corporations—are the ones who hold the keys to the future. This creates a moral dilemma: who decides what a better human or a better world looks like?
Chapter 3 – The Human Spark
In this chapter, Harari returns to the question of what made Homo sapiens unique in the first place. It wasn’t our physical attributes, but our ability to imagine collective fictions—gods, nations, corporations—that allowed large-scale cooperation. “Sapiens rule the world because they are the only animal that can cooperate flexibly in large numbers.”
However, Harari now introduces a more challenging question: What happens when non-human intelligence can perform tasks better than us—without needing belief, ethics, or consciousness?
As artificial intelligence and machine learning progress, we may find ourselves no longer essential to decision-making processes. Algorithms could govern markets, legal decisions, even emotional relationships.
“As Homo sapiens becomes Homo Deus, we risk becoming irrelevant—not because we fail, but because we succeed.”
In this view, the greatest threat to humanity is not destruction, but obsolescence.
Part II: Homo sapiens Gives Meaning to the World
From gods to individuals to data—how meaning evolved, and how it might collapse
In Part I of Homo Deus, Harari explained how humankind overcame many of its ancient threats—famine, plague, and war—and has set its sights on new ambitions: immortality, happiness, and power. But with this new agenda comes an even deeper question: what gives life meaning?
Part II of the book examines how Homo sapiens constructed meaning systems over time, particularly through the rise of humanism—the idea that the human experience is the ultimate source of truth and value. But Harari warns that this humanist framework, which underpins modern liberal democracies, education systems, and even art, may not survive the 21st century.
Chapter 4 – The Storytellers
Humans, Harari argues, are storytelling animals. Our ability to weave meaning into events—through religion, politics, and myth—is what has allowed civilizations to flourish. Unlike other animals, we don’t just feel emotions; we narrate them.
“Humans think in stories, rather than in facts, numbers or equations, and the simpler the story, the better.”
The humanist revolution—rooted in the Renaissance and Enlightenment—placed the individual human experience at the center of the story. Whereas medieval societies prioritized divine authority, humanist systems replaced this with inner authority: the heart, the conscience, the self.
Art, ethics, and politics became centered on personal authenticity and emotional truth.
“If something feels good—it is good,”
Harari writes, summarizing the humanist credo.
Chapter 5 – The Odd Couple
Harari explores the unlikely alliance between science and humanism, which has shaped much of modern society. While science emphasizes observation and objectivity, humanism is based on subjective feelings and individual experience.
These two systems might seem contradictory, yet for centuries they coexisted. Scientists advanced technologies that improved human life, while humanists justified these efforts as serving human well-being.
But Harari warns that this alliance is fraying. Neuroscience increasingly suggests that feelings are not reliable indicators of truth, but simply biochemical algorithms shaped by evolution. This undermines the foundation of humanist ethics.
“The algorithms that will shape our future do not need to be conscious. They just need to be efficient.”
As artificial intelligence begins to outperform humans in recognizing emotions, driving cars, or diagnosing disease, the assumption that humans are uniquely qualified to make judgments comes under threat.
Chapter 6 – The Modern Covenant
Modernity, Harari explains, was built on a deal: humans would give up traditional religious authority in exchange for technological power and personal freedom. This “modern covenant” promised that if we trust in science, capitalism, and liberalism, we will gain control over our environment—and improve life for all.
This has largely worked. Life expectancy, literacy, and economic prosperity have skyrocketed. But Harari questions whether this success has brought greater happiness.
“Modernity is a surprisingly simple deal. The entire contract can be summarised in a single phrase: humans agree to give up meaning in exchange for power.”
By replacing religious certainties with open-ended growth, modern humans often feel existentially unanchored. The pursuit of constant improvement—economically, emotionally, physically—can become a source of anxiety rather than fulfillment.
Chapter 7 – The Humanist Revolution
Humanism, in its various forms, redefined what it means to be human. Harari distinguishes between three strains of humanism:
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Liberal humanism – emphasizes individual rights and freedom (the dominant ideology in modern democracies).
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Socialist humanism – prioritizes equality and community (inspired by thinkers like Marx).
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Evolutionary humanism – seeks to improve the human race through competition (in its most extreme form, Nazism).
All three ideologies agree that human feelings and experiences are the ultimate source of value, but they differ in how society should be structured to respect or optimize those feelings.
Yet Harari cautions that none of these may survive the 21st century, especially if humans lose their monopoly on intelligence.
“The free individual is just a fictional tale concocted by an assembly of biochemical algorithms.”
If AI can predict our choices, and genetic engineering can reprogram our emotions, the concept of individual autonomy may collapse—making data and algorithms the new sources of authority.
Part III: Homo sapiens Loses Control
From masters of the Earth to obsolete algorithms—what happens when intelligence decouples from consciousness
In the final part of the book, Harari contends that Homo sapiens may not just change in the future—we may become irrelevant. For millennia, intelligence and consciousness have evolved together, bound within human brains. But now, for the first time in history, intelligence is being uncoupled from consciousness. Harari argues that as non-conscious but highly intelligent systems emerge, they may outperform us—not only at physical labor, but at decision-making, creativity, and emotional analysis.
Chapter 8 – The Time Bomb in the Laboratory
Harari opens this section with a chilling paradox: humanity’s greatest successes may contain the seeds of its downfall. The exponential growth of scientific knowledge, particularly in the life sciences and computing, is making it possible to engineer life—including human life.
Breakthroughs in neurotechnology, bioengineering, and machine learning allow us to hack the human body and mind. For example, scientists can already manipulate genetic expression, build synthetic organs, and decode mental states through brain scans.
Harari argues that we may be approaching the end of the Homo sapiens species—not through extinction, but through self-designed evolution.
“Once technology enables us to re-engineer human minds, Homo sapiens will disappear, human history will come to an end, and a completely new kind of process will begin.”
But who decides how to use this power? And to what end?
Chapter 9 – The Great Decoupling
In this chapter, Harari outlines one of the book’s core ideas: the decoupling of intelligence from consciousness. Until recently, only conscious beings (i.e., humans and some animals) could perform complex problem-solving. But now, algorithms can analyze data, predict behavior, and even compose music—without any subjective awareness.
“Intelligence is decoupling from consciousness. What will happen to society, politics, and daily life when non-conscious but highly intelligent algorithms know us better than we know ourselves?”
Harari notes that many human jobs—doctors, lawyers, teachers, even artists—depend not on intuition but on pattern recognition. If algorithms outperform humans at these tasks, our economic and social roles may evaporate. This creates a new class of people: the useless class.
Not unemployed, Harari clarifies, but unemployable—displaced not by cheaper labor, but by better-performing systems.
Chapter 10 – The Ocean of Consciousness
As we build ever more powerful AI systems, Harari revisits the old philosophical question: What is consciousness? Can intelligence exist without subjective experience?
He acknowledges that science has no clear answer. We do not understand why consciousness arises or what its evolutionary value is. Nevertheless, Harari argues, we’re increasingly entrusting decision-making to systems that have no inner life.
“When a thousand people believe in a fictional story for a month, that’s fake news. When a billion people believe it for a thousand years, that’s religion.”
He suggests that many of the fictions we use to define ourselves—identity, soul, free will—may not survive the rise of algorithmic knowledge. And yet we may cling to these stories, even as we hand our agency over to data-driven systems.
Chapter 11 – The Data Religion
The final chapter presents Harari’s most audacious thesis: that dataism may become the world’s next great ideology. If modernity began by worshipping the individual, dataism may conclude that humans are merely data-processing systems, and value lies in optimizing data flows.
“Dataism declares that the universe consists of data flows, and the value of any phenomenon or entity is determined by its contribution to data processing.”
In this view, life’s meaning does not reside in consciousness, love, or God—but in our role in the greater network of information exchange. Dataism could unify science, economics, and art under one framework: increasing the efficiency of data.
Harari compares this shift to past religious revolutions. Just as monotheism replaced animism, and humanism replaced theism, dataism may replace humanism—not with a grand moral vision, but with efficiency and information fidelity.
Final Reflection
In Homo Deus, Harari urges us to confront a future in which our core assumptions—about intelligence, autonomy, ethics, and meaning—may no longer apply. His forecast is neither utopian nor dystopian, but provocatively open-ended. Will we use our technological powers to upgrade humanity—or to make ourselves obsolete?
As he warns:
“We are on the verge of becoming gods. But what will we do with this power? What do we want to become?”
Let’s conclude with a question for discussion—perhaps in your next meditation circle, or in a quiet moment of personal reflection:
Have there been moments in your life when you felt shaped—or even manipulated—by the algorithms around you? How did that awareness affect your sense of freedom, identity, or choice?