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Homo deus: Book Review

Homo Deus: A Brief History of Tomorrow (2016), Harari, another provocative Harari book, with things to contemplate, reconsider, expand my knowledge or challenge. This will be a long review. I put off reading the book, thinking focusing on the future is not the role of historians, but Harari is not the typical historian. He likes to make categorical statements, whether well supported or not. This can be aggravating, but also makes for great quotes, some of which are listed next. His basic thesis is humans now want to turn Homo sapiens to Home deus, upgrading people to gods, including a bid for immortality—death is now a technical problem to solve.


“From the Stone Age to the age of steam, and from the Arctic to the Sahara, every person on earth knew that at any moment the neighbors might invade their territory, defeat their army, slaughter their people and occupy their land. … Sugar is now more dangerous that gunpowder” (p. 14-5).


The most common reaction of the human mind to achievement is not satisfaction, but craving for more. Humans are always on the lookout for something better, bigger, tastier. … Success breeds ambition” (p. 20).

“Modern medicine hasn’t extended our natural life span by a single year. Its great achievement has been to save us from premature death” (p. 27).


This is the best reason to learn history: not in order to predict the future, but to free yourself of the past and imagine alternative destinies” (p. 65).


The crucial factor in our conquest of the world was our ability to connect many humans to one another” (p. 132).

“As long as all Sapiens living in a particular locality believe in the same stories, they all follow the same rules” (p. 143).

“Fictions enable us to cooperate better. The price we pay is that the same fictions also determine the goals of our cooperation, so we may have very elaborate systems of cooperation, which are harnesses to serve fictional aims and interests” (p. 174).


History isn’t a single narrative, but thousands of alternative narratives. Whenever we choose to tell one, we are also choosing to silence others” (p. 176). “Without commonly accepted stories about things like money, states or corporations, no complex human society can function. … Stories are just tools. They should not become our goals or our yardsticks” (p. 177).


“The greatest scientific discovery was the discovery of ignorance” (p. 213).


There is no justice in history. When disaster strikes, the poor almost always suffer far more than the rich, even if the rich caused the tragedy in the first place” (p. 215). “Greed comes easily to humans. Capitalism has thus sanctified a voracious and chaotic system that grows by leaps and bounds, without anyone understanding what is happening and whither we are rushing” (p. 219). “The market’s hand is not only invisible, it is also blind, and by itself could never have saved human society” (p. 220).


Chapter 1: The New Human Agenda. “The same three problems preoccupied the people of twentieth-century China, medieval India and of ancient Egypt. Famine, plague and war” (p. 1). They’re still around, but now manageable. Dying has changed: from infectious disease, starvation and soldiers to overeating and old age. Today, biotechnology and information technology are keys to the future. Pandemics are still a big deal [he wrote this in 2016]: HIV, Ebola, SARS. Battle with China now means cooperating with hi-tech giants—"still power-hungry governments and greedy corporations” (p. 16). Cyber warfare is likely and can destabilize the world; “logic bombs” may be crammed into networks everywhere. Terrorism is more show as a violence spectacle.


Happiness is the purpose of life according to Epicurus [utilitarians have this view]. This is now a “collective project.” Economists are more focused on GDP growth. However, governments make major investments in sewage, water, education, healthcare and so on—the state is to serve people. Happiness depends on expectations rather than on objective conditions. Improving conditions lead to greater expectations. On the other hand, science says happiness depends on biochemicals. Buddha said pursuing pleasure leads to suffering, perhaps similar to biochemical view.


Human upgrades can be bio-engineering, cyborgs, or non-organic. Think “brain-computer interfaces, nano-robots, or artificial intelligence” (p. 49). What is the difference between healing and upgrading? Plastic surgery followed World War I, after facial injuries—then “upgrades.”


“Capitalists in countries such as Britain and France strove to better the lot of the workers, strengthen their national consciousness and integrate them into the political system” (p. 58). “This is the paradox of historical knowledge. Knowledge that does not change behavior is useless. But knowledge that changes behavior quickly loses its relevance. The more data we have and the better we understand history, the faster history alters its course, and the faster our knowledge becomes outdated” (p. 58). “Each and every one of us has been born into a given historical reality, ruled by particular norms and values, and managed by a unique economic and political system. … The new history will explain that our present system is neither natural nor eternal. Only a string of chance events created the unjust world we know today” (p. 59-60).


Part I: Homo sapiens Conquers the World


Chapter 2: The Anthropocene. Harari calls the last 70,000 years the Anthropocene epoch, the age of dominant humans [technically, we’re in the Holocene for 11,700 years, from the last major ice age]. The dating at 70,000 years is questionable, the assumption that humans changed then (e.g., creating language). He characterizes emotions as biochemical algorithms needed for survival, with an algorithm as a “methodical set of steps that can be used to make calculations, resolve problems and reach decisions” (p. 83). [The concept of a “biochemical algorithm” is in the science literature, but does not seem to be widely adopted as a biological principle; I’m still skeptical.] Harari defines algorithm broadly.


Early 20th century psychologists opposed hugs and kisses for kids: it would “spoil them” [explaining much of my early childhood]. Then Harry Harlow separated infant monkeys from their mothers and gave them a choice of a dummy fitted with a milk bottle and a cloth-covered dummy monkey (this was in the 1930s). The infants went straight for the cloth money and clung to it. Mammals need emotional bonds (Harlow’s contact comfort theory). Blankets work for human children too.


“The Agricultural Revolution was both an economic and a religious revolution” (p. 95). Theist religions started as agricultural enterprises, like shepherds in the Old Testament with a focus on farming and village life. Harari descried the Jerusalem temple as “a cross between a slaughterhouse and a barbecue joint … [with] a never-ending stream of sheep, goats, chickens … which were sacrifices at the god’s altar and then cooked and eaten. … justified the agricultural economy through new cosmological myths” (p. 91). People have a soul, but animals don’t in this cosmology and can be destroyed for the crimes of people.


“Whereas the Agricultural Revolution gave rise to theist religions, the Scientific Revolution gave birth to humanist religions. Scientific Revolution gave birth to humanist religions” (p. 98).


Chapter 3: The Human Spark. “According to a 2012 Gallup survey, only 15% of Americans think that Homo sapiens evolved through natural selection alone” (p. 103); 32% that God orchestrated the events, 46% a biblical interpretation. Survival of the fittest is a simple idea, unlike relatively and quantum mechanics. It’s hard to accept the “soul” and evolution—DNA as the heart of creation. “Every subjective experience has two fundamental characteristics: sensation and desire. Robots and computers have no consciousness. … Sensations and emotions are biochemical data-processing algorithms” (p. 107). The biochemical reactions that create pain, anger and love are unknown. Scientists can only pinpoint brain locations. Somehow electric brain signals create streams of consciousness. “Consciousness is the biologically useless byproduct of certain brain processes” (p. 117). [Brain function as “mental pollution?”] Turning Test: can a computer simulate a person? A key point: “No known algorithm requires consciousness in order to function” (p. 122). Clever Hans, the German horse; solving math problems with hoof (by monitoring the human).


People can cooperate in large numbers. Flexibility is key (compare to bees, which also are cooperative). Ceausescu fell in Romania, after a 40-year dictatorship dominated by state news media and other major groups. While given a speech, someone in the crowd booed, then others, then everyone, then the revolution. Too bad the rioters did not know how to organize. That fell to political players, really a wing of the Communist Party. Assets were privatized, selling at bargain prices to ex-communists. Ditto, Egypt after Mubarak. Only major organizations were the army and Muslim Brotherhood.


Ultimatum Game: two players to split a pot of money. First player divides the money; second say accept or reject. Most players reject low offers as unfair. Most kingdoms in history were unequal, but stable and efficient. Importance of threats and promises for big cooperative networks.


Objective realities (things exist independently of our beliefs) and subjective realities (depends on personal beliefs). Money has no objective value. In 1991 leaders of Russia and other satellites dissolved the USSR. So much for that story.


Part II: Homo sapiens Give Meaning to the World.


Chapter 4: The Storytellers. “Humans think they make history, but history actually revolves around the web of stories” (p. 155); real pharaoh versus imagined pharaoh. Cognitive Revolution of 70,000 years ago, humans starting using their imaginations. [Cognitive Revolution usually associated with development in computers and other fields in the 1950s. Humans did use symbolic arts thousands of years ago, associated with “modern cognition.” Could be genetic mutation sometime; not a definitive concept.]


“It is the algorithm as a whole that makes the important decisions. This is the essence of bureaucracy” (p. 160). Writing uses abstract symbols, making is easier to believe in fictional entities. Aristides de Sousa Mendes, Portuguese consul in Bordeaux issued 30,000 visas to French Jews fleeing the Nazis, although his orders were not to. The Portuguese still honored the visas and de Sousa saved 30,000 lives—the bureaucracy. Mao issued the Great Leap Forward in the 1950s to force communal farming to increase surpluses. Of course, just the opposite happened. But bureaucrats lied up the system and farm products were sold; millions starved in China’s worst famine. Similar result in Tanzania when farmers forced onto collective farms. Result: 90% of farmers forced on collective farms produced 5% of the farm product.


As bureaucracies accumulate power, they become immune to their own mistakes. Instead of changing their stories to fit reality, they can change reality to fit their stories” (p. 167). Bureaucratic can explain accumulated myths from ancient civilizations, beginning with taxes, farm fields, and granaries. Priests and nobles gained to claim more wealth for gods and kings, then build it into myths of reality” (p. 170).


Chapter 5: The Odd Couple. “Blind faith in these stories meant that human efforts frequently focused on increasing the glory of fictional entities” (p. 179). Religion is defined by “social function” … Religion is any all-encompassing story that confers superhuman legitimacy on human laws, norms and values. It legitimizes human social structures by arguing that they reflect superhuman laws. Religion asserts that we humans are subject to a system of moral laws that we did not invent and that we cannot change” (p. 182). “Spirituality is a journey. … Spiritual journeys take people in mysterious ways towards unknown destinations” (p. 184). “Religions seek to cement the worldly order whereas spirituality seeks to escape it” (p. 186). “Luther wanted answers to the existential questions of life, and refused to settle for the rites, rituals and deals offered by the Church” (p. 186).


“Scientists study how the world functions, but there is no scientific method for determining how humans ought to behave. … Science studies facts, religion speaks about values. … Religion cannot provide us with any practical guidance unless it makes some factual claims too, and here it may well collide with science” (p. 189-90).

“Religious stories almost always include three parts: 1. Ethical judgments, such as ‘human life is sacred.’ 2. Factual statements. 3. A conflation of the ethical judgments with factual statements, resulting in practical guidelines” (p. 191). “Constantine’s Donation,” giving the pope dominion over Europe, was a forgery.


“Judaism was not a scripture-based religion at all. Rather, it was a typical Iron Age cult. … It had elaborate temple ritual, most of which involved sacrificing animals to a jealous sky god” (p. 195). A religious elite formed during the Second Temple period, under Greek and Persian influences. Scholars were rabbis and they compiled the “Bible.” The Temple was destroyed by Rome, resulting in the rabbis’ book. “Religions have the nagging tendency to turn factual statements into ethical judgments” (p. 196). Sam Harris “thinks that all humans share a single supreme value—minimizing suffering and maximizing happiness—and therefore all ethical debates are factual arguments concerning the most efficient way to maximize happiness” (p. 197).


“We often associate science with the values of secularism and tolerance. … Europe in the days of Columbus, Copernicus, and Newton had the highest concentration of religious fanatics in the world, and the lowest level of tolerance” (p. 198). Tolerance existed in the Muslim world at the time.


“Neither science nor religion care that much about the truth, hence they can compromise, coexist and even cooperate. Religion is interested above all in order. It aims to create and maintain the social structure. … As collective institutions, science and religion prefer order and power over truth” (p. 199). [These statements are difficult to reconcile.]


Chapter 6: The Modern Covenant. “The cosmic plan gave meaning to human life, but also restricted human power. … To the best of our understanding, the universe is a blind and purposeless process” (p. 200-1).

Growth is essential to economists and politicians to consume more and raise the standard of living. Without growth it’s a zero-sum game. [Japan is an exception.] Presumably the growth produces a prosperous middle class and democracy. Capitalism ties into this, in part by investing profits to increase growth. Growth requires resources (materials, energy, and knowledge—only knowledge is a growing resource—e.g., nanotechnology, genetic engineering and artificial intelligence), one driver for European imperialism. The big problem is ecological collapse.

Chapter 7: The Humanist Revolution. “It is impossible to sustain order without meaning. The great political, artistic and religious project of modernity has been to find a meaning to life that is not rooted in some great cosmic plan. … In 1300 people of London: only God could create and define goodness, righteousness and beauty … The antidote to a meaningless and lawless existence was provided by humanism … [which] expects humans to give meaning to the cosmos” (p. 222-3). Psychology diagnoses the “ailments of life, not the meaning of life” (p. 225).


Knowledge=Scripture x logic (medieval Europe). Scientific Revolution: knowledge=empirical data x mathematics (but scientific formula does not deal with value and meaning). Humanism: knowledge=experience x sensitivity, where experience has sensations, emotions and thoughts. Chinese philosophy: the world is sustained by opposing but complementary forces: yin and yang. Yang provides power, yin meaning and ethical judgments. Today it’s reason and emotion (p. 240). Medieval chivalric romances had heroic deeds, not feelings or inner change. Humanists focus on experiences and feelings; consider Joyce’s Ulysses.


“Humanism split into three main branches. The orthodox branch holds that each human being is a unique individual possessing a distinctive inner voice and a never-to-be-repeated series of experiences. … Due to this emphasis on liberty, the orthodox branch of humanism is known as ‘liberal humanism’ or simply ‘liberalism’” (p. 249). [This is independent of political liberalism.]


“Liberal economics maintains that the customer is always right. … It sprouted two very different offshoots: socialist humanism, which encompassed a plethora of socialist and communist movements, and evolutionary humanism, whose most famous advocates were the Nazis. … Neither believed in any transcendental power (p. 249). “Democratic elections usually work only within populations that have some prior common bond” (p. 251). Under socialist humanism needs a group (social) focus. Mao or Lenin would say: “Individual self-exploration is an indulgent bourgeois vice … that reflect upbringing and social surroundings” and depend on class. … The rich are taught to disrespect the poor, while the poor are taught to disrespect their true interests” (p. 253). Collective institutions are required.


Evolutionary humanism starts with Darwin and includes conflict as part of survival of the fittest—who should oppress inferior humans; using war is a valid natural selection strategy. Hitler is thus an extreme version. Socialists criticize liberalism hides exploitative and racist systems, safeguarding property and privilege.


Liberal democracies were successful during much of the post-World War II period, but with successes and failures. Liberalism won when the Cold War ended in 1991. Most countries provide education, health and welfare services, even with individual liberties and belief in voters and customers. “As of 2016 there is no serious alternative to the liberal package of individualism, human rights, democracy, and a free market” (p. 269). China, on the other hand, is an economic giant but neither a free market nor democracy. “Socialism failed to keep up with new technology” (p. 275).

“The Catholic Church established medieval Europe’s most sophisticated administration system, and pioneered the use of archives, catalogues, timetables, and other techniques of data processing. … The Church established Europe’s first economic corporations—the monasteries—which for 1,000 years spearheaded the European economy and introduced advanced agricultural and administrative methods” (p. 276); including clocks, schools and universities.

“A humanist civilization will want to maximize human lifespans, human happiness and human power” (p. 279).


Part III: Home sapiens Loses Control


Chapter 8: The Time Bomb in the Laboratory. “Liberals value individual liberty so much because they believe that humans have free will” (p. 283). Harari challenges this based on science, because are biological activity follows physical and chemical laws of reality; e.g., “electrochemical brain processes are either deterministic or random or a combination of both. … If humans are free, how could natural selection have shaped them? … All the choices animals make reflect their genetic code. … If by ‘free will’ we mean the ability to act according to our desires—then yes, humans have free will. … The question is whether they can choose their desires in the first place. … The process might be deterministic or random, but not free” (p. 284-5).


“A robo-rat is a run-of-the-mill rat with a twist: scientists have implanted electrodes into the sensory and reward areas in the rat’s brain. This enables the scientists to maneuver the rat by remote control” (p. 288). This can be used on humans with ‘transcranial direct current stimulators.’ Of course, it’s the military experimenting with them using helmets to increase performance. Journalist Sally Adee visited a testing facility and used a battlefield simulator with the transcranial helmet. Without it she was scared, make mistakes and did poorly. With the helmet she had total focus, was not scared and killed all the virtual terrorists. She stated: “My brain without self-doubt was a revelation” (p. 291). She wanted to back and do it again.


He reviewed a Kahneman experiment, where volunteers were asked to keep their hands in ice water for a minute. Next, a minute in ice water, then 30 seconds with the water slightly warmed up. For the third, they could choose which one and 80% picked the longer one—with the pain lasting longer, but the end was less painful. Kahneman differentiated between the experiencing self and the narrating self—the one we remember (we don’t remember the experiencing self). In this case, the second experiment was viewed as less painful—the “peak-end rule.” He thinks this includes child birth; no sane woman should want to go through with it a second time, but endorphins create a feeling of relief after the fact—it becomes a positive memory.


“The more sacrifices we make for an imaginary story, the more tenaciously we hold on to it, including ‘our boys didn’t die in vain’ syndrome” (p. 302).


Chapter 9: The Great Decoupling. “Liberals uphold free markets and democratic elections because they believe that every human is a uniquely valuable individual, whose free choices are the ultimate source of authority” (p. 309). However, humans may lose their economic and military usefulness, humans can be effective collectively, and some individuals have value. Harari states that women got rights because of their value in total wars. Thanks to sophisticated technology, humans are less important. Giving them political rights may pay no economic dividends. Intelligence seems to be what counts, but not consciousness. Humans as the “useless class.”


“Lying involves different brain areas from those used in telling the truth” (p. 317). Historically, three market sectors: agriculture, industry, and service. Now, the service industry is growing (only 2% in agriculture and 20% in industry). To date, new professions replaced old ones. David Cope created Experiments in Musical Intelligence, with a computer program (later version named Annie) composing thousands of Bach-style chorales in a day. Various repetitive jobs replaced by algorithms, like telemarketers. Only some are safe, like archeologists. Will there be new jobs that people outperform algorithms?


Google Baseline Study on human health to build the “perfect health profile.” Self-deceptions (narrating self, no peak-end rule) will not fool Google. “Liberalism sanctifies the narrating self” (p. 343)—the former best system. The problem with peak-end rule is extreme incidents remembered rather than majority of events. “Liberalism can coexist with socio-economic gaps. … Liberalism still presupposes that all human beings have equal value and authority” (p. 351). Social inequality shouldn’t matter. Note lower birth rates in developed countries, with more emphasis on education.

Chapter 10: The Ocean of Consciousness. “New techno-religions may conquer the world by promising salvation through algorithms and genes. … Homo deus will retain some essential human features, but will also enjoy upgraded physical and mental abilities” (p. 356-7); perhaps a second cognitive revolution. [Or it started in the 1950s as various cognitive scientists have said.] Consider the spectrum; humans see light in wavelengths between 400-700 nanometers. Sight and mental states could be vastly expanded. Bats view the world through echo-patterns. Whales can hear one another for hundreds of miles. “Liberal humanism makes techono-humanism and medicine increasingly focused on upgrading the healthy rather than healing the sick” (p. 364). Positive psychology can study “super-normative mental states.” “Techno-humanism expects our desires to choose which mental abilities to develop and thereby determine the shape of future minds” (p. 368).


Chapter 11: The Data Religion. “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. … The life sciences have come to see organisms as biochemical algorithms” (p. 372). Think Turing Machine. [There are technical papers on dataism, but it doesn’t seem to be a mainstream idea.] Dataism applies math laws to computer and biochemical algorithms. [According to Google, dataism is a philosophy based on Big Data introduced by David Brooks based on increased complexity, but popularized by Harari with his own definition. I agree that Big Data if important, but a technical issue.] Harari describes it as: “a single overarching theory that unifies all the scientific disciplines from musicology through economics to biology” (p. 372).


The economy gathers data about wants and needs and turns this into decisions. “According to this view, free-market capitalism and state-controlled communism …are, in essence, competing data-processing systems. Capitalism uses distributed processing, whereas communism relies on centralized processing. … The stock market is the fastest and most efficient data-processing system” (p. 374). Government could be considered an “overly centralized data-processing system” (p. 375). “No central processing unit monopolizes all the data on the London bread supply. The information flows freely among millions of consumers and producers, bakers and tycoons, farmers and scientists” (p. 377).


Democracies and dictatorship also competing systems, data processing systems in Harari’s perspective. Centralized processing had the edge in some circumstances, perhaps ancient Rome. Systems have to be efficient given the available technology. “Technical revolutions now outpace political processes” (p. 378)—the government tortoise versus the technical hare. The Internet is free and lawless, creating global risks. “Putin’s aspirations seem confined to rebuilding the old Soviet bloc, or the even older tsarist empire. Meanwhile in the USA paranoid Republicans have accused Barack Obama of being a ruthless despot hatching conspiracies to destroy the foundations of America. … Government has become mere administration. … Conspiracy theories never work, because they underestimate the complexity of the system” (p. 381). People with narrow aims, like billionaires, can flourish.


Think of humans as processors, using a greater variety and connections, and more freedom of movement. Harari history was the cognitive revolution, agricultural revolution, writing and money, and finally globalism information beginning with Columbus. The supreme value is “information flow,” linking everyone with information freedom. Under Harari, the genius of, say, Einstein or Beethoven was biochemical information flows. “Are organisms really just algorithms and is life really just data processing” (p. 402)? [The end of the book, and now he questions these concepts?]

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