Homo Deus: A Brief History of Tomorrow

The summary

In 2010 famine and malnutrition killed about a million people. Obesity killed three million. That same year terrorists killed 7,697 people worldwide, which makes Coca-Cola a deadlier threat to the average American than al-Qaeda. In 2012 human violence accounted for 620,000 deaths and diabetes for 1.5 million: sugar is now more dangerous than gunpowder. The claim isn’t that suffering has ended. It’s that famine, plague and war have stopped being forces of nature and become manageable problems — when they break out we convene a commission of inquiry instead of praying. History tolerates no vacuum.

Death becomes a technical problem

The scale of what got solved is easy to forget. Between 1692 and 1694, 2.8 million French people — fifteen per cent of the population — starved while Louis XIV dallied with his mistresses at Versailles. When smallpox landed in Mexico in March 1520 the country held 22 million people; by December, 14 million.

Against that record, modern culture treats death as a glitch. A doctor will tell you that you have flu, tuberculosis or cancer, but never that you have death — every cause is a technical problem awaiting a technical fix. Google founded a subsidiary, Calico, whose stated mission is to solve death, and put 36 per cent of Google Ventures’ $2 billion portfolio into life sciences; the fund’s head says living to 500 is possible. Equality is out; immortality is in.

Harari doesn’t buy the timeline. Modern medicine hasn’t extended the natural human lifespan by a single year — it saved us from dying early. Galileo made it to seventy-seven, Newton to eighty-four, Michelangelo to eighty-eight, without antibiotics. And what money might buy is a-mortality, not immortality: no expiry date, but still killable by a truck.

The glass ceiling on happiness

The second project goes worse. Between 1950 and 2000 American GDP rose from $2 trillion to $12 trillion, yet measured well-being in the 1990s sat roughly where it had been in the 1950s. South Korea went from poor dictatorship to rich democracy and tripled its suicide rate, from nine per 100,000 to thirty.

Two things hold that ceiling down. Expectations balloon as conditions improve, so contentment never catches up. And happiness is biochemical rather than circumstantial: pleasant sensations subside by design. A squirrel that felt permanent bliss after one nut would stop hunting for nuts and leave no descendants. So the pursuit turns pharmaceutical. In 2011, 3.5 million American children took ADHD medication; British prescriptions went from 92,000 in 1997 to 786,000 in 2012. People have quarrelled about schools for millennia, but this is the first era in which changing the pupils’ biochemistry looks like the efficient move.

Modernity’s deal and its escape clause

Underneath sits a bargain Harari reduces to one line: humans give up meaning in exchange for power. No cosmic script means no consolation when things go wrong, but also no ceiling on ambition. The escape clause is humanism, which installed human feeling where God used to sit. A woman in 1300 confessed an affair and was told to give ten gold coins to the crusade and walk to Canterbury. Her descendant tells a therapist, who asks how she feels about it. The voter knows best, the customer is always right, beauty is in the eye of the beholder — three slogans, one creed.

The gun that fires in the third act

Then the sciences humanism relies on start dismantling it. Put someone in a scanner and tell them to press a switch whenever they feel like it, and their brain gives the choice away seconds before they know they’ve made it. Split-brain patients are stranger still: shown a chicken claw on one side and a snow scene on the other, a patient pointed at a chicken with one hand and a snow shovel with the other, then explained that you need a shovel for the chicken shed. The talking hemisphere had no idea, so it invented something plausible.

Kahneman found the same machinery in everyone. Volunteers held a hand in 14°C water for a minute, then did a longer version — that same minute plus thirty seconds as the water warmed by a degree. Eighty per cent chose to repeat the longer, objectively worse trial, because it ended better. There’s an experiencing self that feels everything and remembers nothing, and a narrating self that keeps only peaks and endings and makes all the big decisions. The single authentic inner voice liberalism is built on isn’t there.

When intelligence stops needing consciousness

Computers have gained enormous intelligence since the 1950s and precisely zero consciousness — and for armies and corporations, intelligence is mandatory, consciousness optional. Frey and Osborne put 47 per cent of American jobs at high risk of automation within two decades: 99 per cent for telemarketers, 96 for chefs, 89 for bakers and bus drivers, 0.7 for archaeologists. A robot-run San Francisco pharmacy filled two million prescriptions without error. At a showdown in Oregon, an audience judged a computer’s composition to be genuine Bach and the human composer’s piece to be the machine’s.

The threat isn’t a robot uprising. It’s Waze: a tool you consult becomes a tool you obey, then a tool that decides. Meanwhile medicine shifts from healing the sick, which was egalitarian, to upgrading the healthy, which isn’t — and elites who no longer need millions of healthy workers may stop paying for them.

The bottom line

The successor Harari names is dataism: the universe is data flows, and anything’s value is its contribution to processing them. Humanism told you to listen to your feelings; dataism says listen to the algorithms, because they know how you feel. He insists these are possibilities, not prophecies, and leaves one question: what happens when non-conscious systems know you better than you know yourself. Read it if you want the long view on where biotech and AI are pushing us, and can stomach an author who predicts bluntly, then tells you not to trust him.