Homo Deus: A Brief History of Tomorrow

by Yuval Noah Harari

There are no longer natural famines in the world; there are only political famines. If people in Syria, Sudan or Somalia starve to death, it is because some politician wants them to.

malicious demons and angry gods, and did not suspect the existence of bacteria and viruses. People readily believed in angels and fairies, but they could not imagine that a tiny flea or a single drop of water might contain an entire armada of deadly predators.

We don’t need to wait for the Second Coming in order to overcome death. A couple of geeks in a lab can do it. If traditionally death was the speciality of priests and theologians, now the engineers are taking over.

Although average life expectancy has doubled over the last hundred years, it is unwarranted to extrapolate and conclude that we can double it again to 150 in the coming century. In 1900 global life expectancy was no higher than forty because many people died young from malnutrition, infectious diseases and violence. Yet those who escaped famine, plague and war could live well into their seventies and eighties, which is the natural life span of Homo sapiens.

truth, so far modern medicine hasn’t extended our natural life span by a single year. Its great achievement has been to save us from premature death, and allow us to enjoy the full measure of our years.

Our ideological commitment to human life will never allow us simply to accept human death. As long as people die of something, we will strive to overcome it.

People want to live for ever, so they compose an ‘immortal’ symphony, they strive for ‘eternal glory’ in some war, or even sacrifice their lives so that their souls will ‘enjoy everlasting bliss in paradise’. A large part of our artistic creativity, our political commitment and our religious piety is fuelled by the fear of death.

Healing is the initial justification for every upgrade.

Humanism has dominated the world for 300 years, which is not such a long time. The pharaohs ruled Egypt for 3,000 years, and the popes dominated Europe for a millennium. If you told an Egyptian in the time of Ramses II that one day the pharaohs will be gone, he would probably have been aghast. ‘How can we live without a pharaoh? Who will ensure order, peace and justice?’ If you told people in the Middle Ages that within a few centuries God will be dead, they would have been horrified. ‘How can we live without God? Who will give life meaning and protect us from chaos?’ Looking back, many think that the downfall of the pharaohs and the death of God were both positive developments. Maybe the collapse of humanism will also be beneficial. People are usually afraid of change because they fear the unknown. But the single greatest constant of history is that everything changes.

Within a century, our impact may surpass that of the asteroid that killed off the dinosaurs 65 million years ago.

During the Scientific Revolution humankind silenced the gods too. The world was now a one-man show. Humankind stood alone on an empty stage, talking to itself, negotiating with no one and acquiring enormous powers without any obligations. Having deciphered the mute laws of physics, chemistry and biology, humankind now does with them as it pleases.

When biotechnology, nanotechnology and the other fruits of science ripen, Homo sapiens will attain divine powers and come full circle back to the biblical Tree of Knowledge. Archaic hunter-gatherers were just another species of animal. Farmers saw themselves as the apex of creation. Scientists will upgrade us into gods.

Indeed, 99 per cent of bodily activities, including muscle movement and hormonal secretions, take place without any need of conscious feelings. So why do the neurons, muscles and glands need such feelings in the remaining 1 per cent of cases?

You cannot settle the Greek debt crisis by inviting Greek politicians and German bankers to either a fist fight or an orgy.

As long as all Sapiens living in a particular locality believe in the same stories, they all follow the same rules, making it easy to predict the behaviour of strangers and to organise mass-cooperation networks. Sapiens often use visual marks such as a turban, a beard or a business suit to signal ‘you can trust me, I believe in the same story as you’.

Stories serve as the foundations and pillars of human societies. As history unfolded, stories about gods, nations and corporations grew so powerful that they began to dominate objective reality. Believing in the great god Sobek, the Mandate of Heaven or the Bible enabled people to build Lake Fayum, the Great Wall of China and Chartres Cathedral. Unfortunately, blind faith in these stories meant that human efforts frequently focused on increasing the glory of fictional entities such as gods and nations, instead of bettering the lives of real sentient beings.

Religion is any all-encompassing story that confers superhuman legitimacy on human laws, norms and values. It legitimises human social structures by arguing that they reflect superhuman laws.

To cut a long story short, most peer-reviewed scientific studies agree that the Bible is a collection of numerous different texts composed by different human authors centuries after the events they purport to describe, and that these texts were not assembled into a single holy book until long after biblical times. For example, whereas King David probably lived around 1000 BC, it is commonly accepted that the book of Deuteronomy was composed in the court of King Josiah of Judah, sometime around 620 BC, as part of a propaganda campaign aimed at strengthening Josiah’s authority. Leviticus was compiled at an even later date, no earlier than 500 BC.

Hence according to our best scientific knowledge, the Leviticus injunctions against homosexuality reflect nothing grander than the biases of a few priests and scholars in ancient Jerusalem. Though science cannot decide whether people ought to obey God’s commands, it has many relevant things to say about the provenance of the Bible. If Ugandan politicians think that the power that created the cosmos, the galaxies and the black holes becomes terribly upset whenever two Homo sapiens males have a bit of fun together, then science can help disabuse them of this rather bizarre notion.

Islamic fundamentalists want to reach heaven in order to be happy, liberals believe that increasing human liberty maximises happiness, and German nationalists think that everyone would be better off if Berlin is allowed to run the planet. According to Harris, Islamists, liberals and nationalists have no ethical dispute; they have a factual disagreement about how best to realise their common goal.