Sapiens: A Brief History of Humankind

Sapiens: A Brief History of Humankind by Yuval Noah Harari

A remarkable book by a very smart guy. I found the book enlightening, and provocative, and enjoyed reading it.

Harari begins with physics (“About 13.5 billion years ago, matter, energy, time and space came into being…”) and ends with theology (“Is there anything more dangerous than dissatisfied and irresponsible gods who don’t know what they want?”). In between, he uses three “revolutions”: cognitive, agricultural, and scientific to divide our human story.

The cognitive revolution, occurring about 70,000 years ago, marks the time when Homo Sapiens developed the ability to think abstractly. Although earlier humans, and many animals and birds, could communicate present-time, material observations, “Danger! There!”, humans could now communicate imaginatively about past and future possibilities: “I saw a lion at the river yesterday. Maybe we could kill it or scare it off.” This advance did not result from a larger physical brain but from an increase in the neuronal connections within the brain, probably due to a fortunate mutation. With their new ability, Homo Sapiens moved from the lower-middle of the food chain to become the planet’s dominant predator. And Homo Sapiens quickly became the dominant human species as well. The Neanderthals died out about 30,000 BCE. Our last remaining cousins, Homo Floresiensis, isolated on an island in Indonesia, went extinct about 13,000 BCE.

The agricultural revolution, occurring around 12,000 BCE, changed human existence from nomadic hunter-gatherers, to settled farmers and pastoralists. Although raising your own food sounds like a strategic hedge against the arbitrariness of nature, Harari points out that agriculture set a seductive trap with negative effects. Diet variety was greatly reduced as humans depended increasingly on a few food crops. Disease increased due to living in proximity to animals. Farm work required more hours each day. Property required defending. Crops needed protection from pests and vermin. Specialized professions developed: soldiers, accountants, lawyers, priests to pray for rain, and rulers to oversee it all. Writing developed around 5,000 BCE first as a means of accounting, for taxes, and then for more complicated records like leases and property titles. Epic poems could be memorized, but legal documents required writing and record-keeping.

Between the agricultural revolution and the scientific, Harari traces the human story as one of expansion and unification. The ability of humans to think abstractly allowed humans to create large communities gathered around imaginary ideas like nations, citizenship, or religion. The age of political empires, gave way to empires of religion, or language, or ideologies like democracy, or human rights.

The scientific revolution, of 1500, Harari describes, ironically, as a revolution of ignorance. Prior to this revolution, we were certain that we knew everything that we needed to know. Everything is written in the sacred book. Now, humans began to be excited by the idea that we don’t know everything.

That the scientific revolution of 1500 occurred in Europe, but not in Asia, the Middle East, Africa, or the Americas led to Europe developing as the world power of the modern age. The curiosity about what we don’t know led to the age of exploration followed by conquest and expansion of European empires. Scientific discoveries led to inventions which led to profits which can be re-invested in new experiments leading to further discoveries. That we don’t know everything allowed humans to imagine that the future might be something new, not be merely a continuation of the past. Capitalism funds scientific innovation by using future income, in the form of credit to pay for present-day work. New science creates new technologies which return a profit to investors and the cycle turns again.

Throughout the book Harari dispassionately lays out both the up and down sides of our human history, the times where change seems like progress, and the times where advancing feels more like retreating. Animal extinction, the suffering of domesticated animals in factory farms, the brutality of conquest and empire, slavery, the environmental threat of climate change, are all part of our story as much as is philosophy, art, and the physical sciences unlocking the mysteries of the universe and the atom.

Harari finds great stories to illustrate his points: the Mississippi Bubble for capitalism; measuring the transit of Venus to show the intersection of science and global exploration; Edward the First’s 13 children to show the high level of childhood mortality in pre-modern times; the siege of Numantia to show the irresistible power of empires. I read several of the stories out loud to my husband, a history teacher and we enjoyed them together.

At the end of the book, Harari turns speculative. The second to last chapter puts aside history for a long meditation on the nature of human happiness. Has human evolution and revolution led us to being happier? It’s a fair question, but it doesn’t seem to belong in this book. His final chapter summarizes the work in the last decade or so around genetic modification and developing artificial intelligence. He wrote this book in 2015. I skimmed most of that material. Suddenly trading facts for musings felt jarring to me. Maybe because today seems so unsettled with the coronavirus raging and Trump not quite leaving office yet, I felt myself appreciating when Harari settled old mysteries and resisting when he tried to open new ones. Whether the latest science leads to a new revolution in human history and what the consequences of it might be is a question I can wait to find out.