21 LESSONS FOR THE 21ST CENTURY
By Yuval Noah Harari
372 pp. Spiegel & Grau. $28.

The human mind wants to worry. This is not necessarily a bad thing — after all, if a bear is stalking you, worrying about it may well save your life. Although most of us don’t need to lose too much sleep over bears these days, modern life does present plenty of other reasons for concern: terrorism, climate change, the rise of A.I., encroachments on our privacy, even the apparent decline of international cooperation.

In his fascinating new book, “21 Lessons for the 21st Century,” the historian Yuval Noah Harari creates a useful framework for confronting these fears. While his previous best sellers, “Sapiens” and “Homo Deus,” covered the past and future respectively, his new book is all about the present. The trick for putting an end to our anxieties, he suggests, is not to stop worrying. It’s to know which things to worry about, and how much to worry about them. As he writes in his introduction: “What are today’s greatest challenges and most important changes? What should we pay attention to? What should we teach our kids?”

These are admittedly big questions, and this is a sweeping book. There are chapters on work, war, nationalism, religion, immigration, education and 15 other weighty matters. But its title is a misnomer. Although you will find a few concrete lessons scattered throughout, Harari mostly resists handy prescriptions. He’s more interested in defining the terms of the discussion and giving you historical and philosophical perspective.

He deploys, for example, a clever thought experiment to underscore how far humans have come in creating a global civilization. Imagine, he says, trying to organize an Olympic Games in 1016. It’s clearly impossible. Asians, Africans and Europeans don’t know that the Americas exist. The Chinese Song Empire doesn’t think any other political entity in the world is even close to being its equal. No one even has a flag to fly or anthem to play at the awards ceremony.

The point is that today’s competition among nations — whether on an athletic field or the trading floor — “actually represents an astonishing global agreement.” And that global agreement makes it easier to cooperate as well as compete. Keep this in mind the next time you start to doubt whether we can solve a global problem like climate change. Our global cooperation may have taken a couple of steps back in the past two years, but before that we took a thousand steps forward.

So why does it seem as if the world is in decline? Largely because we are much less willing to tolerate misfortune and misery. Even though the amount of violence in the world has greatly decreased, we focus on the number of people who die each year in wars because our outrage at injustice has grown. As it should.

Here’s another worry that Harari deals with: In an increasingly complex world, how can any of us have enough information to make educated decisions? It’s tempting to turn to experts, but how do you know they’re not just following the herd? “The problem of groupthink and individual ignorance besets not just ordinary voters and customers,” he writes, “but also presidents and C.E.O.s.” That rang true to me from my experience at both Microsoft and the Gates Foundation. I have to be careful not to fool myself into thinking things are better — or worse — than they actually are.

What does Harari think we should do about all this? Sprinkled throughout is some practical advice, including a three-prong strategy for fighting terrorism and a few tips for dealing with fake news. But his big idea boils down to this: Meditate. Of course he isn’t suggesting that the world’s problems will vanish if enough of us start sitting in the lotus position and chanting om. But he does insist that life in the 21st century demands mindfulness — getting to know ourselves better and seeing how we contribute to suffering in our own lives. This is easy to mock, but as someone who’s taking a course on mindfulness and meditation, I found it compelling.