There is a new and frantic urgency in Harari’s writing, a tone that is quite different from the agreeable, leisured, scholarly tone of Sapiens, or from the cool speculative evaluation of humankind’s long-term future in Homo Deus, the book that followed it. We are running out of time, he says, to deal with the biggest challenge our species has ever confronted ... Harari’s book ranges across a huge territory: the nature of justice, the seductive appeal of identity politics, the failures of liberal democracies. It is erudite, illuminating, vivid. His lessons suggest new ways of thinking about current problems; they are less about answers than pleading with us to recognise and respond to the immediate threats they pose ... a splendid, sobering, stirring call to arms.

In his fascinating new book, 21 Lessons for the 21st Century, the historian Yuval Noah Harari creates a useful framework for confronting these fears ... 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 ... 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 ... This is easy to mock, but as someone who’s taking a course on mindfulness and meditation, I found it compelling ... As much as I admire Harari and enjoyed 21 Lessons, I didn’t agree with everything in the book ... I wanted to see more nuance in Harari’s discussion of data and privacy ... I was also dissatisfied with the chapter on community ... he undersells the benefits of connecting family and friends around the world. He also creates a straw man by asking whether Facebook alone can solve the problem of polarization. On its own, of course it can’t ... But Harari is such a stimulating writer that even when I disagreed, I wanted to keep reading and thinking.

The [book's] result is a mixed bag. A profusion of platitudes, well-known vignettes, stock phrases and clichés coexists with the brilliant observations that distinguish Harari’s writings ... Alongside some of the bromides he relies on to dispatch major problems, Harari also offers an abundance of fascinating interpretations and comments ... 21 Lessons for the 21st Century is a defective book and probably the weakest of Harari’s oeuvre. Yet, it is a testament to his brilliance that this book has much to engage the curious mind.

21 Lessons for the 21st Century is, as the title suggests, a loose collection of themed essays, many of which build on articles for the New York Times, Bloomberg and elsewhere. That has strange results ... The best reason not to throw this book out of the window is that, occasionally, Harari writes a paragraph that is genuinely mind-expanding ... There are plenty of provocations – why climate change might benefit the Russian economy, how humans could evolve into different species – but the globetrotting, history-straddling scope of Harari’s approach has an obvious drawback, which is that some of the observations here feel recycled. His sweeping statements, breathtaking though they are, can also feel untethered from the intellectual traditions from which they come ... Ultimately, the smudges and slips of Sapiens are forgivable, because it’s a rollicking good read and I suspect it acts as a gateway drug to more academic accounts of human history. However, this book sees Harari enter that class of gurus who are assumed to be experts on everything. The 22nd lesson of this book is obvious: no single member of the tribe Homo Sapiens can know everything. If this new age needs new stories, then we have to let more people tell them.

We should, he recommends, 'switch from panic mode to bewilderment.' Try telling yourself, he encourages the reader, 'I just don’t understand what’s going on in the world.' The author, by contrast, writes as if he understands absolutely everything about what’s going on in the world but needn’t stoop to details. Many of the book’s chapters have their genesis in occasional pieces of journalism, and much of the text is windy punditry. There are many generalizing statements next to which this skeptical reader penciled, in the jargon of Wikipedia, 'citation needed' ... Mr. Harari’s idea of technology is similarly more concerned with broad sweep than fact and plausibility ... This book is marketed as history and promises to guide us through the present and near future, and yet by the conclusion its overriding tone is rather mystically navel-gazing.

If there were such a thing as a required instruction manual for politicians and thought leaders, Israeli historian Yuval Noah Harari’s 21 Lessons for the 21st Century would deserve serious consideration ... For all the breadth of his concerns, Harari is able to distill the most pressing challenges facing our world down to three: nuclear war, ecological collapse and technological disruption ... His concise essays on terrorism and immigration are examples of the fresh thinking he brings to any subject ... thoughtful readers will find 21 Lessons for the 21st Century to be a mind-expanding experience.

... Harari is whimsical, imaginative, edgy, much given to leaping, dizzying sentences ... Harari frequently admonishes readers that the political problem of the future will probably not be oppression or exploitation but rather irrelevance... It is one more example—along with his failure ever to recommend, or even describe, people acting together for political purposes—of how 21 Lessons for the 21st Century, for all Harari’s brilliance, remains within the moral limits of a TED talk: never describe the crimes of, or urge action against, the corporate, financial, and governmental powers-that-be, who are, after all, such very good friends of the good people who run the TED talks.

I might get lucky and die before Yuval Noah Harari’s dark predictions come true. That’s what I found myself thinking while reading Mr. Harari’s 21 Lessons for the 21st Century. The Jerusalem-based historian’s third book begins with a bracing look at trends in artificial intelligence and biotechnology that — unchecked by Earth’s reeling democracies and surging autocracies — could change the nature of humanity as early as 2050 ... If you’re reasonably comfortable with a world in which people have some modicum of control over their lives, Mr. Harari’s book will scare you ... But I don’t regret taking Mr. Harari’s 21 Lessons. We need to know what we’re up against.

Harari proves that he has not lost his touch, casting a brilliantly insightful eye on today’s myriad crises, from Trump to terrorism, Brexit to big data ... Most readers will find Harari’s narrative deliciously reasonable, including his explanation of the stories (not actually true but rational) of those who elect dictators, populists, and nationalists. His remedies for wildly disruptive technology (biotech, infotech) and its consequences (climate change, mass unemployment) ring true, provided nations act with more good sense than they have shown throughout history. Harari delivers yet another tour de force.

Magnificently comb[es] historical, scientific, political, and philosophical perspectives ... Within this broad construct, Harari discusses many pressing issues, including problems associated with liberal democracy, nationalism, immigration, and religion. This well-informed and searching book is one to be savored and widely discussed.