Homo Deus is the sequel to Sapiens, Yuval Noah Harari’s bestselling history of humanity. Our species, he argues, has finally tamed war, poverty and plague. Although they still threaten millions of people, they are understood now not as natural phenomenon beyond human control, but as technical problems capable of resolution. Humanity’s next great quest is to overcome death itself. We will try to do so through some combination of genetic manipulation and artificial intelligence. If successful, the result will be the end of Homo Sapiens as the dominant force on earth. We may end up being treated by a new super-species as we treat domesticated animals. Less catastrophic changes will still trigger revolutions in politics, society and economics. The religion of humanism—in which humans have placed themselves at the centre of the universe—will have undone itself. Beware what you wish for.
There is much of interest in Homo Deus, but it is not wholly persuasive. As with Sapiens, the weakest parts concern modern political ideologies. For example, Harari’s critique of liberalism is based on a caricature. Moreover, he exaggerates the ideological and philosophical significance of recent scientific discoveries. He is at his most interesting when surveying possible religions of the future, hatched in the tech laboratories of the world—our gurus will be prophets of “techno-humanism” and “data religion.” Sweeping in its coverage and its claims, at once insightful and exasperating, this is a book to think with and to argue against.