It is a long book, almost 500 pages, but it covers the entirety of human prehistory and history, up until the present day, which for the author was 2014. You will not find lists of empires and dates. In this way, it is almost the exact opposite of what is still perhaps the most famous overview of world history, the Outline of History by H. G. Wells.
Instead, the author seeks general trends and explanations for everything that has happened. Here is an example. Why did human evolution seem to proceed so slowly before the arrival of modern humans? For example, Homo ergaster stone tools in Africa remained unchanged for a million years. Harari says that all other animal species, and all humans before Homo sapiens, have or had a biological constraint on their ability to think of new ways of living. Before the human lineage could make any progress, we needed an innovation, invisible in bones and DNA, which allowed us to imagine the future. Neanderthals, for example, he said, did not have “the ability to compose fiction.”
But the author suffers from the delusion of technological optimism, which is very common among writers of popular sociology. Here are two examples which considerably erode the credibility of the conclusion of the book.
First, he seems to assume we will never run out of energy. This is because we invest some of the profits from the old kinds of energy into developing new ones. This has, in fact, happened. One obvious example is that England was running out of wood, so they invested money and research into using coal, which required the invention of the steam engine. Before modern times, all energy was either from burning wood or from human and animal muscle power. Medieval people did not even imagine steam, hydroelectric, or atomic power.
But this will happen only if we deliberately invest in new technology. Right now we need to invest in green technologies such as wind and solar energy. We have done so, but powerful ideological and political forces oppose the adoption of green technology. Donald Trump has made it very clear that his solution to our future energy needs is to pump more oil. Technology will not save us, because Trump will lead us boldly into the twentieth century.
Harari also speculated that wars were becoming rare. It is true that there were fewer wars in 2014 than there had ever been in the past. This was easy to believe in the balmy days of the Obama administration. But almost as soon as Harari’s book was published, Putin decided to invade the Ukraine, for reasons that are not clear even to his supporters, who do not dare to have an independent opinion; and Harari’s own country, Israel, is waging what many observers claim to be a war of extermination against the Palestinians.
Harari even speculated about how to be happy. Happiness is, he said, the product of serotonin levels in the brain. No matter what your external circumstances happen to be, no matter if you are in pain or slavery, you will be happy if you have a lot of serotonin. I think this opinion is a product of the author’s scarcely-hidden admiration for Buddhism. And, he implies, serotonin levels are not only biologically determined—you are either a happy or a depressed person—but also remain unchanged during your life. But this is true only for people who are clinically depressed. They need more serotonin but I do not. Also, I am certain that I am happier now, having completed so many of my life goals, than I was back when I had no idea if my future would be successful.
We need to admit that lots of things are getting better—the same message as Steven Pinker’s Better Angels of Our Nature—but that we still have a lot of work to do and our success is not assured.
We all live in imagined realities. Despite the absence of evidence for spiritual realities, we will be individually unhappy and collective failures if we live in the way the apostle Paul described in one of his epistles: Eat, drink, for tomorrow we die. We have to at least imagine that we can make the world better.
