History professor Yuval Noah Harari — author of Sapiens: A Brief History of Mankind — explains why humans have dominated Earth. The reason is not what you might expect.

70,000 years ago humans were insignificant animals. The most important thing to know about prehistoric humans is that they were unimportant. Their impact on the world was very small, less than that of jellyfish, woodpeckers or bumblebees.

Today, however, humans control this planet. How did we reach from there to here? What was our secret of success, that turned us from insignificant apes minding their own business in a corner of Africa, into the rulers of the world?

We often look for the difference between us and other animals on the individual level. We want to believe that there is something special about the human body or human brain that makes each individual human vastly superior to a dog, or a pig, or a chimpanzee. But the fact is that one-on-one, humans are embarrassingly similar to chimpanzees. If you place me and a chimpanzee together on a lone island, to see who survives better, I would definitely place my bets on the chimp.

The real difference between us and other animals is on the collective level. Humans control the world because we are the only animal that can cooperate flexibly in large numbers. Ants and bees can also work together in large numbers, but they do so in a very rigid way. If a beehive is facing a new threat or a new opportunity, the bees cannot reinvent their social system overnight in order to cope better. They cannot, for example, execute the queen and establish a republic. Wolves and chimpanzees cooperate far more flexibly than ants, but they can do so only with small numbers of intimately known individuals. Among wolves and chimps, cooperation is based on personal acquaintance. If I am a chimp and I want to cooperate with you, I must know you personally: What kind of chimp are you? Are you a nice chimp? Are you an evil chimp? How can I cooperate with you if I don’t know you?

Only Homo sapiens can cooperate in extremely flexible ways with countless numbers of strangers. One-on-one or ten-on-ten, chimpanzees may be better than us. But pit 1,000 Sapiens against 1,000 chimps, and the Sapiens will win easily, for the simple reason that 1,000 chimps can never cooperate effectively. Put 100,000 chimps in Wall Street or Yankee Stadium, and you’ll get chaos. Put 100,000 humans there, and you’ll get trade networks and sports contests.

Cooperation is not always nice, of course. All the terrible things humans have been doing throughout history are also the product of mass cooperation. Prisons, slaughterhouses and concentration camps are also systems of mass cooperation. Chimpanzees don’t have prisons, slaughterhouses or concentration camps.

Yet how come humans alone of all the animals are capable of cooperating flexibly in large numbers, be it in order to play, to trade or to slaughter? The answer is our imagination. We can cooperate with numerous strangers because we can invent fictional stories, spread them around, and convince millions of strangers to believe in them. As long as everybody believes in the same fictions, we all obey the same laws, and can thereby cooperate effectively.

This is something only humans can do. You can never convince a chimpanzee to give you a banana by promising that after he dies, he will go to Chimpanzee Heaven and there receive countless bananas for his good deeds. No chimp will ever believe such a story. Only humans believe such stories. This is why we rule the world, whereas chimps are locked up in zoos and research laboratories.

It is relatively easy to accept that religious networks of cooperation are based on fictional stories. People build a cathedral together or go on crusade together because they believe the same stories about God and Heaven. But the same is true of all other types of large-scale human cooperation. Take for example our legal systems. Today, most legal systems are based on a belief in human rights. But human rights are a fiction, just like God and Heaven. In reality, humans have no rights, just as chimps or wolves have no rights. Cut open a human, and you won’t find there any rights. The only place where human rights exist is in the stories we invent and tell one another. Human rights may be a very attractive story, but it is only a story.

The same mechanism is at work in politics. Like gods and human rights, nations are fictions. A mountain is something real. You can see it, touch it, smell it. But the United States or Israel are not a physical reality. You cannot see them, touch them or smell them. They are just stories that humans invented and then became extremely attached to.

It is the same with economic networks of cooperation. Take a dollar bill, for example. It has no value in itself. You cannot eat it, drink it or wear it. But now come along some master storytellers like the Chair of the Federal Reserve and the President of the United States, and convince us to believe that this green piece of paper is worth five bananas. As long as millions of people believe this story, that green piece of paper really is worth five bananas. I can now go to the supermarket, hand a worthless piece of paper to a complete stranger whom I have never met before, and get real bananas in return. Try doing that with a chimpanzee.

Indeed, money is probably the most successful fiction ever invented by humans. Not all people believe in God, or in human rights, or in the United States of America. But everybody believes in money, and everybody believes in the dollar bill. Even Osama bin Laden. He hated American religion, American politics and American culture — but he was quite fond of American dollars. He had no objection to that story.

To conclude, whereas all other animals live in an objective world of rivers, trees and lions, we humans live in dual world. Yes, there are rivers, trees and lions in our world. But on top of that objective reality, we have constructed a second layer of make-believe reality, comprising fictional entities such as the European Union, God, the dollar and human rights.

And as time passes, these fictional entities have become ever more powerful, so that today they are the most powerful forces in the world. The very survival of trees, rivers and animals now depends on the wishes and decisions of fictional entities such as the United States and the World Bank — entities that exist only in our own imagination.

Featured image courtesy iStock.