10 August 2018

The title, The Secret of Our Success, may lead this book be mistaken for a self-help manual, to be shelved alongside 12 Rules for Life and The Seven Habits of Highly Successful People. But this is a far more serious book with a far larger canvas. And a much better book. Joe Henrich, an anthropologist by training, is professor of human evolutionary biology at Harvard. His purpose is to ask why humans are the ecologically dominant species on earth. So The Secret of Our Success is not a book about economics. In fact the only references to economics in the index are two – to economic games, such as the ultimatum game, and to economic norms, as resolution of such games. But this is a book which invites us to change the way we think about economics. Humans are amazing. We can land a man on the moon. We can fly 500 people to Australia in less than 24 hours. We can create nuclear explosions that will destroy a city, or if we prefer, supply that city with electricity for 50 years. We can build computers that fit in our pockets, send messages, calculate the square root of any number, navigate you to your destination, and on which you can read any one of millions of novels. And yet our physical achievements are unimpressive. Many other mammals can knock us down with ease. We cannot, unaided, rise more than 6 foot above the ground. Most cats can outrun us. And our children can survive only after they have been dependent on their parents for years. The obvious answer is that we have big brains and so we are smart. But Henrich claims that we’re not that smart. He devotes an early chapter to the subject of lost European explorers. He describes Franklin’s expedition in 1845 to find the north-west passage, which ended with the death of the captain and his crew of 100. The ship had food and other provisions to last for years, a well-stocked library, fuel, insulation and desalinators, but the ship became locked in ice, and the crew was unable to survive in the Arctic conditions. And yet these are conditions in which other humans, native tribes have been able to live for thousands of years. But Franklin’s crew was unable to work out how to do so. Burke and Wills were the first Europeans to cross Australia, but died on the return journey. King, the third member of their expedition, lived but only because he successfully made contact with an aboriginal tribe which looked after him until a rescue party arrived. And that is the key point. Franklin, Burke and Wills were intelligent and resourceful. But they could not survive in unfamiliar circumstances without the collective intelligence which other groups of humans had developed but they lacked. Cultural evolution over long periods of time has established knowledge which enable indigenous people to manage life in the cold of northern Canada and the dry interior of Australia. And without access to this knowledge, Franklin, Burke and Wills died. Humans can send rockets to the moon, exploit nuclear fission, and build smartphones. But no individual knows how to do any of these things. Thousands of people, working together, do. As the primate specialist Mike Thomasello has observed, you never see two chimpanzees carrying a log together. Adam Smith began the Wealth of Nations with a description of the pin factory, in which specialisation by task created a business unit far more productive than any individual pin-maker could achieve. But the ‘progress of opulence’ Smith described was only getting started. Contemporary manufacturing capabilities extend well beyond pins. Today we can build an Airbus 380, a flying machine almost as long as a football pitch, with engines built in one country, wings in another, and put together an extraordinary logistics operation which brings all the parts together for final assembly in Toulouse. Another logistics operation allows the plane to be used for daily flights to Sydney. The ability to engage in large-scale cooperative activity is what makes humans as a species unique. It is the secret of our success as a species. It is certainly the secret of the productivity of modern developed economies. This capability is a challenge to economists whose focus is on the rational optimising individual. A challenge reinforced by Henrich’s observation that other species are better at rational optimisation than us. Pigeons quickly learn to solve the Monty Hall problem, which continues to bemuse most humans. And they can fly, which we can’t, but we don’t need to because we can build Airbuses, which they can’t. Chimpanzees know how to play the ultimatum game as ‘rational’ agents; they make derisory offers which are never refused. But we know how to carry pieces of timber together. And humans have managed to solve much more complicated cooperative tasks, tasks specific to historical and geographical contexts. The folk in Toulouse who assemble Airbuses could not survive in the outback of Australia, and the people who do survive there have no idea how to assemble an Airbus. Henrich describes an exercise in which both toddlers and young chimpanzees were subject to a battery of cognitive tests. On problems like counting, spatial awareness and understanding of causality – if this then that – there is little difference between the performance of very young children and very young monkeys. But there is a dramatic contrast in the capacity for social learning – the ability to learn from the actions and movements of other people as distinct from our own observation of the environment around us. And that capacity for social learning, he argues, is why there is really no difference between the measured intelligence of adult and young chimpanzees, but a large difference when the same comparisons is made for (most) humans. Henrich emphasises three different kinds of learning: individual learning, the process by which infants pick up cues from the world around them; social learning, in which they pick up