Kongo came into intense contact with the Portuguese after it was first visited by the mariner Diogo Cão in 1483. At the time, Kongo was a highly centralized polity by African standards, whose capital, Mbanza, had a population of sixty thousand, which made it about the same size as the Portuguese capital of Lisbon and larger than London, which had a population of about fifty thousand in 1500. The king of Kongo, Nzinga a Nkuwu, converted to Catholicism and changed his name to João I. Later Mbanza’s name was changed to São Salvador. Thanks to the Portuguese, the Kongolese learned about the wheel and the plow, and the Portuguese even encouraged their adoption with agricultural missions in 1491 and 1512. But all these initiatives failed.

Still, the Kongolese were far from averse to modern technologies in general. They were very quick to adopt one venerable Western innovation: the gun. They used this new and powerful tool to respond to market incentives: to capture and export slaves. There is no sign here that African values or culture prevented the adoption of new technologies and practices. As their contacts with Europeans deepened, the Kongolese adopted other Western practices: literacy, dress styles, and house designs.

In the nineteenth century, many African societies also took advantage of the rising economic opportunities created by the Industrial Revolution by changing their production patterns. In West Africa there was rapid economic development based on the export of palm oil and ground nuts; throughout southern Africa, Africans developed exports to the rapidly expanding industrial and mining areas of the Rand in South Africa. Yet these promising economic experiments were obliterated not by African culture or the inability of ordinary Africans to act in their own self-interest, but first by European colonialism and then by postindependence African governments.

The real reason that the Kongolese did not adopt superior technology was because they lacked any incentives to do so. They faced a high risk of all their output being expropriated and taxed by the all-powerful king, whether or not he had converted to Catholicism. In fact, it wasn’t only their property that was insecure. Their continued existence was held by a thread. Many of them were captured and sold as slaves—hardly the environment to encourage investment to increase long-term productivity. Neither did the king have incentives to adopt the plow on a large scale or to make increasing agricultural productivity his main priority; exporting slaves was so much more profitable.

It might be true today that Africans trust each other less than people in other parts of the world. But this is an outcome of a long history of institutions which have undermined human and property rights in Africa. The potential to be captured and sold as a slave no doubt influenced the extent to which Africans trusted others historically.