Did early scientists owe a debt to the slave trade?

Naturalists in need of samples took advantage of the routes taken by slave ships

Science is a value-free and progressive enterprise, perhaps the most valuable product of the Enlightenment. But science is performed by scientists, ordinary fallible mortals who do not always walk the bright side of the road – consider eugenics and Nazi-science as two historical examples and, currently, the widespread publication of unreliable data. Most recently, Sam Kean published a paper in Science, Volume 364, Issue 6455, pp 16-20, (April 2019), entitled Historians Expose Early Scientists' Debt to the Slave Trade.

The slave trade was a very dark chapter in human history. It operated from the 15th to the 19th centuries and the principal European countries involved were Britain, Spain, Portugal, France and Holland. Between 1532 and 1832 around 12 million Africans were taken to the Americas as slaves, at least a third of them in British ships. Conditions on slave ships were very harsh and up to two million unfortunate slaves died on the journey.

The slave trade was a three legged journey for British ships – the "triangular trade". Goods such as guns and alcohol were taken to West Africa and traded for slaves. The slaves were then taken across the Atlantic for sale in the West Indies and the Americas. Finally, cargoes such as sugar and rum were taken back to England.

European science boomed in the 1700s. Isaac Newton (1642-1727) published his renowned theory of gravity and telescopes pointed skywards to probe the universe. Robert Hooke (1635-1703) and Anton van Leeuwenhoek (1632-1723) used improved new microscopes to examine the fine structure of biological organisms.


Biology was then in its descriptive phase of examining and classifying the prodigious variety of life on earth. But collecting specimens from countries overseas was a problem. Governments only occasionally sponsored seagoing scientific expeditions. On the other hand, slave trade ships constantly sailed the triangular route Europe-Africa-Americas-Europe.


So, naturalists took advantage of this and enlisted ships’ captains and surgeons to collect samples in Africa and the Americas and return them to Europe. This greatly assisted the assembly of large collections of plants and animals gathered from far and wide. These collections, eventually housed in institutions like The British Museum and The Museum of Natural History, where they remain to this day, were made available for detailed study by naturalists.

The biological sciences were not alone in benefiting from the slave trade. Geologists used the slave ships to bring back rocks and fossils. Astronomers gathered observations on the heavens from slave ports and even Isaac Newton, when working out his theory of gravity, collected tide readings from all over the world. One important set of data came from the French slave trade ports in Martinique.

So, what to make of all this? The slave trade was legal (not outlawed in Britain until 1807) and economically very lucrative and would have operated whether or not naturalists recruited ships’ captains and surgeons to collect samples. Naturalists who used the slave ships to return samples from abroad were not endorsing slavery, just using the only means available to get their hands on scientifically valuable samples.

But, regardless of context, slavery is so grievously immoral I believe these naturalists were wrong to use the slave ships to collect their samples. And I am not aware that any naturalists intervened to try to ameliorate shipboard conditions for the unfortunate African slaves.

However we must be careful about using today’s standards to judge historical events. Humans evolved from ape-like ancestors and human society did not begin with a developed set of moral and ethical standards. Such codes and practices had to be gradually developed over a very long time and, throughout most human history, society was arranged in ways completely unacceptable by today’s standards, for example in vast social inequality and grinding poverty, no democracy or social mobility, savage penal-code penalties, etc.

It is not my intention to endorse bad things that happened in the past but rather to acknowledge the yearning for progress and for doing good that exists in the human spirit. From where human society began progress was the most that could be hoped for – and we have made much progress.

William Reville is an emeritus professor of biochemistry at UCC