Charles Darwin, one of history's most influential scientists, was born on August 12th, 1809. Newton had dispelled the notion that there were two domains, the heavens and the Earth, by showing that the same laws that governed motion on Earth also governed the motions of heavenly bodies. Now Darwin was to achieve a similar result for nature, showing that there were not two domains, humans and the animal kingdom, but that humans were part of the animal kingdom and subject to the processes that governed its development. Both Newton and Darwin therefore edged humanity away from a human-centred view of the universe, and into a position that saw human beings as a part of the universe and a product of it.
His 5-year voyage on HMS Beagle had given him scientific recognition as a geologist, one whose observations and samples supported Charles Lyell's notion of gradual geological change over long periods of time. But it was his observation of the different species scattered across different islands that aroused his interest. He had read "An Essay on the Principle of Population," published by Robert Malthus in 1798, which suggested that human population would always grow at a faster rate than the food supply, causing periodic catastrophes of starvation. If many were doomed to die, Darwin wondered which ones would survive, and the question led him to develop the theory of natural selection. He wrote:
"In October 1838, that is, fifteen months after I had begun my systematic enquiry, I happened to read for amusement Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The result of this would be the formation of new species. Here, then, I had at last got a theory by which to work..."
Darwin published his theory of evolution with a weight of supporting evidence in his 1859 book "On the Origin of Species," and the world was never the same. One of the interesting features of his account was that it included a process of change, a process by which one thing gradually became another. Unlike accounts of change such as Hegel's, for example, that thought change occurred abruptly, Darwin's was one of slow incremental change, evolution rather than revolution.
Radicals such as Marx have supposed that changes to society must come in abrupt leaps achieved by revolution, and have proposed what those changes should be. Some have inspired others to seize power in order to impose those sudden changes. The more evolutionary approach takes it that free societies change gradually over time as people develop new ways of doing things and new ways of looking at things. Values change over time, as do practices and habits. Under this framework, changes come about by gradual adoption. The innovators are the early adopters, but others observe the results, and copy the new behaviour if they seem favourable.
In "The Poverty of Historicism" (1957), Karl Popper contrasts what he calls "Utopian social engineering" with "piecemeal social engineering," describing the former as "a method which, if really tried, may easily lead to an intolerable increase in human suffering." The latter, by contrast, he describes as "a reasonable method of improving the lot of man." The lessons of the French and Russian revolutions bear out the view that sudden, imposed, revolutionary change can easily bring disaster. The Industrial Revolution and the gradual spread of capitalism as a global wealth-creating process have brought about by gradual change the biggest advances in human welfare since hunter-gatherers became farmers.
The process Darwin saw in nature of gradual, incremental change has proved to be one that people can apply to the improvement of society and to the quality of life, as well as to expanding the choices and opportunities that are available to people. Evolution brings improvement, where revolution often brings only disaster.