Charles Darwin: The single most powerful idea in the sciences and humanities?

Until Darwin it was hard to see how the natural world could have been anything other than designed

Darwin’s importance simply cannot be overstated (Getty)

There are a number of candidates for the single most powerful idea in the history of the sciences and humanities. Nicolaus Copernicus’s heliocentric view of the Earth’s place in the universe is certainly one, as is Einstein’s theory of relativity. However, for the breadth of its application, and the impact that it had on modern civilisation, it would be hard to beat Charles Darwin’s (1809–1882) theory of evolution by natural selection.

Until Darwin’s On the Origin of the Species was published in 1859, it was hard to see how the natural world could have been anything other than designed. The significant point here is its complexity. As William Paley famously argued, it seems almost unimaginable that something as complex and highly wrought as the human eye could possibly have emerged purely by natural mechanisms. The eye just appears too precisely specified to be anything other than the creation of an intelligent entity (by which just about everybody means God). Darwin’s importance is that he showed exactly how this kind of “design” could have occurred without a designer.

Darwin was influenced by Thomas Malthus’s famous essay on population, in which Malthus argued that the capacity of a population to sustain itself tends not to keep up with its rate of growth. The lesson that Darwin took from this is that the living world is necessarily thoroughly competitive (“red in tooth and claw”, as one of his disciples later put it). Life is characterised by a struggle for existence – or, more exactly, for reproduction – since any species will tend to produce more individuals than can be sustained. It was this insight that led Darwin to his theory of evolution by natural selection.