Modern science has been hugely shaped by the work of Darwin and Newton, but just how relevant are they?Susan Q Yin

Charles Darwin and Isaac Newton are without a doubt among the most influential scientists to have studied at Cambridge. As a first-year natural scientist, they are mentioned to me all the time by enthusiastic physics or biology lecturers, or even by proud students from Trinity (Newton) or Christ’s (Darwin). As they worked in two different scientific disciplines, it is difficult to compare the impacts of their work, but I believe that doing so can illustrate the role that the history of science plays in our thinking today. What can we really say about the influence these two have had? And why do we still bother talking about men that have been dead for hundreds of years?

Newton published his Philosophiae Naturalis Principia Mathematica in 1687, during the height of the scientific revolution. His primary contribution to science was his study of motion. His three famous laws allow us to calculate the motion of any object, so long as we know the forces acting upon it. He was also the first to formulate a mathematical law of gravity, which enabled him to accurately predict the motion of the earth, the moon, and the other bodies in the solar system, confirming earlier observations and ideas by Galileo and Kepler. As part of this work, he developed new mathematical tools such as derivation and integration, which ultimately resulted in the mathematical field of calculus.

Newton was also the first to formulate the now conventional idea of time. Time, according to Newton, was not a measure of change, as Aristotle had originally thought, but a rigidly ticking clock, fully independent of everything else in the world. With his work, he laid the foundation of physics today.

“Time, according to Newton, was […] a rigidly ticking clock, fully independent of everything else in the world.”

It was almost two centuries later, in 1859, when Charles Darwin’s On the Origin of Species introduced the theory of evolution by natural selection to the world. Darwin explained how the fantastic diversity we see in nature can be explained by a set of very simple rules, summarised as ‘multiply, vary, let the strongest live and the weakest die’ – survival of the fittest. It is virtually impossible to overstate the importance of this work to modern biology. 'Nothing in biology makes sense except in the light of evolution', Theodosius Dobzhansky famously writes, coining the slogan that shapes the views of many biologists today. The theory of natural selection was not Darwin’s only contribution to biology. In an attempt to explain the peacock’s luxurious feathers, he developed the idea of sexual selection: some traits do not arise because they aid survival, but because they make it easier to find mates.

Outside of biology, Darwin’s work may have been just as influential, shaking up conventional ideas about nature and our position within it. The natural world was no longer created by God in perfect harmony but rather a brutal ‘struggle for existence’. With that, the walls that centuries of Christian theology had erected between humans and animals came crumbling down. No longer the image of God, man turned out to be nothing but a hairless ape. Although these ideas were ridiculed at the time and are still not accepted by many, their long-term influence has been enormous, and their colossal importance been likened by Freud to Copernicus’ discovery that the earth is moving around the sun.

“the walls that centuries of Christian theology had erected between humans and animals came crumbling down”

Although I think Darwin’s influence on our thinking about the world today is far greater than that of Newton, one could argue that it is partly because of Newton that Darwin undertook the enormous task of trying to explain ‘the origin of species’ in the first place. When Darwin was at Cambridge in the early 19th century, Newton was celebrated as the ultimate scientist, the example that everyone should try to follow. Newton was at the crux of the idea that science should be about finding general laws that can explain a large number of phenomena, rather than describing or explaining different phenomena separately. That is exactly what Darwin did in his work, bringing a massive body of evidence together in one big ‘law of biology’: the theory of natural selection. In a way, Darwin became the Newton of biology; it may not be a coincidence that he decided to mention ‘the fixed law of gravity’ in the last sentence of The Origin.

Science has come a long way since Newton and Darwin published their famous works. Einstein’s theories of relativity showed that Newton’s laws no longer hold at very high speeds, or near very massive objects. And with the discovery of the principles of genetics and the molecular structure of DNA, the carrier of genetic information, new worlds opened up which Darwin may have never even considered possible. However, these are not falsifications of Newton’s and Darwin’s ideas, nor are they the start of a ‘new paradigm’, as is sometimes suggested. They are extensions of their theories and merely show that the project of science is never finished.


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We have to be careful in the way we speak about the history of science. By focusing solely on the roles of a few brilliant individuals, we deny the fact that science is ultimately a collaborative effort, and that new ideas rarely arise in complete isolation. Many have criticised the idolisation of Newton in physics and mathematics and have pointed out that a number of his contemporaries, Descartes and particularly Leibniz, had been working on very similar concepts at the time. A similar thing (albeit to a lesser extent) can be said for Darwin, as Alfred Russell Wallace came up with very similar ideas about evolution around the same time. There is something to be said for both sides. We should celebrate the work and ideas of some of the brightest minds that ever lived without ignoring the contributions of all the others whose names we have forgotten, and we should keep on working, collectively, on the fantastic project that is science.