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In 1860 Thomas Henry Huxley introduced the term Darwinism in relation to Charles Darwin’s book On the Origin of Species, published the year before. Darwin’s book presented natural selection as the means of biological evolution, as seen in the full title, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. Darwinism, then, is correctly understood as the body of theory dealing with biological evolution in general and evolution by natural selection in particular.
In 1864 the philosopher Herbert Spencer summed up Darwinism with the phrase “survival of the fittest.” Darwin approved of this summation as an accurate and convenient expression of his basic theory. The concept of survival of the fittest was challenged by Henry Drummond of the Scottish Free Church, who pointed out that even in the animal world survival is not simply a matter of stealth and strength. Care and compassion also play an important role.
Charles Darwin published a second book on evolution in 1871, The Descent of Man and Selection in Relation to Sex. In it he theorized that nature itself determined the development and progress of all living things. The implication was that any man-centered or God-centered view of the world is merely wishful thinking.
Darwinism has been applied to areas other than biology. “Social Darwinism,” for example, is the application of the Darwinian principle of struggle to the struggle for dominance within society; from this emerged the “science” of eugenics. By the end of the 1950s, the term Darwinism had been updated to incorporate natural selection with population genetics and Mendelian genetics. Historians often use the term Darwinism to differentiate Darwin’s theory from other evolutionary theories that existed around the same time.
The modern scientific community uses the term Darwinism to distinguish Darwin’s original theories from modern evolutionary theories (sometimes called “neo-Darwinism”). Scientists today do not rely solely on Darwin’s original ideas with regard to modern biology.
Some creationists misuse the term Darwinism by applying it to atheistic evolution in general. Technically, Darwinism has no connection with cosmic evolution, the Big Bang theory, or the origin of life, per se. Biological Darwinism does not deal with how life started, only with how life progressed and diversified.