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out, in their practice have taken advantage of these principles to produce constantly better animals, in certain respects. They have picked out the fastest horse to be found to breed for speed and by selecting the fastest of its prodigy they have produced the race horse. In the opposite direction, they have selected the biggest and the strongest to breed for pulling power and have produced the draught horse. So with dogs and pigeons and hens. They have selected the cow that gave the most and the best milk to breed for those qualities and have produced a dozen different varieties of cattle superior in those respects. Now, said Darwin, if there is some force or circumstance or principle that will do with all the creatures of the earth what man does with the domestic animals, then give this principle time enough, and it will account for the different species we find in the world today. Given any one kind of horse to start with, man could produce in the course of time all the varieties which he desires. Now, Nature, said Darwin, has done exactly the same thing with all living creatures. She has "selected,” and by selecting she has produced all the species and varieties that we find in the world.
Nature selects, said Darwin, principally in one way. There are always more young of every species than survive; always more than there would be food for if they should survive. Nature, therefore, sets up a struggle among them all for such food as there is. And if some of the variations, that appear in each new generation, help their possessors in the struggle for food, shelter, or to escape their enemies, then it will be those who vary in these directions that will grow up to reproduce. Those will survive which have the traits that fit them to win out over their competitors. Nature selects all along the line of individuals and species, as man selects among his oxen or his sheep. This process of “Natural Selection," which Darwin first elaborated, Herbert Spencer in more dramatic fashion called "The Survival of the Fittest." The fit survive-naturally. At any rate, the traits of those that do survive will be passed on. Therefore, in differing ages of the world and differing circumstances, as environment changes and the organism invents or stumbles upon new responses to it, new species will be evolved. To put it in Darwin's own words: "As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected. From the strong principle of inheritance, any selected variety will tend to propagate its new and modified
This was what the world had been waiting fora plausible working theory of how the thing had happened. Darwin's book had a popularity that astonished everyone, himself more than anyone else. It went through edition after edition, and was translated even into Japanese and Hindustani. As Huxley said (“Life and Letters of Charles Darwin”): "That which we were looking for and could not find, was an hypothesis respecting the origin of known organic forms which assumed the operation of no causes but such as
Origin of Species, 5th edition, pp. 19-20. Mr. Darwin was careful to state, many times over, that he did not rest his doctrine of evolution upon this one principle, and it is a strange perversion of his teachings to assume that he did. "I am convinced," he said, "that natural selection has been the most important but not the exclusive means of modification,"
could be proved to be actually at work. We wanted not to pin our faith to that or any other speculation, but to get hold of clear and definite conceptions which could be brought face to face with facts and have their validity tested. The ‘Origin' provided us with the working hypothesis we sought.”
Up to the appearance of the "Origin,” Huxley had withheld his assent to any theory of evolution. He now gave it heartily to Darwin's presentation of it. Spencer had been an evolutionist previously, but he had not himself hit upon Darwin's great law of Natural selection. Immediately upon reading the “Origin” he became a disciple. Darwin had said that the allegiance of any considerable number of the older naturalists was too much to expect. But the venerable Lyell, up to that time no evolutionist, who possessed more influence in scientific circles than any other man in England, announced his conversion in a new edition of his "Principles of Geology." A. R. Wallace (who had himself arrived at the theory of natural selection at about the same time with Darwin), Tyndall, Lubbock, and Tyler in England; Asa Gray, Nathanael Shaler, David Starr Jordan, Edward Youmans, and the younger Agassiz in America, all took up the cudgel for evolution.
Divines, and especially theological professors, raised many objections. They were not sure all at once, naturally, where the new thinking might lead in the matter of religion. Some of the things said by them in those early days make interesting reading in the light of some that are being said now. "It is a brutal philosophy,” said Cardinal Manning: “There is no God, and an ape is our Adam.” Bishop Wilberforce in a .
a public speech congratulated himself that he was not
descended from a monkey, which drew from Huxley his famous reply, that if he had to choose he would prefer to be descended from a monkey than from a man who employed his knowledge and eloquence to misrepresent those who were wearing out their lives in the search for truth. The Catholic World declared, "Mr. Darwin is, we have reason to believe, the mouthpiece of that infidel clique whose well-known object is to do away with all idea of God.” Gladstone complained that Darwin had relieved God of all the labor of creation. Dean Burgon declared that the entire scheme of salvation was at stake. And it remained for the Dublin University Magazine to add, “that the new doctrine sought to displace God by the unerring action of vagary." 4 There was one characteristic which all these criticisms shared in common. They were all popular, sentimental, ad hominem in point of view. There was no support of scientific knowledge back of any of them. Therefore they did not halt in the least the trend of thought among scientific men, which went on its way uninterruptedly. Among notable scientific men in America, Agassiz was the only man who held back. Prof. Asa Gray in 1873 could write, “At present we call to mind only two working naturalists who hold to the fixity of species," i.e., who do not accept the Darwinian doctrine in some form. In view of this swift early landslide toward Darwinism in scientific circles, and the present-day application of evolution to so many spheres beyond that to which Darwin applied it, the statement of Mr. Punnett, Professor of Biology in Cambridge University, seems quite within the truth: “ 'The Origin of
See Andrew D. White, Warfare of Science with Theology in Christendom, vol. I, pp. 76–76, for these and other instances.
Species' has influenced human thought more profoundly than any other book of modern times.” The President of the Linnean Society of London declared that “Darwin first taught the world to believe in evolution.” Dr. White also agrees that the date of the reading of Darwin's first paper before the Linnean Society "separates two epochs in the history not merely of natural science, but of human thought."
Darwin occupied such a commanding position for years that it is no wonder the terms evolution and Darwinism were used interchangeably for a while. I Ι shall show in a few moments some points of departure at which evolutionists since Darwin have deviated from his conclusions. I believe these points to be much fewer and of much less consequence than is sometimes assumed. But however much modification the Darwinian statement of evolution may have undergone, no scientific man hesitates a moment over the acceptance of the main thing that Darwin championed. That the world and all the creatures in it have been subject to the law of growth, and have come to be what they are by a process of growth, and not by any sudden creation; that evolution is going on all the time; that as Lyell maintained, the same forces which we see at work worked throughout the past to produce what we now see—there is no more doubt, and no more difference of opinion among scientific men in regard to these things than there is over the law of gravity or the roundness of the earth. It would have been strange if Darwin's work had been without a flaw. But evolution is as universally accepted by the scientific men of the present time as special creation