Darwinism stated by Darwin himself · Charles Darwin
“GROUNDS THAT WILL NEVER BE SHAKEN.”
The main conclusion here arrived at, and now held by many naturalists who are well competent to form a sound judgment, is that man is descended from some less highly organized form. The grounds upon which this conclusion rests will never be shaken, for the close similarity between man and the lower animals in embryonic development, as well as in innumerable points of structure and constitution, both of high and of the most trifling importance--the rudiments which he retains, and the abnormal reversions to which he is occasionally liable--are facts which can not be disputed. They have long been known, but until recently they told us nothing with respect to the origin of man. Now, when viewed by the light of our knowledge of the whole organic world, their meaning is unmistakable. The great principle of evolution stands up clear and firm, when these groups of facts are considered in connection with others, such as the mutual affinities of the members of the same group, their geographical distribution in past and present times, and their geological succession. It is incredible that all these facts should speak falsely. He who is not content to look, like a savage, at the phenomena of nature as disconnected, can not any longer believe that man is the work of a separate act of creation. He will be forced to admit that the close resemblance of the embryo of man to that, for instance, of a dog--the construction of his skull, limbs, and whole frame on the same plan with that of other mammals, independently of the uses to which the parts may be put--the occasional reappearance of various structures, for instance of several muscles, which man does not normally possess, but which are common to the Quadrumana--and a crowd of analogous facts--all point in the plainest manner to the conclusion that man is the co-descendant with other mammals of a common progenitor. THE EXPRESSION OF THE EMOTIONS IN MAN AND OTHER ANIMALS. _The subject is treated under three Principles: the Principle of Associated Habit; the Principle of Antithesis; and the Principle of the direct action of the nervous system independent of Will and Habit._
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