Origin of Species.
While these problems and their numerous side issues were being discussed, the scientific world was startled by the publication of Charles Darwin's Origin of Species (1859). In this work the author advocated with singular completeness and ability, that the various species of plants and animals now extant and being continued by the ordinary law of generation, had been derived from pre-existing forms by secondary causes— a process which he designated under the name of Natural Selection. In this manner Mr Darwin traced the origin of man through a series of intermediate forms back to protoplasm, without the intervention of repeated cataclysms and special creative dramas, as were generally held by the earlier geologists. "As all the living forms of life," he writes, "are the lineal descendants of those which lived long before the Cambrian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world." (Origin of Species, p. 428.)
Like all the profound secrets of Nature, the grandeur of Mr Darwin's conception lay in the simplicity and transparency of its truth ; and as a small particle leavens the mass, so the words "struggle for existence" and "survival of the fittest" set the whole philosophical world into a ferment. Indeed, it is impossible to exaggerate the profound effect produced on his fellow-men by the doctrine thus taught by Mr Darwin. Many of the greatest naturalists of the day at once discarded their former creeds, and adopted the evolution theory of life ; and at the present time it may well be asked who and where are its opponents !
Of all the thinking men who adopted the evolution theory of man's origin, Huxley takes the foremost place.
By the publication of his three famous lectures on Man's Place in Nature (1863), he finally shattered the hypothesis which assigned man's origin and civilisation to a sui generis code outside the ordinary laws of the organic world. These are a few of the scientific facts and speculations which loomed on the philosophical horizon when the theory of man's natural
