As for man, the creature most interesting to us, in what category does he fall? Is he a being whose nature is in harmony with the conditions in which he has to live, or is he out of harmony with his environment? A critical examination is needed to answer these questions, and to such an examination the pages to follow are devoted. CHAPTER III SIMIAN ORIGIN OF MAN Relationship of the human species with anthropoid apes—Analogies in the dentition, in the organisation of the limbs and of the brain—Resemblance of the vermiform appendage of man and anthropoids—Analogy between the placenta and fœtus of man and anthropoid apes—Blood relationship of man and monkeys shown by serums and precipitates—Transmutation of species—Sudden transition from monkey to man—J. Inaudi, the calculator, as an example of the sudden appearance of characters in the human species—Rudimentary organs in man—Proportion of progressive and retrogressive organs in the organisation of man To understand human nature it is necessary first to give an account of the origin of man. This question has preoccupied mankind for ages, and for a long time it was believed that a solution of the problem was to be found in religious dogmas. Man was regarded as being of supernatural origin, the result of a special creation. Scientific criticism has now shown that there are no grounds for such a conclusion. Nearly half a century ago Darwin applied to man his discovery of the principle of natural selection, and of the part played by that in the origin and transmutation of species. Soon after the publication of the “Origin of Species,” attention was given to the special case of man. In 1863 Huxley[48] gave an admirable review of the problem in his work on “Man’s Place in Nature.” He brought forward arguments of the highest scientific validity in support of the thesis that man is descended from animals, and that he is a mammal most nearly related to monkeys, and among these to the anthropoid apes. In spite of this masterly exposition, there are still persons of high intelligence and superior education who declare that science has not yet answered the question as to whence he came, and that the theory of evolution will never provide an answer.[49] Close examination of the structure of man has proved, in the most definite fashion, the existence of a near kinship with the higher monkeys, or anthropoids. When the chimpanzee and the ourang-outang were discovered, comparison became inevitable, and many naturalists, including the great Linnæus, saw that the human race must find its place in classification near the anthropoids.