“educability” to a degree which varies in every family and race. To estimate correctly, and so to deal with these various factors in human life, we require to know in detail the laws of breeding, heredity, variation, and selection in animals, and, further, the laws or formulated results of enquiry as to the “educability” of the human being, the range and the limits of “education,” the relation of hereditary quality to education, the causes of mental aberration and defect, of mental qualities of all kinds, the value and the dangers of all kinds of educational influences, whether physical, social, or intellectual. These are matters in regard to which there must be in the future more and more of common knowledge and agreement; at present they are lightly touched by politicians and journalists in a way which is inconsistent with a knowledge of the facts or of their importance. When publicists airily declare that the virtues of kings and the vices of paupers are both due to the hereditary transmission of characters acquired by the peculiarities of diet and exercise of the progenitors of these classes it is time to protest. To cite the name of Darwin and “the laws which govern animal and plant life,” in support instead of in condemnation of such baseless fancies, is, one must suppose, an evidence, not of a desire to mislead, but of a regrettable indifference to the conclusions of that branch of human knowledge which is of more importance than any other to the statesman and the philanthropist. “Selection,” whether due to survival in the struggle for existence or exercised by man as a “breeder” or “fancier,” is the only way in which new characteristics, good or bad, can be implanted in a race or stock, and become part of the hereditary quality of that race or stock. This applies equally to man and to animals and plants. And this selection is no temporary or casual thing. It means “the selection for breeding” of those individuals which spontaneously by the innate variability which all living things show (so that no two individuals are exactly alike) have exhibited from birth onwards, more or less clearly, indications of the characteristic which is to be selected. Nothing done to them after birth, and not done to others of their family or race, causes the desired characteristic; it appears unexpectedly, almost unaccountably as an in-born quality. It may be a slight difference only, not easy to take note of; but if it enables those who possess it to get the better of their competitors in the struggle for life, they will survive and mate and so transmit their characteristic to the next generation, whilst those who do not possess it and are beaten in life and fail to obtain food, safety, and mates, will perish and disappear, and their defective strain will perish with them. 37. _Variation and Selection Among Living Things_