The view will ultimately prevail that the strong only are of value to society, and that every weak member of the community involves a definite social loss. It will be generally understood that large families are not advantageous, inasmuch as it is not quantity but quality that really matters. The day will come in which fatherhood and motherhood will be permitted only to the strong, and in which every endeavour will be made to prevent the birth of diseased and weakly individuals. As far as the “protection” of a great many children is concerned, the method that will be adopted will be to prevent their ever coming into the world. In the future, we shall know better than we know to-day which children are competent to grow up into useful members of society; and those buds which fail to attain this standard will be pruned away. Beyond question, it will not be long before it will be generally understood that the proper application of eugenist principles to the human species will be secured, not so much by coercion, as by enlightenment. But for this very reason it will become of enormous importance to popularise the elements of educational science and of the hygiene of childhood, to effect the sexual enlightenment of children and of adults, and to secure the diffusion of sound ethical ideas. It will be taught that actions injurious to the interests of future generations are immoral, and some of them will even be made punishable offences. Steps will also be taken to ensure as far as possible that only those individuals shall marry whose offspring may be expected to be healthy. In regard to all these problems, the acquirements of medical science are of enormous importance; for it is upon the acquirements of positive science that legislation dealing with such matters must be based. Unfortunately, however, the medical science of our own day is not always in a position to give a decisive and satisfactory answer in respect of the various problems just stated; and suitable legislation on these matters must be deferred to the future, when guidance may be anticipated from the inevitable progress of medical science. _Inheritance and Education._--In human beings, as in other animals, an improvement in the inborn capacities is possible. At the present time we are content to take children as we find them, and we simply endeavour by education to make every child into a useful member of society. But only through influences affecting hereditary qualities can the material of future generations be improved, and a humanity be brought into being better equipped than we are for the tasks of civilisation. Enduring human progress can be effected only by the simultaneous study and application of the laws both of education and of heredity. As by selection the hereditary equipment is improved, the limits of what is attainable by means of education will also be extended.