To acknowledge the law of heredity with its concomitant scientific implications, must inevitably change our mental outlook in many directions. Accordingly as we relatively place heredity or environment first, our views on social politics will be fundamentally sound or unsound. Taking a large view of society it must make an abysmal difference whether we think the race can or cannot be improved (not merely polished or even enlightened but really changed) by _modifications of environment_. We can no longer pursue the same and by the same means if we come to the conclusion that the individual is either born a potential asset to society or "damned into existence," a permanent drain on his fellows' comfort and wealth, even a possible miasma of infectious criminality. I am a Eugenist because I believe that the nature we have received from hereditary sources transcends in effectiveness all the nurture which follows birth. Eugenics means seeking for facts and applying them to solve the greatest of all problems--looking for light by which the race may control its destiny. Heredity in the animal and vegetable world may be considered dispassionately enough. Geology and astronomy are only hereditary studies affecting the birth of worlds. But from human birth and sex, the mysteries of creation in their divinest form, from _these_ branches of the study of heredity the flaming sword of prudery warns us away. The subject of human sex has been the play-ground of neglect, ignorance, bigotry, superstition, persecution and every other foe to inquiry. It has been the object of worship but not of explanation, of romance but not of science, of abuse, mutilation, misunderstanding, but not of study, reason and generalization. Eugenics of course aims at expressing the scientific side of the process of which love is the artistic. The rare handful of brave men and women who against unique opposition have forced this question to the front are not to be blamed if up to now Eugenics can hardly be said to exist as a systematised science. It is in the nature of things that as a philosophy Eugenics is hardly more than a guess, a probability, an hypothesis. Doubt, uncertainty and half-heartedness inevitably accompany a movement so undeservedly discredited as this has been. Without the means to collect the enormous body of facts required to justify national action the Eugenists have been content to rely upon personal experiences, isolated family histories and the normal and abnormal facts which newspapers, biographies and daily life presented to them. Eugenists have wrestled against difficulties like Hercules in the Augean stable or Paul in the Ephesian arena. In fact the stable and the arena throw more light on Eugenics than any at present available from the human animal. The existent biology of Eugenics means a study of non-human life. There is a sufficiently extensive literature and digest of experiments relating to animal and plant life to serve as the stock in trade of