The present volume seeks to supply what is undoubtedly a real need at the present day--a general introduction to eugenics which is at least considered and responsible. I am indebted to more than one pair of searching and illustrious eyes, which I may not name, for reading the proofs of this volume. My best hopes for its utility are based upon this fact. If there be any other reason for hope it is that during the last six years I have not only written incessantly on eugenics, but have spoken upon various aspects of it some hundreds of times to audiences as various as one can well imagine--a mainly clerical assembly at Lambeth Palace with the Primate in the Chair, drawing-rooms of title, working-class audiences from the Clyde to the Thames. It has been my rule to invite questions whenever it was possible. Such a discipline is invaluable. It gives new ideas and points of view, discovers the existing forms of prejudice, sharply corrects the tendency to partial statement. It is my hope that these many hours of cross-examination will be profitable to the present reader. It has been sought to define the scope of eugenics, and my consistent aim has been, if possible, to preserve its natural unity without falling into the error, which I seem to see almost everywhere, of excluding what is strictly eugenic. Our primary idea, beyond dispute, is selection for parenthood based upon the facts of heredity. This, however, is not an end, but a means. Some eugenists seem to forget the distinction. Our end is a better race. If then, beyond selecting for parenthood, it be desirable to take care of those selected--as, for instance, to protect the expectant mother from alcohol, lead or syphilis--that is strict eugenics on any definition worth a moment's notice. It then appears, of course, that our demands come into contact with those prejudices which political parties call their principles. A given eugenic proposal or argument, for instance, may be stamped as “Socialist” or as “Individualist,” and people who have labelled their eyes with these catchwords, which eugenics will ere long make obsolete, proceed to judge eugenics by them. But the question is not whether a given proposal is socialistic, individualistic or anything else, but whether it is eugenic. If it is eugenic, that is final. To this all parties will come, and by this all parties will be judged. The question is not whether eugenics is, for instance, socialist, but whether socialism is eugenic. I claim for eugenics that it is the final and only judge of all proposals and principles, however labelled, new or old, orthodox or heterodox. Some years ago I ventured to coin the word eugenist, which is now the accepted term. With that label I believe any man or woman may well be content. If this be granted, the old catchwords and the bias they create forgotten, we may be prepared to consider what the scope of eugenics really is.