To put the facts in the form of a truism, part of the children born in any district in a given year are doomed by heredity to an early death; and if they die in one year they will not be alive to die in the succeeding year, and vice versa. Of course there are in addition infant deaths which are not selective and which if prevented would leave the infant with as good a chance as any to live. In the light of these researches, we are forced to conclude that baby-saving campaigns accomplish less than is thought; that the supposed gain is to some extent temporary and illusory. 2. There is still another consequence. If the gain is by great exertions made more than temporary; if the baby who would otherwise have died in the first months is brought to adult life and reproduction, it means in many cases the dissemination of another strain of weak heredity, which natural selection would have cut off ruthlessly in the interests of race betterment. In so far, then, as the infant mortality movement is not futile it is, from a strict biological viewpoint, often detrimental to the future of the race. Do we then discourage all attempts to save the babies? Do we leave them all to natural selection? Do we adopt the "better dead" gospel? Unqualifiedly, no! The sacrifice of the finer human feelings, which would accompany any such course, would be a greater loss to the race than is the eugenic loss from the perpetuation of weak strains of heredity. The abolition of altruistic and humanitarian sentiment for the purpose of race betterment would ultimately defeat its own end by making race betterment impossible. But race betterment will also be impossible unless a clear distinction is made between measures that really mean race betterment of a fundamental and permanent nature, and measures which do not. We have chosen the Infant Mortality Movement for analysis in this chapter because it is an excellent example of the kind of social betterment which is taken for granted, by most of its proponents, to be a fundamental piece of race betterment; but which, as a fact, often means race impairment. No matter how abundant and urgent are the reasons for continuing to reduce infant mortality wherever possible, it is dangerous to close the eyes to the fact that the gain from it is of a kind that must be paid for in other ways; that to carry on the movement without adding eugenics to it will be a short-sighted policy, which increases the present happiness of the world at the cost of diminishing the happiness of posterity through the perpetuation of inferior strains.