The entire field of race betterment and social improvement is divided between eugenics, which considers only germinal or heritable changes in the race; and euthenics, which deals with improvement in the individual, and in his environment. Of course, no sharp line can be drawn between the two spheres, each one having many indirect effects on the other. It is important to note, however, that any change in the individual during his prenatal life is euthenic, not eugenic. Therefore, contrary to the popular idea of the case, the "Better Babies" movement, the agitation for proper care of expectant mothers, and the like, are not directly a part of eugenics. The moment of conception is the point at which eugenics gives place to euthenics. Eugenics is therefore the fundamental method of human progress, euthenics the secondary one; their relations will be further considered in the last chapter of this book.