Eugenics rests on two axioms so simple that a child can understand them. If a people is to survive, it must produce in each year, or each generation, enough children to take the places of those who die during that period. And if it is to avoid deterioration which would also prevent survival, it must encourage childbearing from the part of the population that is, in general, fit, rather than predominantly from the mentally diseased, the mentally deficient, and the physically defective. How can education favor these two necessary conditions of national existence? i. Young people must be educated to choose their mates wisely. This involves the building up of right attitudes from infancy onward; and it also involves some information concerning heredity. With nearly IO per cent of the whole population destined to break down from mental disease at some time during life, with about 5 per cent of the population so lacking in abstract intelligence that it has an I.Q. of 70 or less, and with widespread physical defects, it is important that accurate knowledge concerning the inheritable factors be widespread. This is needed both to discourage unwise matings and to prevent overanxiety and needless fears. Not later than the junior high school, it should be possible to give pupils some sound ideas about heredity, incidentally, in connection with many of the courses in the present curriculum. If such knowledge is to be used, frankness and honesty about one's own family must become somewhat more customary. There is a widespread tendency to feel that concealment or misrepresentation of unpleasant facts in one's ancestry is entirely legitimate. Not merely must a more objective attitude be encouraged, but ways must be found to make family histories more public. Such