The argument assumes that conscience or the desire for children (no matter which) is hereditary--but hereditary only in the most general formal sense. The result will be the same whether the attitude is transmitted through germ cells, or exosomatically, to use A. J. Lotka's term. (If one denies the latter possibility as well as the former, then what's the point of education?) The argument has here been stated in the context of the population problem, but it applies equally well to any instance in which society appeals to an individual exploiting a commons to restrain himself for the general good--by means of his conscience. To make such an appeal is to set up a selective system that works toward the elimination of conscience from the race.