In order to discuss the economic factors affecting the propagation of different types of men it may be well to divide the population roughly into three classes: the well-to-do at one extreme, those in actual want at the other, and the vast intermediate class who come under neither description. Such a division is arbitrary, but may serve to indicate certain influences bearing upon our question. Let us include in the first, families whose income is $2,000 or more, in the second, those whose income is less than $600, and in the third, families whose income is between these amounts.[54] The first class is the successful class, judged by pecuniary standards, and includes not only prosperous business men, but the better paid of the professional class, and of men living on salaries. The prevailing tendency in this part of society, subject of course to many exceptions and modifications, appears to be to sacrifice the size of the family to other interests. This is the class which easily forms habits of luxury, and develops costly and exacting ideals regarding the nurture and education of its children. For the money spent upon them no pecuniary return is expected, and the hardship and responsibility inseparable from the rearing of a family appear greater by contrast with habits of ease. It is also in this class that personal choice is most cultivated, and the sophistication that applies this to limiting the number of children, so that, although the death-rate is low, the birth-rate is scarcely sufficient to offset it. Relatively to other and more prolific parts of the population the stocks represented in this class may be regarded as tending to decline.[55] The biological significance of this depends upon the value of these stocks, upon what distinctive biological traits, if any, are to be found in well-to-do families as a group. The prevalent view among eugenic writers, led by Galton, has been that the successful class, on the whole, represents the ablest stocks, and that eugenic progress depends mainly upon securing a high rate of increase among them. Galton himself held that all other eugenic aims were of secondary importance. It should be noted, however, that he did not propose to measure success merely by income, but rather by established reputation among the group best able to judge of a particular kind of merit. His eugenic aristocracy would consist, for example, of those lawyers, artists, men of letters, men of science, and even of those skilled artisans, who are regarded by their colleagues as able men of their kind. The business group would no doubt be included but would not be allowed an importance at all corresponding to its wealth. At the apex of this aristocracy would be men of genius, the test of genius being great and enduring reputation.[56]