Abstract

PIP: The attempt is made to describe and analyze the way in which mental ability, physical size, and social circumstances are related in children and adults. This example is used to develop the thesis that is exactly at the interphase of heredity and environment that positive eugenices may make a significant impact. The belief is that the positive eugenists attention should be directed at providing the environmental stimuli most appropriate to evoke and derive from each zygote those potentialities which would best enrich and humanize the culture. Focus is on body size and mental ability, the number of children in the family, occupational or socioeconomic class, social stratification and the steady state. Among children of school age there is a significant but low correlation between body size and scores in various tests of ability and attainment, such that larger children score more highly than children of the same age. This correlation diminishes when maturity is reached, but it does not totally disappear. The greater the number of chidlren in the family the lower their height and the less their scores in mental tests. There are also differences in height and mental ability between children in different socioeconomic groups and these persist to a degree into adult. Taller women tend to rise in the social scale, both in getting jobs and in marriage, while shorter women, on average, tend to sink. It is not known in what proportions heredity and environment contribute to these effects.