2 74 THE POPULAR SCIENCE MONTHLY 



the opinion tliat crude elimination does not improve social conditions. 

 I emphasized the contrast between the unit characters of the germ cell 

 and the visible traits observed in men at maturity. If mental and 

 moral traits are predetermined through innate influences^ the visible 

 traits of men can not be altered without corresponding changes in the , 

 germ cell. There must also be as many individual determinants in the 

 germ cell as there are observable traits in men at maturity. In con- 

 trast to this view, I sought to show that single characters might produce 

 a multitude of visible effects, and that the great mass of social and 

 mental traits could be accounted for without assuming a change in 

 many innate characters. 



Most visible traits are modifications in individuals, and not varia- 

 tions in germ cells. Modifications are acquired characters due to the 

 action of the environment, social and physical, which would not appear 

 in children if the environment were radically altered. Chastity, tlirift 

 or temperance might readily be transformed into their opposites with no 

 other changes than the environment imposes. These traits reappear for 

 many generations in certain families, and seem to be inborn, but we 

 have only to make a radical change of environment to see them displaced 

 by their opposites. Civilization and culture perpetuate themselves 

 through the permanence of social and economic conditions. Degenera- 

 tion sets in with any slump of the forces that compel a constant repeti- 

 tion in each generation of the acts and thoughts of their immediate 

 ancestors. 



The eugenist concept of biologic development is that of a multitude 

 of individual characters each of which becomes visible in snecific 

 external traits. Germ-cell changes are presupposed with each change in 

 the statistical averages obtained by the measurement of individual parts 

 or organs. If this be true, statistical evidence based on the measure- 

 ments of individual traits is proof of the presence of a corresponding 

 character in the germ cell, and any variation in the one is evidence of a 

 change in the other. The opposing view assumes that the visible traits 

 usually are modifications due to the action of the environment which 

 are not inherited, but must be reimposed by the action of external con- 

 ditions on succeeding generations. Modifications of this kind do not 

 come singly but in groups. A change of climate or of the food supply 

 is not to be measured by a single change, but by many minor changes 

 that alter all parts of the body. A clear upland climate will give greater 

 vigor. This will result in greater activity through which many struc- 

 tures are altered. These will be followed by changes in habits and 

 customs, creating new traits or changing the relative prominence of old 

 ones. And finally social and political changes occur accompanied by 

 moral and religious modifications. In these ways a complicated net- 

 work of changes arise that are to be referred to ultimate changes in 

 climate, food, health and activity. These causes create types differing 



