396 THE POPULAR SCIENCE MONTHLY 



THE LAWS OF EXVIEOXMENTAL INFLUENCE 



By Peofessob SIMON N. PATTEN 



UNIVERSITY OF PENNSYLVANIA 



THE relation of environment to heredity presents an issue that is 

 becoming increasingly clear. I will state it in the words of Dr. 

 F. A. Woods. " Experimentally and statistically, there is not a grain 

 of proof that ordinarily environment can alter the salient mental and 

 moral traits in any measurable degree from what they were predeter- 

 mined to be through innate influences." x The premises of this state- 

 ment lie in biology, while the conclusions must be verified by facts in 

 social science. Dr. Woods implies that, for each virtue society holds 

 dear and for each vice it condemns, there is a biologic character without 

 the presence of which the virtue or the vice could not appear. This 

 position controverts the evidence of social science as to the basis on 

 which virtues and vices rest. 



To discuss this problem, I must begin with the difference between 

 the data of social and biologic sciences. Biology uses experiment and 

 hence begins with germ cells : social science is based on observation and 

 hence its data are the visible differences which the study of men affords. 

 Both call their data characters, but as a loose terminology creates con- 

 fusion, I shall call the germinal variations the biologist finds through 

 experiment characters, while the visible differences in men open to ob- 

 servation I shall call traits. The problem then is what is the relation of 

 biologic characters to visible traits ? Is there a character for each trait, 

 or do independent laws govern traits? To answer these questions, 

 traits must be divided into two classes; mental traits are measured by 

 differences in thought and expression while bodily traits denote external 

 differences. Mental traits are again divided into social traits, which are 

 impressed on individuals by society and physical traits which reflect 

 brain activity. 



Physical traits do not correspond to the virtues and vices emphasized 

 by society. There are only five that have social significance — imitation, 

 suggestion, sympathy, self-interest and will power. These have biologic 

 antecedents. Social traits, however, change from environment to 

 environment, from group to group and even from family to family. 

 They are readily adopted, easily lost and have the marks of acquired 

 characters. The motives for adopting a virtue come to the individual 

 through social influences. The power in him leading to its acceptance is 

 not due to some unit-character corresponding to the virtue in question, 



1 The Popular Science Monthly, April, 1910. 



