Starch: Inheritance of Mental Traits 



95 



Similar work by E. L. Earle is ex- 

 plained. The conclusion of this inves- 

 tigator was that "abilities in special 

 subjects are inherited, apparently to 

 no greater extent in one subject than in 

 another. What is probably inherited 

 is either general scholarship or else 

 more specialized traits than ability in 

 arithmetic, or ability in language. Each 

 study involves many mental faculties 

 and nearly all studies involve the same 

 faculties with varying emphasis. 



'There is no evidence, at least from 

 these figures, for the notion that special 

 abilities in certain studies run in fam- 

 ilies. Mental traits running in families 

 are very likely more specialized than 

 abilities in school studies which involve 

 large groups of mental functions. 

 The children of any given family 

 are on the average equally good or 

 equally poor in all studies. Ability in 

 school work is apparently inherited to 

 the same extent as physical features, 

 since the coefficients of correlation for 

 children of the same parents are 

 approximately the same for both physi- 

 cal and mental traits." 



The study of 185 pairs of sibs in the 

 University of Wisconsin, made by Miss 

 Emily S. Dexter, showed a resemblance 

 of about . 60 in scholarship records in 

 various subjects. Her judgment is 

 "that inheritance, to a much greater 

 extent than training, is responsible for 

 the degree of resemblance found . ' ' One 

 of the bases of this judgment is that 

 sibs of opposite sex were found to be 

 more closely correlated than those of 

 the same sex. 



Several other studies of this sort, 

 and the familiar studies of twans by 

 Francis Galton and by E. L. Thorndike 

 are also cited. 



EFFECTS OF PRACTICE 



2. The influence of uniform environ- 

 ment upon different original abilities 

 has been measured by various psy- 

 chologists. "All experimental results 

 point in the direction that practice does 

 not equalize abilities," Dr. Starch de- 

 clares. "In fact, equal practice tends 

 to increase differences in achievement 

 and skill rather than to decrease them. 

 The more gifted individuals profit 



more, both relatively and absolutely, 

 than the less gifted. This experimen- 

 tal fact is one of the most profound bits 

 of evidence regarding the whole prob- 

 lem of heredity and environment. The 

 talented men not only start with 

 greater initial capacities but seem also 

 to be capable of more intense applica- 

 tion and more zealous desire to im- 

 prove. 'To him that hath shall be 

 given' is psychologically true in the 

 sphere of intellectual training as well 

 as in the sphere of morality and 

 religion." 



"If we may generalize for life as a 

 whole, equal opportunities for all do 

 not produce equal abilities in all. Men 

 may be born free politically; but they 

 p-e not born equal mentally; they may 

 born equal in opportunities in a 

 aemocratic society, but they certainly 

 a...' not equal in their ultimate achieve- 

 ments in life." 



3. Influence of different environ- 

 ments upon various original abilities 

 has likewise been tested by more or less 

 exact methods on many different occa- 

 sions. Dr. Starch considers these studies 

 somewhat uncertain in interpreta- 

 tion; they can be made to prove any- 

 thing. He has, however, ignored one 

 of the strongest pieces of evidence un- 

 der this head, which is a matter of 

 every-day observation — namely, the 

 persistence of inherited qualities in 

 brothers and sisters who are brought 

 up in widely separated surroundings. 

 The case is the more striking if twins 

 are studied. 



Indeed, it is easily possible by more 

 methodical classification of the data 

 available to make out a much stronger 

 case for heredity than Dr. Starch has 

 done. His case, however, is strong 

 enough to make him say : 



THE CONCLUSION 



"The general impression frorti all ex- 

 perimental, statistical, and historical 

 material thus far accumulated on the 

 problems of mental heredity would 

 seem to be somewhat as follows: 

 Barring paupers, invalids, and those 

 suffering from want of food and shelter 

 due to conditions beyond their personal 

 control, and referring to all others liv- 



