198 CONTEMPORARY SCIENCE 



The letter grades which are in use are defined as fol- 

 lows : A designates very superior intelligence ; B, superior 

 intelligence ; C -f-, high average intelligence ; C, average 

 intelligence; C , low average intelligence; D, inferior 

 intelligence; D , very inferior intelligence. The letter 

 E has been reserved for the designation of men whose 

 mental ability is seemingly inadequate for regular military 

 duty. 



Commissioned officers usually possess and obviously 

 should possess A or B intelligence. Many excellent non- 

 commissioned officers possess C or C -(- intelligence, but in 

 the main this group is composed of men with C-f- or B 

 ratings. The great body of privates grades C. Men with 

 D or D intelligence are usually slow to learn and rarely 

 gain promotion. Many of them, especially the D in- 

 dividuals, cannot be used to advantage in a military emer- 

 gency which demands rapidity of training. The results 

 of army mental testing indicate that the majority of D 

 and E soldiers are below ten years mental age. A few 

 fall as low as three or four years. 



The contrast between A and D intelligence becomes 

 impressive when it is shown that men of A intelligence 

 have the requisite mental ability to achieve superior rec- 

 ords in college or professional school, whereas D in- 

 dividuals are rarely able to pass beyond the third or 

 fourth grade of an elementary school, however long they 

 may attend. 



Reliability of Methods. The methods of mental exam- 

 ining used in the army have been found to possess relia- 

 bility as well as practical value which far exceeded the 

 expectations of the men who are responsible for them. 

 Indeed, the success of this particular methodological 

 undertaking is a remarkable demonstration of the "fe- 

 cundity of aggregation." It is extremely unlikely that 

 any individual working alone would have developed 

 within reasonable time equally valuable methods of group 

 examining. Inasmuch as reliability is of first importance, 



