PAPERS OX PSYCHOLOGY AND EDUCATION 479 



the other twenty percent is distributed thruout the re- 

 mainder of life. He observed, too, that the adult is ap- 

 parently an entirely different creature mentally than the 

 child of seven, and he was led to ask whether this small 

 percent of growth might not be of such difference in 

 quality as to bring about this result, forgetting the effect 

 of training which, in standardized and formal ways, be- 

 gins at seven. The further researches of Donaldson and 

 his students indicate that brain growth ceases at a much 

 earlier age than seven. 



If the term intelligence connotes this innate capacity 

 related to neural growth, then development ceases at this 

 early age and not at thirteen or sixteen. If intelligence 

 connotes the results of training and formal education in 

 addition to innate structure, then it probably ceases only 

 with senility. The average child of thirteen has, for ex- 

 ample, a certain knowledge of mathematics, namely arith- 

 metic. In high school he makes a readjustment of this 

 knowledge to fit more complex forms, algebra and ge- 

 ometry, which in turn are capable of further readjust- 

 ment into the more complex forms of college mathematics. 

 He has a certain rather simply organized body of histor- 

 ical knowledge, United States history, which is further 

 evolved into high school and college history. He has 

 certain vocabularies which are increased quantitatively 

 and qualitatively by the new terms of the new sciences 

 and literatures of the higher schools. TVhen our psy- 

 chologists declare that mental development of the race 

 stops at a certain point as measured by certain scales, 

 would it not be well to analyze those scales before assum- 

 ing that fifty percent of the race is innately inferior? 

 Might we not ask how much of the test is the result of 

 formal training which for the greater part ceases at 

 thirteen? More mathematics "will not help us here. This 

 attitude is supported by Freeman and others who have 

 maintained that the flattening of the curve of mental 

 growth at the adolescent period is due to the character of 

 the test and not to a phase of development. 



The problem of maturity of development at any age is 

 a variation of the problem of limit of development. That 

 there is a quality due merely to having lived at all. which 



