MENTAL DEFECT, 



MAL-NUTRITION AND THE TEACHER'S 



APPRECIATION OF INTELLIGENCE 



A REPLY TO CRITICISMS OF THE MEMOIR ON ' THE INFLU- 

 ENCE OF DEFECTIVE PHYSIQUE AND UNFAVOURABLE 

 HOME ENVIRONMENT ON THE INTELLIGENCE OF SCHOOL 

 CHILDREN '. 



In the above Galton Eugenics Memoir, the conclusion 

 was reached that home environment, as measured by 

 clothing, cleanliness, nutrition, stature, and weight, could 

 not be the chief determining cause of the differentiation of 

 intelligence ; nor was defective physique its source. Some 

 contribution unfavourable home environment and defective 

 physique may make to the degree of intelligence, but even 

 if this be finally demonstrated, it will be found to be a 

 ^second order' contribution, possibly even an indirect effect 

 of race and stock, the abler children being those of fitter 

 parents who provide better homes and hand down better 

 physique. Other factors of environment have yet to be 

 discussed, but so far — and this generalization covers much 

 more than the 400 coefficients calculated in the memoir 

 disclose — there is no sign of an environmental condition pro- 

 ducing an effect on the mentality of the child at all com- 

 parable with the known influence of heredity.^ It should 

 be noted also that the purpose of the memoir was twofold : 

 (a) to illustrate the difficulties that arise in attempting to 

 make reliable and comparable observations on school 

 children ; and (d) to indicate the difficulties met with in 



* See A/emozf, p. 60. 

 A 2 



