Foreword 



It is very important that all parents, all 

 teachers, and all physicians should understand 

 the interlocking relations of heredity and en- 

 vironment. So much reliance is placed on ed- 

 ucation in America that it is necessary to 

 stress the great importance of being born with 

 a sound and healthy constitution and with good 

 moral, spiritual, and intellectual predisposi- 

 tions. 



Heredity is, in fact, altogether a matter of 

 predisposition and potentiality; it is the key 

 which fits the lock t)f environment, including 

 all the steps in nurture and in education. Con- 

 sequently, eugenics, which has to do with be- 

 ing born well, and euthenics, which has to do 

 with being nurtured and educated well, have 

 been inseparable from the beginning of time. 



The value of a clear understanding of these 

 principles to the parent, teacher and physi- 

 cian, begins with birth and extends through 



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