346 Heredity. 



mental and executive agreement of the will. For all these reasons 

 they are personal they depend on free-will, and are not hereditary.' 



The second case is that in which inherited tendencies possess 

 an irresistible character. Not to speak of those states of well- 

 defined insanity in which the individual is alienus a se, where per- 

 sonality disappears, assailed and finally overcome by fatal impulses 

 or fixed ideas, we have seen indisputable cases where the tendency 

 to vice and to crime is a heritage which descends with the cer- 

 tainty of fate. The personal factor has then no strength to react 

 against these interior impulses. Let the reader recall the many 

 instances of this kind cited under the head of Heredity of Senti- 

 ments and Passions. In such cases there is no responsibility. 



In this unceasing conflict which goes on within us between 

 individual and specific characteristics, between personality and 

 heredity, and, in more general terms, between free-will and fate, 

 free-will is more frequently overcome than is commonly supposed. 

 But this is often not admitted, and as Burdach well observes, with 

 the excellent intention of proving to man that he is free, we too 

 often forget 'that heredity has actually more power over our 

 mental constitution and our character than all external influences, 

 physical or moral.' This we shall now see under another form, 

 when we inquire into the relations between education and heredity. 



ii. 



Great stress has recently been laid on the influence of the 

 physical environment. It has been shown how the climate, the 

 air, the character of the soil, the diet, the nature of the food 

 and drink all that in physiology is comprised under the tech- 

 nical terms drcumfusa, zngesta, etc. shape the human organism 

 by their incessant action ; how those latent, silent sensations which 

 do not come into consciousness, but still are ever thronging the 

 nerves of sense, eventually form that habitual mode of the con- 

 stitution which we call temperament. 



The influence of education is analogous. It is a moral environ- 

 ment, and its result is the creation of a habit. We might even 

 affirm that this moral environment is as complex, as hetero- 

 geneous and changeable, as any physical environment For 



