PRACTICAL CONSIDERATIONS 



245 



to realise itself in development. Nurture supplies the liberating 

 stimuli necessary for the full expression of the inheritance. A 

 man's character as well as his physique is a function of " nature " 

 and of " nurture." In the language of the old parable of the 

 talents, what is given must be traded with. A boy may be truly 

 enough a chip of the old block, but how far he shows himself such 

 depends on " nurture." The conditions of nurture determine 

 whether the expression of the inheritance is to be full or partial. 

 It need hardly be said that the strength of an (inherited) indi- 

 viduality may be such that it expresses itself almost in the face 

 of inappropriate nurture. History abounds in instances. As 

 Goethe said, Man is always achieving the impossible. Corot was 

 the son of a successful milliner and a prosperous tradesman, and 

 he was thirty before he left the draper's shop to study nature. 



(&) Although modifications do not seem to be transmitted as 

 such, or in any representative degree, there is no doubt that they 

 or their secondary results may in some cases affect the offspring. 

 This is especially the case in typical mammals, where there is 

 before birth a prolonged (placental) connection between the 

 mother and the unborn young. In such cases the offspring is 

 for a time almost part of the maternal body, and liable to be 

 affected by modifications thereof — e.g. by good or bad nutritive 

 conditions. In other cases, also, it may be that deeply saturating 

 parental modifications, such as the results of alcoholic and other 

 poisoning, affect the germ- cells, and thus the offspring. A 

 disease may saturate the body with toxins and waste-products, 

 and these may provoke prejudicial germinal variations. 



(c) Though modifications due to changed " nurture " do not 

 seem to be transmissible, they may be re-impressed on each 

 generation. Thus " nurture " becomes not less, but more, im- 

 portant in our eyes. 



" Is my grandfather's environment not my heredity ? " asks 

 an American author quaintly and pathetically. Well, if not, let 

 us secure for ourselves and for our children those factors in the 



