INTRODUCTION 7 



But if we owe our existence to the gratification of 

 what may be called our lower instincts, it is no less certain 

 that all that is best in us we owe to our offspring. We 

 meet with the beginnings of altruism, which the begetting 

 of offspring entails, far down in the animal kingdom, 

 and it attains to its full perfection in the human race. 

 Here only, in its best and truest sense. Love begins : 

 though affection may be found, and in a high degree, 

 in many of the lower animals. 



Living things are as clay in the hands of the potter. 

 But it is as if they made themselves, for the designer and 

 the guiding hand are alike invisible. No vessel is exactly 

 like its neighbour, either in the quality of its substance 

 or in the details of its construction. And this because 

 the clay of which it is made possesses that mysterious 

 property we call life. A property which endows each 

 new feature as it appears, with an individuality of its 

 own, whose survival, or suppression, depends entirely 

 on its relationship to surrounding parts ; on its harmony 

 with its environment, in short. Colour, size, shape, 

 temperament, behaviour, may each be regarded as so 

 many entities depending for survival on whether or 

 not they can exist in harmony with their environment — 

 the several parts which make up what we call the 

 individual. 



In Hke manner the individual — the complex bundle 

 of parts and quahties — must attain, and maintain, a 

 certain harmony with its environment — the outer world. 

 The process of change, both in quaHty and quantity, 

 which is for ever going on among the several parts of 

 every separate individual, brings about the elimination 

 of unfavourable variations ; and " selects " those which 

 vary in the right direction : that is to say, which serve 



