2 THE FIRST PRINCIPLES OF HEREDITY 



possession of a few trained specialists. The public at large 

 takes no notice of it, or, if at all, talks humorously of it, as 

 of yore, without recognizing man's great responsibility to 

 the future. 



In our own days, when the social question has come so 

 prominently to the front, and every consideration is given 

 to the reconstruction of the material basis of society, far too 

 little attention is given to the integral unit of society, the 

 individual, and his connection with society. Evolution has 

 taught us to regard society as a whole, to look on the ever- 

 changing procession of generations as a long interconnected 

 chain, where each link is shaped and influenced by its pre- 

 decessor, determining in its own turn the nature of the next 

 link. What is the extent of this influence ? What are the 

 forces at work ? What the consequences ? These ques- 

 tions are not mere idle speculations of a curious mind 

 engaged in professional specialism. The consideration of 

 the constitution of each individual enters into the calcula- 

 tion of his social fitness, concerns the welfare of each and 

 all, and has therefore to be considered a right and proper 

 subject for earnest attention, and not to be overlooked or 

 contemptuously brushed aside. 

 ^ A new era has dawned upon the civilized world. The 

 idea of evolution has changed the whole aspect of the 

 human horizon. We are no longer satisfied with the old 

 homely truths, mere guesses at the destination of man ; 

 but, having lifted somewhat the veil of Nature's purpose, 

 having learnt a little of man's beginning and his develop- 

 ment, we have set ourselves seriously to the task of working 

 out our destiny, consciously, and not blindly, as hitherto. 



Social Science, rightly understood, is based on two 

 factors : Heredity and Evolution, i To understand the 

 world's progress from the new standpoint, and to get a 

 complete grasp of the facts and theories involved ; to be 

 able to form a judgment and add one's little share to the 

 future of mankind ; it is absolutely necessary to make one- 

 self acquainted with the problems of modern Biology, as 



