DARWIN AND NATURAL SELECTION 45 



vention? For the only point at issue was the prin- 

 ciple of descent; the theory of natural selection was 

 indeed invaluable, for it explained the very processus 

 of descent. Whatever may befall this theory in the 

 future, whether it is to be superseded by some other 

 theory or not, Darwin's everlasting title to glory will 

 be that he explained the seemingly marvellous adap- 

 tation of living things by the mere action of natural 

 factors, without looking to a divine intervention, with- 

 out resorting to any finalist or metaphysical hypothe- 

 sis. 



What is the real meaning of "natural selection," of 

 the. "struggle for life," two well-known terms which 

 have been used too frequently, especially outsideef 

 the limits of biology? 



As more living things are born, according to Mal- 

 thus, than the earth can support, there arises between 

 them a competition for food and better condTtTons, 

 a struggle whose outcome depends upon the superior 

 advantages which certain individuals possess over cer- 

 tain others. This inequality is unavoidable, for even 

 the young born from the same parents always pre- 

 sent marked differences. That fact is even more fre- 

 quently observed between individuals merely of the 

 \ame species. Those distinctive characters are gen- 

 erally superficial and not very noticeable but they are, 

 nevertheless, either useful or harmful to the individ- 

 ual. If useful, they impart to it a superiority over 



