The Theory of Natural Selection. 263 



hereditary transmission of what are called congenital 

 characters. And this is all that Darwin's theory 

 necessarily requires. 



The fourth fact is, that although heredity as a whole 

 produces a wonderfully exact copy of the parent in 

 the child, there is never a precise reduplication. Of 

 all the millions of human beings upon the face of the 

 earth, no one is so like another that we cannot 

 see some difference ; the resemblance is everywhere 

 specific, nowhere individual. Now this same remark 

 applies to all specific types. The only reason why 

 we notice individual differences in the case of the 

 human type more than we do in the case of any other 

 types, is because our attention is here more incessantly 

 focussed upon these differences. We are compelled 

 to notice them in the case of our own species, however 

 small they may appear to a naturalist, because, unless 

 we do so, we should not recognise the members of our 

 own family, or be able to distinguish between a man 

 whom we know is ready to do us an important service, 

 and another man whom we know is ready to cut our 

 throats. But our common mother Nature is able 

 thus to distinguish between all her children. Her 

 eyes are much more ready to detect small individual 

 peculiarities than are the eyes of any naturalist. No 

 slight variations in the cast of feature or disposition 

 of parts, no minute difference in the arrangement of 

 microscopical cells, can escape her ever vigilant 

 attention. And, consequently, when among all the 

 innumerable multitudes of individual variations any 

 one arises which — no matter in how slight a degree — 

 gives to that individual a better chance of success in 

 the struggle for lite, Nature chooses that individual 



