Note A to Page 57. 



I THINK it is desirable here to adduce one or two concrete 

 illustrations of these abstract principles, in order to show how, 

 as a matter of fact, the structure of Weismann's theory is 

 such as to preclude the possibility of its assumptions being 

 disproved — and this even supposing that the theory is false. 



At first sight nothing could seem more conclusive on the 

 side of Darwinian or Lamarckian principles than are the facts 

 of hereditary disease, in cases where the disease has unques- 

 tionably been acquired by the parents. Take, for example, 

 the case of gout. Here there is no suspicion of any microbe 

 being concerned, nor is there any question about the fact 

 of the disease being one which is frequently acquired by 

 certain habits of life. Now, suppose the case of a man who 

 in middle age acquires the gout by these habits of life — such 

 as insufficient exercise, over-sufficient food, and free indulgence 

 in wine. His son inherits the gouty diathesis, and even though 

 the boy may have the fear of gout before his eyes, and con- 

 sequently avoid over-eating and alcoholic drinking, &c., the 

 disease may overtake him also. Well, the natural explanation 

 of all this is, that the sins of the fathers descend upon the 

 children ; that gout acquired may become in the next generation 

 gout transmitted. But, on the other hand, the school of 

 Weismann will maintain that the reason why the parent 

 contracted the gout was because he had a congenital, or 

 " blastogenetic," tendency towards that disease— a tendency 

 which may, indeed, have been intensified by his habits of 

 life, but which, in so far as thus intensified, was not trans- 

 mitted to his offspring. All that was so transmitted was the 



