6 An Examination of Weismannism. 



the result of accident or disease. Now, in the former 

 case — i.e., in that where the malformation is con- 

 genital — it is extremely probable that the peculiarity 

 will be transmitted to his children ; while in the latter 

 case — i.e., where the malformation is subsequently 

 acquired — it is virtually certain that it will not be 

 transmitted to his children. And this great difference 

 between the transmissibility of characters that are 

 congenital and characters that are acquired extends 

 universally as a general law throughout the vegetable 

 as well as the animal kingdom, and in the province of 

 mental as in that of bodily organization. Of course 

 this general law has always been well known, and 

 more or less fully recognized by all modern physi- 

 ologists and medical men. But before the subject 

 was taken up by Professor Weismann, it was generally 

 supposed that the difference in question was one of 

 degree, not one of kind. In other words, it was 

 assumed that acquired characters, although not so 

 fully — and therefore not so certainly — inherited as 

 congenital characters, nevertheless were inherited in 

 some lesser degree ; so that if the same character 

 continued to be developed successively in a number 

 of sequent generations, what was at first only a slight 

 tendency to be inherited would become by summation 

 a more and more pronounced tendency, till eventually 

 the acquired character might be as strongly inherited 

 as any other character which was ab initio congenital. 

 Now it is the validity of this assumption that is 

 challenged by Professor Weismann. He says there is 

 no evidence of any acquired characters being in any 

 degree inherited ; and, therefore, that in this important 

 respect they may be held to differ from congenital 



