THE DOCTRINE OF DESCENT. 21 



political life in Berlin than he formerly did by his 

 theoretical scientific work in "Wiirzburg, that is his 

 affair ; but for all that, in his former sphere he was 

 incomparable, and cannot be replaced ; in the latter 

 this is not the case. 



If a distinguished man, be he never so remarkable 

 for uncommon power of work and universal gifts, 

 passes the whole day in the friction of political party- 

 struggles, and throws himself as well into all the petty 

 and wearisome details of daily civic life, it is impossible 

 for him to maintain the requisite feeling for the pro- 

 gress of science particularly when it advances so 

 rapidly and incessantly as is the case in our day. It 

 is therefore quite intelligible that Virchow should soon 

 have lost this feeling, and in the course of the last two 

 decades have become more and more estranged from 

 science. And this estrangement has at last led to so 

 complete a change in his fundamental views, to such 

 a metapsychosis, that the present Virchow of 1878 

 is hardly in a position to understand the youthful 

 Virchow of 1848. 



We have seen a similar mental change occur con- 

 temporaneously in our greatest naturalist, Carl Ernst 

 von Baer. This gifted and profound thinker and 

 biologist, whose name marks a new epoch in the 

 history of evolution, had in his later years become 

 wholly incompetent even to understand those most 



