154 HAECKEL 



But we must understand the thirty-sixth speech 

 if we are to understand the thirty-seventh. 



It was the second sitting, on September 22nd. 

 Virchow spoke on '^the alleged materialism of 

 modern science." The subject was not provoked 

 by Haeckel, but by Schleiden, the botanist, the 

 parent of the cell-theory. The controversy over 

 materialism had raged furiously for many years. 

 We need only mention Biichner (whose Force and 

 Matter appeared in 1855) and Carl Vogt. There 

 was an element of necessity, but a good deal of 

 superficiality in the controversy, as it was then 

 conducted. Friedrich Albert Lange has given us 

 a masterly history of it. At this moment it was 

 particularly instructive to point out the difference 

 between general philosophical skirmishing with 

 words and a really able piece of work that, though 

 it had a technical look, suddenly added a new 

 province to philosophy on which every doubting 

 Thomas could lay his hands. However, Schleiden 

 had not advanced. Curiously enough, he, the 

 first discoverer of the cell, attacked Virchow's 

 theory of man as a cell-state as a typical materialist 

 extravagance. 



He had published a heated essay, and Virchow 

 defended himself. He gave such a remarkable 

 and characteristic expression of his inmost feelings 

 that it is worth while disinterring it. It is a very 

 rare thing for a thoughtful man to give a natural 

 philosophical speech that begins with crystalline 

 clearness of logic and then makes a most curious 

 salto mortale at the critical point. 



