MODERN BIOLOGY 507 



for the enlightened minds of classical antiquity and hatred against the 

 ecclesiastical reaction — a very common trend of thought at that time — 

 which found expression in many quarters in literature, as, for instance, in 

 the works of Haeckel's contemporary fellow-countryman Paul Heyse. His 

 biographers declare that Haeckel's religious change of front took place in 

 the course of spiritual struggles, but there is little trace of them in his letters; 

 it would appear more likely that with him, as with countless others, reli- 

 gious free-thinking was induced by political independence of thought; it 

 w^as difficult in those days to reconcile Christian belief and political liberal- 

 mindedness, owing to the Church's intimate connexion with the reactionary 

 forces in society and her obstinate resistance to all movements of reform. 

 Through his free-thinking, however, Haeckel lost that conviction which 

 had kept him going before, and he felt himself beginning to doubt the possi- 

 bility of penetrating any deeper into the essence of natural phenomena. 



Haeckel embraces Danvinism 

 That guiding line for his thoughts which he thus lost Haeckel rediscovered 

 when he made the acquaintance of Darwin's theory. In Germany as in Eng- 

 land this theory had been received with mixed feelings; instances of this 

 have been given above. Haeckel at once became an ardent supporter of the 

 new doctrine; in it he found not only the means to understand existence, 

 but also the confirmation of the progress he desired to find in it. It was 

 mainly through his promulgation of it that Darwinism became a watch- 

 word for all supporters of the idea of a liberal-minded development in the 

 sphere of social and cultural life, and obviously an abomination to its op- 

 ponents, the clerical and conservative elements in the community. The course 

 of social development in Germany took an unexpected turn, however; the 

 unification of the country, the long-cherished dream of the free-minded, was 

 brought to reality through Bismarck, but in such a manner that the power 

 of the princes and the junkers was preserved. It was not thus that the lib- 

 erals had imagined things would turn out; their opinion now became divided; 

 the majority of them sided with the new work of unification and its leaders, 

 while a smaller group still insisted upon their demand for liberal-minded 

 social reforms. To this latter group belonged some of the leading scientists 

 in Germany, and among them Haeckel, although, living as he did in the 

 small town of Jena, he never took an active part in politics. It was with 

 all the greater enthusiasm, then, that he devoted himself to promoting this 

 radical development in the sphere of general culture, and he rapidly gained 

 a following of people with similar ideas to his own, who took up the strug- 

 gle against dogmatic conservatism in both the social and the religious sphere, 

 employing the evolution theory of Darwinism as their principal weapon. Of 

 course the authorities viewed with anything but friendly eyes this natural- 

 scientific opposition, with its social tinge; the employment of these hostile 



