DEVELOPMENT AND CREATION. 9 



is as thoroughly penetrated by the truth of his 

 principles as I, as a Monist, am of mine. This 

 is undoubtedly the upshot of his Munich address, 

 though he is throughout careful to avoid acknow- 

 ledging his chief standpoint in all its nakedness. 

 On the contrary, even now he still veils his anta- 

 gonism under the phrase, which is also a favourite 

 with the clerical papers, that the theory of descent is 

 an " unproved hypothesis." Now it is clear that this 

 theory never will be "proved" if the proofs that 

 already lie before us are not sufficient. ; How often 

 has it been repeated that the scientific certainty of the 

 hypothesis of descent is not grounded in this or that 

 isolated experiment, but in the collective sum of 

 biological phenomena; in the causal nexus of evolu- 

 tion. Then what are the new proofs of the theory of 

 descent which Virchow demands of us ? 



