AND CELLULAR PSYCHOLOGY. 51 



the conservation of force, has, therefore, no application 

 in the region of soul-life, and that mechanical causality 

 which prevails throughout all the processes of nature 

 does not exist for the soul. The Psyche, in a word, 

 is a supernatural phenomenon, and the supernatural 

 department of the spiritual world stands free and 

 independent of the natural department of the material 

 world. 



If we now compare the psychological views of the 

 youthful and unprejudiced Virchow of Wiirzhurg with 

 those of the older and mystical Virchow of Berlin, 

 there can be no doubt in the minds of the impartial 

 that the former, a quarter of a century ago, was as 

 decided and logical a monist as the latter is at present 

 a confessed and convicted dualist. The distinguished 

 position which Virchow, twenty- five years since, won 

 by his natural conception of the nature of man, and the 

 great fame which he then earned in the fight for the 

 truth, rest precisely on this, that on every occasion he 

 maintained with his utmost vigour the unity of all vital 

 phenomena, and asserted their mechanical character. 

 All organic life, even the soul-life, rests on mechanical 

 principles, on that causal mechanism of which Kant 

 said that "it alone contained a practical interpreta- 

 tion of nature," and that " without it no natural science 

 can exist." On this point Virchow says well in his 

 discourse on " Efforts at Unity in Scientific Medicine," 



