504 SCIENTIFIC THOUGHT. 



be an unrealisable ideal in that it dealt with inner 

 phenomena as unconnected with outer ones : a psycho- 

 physical mechanism was a nearer approach to a true 

 description of reality, and could not he narrowed down 

 to a purely physical occurrence ; moreover, the unity 

 of mental life was a special property which had to 

 be recognised and denned. 

 26. Lotze himself, after formulating the conception of a 



The psycho- 

 physics of psycho-physical mechanism, and utilising the elaborate 



vision. L J r J 



and fundamental experiments and observations of Weber 

 as illustrations of what was meant, made an important 

 contribution towards an analysis of a compound physico- 

 psychical process. He took up the problem which 

 Berkeley had attacked, of the formation of our space 

 perception. It had been introduced into German 

 psychology mainly through Herbart with reference to 

 the Kantian doctrine that space is a subjective form. 

 Through Lotze, and subsequently through Helmholtz, it 

 has been shown to have not only a psychological but 

 likewise a physiological importance : it is a problem of 

 psycho-physics. 



There exists a peculiar difficulty in bringing home to 

 the popular mind the fact that a special problem is in- 



may be noted. First, it is clear 

 that Lotze was an " organicist " 

 before Claude Bernard and other 

 more recent thinkers mentioned 

 above. Secondly, it is very evident 

 that Lotze belongs to the pre- 

 Darwinian school of thought. In 

 fact, he does not relish the genetic 

 aspect. The historical beginnings 

 of ideas are for him no indication of 

 their value and correctness. He 

 says on this point : "The genesis of 

 a conception is no argument for its 



validity ; in the ever indistinct 

 manner in which language operates 

 in forming its words, it may form 

 the correctest conceptions in just 

 as incorrect a manner as the most 

 erroneous ones. What is important 

 is whether the conception, formed 

 anyhow, can justify itself " (' Med. 

 Psychol.,' p. 41). I shall on 

 another occasion have to refer 

 more fully to this marked absence 

 of the historical sense in Lotze. 



