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 be narrowed down 

 to a purely physical occurrence; moreover, the unity 

 of mental life was a special property which had to 

 be recognised and defined. 

 26. Lotze himself, after formulating the conception of a 



The psycho- . - , , ... . 



physics of psycho-physical mechanism, and utilising the elaborate 



vision. 



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 in the ever indistinct manner in 



that Lotze was an " organicist" be- which language operates in forming 



fore Claude Bernard and other more its words, it may form the correctest 



recent thinkers mentioned above. conceptions in just as incorrect a 



Secondly, it is very evident that manner as the most erroneous ones. 



Lotze belongs to the pre- Darwinian What is important is whether the 



school of thought. In fact, he does conception, formed anyhow, can 



not relish the genetic aspect. The justify itself "( 'Med. Psychol.,' p. 



historical beginnings of ideas are 41). I shall on another occasion 



for him no indication of their value have to refer more fully to this 



and correctness. He says on this marked absence of the historical 



point : " The genesis of a concep- sense in Lotze. 

 tion is no argument for its validity ; 



