DISCUSSION 163 



Sensation, sense-perception, and imagination 

 do not by any means account for the whole of our 

 psychical life on its perceptive side. General 

 concepts, judgments, and inferences are far 

 higher components of our knowledge, and psy- 

 chical association does not afford a satisfactory 

 explanation of them, far less does association in 

 the physiological sense, which depends anatom- 

 ically upon the so-called associative fibres. 

 Our concepts, judgments, and inferences are, 

 of course, built up upon a foundation of sense- 

 perception, but in a way differing altogether 

 from that in which the sense-images are formed, 

 for sense-perception is a real element in these. 

 The old saying, Nihil est in intellectu, quod non 

 antea fuerit in sensu, is true only hi as far as 

 sense-perception is a preliminary condition to 

 true intellectual activity, and constitutes the 

 material from which it is formed. The associa- 

 tive theory, properly understood, and kept 

 within its true limits, is therefore absolutely 

 compatible with our assuming the existence 

 of a simple soul ; in fact, it even leads inevit- 

 ably to this assumption. 



3. ' Experiments upon animals and observations 

 of human beings have successfully shown that a 

 great part of our psychical activity must be referred 

 to a particular region of the cerebral cortex. I may 

 remind you that our visual perceptions are con- 



