PSYCHOLOGY. 



CHAPTER XVII. 



SENSATION. 



After inner perception, outer perception ! The next 

 three chapters will treat of the processes by which we cog- 

 nize at all times the present world of space and the mate- 

 rial things which it contains. And first, of the process 

 called Sensation. 



SENSATIOIJ^ AND PERCEPTION" DISTINGUISHED. 



The words Sensation and Perception do not carry very 

 definitely discriminated meanings in popular speech, and in 

 Psychology also their meanings run into each other. Both 

 of them name processes in which we cognize an objective 

 world; both (under normal conditions) need the stimula- 

 tion of incoming nerves ere they can occur ; Perception 

 always involves Sensation as a portion of itself ; and Sensa- 

 tion in turn never takes place in adult life without Percep- 

 tion also being there. They are therefore names for dif- 

 ferent cognitive functions, not for different sorts of mental 

 fact. The nearer the object cognized comes to being a 

 simple quality like 'hot,' 'cold,' 'red,' 'noise,' 'pain,' ap- 

 prehended irrelatively to other things, the more the state 

 of mind approaches pure sensation. The fuller of relations 

 the object is, on the contrary ; the more it is something 

 classed, located, measured, compared, assigned to a func- 

 tion, etc., etc.; the more unreservedly do we call the state 

 of mind a perception, and the relatively smaller is the part 

 in it which sensation plays. 



Sensation, then, so long as ive take the analytic point of 



