PERCEPTION. 125 



CHAPTER IX. 



Perception. 



At the level marked 18 I represent the rise from Sensa- 

 tion to Perception. By this term I mean, in accordance 

 with general usage, the faculty of cognition. " The contrast 

 between Sensation and Perception is the contrast between 

 the sensitive and the cognitive, intellectual, or knowledge- 

 giving functions." (Bain.) " Perception is an establishment 

 of specific relations among states of consciousness ; and this 

 is distinguished from the establishment of these states of 

 consciousness themselves," which constitutes Sensation. 

 (Spencer.) " In Perception the material of Sensation is 

 acted on by the mind, which embodies in its present attitude 

 all the results of its past growth." (Sully.) 



Sensation, then, does not involve any of the powers of 

 the intellect as distinguished from consciousness, but Percep- 

 ti< hi implies the necessary occurrence of an intellectual or 

 cognitive process, even though it be a process of the simplest 

 possible kind. The term Perception, therefore, may be 

 applied to all cases where a process of cognition occurs, 

 whether such process arises directly or indirectly out of sen- 

 Bation ; thus it is equally correct to say that we perceive the 

 colour or the scent of a rose, and that we perceive the truth 

 <>r the probability of a proposition. 



Otherwise phrased we may state the distinction between 

 Sensation aud Perception thus. A sensation is an elementary 

 or undecompo8able state of consciousness, but a perception 

 involves a process of mentally interpreting the sensation in 

 terms of past experience. For instance, there is a closed book 

 lying on the table before me; my eyes have been resting on 

 its cover for a considerable time while I have been thinking 

 how I Bhould arrange the material of the present chapter. 

 All that time I have bei d i eiving a visual sensation of a 



