xii.] THE METAPHYSICS OF SENSATION. 311 



me that he has fallen into a great error, and one which 

 is the chief source of his paradoxes about geometry. 



Berkeley in fact employs the word &quot; idea &quot; in this 

 instance to denote two totally different classes of feelings, 

 or states of consciousness. For these may be divided 

 into two groups : the primary feelings, which exist in 

 themselves and without relation to any other, such as 

 pleasure and pain, desire, and the simple sensations ob 

 tained through the sensory organs ; and the secondary 

 feelings, which express those relations of primary feelings 

 which are perceived by the mind ; and the existence of 

 which, therefore, implies the pre-existence of at least two 

 of the primary feelings. Such are likeness and unlike- 

 ness in quality, quantity, or form ; succession and con 

 temporaneity ; contiguity and distance ; cause and effect ; 

 motion and rest. 



Now it is quite true that there is no likeness between 

 the primary feelings which are grouped under sight and 

 touch ; but it appears to me wholly untrue, and indeed 

 absurd, to affirm that there is no likeness between the 

 secondary feelings which express the relations of the 

 primary ones. 



The relation of succession perceived between the visible 

 taps of a hammer, is, to my mind, exactly like the 

 relation of succession between the tangible taps ; the un- 

 likeness between red and blue is a mental phenomenon 

 of the same order as the unlikeness between rough and 

 smooth. Two points visibly distant are so, because one 

 or more units of visible length (minima msibilict) are 

 interposed between them ; and as two points tangibly 

 distant are so, because one or more units of tangible 

 length (minima tangibilia) are interposed between them, 

 it is clear that the &amp;lt; notion of interposition of units of 

 sensibility, or minima sensibilia, is an idea common to 

 the two. And whether I see a point move across the 



