84 HUME II 



process of association ; that is to say, is a result 

 of the process of which it is supposed to be the 

 cause. Moreover, since, as Hume is never weary 

 of reminding his readers, there is nothing in ideas 

 save copies of impressions, the qualities of re- 

 semblance, contiguity, and so on, in the idea, must 

 have existed in the impression of which that idea 

 is a copy ; and therefore they must be either 

 sensations or emotions from both of which 

 classes they are excluded. 



In fact, in one place, Hume himself has an 

 insight into the real nature of relations. Speaking 

 of equality, in the sense of a relation of quantity, 

 he says 



" Since equality is a relation, it is not, strictly speaking, a 

 property in the figures themselves, but arises merely from the 

 comparison which the mind makes between them." (I. p. 

 70.) 



That is to say, when two impressions of equal 

 figures are present, there arises in the mind a 

 tertium quid, which is the perception of equality. 

 On his own principles, Hume should therefore 

 have placed this " perception " among the ideas of 

 reflection. However, as we have seen, he ex- 

 pressly excludes everything but the emotions and 

 the passions from this group. 



It is necessary therefore to amend Hume's 

 primary " geography of the mind " by the exci- 

 sion of one territory and the addition of another ; 



