ABSTRACTION. 



425 



the individuals denoted by the name 

 agree, and of no others, (which is the 

 doctrine of Locke, Brown, and the 

 C5onceptualist8 ;) or whether it be the 

 idea of some one of those individuals, 

 clothed in its individualising pecu- 

 liarities, but with the accompanying 

 knowledge that those peculiarities are 

 not properties of the class, (which is 

 the doctrine of Berkeley, Mr. Bailey,* 

 and the modern Nominalists ;) or 

 whether (as held by Mi\ James Mill) 

 the idea of the class is that of a mis- 

 cellaneous assemblage of individuals 

 belonging to the class ; or whether, 

 finally, it be any one or any other of 

 all these, according to the accidental 

 circumstances of the case ; certain it 

 is, that some idea or mental concep- 

 tion is suggested by a general name, 

 whenever we either hear it or employ 

 it with consciousness of a meaning. 

 And this, which we may call if we 

 please a general idea, represents in our 

 minds the whole class of things to 

 which the name is applied. When- 

 ever we think or reason concerning 

 the class, we do so by means of this 

 idea. And the voluntary power which 

 the mind has of attending to one 

 part of what is present to it at any 

 moment, and neglecting another part, 

 enables us to keep our reasonings 

 and conclusions ref<pecting the class 

 unaffected by anything in the idea 

 or mental image which is not really, 

 or at least which we do not really 



"* Mr. Bailey has given the best statement 

 of this theory. "The general name," ho 

 says, " raises up the image sometimes of 

 one individual of the class formerly seen, 

 sometimes of another, not unfrequently of 

 many individuals in succession ; and it 

 sometimes suggests an image made up of 

 elements from several different objects, by 

 a latent process of which I am not con- 

 scious " (Letters on the Philosophy of the 

 Human Mind, ist Series, Letter 22). But 

 Mr. Bailey must allow that we carry on 

 inductions and ratiocinatioTis respecting 

 the class by means of this idea or concep- 

 tion of some one individual in it. This is 

 all I require. The name of a class calls up 

 some idea through which we can, to all 

 intents and purposes, think of the class as 

 such, and not solely of an individual mem- 

 ber of it. 



believe to be, common to the whole 

 class.* 



There are, then, such things as 

 general conceptions, or conceptions 

 by means of which we can think 

 generally ; and when we form a set 

 of phenomena into a class, that is, 

 when we compare them with one 

 another to ascertain in what they 

 agree, some general conception is im- 

 plied in this ment.al operation. And 

 inasmuch as such a comparison is a 

 necessary preliminary to Induction, 

 it is most true that Induction could 

 not go on without general concep- 

 tions. 



§ 2. But it does not therefore fol- 

 low that these general conceptions 

 must have existed in the mind pre- 

 viously to the comparison. It is not 

 a law of our intellect, that, in com- 

 paring things with each other and 

 taking note of their agreement, we 

 merely recognise as realised in the 

 outward world something that we 

 already had in our minds. , The con- 

 ception originally found its way to us 

 as the result of such a compari-son. 

 It was obtained (in metaphysical 

 phrase) by abstraction from individual 

 things. These things may be things 

 which we perceived or thought of on 

 former occasions, but they may also 

 be the things which we are perceiving 

 or thinking of on the very occasion. 

 When Kepler compared the observed 

 places of the planet Mars, and found 

 that they agreed in being points of an 

 elliptic circumference, he applied a 

 general conception which was already 

 in his mind, having been derived 

 from his former experience. But this 

 is by no means universally the case. 

 When we compare several objects 

 and find them to agree in being 

 white, or when we compare the 

 various species of ruminating animals 



* I bare entered rather fully into this 

 question in chap, xvii, of An Exoniinu- 

 tion of Sir William Hamilton's Philosophi/, 

 headed " The Doctrine of Concepts or 

 General Notions, " which contains my last 

 views on the subject. 



