ABSTRACTION. 46i 



CHAPTER II. 



OP ABSTRACTION, OR THE FORMATION OF CONCEPTIONS. 



§ 1. The metaphysical inquiry into the nature and composition of ■what 

 have been called Abstract Ideas, or, in other words, of the notions which 

 answer in the mind to classes and to general names, belongs not to Logic, 

 but to a different science, and our purpose does not require that we should 

 enter upon it here. We are only concerned with the universally acknowl- 

 edged fact, that such notions or conceptions do exist. The mind can con- 

 ceive a multitude of individual things as one assemblage or class; and gen- 

 eral names do really suggest to us certain ideas or mental representations, 

 otherwise we could not use the names with consciousness of a meaning. 

 Whether the idea called up by a general name is composed of the various 

 circumstances in which all the individuals denoted by the name agree, and 

 of no others (which is the doctrine of Locke, Brown, and the Conceptual- 

 ists) ; or whether it be the idea of some one of those individuals, clothed in 

 its individualizing peculiarities, 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 

 Mr. James Mill) the idea of the class is that of a miscellaneous 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 conception 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. Whenever we think or reason concerning the class, we do so by 

 means of this idea. And the voluntary power which the mind has, of at- 

 tending to one part of what is present to it at any moment, and neglecting 

 another part, enables us to keep our reasonings and conclusions respecting 

 the class unaffected by any thing in the idea or mental image which is not 

 really, or at least which we do not really believe to be common, to the 

 whole class.f 



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 phe- 

 nomena into a class, that is, when we compare them with one another to 

 ascertain in what they agree, some general conception is implied in this 



* Mr. Bailey has given the best statement of this theory. "The general name," he 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 conscious." (Letters on the Philosophy of the Human Mind, 1st series, letter 22.) But 

 Mr. Bailey must allow that we carry on inductions and ratiocinations respecting the class, by 

 means of this idea or conception 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 member of it. 



1 1 have entered rather fully into this question in chap. xvii. of An Examination of Sir 

 William Hamilton's Philosophy, headed "The Doctrine of Concepts or General Notions," 

 which contains my last views on the subject- 



