ii.] TERMS. 20 



is a term capable of plurality ; for there may be a great 

 many pieces discriminated either by their various shapes 

 and sizes, or, in the absence of such marks, by simul- 

 taneously occupying different parts of space. In substance 

 they are one ; as regards the properties of space they are 

 many. 1 We need not further pursue this question, which 

 involves the distinction between unity and plurality, until 

 we consider the principles of number in a subsequent 

 chapter. 



Collective Terms. 



We must clearly distinguish between the collective and 

 the general meanings of terms. The same name may be 

 used to denote the whole body of existing objects of a 

 certain kind, or any one of those objects taken separately. 

 " Man " may mean the aggregate of existing men, which we 

 sometimes describe as mankind; it is also the general 

 name applying to any man. The vegetable kingdom is 

 the name of the whole aggregate of plants, but " plant " 

 itself is a general name applying to any one or other plant. 

 Every material object may be conceived as divisible into 

 parts, and is therefore collective as regards those parts. 

 The animal body is made up of cells and fibres, a crystal 

 of molecules ; wherever physical division, or as it has been 

 called partition, is possible, there we deal in reality with a 

 collective whole. Thus the greater number of general 

 terms are at the same time collective as regards each 

 individual whole which they denote. 



It need hardly be pointed out that we must not infer of 

 a collective whole what we know only of the parts, nor of 

 the parts what we know only of the whole. The relation 

 of whole and part is not one of identity, and does not 

 allow of substitution. There may nevertheless be qualities 

 which are true alike of the whole and of its parts. A 

 number of organ-pipes tuned in unison produce an aggre- 

 gate of sound which is of exactly the same pitch as each 



1 Professor Robertson has criticised my introduction of " Substantial 

 Terms" (Mind, vol. i.p. 210), and objects, perhaps correctly, that the 

 distinction if valid is extra-logical. I am inclined to think, however, 

 that the doctrine of terms is, strictly speaking, for the most part 

 extra-logical. 



