78 NAMES AND PROPOSITIONS. 



cases of resemblance. As, for example, equality ; which is 

 but another word for the exact resemblance commonly called 

 identity, considered as subsisting between things in respect of 

 their quantity. And this example forms a suitable transition 

 to the third and last of the three heads under which, as already 

 remarked, Attributes are commonly arranged. 



V. QUANTITY. 



12. Let us imagine two things, between which there 

 is no difference (that is, no dissimilarity), except in quantity 

 alone : for instance, a gallon of water, and more than a 

 gallon of water. A gallon of water, like any other external 

 object, makes its presence known to us by a set of sensations 

 which it excites. Ten gallons of water are also an external 

 object, making its presence known to us in a similar manner; 

 and as we do not mistake ten gallons of water for a gallon 

 of water, it is plain that the set of sensations is more or less 

 different in the two cases. In like manner, a gallon of water, 

 and a gallon of wine, are two external objects, making their 

 presence known by two sets of sensations, which sensations 

 are different from each other. In the first case, however, we 

 say that the difference is in quantity ; in the last there is a 

 difference in quality, while the quantity of the water and of 

 the wine is the same. What is the real distinction between 

 the two cases ? It is not the province of Logic to analyse 

 it ; nor to decide whether it is susceptible of analysis or not. 

 For us the following considerations are sufficient. It is 

 evident that the sensations I receive from the gallon of 

 water, and those I receive from the gallon of wine, are not 

 the same, that is, not precisely alike ; neither are they alto 

 gether unlike: they are partly similar, partly dissimilar; 

 and that in which they resemble is precisely that in which 

 alone the gallon of water and the ten gallons do not resemble. 

 That in which the gallon of water and the gallon of wine are 

 like each other, and in which the gallon and the ten gallons 

 of water are unlike each other, is called their quantity. This 



