206 SCIENTIFIC METHOD IN PHILOSOPHY 



are any the worse for the doctrine that classes are fictions. 

 What the doctrine is, and why it is not destructive, I will 

 try briefly to explain. 



On account of certain rather complicated difficulties, 

 culminating in definite contradictions, I was led to the 

 view that nothing that can be said significantly about 

 things, i.e. particulars, can be said significantly {i.e. either 

 truly or falsely) about classes of things. That is to say, 

 if, in any sentence in which a thing is mentioned, you 

 substitute a class for the thing, you no longer have a 

 sentence that has any meaning : the sentence is no longer 

 either true or false, but a meaningless collection of words. 

 Appearances to the contrary can be dispelled by a 

 moment's reflection. For example, in the sentence, 

 " Adam is fond of apples," you may substitute mankind, 

 and say, " Mankind is fond of apples." But obviously 

 you do not mean that there is one individual, called 

 " mankind," which munches apples : you mean that the 

 separate individuals who compose mankind are each 

 severally fond of apples. 



Now, if nothing that can be said significantly about a 

 thing can be said significantly about a class of things, it 

 follows that classes of things cannot have the same kind 

 of reality as things have ; for if they had, a class could 

 be substituted for a thing in a proposition predicating 

 the kind of reality which would be common to both. 

 This view is really consonant to common sense. In the 

 third or fourth century b.c. there lived a Chinese philo- 

 sopher named Hui Tzu, who maintained that " a bay 

 horse and a dun cow are three ; because taken separately 

 they are two, and taken together they are one : two and 

 one make three." l The author from whom I quote says 

 that Hui Tzti " was particularly fond of the quibbles 



1 Giles, The Civilisation of China (Home University Library), p. 147. 



