HYPOTHESIS 161 



because the former distance by rail is twice the latter. And 

 when we pass out of the domain of purely quantitative relations 

 it becomes difficult to know for certain (a) that the relations are 

 really identical, and (&) that what we infer from the identity de 

 pends on it alone. Our inference is based merely on similarity 

 of relations, and yields only a probable conclusion. This is the 

 sort of inference illustrated by Aristotle s example of the similar 

 relations of sight to body and intellect to soul. . It is a very 

 common form of inference. We may argue, for instance, that 

 because the relation of colony to mother-country is like that 

 of child to parent, the reciprocal rights and duties of the 

 former pair should be the same as those of the latter pair. Or 

 again, the colonies may be compared to the fruit that drops off 

 from the parent-tree when ripe. 1 Obviously, inferences of this 

 kind may be of any degree of value or of worthlessness. It is 

 such resemblances between things that give rise to the metaphori 

 cal use of language (e.g. &quot; mother-country &quot;). Metaphors are 

 simply analogies of this kind compressed into a single word or 

 phrase ; and metaphors are often misleading. 



Between this &quot; Aristotelean &quot; analogy, and analogy in the 

 modern sense, there is no essential difference. In the former the 

 inference is based on similarity of relations, in the latter it is 

 based on similarity of qualities, properties, or characteristics of 

 any sort. The former may be symbolically stated : &quot; a is related 

 to b as c is to d ; from the relation of a to such and such a 

 consequence follows, therefore it follows also from the relation of 

 cto d&quot; ; the latter: &quot;a resembles b in certain respects ;tr ; a ex 

 hibits the character y, therefore b will exhibit the character y 

 also&quot;. 2 Similarity of relations must involve some similarity of 

 inherent attributes or qualities in the things related, and so it 

 was quite natural and inevitable that the term &quot; analogy &quot; should 

 be extended, as it has been, from the former to the latter. 3 



WALTON, Logic, ii., bk. v., chaps, iii. and iv. JOSEPH, Introd. to Logic, 

 chaps, xxi., xxii. and xxiii. ; pp. 492 sqq. MELLONE, op. cit., pp. 251-64, 

 317-40. MILL, Logic, III., v., xx. MERCIER, Logique, pp. 334-49- 



X C/. JOSEPH, op. cit., p. 494. *ibid., p. 496. 3 ibid., p. 498. 



VOL. II. II 



