CHAPTER XXVIII. 



ANALOGY. 



As we have seen in the previous chapter, generalisation 

 passes insensibly into reasoning by analogy, and the difie- 

 rence is one of degi"ee. We are said to generalise when we 

 view many objects as agreeing in a few properties, so that 

 the resemblance is extensive rather than deep. AMien we 

 have only a few objects of thought, but are able to discover 

 many points of resemblance, we argue by analogy that the 

 correspondence will be even deeper than appears. It 

 may not be true that the words are always used in such 

 distinct senses, and there is great vagueness in the employ- 

 ment of these and many logical terms ; but if any clear 

 discrimination can be drawn between generalisation and 

 analogy, it is as indicated above. 



It lias been said, indeed, that analogy denotes not a 

 resemblance between things, but between the relations of 

 things. A pilot is a very different man from a prime 

 minister, but he bears the same relation to a ship that the 

 minister does to the state, so that we may analogically 

 describe the prime minister as the pilot of the state. A 

 man differs still more from a horse, nevertheless four men 

 bear to three men tlie same relation as four horses bear to 

 three horses. There is a real analogy between the tones of 

 tlie Mouochord, the Sages of Greece, and the Gates of 

 Thebes, but it does not extend beyond the fact that they 

 were all seven in number. Between the most discrete 

 notions, as, for instance, those of time and space, analogy 

 may exi.st, ari.sing from the fact that the mathematical 

 conditions of the lapse of time and of motion along a line 



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