224 Induction. [CHAP. ix. 



so simple and so obviously applicable as that which, in a 

 former case, recommended us always to prefer the more 

 special statistics, when sufficiently extensive, to those which 

 are wider and more general. We have no means here of 

 knowing whether one set is more special than the other. 



And in this no difficulty can be found, so long as we 

 confine ourselves to a just view of the subject. Let me 

 again recall to the reader s mind what our present position 

 is; we have substituted for knowledge of the individual 

 (finding that unattainable) a knowledge of what occurs in 

 the average of similar cases. This step had to be taken the 

 moment the problem was handed over to Probability. But 

 the conception of similarity in the cases introduces us to a 

 perplexity; we manage indeed to evade it in many in 

 stances, but here it is inevitably forced upon our notice. 

 There are here two aspects of this similarity, and they 

 introduce us to two distinct averages. Two assertions are 

 made as to what happens in the long run, and both of these 

 assertions, by supposition, are verified. Of their truth there 

 need be no doubt, for both were supposed to be obtained 

 from experience. 



24. It may perhaps be supposed that such an example 

 as this is a reductio ad absurdum of the principle upon which 

 Life and other Insurances are founded. But a moment s 

 consideration will show that this is quite a mistake, and 

 that the principle of insurance is just as applicable to 

 examples of this kind as to any other. An office need find 

 no difficulty in the case supposed. They might (for a reason 

 to be mentioned presently, they probably would not) insure 

 the individual without inconsistency at a rate determined 

 by either average. They might say to him, &quot;You are an 

 Englishman. Out of the multitude of English who come to 

 us nine in ten die if they go to Madeira. We will insure 



