396 Testimony. [CHAP. xvi. 



Each of these circumstances would serve to specialize the 

 individual, and therefore to restrict the limits of the statistics 

 which were applicable to his case. But the consideration of 

 such qualities as these would either leave the average pre 

 cisely as it was, or produce such an unimportant alteration 

 in it as no one would think of taking into account. Though 

 we could hardly say with certainty of any conceivable 

 characteristic that it has absolutely no bearing on the 

 result, we may still feel very confident that the bearing of 

 such characteristics as these is utterly insignificant. Of 

 course in the extreme case of the things most perfectly 

 suited to the Calculus of Probability, viz. games of pure 

 chance, these subsidiary characteristics are quite irrelevant. 

 Any further particulars about the characteristics of the cards 

 in a really fair pack, beyond those which are familiar to all 

 the players, would convey no information whatever about the 

 result. 



Or again; although the different sets of statistics may 

 not as above give almost identical results, yet they may do 

 what practically comes to very much the same thing, that 

 is, arrange themselves into a small number of groups, all of 

 the statistics in any one group practically coinciding in their 

 results. If for example a consumptive man desired to insure 

 his life, there would be a marked difference in the statistics 

 according as we took his peculiar state of health into account 

 or not. We should here have two sets of statistics, so clearly 

 marked off from one another that they might almost rank 

 with the distinctions of natural kinds, and which would in 

 consequence offer decidedly different results. If we were 

 to specialize still further, by taking into account insignificant 

 qualities like those mentioned in the last paragraph, we 

 might indeed get more limited sets of statistics applicable 

 to persons still more closely resembling the individual in 



