NATURE OF STATISTICAL KNOWLEDGE 85 



employed in all sorts of cases. This point of 

 view reaches, it seems to me, its limit in the sen- 

 tence already quoted from Royce, which I venture 

 to repeat with one word italicized. "There is, 

 therefore, good reason to say that not the mechan- 

 ical but the statistical form is the canonical 

 form of scientific theory, and that if we knew the 

 natural world millions of times more widely and 

 minutely than we do, the mortality tables and the 

 computations based upon a knowledge of aver- 

 ages, would express our scientific knowledge about 

 individual events, much better than the nautical 

 almanac would do." 



This leads us to consider carefully the general 

 question of the validity on the one hand, and the 

 usefulness on the other hand, of this whole second 

 mode of employment of the statistical method. 

 It is the one which has attracted the greatest 

 attention because of its essentially spectacular 

 nature coupled with a sort of mysteriousness 

 bordering upon the miraculous. It seems a 

 wonderful, indeed almost a superhuman, accom- 

 plishment to be able to say in the manner of the 

 oracles of old, "So many men will commit suicide 

 next year." 



IV 



Since Clerk-Maxwell introduced statistical 

 modes of reasoning into physical science there has 

 been an ever increasing tendency to regard the 



