NATURE OF STATISTICAL KNOWLEDGE 79 



III 



A careful consideration of the history of statis- 

 tical science, as well as of the present day appli- 

 cation of these methods, leads to the conclusion 

 that statistical methods are used for two sorts 

 of purposes, or to gain two sorts of knowledge 

 about events or things. 



A. On the one hand the statistical method 

 finds one of its chief uses in furnishing a method 

 (and the only one known in science) of describing 

 a group in terms of the group's attributes, rather 

 than in terms of the attributes of the individuals 

 which compose the group. This important use of 

 the statistical method is not usually formulated 

 in just the way I have put it here, or in an earlier 

 chapter (p. 54). On that account it may be well 

 to consider the point a little more analytically. 



What sorts of positive, definite, and exact 

 knowledge do statistics give us? 



1. Precise knowledge of the composition of 

 groups or masses. This is the knowledge gained 

 by counting. Suppose we find a basket contain- 

 ing a number of balls of several different colors, 

 and proceed to count them with the following 

 results : 



7 Reds 



9 White 



2 Black 



1 Green 



