398 THE POPULAR SCIENCE MONTHLY 



tively little account of the distinction between feeling more or less per- 

 sonal satisfaction in partial agreements between experience and our ex- 

 pectations, and precisely confirming or refuting a determinate hypoth- 

 esis, in so far as that can be done by a certain group of experiences. 



And finally the student of logic finds a certain difficulty in the 

 usual statements of pragmatism regarding the sense in which empirical 

 verifications are said to lead to a certain " belief " that the ideas which 

 we have been trying to verify are true. In ordinary life beliefs exist 

 in all sorts of vague degrees of intensity. But when the student of a 

 science formulates his results, considerable stress is laid upon the asser- 

 tion that, by virtue of a given group of confirmations, a hypothesis 

 has received a somewhat determinate degree of what is called objective 

 probability. Now into the theory of probability this is no place to go. 

 But most of you who have dealt with statistical probabilities will admit 

 that our subjective confidence is somewhat different in its nature from 

 that objective or statistically estimated probability which most students 

 of an inductive science prefer to be able to define if they can. The 

 whole modern development of the theory of probability has been in 

 the direction of separating the concept of objective probability from 

 the concept of subjective belief or confidence. From the objective point 

 of view a proposition has a certain probability P in case it belongs to 

 the class of propositions of which in the long run a proportion P are 

 true. The difficulty of defining such probability with genuine exact- 

 ness is great, and the whole subject of probability is too complex to 

 be here discussed, but the student of logic feels dissatisfied with the 

 fact that his pragmatist brethren take little interest in defining the 

 difference between the vague confidence which in the world of common 

 sense confirmed expectations may arouse, and the scientific measure of 

 probability in exact and relatively objective terms which the students 

 of an inductive science are commonly seeking. 



II 



So much for my general statement of logical scruples concerning 

 the adequacy of pragmatistic formulations. Into the merits of these 

 logical scruples I have no wish to go on this occasion. I have stated 

 them merely in order to formulate the problems of a psychological nature 

 to which I wish to attract attention. Pragmatism has emphasized these 

 problems, has undertaken to solve them, has contributed a great deal 

 to their study, but in my opinion has failed to satisfy all the require- 

 ments that it might satisfy, just because it is not sufficiently interested 

 in the very logical problems that I have just outlined. These logical 

 problems, however, have their psychological aspects. If one does not 

 deal with them in an exact fashion from the logical point of view, one 

 is not likely to have one's attention attracted to their psychological 



