396 THE POPULAR SCIENCE MONTHLY 



because I do not wholly accept the pragmatist theory of truth. I recog- 

 nize the connection in my ovm mind between the two dissatisfactions. 

 I do not wish to pretend that I can wholly dissociate my interest in 

 psychology from my interest in the other aspects of the pragmatist con- 

 troversy and in the very nature of pragmatism itself. My pragmatist 

 friends least of all would desire me to do this. And so I shall aid you 

 in following my further inquiries if I first briefly state one ground of 

 my dissatisfaction as a student of logic and of general philosophy, with 

 the pragamtist's theory of truth. This statement I make not as if it 

 were here important for the psychological purpose of this discussion, 

 but because by confessing my own state of mind I may help you to fix 

 your attention upon matters that will more directly interest you. For 

 my dissatisfaction as a student of logic, with the pragmatist theory 

 regarding truth, will call attention to the way in which I should 

 approach precisely those psychological problems which pragmatism has 

 most emphasized. 



I 



When pragmatism asserts that the truth of a proposition is tested 

 by the " workings " of the ideas that the proposition expresses, a student 

 of logic very naturally raises the question as to what workings are 

 meant. A man who hears a proposition and who more or less com- 

 pletely understands its meaning, and who hereupon more or less believes 

 the proposition, has certain mental attitudes aroused in him, and these 

 mental attitudes have their physical expression. They tend to lead to 

 action. The action may well be accompained by expectations of various 

 sorts, and the expectations may remain throughout more or less identical 

 with those that the utterance of the proposition first arouses in the mind 

 of the inquirer. Thus ideas may lead to actions. These actions may 

 gratify or in a measure satisfy expectations. In this case the ideas 

 which the proposition expressed are said to " work." But now consider 

 the contrast between what this decidedly general statement expresses 

 and what a student of any more exact empirical science is likely to 

 have in mind when he thinks of testing the truth of a definite asser- 

 tion. One familiar process of testing the truth of hypotheses in scien- 

 tific regions is to trace the consequences that must be true if those 

 hypotheses are true, and then to see whether these consequences can be 

 found verified by particular experiences. An essential part of this 

 process is the deduction of certain consequences from one's hypothesis. 

 How extensive this deductive process may be, a glance at any text- 

 book of theoretical physics, in particular of theoretical astronomy of 

 the classic type, will show. 



Now what happens when one deduces the consequences of an h^itothe- 

 sis? Does one simply let one's ideas work? Are the consequences of 

 hypotheses simply ideas that are as a fact aroused in the mind of a 



