THE PRESENT STATE OF THE QUESTION REGARDING 

 THE FIRST PRINCIPLES OF THEORETICAL 



SCIENCE. 



By JOSIAH ROYCE. 

 (Read April ig, 1906.) 



I venture to use this opportunity to call attention to the existence 

 and to the spirit of certain researches in which a good many well- 

 equipped students of science are now taking part, and in which I 

 myself, although very ill prepared for the work, have already tried 

 in a very modest way to take some part myself. These researches 

 interest primarily logicians, and to some extent mathematicians. 

 They have a relation, however, not only to general philosophy, but 

 also to the interests of a good many students of the special sciences. 

 Let me try briefly to indicate the problems which give rise to such 

 researches. 



I. 



Science, as we all know, has two aspects, namely, that aspect 

 which is concerned with discovering and reporting facts, and that 

 aspect which is concerned in constructing and applying theories. A 

 scientific theory is a body of assertions connected together by proc- 

 esses of logical reasoning, and so chosen as to be of use in display- 

 ing the rational connections of facts, and in predicting facts which 

 have not yet been observed. The extent to which theories are of 

 use for the work of a given science varies very greatly with the 

 stage of evolution which the science has reached, with the character 

 of the subject matter and with the interests which control our study 

 of the facts in question. Celestial mechanics furnishes an instance 

 of a very highly developed theoretical branch of science. The ex- 

 tent to which theory is significant and successful in any one science, 

 as for instance in biology or in chemistry, is in case of each such 

 branch of scientific inquiry a kind of test of the stage which the 

 science in question has reached in its evolution. In the history of 



82 



