1 98 CARNEGIB INSTITUTION 



and the actual results of the application of the experimental 

 method are, we venture to think, greater, relatively speaking, than 

 those of any other science in the corresponding period. Sufficient 

 advance has been made to justify the establishment, in the great 

 universities, of laboratories and other material aids to psychological 

 research. The literature of the subject, as hsted in The Psycholog- 

 ical Index, reaches for 1901 an astonishingly large number of titles, 

 and two great reviews are regularly published in this country alone, 

 one of them also finding it necessary to issue large supplements for 

 the printing of extensive pieces of research. 



Certain more general features of contemporary psychological 

 work, when viewed with reference to such a grouping of the sciences 

 as that suggested above, may be pointed out. In the first place, 

 the development of psychology is necessary for the sound solution 

 of most important problems in the physical and natural sciences. 

 In physics, for example, matters of direct psychological import 

 come up for treatment, such, for example, as the question of the 

 personal equation in astronomy, the question of the normal function 

 of the senses in physical observation, the question of the extent and 

 psychological justification of the various methods of research — all 

 problems in which, as history shows, final solutions have waited 

 upon the results of psychological criticism and research. In the 

 biological sciences the same is true, but to a greater extent. The 

 development of genetic psychology in recent years has been perhaps 

 the most important modifying influence in general biological theories. 

 The problem of evolution is now as much psychological as biolog- 

 ical, and the biologists themselves are prepared to ask the coopera- 

 tion of expert psychologists in their most difficult undertakings. 

 Apart from this relation of psychological investigation to that in 

 the physical and natural sciences, the direct value of psychology in 

 connection with all the sciences of man remains over — a fact which 

 in itself is sufficient justification for the most liberal endowment of 

 psychological research. 



The principal function, as we conceive it, of such a new establish- 

 ment as the Carnegie Institution in relation to psychology should be 

 that of unification — the function which is of the first importance in 

 reference to the relationships of all the sciences. The develop- 

 ment of psychology, rapid as it has been, has been along distinct 

 lines. We have today no less than five general undertakings, all 

 yielding fruitful results and each pursued by more or less inde- 

 pendent methods, namely : ist, Laboratory Psychology (including 



