198 



SCIENCE. 



[N. S. Vol. XVIII. No. 450. 



the psychological field. Each psychologist 

 probably has his own pet or changing 

 scheme for dividing, the great typical de- 

 partments of the science as they may ap- 

 peal to him. I have sought to avoid, in 

 the first instance, such a limitation by fol- 

 lowing the revised rubrics of ' The Psycho- 

 logical Index,' introduced in 1900, which 

 may be regarded as the latest and perhaps 

 the best existing scheme of division cover- 

 ing that part of the field of psychology 

 which reaches the stage of print. It 

 groups psychological literature under ten 

 chief heads, which are so divided and sub- 

 divided as to provide a list of eighty-eight 

 different topics. The following classifica- 



statistical unit emploj'ed in gathering the 

 summary. Such a mode of classification 

 must be based on the equivocal unit derived 

 by making each paper, report or address 

 in a set discussion stand as an integer, be- 

 coming the unitary equivalent of every 

 other paper, report or discussion. The 

 amount of psychological material, the ex- 

 penditure of labor required in its prepara- 

 tion, and the comparative and the net 

 values of its results, either as research or 

 as criticism, represented in this arbitrary 

 unit are completely lost sight of in such 

 a scheme. This is unavoidable. What the 

 table truly represents is the number of 

 times the given psychological topics have 



tion of the material available is therefore 

 based on those rubrics. The table includes 

 the presidential addresses and papers pre- 

 sented by title only, but omits the material 

 presented by six persons at the preliminary 

 meeting in 1892 and the general discussions 

 which may have followed any papers. 



In preparing such a classification of an 

 enormously varied material, it must be 

 readily confessed that extreme diificulty 

 was often met in deciding the topical prop- 

 erties of a given communication or report. 

 In making the statistical distribution, I 

 have had a special care to represent the 

 themes as faithfully as possible. Special 

 comment must also be made concerning the 



been more or less within the focus of the 

 association's attention, and the distribution 

 of these topics throughout the whole field 

 of psychological investigation. 



Accepting this mode of bunching the 

 work of the ten years, our table offers the 

 following summary. The annual meetings 

 have called forth fifty-six papers on gen- 

 eral topics, seven on the nervous system, 

 fifty-three on sensation, thirteen on the 

 characters of consciousness, thirty-four on 

 cognition, two on affection (pleasure and 

 pain being grouped under sensation), sev- 

 enteen on conation and movement, thirty- 

 nine on the higher manifestations of mind, 

 ten on sleep, trance and pathology, forty- 



