Mat 13, 1904.] 



SCIENCE. 



755 



thing in nature, the thing which organisms 

 show in all eases, their latest and finest ad- 

 justment and the central fact of conscious- 

 ness, its prime instrument, its selective 

 agent, its seizing, grasping, relating, as- 

 similating, apperceiving— in short, its ac- 

 commodating element and process— is at- 

 tention. ' ' 



Probably in no direction has more solid 

 advance been made within the last ten 

 years than in the psychology of instinct, 

 impulse, habit and kindred subjects. Pro- 

 fessor Lloyd Morgan's best contributions 

 have been in this realm. In this he has 

 been both the observer and the thinker, 

 and his biological training has been at once 

 a preparation for the task and a ground of 

 confidence for the reader of his works. His 

 'Habit and Instinct' embodies much of the 

 best that has been attained in that depart- 

 ment. He, however, wisely draws on the 

 stores of others and in these subjects the 

 data are more abundant and reliable prob- 

 ably than in any other department of the 

 whole field. The investigations of the 

 Peckhams on insects deserve in this con- 

 nection special mention. All agree that it 

 is here that man and the animals stand on 

 common ground. There is scarcely a 

 prominent writer on human psychology 

 who has not treated at greater or less 

 length of the subject of impulse, instinct 

 and habit. However, a great field is yet 

 open, notwithstanding all that has been 

 done, including such bold attempts as that 

 of Professor Baldwin and others, to deter- 

 mine the sphere of these fundamental ac- 

 tivities in the course of organic evolution in 

 general. 



The limitations of this address will not 

 permit of extended reference to this sub- 

 ject, in which some of the best work of the 

 last decade has been done. But at least a 

 word must be said of the investigations of 

 Professor Groos, whose books on the play 

 of animals and play in the human being 



are mines of learning and full of suggest- 

 ive, highly interesting and generally valu- 

 able information. Mr. H. R. Marshall has 

 also quite recently devoted an entire work 

 to the subject of 'Instinct and Reason.' 



It seems to me that development in this 

 subject has been retarded by an inadequate 

 appreciation of what I conceive to be of the 

 greatest moment: that the qualifications 

 of the investigator are of quite as much 

 importance as the method, probably a great 

 deal more. Professor Groos has thus re- 

 ferred to the equipment of the individual 

 who would study animals in one of their 

 aspects: 'The author of the psychology of 

 animal play should have in reality, not 

 alone two but many souls ^vithin his breast. ' 

 He would have him combine with all the 

 varied ideas and experiences of a man who 

 has traversed the round globe, the special 

 Imowledge of the director of a zoological 

 garden, and also that of him who has pene- 

 trated the life secrets of the forest, and 

 who can moreover take the point of view of 

 a student of sestheties. If these are the 

 qualifications for a special investigation of 

 animal play, they are surely not less called 

 for in the other realms of comparative psy- 

 chology. However, many who are not 

 qualified to do the highest kind of work in 

 this department of investigation can, if 

 they will, make contributions of accurate 

 observations ; but they must be slow to draw 

 conclusions and have a saving modesty 

 which can hardly be claimed as the most 

 distinctive characteristic of the present-day 

 investigator, but which so often caused 

 Charles Darwin to pause. 



To more than one has it seemed desirable 

 that some correlation between the animal 

 and the human mind should be attempted, 

 and this could be best done by comparing 

 the former with the human within a rela- 

 tively short time after birth. Already a 

 goodly store of material is available, but 



