LIMITS OF COMPARATIVE PSYCHOLOGY 713 



of a genetic science is anything in its development: whether it study 

 life or consciousness, animal or child or adult, a genetic science studies 

 this object as developing. 



Logically antecedent to all special problems of genetic and of 

 comparative psychology is the question of the scope, and, con- 

 versely, of the limits of each. These problems constitute the 

 main subject of this paper. The first to be considered is: 



I. The Limits of Genetic Psychology 



At the very outset, genetic psychology is met by the challenge 

 to its logical existence. The question is seriously raised whether 

 there is any sense in which consciousness may be said to develop, 

 whether, in other words, there is room for any genetic science 

 of consciousness. It is evident, at once, that consciousness, con- 

 ceived after the atomistic, Humian fashion, as a succession of phe- 

 nomena or events, a chain of ideas, in the widest sense of that 

 word "idea," cannot be said to develop. Development presup- 

 poses a unit of change, that is, some one reality which expands or 

 narrows, grows or decays, and yet retains, throughout its change, 

 a certain identity. The Humian, "linked-idea," conception of con- 

 sciousness has, as its only unit of reality, the single idea, that is, 

 state of consciousness; and the idea does not develop, since it ex- 

 ists for the moment only. 1 Thus, the Humian conception, since 

 it recognizes no reality which underlies that of these evanescent 

 states of consciousness, leaves no room to conceive of conscious- 

 ness as developing. Consistent advocates of this system 2 rightly, 

 therefore, reject the conception of a strictly genetic psychology. 

 They concern themselves, it is true, with genetic biology, in the 

 effort to explain concrete psychic phenomena, explaining, for ex- 

 ample, the fear of empty spaces by the fact that empty spaces 

 were dangerous to our animal ancestors, and that therefore those 

 of them who escaped, through instinctive flight, survived to pro- 

 pagate offspring. This, however, is no genetic psychology; it is 

 a psychological use of the facts of genetic biology. Psychology, as 

 study of succeeding states or processes of consciousness, is not, 

 and may not become, a genetic science. 



A genetic psychology is possible, in truth, only on a radically 

 different view of the nature of consciousness. According to this 

 second doctrine, consciousness is not a mere succession of ideas: it 

 is a self conscious of itself, of other selves, and of its own ideas. The 

 unit of psychology is, from this standpoint, not the single state of 

 consciousness, the idea, but the conscious self. This is not the time 



1 Treatise on Human Nature, bk. i, part iv, sec. 6. 

 3 Cf. Miinsterberg, Grundzuge, chapter xiii. 



