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of racial evolution, they are still fellow-workers, for in the case of 

 physical anthropology of human races at least the methods are the same 

 which are employed in zoology generally. Of course it would be absurd 

 for any one to contend that all the problems of anthropology are strictly 

 zoological questions; to qualify here an investigator must be familiar 

 with linguistics, racial customs and beliefs, and many subjects that 

 are as such apparently outside the limits of zoology. But unless a 

 sharp line is to be drawn between the slow origin by evolution of the 

 human species and the later history of this species, the comparative and 

 genetic methods of analysis which render the earlier process intelligible 

 can scarcely fail to be of service in dealing with the latter. The great 

 danger, which the zoologist himself clearly sees, arises from a tendency 

 to ignore the detail in formulating the general, to oversimplify the 

 problems of the more recent history. For human conscious elements 

 are so complex and plastic that the problems of racial evolution are 

 rendered far more intricate than the broad zoological analysis of the 

 origin of man as a species. 



Psychology, in the second place, is a subject that is related to 

 zoology by the closest of ties, the bond of union being again the common 

 human element. To be sure, the zoologist finds enough in his own 

 field to occupy him fully, but the compaative study of nervous systems, 

 and of the reflex, instinctive, intelligent and reasoned responses of 

 animals brings him inevitably to consider the relation of human men- 

 tality and consciousness to the other terms of the animal series. Deal- 

 ing strictly as a zoologist with animals and their lives, the investigator 

 learns that the machine-like regularity of reflex and instinctive activ- 

 ities is correlated, broadly speaking, with simple nervous organization; 

 that the plasticity of intelligent response is not gained until the physical 

 basis becomes far more complicated; and finally that reason and con- 

 sciousness are in some way bound up with the higher development of 

 the nerve-centers or ganglia that make up the brain. So the zoologist 

 is inclined to believe that the comparative series of mental grades 

 which culminates in the consciousness, or rather the self-consciousness, 

 of the adult human organism, and the series of developmental stages 

 through which the human mental structure passes during infancy and 

 childhood, indicate an evolution in time of the psychic being of man. 

 Whatever may be the outcome of further study, Eomanes, Lloyd 

 Morgan, Forel and Thorndike, among those of modern times, have 

 demonstrated that the genetic methods of zoology are useful instru- 

 ments for the psychologist, who, I believe, is becoming more and more 

 a student of zoological materials as he realizes the advantage of study- 

 ing the simpler psychic phenomena of animals lower than man. 



In venturing to speak of the relation of zoology to sociology and 

 ethics, I am well aware that I shall be charged with straying beyond 



