1 8 The Animal Mind 



this position from widely different philosophical points 

 of view. The first-named is what is called a parallel- 

 ist ; that is, he believes that mental processes and bodily 

 processes are not causally related, but form two parallel and 

 non-interfering series of events. In the study of animals, 

 both the physical and the psychical series should, he thinks, 

 be investigated. Biology should use two parallel methods, 

 the one ascending, attempting to explain animal behavior by 

 physical and chemical laws; the other descending, giving 

 an account of the mental processes of animals. Ultimately, 

 it may be hoped, accordingito Claparede, that both jnethods 

 will be applied throughout the whole range of animal life. 

 At present the ascending method is most successful with the 

 lowest forms, the descending method with the highest forms. 

 We cannot afford to abandon the psychological study of 

 animals, for our knowledge of the nervous processes under- 

 lying the higher mental activities is very sKght ; physiology 

 here fails us, and psychology must be left in command of 

 the field. The danger besetting the attempt at a purely 

 physical explanation of animal behavior is that the facts 

 shall be unduly simplified to fit the theory. Thus Bethe's 

 effort at explaining the way in which bees find their way 

 back to the hive as a reflex response, or tropism, produced 

 by "an unknown force," is highly questionable; the facts 

 seem to point toward the exercise of some sort of memory 

 by the bees. It is always possible, further, that the tropism 

 is accompanied by consciousness. A physiologist from 

 Saturn might reduce all human activities to tropisms, says 

 Claparede in a striking passage. "The youth who feels 

 himself drawn to medical studies, or he who is attracted 

 to botany, can no more account for his profoundest aspira- 

 tions than the beetle which runs to the odor of a dead 

 animal or the butterfly invited by the flowers ; and if the 



