Preface xi 



ent conditions that have been specially useful in carrying 

 them out. 



Probably no one zoological item has influenced me more 

 than the perception that the evolutionary interpretation of 

 man does not mean that man's derivation from the lower 

 animals made him something that is now not animal. It 

 means that man is just as much an animal to-day as were 

 his prehuman ancestors. The truth is exactly stated by 

 saying that when the transformation took place by which 

 man came into existence that transformation was from a 

 lower to a higher stage of animal life. The actual problem, 

 consequently, of man's nature is not as to what man is in 

 opposition to animals, but as to the kind, or species of ani- 

 mal he is. 



With the distinction here made once fully grasped comes 

 the revelation tliat man is an object of zoological research 

 and treatment no less certainly than is a horse, a fish, a 

 lobster, or an amoeba. But since man's highest, that is his 

 psychical or spiritual attributes are the ones most decisive 

 of his hvnd, it is these attributes which make him particularly 

 interesting, zoologically speaking — just as, for example, it 

 is the attributes of a horse as a horse, and not as an animal 

 generally that elicits our particular interest in the horse. 

 Zoology rightly understood is preeminent among all the 

 sciences as the science of particulars. This important truth 

 seems to have been first appreciated by Aristotle; and the 

 fact that one of the most fundamental differences between 

 him and his teacher, Plato, concerned the doctrine of Par- 

 ticulars as opposed to that of Universals, is probably con- 

 nected closely with Aristotle's great interest in and attention 

 to zoology. I have not seen any reference to this surmise 

 by writers on Aristotle and his philosophy, yet it appears 

 to me highly significant. 



From these perceptions relative to the nature of man and 

 the science of animal life, it follows that when the zoological 



