54 INTRODUCTION TO SCIENCE 



recognize the bird as an historic being with a 

 mind of its own. 



Comte maintained very strongly that mechan- 

 ical principles broke down as inapplicable be- 

 yond the physical order, but that is not quite 

 the point. They are applicable in Biology; they 

 have been of great service as a means of inves- 

 tigation hi Biology; their application has brought 

 the characteristically vital into bolder relief. But 

 the point is that they are not exhaustive of what 

 occurs, and that they do not give us distinc- 

 tively biological descriptions. 



It must be clearly understood that Biology 

 has an aim far wider than that of giving an 

 account of the physical and chemical processes 

 that go on in the living body. It has to tell 

 the story of individual development, the story of 

 racial evolution, and the story of the everyday 

 behaviour of the organism. It has to recognize 

 the past living on in the present, the individ- 

 uality and spontaneity of the creature, and, 

 often at least, a dramatic element in life much, 

 in fact, that requires a kind of description very 

 different from that of Chemistry and Physics. 

 In the same way it might be shown that Psy- 

 chology has a particular aim of its own, which is 

 distinct from that of Biology. 



More generally stated, the important idea 

 which we wish to make clear is that what defines 



