CHAPTER II. 



LIMITATION OF THE EXPLANATORY DOMAIN OF THE 

 EVOLUTIONARY HYPOTHESIS. 



Preliminary Observation. 



THE opinion is generally held that the natural objects 

 which surround us may, in the first place, be divided 

 into two great and quite different groups the animate 

 and inanimate. The animate, again, are divided into the 

 so-called animals and the plants, and these are treated as 

 separate branches of natural science. The animal king- 

 dom and that of the plants are again divided by systems, 

 agreeing in their main features, into stocks, classes, 

 orders, families, genera, species, and sub-species, etc. 



It is therefore indubitable that, for the acceptance 

 of such a threefold division in the things themselves, 

 some sort of starting-point must exist, otherwise it 

 would have been impossible to establish associated 

 but strictly separated scientific branches, since the 

 definition of those branches is effected according to 

 the difference of their objects. 1 



1 It can well be said that most students of nature, in such division of 

 the natural objects into separated groups, perceive the expression of actual 

 relationship. Otherwise there could not be understood the standpoint of 

 the chemist and physician with regard to * pure ' biological questions, and 

 that of the physiologist and biologist with regard to ' pure ' chemico- 

 physical ones. The physician considers, because he leaves the construction 

 and activity of organisms to the biologist and physiologist, that he is 

 thereby limited in his particular domain, and vice versa the students of the 

 organic branches have their own methods and domain of investigation. 



G 2 



