16 SCIENCE AND PHILOSOPHY OF THE ORGANISM 



with such aims, it seems to me best to arrange the properly 

 scientific material which is to be the basis of my discussions, 

 not along the lines which biology as an independent science 

 would select, 1 but to start from the three different kinds of 

 fundamental phenomena which living bodies offer to in- 

 vestigation, and to attach all systematics exclusively to one 

 of them. For there will not be very much for philosophy 

 to learn from biological systematics at present. 



Life is unknown to us except in association with bodies : 

 we only know living bodies and call them organisms. It 

 is the final object of all biology to tell us what it ultimately 

 means to say that a body is " living," and in what sorts of 

 relation body and life stand one to the other. 



But at present it is enough to understand the terms 

 " body " and " living " in the ordinary and popular sense. 



Eegarding living bodies in this unpretentious manner, 

 and recollecting what the principal characters are of all 

 bodies we know as living ones, we easily find that there 

 are three features which are never wanting wherever life in 

 bodies occurs. All living bodies are specific as to form 

 they " have " a specific form, as we are accustomed to say. 

 All living bodies also exhibit metabolism ; that is to say, 

 they stand in a relation of interchange of materials with 

 the surrounding medium, they take in and give out materials, 

 but their form can remain unchanged duriog these processes. 

 And, in the last place, we can say that all living bodies 

 move ; though this faculty is more commonly known 

 among animals only, even elementary science teaches the 

 student that it also belongs to plants. 



Therefore we may ask for " laws of nature " in biology 



1 See J. Arth. Thomson, The Science of Life, London, 1899. 



