ON THK VTTALISTIC VIKW OF NATUKK. 395 



(ieiiuaii tongue, have cliaiacU'i-iscd the new ideas Llieii 

 introduced into science, and have brought them home 

 to the intelligence of the educated classes. These two 

 terms have only heen inadequately rendered^ in any 

 other modei-n languaue : thev are the words " Stoff- n. 

 wechsel " and " Kreislauf des Lebens." The former de- Z'^^r^'^-^. 

 notes the continual change of matter connected with u-bcnti- 

 maintenance of form in all living things ; the latter 

 denotes the continual interchange which exists between 

 tlie separate members and the different provinces of the 

 living creation, the circulation of living matter and living 

 processes. Liebig looked u})()u nature on the large and 

 on the small scale as an economy, as a household, and 

 he applied himself to study the conditions of its exist- 

 ence, of its normal and abnormal states. Through 

 Liebig chemistry entered into close alliance with politi- 

 cal economy, or, as it is termed abroad, national economics. 

 We shall see immediately how the progress of science 

 has, in the further course of the century, tended to 

 emphasise this twofold aspect and define it more clearly: 

 how the individual organism, the bearer of life, lias been 

 traced to smaller and smaller dimensions and units, and 

 how, correspondingly, life as we see it on the larger scale 

 has more and more revealed itself as consisting in co- 

 operation, in the collective action of societies made up 

 of individuals. We have on the one side the doctrine 

 of the " Autonomy of the Cell," so elociuentlv proclaimed is. 



■^ . "Autonoiiiy 



by ProfcssoT- Yin'1u)w : nn the otiier side the doctrine of oftueCeii." 



' We shall see farther on Ikjw 

 the word " Metabolism," with its 

 two suborclinate terms " A lui hol- 



ism"' and *' Catabolism," is eveu 

 more expressive than the German 

 term " Stotf wechsel." 



