CLASSIFICATION OF LIVING TYPES 6i 



The partial process of disintegration alone as in 

 isolated radio-active bodies, as distinct from those 

 placed in suitable surroundings, may be regarded as 

 partaking in its last phase of disintegration of 

 vital action. For purpose of classification, therefore, 

 the line to take up is that of metabolic change, and to 

 regard all bodies wherein it is absent ' as absolutely 

 lifeless and all those where it occurs as either 

 actually living or possessing the elements or principle 

 of vitality in its potential form. 



The instability of comparatively stable aggregates 

 whether of molecules, atoms, or electrons, would, 

 therefore, if these aggregates have also the power of 

 coming together as well as of separating, be the 

 fundamental principle in vital actions, and the 

 point from which the development of the subject 

 starts. 



According as aggregates of molecules, the molecules 

 themselves, atoms, and electrons in their various 

 combinations exhibit these qualities or their 

 opposites, may they be regarded as possessing, or as 

 lacking, the energy which leads to vitality ; in that 

 state from which matter may spring into life or fall 

 into absolute inertness. There is extreme difficulty, 

 no doubt often in deciding how far the elements in 

 question are, or are not, to be dealt with in any 

 particular system ; but it is upon this point that 

 subsequent discussion turns. We shall lay down 

 the barrier between living and dead matter, not 

 between the organic and inorganic, but between 

 active and inert matter. This barrier, no doubt, is 



