OBVERSE A PRIORI PRINCIPLE. 407 



reverse. And if so, every addition to individual life thus 

 implied, necessarily delays or diminishes the casting off of 

 matter to form new individuals. 



Other things equal, too, a greater degree of organization 

 involves a smaller degree of that disorganization shown by 

 the separation of reproductive gemtnas and germs. Detach- 

 ment of a living portion or portions from what was previously 

 a living whole, is a ceasing of co-ordination ; and is therefore 

 essentially at variance with that establishment of greater co- 

 ordination which is achieved by structural development. In 

 the extreme cases where a living mass is continually dividing 

 and subdividing, it is manifest that there cannot arise much 

 physiological division of labour; since progress towards 

 mutual dependence of parts is prevented by the parts 

 becoming independent. Contrariwise, it is equally clear 

 that in proportion as the physiological division of labour is 

 carried far, the separative process must be localized in some 

 comparatively small portion of the organism, where it may 

 go on without affecting the general structure must become 

 relatively subordinate. The advance that is shown by 

 greater heterogeneity, must be a hindrance to multiplication 

 in another way. For organization entails cost. That transfer 

 and transformation of materials implied by differentiation, 

 can be effected only by expenditure of force ; and this sup- 

 poses consumption of digested and absorbed food, which might, 

 otherwise have gone to make new organisms, or the germs of 

 them. Hence, that individual evolution which consists in 

 progressive differentiation, as well as that which consists in 

 progressive integration, necessarily diminishes that species 

 of dissolution, general or local, which propagation of the race 

 exhibits. 



In active organisms we have yet a further opposition 

 between self-maintenance and maintenance of the race. All 

 motion, sensible and insensible, generated by an animal 

 for the preservation of its life, is motion liberated from 

 decomposed nutriment nutriment which, if not thus decom- 



