OBVERSE 1 PRIORI PRINCIPLE. 427 



rectly made to subserve. While, on the one hand, the in 

 crease of tissue constituting growth is conservative both in 

 essence and in result ; on the other hand, decrease of tissue, 

 either from injury, disease, or old age, is in both essence and 

 result the 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 gemmae 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 be 

 coming 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 com 

 paratively 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 trans 

 fer and transformation of materials implied by differentia 

 tion, can be effected only by expenditure of force; and this 

 supposes 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 propaga 

 tion of the race exhibits. 



In active organisms we have yet a further opposition 



