THE LIFE VARIES AS THE CORRESPONDENCE. 89 



the environment. Deatli from disease, arises either when the 

 organism is congenitally defective in its power to balance the 

 ordinary external actions by the ordinary internal actions, or 

 when there has taken place some unusual external action to 

 which there was no answering internal action. Death by 

 accident, implies some neighbouring mechanical changes of 

 which the causes are either unobserved from inattention, or 

 are so intricate that their results cannot be foreseen ; and 

 consequently certain relations in the organism are not adjusted 

 to the relations in the environment. Manifestly, if, to every 

 outer coexistence and sequence by which it was ever in any 

 degree affected, the organism presented an answering process 

 or act ; the simultaneous changes would be indefinitely nu- 

 merous and complex, and the successive ones endless — the 

 correspondence would be the greatest conceivable, and the 

 life the highest conceivable, both in degree and in length. 



§ 36. Before closing the chapter, it will be useful to 

 compare the definition of Life here set forth, with the defini- 

 tion of Evolution set forth in First Principles. Living 

 bodies being bodies which display in the highest degree the 

 structural changes constituting Evolution ; and Life being 

 made up of the functional changes that accompany these 

 structural changes ; we ought to find a certain harmony 

 between the definitions of Evolution and of Life. Such a 

 harmony is not wanting. 



The first distinction we noted between the kind of change 

 shown in Life, and other kinds of change, was its serial 

 character : we saw that vital change is substantially unlike 

 non- vital change, in being made up of successive changes. 

 Now since organic bodies display in so much higher a de- 

 gree than inorganic bodies, those continuous differentiations 

 and integrations which constitute Evolution ; and since the 

 re-distributions of matter thus carried so far in a compara- 

 tively short period, imply concomitant re-distributions of mo- 

 tion ; it is clear that in a given time, organic bodies must 

 5 



