CORRESPONDENCE BETWEEN LIFE AND ITS CIRCUMSTANCES. 97 



of atomic arrangement. Outside there is another thermal 

 change; inside there is another change of atomic arrange- 

 ment. But subtle as is the dependence of each internal upon 

 each external change, the connexion between them does not, 

 in the abstract, differ from the connexion between the motion 

 of a straw and the motion of the wind that disturbs it. In 

 either case a change produces a change, and there it ends. 

 The alteration wrought by some environing agency on this or 

 any other inanimate object, does not tend to induce in it a 

 secondary alteration which anticipates some secondary altera- 

 tion in the environment. But in every living body there is 

 a tendency towards secondary alterations of this nature ; and 

 it is in their production that the correspondence consists. 

 The difference may be best expressed by symbols. Let A be 

 a change in the environment, and B some resulting change 

 in an inorganic mass. Then A having produced B, the 

 action ceases. Though the change A in the environment is 

 followed by some consequent change a in it; no parallel 

 sequence in the inorganic mass simultaneously generates in it 

 some change & that has reference to the change a. But if 

 we take a living body of the requisite organization, and let 

 the change A impress on it some change C; then, while in 

 the environment A is occasioning a, in the living body C will 

 be occasioning c; of which a and c will show a certain con- 

 cord in time, place, or intensity. And while it is in the 

 continuous production of such concords or correspondences 

 that Life consists, it is ~by the continuous production of them 

 that Life is maintained. , 



The further criticism to be expected concerns certain 

 verbal imperfections in the definition, which it seems impos- 

 sible to avoid. It may fairly be urged that the word corre- 

 spondence will not include, without straining, the various 

 relations to be expressed by it. It may be asked : How can 

 the continuous processes of assimilation and respiration corre- 

 spond with the co-existence of food and oxygen in the environ- 

 ment ? or again : How can the act of secreting some def en- 



