CORRESPONDENCE BETWEEN LIFE AND ITS CIRCUMSTANCES. 77 



the expenditure of certain internal mechanical forces, adapted 

 in amounts and directions to balance or out-balance certain 

 external ones. The recognition of an object is impossible 

 without a harmony between the changes constituting per 

 ception, and particular properties co-existing in the environ 

 ment. Escape from enemies supposes motions within the 

 organism, related in kind and rapidity to motions without it. 

 Destruction of prey requires a particular combination of sub 

 jective actions, fitted in degree and succession to overcome a 

 group of objective ones. And so with those countless auto 

 matic processes exemplified in works on animal instinct. 



In the highest order of vital changes, the same fact is 

 equally manifest. The empirical generalization that guides 

 the farmer in his rotation of crops, serves to bring his actions 

 into concord with certain of the actions going on in plants 

 and soil. The rational deductions of the educated navigator 

 who calculates his position at sea, constitute a series of mental 

 acts by which his proceedings are conformed to surrounding 

 circumstances. Alike in the simplest inferences of the child, 

 and the most complex ones of the man of science, we find a 

 correspondence between simultaneous and successive changes 

 in the organism, and co-existences and sequences in its envi 

 ronment. 



29. This general formula, which thus includes the lowest 

 vegetal processes as well as the highest manifestations of hu 

 man intelligence, will perhaps call forth some criticisms which 

 it is desirable here to meet. 



It may be thought that there are still a few inorganic ac 

 tions included in the definition ; as for example that displayed 

 uy the mis-named storm-glass. The feathery crystallization 

 which, on a certain change of temperature, takes place in the 

 solution contained by this instrument, and which afterwards 

 dissolves to reappear in new forms under new conditions, may 

 be held to present simultaneous and successive changes that 

 are to some extent heterogeneous, that occur with some de- 



