PROXIMATE DEFINITION OF LIFE. 63 



change, there can be no getting from premisses to conclusion. 

 And it is this conspicuous manifestation of change, which 

 forms the substratum of our idea of Life in general. Doubt- 

 less we see innumerable changes to which no notion of vital- 

 ity attaches : inorganic bodies are ever undergoing changes 

 of temperature, changes of colour, changes of aggregation. 

 But it will be admitted that the great majority of the phe- 

 nomena displayed by inorganic bodies, are statical and not 

 dynamical ; that the modifications of inorganic bodies are 

 mostly slow and unobtrusive ; that on the one hand, when 

 we see sudden movements in inorganic bodies, we are apt to 

 assume living agency, and on the other hand, when we see 

 no movements in organic bodies, we are apt to assume death. 

 From all which considerations it is manifest, that be the 

 requisite qualifications what they may, a definition of Life 

 must be a definition of some kind of change or changes. 



On further comparing assimilation and reasoning, with a 

 view of seeing in what respect the change displayed in both 

 differs from non-vital change, we find that it differs in being 

 not simple change, but change made up of successive changes. 

 The transformation of food into tissue, involves mastication, 

 deglutition, chymification, chj^lification, absorption, and those 

 various actions gone through after the lacteal ducts have 

 poured their contents into the blood. Carrying on an argu- 

 ment necessitates a long chain of states of consciousness ; 

 each implying a change of the preceding state. Inorganic 

 changes, however, do not in any considerable degree exhibit 

 this peculiarity. It is true that from meteorologic causes, 

 inanimate objects are daily, sometimes hourly, undergoing 

 modifications of temperature, of bulk, of hygrometric and 

 electric condition. jS'ot only, however, do these modifications 

 lack that conspicuousness and that rapidity of succession 

 which vital ones possess, but vital ones form an additional 

 series. Living as well as not-living bodies are affected 

 by atmospheric influences ; and beyond the changes which 

 these produce, living bodies exhibit other changes, more nu- 



