176 DEFINITION OF LIFE BY DE BLAINVILLE. 



definition approaches most nearly that of De Blain- 

 ville, viz. : " Life is the twofold internal movement of 

 composition and recomposition, at once general and 

 -continuous." While it is exempt from Mr. Herbert 

 Spencer's objection that " it equally well describes the 

 -actions going on in a galvanic battery." From want 

 of limitation to changes in one specially constituted 

 -substance, such as the protoplasm, I must object also 

 to the definition of Mr. Spencer himself, viz. : " The 

 definite combination of heterogeneous changes, both 

 simultaneous and successive, in correspondence with 

 -external co-existences and sequences." Here is recog- 

 nized, after John Brown and Fletcher, the fact that 

 certain actions in correspondence with external agencies 

 constitute life ; but in the illustrations which follow, 

 Mr. Spencer does not really distinguish between the 

 -chemical and the vital parts of the functions which 

 are performed by living beings, although, as we shall 

 see, he follows Fletcher in perceiving that they must 

 contain a substance totally different from the chemical 

 compounds known in the laboratory. With Fletcher, 

 ^as with Beale, all structure is dead the true living 

 matter being always structureless and inasmuch as 

 structure is necessary to function, he distinguishes 

 between that and action, defining a function as the 

 action " of an apparatus destined to some specific 

 purpose in the general economy of an organized being." 

 Hence as all living beings perform certain functions 

 l>y means of some non-living structure, however rudi- 

 mentary, all definitions of life by the non- vital prin- 

 ciplists which describe it in varied language as the 

 sum of the functions, define really the life of individual 



