THE DATA OF BIOLOGY. 



Schelling said tliat Life is the tendency to individuation. 

 This formula, until studied, conveys little meaning 1 . But it 



+> O 



needs only to consider it as illustrated by the facts of develop- 

 ment, or by the contrasts between lower and higher forms of 

 life, to recognize its value ; especially in respect of compre- 

 hensiveness. As before shown, however, (First Principles, 

 56), it is objectionable, partly on the ground that it refers, 

 not so much to the functional changes constituting Life, as to 

 the structural changes of those aggregations of matter which 

 manifest Life; and partly on the ground that it includes 

 under the idea Life, much that we usually exclude from it : 

 for instance crystallization. 



The definition of Pticherand, " Life is a collection of 

 phenomena which succeed each other during a limited timo 

 in an organized body," is liable to the fatal criticism, that 

 it equally applies to the decay which goes on after death. 

 For this, too, is " a collection of phenomena which succeed 

 each other during a limited time in an organized body." 



" Life," according to De Blaiiiville, " is the two-fold 

 internal movement of composition and decomposition, at once 

 general and continuous." This conception is in some re- 

 spects too narrow, and in other respects too wide. On the 

 one hand, while it expresses what physiologists distinguish as 

 vegetative life, it excludes those nervous and muscular 

 functions which form the most conspicuous and distinctive 

 classes of vital phenomena. On the other hand, it describes 

 not only the integrating and disintegrating processes going on 

 in a living body, but it equally well describes those going on 

 in a galvanic battery ; which also exhibits a " two-fold in- 

 ternal movement of composition and decomposition, at once 

 general and continuous." 



Elsewhere, I have myself proposed to define Life as " the 

 co-ordination of actions ; "* and I still incline towards this de- 

 finition as one answering to the facts with tolerable precision. 



* See Westminster Review for April, 1852. Art. IV. "A Theory of Popu- 

 fction." 



