CHAPTER IV.* 



PROXIMATE CONCEPTION OF LIFE. 



24. To those who accept the general doctrine of Evolu- 

 tion, it need scarcely be pointed out that classifications are 

 subjective conceptions, which have no absolute demarcations 

 in Nature corresponding to them. They are appliances by 

 which we limit and arrange the matters under investigation ; 

 and so facilitate our thinking. Consequently, when we at- 

 tempt to define anything complex, or make a generalization 

 of facts other than the most simple, we can scarcely ever 

 avoid including more than we intended, or leaving out some- 

 thing which should be taken in. Thus it happens that on 

 seeking a definite idea of Life, we have great difficulty in 

 finding one that is neither more nor less than sufficient. Let 

 us look at a few of the most tenable definitions that have 

 been given. While recognizing the respects in which they 

 are defective, we shall see what requirements a more satis- 

 factory one must fulfil. 



Schelling said that Life is the tendency to individuation. 

 This formula, until studied, conveys little meaning. But we 

 need only consider it as illustrated by the facts of develop- 

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



* This chapter and the following two chapters originally appeared in 

 Tart III of the original edition of the Principles of Psychology (1855): form- 

 ing a preliminary which, though indispensable to the argument there devel- 

 oped, was somewhat parenthetical. Having now to deal with the general 

 science of Biology before the more special one of Psychology, it becomes 

 possible to transfer these chapters to their proper place. 

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