THE SCOPE OF PHILOSOPHY 



pedes, or of the spiral arrangement of leaves 

 around a stem ; if we seek to generalize the 

 phenomena of heredity, or hybridity, or adapta- 

 tion, or, if we endeavour, with Mr. Darwin, to 

 determine the agency of natural selection in 

 modifying the characteristics of species ; we are 

 still no doubt within the territory of science, 

 but we have arrived at a region in which the 

 inquiries take so wide a sweep, and the results 

 have so immediate a bearing upon other in- 

 quiries outside of biology, that our study may 

 seem to demand some especially descriptive 

 name. Accordingly we find the phrase " tran- 

 scendental biology'* employed by French writ- 

 ers, and elsewhere we meet with the significant 

 title " philosophical biology." Still more sig- 

 nificantly Mr. Spencer, whose treatise on bio- 

 logy is occupied with researches of this high 

 order, speaks of them as constituting a domain 

 of " special philosophy." That is to say, just 

 where this science has reached the widest gen- 

 erality consistent with its being called biology 

 at all, it is characterized as a special kind of phi- 

 losophy. But one more step is needed to reach 

 the level of that philosophy which need not be 

 qualified as special. If, pursuing the same line 

 of advance, we proceed, — as I shall hereafter 

 do, — with the aid of the most general principles 

 of heredity, adaptation, and natural selection, 

 to elucidate some comprehensive theory of life ; 

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