THE SCOPE OF PHILOSOPHY 



to possess a science of life. Our power of pre- 

 vision in biology is for the most part strictly 

 limited to the kind of effect which will follow a 

 given cause; it is seldom, if ever, that we can 

 foretell the precise amount of effect ; and even 

 with respect to the kind of effect, we cannot 

 always be sure beforehand. Biology is not an 

 exact science, like chemistry, and perhaps never 

 will be. Nevertheless, biology is such an admi- 

 rably organized body of truths-; its classification, 

 both of objects and of relations, has been car- 

 ried to such a considerable extent ; and the sub- 

 ordination, the mutual coherence and congruity 

 of its verified propositions is so striking ; that 

 we should no more think of doubting its claims 

 to be called a science than we should doubt the 

 claims of astronomy. 



Thus we may end our comparison of scien- 

 tific with unscientific knowledge. Along with 

 generic identity between the two, we have noted 

 five points of gradational difference. We have 

 seen that science and common knowledge alike 

 consist in the classification of phenomena in 

 their relations of coexistence and sequence. But 

 we have also seen that science differs from com- 

 mon knowledge in its superior power of quan- 

 titative prevision, in the remoteness, the gener- 

 ality, and the abstractness of the relations which 

 it classifies, and in the far more complete mu- 

 tual subordination and coherence of its groups 



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