ORGANIZATION OF THE SCIENCES 



former. Unfortunately, such precedence is not 

 what the argument requires, though it is all that 

 can be established. If we compare like orders 

 of phenomena, we shall see at once that it was 

 phvsics which preceded astronomy. Dynamical 

 astronomy became a science only with the dis- 

 covery of the law of gravitation ; and this law 

 was not discovered, nor could it have been dis- 

 covered, until after the leading generalizations 

 of terrestrial dynamics had been established. 

 For, as Mr. Spencer observes, " What were the 

 laws made use of by Newton in working out 

 his grand discovery ? The law of falling bodies, 

 disclosed by Galileo ; that of the composition 

 of forces, also disclosed by Galileo ; and that of 

 centrifugal force, found out by Huyghens — 

 all of them generalizations of terrestrial phy- 

 sics. . . . Had M. Comte confined his atten- 

 tion to the things and disregarded the words, he 

 would have seen that before mankind scientifi- 

 cally coordinated any one class of phenomena 

 displayed in the heavens, they had previously 

 coordinated a parallel class of phenomena dis- 

 played upon the surface of the earth." ' 



This criticism is a very incisive one. It de- 

 stroys this part of Comte's classification not 

 only from the historical, but also from the logi- 

 cal point of view. It shows that the study of 



1 Spencer's Essays, ist series, p. 179. [Library Edition 

 vol. ii. p. 22.] 



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