112 G. F. Becker — Kant as a Natural Philosopher. 



not seem certain that Kepler's laws are sufficiently rigorous for 

 application to ensuing conditions, but if- they are so, the num- 

 ber of bodies would seemingly reduce to two. By the third 

 law, if T is the time of revolution and a the mean distance, 

 T*/a z is the same constant for all the planets. Hence if the 

 solar system reaches a condition in which T is the same for all 

 the planets, a must also be the same, and all the planets must 

 revolve on the same circle. In view of Lagrange's investiga- 

 tions on the stability of the solar system, it hardly seems pos- 

 sible that all the planets should acquire and permanently 

 pursue the same exactly circular orbit unless they were to 

 coalesce to a single mass. 



In his preface to his Theory of the Heavens, Kant says : " I 

 seek to evolve the present state of the universe from the sim- 

 plest condition of nature by means of mechanical laws alone." 

 After more than one hundred and forty years of rapid progress 

 in science, it cannot be denied that his attempt was astonish- 

 ingly successful. 



Washington, D. 0., December, 1897. 



