ON THE OKIGIN OF THE PLANETARY SYSTEM. 141 



Natural Philosophy, and are far in advance of their 

 times with a number of the happiest ideas. His 

 philosophical writings at this period are but few, and 

 partly like his introductory lecture, directly originat- 

 ing in some adventitious circumstance ; at the sam 

 time the matter they contain is comparatively without 

 originality, and they are only important from a des- 

 tructive and partially sarcastic criticism. It cannot be 

 denied that the Kant of early life was a natural 

 philosopher by instinct and by inclination ; and that 

 probably only the power of external circumstances, the 

 want of the means necessary for independent scientific 

 research, and the tone of thought prevalent at the 

 time, kept him to philosophy, in which it was only 

 much later that he produced anything original and 

 important; for the Kritik der reinen Vernunft 

 appeared in his fifty-seventh year. Even in the later 

 periods of his life, between his great philosophical 

 works, he wrote occasional memoirs on natural philo- 

 sophy, and regularly delivered a course of lectures on 

 physical geography. He was restricted in this to the 

 scanty measure of knowledge and of appliances of his 

 time, and of the out-of-the-way place where he lived ; 

 but with a large and intelligent mind he strove after 

 such more general points of view as Alexander von 

 Humboldt afterwards worked out. It is exactly an 

 inversion of the historical connection, when Kant's 



