360 PHYSICAL SCIENCE IN THE MIDDLE AGES. 



contemplation of the future progress of knowledge, 

 that it is difficult to conceive how such a character 

 could then exist. That he received much of his 

 knowledge from Arabic writers, there can be no 

 doubt ; for they were in his time the repositories of 

 all traditionary knowledge. But that he derived 

 from them his disposition to shake off the authority 

 of Aristotle, to maintain the importance of experi- 

 ment, and to look upon knowledge as in its infancy, 

 I cannot believe, because I have not myself hit upon, 

 nor seen quoted by others, any passages in which 

 Arabian writers express such a disposition. On the 

 other hand, we do find in European writers, in the 

 authors of Greece and Rome, the solid sense, the 

 bold and hopeful spirit, which suggest such tenden- 

 cies. We have already seen that Aristotle asserts, 

 as distinctly as words can express, that all know- 

 ledge must depend on observation, and that science 

 must be collected from facts by induction. We 

 have seen, too, that the Roman writers, and Seneca 

 in particular, speak with an enthusiastic confidence 

 of the progress which science must make in the 

 course of ages. When Roger Bacon holds similar 

 language in the thirteenth century, the resemblance 

 is probably rather a sympathy of character, than a 

 matter of direct derivation ; but I know of nothing 

 which proves even so much as this sympathy with 

 regard to Arabian philosophers. 



A good deal has been said of late of the coin- 

 cidences between his views, and those of his groat 



