382 HISTORY OF FORMAL ASTRONOMY. 



But, till the appearance of his work, the helio- 

 centric system had never come before the world 

 except as a hasty and imperfect hypothesis ; which 

 bore a favourable comparison with the phenomena, 

 so long as their general features only were known ; 

 but which had been completely thrown into the 

 shade by the labour and intelligence bestowed upon 

 the Hipparchian or Ptolemaic theories by a long 

 series of great astronomers of all civilized countries. 



But, though the astronomers who, before Co- 

 pernicus, held the heliocentric opinion, cannot, on 

 any good grounds, be considered as much more 

 enlightened than their opponents, it is curious to 

 trace the early and repeated manifestations of this 

 view of the universe. The distinct assertion of the 

 heliocentric theory among the Greeks is an evidence 

 of the clearness of their thoughts, and the vigour of 

 their minds; and it is a proof of the feebleness 

 and servility of intellect in the stationary period, 

 that, till the period of Copernicus, no one was found 

 to try the fortune of this hypothesis, modified 

 according to the improved astronomical knowledge 

 of the time. 



The most ancient of the Greek philosophers to 

 whom the ancients ascribe the heliocentric doc- 

 trine, is Pythagoras ; but Diogenes Laertius makes 

 Philolaus, one of the followers of Pythagoras, the 

 first author of this doctrine. We learn from Ar- 

 chimedes, that it was held by his contempo- 

 rary, Aristarchus. " Aristarchus of Samos," says 



