260 HISTORY OF FORMAL ASTRONOMY. 



original vigor and clearness of thought, from -which true science 

 springs. It is remarkable that the Indians, also, had their heliocentric 

 theorists. Aryabatta 5 (A. D. 1322), and other astronomers of that 

 country, are said to have advocated the doctrine of the earth's revo- 

 lution on its axis ; which opinion, however, was rejected by subse- 

 quent philosophers among the Hindoos. 



Some writers have thought that the heliocentric doctrine was de- 

 rived by Pythagoras and other European philosophers, from some of 

 the oriental nations. This opinion, however, will appear to have little 

 weight, if we consider that the heliocentric hypothesis, in the only 

 shape in which the ancients knew it, was too obvious to require much 

 teaching ; that it did not and could not, so far as we know, receive 

 any additional strength from any thing which the oriental nation" 

 could teach ; and that each astronomer was induced to adopt or reject 

 it, not by any information which a master could give him, but by his 

 love of geometrical simplicity on the one hand, or the prejudices of 

 sense on the other. Eeal science, depending on a clear view of the 

 relation of phenomena to general theoretical ideas, cannot be commu- 

 nicated in the way of secret and exclusive traditions, like the mysteries 

 of certain arts and crafts. If the philosopher do not see that the 

 theory is true, he is little the better for having heard or read the words 

 which assert its truth. 



It is impossible, therefore, for us to assent to those views which 

 would discover in the heliocentric doctrines of the ancients, traces of 

 a more profound astronomy than any which they have transmitted to 

 us. Those doctrines were merely the plausible conjectures of men 

 with sound geometrical notions ; but they were never extended so as 

 to embrace the details of the existing astronomical knowledge ; and 

 perhaps we may say, that the analysis of the phenomena into the 

 arrangements of the Ptolemaic system, was so much more obvious 

 than any other, that it must necessarily come first, in order to form an 

 introduction to the Copernican. 



The true foundation of the heliocentric theory for the ancients was, 

 as we have intimated, its perfect geometrical consistency with the 

 general features of the phenomena, and its simplicity. But it was un- 

 Hkc4y that the human mind would be content to consider the subject 

 under this strict and limited aspect alone. In its eagerness for wide 

 speculative views, it naturally looked out for other and vaguer prin- 

 ciples of connection and relation. Thus, as it had been urged in 



' Lib. U. K. Hist. Ast. p. 11. 



