176 SCIENCE IN GRECO-ROMAN ANTIQUITY 



paths. The journey, under these conditions, was not 

 easy, as is shown by the fabliau " of the villein who 

 gained Paradise by pleading " : 



A son chevet par grand hasard 



II ne se trouva pas un diable, pas un ange 



Qui put le reclamer au moment du depart. 



Embarrasse le pauvre here 



Partit sans guide et ne sachant que faire. 



Par bonheur il rencontre et suit I' ange Michel 



Qui menait lors un bienheureux au ciel. 



The scholastic philosophers, particularly Thomas 

 Aquinas, preserved the attitude adopted by the Greek 

 astronomers, whose hypotheses they discussed very 

 freely. " It might be possible," declared Thomas 

 Aquinas, " to explain the apparent movements of the 

 stars by some other method not yet conceived by 

 man." * 



We know how Copernicus during the Renaissance 

 brought into fame the heliocentric system proposed 

 by Aristarchus, while at the same time, like the latter, 

 he kept the conception of a finite universe. Under these 

 conditions his hypothesis could not have a revolutionary 

 character. Being regarded as a mathematical specu- 

 lation, it was studied from this point of view and was 

 found wanting, even by thinkers such as Tycho Brahe. 

 It contradicted the physics of Aristotle without supply- 

 ing the proofs required ; moreover it scarcely simpli- 

 fied the calculations at all, since the movement of the 

 planet Venus, for instance, still required a machinery 

 of five epicycles. 2 



In order to disturb beneficially the minds of men and 

 to find credence, the hypothesis of Copernicus needed 

 to be completed : 



i. By the considerations of Giordano Bruno on the 



1 13 Duhem, Systeme III, p. 354. 



2 24 Sageret, Systeme, p. 194. 



