270 PHYSICAL SCIENCE IN THE MIDDLE AGES. 



of thought, we are not to be surprized if the relations 

 resulting from the best established theories were 

 apprehended in an imperfect and incongruous man- 

 ner. We have some remarkable examples of this ; 

 and a very notable one is the celebrated question of 

 the existence of Antipodes, or persons inhabiting 

 the opposite side of the globe of the earth, and con- 

 sequently having the soles of their feet directly 

 opposed to ours. The doctrine of the globular form 

 of the earth results, as we have seen, by a geometrical 

 necessity, from a clear conception of the various 

 points of knowledge which we obtain, bearing upon 

 that subject. This doctrine was held distinctly by 

 the Greeks ; it was adopted by all astronomers, 

 Arabian and European, who followed them; and 

 was, in fact, an inevitable part of every system of 

 astronomy which gave a consistent and intelligible 

 representation of phenomena. But those who did 

 not call before their minds any distinct representa- 

 tion at all, and who referred the whole question to 

 other relations than those of space, might still deny 

 this doctrine ; and they did so. The existence of 

 inhabitants on the opposite side of the terraqueous 

 globe, was a fact of which experience alone could 

 teach the truth or falsehood ; but the religious re- 

 lations, which extend alike to all mankind, were 

 supposed to give the Christian philosopher grounds 

 for deciding against the possibility of such a race of 

 men. Lactantius 8 in the fourth century, argues this 



8 Inst. 1. iii. 23. 



