THE EVOLUTION IDEA 115 



alive, or rather revived, in Arabia. The natural 

 philosophy of the Arabs, which was largely de- 

 rived from Aristotle, was destined to exert a 

 considerable influence in Europe. Between 813 

 and 833 the Historia Animalium and other works 

 of Aristotle were translated into Arabic and 

 were soon held in the greatest reverence. Avi- 

 cenna marked the highest point which science 

 reached in Arabia, and the culmination of the en- 

 cycloj^sedic and original studies. Thereafter there 

 was a decline in the East, and about the same 

 period there came the inauguration of scientific 

 and philosophical studies in the West. Between 

 961 and 976 the scientific works of Aristotle and 

 of Arabic commentators and writers were rap- 

 idly imported into Spain, and the interest in 

 these subjects became intense. 



Avicenna (dSO-lOST ), Avempace ( -1138), 

 Ahuhaccr ( -1185) 



The three scientific writers from whom we 

 may quote fragments are Avicenna in Arabia 

 and Avempace and Abubacer in Spain. Draper^ 

 quotes from Avicenna on the origin of moun- 

 tains, showing that he was a unif ormitarian : 



Mountains may be due to two causes. Either they 

 are effects of upheavals of the crust of the earth, 



'^Intellectual Development of Europe, 1863, p. 305. 



