intellectual stimulation of the whole world west of China, the break-up of old ideas and development of new ones, was enormous.
In Persia this fresh excited Arabic mind came into contact not only with Manichæan, Zoroastrian and Christian doctrine, but with the scientific Greek literature, preserved not only in Greek but in Syrian translations. It found Greek learning in Egypt also. Every-where, and particularly in Spain, it discovered an active Jewish tradition of speculation and discussion. In Central Asia it met Buddhism and the material achievements of Chinese civilization. It learnt the manufacture of paper—which made printed books possible—from the Chinese. And finally it came into touch with Indian mathematics and philosophy.
Very speedily the intolerant self-sufficiency of the early days of faith, which made the Koran seem the only possible book, was dropped.