between the seventh and thirteenth centuries the East was gaining
political strength and was naturally superior to the West where
political organisation and culture had been shattered by the Germanic
invasions; in the East again there was an organic unity of national
strength and intellectual ideals, as the course of development had not
been interrupted. Though special dogmatic points had been changed, the
general religious theory remained unaltered throughout the nearer
East. Thus the rising power of Islam, which had high faculties of
self-accommodation to environment, was able to enter upon the heritage
of the mixed Graeco-Oriental civilisation existing in the East; in
consequence it gained an immediate advantage over the West, where
Eastern ideas were acclimatised with difficulty.

The preponderance of Muhammedan influence was increased by the fact
that Islam became the point of amalgamation for ancient Eastern
cultures, in particular for those of Greece and Persia: in previous
centuries preparation had been made for this process by the steady
transformation of Hellenism to Orientalism. Persia, however, had been
the main source of Eastern civilisation, at any rate since the
Sassanid period: the debt of Byzantine culture to Persia is well
known. Unfortunately no thorough investigation has been made of these
various and important changes, but it is clear that Persian
civilisation sent its influence far westward, at first directly and
later through the medium of Muhammedanism. The same facts hold good
with regard to the diffusion of intellectual culture from Persia. How
far Persian ideas may have influenced the development of Muhammedan
and even of Christian eschatology, we need not here discuss: but the
influence of the great Graeco-Christian schools of Persia was
enormous: they made the Arabs acquainted with the most important works
in Greek and Persian literature. To this fact was due the wide