Freely (Storm on Horseback: The Seljuk Warriors of Turkey, 2008,
etc.) profiles the various caliphates that fostered scholarship
and scientific inquiry during Europe’s Dark Ages. As the eighth
century drew to a close, the author writes, Baghdad became a
beacon illuminating classical antiquity. The Abbasid caliphate,
which had held sway there for several centuries, reached its
peaking during the reign of Harun al-Rashid (786–809), when
Baghdad’s scholars plumbed the known world for long lost books
and documents, including many from the ancient library at
Alexandria. In Baghdad’s library, known as the House of Wisdom,
Greek texts were painstakingly translated into Arabic. But
Islamic scholars did more than just translate, the author notes;
they critiqued Greek thinkers from Archimedes and Aristotle to
Zeno. They questioned ideas on the nature of reality, corrected
astronomical observations and probed medical tracts and
mathematical theorems. In once instance, three wards of a
Baghdad caliph marched a measured d