(973 - c. 1052)
At a young age the prolific polymath al-Biruni, born in what is now Uzbekistan, studied under the astronomer Abu Nasr Mansur. In 1017 he was taken into the service of the sultan Mahmud Ghaznawi, with whom he traveled to India, a journey that aided his studies considerably. He wrote more than a hundred titles, mostly on mathematics and astronomy—one theorized that a landmass likely existed between Europe and Asia. Only twenty-two survive, including Verifying All That the Indians Recount, the Reasonable and the Unreasonable.