William Godwin

“ Here he acquired a knowledge of the language and learning of the Arabians, particularly of their astronomy, geometry and arithmetic; and he is understood to have been the first that imparted to the north and west of Europe a knowledge of the Arabic numerals, a science, which at first sight might be despised for its simplicity, but which in its consequences is no inconsiderable instrument in subtilising the powers of human intellect. He likewise introduced the use of clocks. He is also represented to have made an extraordinary proficiency in the art of magic ”

“ Europe by degrees adopted the practice of resorting to Spain for the purpose of enlarging their sphere of observation and knowledge. Among others Gerbert is reported to have been the first of the Christian clergy, who strung themselves up to the resolution of mixing with the followers of Mahomet, that they might learn from thence things, the knowledge of which it was impossible for them to obtain at home. ”

“ Cardinal Benno, who was an adherent of the anti-popes, and for that reason is supposed to have calumniated Gerbert and several of his successors, affirms that he was habitually waited on by demons, that by their aid he obtained the papal crown, and that the devil to whom he had sold himself, faithfully promised him that he should live, till he had celebrated high mass at Jerusalem. ”