Emperor Wenxuan of Northern Qi winter 549, with rival Liang Dynasty under internal turmoil after the rebellion of Hou Jing (a former Eastern Wei general who had defected to Liang in 547), Gao Yang sent Peng Le to attack the Liang border provinces, taking over the region between the Huai River and Yangtze River with ease. In spring 550, Gao Yang had Emperor Xiaojing convey on him the greater title of Prince of Qi Commandery. Two months later, his title was made the even greater title of Prince of Qi. In summer 550, under advice from the officials Gao Dezheng (高德政), Xu Zhicai (徐之才), and
What Is Mathematics? Expectations" by Charles Dickens. According to Constance Reid, Courant finalized the title after a conversation with Thomas Mann. What Is Mathematics? What Is Mathematics? is a mathematics book written by Richard Courant and Herbert Robbins, published in England by Oxford University Press. It is an introduction to mathematics, intended both for the mathematics student and for the general public. First published in 1941, it discusses number theory, geometry, topology and calculus. A second edition was published in 1996 with an additional chapter on recent progress in mathematics, written by Ian Stewart. The book was based on Courant's course material. Although