James Hilton (novelist) picked "Lost Horizon" as its first title in 1939. For that reason, the novel is frequently called the book that began the "paperback revolution." Hilton is said to have been inspired to write "Lost Horizon", and to invent "Shangri-La" by reading the "National Geographic Magazine" articles of Joseph Rock, an Austrian-American botanist and ethnologist exploring the southwestern Chinese provinces and Tibetan borderlands. Still living in Britain at the time, Hilton was perhaps influenced by the Tibetan travel articles of early travellers in Tibet whose writings were found in the British Library. Christian Zeeman, the Danish father of the mathematician Christopher
Paradise Lost have been well acquainted with his own genius, and to know what it was that Nature had bestowed upon him more bountifully than upon others: the power of displaying the vast, illuminating the splendid, enforcing the awful, darkening the gloomy, and aggravating the dreadful." Milton scholar John Leonard interpreted the "impious war" between Heaven and Hell as civil war: "Paradise Lost" is, among other things, a poem about civil war. Satan raises 'impious war in Heav'n' (i 43) by leading a third of the angels in revolt against God. The term 'impious war' implies that civil war is impious. But