Elegant Musings from the Five Hundred Dan Cave-Heaven original: 五百石洞天揮麈 (Wǔbǎi dàn dòngtiān huīzhǔ). "Five Hundred Dan" (a unit of dry measure for grain) is likely the name of the author's private studio. A Cave-Heaven (Dongtian) is a Taoist term for a sacred grotto or earthly paradise. "Waving the deer-tail whisk" (Huizhu) is a classical idiom for engaging in refined, sophisticated conversation or scholarly writing.