《旧唐书·列传·卷一百零五》
窦群曾谒见王叔文，王叔文命人撤去坐榻才让窦群进来，窦群作揖并说道： 事情总有不可预料的。 
群尝谒王叔文，叔文命撤榻而进。群揖之曰： 夫事有不可知者。 
Dou Qun once visited Wang Shuweng. Wang Shuweng ordered someone to remove the couch and then let Dou Qun in. Dou Qun cupped his hands and bowed while saying: Things are always unpredictable.