《论衡·卷二十二·纪妖篇》
高祖带着酒意，于夜间在大泽中小道上行走，让一个人走在前头。走在前头的人回来报告说： 前面有大蛇挡在路上，请往回走吧。 
被酒，夜经泽中，令一人居前，前者还报曰： 前有大蛇当道，愿还。 
Gaozu was walking tipsily on a small path in Dazeshan at night, and he asked a man to walk in front of him. The man in front came back and reported: There is a big snake blocking the road ahead, please turn back.