《淮南子·汜论训》
古时候人住在水乡泽国，于堤岸山崖上打洞栖身，冬天难以忍受霜雪雾露的侵袭，夏天难以忍受暑热和蚊虫的叮咬。于是圣人就为百姓筑土构木建成房舍，这样上有瓦梁，下有屋檐可以用来遮风挡雨、躲避寒暑，百姓从此得以安定。
古者民泽处复穴，冬日则不胜霜雪雾露，夏日则不胜暑热蚊虻；圣人乃作，为之筑土构木以为宫室，上栋下宇以蔽风雨，以避寒暑，而百姓安之。
In ancient times, people lived in a water乡沢 country, living in caves on the embankment cliffs, and it was difficult to endure the invasion of frost, snow, fog and dew in winter, and it was difficult to endure the heat and mosquitoes in summer. So the saints built houses for the people with soil and wood, so that they could shelter from the wind and rain, and avoid the cold and heat. From then on, the people were able to settle down.