《韩非子·喻老》
所以说：白圭巡视长堤时堵塞小洞，老人谨防跑火而涂封缝隙，因此白圭没有水灾，老人没有火灾。
故曰：白圭之行堤也塞其穴，丈人之慎火也涂其隙，是以白圭无水难，丈人无火患。
Therefore, it is said: Bai Gui inspected the dike and blocked the small holes, and the old man sealed the cracks to prevent fire escapes, so Bai Gui did not have a flood, and the old man did not have a fire.