《吕氏春秋·察今》篇中讲过两个故事,一则说:楚国人想要袭击宋国,就派人先在流水之上插了标记,标明何处水深何处水浅。不料河水突然暴涨,楚国人却毫无察觉,他们仍然顺着原来的标记摸黑过河,结果淹死了一千多名将士,军队惊慌吼叫,就像都城里的房屋倒塌了一般。河水像历史一样,一刻不停地流动,潮起潮落,有时候会瞬息巨变。只观昨日,不察今天,永远按照一时的水文标记去对付变化无常的河水,也就只能成为河水的牺牲品。另一则讲:一个楚国坐船渡江的人,他的剑从船上滑落到江水里,那人当即在船帮上刻下记号,并说这里是我掉剑的地方。船仍在行驶,当船停下来时,那人便吩咐别人按他原来刻下 In the article “The Spring and Autumn Annals of Lu”, two stories were told. One said: When the Chu people want to attack the Song State, they are sent first to place marks on the water and indicate where and where they are shallow. Unexpectedly, a sudden surge in the water, the Chu people without any notice, they still follow the original mark over the river, the result drowned more than a thousand officers and soldiers, the army roared panic, just like the capital city collapsed housing in general. Like the history of the river, the moment of non-stop flow, ebb and flow, sometimes rapid changes. Just look at yesterday, do not look at today, always in accordance with temporary hydrological markers to deal with the vagaries of the river, it can only become a victim of the river. The other one said: A man who crossed the river by boat in Chu State, his sword slipped from the boat into the river, and the man immediately engraved a sign on the gang and said that it was the place where I dropped the sword. The ship was still moving, and when the ship came to a halt, the man commanded the others to inscribe him