刻舟求剑：KUH JOU CHIU JIAN

During the Warring States, there was a man from the country of Chu. He was sailing on a small boat when all of a sudden, a gust of wind rocked the boat and knocked his sword into the water. Everyone on the boat expressed concern for him and encouraged him to immediately retrieve the sword. But the man was not worried and simply took out a knife and made a mark on the side of the boat. He then nonchalantly added, "My sword fell at the exact location of this mark."

He then encouraged the boat to keep sailing toward the dock. Everyone on the boat was a bit confused by the man's actions but they kept sailing. Once they docked, the man from Chu removed his clothes and jumped into the waters. He swam around to the location of the mark he made on the side of the boat to look for his sword. And to nobody's surprise, the sword could not be found. 

Moral of the idiom: One cannot be so obstinate and unwillingly to change. While one method might work for one purpose, it might not work elsewhere. Don't settle for an one purpose fits all solution.

ORIGINAL STORY: 刻舟求剑

战国时，有个楚国人乘坐一条小船过江。一阵风吹来，小船猛一摇晃，楚国人随身带的佩剑掉进江里。同船的人赶紧叫船家停船，让楚国人下去打捞。这个楚国人摇摇头，不慌不忙掏出小刀，在船舷上剑掉下去的地方，刻了一个记号，自言自语地说：我的剑是从这儿掉下去的！

然后他起身招呼船家继续行船。大家感到莫名其妙。不一会儿，船靠岸了，这位楚国人脱去衣服，从船舷上刻记号的地方跳下水去。他在水里捞来捞去，结果当然是毫无所获。

这个成语比喻办事刻板，拘泥固执，不知变通。