There is a story in "Book of Han" about a rich man who was a lover of antiques. Among his large collection was a rare vase made of jade. The vase was of exquisite workmanship and of historical value. He loved it dearly.
One night, he noticed a mouse jumped into the vase and was trying to eat some food which the man had carelessly left there. The sight infuriated the man. In a fit of rage, he threw a stone at the mouse. For sure, the mouse was killed, but the precious vase was also broken.
The loss of the vase pained the man greatly. He deeply regretted his own thoughtlessness had brought such unrecoverable loss. He now realized that anyone who only cares for the present and overlooks consequences is apt to bring disasters upon himself. So he sounded a warning: People should not ruin their precious things to get rid of a mouse, but hesitate to pelt a rat for fear of smashing the dishes beside it.
Now, the idiom "tóu shǔ jì qì" is mainly used to refer to people who are cautious in taking action.
tóu shǔ jì qì
投鼠忌器
?????? 《漢書》中有這么個故事：有個富人很喜歡古董。在他收藏的很多寶貝中，有一件稀有的玉盂，工藝精湛，具有很高的歷史價值，深受這個富人的喜愛。
?????? 一天晚上，一只老鼠跳進了這個玉盂，想去吃里邊的一些剩菜，正巧被這個富人看到了。他非常惱火，盛怒之下，他拿了塊石頭砸向老鼠。當然，老鼠是被砸死了，可是那個珍貴的玉盂也被打破了。
?????? 這件事使富人非常難過，他深深后悔自己的魯莽帶來的不可挽回的損失。他認識到：只考慮眼前，而忽視后果，將給自己帶來災難。因此，他向世人發出警告：要“投鼠忌器”，不要為了除掉一只老鼠而毀掉自己珍貴的寶物。
?????? 現在，成語“投鼠忌器”常用來比喻做事有所顧忌，不敢放手進行。
yǐn láng rù shì
引狼入室
bring the wolf into the house – open the door to a dangerous foe
