掩耳盗铃

During the Spring and Autumn period, Zhi Bo of the Spring and Autumn period, Zhi Bo of the State of Jin destroyed Fan's family. Taking advantage of this occasion, a man went to Fan's house and tried to steal something. As soon as the man entered the gate, he saw that there hung a big bell in the courtyard. The bell was cast in high-quality bronza, and was beautiful in design and shape. The theif was very glad, and decided to carry this beautiful bell back home. But no matter how hard he tried, he could not move the bell, because the bell was both big and heavy. He thought and thought again, and believed there was only one way to solve the problem. He had to break the bell to pieces before he was able to carry them back to his home separately.

The thief found a big iron hammer, with which he struck the bell with all his might. The striking produced an enormous crashing sound,  which might. The striking produced an enormous crashing sound, which made the thief terribly frightened. The thief got flurried, thinking that it was too bad to have produced the crashiing sound which would himself on the bell, trying to muffle the crashing sound with his arms. But how could the crashing sound of the bell be muffled?The crashing sound still kept drifting melodiously to distant places. The more he listened to the sound, the more frightened hw became. He xubconsciously shrank back, and covered his ears hard with his hands. "Hey, the sound becomes fainter, inaudible, "the thief became cheerful at once, " wonderful!The sound of the bell can not be heard when the ears are covered. "He immediately got some odd bits of cloth, made two rolls with them, and had his ears plugged with the two cloth rolls. He thought that in this way nobody could hear the sound of the bell. Feeling relieved, he began striking the bell, one blow after another. The resounding sound of the bell was heard at distant places, and finally people caught the thief by gracing the sound.

This story comes from"Knowing Yourself" in The Annals by Buwei, written just before the Qin Dynasty(221-207 B.C.) was founded. Allegedly, when Li Yuan, Emperor Gao Zu of the Tang Dynasty(618-907),  read this story, he felt it simply ridiculous and said, "This is what is called plugging one's ears while stealing a bell. " 

Later,  people have used the set phrase "plugging one's ears while stealing a bell" to refer to the ignorance and foolishness of the person who deceives himself as well as others.