The moral of this short story is exemplified with a quote from the author himself: "Everyone is perfidious, a liar, and a phony. Everyone wears a false face."
Certainly, Maître Hauchecorne is deceptive and a liar. When the excessively frugal Hauchecorne sees a piece of string on the ground, the thrifty Norman "thought it worthwhile to pick up anything that could be useful." When he bends down and picks up the string, he notices that his foe, Maître Malandin, observed his action. Feeling somewhat humiliated that his rival saw him bend down for a string, Maître Hauchecorne bends again and pretends to be searching for something he has lost.
It is this "phony" action that proves Hauchecorne's undoing, because soon afterwards there is a public announcement that a black leather pocketbook which contained five hundred francs and some business documents has been lost. Shortly after he has picked up the string, Hauchecorne is called in to the mayor's office, where he is told that he was seen picking up the pocketbook of Maître Houlbrèque of Mannville. The witness is the duplicitous Monsieur Malandin, who has retold the facts in a manner that incriminates Hauchecorne.
Maître Hauchecorne responds, "Hah! He saw me, that old good for nothing! He saw me pick up this bit of string."
Fumbling in his pocket, Hauchecorne finds the piece of string which he has taken. The mayor does not believe him, and says Maître Malandin also observed Hauchecorne continue to search for some coins that must have fallen out of the pocketbook. The mayor sends Hauchecorne away, saying that he will inform the public prosecutor and ask what should be done.
When the story of the lost pocketbook spreads, Maître Hauchecorne repeats his story over and over. People laugh. This causes Hauchecorne to become more annoyed that people do not believe him. He retells his story, but people do not believe him. Malandin laughs when he sees Hauchecorne. Others laugh and tease him. Hauchecorn becomes "heartsick over the injustice of being suspected."
No one believes Hauchecorne. When he is finally acquitted after the pocketbook is found, instead of letting the topic drop, he retells his story, "his whole mind occupied with the yarn." He receives derision, and his "mind begins to weaken." In his deathbed, Hauchecorn coughs out, "Just a bit of string... a little bit of string... see, Mr. Mayor, there it is."