On ne prend pas les mouches avec du vinaigre

On ne prend pas les mouches avec du vinaigre is a proverb Hercule Poirot uses as a compact, initially unexplained clue in the investigation of Linnet Doyle’s murder aboard the Karnak. Its recurrence in his final chain of reasoning connects a brief exchange with Race to the need to reconsider how the crime was planned.

Meaning and First Use

The proverb literally evokes the failure of vinegar to catch flies, and in ordinary use conveys that a gentler or more attractive approach succeeds where harshness does not. Poirot does not explain that general meaning when he first uses it. After a smell of pear drops billows into the room and he recorks the bottle, Race asks whether he has learned anything. Poirot answers with the proverb, then says that the murderer has not been obliging. The reply offers no immediate identification of a culprit; it leaves the saying suspended as part of the investigation’s unresolved pattern.

A Clue Among Other Facts

Later, Poirot names the proverb as one element in a group of details he asks Race to consider. The group includes Jacqueline de Bellefort’s statement that someone overheard her conversation with Simon Doyle in the garden at Aswan, Tim Allerton’s account of what he heard and did on the night of the murder, and Louise Bourget’s significant answers. Poirot also points to who drank what: Mrs. Allerton drank water, her son drank whisky and soda, and Poirot drank wine. He adds the existence of two bottles of nail polish and, finally, the pistol wrapped in a cheap handkerchief and a velvet stole before being thrown overboard. By placing the proverb beside these specific statements and objects, Poirot presents it as part of a connected body of clues, though he does not separately spell out its precise meaning.

Reconsidering the Crime

The proverb belongs to the process by which Poirot urges Race to look beyond their first explanation. Their initial theory was that someone had seized an unexpected opportunity to kill Linnet and frame Jacqueline. The pistol’s removal did not fit comfortably with that account: if the murderer wanted to incriminate Jacqueline, taking away the weapon most likely to implicate her seemed contradictory. Poirot says he had treated that contradiction as a stumbling block and imagined elaborate explanations for it.

He eventually recognizes that the starting assumption itself was wrong. The murder was not an impulsive act but a carefully timed plan, worked out in detail, including the drugging of Poirot’s wine so that he would be asleep during the night’s events. The proverb’s place in Poirot’s later inventory links its first, cryptic appearance to this larger reconsideration: it is not a stand-alone solution, but one item in the pattern that makes a fresh reading of the evidence possible.