Your memory keeps only the peak and the end

A classic Kahneman experiment: hold your hand in 14-degree water for 60 seconds. Then another round, identical, but with 30 extra seconds during which the water warms slightly, to 15 degrees. Objectively the second is worse: the same misery plus half a minute more. And yet most people chose to repeat the second one.

It's the peak-end rule: we don't remember experiences as they were, but by their most intense moment and by how they ended. Duration barely counts. A slightly better ending repaints the whole memory.

In a study with real colonoscopies, patients whose procedure ended with a few gentler minutes remembered it as less painful — and came back for check-ups more often.

Use it wisely: the last day of a holiday weighs more than the fifth. And an argument is always worth ending well.