Here is an unsettling fact about your own mind. You do not really remember your experiences. You remember a heavily edited highlight reel, and the editor follows some strange rules.

In the 1990s, Daniel Kahneman and a few colleagues ran experiments that probably deserve to be more famous than they are. In one, people held a hand in painfully cold water for sixty seconds. Later they did it again, except this round lasted ninety seconds, with the water warmed slightly at the end so the last stretch was a touch less awful. That second round contained more total discomfort. More seconds, more cold. And yet when people were asked which version they would rather repeat, most picked the longer one.

The peak, the end, and almost nothing else

The pattern held up again and again. When we judge an experience after it is over, we lean almost entirely on two moments — the most intense point, and how it ended. Kahneman called it the peak-end rule. The long boring middle barely registers. The total duration barely registers. A worse experience with a gentle finish can beat a shorter, milder one that stops on a sour note.

A grimmer version of the same study looked at colonoscopies, back when they were done with little sedation. Patients whose procedure ended on a calmer note remembered the whole ordeal as less unpleasant, even when it had actually lasted longer. Their memory quietly rewrote the arithmetic.

There is a self that lives through your life and a different self that remembers it, and the two do not always agree.

What your remembering self does to you

Once you notice this, it is hard to stop. You will book the vacation that was mostly delayed flights and sunburn because you remember the last evening on the beach. You will write off a job as miserable because of how it ended, even though most of it was fine. You will rate a relationship by its final few months instead of its years.

I am not sure there is a neat lesson in this, except maybe one. The story you tell about your own past is exactly that, a story, stitched together from a handful of bright moments by a narrator with a short attention span. It is worth being a little suspicious of it, especially on the days it decides to be unkind.