A moth is a mapmaking creature. When it flies into a candle it’s working from an erroneous map. Maybe the moth’s map says, “Mating opportunities here.”
A human is also a mapmaking creature. Everyone operates from a map, and the map is always getting out of date. Life, the territory described by the map, moves quickly. This means that the map drifts away from the territory, eventually becoming more of a historical artifact than a useful guide.
When there is a wide gap between the map and current world, the person who made the map feels discomfort.
For however long it worked, it was a nice map, and now it doesn’t work any more. In this situation, unlike moths, humans have two choices. One is the path of discovery, in which the map is abandoned or redrawn over and over again.
The other path is one in which the more doubts you have about a map, the more strongly you insist it’s accurate. This is the path that leads the moth into the flame. If you follow this path, you’re living by a fiction, an erroneous map ... essentially what you’re doing is building a prison cell of non-reality to live in, your own little Alcatraz.
It’s the job of the koan to take down your prison walls, to undermine your fictions. Then you might discover that you’re not really suffering from other people or from circumstances. You’re suffering from your maps, your fictions, the prison you yourself have created.
A quote from a book titled, Bring Me the Rhinoceros: And Other Zen Koans That Will Save Your Life, by John Tarrant