You live life twice: once as experience, once as memory. The experiencing self answers, “How is it right now?” The remembering self answers, “How was it, on the whole?”
These selves can disagree. The remembering self builds summaries, often dominated by peaks and endings, and it tends to neglect duration. A short intense episode can outweigh a long mild one.
Because memory is what you consult when you make choices, the remembering self often governs decisions. You plan future experiences to create better memories, not necessarily better moments.
The fast system produces the immediate feeling; the slow system narrates and evaluates afterward. Both feel like “you,” but they keep different score.
Once you separate them, you can see why some choices optimize the story of life rather than the lived minutes that compose it.