But here’s the thing,” says Paul. “I would bet that if someone did a study and asked, ‘Okay, your kid’s three, rank these aspects of your life in terms of enjoyment,’ and then, five years later, asked, ‘Tell me what your life was like when your kid was three,’ you’d have totally different responses.” WITH THIS SIMPLE OBSERVATION, Paul has stumbled onto one of the biggest paradoxes in the research on human affect: we enshrine things in memory very differently from how we experience them in real time. The psychologist Daniel Kahneman has coined a couple of terms to make the distinction. He talks about the “experiencing self” versus the “remembering self.” The experiencing self is the self who moves through the world and should therefore, at least in theory, be more likely to control our daily life choices. But that’s not how it works out. Rather, it is the remembering self who plays a far more influential role in our lives, particularly when we make decisions or plan for the future, and this fact is made doubly strange when one considers that the remembering self is far more prone to error: our memories are idiosyncratic, selective, and subject to a rangy host of biases. We tend to believe that how an episode ended was how it felt as a whole (so that, alas, the entire experience of a movie, a vacation, or even a twenty-year marriage can be deformed by a bad ending, forever recalled as an awful experience rather than an enjoyable one until it turned sour). We remember milestones and significant changes more vividly than banal things we do more frequently.